Latest Developments on Fast Imaging from the ATA

Transcript

1. Casey Law :: TKP Amsterdam :: June 2011 Millisecond Imaging

   of Radio Transients

2. Paper Submitted! Casey Law :: TKP Amsterdam :: June 2011

   http://is.gd/pocopaper

3. The Time Domain •fast transients typically studied with single-dish telescopes.

   •Survey speed: • S = Ω/δΩ * T/δt Parkes Observatory: The Pulsar Workhorse Casey Law :: TKP Amsterdam :: June 2011

4. The Time Domain •fast transients typically studied with single-dish telescopes.

   •Survey speed: • S = Ω/δΩ * T/δt Parkes Observatory: The Pulsar Workhorse •Interferometers preserve phase across array •Why not correlate faster? Casey Law :: TKP Amsterdam :: June 2011

5. Where are the Baryons in the Local Universe? •About half

   of local baryons are ionized in IGM •Only detection via x-ray absorption spectroscopy •Dispersion probes this in a new way. You are here (Courtesy NCSA) Casey Law :: TKP Amsterdam :: June 2011

6. Casey Law :: TKP Amsterdam :: June 2011

7. The Pocket Correlator •CASPER hardware (Glenn Jones) • Correlator 8

   inputs 104 Mhz bandwidth 64 channels 80 μs integrations •Nominal sensitivity 5 Jy/beam, actual 12 Jy/ beam Roach board assembled in Berkeley Installed at ATA. PoCo at left, Data Acq. at right Casey Law :: TKP Amsterdam :: June 2011

8. •Observed over a week in July 2010 •Targets (at 750

   MHz): B0329+54 Crab M31 •ms transients detected in cross correlations! PoCo spectrogram of Crab pulsar Dedispersed Crab pulse PoCo Observations Casey Law :: TKP Amsterdam :: June 2011

9. Imaging Pulsars Casey Law :: TKP Amsterdam :: June 2011

   Movie of dedispersed images during Crab Giant pulse (at 1/40th speed) youtube.com/caseyjlaw

10. Imaging Pulsars Casey Law :: TKP Amsterdam :: June 2011

    Movie of dedispersed images during Crab Giant pulse (at 1/40th speed) youtube.com/caseyjlaw

11. New Dimension, New Algorithms Casey Law :: TKP Amsterdam ::

    June 2011 Pulse energy distribution of B0329+54 using three techniques

12. 1. PoCo shows that radio interferometers can detect and image

    dispersed, millisecond pulses. 2. Fast imaging expands on single- dish time-domain capabilities. 3. Rate of ms pulses in M31 < 4.3/hr. 4. Next implementation could detect extragalactic pulsars, RRATs, or exoplanets. Conclusions Casey Law :: TKP Amsterdam :: June 2011 http://is.gd/pocopaper