Variations in the X-ray eclipse transitions of Cen X-3

来源 :天文和天体物理学研究 | 被引量 : 0次 | 上传用户:yy6590
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
We report here an investigation of the X-ray eclipse transitions of the high mass X-ray binary pulsar Cen X-3 in different intensity states.The long term light curve of Cen X-3 obtained with RXTE-ASM spanning more than 5000d shows strong aperiodic flux variations with low and high states.We have investigated the eclipse transitions of Cen X-3 in different intensity states with data obtained from pointed observations with the more sensitive instruments onboard ASCA,BeppoSAX,XMM-Newton,Chandra and RXTE.We found a very clear trend of sharp eclipse transitions in the high state and longer transitions in the low state.This is a confirmation of this feature first observed with the RXTE-ASM but now observed with much better clarity.From the light curves obtained from several missions,it is seen that the eclipse egress in the low state starts earlier by an orbital phase of 0.02 compared to the eclipse egress in the high state indicating that the observed X-rays originate from a much larger region.We have also performed spectral analysis of the post-eclipse part of each observation.From BeppoSAX observations,the out-of-eclipse X-ray flux is found to differ by a factor of~26 during the high and low intensity states while the eclipse count rates differ by a factor of only~ 4.7.This indicates that in the low state,there is an additional scattering medium which scatters some of the source photons towards the observer even when the neutron star is completely eclipsed.We could also resolve the three iron line components using XMM-Newton observation in the low state.By comparing the iron line equivalent width during the high and low states,it is seen that the width of the iron line is relatively large during the low state which supports the fact that significant reprocessing and scattering of X-rays takes place in the low state.
其他文献
脉冲星自转非常稳定,可用作时间标准.然而由单脉冲星定义的脉冲星时受多种噪声源的影响,其频率稳定度还不够好,因此可采取对多颗脉冲星定义的脉冲星时进行综合的方法来削弱各
A continuous air and precipitation sampling for carbonaceous particles was conducted in a field observatory beside Nam Co,Central Tibetan Plateau during July of
Aerosol leads to 30% reduction in solar radiation reaching the earth's surface,and a similar reduction in crops yield for both wheat and rice.To determine the e
桥梁防水工程是要保护钢筋混凝土桥面不受水侵蚀.在桥面上形成牢固的防水屏障。保持在干燥状态下承载和防止钢筋锈蚀。桥梁防水作为桥梁耐久性的一个主要环节,因此越来越受到
We use the redshifi Hubble parameter H(z)data derived from relative galaxy ages,distant type Ⅰa supernovae(SNe Ⅰa),the Baryonic Acoustic Oscillation (BAO)peak
To evaluate the long-term effects of reforestation types on soil erosion on degraded land,vegetation and soil properties under conventional sloping farmland(CSF
Two humic acids (HAs) were isolated from contaminated river sediments present under comparative conditions in the Pearl River Basin, China. YFHA (the HA extract
AIM: To determine the effect of three digestive tract reconstruction procedures on pouch function, after radical surgery undertaken because of gastric cancer, a
新形势下道路施工企业纳税筹划,可以从恰当的选择纳税行业、地区、时间与投融资方式等方面着手,并注意筹划的合法、安全、统筹方面的问题。 Tax planning of road construct
首次跻身国际A级车展的成都车展上,无论是从豪华车品牌的参展规模,还是从对未来市场的布局,都可以看出豪华车是越来越重视西部市场了。 For the first time among the inter