天鹅座X-2的光谱学和多普勒层析成像

Variable polarisation and Doppler tomography of PSR J1023+0038 - Evidence for the magnetic propeller during flaring?

Transitional millisecond pulsars are systems that alternate between an accreting low-mass X-ray binary (LMXB) state, and a non-accreting radio pulsar state. When at the LMXB state, their X-ray and optical light curves show rapid flares and dips, origin of which is not well understood. We present results from our optical and NIR observing campaign of PSR J1023+0038, a transitional millisecond pulsar observed in an accretion state. Our wide band optical photopolarimetry indicates that the system shows intrinsic linear polarisation, the degree of which is anticorrelated with optical emission, i.e…

Chandra X-Ray Spectroscopy of the Focused Wind in the Cygnus X-1 System. II. The Nondip Spectrum in the Low/Hard State - Modulations with Orbital Phase

The accretion onto the black hole in the system HDE 226868/Cygnus X-1 is powered by the strong line driven stellar wind of the O-type donor star. We study the X-ray properties of the stellar wind in the hard state of Cyg X-1 as determined with data from the Chandra High Energy Transmission Gratings. Large density and temperature inhomogeneities are present in the wind, with a fraction of the wind consisting of clumps of matter with higher density and lower temperature embedded in a photoionized gas. Absorption dips observed in the light curve are believed to be caused by these clumps. This wor…

Tomography of X-ray Nova Muscae 1991: Evidence for ongoing mass transfer and stream-disc overflow

We present a spectroscopic analysis of the black hole binary Nova Muscae 1991 in quiescence using data obtained in 2009 with MagE on the Magellan Clay telescope and in 2010 with IMACS on the Magellan Baade telescope at the Las Campanas Observatory. Emission from the disc is observed in H alpha, H beta and Ca II (8662 A). A prominent hotspot is observed in the Doppler maps of all three emission lines. The existence of this spot establishes ongoing mass transfer from the donor star in 2009-2010 and, given its absence in the 1993-1995 observations, demonstrates the presence of a variable hotspot …

揭示微类星体隐藏核心的多信使辐射

Unveiling Multimessenger Emission from Hidden Cores of Microquasars

研究利用AMES模拟微类星体多信使辐射，揭示其高能伽马射线起源及中微子通量抑制，探讨不同区域配置对观测特征的影响。

Revisiting the Dynamical Case for a Massive Black Hole in IC10 X-1

The relative phasing of the X-ray eclipse ephemeris and optical radial velocity (RV) curve for the X-ray binary IC10 X-1 suggests the He[$λ$4686] emission-line originates in a shadowed sector of the stellar wind that avoids ionization by X-rays from the compact object. The line attains maximum blueshift when the wind is directly toward us at mid X-ray eclipse, as is also seen in Cygnus X-3. If the RV curve is unrelated to stellar motion, evidence for a massive black hole evaporates because the mass function of the binary is unknown. The reported X-ray luminosity, spectrum, slow QPO, and broad …

XRISM/Resolve 对 Cyg X-3 的 Fe K 区域的观测

The XRISM/Resolve view of the Fe K region of Cyg X-3

利用XRISM/Resolve对Cyg X-3的高分辨率光谱，分解了吸收与发射成分，发现发射线速度振幅高于吸收线，并揭示了风由平滑大尺度成分和致密湍流结构组成。

System mass constraints for the accreting millisecond pulsar XTE J1814-338 using Bowen fluorescence

We present phase-resolved spectroscopy of the millisecond X-ray pulsar XTE J1814-338 obtained during its 2003 outburst. The spectra are dominated by high-excitation emission lines of HeII $λ$4686, H$β$, and the Bowen blend CIII/NIII 4630-50Å. We exploit the proven Bowen fluorescence technique to establish a complete set of dynamical system parameter constraints using bootstrap Doppler tomography, a first for an accreting millisecond X-ray pulsar binary. The reconstructed Doppler map of the NIII $λ$4640 Bowen transition exhibits a statistically significant (>4$σ$) spot feature at the expected p…

EXO 0748-676中子星质量的动力学约束

Dynamical constraints on the neutron star mass in EXO 0748-676

我们介绍了UY的VLT中分辨率光谱，LMXB X射线爆发EXO 0748-676的光学对应物。通过使用多普勒层析成像，我们检测到狭窄的组成部分内的广泛的He II 4542 A，4686 A和5412 A的发射线。这些谱线的相位、速度和窄度与它们从施主星的受辐照半球产生的一致，正如在一些LMXB中观察到的那样。在这个假设下，我们提供了第一个动力学约束在这个系统中的恒星质量。特别地，我们测量K_2>K_em = 300 +/-10 km/s。利用这个值，我们得到主序星伴星的1 M_sun &lt; M_1 &lt; 2.4 M_sun和0.11 &lt; q < 0.28. We find M_1 >1.5 M_sun。我们的结果与Ozel（2006）提出的大质量中子星的存在是一致的，尽管我们不能放弃~1.4 M_sun的正则值。