Discovery of an 11-s X-Ray Pulsar in the Galactic-Plane Section of the Scorpius Constellation

Publications of the Astronomical Society of Japan

Asanuma, Tatsuhiko²  Yamauchi, Shigeo¹  Koyama, Katsuji⁵  Sugizaki, Mutsumi³  Matsuzaki, Keiichi⁴  Nagase, Fumiaki³  Torii, Ken'ichi²  Kinugasa, Kenzo² 

[1] Faculty of Humanities and Social Sciences, Iwate University, 3-18-34 Ueda, Morioka, Iwate 020;Department of Earth and Space Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560;The Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229 E-mail(MS):;Department of Physics, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113;Department of Physics, Faculty of Science, Kyoto University, Sakyo-ku, Kyoto 606-01

关键词: Pulsars;    "Stars: individual (1RXS J1708490–400910)";    "Stars: neutron";    "X-ray: sources";   

DOI  :  10.1093/pasj/49.5.L25

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

Duringagalactic-planesurveywithASCAin1996September,wedetectedarelativelybright,softsourceatR.A.=17h8m46s.6,DEC.=−40°9′27″(J2000),anddiscoveredan11-sX-raypulsationfromthesource.ThissourcehasbeenidentifiedwiththeROSATsource1RXSJ170849.0−400910.Fromatiminganalysisofthesource,weobtainedabarycentricpulseperiodofP=10.99759±0.00005swithabroadsinusoidalshapeofapulsefractionof∼30%.Theenergyspectruminthe0.8–10keVregionisverysoft,andcanbefittedbyapower-lawmodelwithaphotonindexof3.5andanabsorptioncolumndensityof1.8×1022cm−2.Theobservedpulse-phase-averagedfluxintherange0.8–10keVis4.3×10−11ergcm−2s−1,whichcorrespondsto1.7×10−10ergcm−2s−1aftercorrectingforsoftX-rayabsorption.Duringanobservationintervalofabout14hr,neitherasignificantchangeinthepulsationperiod,norasignificantvariationinthephase-averagedfluxwasdetected.FromtheseX-rayproperties,wesuggestthatthisnewlydiscoveredX-raypulsarmightbeamemberofasmallsubgroupof“anomalous”X-raypulsarswithaperiodcloseto6–9s.

【 授权许可】

Unknown