Synchronous X-ray and Radio Mode Changing in Pulsar B0943+10: Evidence for a Rapid Global Transformation of the Magnetosphere
Joanna Rankin
University of Vermont
Pulsars are remarkable sources, capable of producing EM emission from
low-frequency radio waves up to high-energy gamma-rays and from sites close
to the neutron-star surface out to the edges of the magnetosphere. Some
pulsars also exhibit several stable "modal" states with fascinating
modulation properties and in some cases even different spindown torques.
B0943+10 has two such radio modes, one with a carousel of bright accurately
drifting subpulses and another with weak chaotic pulses. Correlated
mode changes in the radiation at different wavelengths are then key to
understanding the physical connections and mechanisms of the emission
regions. Through simultaneous observations with the GMRT, LOFAR, and
XMM-Newton observatories, we have detected synchronous switching in the
radio and X-ray emission properties of B0943+10. When the pulsar is in
its radio "bright" mode, the X-rays are unpulsed and have a non-thermal
spectrum. Conversely, when the pulsar is in a radio "quiet" mode, the
X-ray luminosity more than doubles and a 100%-pulsed thermal component
is observed along with the non-thermal radiation. This indicates rapid,
global changes in magnetospheric conditions, which challenge all proposed
pulsar emission theories.
Date: | Tuesday, 15 January 2013 |
Time: | 16:00 |
Where: | McGill University |
| Ernest Rutherford Physics Building, R.E. Bell Conference Room (room 103) |
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