We report on Chandra X-ray Observatory (CXO) High-Energy Transmission Grating (HETG) spectra of the dipping Low Mass X-ray Binary (LMXB) 1A 1744-361 during its July 2008 outburst. We find that its persistent emission is well modeled by a blackbody (kT ~ 1.0 keV) plus power-law ($Γ$ ~ 1.7) with an absorption edge at 7.6 keV. In the residuals of the combined spectrum we find a significant absorption line at 6.961+/-0.002 keV, consistent with the Fe XXVI (hydrogen-like Fe) 2 - 1 transition. We place an upper limit on the velocity of a redshifted flow of v < 221 km/s. We find an equivalent width for the line of 27^+2_-3 eV, from which we determine a column density of 7+/-1x10^17 cm^-2 via a curve-of-growth analysis. Using XSTAR simulations, we place a lower limit on the ionization parameter of > 10^3.6 erg cm/s. The properties of this line are consistent with those observed in other dipping LMXBs. Using Rossi X-ray Timing Explorer (RXTE) data accumulated during this latest outburst we present an updated color-color diagram which clearly shows that 1A 1744-361 is an "atoll" source. Finally, using additional dips found in the RXTE and CXO data we provide an updated orbital period estimate of 52+/-5 minutes.
Joint XMM-Newton and NuSTAR Observations of Type I X-ray Bursts from the Dipping Low-Mass X-ray Binary 4U 1323-62
Istanbul University(伊斯坦布尔大学);Sabancı University(萨班吉大学);University of Southampton(南安普顿大学);University of Amsterdam(阿姆斯特丹大学);Georgia Institute of Technology(佐治亚理工学院)
4U 1624-490 as a possible intermediate-mass X-ray binary: constraints from XRISM and NuSTAR spectroscopy
Università degli Studi di Palermo(巴勒莫大学);Osservatorio Astronomico di Cagliari, Istituto nazionale di astrofisica(卡利亚里天文台,意大利国家天体物理研究所);INAF – IASF Palermo(意大利国家天体物理研究所帕勒莫天文空间物理研究所);INAF – Osservatorio Astronomica di Brera(意大利国家天体物理研究所布雷拉天文台)
X-ray and Radio Monitoring of the Neutron Star Low Mass X-ray Binary 1A 1744-361: Quasi Periodic Oscillations, Transient Ejections, and a Disk Atmosphere
通过对中子星低质量X射线双星1A 1744-361为期三个月的X射线与射电监测,首次发现约8 Hz准周期振荡,证实其在爆发峰值呈现Z态特征,并观测到 atoll 态下 island 到 banana 态转变时的瞬态喷流抛射及吸积盘大气吸收线。
A highly ionised outflow in the X-ray binary 4U 1624-49 detected with XRISM
ESO(欧洲南方天文台);SRON Netherlands Institute for Space Research(荷兰空间研究所);Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA)(日本宇宙航空研究开发机构宇宙科学研究所);Faculty of Science and Technology, Tokyo University of Science(东京理科大学理工学部);Department of Physics, Ehime University(爱媛大学理学部物理学科);Villanova University(维拉诺瓦大学);NASA/Goddard Space Flight Center(美国国家航空航天局戈达德太空飞行中心);Center for Research and Exploration in Space Science and Technology, NASA/GSFC (CRESST II)(NASA/GSFC空间科学与技术研究探索中心);Center for Space Science and Technology, University of Maryland, Baltimore County (UMBC)(马里兰大学巴尔的摩县分校空间科学与技术中心);Department of Astronomy, University of Michigan(密歇根大学天文学系)
XRISM finds the Changing-Look AGN NGC 1365 in an extended low state: A dense, highly ionized outflow obscures the central source
Massachusetts Institute of Technology(麻省理工学院);Harvard & Smithsonian(哈佛-史密森尼天体物理中心);Technion(以色列理工学院);University of Maryland(马里兰大学);Eureka Scientific, Inc.(尤里卡科学公司);California Institute of Technology(加州理工学院)
XRISM Resolve Spectroscopy of GX 5-1: Constraints on Iron Spectral Features in a Luminous Neutron-Star Binary
RIKEN Nishina Center for Accelerator-Based Science(理化学研究所仁科加速器科学中心);Department of Physics, Rikkyo University(立教大学物理学系);Department of Physics, Kyoto University(京都大学物理学系);Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA)(日本宇宙航空研究开发机构太空科学研究所)
利用 XRISM Resolve 对 Z 源 GX 5-1 进行高分辨率光谱观测,未发现显著铁谱线,给出等效宽度上限,证实其连续谱主导特性。