R Turolla,CP Dullemond
R Turolla
In this Letter we investigate the properties of advection-dominated accretion flows (ADAFs) fed by the evaporation of a Shakura-Sunyaev accretion disk (SSD). In our picture, the ADAF fills the central cavity evacuated by the SSD and extends...
Phase Lag and Coherence Function of X-Ray Emission from Black Hole Candidate XTE J1550-564 [0.03%]
暂定候选体XTE J1550-564的X射线辐射的相位延迟和相干函数
W Cui,SN Zhang,W Chen
W Cui
We report the results from measuring the phase lag and coherence function of X-ray emission from black hole candidate XTE J1550-564. These temporal X-ray properties have been recognized to be increasingly important in providing important di...
Correlation among Quasi-Periodic Oscillation Frequencies and Quiescent-State Duration in Black Hole Candidate GRS 1915+105 [0.03%]
黑洞候选体GRS 1915+105的准周期振荡频率与宁静态持续时间的相关性研究
SK Chakrabarti,SG Manickam
SK Chakrabarti
We discover a definite correlation between the frequency of the quasi-periodic oscillations (QPOs) in quiescent states and the duration of the quiescent state of the transient X-ray source GRS 1915+105. We find that while the QPO frequency ...
Rotations and Abundances of Blue Horizontal-Branch Stars in Globular Cluster M15 [0.03%]
球状星团M15内蓝色水平分支 stars的旋转和丰度分布研究
BB Behr,JG Cohen,JK McCarthy
BB Behr
High-resolution optical spectra of 18 blue horizontal-branch stars in the globular cluster M15 indicate that their stellar rotation rates and photospheric compositions vary strongly as a function of effective temperature. Among the cooler s...
Probing the Site for r-Process Nucleosynthesis with Abundances of Barium and Magnesium in Extremely Metal-poor Stars [0.03%]
利用极贫金属星钡镁丰度探测r过程核合成遗址
T Tsujimoto,T Shigeyama,Y Yoshii
T Tsujimoto
We suggest that if the astrophysical site for r-process nucleosynthesis in the early Galaxy is confined to a narrow mass range of Type II supernova (SN II) progenitors, with a lower mass limit of Mms=20 M middle dot in circle, a unique feat...
P Barmby,JP Huchra
P Barmby
We have measured an extensive set of UBVRIJHK colors for M31 globular clusters. We compare the predicted simple stellar population colors of three population synthesis models to the intrinsic colors of Galactic and M31 globular clusters. Th...
The Optical Gravitational Lensing Experiment: Red Clump Stars as a Distance Indicator [0.03%]
光学重力透镜实验：红团簇星作为距离指示器
A Udalski
A Udalski
We present relation of the mean I-band brightness of red clump stars on metallicity. Red clump stars were proposed to be a very attractive standard candle for distance determination. The calibration is based on 284 nearby red giant stars wh...
R Brada,M Milgrom
R Brada
There is an effect in the modified dynamics that is conducive to the formation of warps. Because of the nonlinearity of the theory, the internal dynamics of a galaxy is affected by a perturber over and above possible tidal effects. For exam...
J Koda,Y Sofue,K Wada
J Koda
We investigate the origin of a unified scaling relation in spiral galaxies. Observed spiral galaxies are spread on a plane in the three-dimensional logarithmic space of luminosity L, radius R, and rotation velocity V. The plane is expressed...
MA Nowak,J Chiang
MA Nowak
The bright Seyfert 1 galaxy MCG -6-30-15 shows large variability on a variety of timescales. We study the less, similar3 day timescale variability using a set of simultaneous archival observations that were obtained from the Rossi X-Ray Tim...