Correlation of Chandra photons with the radio giant pulses from the crab pulsar

Abstract

No apparent correlation was found between giant pulses (GPs) and X-ray photons from the Crab pulsar during 5.4hr of simultaneous observations with the Green Bank Telescope at 1.5GHz and Chandra X-Ray Observatory primarily in the energy range of 1.5-4.5keV. During the Crab pulsar periods with GPs, the X-ray flux in radio emission phase windows does not change more than by 10% for main pulse (MP) GPs and 30% for interpulse (IP) GPs. During GPs themselves, the X-ray flux does not change by more than two times for MP GPs and five times for IP GPs. All limits quoted are compatible with 2σ fluctuations of the X-ray flux around the sets of false GPs with random arrival times. The results speak in favor of changes in plasma coherence as the origin of GPs. However, the results do not rule out variations in the rate of particle creation if the particles that emit coherent radio emission are mostly at the lowest Landau level. © 2012. The American Astronomical Society. All rights reserved.