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Jets from stellar deaths

Rodrigo Nemmen
September 13, 2018

Jets from stellar deaths

Invited talk given by Rodrigo Nemmen with a broad, short introduction to relativistic jets produced from stellar deaths. Slight emphasis on what we can learn with GMT observations.

• Importance of jets
• How jets are produced
• Gamma-ray bursts
• Black hole binaries
• Unification

GMT Science Conference, Stars: Birth and Death. Honolulu, Hawaii.

Rodrigo Nemmen

September 13, 2018
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Transcript

  1. Rodrigo Nemmen
    Universidade de Sao Paulo
    Jets from
    stellar deaths
    M. Weiss, CfA

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  2. Jets from
    stellar deaths
    M. Weiss, CfA
    How jets form
    GRBs
    X-ray binaries
    Unification
    Rodrigo Nemmen
    Universidade de Sao Paulo

    View full-size slide

  3. Why are relativistic jets important?
    Labs for high-energy astrophysics and particle
    acceleration across mass scale
    Beaming 㱺 very high luminosities 㱺 seen at
    high-z ∴ cosmological messengers
    Sources of EM radiation, cosmic rays, neutrinos
    ∴ multimessenger astronomy
    γ
    ν
    p
    Rodrigo Nemmen

    View full-size slide

  4. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    magnetic
    flux tube
    ergosphere
    Requirements
    v

    spinning
    black hole
    Rodrigo Nemmen

    View full-size slide

  5. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    Rodrigo Nemmen

    View full-size slide

  6. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    Rodrigo Nemmen

    View full-size slide

  7. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    P =
    B2
    8⇡
    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
    Rodrigo Nemmen

    View full-size slide

  8. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements

    View full-size slide

  9. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements

    View full-size slide

  10. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    Jet

    View full-size slide

  11. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    Blandford-Znajek
    mechanism:
    Jet power
    rotation frequency
    magnetic flux
    ∝ (ΦΩ)2 ∼ (
    a
    M
    ΦBH)
    2
    ∼ a2
    ·
    Mc2
    (relevant for GRBs and
    microquasars)
    Jet

    View full-size slide

  12. How jets are formed
    large scale B + accretion
    + rotation
    Semenov+2004, Science
    Requirements
    environment
    radiation
    GR
    Lense-Thirring precession
    Complications for theory
    Blandford-Znajek
    mechanism:
    Jet power
    rotation frequency
    magnetic flux
    ∝ (ΦΩ)2 ∼ (
    a
    M
    ΦBH)
    2
    ∼ a2
    ·
    Mc2
    (relevant for GRBs and
    microquasars)
    Jet

    View full-size slide

  13. Best way of producing relativistic jets
    Compact object accreting highly magnetized gas
    magnetized
    accretion flow
    Such conditions are natural outcomes of stellar deaths

    View full-size slide

  14. ~10-4
    pc?
    3C 31
    4 I.F. Mirabel
    Fig. 1.2 The British journal Nature announced on July 16, 1992 the discovery of a microquasar in
    the Galactic center region [22]. The image shows the synchrotron emission at a radio wavelength
    Black hole
    binaries
    (μquasars) ~1 pc
    1E1740.7-2942
    ~1 Mpc ~100 kpc
    Active galactic
    nuclei
    Tidal
    disruption
    events
    Long GRBs
    Gamma-ray bursts
    Short GRBs
    HH 30
    Young
    stellar
    objects
    1000 AU
    106-1010 M⊙
    few-10 M⊙
    106-107 M⊙
    few M

    few-100 M⊙

    View full-size slide

  15. ~10-4
    pc?
    3C 31
    4 I.F. Mirabel
    Fig. 1.2 The British journal Nature announced on July 16, 1992 the discovery of a microquasar in
    the Galactic center region [22]. The image shows the synchrotron emission at a radio wavelength
    Black hole
    binaries
    (μquasars) ~1 pc
    1E1740.7-2942
    ~1 Mpc ~100 kpc
    Active galactic
    nuclei
    Tidal
    disruption
    events
    Long GRBs
    Gamma-ray bursts
    Short GRBs
    HH 30
    Young
    stellar
    objects
    1000 AU
    kilonovas
    supernovae
    GW
    s

    GWs ?

    View full-size slide

  16. ~10-4
    pc?
    4 I.F. Mirabel
    Fig. 1.2 The British journal Nature announced on July 16, 1992 the discovery of a microquasar in
    the Galactic center region [22]. The image shows the synchrotron emission at a radio wavelength
    Black hole
    binaries
    (μquasars) ~1 pc
    1E1740.7-2942
    Long GRBs
    Gamma-ray bursts
    Short GRBs
    GW
    s

    GWs ?
    GMT opportunities
    Jet emission in low and
    very high states
    G-CLEF, GMTNIRS
    • Redshifts G-CLEF
    • Afterglows G-CLEF
    • Kilonovas G-CLEF,
    GMTNIRS, GMTIFS

    View full-size slide

  17. Jets from dying stars
    Stay tuned for transients
    talks tomorrow
    (sessions 10 & 11)

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  18. Jets from collapsars: Long GRBs
    rotating massive star
    MacFadyen & Woosley 1999;
    Woosley & Heger 2006;
    Woosley & Bloom 2006
    M ≳ 30M⊙
    islands of explosion? (Sukhbold’s talk)

    View full-size slide

  19. Jets from collapsars: Long GRBs
    rotating massive star
    MacFadyen & Woosley 1999;
    Woosley & Heger 2006;
    Woosley & Bloom 2006
    M ≳ 30M⊙
    core-collapses
    islands of explosion? (Sukhbold’s talk)

    View full-size slide

  20. Jets from collapsars: Long GRBs
    rotating massive star
    MacFadyen & Woosley 1999;
    Woosley & Heger 2006;
    Woosley & Bloom 2006
    conditions for jet
    production ✔
    M ≳ 30M⊙
    ˙
    M ˙
    MEdd
    BH accretion rate
    accreting
    Kerr BH
    core-collapses
    islands of explosion? (Sukhbold’s talk)

    View full-size slide

  21. Jets from collapsars: Long GRBs
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    collapsar
    Lorentz factor
    γ ≫ 1
    Eiso
    jet
    ∼ 1050 − 1054 erg
    Relativistic jet w/:

    View full-size slide

  22. Jets from collapsars: Long GRBs
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    collapsar
    jet punctures stellar
    envelope → GRB along jet
    axis (beaming)
    Lorentz factor
    γ ≫ 1
    Eiso
    jet
    ∼ 1050 − 1054 erg
    Relativistic jet w/:

    View full-size slide

  23. Jets from collapsars: Long GRBs
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    collapsar
    jet punctures stellar
    envelope → GRB along jet
    axis (beaming)
    GRB followed by isotropic
    explosion: superluminous
    supernovae (type Ic SNe)
    Lorentz factor
    MacFadyen 2001; Woosley & Bloom 2006
    γ ≫ 1
    Eiso
    jet
    ∼ 1050 − 1054 erg
    Relativistic jet w/:
    central engine operation ~ tfreefall
    jet breakout ~ seconds Bromberg+2015
    ∴ duration > few seconds

    View full-size slide

  24. Long GRBs light curve
    ~0-102 s ≳102 s
    Prompt Afterglow
    GRB Cartoon Picture
    Meszaros & Rees 2014
    γ-rays
    radio
    optical
    X-rays

    View full-size slide

  25. Long GRBs light curve
    ~0-102 s ≳102 s
    Prompt Afterglow
    GRB Cartoon Picture
    Meszaros & Rees 2014
    γ-rays
    radio
    optical
    X-rays
    Flux
    Prompt emission
    γ, X-rays
    Afterglow
    radio, optical, X-rays
    Relativistic jet, nonthermal
    Blast wave decelerating
    into ISM
    jet break:
    opening angle,
    energetics
    based on Van
    Eerten 2018

    View full-size slide

  26. Long GRBs light curve
    ~0-102 s ≳102 s
    Prompt Afterglow
    GRB Cartoon Picture
    Meszaros & Rees 2014
    γ-rays
    radio
    optical
    X-rays
    Flux
    Prompt emission
    γ, X-rays
    Afterglow
    radio, optical, X-rays
    Relativistic jet, nonthermal
    Blast wave decelerating
    into ISM
    jet break:
    opening angle,
    energetics
    based on Van
    Eerten 2018

    View full-size slide

  27. Mergers of binary neutron stars: Short GRBs
    NS
    NS
    NS
    BH
    or
    Paczynski 1986; Eichler et al. 1989; Narayan et al. 1992
    time

    View full-size slide

  28. Mergers of binary neutron stars: Short GRBs
    NS
    NS
    Paczynski 1986; Eichler et al. 1989; Narayan et al. 1992
    time
    GWs
    orbit decays due to
    GW emission

    View full-size slide

  29. Mergers of binary neutron stars: Short GRBs
    NS
    NS
    Paczynski 1986; Eichler et al. 1989; Narayan et al. 1992
    time
    neutron rich, magnetized
    accreting torus
    conditions for jet
    production ✔
    GWs
    orbit decays due to
    GW emission
    duration ~ ms

    View full-size slide

  30. Rezzolla+2011
    cf. also Ruiz+2016
    Numerical relativity simulation of NS merger:
    Short GRB emerges naturally
    Rezzolla, Giacomazzo et al. 2011
    Cactus/Carpet/Whisky codes
    (solves Einstein eqs. + ideal MHD)
    Initial condition:
    •NS binary a few orbits before its
    coalescence
    •2 NSs
    •each NS with M=1.5Msun
    •Bmax=1012 G (each star)

    View full-size slide

  31. Rezzolla+2011
    cf. also Ruiz+2016
    gas density magnetic fields

    View full-size slide

  32. Rezzolla+2011
    cf. also Ruiz+2016
    gas density magnetic fields
    Results in:
    • accreting BH, M = 2.91 Msun
    • short GRB jet, Δt = 30 ms
    • opening angle 30 deg
    • amplifies B to 1015 G
    • Eiso = 1049 erg

    View full-size slide

  33. fallback
    material
    GRB jet
    (beamed)
    Ejecta
    (unbeamed)

    View full-size slide

  34. fallback
    material
    GRB jet
    (beamed)
    Lattimer & Schramm 1974

    produces many Earth-mass
    amounts of precious metals
    (r-process, lanthanides)
    Ejecta
    (unbeamed)
    radio
    optical
    X-rays
    γ-rays
    kilonova:
    IR
    optical
    UV

    View full-size slide

  35. fallback
    material
    GRB jet
    (beamed)
    Lattimer & Schramm 1974

    produces many Earth-mass
    amounts of precious metals
    (r-process, lanthanides)
    Ejecta
    (unbeamed)
    radio
    optical
    X-rays
    γ-rays
    kilonova:
    IR
    optical
    UV
    Short GRB multimessenger
    time series: GWs + light
    Fernandez & Metzger 2016

    nandez-Metzger ARI 4 May 2016 13:30
    Event Signal Phase
    Coalescence
    X-ray/radio
    precursor?
    μ
    Ω
    r-process
    ms magnetar?
    Short GRB
    X-ray extended
    emission/plateau
    Ye
    > 0.25
    Ye
    < 0.25
    Free n?
    Shocked ISM
    GW “chirp” GWs from remnant NS?
    Inspiral Dynamical Accretion Remnant
    BH
    ??
    Blue
    kilonova
    ??
    Neutron
    precursor
    (UV)
    Red
    kilonova
    Radio
    transient
    Seconds Milliseconds 10 ms 100 ms Minutes–hours Hours–days Days–weeks Month–years
    Event Signal
    Coalescence
    X-ray/radio
    precursor?
    μ
    Ω
    r-process
    ms magnetar?
    Short GRB
    X-ray extended
    emission/plateau
    Ye
    > 0.25
    Ye
    < 0.25
    Free n?
    Shocked ISM
    GW “chirp” GWs from remnant NS?
    NS
    BH
    NS
    ??
    Blue
    kilonova
    ??
    Neutron
    precursor
    (UV)
    Red
    kilonova
    Radio
    transient
    Figure 1
    Phases of a neutron star (NS) merger as a function of time, showing the associated observational signatures
    and underlying physical phenomena. Abbreviations: BH, black hole; GRB, γ -ray burst; GW, gravitational
    wave; ISM, interstellar medium; n, neutron; UV, ultraviolet; Ye
    , electron fraction. Coalescence inset
    courtesy of D. Price and S. Rosswog (see also Reference 15).

    View full-size slide

  36. fallback
    material
    GRB jet
    (beamed)
    Lattimer & Schramm 1974

    produces many Earth-mass
    amounts of precious metals
    (r-process, lanthanides)
    Ejecta
    (unbeamed)
    radio
    optical
    X-rays
    γ-rays
    kilonova:
    IR
    optical
    UV
    Short GRB multimessenger
    time series: GWs + light
    Fernandez & Metzger 2016

    nandez-Metzger ARI 4 May 2016 13:30
    Event Signal Phase
    Coalescence
    X-ray/radio
    precursor?
    μ
    Ω
    r-process
    ms magnetar?
    Short GRB
    X-ray extended
    emission/plateau
    Ye
    > 0.25
    Ye
    < 0.25
    Free n?
    Shocked ISM
    GW “chirp” GWs from remnant NS?
    Inspiral Dynamical Accretion Remnant
    BH
    ??
    Blue
    kilonova
    ??
    Neutron
    precursor
    (UV)
    Red
    kilonova
    Radio
    transient
    Seconds Milliseconds 10 ms 100 ms Minutes–hours Hours–days Days–weeks Month–years
    Event Signal
    Coalescence
    X-ray/radio
    precursor?
    μ
    Ω
    r-process
    ms magnetar?
    Short GRB
    X-ray extended
    emission/plateau
    Ye
    > 0.25
    Ye
    < 0.25
    Free n?
    Shocked ISM
    GW “chirp” GWs from remnant NS?
    NS
    BH
    NS
    ??
    Blue
    kilonova
    ??
    Neutron
    precursor
    (UV)
    Red
    kilonova
    Radio
    transient
    Figure 1
    Phases of a neutron star (NS) merger as a function of time, showing the associated observational signatures
    and underlying physical phenomena. Abbreviations: BH, black hole; GRB, γ -ray burst; GW, gravitational
    wave; ISM, interstellar medium; n, neutron; UV, ultraviolet; Ye
    , electron fraction. Coalescence inset
    courtesy of D. Price and S. Rosswog (see also Reference 15).

    View full-size slide

  37. Birth of multimessenger astronomy: GWs
    and EM radiation from GW170817

    View full-size slide

  38. Birth of multimessenger astronomy: GWs
    and EM radiation from GW170817

    View full-size slide

  39. Kilonova opportunities for GMT
    lighter elements
    (lanthanide-poor)
    heavier elements
    (lanthanide-rich)
    (UV)
    (NIR)
    cf. also Cowperthwaite+2017

    View full-size slide

  40. Kilonova opportunities for GMT
    lighter elements
    (lanthanide-poor)
    heavier elements
    (lanthanide-rich)
    (UV)
    (NIR)
    cf. also Cowperthwaite+2017

    View full-size slide

  41. Jets from dead stars:
    black hole binaries
    cf. Sung-Chul Yoon’ talk
    tomorrow

    View full-size slide

  42. the galaxy and
    h sites. In these
    s of lower mass
    he black hole.
    igh number of
    e to study their
    not cover here.
    s undergo tran-
    y
    i-
    ht
    n
    o
    se
    n
    n
    st
    ke
    r-
    s-
    a
    he
    s-
    ns
    te
    n
    c,
    r-
    il
    d
    n-
    n-
    h
    of
    s-
    mation of an outburst in the hardness-intensity
    diagram (HID) is presented in the supplementary
    materials (movie S1).
    The rising phase of the outburst (A → B).
    Sources in quiescence are rarely regularly moni-
    tored, and so usually the first thing we know about
    an outburst is an x-ray source rising rapidly in
    luminosity, as detected by x-ray all-sky monitors.
    implying an origin very close to the black hole, and
    can in turn be used to estimate the spin of the black
    hole. This is because of the innermost stable cir-
    cular orbit (ISCO): Within this radius, matter can
    no longer follow a circular orbit and will cross the
    black hole event horizon on very short time scales
    (milliseconds for a black hole of a few solar masses).
    The size of the ISCO depends on the spin of the
    black hole, ranging from 6 RG
    (10)
    for a nonrotating (Schwarzschild)
    black hole to 1 RG
    for a maximally
    rotating (maximal Kerr) black hole.
    Accurate measurements of the de-
    gree of gravitational redshift affect-
    ing the line can be used to infer how
    close the line is to the black hole, and
    from this the spin of the black hole
    itself, although both observation and
    modeling are complex. During the
    hard state, characteristic time scales of
    variability,calledquasi-periodicoscilla-
    tions(QPOs),are also seen to decrease,
    which may correspond to changing
    viscosity or decreasing characteristic
    radii in an evolving accretion disc.
    In this state, sources are always ob-
    served to also show relatively steady
    radio emission at gigahertz radio fre-
    quencies (11). This radio emission
    (LR
    ) correlates in strength with the
    x-ray emission (LX
    ) in a nonlinear
    way: LX
    º LR
    b, where 0.6 < b < 0.7.
    In recent years, it has become appar-
    ent that a less radio-loud branch also
    existsinthehardstate,whichmayhave
    a steeper correlation (12), and yet
    Disc wind
    Jet
    Stream-impact
    point
    X-ray
    heating
    Accretion
    stream
    Accretion
    disc
    Companion
    star
    Fig. 1. An artist’s impression of a low-mass BHXRB. The major components
    of the binary, accretion flow, and outflows are indicated. The inclination and
    relative masses of the binary components are based on estimates for the
    system GX 339-4, a key source in our understanding of black hole accretion
    and the source of the data presented in Fig. 2. [Image produced with BinSim
    on October 26, 2012
    www.sciencemag.org
    ownloaded from
    Rob Hynes
    Black holes in binary systems
    cf. work by Jack Steiner

    View full-size slide

  43. the galaxy and
    h sites. In these
    s of lower mass
    he black hole.
    igh number of
    e to study their
    not cover here.
    s undergo tran-
    y
    i-
    ht
    n
    o
    se
    n
    n
    st
    ke
    r-
    s-
    a
    he
    s-
    ns
    te
    n
    c,
    r-
    il
    d
    n-
    n-
    h
    of
    s-
    mation of an outburst in the hardness-intensity
    diagram (HID) is presented in the supplementary
    materials (movie S1).
    The rising phase of the outburst (A → B).
    Sources in quiescence are rarely regularly moni-
    tored, and so usually the first thing we know about
    an outburst is an x-ray source rising rapidly in
    luminosity, as detected by x-ray all-sky monitors.
    implying an origin very close to the black hole, and
    can in turn be used to estimate the spin of the black
    hole. This is because of the innermost stable cir-
    cular orbit (ISCO): Within this radius, matter can
    no longer follow a circular orbit and will cross the
    black hole event horizon on very short time scales
    (milliseconds for a black hole of a few solar masses).
    The size of the ISCO depends on the spin of the
    black hole, ranging from 6 RG
    (10)
    for a nonrotating (Schwarzschild)
    black hole to 1 RG
    for a maximally
    rotating (maximal Kerr) black hole.
    Accurate measurements of the de-
    gree of gravitational redshift affect-
    ing the line can be used to infer how
    close the line is to the black hole, and
    from this the spin of the black hole
    itself, although both observation and
    modeling are complex. During the
    hard state, characteristic time scales of
    variability,calledquasi-periodicoscilla-
    tions(QPOs),are also seen to decrease,
    which may correspond to changing
    viscosity or decreasing characteristic
    radii in an evolving accretion disc.
    In this state, sources are always ob-
    served to also show relatively steady
    radio emission at gigahertz radio fre-
    quencies (11). This radio emission
    (LR
    ) correlates in strength with the
    x-ray emission (LX
    ) in a nonlinear
    way: LX
    º LR
    b, where 0.6 < b < 0.7.
    In recent years, it has become appar-
    ent that a less radio-loud branch also
    existsinthehardstate,whichmayhave
    a steeper correlation (12), and yet
    Disc wind
    Jet
    Stream-impact
    point
    X-ray
    heating
    Accretion
    stream
    Accretion
    disc
    Companion
    star
    Fig. 1. An artist’s impression of a low-mass BHXRB. The major components
    of the binary, accretion flow, and outflows are indicated. The inclination and
    relative masses of the binary components are based on estimates for the
    system GX 339-4, a key source in our understanding of black hole accretion
    and the source of the data presented in Fig. 2. [Image produced with BinSim
    on October 26, 2012
    www.sciencemag.org
    ownloaded from
    Rob Hynes
    Annu. Rev. Astro. Astrophys. 2006.44:49-92. Downloaded from www.annualreviews.org
    by NASA Goddard Space Flight Center on 12/01/11. For personal use only.
    Remillard & McClintock 2006
    Black holes in binary systems
    cf. work by Jack Steiner

    View full-size slide

  44. thin disk
    RIAF
    jet
    Thermal
    state
    Hard
    state
    Intermediate
    state
    18 C. Done et al.
    Fig. 9 The left hand panel shows a selection of states taken from the 2005 outburst of GRO J1655-40.
    GRO J1655-40
    Done+2007
    Black holes binaries show different states

    View full-size slide

  45. Hardness-intensity diagram: evolution of a
    black hole outburst
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    hard transition, although also sho
    ing a range of luminosities at which
    can occur (even in the same sourc
    generally occurs at a luminosity o
    few percent of the Eddington lum
    nosity (24 ). In fact, the soft state h
    never been convincingly observ
    in any BHXRB at luminosities b
    low 1% Eddington. By the time t
    source reaches the canonical ha
    state again, with almost exactly t
    same spectral and timing charact
    istics as the initial hard state, the
    has reappeared, and the accreti
    disc wind is gone. Once in the ha
    state, the source decline continu
    typically below the detection lev
    of all-sky or regular x-ray monitorin
    and are observed only occasiona
    until their next outburst. These qu
    phases are not without interest, ho
    ever, for it is during these perio
    that—without the glare of the brig
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    Fender & Belloni 2012 Science
    X-ray luminosity
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    hard transition, although also show-
    ing a range of luminosities at which it
    can occur (even in the same source),
    X-ray spectrum
    SOFT HARD
    B
    C
    Black Holes
    soft X-ray spectrum hard
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    of the state transition. It has been re-
    cently shown that in some cases, the
    ejection is coincident in time with the
    appearance of the strong QPOs (15 ).
    The soft state (D → E). As the
    spectral transition continues, these
    strong QPOs disappear, and the over-
    all level of x-ray variability drops as
    hard transition, althou
    ing a range of luminos
    can occur (even in the
    generally occurs at a
    few percent of the E
    nosity (24 ). In fact, th
    never been convinci
    in any BHXRB at lu
    low 1% Eddington. B
    source reaches the c
    state again, with alm
    same spectral and tim
    istics as the initial ha
    has reappeared, and
    disc wind is gone. O
    state, the source dec
    typically below the d
    of all-sky or regular x-
    and are observed on
    until their next outbur
    phases are not withou
    ever, for it is during
    that—without the gla
    accretion disc—resea
    to accurately measure
    tions of the compan
    optical telescopes an
    mate the mass of the
    self (25 , 26 ).
    These cycles of
    clear changes in the w
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    GRS 1915+105
    Similar to H-R diagram
    State-changes in Δt ~ days

    View full-size slide

  46. Hardness-intensity diagram: evolution of a
    black hole outburst
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    hard transition, although also sho
    ing a range of luminosities at which
    can occur (even in the same sourc
    generally occurs at a luminosity o
    few percent of the Eddington lum
    nosity (24 ). In fact, the soft state h
    never been convincingly observ
    in any BHXRB at luminosities b
    low 1% Eddington. By the time t
    source reaches the canonical ha
    state again, with almost exactly t
    same spectral and timing charact
    istics as the initial hard state, the
    has reappeared, and the accreti
    disc wind is gone. Once in the ha
    state, the source decline continu
    typically below the detection lev
    of all-sky or regular x-ray monitorin
    and are observed only occasiona
    until their next outburst. These qu
    phases are not without interest, ho
    ever, for it is during these perio
    that—without the glare of the brig
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    Fender & Belloni 2012 Science
    X-ray luminosity
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    hard transition, although also show-
    ing a range of luminosities at which it
    can occur (even in the same source),
    X-ray spectrum
    SOFT HARD
    B
    C
    Black Holes
    soft X-ray spectrum hard
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    of the state transition. It has been re-
    cently shown that in some cases, the
    ejection is coincident in time with the
    appearance of the strong QPOs (15 ).
    The soft state (D → E). As the
    spectral transition continues, these
    strong QPOs disappear, and the over-
    all level of x-ray variability drops as
    hard transition, althou
    ing a range of luminos
    can occur (even in the
    generally occurs at a
    few percent of the E
    nosity (24 ). In fact, th
    never been convinci
    in any BHXRB at lu
    low 1% Eddington. B
    source reaches the c
    state again, with alm
    same spectral and tim
    istics as the initial ha
    has reappeared, and
    disc wind is gone. O
    state, the source dec
    typically below the d
    of all-sky or regular x-
    and are observed on
    until their next outbur
    phases are not withou
    ever, for it is during
    that—without the gla
    accretion disc—resea
    to accurately measure
    tions of the compan
    optical telescopes an
    mate the mass of the
    self (25 , 26 ).
    These cycles of
    clear changes in the w
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    GRS 1915+105
    low/hard XRB
    low-luminosity
    AGNs, Sgr A*
    N+06; N+14

    View full-size slide

  47. Hardness-intensity diagram: evolution of a
    black hole outburst
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    hard transition, although also sho
    ing a range of luminosities at which
    can occur (even in the same sourc
    generally occurs at a luminosity o
    few percent of the Eddington lum
    nosity (24 ). In fact, the soft state h
    never been convincingly observ
    in any BHXRB at luminosities b
    low 1% Eddington. By the time t
    source reaches the canonical ha
    state again, with almost exactly t
    same spectral and timing charact
    istics as the initial hard state, the
    has reappeared, and the accreti
    disc wind is gone. Once in the ha
    state, the source decline continu
    typically below the detection lev
    of all-sky or regular x-ray monitorin
    and are observed only occasiona
    until their next outburst. These qu
    phases are not without interest, ho
    ever, for it is during these perio
    that—without the glare of the brig
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    Fender & Belloni 2012 Science
    X-ray luminosity
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    hard transition, although also show-
    ing a range of luminosities at which it
    can occur (even in the same source),
    X-ray spectrum
    SOFT HARD
    B
    C
    Black Holes
    soft X-ray spectrum hard
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    of the state transition. It has been re-
    cently shown that in some cases, the
    ejection is coincident in time with the
    appearance of the strong QPOs (15 ).
    The soft state (D → E). As the
    spectral transition continues, these
    strong QPOs disappear, and the over-
    all level of x-ray variability drops as
    hard transition, althou
    ing a range of luminos
    can occur (even in the
    generally occurs at a
    few percent of the E
    nosity (24 ). In fact, th
    never been convinci
    in any BHXRB at lu
    low 1% Eddington. B
    source reaches the c
    state again, with alm
    same spectral and tim
    istics as the initial ha
    has reappeared, and
    disc wind is gone. O
    state, the source dec
    typically below the d
    of all-sky or regular x-
    and are observed on
    until their next outbur
    phases are not withou
    ever, for it is during
    that—without the gla
    accretion disc—resea
    to accurately measure
    tions of the compan
    optical telescopes an
    mate the mass of the
    self (25 , 26 ).
    These cycles of
    clear changes in the w
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    GRS 1915+105
    low/hard XRB
    low-luminosity
    AGNs, Sgr A*
    N+06; N+14
    Open question:
    Nature of state transitions?
    Jet-disk connection

    View full-size slide

  48. Hardness-intensity diagram: evolution of a
    black hole outburst
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    hard transition, although also sho
    ing a range of luminosities at which
    can occur (even in the same sourc
    generally occurs at a luminosity o
    few percent of the Eddington lum
    nosity (24 ). In fact, the soft state h
    never been convincingly observ
    in any BHXRB at luminosities b
    low 1% Eddington. By the time t
    source reaches the canonical ha
    state again, with almost exactly t
    same spectral and timing charact
    istics as the initial hard state, the
    has reappeared, and the accreti
    disc wind is gone. Once in the ha
    state, the source decline continu
    typically below the detection lev
    of all-sky or regular x-ray monitorin
    and are observed only occasiona
    until their next outburst. These qu
    phases are not without interest, ho
    ever, for it is during these perio
    that—without the glare of the brig
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    Fender & Belloni 2012 Science
    X-ray luminosity
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    hard transition, although also show-
    ing a range of luminosities at which it
    can occur (even in the same source),
    X-ray spectrum
    SOFT HARD
    B
    C
    Black Holes
    soft X-ray spectrum hard
    During this phase, the behavior of
    the jet, revealed by infrared and radio
    observations, also begins to change.
    The infrared emission drops almost
    as soon as the state transition begins
    (14 ), indicating a change in the jet
    properties(density andmagneticfield)
    close to the black hole.
    The radio emission begins to vary
    more dramatically, showing oscilla-
    tions and flare events superposed on
    an overall decline (8 , 15 ). At a cer-
    tain point, there are one or more large
    radio flares, which can be two or more
    orders of magnitude more luminous
    than the previous existing, steadier jet
    in the hard state. In several notable
    cases, high-resolution radio observa-
    tions after such flares have directly
    resolved radio- or even x-ray–emitting
    blobs moving away from the central
    black hole (16 , 17 ), which can be
    kinematically traced back to the time
    of the state transition. It has been re-
    cently shown that in some cases, the
    ejection is coincident in time with the
    appearance of the strong QPOs (15 ).
    The soft state (D → E). As the
    spectral transition continues, these
    strong QPOs disappear, and the over-
    all level of x-ray variability drops as
    hard transition, althou
    ing a range of luminos
    can occur (even in the
    generally occurs at a
    few percent of the E
    nosity (24 ). In fact, th
    never been convinci
    in any BHXRB at lu
    low 1% Eddington. B
    source reaches the c
    state again, with alm
    same spectral and tim
    istics as the initial ha
    has reappeared, and
    disc wind is gone. O
    state, the source dec
    typically below the d
    of all-sky or regular x-
    and are observed on
    until their next outbur
    phases are not withou
    ever, for it is during
    that—without the gla
    accretion disc—resea
    to accurately measure
    tions of the compan
    optical telescopes an
    mate the mass of the
    self (25 , 26 ).
    These cycles of
    clear changes in the w
    X-ray spectrum
    X-ray luminosity
    SOFT HARD
    A
    B
    C
    D
    E
    F
    Black Holes
    GRS 1915+105
    low/hard XRB
    low-luminosity
    AGNs, Sgr A*
    N+06; N+14
    Open question:
    Nature of state transitions?
    Jet-disk connection

    View full-size slide

  49. Jet unification

    View full-size slide

  50. Universal mechanism for energy dissipation and jet
    production?
    Mirabel &
    Rodriguez
    2002
    Mirabel

    View full-size slide

  51. log jet
    power
    (erg/s)
    Black hole jets are scale-free: knowledge-
    transfer from stellar to supermassive ones
    Pre-Swift
    Swift BAT
    Fermi GBM/LAT
    BL Lacs
    FSRQs
    log Lγ-rays (erg/s)
    Nemmen+2012, Science
    cf. also Merloni+2003;
    Falcke+2004; McHardy+2006;
    Ma+2014; Lamb+2017;
    ~10
    MSun
    10 8
    -10 9
    M
    Sun
    Ferm
    i blazars
    G
    R
    Bs

    View full-size slide

  52. Summary: Jets from stellar deaths
    Ingredients to produce relativistic jets:
    (i) spinning black holes
    (ii) extended magnetic fields
    (iii) gas accretion
    All of them in collapsars, NSNS mergers and BH binaries
    long GRBs short GRBs μquasars
    prospects
    Jet SEDs in
    low and very
    high states
    Rodrigo Nemmen
    • Spec. and photometric z
    • Afterglow monitoring
    • Kilonova observations

    View full-size slide

  53. Github
    Twitter
    Web
    E-mail
    Bitbucket
    Facebook
    Group
    figshare
    [email protected]
    rodrigonemmen.com
    @nemmen
    rsnemmen
    facebook.com/rodrigonemmen
    nemmen
    blackholegroup.org
    bit.ly/2fax2cT

    View full-size slide

  54. Directors cut

    View full-size slide

  55. optical emission rises in≲1 day, then fades
    with a rapid color evolution to the red
    e spectra shown in Fig. 2 exhibit similarly
    volution; 11 hours after the trigger the
    m is blue and smooth, but it transitions
    a few days to a redder spectrum with at
    ne clear spectral bump near 9000 Å (12).
    ptical spectra lack the numerous absorp-
    atures typically seen in the spectra of or-
    supernovae (10, 12).
    ly every known class of astrophysical
    nts is inconsistent with at least one of the
    ng properties of SSS17a: the rise time of
    urs, subsequent fading at ≳1 mag dayÀ1,
    r difference in V- and H-band magnitudes
    that transitions from À1:2 to þ3:6 mag
    days, and the nearly featureless optical
    at all epochs (10–12). Among previously
    d events dominated by thermal continuum
    n, the most similar class is rapidly evolving
    ansients (21); however, these events have
    agnitudes that are too luminous, typically
    n star-forming galaxies, do not have the
    ed color evolution, and do not fade as
    as SSS17a (10). Nonthermal relativistic
    s such as GRB afterglows can produce
    fading transients but are not expected to
    e the quasi-blackbody spectra that are
    ed (Fig. 2) (12).
    7a’s observational properties suggest a
    nt progenitor system. Various types of
    uration transients have been theorized
    e from white dwarf or massive-star explo-
    but none of these model predictions re-
    SSS17a. For example, models of surface
    ions on a white dwarf (22) could explain
    10000
    1042
    1041
    1040
    8000
    6000
    4000
    2000
    0
    Temperature (K)
    Residual
    Magnitude (+ offset)
    Luminosity (erg s–1)
    Rest-frame days from merger
    0 5 10 15
    0 5 10 15
    0 5 10 15
    0 5 10 15
    12.5
    15.0
    17.5
    20.0
    22.5
    25.0
    27.5
    30.0
    32.5
    35.0
    1
    0
    –1
    on January 2, 2018
    http://science.sciencemag.org/
    loaded from
    Kilpatrick+2017, Science
    Cowperthwaite+2017
    Drout+2017, Science

    View full-size slide

  56. Alexander (Sasha) Tchekhovskoy SPSAS-HighAstro ’17
    Explaining Jet High-Energy Emission
    Binary Merger GRB
    merger
    ejecta,
    wind
    Core collapse GRB
    stellar
    envelope
    R
    AGN
    interstellar
    medium
    kpc
    Magnetic reconnection is promising (Sironi+2015)
    but how to get it to work generically in a smooth jet?
    Universal mechanism to convert 10-50% of jet energy into heat?
    (Panaitescu and Kumar 03, Nemmen+2013)
    Slide: Tchekhovskoy

    View full-size slide

  57. Ultrarelativistic magnetodynamic GRB jets 553
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    Ultrarelativistic magnetodynamic G
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    Figure 2. Idealized model studied in this paper. Th
    the upper panel show an azimuthal cut through a co
    by a razor-thin disc. The star and the disc are thread
    lines, which are shown as thin solid lines. The mag
    the star and the disc is assumed to be perfectly co
    an ultrahigh magnetization parameter. Arrows show
    poloidal electric current. The thick-dashed line indic
    separates the jet from the disc wind. The disc wind pro
    for the jet and plays the role of the gaseous stellar
    The degree of pressure support is adjusted by varyi
    strength profile in the disc. The lower panel shows t
    of rotation of field lines as a function of the cylindrica
    points.
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. Th
    the upper panel show an azimuthal cut through a co
    by a razor-thin disc. The star and the disc are thread
    lines, which are shown as thin solid lines. The mag
    the star and the disc is assumed to be perfectly co
    an ultrahigh magnetization parameter. Arrows show
    poloidal electric current. The thick-dashed line indic
    separates the jet from the disc wind. The disc wind pro
    for the jet and plays the role of the gaseous stellar
    The degree of pressure support is adjusted by varyi
    strength profile in the disc. The lower panel shows t
    of rotation of field lines as a function of the cylindrica
    points.
    parameter σ (Michel 1969; Goldreich & Julian
    σ → ∞. In this idealized model, the force-fr
    the role of the stellar envelope (plus any gase
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘
    idealized model can be considered as a freel
    Figure 1. Cartoon of the large-scale structure of a GRB source (not to
    scale). The major elements are a central engine which launches a polar
    magnetically dominated ultrarelativistic jet, and a gaseous stellar envelope
    (grey shading) which confines the jet. The central engine may be an accreting
    rapidly rotating BH or a millisecond magnetar. For a failed supernova, there
    could also be a disc wind which may additionally confine the jet.
    within the pre-supernova core (Aloy et al. 2000; Zhang et al. 2003;
    Morsony, Lazzati & Begelman 2007; Wang, Abel & Zhang 2007).
    These simulations show that the jet collimates and accelerates as
    it pushes its way through the confining stellar envelope, thus sug-
    gesting that the envelope plays a crucial role in determining the
    opening angle and Lorentz factor of the flow that emerges from the
    star. If the collapsar system forms an accreting BH, then the ultra-
    relativistic jet may be accompanied by a moderately relativistic disc
    wind that may provide additional collimation for the jet (McKinney
    2005b,2006b). We note that the larger the radius of the progenitor
    star and/or the denser the stellar envelope, the more energy is re-
    quired for the jet to have to penetrate the stellar envelope and reach
    Figure 2. Idealized model studied in this paper. The thick solid lines in
    the upper panel show an azimuthal cut through a compact star surrounded
    by a razor-thin disc. The star and the disc are threaded by magnetic field
    lines, which are shown as thin solid lines. The magnetized plasma above
    the star and the disc is assumed to be perfectly conducting and to have
    an ultrahigh magnetization parameter. Arrows show the direction of the
    poloidal electric current. The thick-dashed line indicates the field line that
    separates the jet from the disc wind. The disc wind provides pressure support
    for the jet and plays the role of the gaseous stellar envelope in Fig. 1.
    The degree of pressure support is adjusted by varying the magnetic field
    strength profile in the disc. The lower panel shows the angular frequency
    of rotation of field lines as a function of the cylindrical radius of their foot-
    points.
    parameter σ (Michel 1969; Goldreich & Julian 1970), we assume
    σ → ∞. In this idealized model, the force-free disc wind plays
    the role of the stellar envelope (plus any gaseous disc wind) that
    collimates the jet in a real GRB (Fig. 1).
    In the context of the collapsar picture, the ‘wind’ region of our
    idealized model can be considered as a freely moving pressure
    Long
    GRB
    Tchekhovskoy+08
    AGN
    Similar ingredients for jet launching and collimation in
    GRBs and AGNs: expect scaling of jet properties?
    accretion
    flow
    (torus)
    collapsar
    ˙
    M . ˙
    MEdd
    ˙
    M ˙
    MEdd
    Semenov+04
    Talks by Ioka,
    Kawanaka, ...
    ˙
    M ˙
    MEdd
    Short
    GRB

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  58. 0 5 10 15 20 25 30 35
    0
    2
    4
    6
    8
    10
    12
    14
    16
    18
    20
    Long
    Short
    Opening angle θ
    j
    (degrees)
    Number
    Figure 18
    Distributions of jet opening angles for short (blue) and long (red ) GRBs on the basis of breaks in their
    afterglow emission. Arrows mark lower or upper limits on the opening angles. The observations are
    summarized in Section 8.4. From Fong et al. (2013) and references therein.
    . Downloaded from www.annualreviews.org
    s on 06/05/14. For personal use only.
    Berger 2014 ARAA

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  59. Van Eerten 2018

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  60. slide: optical opportunities for GMT
    afterglow measurements
    what they can teach us
    Log Optical Flux ->
    Log Time ->
    Most GRB Have Optical Afterglows
    Prompt X/-ray light curves
    bright (wide field instruments),
    highly variable,
    inhomogeneous shapes
    LGRB typically ~ 40-100 s
    OPT AG MEASUREMENTS
    COMMON - Hundreds
    observed, dozens per year.
    (Flares ignored here)
    Physics well understood to
    be interaction of a jet with
    ISM.
    [Early or prompt phase not
    measured for most GRBs]
    Covino et al.: The prompt and the afterglow of GRB 060908 5
    10-6
    10-5
    10-4
    10-3
    10-2
    10-1
    100
    101
    102
    101 102 103 104 105 106 107 108
    Flux (mJy)
    Time from burst (s)
    1 keV
    U (x 100)
    B (x 30)
    V (x 10)
    R (x 3)
    I (x 1)
    Z (x 0.4)
    White (x 0.4)
    J (x 0.06)
    H (x 0.035)
    K (x 0.02)
    Covimo+2010
    5.1. The picture since Swift
    Fig. 3. An overview of the various issues raised by GRB afterglow observations from 2004+, in
    particular those by Swift XRT.
    Since the launch of Swift, a complex picture of X-ray and optical afterglows has
    emerged. To some extent, this picture can be described in terms of a canonical long
    GRB afterglow light curve189–191 (see also Fig. 3, expanded from an illustration
    in Ref. 192), although analysis of the Swift XRT sample shows that ‘canonical’
    should be taken with a grain of salt193, 194 and that the measured temporal slopes
    of the light curves span a wide range. After an initial flaring behaviour presumably
    connected to the prompt emission, the light curve drops steeply until it reaches
    a plateau value. The light curve then maintains this value for longer than was
    Eerten 2018

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  61. Slide: Xue-Feng Wu

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  62. GRB optical jet breaks
    Liang+2008

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  63. compar
    Below
    ity will
    relation
    This pre
    BHCs,
    (Kong
    further
    The i
    is in g
    RX; jet
    %
    RX; jet
    %
    Markof
    electron
    (2005).
    to the e
    YUAN & CUI
    410
    Yuan & Cui 2005
    log ν [Hz]

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