The Latest on Beamformed Data and the Status of LOTAAS

Jason Hessels

Transcript

1. Jason Hessels (ASTRON / UvA)
   The Latest on Beam-Formed Data & the
   Start of LOTAAS
   +LOFAR Pulsar Working Group
   TKP - Amsterdam - December 4th, 2012
   

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2. TKP - Amsterdam - December 4th, 2012
   Coherent Stokes Incoherent Stokes
   Beam-Formed Observation
   I IQUV XXYY I
   Online coherent dedispersion (test only)
   1, 16, 32, 64, 128, 256 channels per subband
   5us - 10ms (or more) time res.
   1-300 TABs
   1-8 SAPs 1-8 SAPs
   (+)
   (+ imaging)
   LOFAR v1.0: Beam-Formed Modes
   All written to HDF5 with metadata
   

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3. TKP - Amsterdam - December 4th, 2012
   Testing the First of the New Syncoptic Boards
   

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4. TKP - Amsterdam - December 4th, 2012
   

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5. TKP - Amsterdam - December 4th, 2012
   LOFAR Tied-Array Beams with the Full Core
   Circa 2010
   State-of-the-art State-of-the-art
   Circa 2011
   State-of-the-art
   Circa 2012
   Evolution of Beam-Formed modes
   

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6. TKP - Amsterdam - December 4th, 2012
   #stations x 1.0
   #stations x 0.85
   sqrt(#stations)
   Sensitivity Scaling of Core Tied-Array Beams
   Modestly Bright Pulsar
   

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7. TKP - Amsterdam - December 4th, 2012
   Superterp Tied-Array Beam Mapping
   Shows that a “tune-up” is needed
   

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8. TKP - Amsterdam - December 4th, 2012
   Sensitivity Scaling of Core Tied-Array Beams
   Very Bright Pulsar
   #stations x 1.0
   sqrt(#stations)
   (#stations)^0.75
   

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9. TKP - Amsterdam - December 4th, 2012
   LBA Single Pulses from B0809+74
   

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10. TKP - Amsterdam - December 4th, 2012
    LBA Single Pulses from B0809+74
    

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11. TKP - Amsterdam - December 4th, 2012
    Also using 8-bit mode to go from 15-95MHz
    LBA B0809+74
    

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12. TKP - Amsterdam - December 4th, 2012
    Coherent
    Incoherent
    In General, Best Data Yet
    

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13. TKP - Amsterdam - December 4th, 2012
    Pilot LOFAR Pulsar Surveys
    • LPPS (incoherent survey): ~1/2 of North. Hem., 7 SAPs,1
    hour pointings.
    • LOTAS (coherent survey): ~1000 sq deg., 19 TABs, 17-
    minute pointing.
    • Processing near completion, still lots of candidates to
    inspect.
    • So far 5 independent discoveries of very recent GBT
    discoveries at 350MHz.
    

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14. TKP - Amsterdam - December 4th, 2012
    Pilot LOFAR Pulsar Surveys
    GBT LOFAR
    24-ms Pulsar!
    

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15. TKP - Amsterdam - December 4th, 2012
    LOFAR Tied-Array All-Sky Survey (LOTAAS)
    • Use 8-bit mode
    • 3 SAPs of 36MHz each
    • 1hr per pointing (1.5hr all-sky by end... new param. space)
    • 0.49ms time resolution, 6kHz frequency channels
    • Find millisecond pulsars out to DM ~ 50 pc cm-3
    • 111 tied-array beams, 3 incoherent beams
    • 12 sq deg. total per ptg. from tied-array beams
    • 60 sq deg. total per ptg. from incoherent beams
    • Sparse coverage of North. Hem. takes 333 pointings
    • Dense coverage of North. Hem. takes 1000 pointings
    First (test) survey observations tonight!!!
    

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16. TKP - Amsterdam - December 4th, 2012
    LOFAR Tied-Array All-Sky Survey (LOTAAS)
    

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17. TKP - Amsterdam - December 4th, 2012
    LOFAR Tied-Array All-Sky Survey (LOTAAS)
    

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18. TKP - Amsterdam - December 4th, 2012
    LOFAR Tied-Array All-Sky Survey (LOTAAS)
    • ~2x more sensitive
    than LOTAS (coh.
    pilot survey)
    • ~2x more sensitive
    than LPPS (incoh.
    pilot survey)
    

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19. TKP - Amsterdam - December 4th, 2012
    LOTAAS
    Sparse
    Sampling
    

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20. TKP - Amsterdam - December 4th, 2012
    LOTAAS
    Sparse
    Sampling
    

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21. TKP - Amsterdam - December 4th, 2012
    Papers
    • LOFAR pulsar reference - A&A published
    • Wideband simultaneous observations - A&A published
    • B0943+10 simultaneous XMM - Science in press
    • B0809+74 drifting - A&A submitted
    • Ionospheric RM calibration - A&A submitted
    • Ultra-low-frequency pulses - early draft
    • Profiles of 100 pulsars - early draft
    • B0823+26 switching on - early draft
    • Pilot pulsar surveys - early draft
    

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22. TKP - Amsterdam - December 4th, 2012
    Papers
    • B0943+10 radio properties
    • B0943+10 geometry
    • Deep search of M31
    • Low-frequency pulsar spectra
    • Survey of pulsar RMs
    • LOTAAS description and first discoveries
    • MSP timing
    • Polarized profiles
    • Scattering properties
    • Crab giant pulses
    

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23. TKP - Amsterdam - December 4th, 2012
    Wish list for Sinterklaas
    • Parallel observations
    • Online RFI excision
    • Real-time searches imbedded in the
    correlator
    

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24. 
    
    Spanje
    

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