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Related papers: Si K Edge Structure and Variability in Galactic X-…

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When the sulfur element is hyperdoped into crystalline silicon to a supersaturated density of 1020 cm-3, it can enhance the sub-bandgap light absorption of silicon from 0 to 70%, with the antireflection of surface dome structures. On the…

Materials Science · Physics 2015-06-19 Ke-Fan Wang , Shengchun Qu , Yuanxu Wang , Zhanguo Wang

We present a comprehensive survey of CII* absorption detections toward stars within 100 pc in order to measure the distribution of electron densities present in the local interstellar medium (LISM). Using high spectral resolution…

Astrophysics · Physics 2009-11-13 Seth Redfield , Ross E. Falcon

Diffuse interstellar bands (DIBs) hold a lot of information about the state and the structure of the ISM. Structure can most directly be observed by extensive spectroscopic surveys, including surveys of stars where DIBs are especially…

Astrophysics of Galaxies · Physics 2017-05-10 Janez Kos

We report on the detection of a population of weak metal-line absorbers in the halo or nearby intergalactic environment of the Milky Way. Using high-resolution ultraviolet absorption-line spectra of bright QSOs obtained with the Space…

Astrophysics of Galaxies · Physics 2014-11-18 Philipp Richter , Jane C. Charlton , Alessio P. M. Fangano , Nadya Ben Bekhti , Joseph R. Masiero

We present high-resolution (<0.65") optical broad-band images of the edge-on Sb galaxy NGC 891 obtained with the WIYN 3.5-m telescope. These BVR images reveal a complex network of hundreds of dust absorbing structures far from the mid-plane…

Astrophysics · Physics 2009-05-29 J. Christopher Howk , Blair D. Savage

We have investigated the X-ray spectral properties of a sample of 138 X-ray sources detected serendipitously in $XMM-Newton$ observations of the Galactic plane, at an intermediate to faint flux level. We divide our sample into 5 subgroups…

High Energy Astrophysical Phenomena · Physics 2015-06-18 R. S. Warwick , K. Byckling , D. Pérez-Ramírez

We investigate the stellar disk structure of six nearby edge-on spiral galaxies using high-resolution JHKs-band images and 3D radiative transfer models. To explore how mass and environment shape spiral disks, we selected galaxies with…

Astrophysics of Galaxies · Physics 2015-06-23 Andrew Schechtman-Rook , Matthew A. Bershady

A resonant inelastic x-ray scattering study of the electronic structure of the semiconductor cuprous oxide, $\rm Cu_2O$, is reported. When the incident x-ray energy is tuned to the Cu K-absorption edge, large enhancements of the spectral…

Materials Science · Physics 2012-06-18 Young-June Kim , J. P. Hill , H. Yamaguchi , T. Gog , D. Casa

The outstanding demonstration of quantum confinement in Si nanocrystals (Si NC) in a SiC matrix requires the fabrication of Si NC with a narrow size distribution. It is understood without controversy that this fabrication is a difficult…

Applied Physics · Physics 2020-05-18 C. Weiss , M. Schnabel , A. Reichert , P. Löper , S. Janz

(Abridged) We present results for J and Ks near-IR imaging data on a large sample of 88 galaxies drawn from the catalogue of Impey et al. (1996). The near-IR data unveils many features of LSBGs not seen before in the optical. First, a high…

Astrophysics · Physics 2009-11-07 Gaspar Galaz , Julianne Dalcanton , Leopoldo Infante , Ezequiel Treister

We describe an ultraviolet spectroscopic survey of interstellar high-velocity cloud (HVC) absorption in the strong 1206.500 Angstrom line of Si III using the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Because…

Astrophysics of Galaxies · Physics 2015-05-14 Joseph A. Collins , Michael Shull , Mark L. Giroux

We have observed the broad-line radio galaxy Arp 102B with ASCA in order to determine the absorbing column density towards its X-ray source and measure its X-ray spectrum. The ultimate goal was to constrain the properties of the medium…

Astrophysics · Physics 2009-11-07 M. Eracleous , J. P. Halpern , J. C. Charlton

The relationship between the luminescence at 1.9 eV and the absorption bands at 2.0 eV and at 4.8 eV were investigated in a wide variety of synthetic silica samples exposed to different gamma- and beta-ray irradiation doses. We found that…

Materials Science · Physics 2007-05-23 L. Vaccaro , M. Cannas , B. Boizot

Disclosing the structure of disks surrounding Herbig AeBe stars is important to expand our understanding of the formation and early evolution of stars and planets. We aim at revealing the sub-AU disk structure around the 10 Myr old Herbig…

Solar and Stellar Astrophysics · Physics 2015-05-18 M. Benisty , E. Tatulli , F. Menard , M. Swain

Galactic and extra-galactic sources produce X-rays that are often absorbed by molecules and atoms in giant molecular clouds (GMCs), which provides valuable information about their composition and physical state. We mimic this phenomenon…

Astrophysics of Galaxies · Physics 2021-07-21 Itay Gissis , Amnon Fisher , Ehud Behar

We present data for a sample of 45 spiral galaxies over a range of Hubble types, imaged in the near-IR J and K bands. Parameters are calculated describing the bulge, disk and bar K-band light distributions, and we look for correlations…

Astrophysics · Physics 2007-05-23 M. S. Seigar , P. A. James

The nanostructure of hydrogenated amorphous silicon (a Si:H) is studied by a combination of small-angle X-ray (SAXS) and neutron scattering (SANS) with a spatial resolution of 0.8 nm. The a-Si:H materials were deposited using a range of…

Materials Science · Physics 2020-11-04 Eike Gericke , Jimmy Melskens , Robert Wendt , Markus Wollgarten , Armin Hoell , Klaus Lips

Over the last 3 yrs, the Galactic center (GC) region has been monitored with the Chandra X-Ray Observatory. With 11 Chandra observations through 2002 June, the total effective exposure reaches ~590 ks, providing significant photon…

We use JWST/MIRI MRS spectroscopy of a sample of six local obscured type 1.9/2 active galactic nuclei (AGN) to compare their nuclear mid-IR absorption bands with the level of nuclear obscuration traced by X-rays. This study is the first to…

In this paper, we analyse the optical absorption in porous silicon . This is the first attempt to explicitly demonstrate that it is not possible to extract the band gap of such low dimensional nanostructures like porous silicon from a Tauc…

Soft Condensed Matter · Physics 2007-05-23 Shouvik Datta , K. L. Narasimhan