Pulsed X-rays from the Vela pulsar

Correlation between X‐Ray Light‐Curve Shape and Radio Arrival Time in the Vela Pulsar

“…Much observational work has been done to understand Vela's emission in individual wavelength regions, e.g., the work of Krishnamohan & Downs (1983, hereafter KD83) in the radio regime, observations by Oegelman et al (1993) in the X-ray regime, and studies by Kanbach et al (1994) in the gamma-ray regime. Observations of Vela's spectrum allow for the possibility of both polar cap (Daugherty & Harding 1996) and outer gap (Cheng et al 2000) models of emission.…”

OSSE Observations of the Vela and Geminga Pulsars

“…The pulsed X-ray spectrum, detected by R OSAT, was initially reported Ogelman et al 1993 to be consistent with thermal emission at or near the neutron star surface rather than emission from an e cascade in the magnetosphere, the presumed emission mechanism at other observed frequencies. A more recent i n terpretation Ogelman 1993 suggests that the total spectrum from the point source co-located with the pulsar can also be modeled by soft and hard components, the latter of which m a y indicate a magnetospheric contribution.…”

“…It has been observed extensively at these energies by SAS II Thompson et al 1977, COS-B Bennett et al 1977Grenier, Hermsen &Clear 1988 andEGRET Kanbach et al 1994. In addition to radio emission, the Vela Pulsar also emits faint optical Wallace et al 1977 and soft X-ray pulsations Ogelman, Finley & Zimmermann 1993. While the radio lightcurve exhibits a single peak, the gamma-ray lightcurve is double-peaked, with the rst peak lagging the radio peak by 0:11 in phase and the two gamma-ray peaks separated in phase by 0:42.…”

X-ray emission characteristics of pulsars and their nebulae

“…They exhibit strong steady emission from a pulsar-powered synchrotron nebula (mostly unresolved) combined with a small pulsed contribution of magnetospheric or thermal origin dominating the emission in the range ~ 0.1 -0.5 keV (Becker & Triimper 1996). X-ray pulses are only detected for the Vela pulsar (Ogelman, Finley & Zimmerman 1993). The other Vela-type pulsars are more distant and suffer from photoelectric absorption which prevents the detection of their soft pulses in the presence of the dominant nebula emission.…”