中文
相关论文

相关论文: Si K Edge Structure and Variability in Galactic X-…

200 篇论文

Diffuse X-rays from the Galactic center (GC) region were found to exhibit many K-shell lines from iron and nickel atoms in the 6--9 keV band. The strong emission lines seen in the spectrum are neutral iron K$\alpha$ at 6.4~keV, He-like iron…

高能天体物理现象 · 物理学 2010-07-29 T. G. Tsuru , H. Uchiyama , M. Nobukawa , M. Sawada , S. G. Ryu , R. Fukuoka , K. Koyama

We use molecular dynamics computer simulations to study the equilibrium properties of the surface of amorphous silica. Two types of geometries are investigated: i) clusters with different diameters (13.5\AA, 19\AA, and 26.5\AA) and ii) a…

统计力学 · 物理学 2009-10-31 Alexandra Roder , Walter Kob , Kurt Binder

In the framework of the silicate core-carbonaceous organic mantle interstellar dust model, the bulk of the visual/near-IR extinction and the entire polarization are from nonspherical and aligned core-mantle grains. The 3.4 micron C-H and…

天体物理学 · 物理学 2009-11-07 Aigen Li , J. Mayo Greenberg

The dense Galactic environment is a large reservoir of interstellar dust. Therefore, this region represents a perfect laboratory to study the properties of the cosmic dust grains. X-rays are the most direct way to detect the interaction of…

To understand the origin of extended disks of low-surface brightness (LSB) galaxies, we studied in detail 4 such systems with large disks seen edge-on. Two of them are edge-on giant LSB galaxies (gLSBGs) recently identified by our team. The…

We use photometric and spectroscopic infrared observations obtained with the Spitzer Space Telescope of 12 radio-loud active galactic nuclei (AGN) to investigate the dust geometry. Our approach is to look at the change of the infrared…

宇宙学与河外天体物理 · 物理学 2015-05-19 Hermine Landt , Catherine L. Buchanan , Pauline Barmby

We present a computational study of small-angle X-ray scattering (SAXS) in amorphous silicon ($a$-Si) with particular emphasis on the morphology and microstructure of voids. The relationship between the scattering intensity in SAXS and the…

无序系统与神经网络 · 物理学 2018-05-23 Durga Paudel , Raymond Atta-Fynn , David A. Drabold , Stephen R. Elliott , Parthapratim Biswas

We investigate the silicate feature of the two Class I components of HH250-IRS, a resolved binary system with a separation of $0''53$ driving a Herbig-Haro flow. Each component has its own circumstellar envelope, and the system is…

太阳与恒星天体物理 · 物理学 2019-08-21 F. Comerón , B. Merin , B. Reipurth , H. -W. Yen

We present the first comprehensive analysis of the argon K-edge absorption region (3.1-4.2 \AA) using high-resolution HETGS {\it Chandra} spectra of 33 low-mas X-ray binaries. Utilizing R-matrix theory, we computed new K photoabsorption…

高能天体物理现象 · 物理学 2024-09-25 E. Gatuzz , T. W. Gorczyca , M. F. Hasoglu , J. A. García , T. R. Kallman

Absorption lines in the spectra of distant quasars whose sightlines pass through foreground galaxies provide a valuable tool to probe the dust and gas compositions of the interstellar medium (ISM) in galaxies. The first evidence of silicate…

星系天体物理 · 物理学 2014-05-05 Monique C. Aller , Varsha P. Kulkarni , Donald G. York , Daniel E. Welty , Giovanni Vladilo , Debopam Som

High resolution X-ray spectra of the Reflection Grating Spectrometer (RGS) on board the XMM satellite are used to resolve the oxygen K absorption edge. By combining spectra of low and high extinction sources, the observed absorption edge…

Spectroscopy at 8-13 microns with T-ReCS on Gemini-S is presented for 3 galaxies with substantial silicate absorption features, NGC 3094, NGC 7172 and NGC 5506. In the galaxies with the deepest absorption bands, the silicate profile towards…

天体物理学 · 物理学 2008-11-26 P. F. Roche , C. Packham , D. K. Aitken , R. E. Mason

We present K-band imaging of fields around 30 strong CaII absorption line systems, at 0.7<z<1.1, three of which are confirmed Damped Lyman-alpha systems. A significant excess of galaxies is found within 6"0 (~50kpc) from the absorber…

天体物理学 · 物理学 2009-06-23 Paul Hewett , Vivienne Wild

We present 8-13 micron imaging and spectroscopy of 9 type 1 and 10 type 2 AGN obtained with the VLT/VISIR instrument at spatial resolution <100 pc. The emission from the host galaxy sources is resolved out in most cases. The silicate…

宇宙学与河外天体物理 · 物理学 2015-05-18 S. F. Hoenig , M. Kishimoto , P. Gandhi , A. Smette , D. Asmus , W. Duschl , M. Polletta , G. Weigelt

We study X-ray and soft gamma-ray spectral properties of BLRGs using data from Ginga, ASCA, OSSE and EXOSAT. The X-ray spectra are well fitted by an intrinsic power-law continuum with an energy index of alpha ~ 0.7, moderately absorbed by a…

We report on ASCA energy spectra of Cir X-1 taken near its zero phase on 1994 August 4-5. The ASCA SIS detectors allow a more detailed study of the iron K complex than has been possible before. We find that prior to a sudden upward flux…

天体物理学 · 物理学 2015-06-24 W. N. Brandt , A. C. Fabian , T. Dotani , F. Nagase , H. Inoue , T. Kotani , Y. Segawa

We present the results of the simultaneous deep XMM and Chandra observations of the bright Seyfert 1.9 galaxy MCG-5-23-16, which is thought to have one of the best known examples of a relativistically broadened iron K-alpha line. The time…

The 9.7-micron silicate absorption profile in the interstellar medium provides important information on the physical and chemical composition of interstellar dust grains. Measurements in the Milky Way have shown that the profile in the…

星系天体物理 · 物理学 2015-06-24 P. F. Roche , A. Alonso-Herrero , O. Gonzalez-Martin

We study the population of low-mass X-ray binaries (LMXBs) in the Galactic bulge using the deep survey of this region by the IBIS telescope aboard the INTEGRAL observatory. Thanks to the increased sensitivity with respect to previous…

天体物理学 · 物理学 2009-11-13 M. Revnivtsev , A. Lutovinov , E. Churazov , S. Sazonov , M. Gilfanov , S. Grebenev , R. Sunyaev

We present new L-band ($1\mbox{--}2$ GHz) observations of the nearby spiral galaxy M33 with 80 pc resolution obtained with the Karl G. Jansky Very Large Array. The HI observations, combined with HI measurements from the Green Bank…