Soft X-Ray Emission from Isolated Pulsars: An Archival Study
Session 78 -- Pulsars and Neutron Stars
Display presentation, Wednesday, 11, 1995, 9:20am - 6:30pm

## [78.04] Soft X-Ray Emission from Isolated Pulsars: An Archival Study

Nicole Lloyd (Cornell University), Patrick Slane (SAO)

Studying Soft X-ray emission from isolated pulsars is necessary to understand both the structure and dynamics of a neutron star. Surface emission associated with cooling of the hot interior allows one to probe the inner structure of the star, while emission associated with the pulsar spin-down power provides information on the magnetosphere.

Here we report initial results from an ongoing study of pulsar X-ray properties. We have derived upper limits to the surface temperatures of eight pulsars, and compared these temperatures with those predicted by standard cooling models. In addition, we derived X-ray luminosities (or upper limits) for each pulsar, assuming a Crab-like power law spectrum; these luminosities have been compared to those expected if the X-ray emission was entirely a result of the pulsar spin-down. For pulsars detected above the $3 \sigma$ level, we performed spectral investigations to confront thermal cooling vs. spin-down scenarios for the origin of the emission. Some of the more interesting results from our investigation include a surface temperature for PSR 1822-09 which marginally constrains some standard neutron star cooling models, and evidence of spin-down origin for emission from PSR 0950+08 that is inconsistent with what is predicted by outer gap models. Additional work is being done on reported potential PSR/SNR associations for two pulsars, as well as on the correlation between pulsars' X-ray fluxes and their gamma-ray flux upper limits (as reported by EGRET).