$30 off During Our Annual Pro Sale. View Details »

The Good, the Bad and the Ugly: identifying FRATs triggers with TBB data

transientskp
January 09, 2014

The Good, the Bad and the Ugly: identifying FRATs triggers with TBB data

J. Emilio Enriquez

transientskp

January 09, 2014
Tweet

More Decks by transientskp

Other Decks in Science

Transcript

  1. Identifying ‘real’ FRATs
    J. Emilio Enriquez R.
    Heino Falcke, Sander ter Veen,
    Anya Bilous, Arthur Corstanje, Jörg Rachen, Pim Schellart
    LOFAR TKP Meeting
    2014-01-09 1

    View Slide

  2. FRATs : Fast Radio Transients
    ž  Millisecond radio pulses
    — 
    ○ 
    — 
    — 
    — 
    — 
    — 
    — 
    2014-01-09 2

    View Slide

  3. FRATs : Fast Radio Transients
    ž  Millisecond radio pulses possibly originating from:
    —  Lorimer Bursts (FRBs)
    ○  one time extragalactic burst
    —  Pulsars and RRATS
    —  Flaring stars
    —  Lightning from Saturn
    —  Jupiter aurora radio emission
    —  Exoplanets?
    —  ETI ??
    2014-01-09 3

    View Slide

  4. FRATs : Fast Radio Transients
    Detection and Verification
    ž  Detection
    —  Past and present:
    ○  FRATs Trigger Code (Sander’s Talk) by parallel observations
    during LOTAAS (Cycle 0 & 1) and MSSS (tests before Cycle 0)
    so far.
    ○  During Cycle 1 we are expanding to other regular observations
    (beamform and imaging).
    —  Future?:
    ○  LOFAR related : ARTEMIS, AARTFAAC
    ○  Multiwavelength: SWIFT/BAT, Fermi, …
    2014-01-09 4

    View Slide

  5. ž  Detection
    —  FRATs Trigger during parallel LOFAR observations
    Sander ter Veen
    2014-01-09 5

    View Slide

  6. FRATs : Fast Radio Transients
    Detection and Verification
    ž  Verification: Transient Buffer Boards (TBBs)
    —  Parallel System in LOFAR
    —  Ring buffer of raw data from each antenna
    —  Look back in time (5sec)
    —  Offline processing
    2014-01-09 6

    View Slide

  7. FRATs : Fast Radio Transients
    FRATs TBB Goals
    ž  Pulse characterization of
    bright millisecond pulses
    —  High SNR by coherent
    addition of antennas/
    stations.
    ž  Accurate position
    —  Multi-station Imaging
    2014-01-09 7

    View Slide

  8. Pipelines
    ž  First stage pipeline:
    —  False positive
    detection
    —  Human learning
    ž  Second stage pipeline:
    —  TAB
    —  Imaging => Localization
    LOFAR
    locus013
    NIJMEGEN
    Coma Cluster
    2014-01-09 8

    View Slide

  9. Initial Classification
    ž  Good FRATS
    ž  Bad FRATS
    ž  Ugly FRATS
    2014-01-09 9

    View Slide

  10. Good FRATS
    2014-01-09 10
    easy to identify

    View Slide

  11. Dispersion Measure (DM)
    ž  Dispersive nature of interstellar plasma: radio
    wave interaction with free electrons makes for
    slower group velocities for lower frequencies.
    ž  Time delay is calculated by:
    ž  DM Total column density of free electrons,
    or a distance estimate with ne
    models of the ISM.
    2014-01-09 11

    View Slide

  12. Good FRATS
    Example 1
    2014-01-09 12

    View Slide

  13. PSR B0329+54
    Good FRATS
    Example 1
    2014-01-09 13

    View Slide

  14. Good FRATS - Jupiter
    S-Bursts
    L-Bursts
    Example 3
    2014-01-09 14

    View Slide

  15. Good FRATS - Jupiter S-burst
    Olaf Wucknitz
    Example 3
    2014-01-09 15

    View Slide

  16. Good FRATS - Jupiter S-burst
    Olaf Wucknitz
    Example 3
    2014-01-09 16

    View Slide

  17. The Good FRATS
    ž  Easy to identify
    —  Pulsars
    —  Jupiter bursts
    —  Solar flares
    —  …
    2014-01-09 17

    View Slide

  18. Bad FRATS
    Sander ter Veen
    Example 1
    2014-01-09 18
    no useful data

    View Slide

  19. Bad FRATS
    Sander ter Veen
    Example 2
    2014-01-09 19

    View Slide

  20. Bad FRATS
    Example 2
    2014-01-09 20

    View Slide

  21. Bad FRATS
    Example 2
    2014-01-09 21

    View Slide

  22. Bad FRATS
    Example 2
    2014-01-09 22

    View Slide

  23. Bad FRATS
    Example 2
    2014-01-09 23

    View Slide

  24. Bad FRATS
    Example 2
    2014-01-09 24

    View Slide

  25. The Bad FRATS
    ž  Cannot be identified as astrophysical
    source since no data
    —  Out of time range
    —  Bad Antennas
    2014-01-09 25

    View Slide

  26. Ugly FRATS
    Sander ter Veen
    Example 1
    2014-01-09 26
    challenging to identify

    View Slide

  27. Ugly FRATS
    Example 1
    2014-01-09 27

    View Slide

  28. Ugly FRATS
    Example 1
    2014-01-09 28

    View Slide

  29. Ugly FRATS
    Example 1
    2014-01-09 29

    View Slide

  30. Ugly FRATS Solar Flare!
    Example 1
    2014-01-09 30

    View Slide

  31. Ugly FRATS
    Example 2
    2014-01-09 31

    View Slide

  32. Ugly FRATS
    Example 2
    2014-01-09 32

    View Slide

  33. Ugly FRATS
    Example 2
    2014-01-09 33

    View Slide

  34. Ugly FRATS
    Example 2
    2014-01-09 34

    View Slide

  35. Example 2
    Ugly FRATS
    2014-01-09 35

    View Slide

  36. Example 2
    Ugly FRATS
    2014-01-09 36

    View Slide

  37. The Ugly FRATS
    ž  Hard to identify
    —  Bad antennas
    —  Side lobes
    2014-01-09 37

    View Slide

  38. The Ugly FRATS
    ž  Hard to identify
    —  Bad antennas
    —  Side lobes
    ž  But with use of TBB data we can prettify
    the ugly FRATS.
    2014-01-09 38

    View Slide

  39. Conclusion
    ž  With the use of TBBs to identify false positives.
    —  We can verify good FRATS candidates
    —  We can quickly identify bad candidates
    —  We can flag misbehaving antennas
    ž  We can also:
    —  We can localize triggers with better angular precision
    than the incoherent beam.
    —  Can study the pulses with higher SNR than the
    incoherent stokes since can add raw data coherently.
    —  Determine if the FRBs are astrophysical.
    2014-01-09 39

    View Slide

  40. 2014-01-09 40

    View Slide

  41. 2014-01-09 41

    View Slide