LOFAR + Gaia (+ X-ray) Transients

Peter Jonker

Transcript

1. LOFAR + Gaia (+ X-ray?) transients
   Peter Jonker (SRON, RU, CfA)
   co-coordinator of multiwave/messenger follow-up
   LOFAR TKP meeting Amsterdam Jan. 8-10, 2014
   

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2. Transients with expected radio emission
   Jonker, O’Brien et al. ArXiv 1306.2336
   Absolute peak magnitude MV
   Peak X-ray luminosity (erg s-1)
   1E-2 1 1E2 1E4 1E6
   Time scale (seconds)
   1E50
   1E45
   1E40
   1E35
   SN Ia break out
   Flare stars
   X-ray flashes & sub-luminous
   ϒ-ray bursts
   SN IIbc break out
   Classical novae
   -10
   -15
   -20
   -5
   Classical novae
   SN Ia
   SGR Giant flares
   SGR
   intermediate
   flares
   -25
   ϒ-ray bursts
   1E55
   .Ia explosions
   ϒ-ray bursts
   Tidal disruption
   

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3. Gaia scan
   Gaia focal plane
   ~billion pixels...
   Slide adapted from Berry Holl
   

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4. Gaia timescales
   Slide adapted from Berry Holl
   

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5. Gaia timescales
   Number  of  epochs  in  5  yr:  40-­‐240    
   Mean  #:  72
   

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6. Gaia first light image!
   

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7. Gaia: when transients?
   launch
   20 December 2013
   Jan Feb Mar Apr May Jun Jul Aug
   2014
   Reach
   L2
   Ecliptic
   Poles
   Scan
   Nominal
   Scan
   Verification phase
   alerts released
   Sep Oct
   STH/LW 29.10.2013
   Nov
   2013
   Commissioning
   figure from Simon Hodgkin
   

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8. Gaia scans
   courtesy Simon Hodgkin
   

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9. Gaia
   105 106 107 108 109
   black hole mass (M¯
   )
   10-2
   10-1
   100
   101
   102
   103
   detection rate (yr¡1 )
   Alerts for Gaia-detected galaxies: ¢m <¡0:3, G <20
   TDE
   SN Ia
   nuclear SN Ia
   AGN flares
   simulation Sjoert van Velzen
   

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10. LOFAR tracking Gaia
    One single observation can not allocate the full
    
    bandwidth in sub-bands, ~16 MHz “left” to track
    Gaia
    LOFAR LBA bandwidth 10-80 MHz
    

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11. LOFAR / GAIA simultaneous observations?
    
    1 degree/min slew compares well with
    
    LOFAR FOV
    Gehrels PI Swift: 1 month test
    
    ~10% of Swift time to observe
    
    simultaneous with Gaia
    XMM (TOO or DDT) follow-up of transients
    

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12. XRT000519
    Case study: A new fast X-ray transient
    Jonker, Glennie et al. 2013
    

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13. M86
    SDSS
    

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14. 0 5000 10000 15000 20000 25000
    Time (sec)
    10 3
    10 2
    10 1
    100
    0.1-7 keV rate; counts s 1)
    Precursors to the transient
    ~4000 s
    ~4000 s
    

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15. Transient #2 – 3rd January 2011
    Glennie et al. to be submitted
    

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16. Transient #3 – 30th August 2012
    

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17. Mi′ = −6.7 for a Distance Modulus of 31 for M 86
    Transient: archival optical images
    INT 999s i’-band; 2001-3-22
    i’=24.3
    CFHT 2055s i’-band; 2009-5-14/15
    i’>25.6
    

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18. 0 50 100 150 200
    Time (sec)
    10 1
    100
    101
    0.1-7 keV rate; counts s 1)
    Interpretations: peak luminosity?
    LEdd?
    Fpeak (0.5-10 keV)=2x10-10 erg cm-2 s-1
    dM86=16.2 Mpc
    

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19. What is causing the transient: TDE?
    Rosswog, Ramirez-Ruiz, Hix 2009
    

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20. Conclusion:
    #
    Strange Transient
    potentially an IMBH disrupting a WD
    #
    One needs multi-wavelength
    observations
    to successfully classify such events
    

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