English
Related papers

Related papers: A polycrystalline graphite model for the 2175 Angs…

200 papers

Interstellar diffuse bands are usually extracted from hot star spectra because they are characterized by smooth continua. It introduces a strong limitation on the number of available targets, and reduces potential studies of the IS matter…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Hui-Chen Chen , Rosine Lallement , Carine Babusiaux , Lucky Puspitarini , Piercarlo Bonifacio , Vanessa Hill

We have obtained new STIS/HST spectra to search for structure in the ultraviolet interstellar extinction curve, with particular emphasis on a search for absorption features produced by polycyclic aromatic hydrocarbons (PAHs). The presence…

In this paper we provide a comprehesive analysis of different properties of pnictides both in the normal and superconducting state, with a particular focus on the optimally-doped Ba$_{1-x}$K$_{x}$Fe$_2$As$_2$ system. We show that, by using…

Superconductivity · Physics 2010-01-11 L. Benfatto , E. Cappelluti , C. Castellani

We report the detection of a strong Milky Way-type 2175 \AA$ $ extinction bump at $z$ = 2.1166 in the quasar spectrum towards SDSS J121143.42+083349.7 from the Sloan Digital Sky Survey (SDSS) Data Release 10. We conduct follow up…

We construct a quasar extinction curve based on the blue and red composite quasar spectra of Richards et al. (2003) prepared from the SDSS survey. This extinction curve does not show any traces of the 2200 A feature characteristic of the…

Astrophysics · Physics 2009-11-10 B. Czerny , J. Li , Z. Loska , R. Szczerba

Particle shape and aggregation have a strong influence on the spectral profiles of infrared phonon bands of solid dust grains. In this paper, we use a discrete dipole approximation, a cluster-of-spheres code following the Gerardy-Ausloos…

Astrophysics · Physics 2007-05-23 Anja C. Andersen , Harald Mutschke , Thomas Posch

The dielectric function of interstellar dust material is modeled using observations of extinction and polarization in the infrared, together with estimates for the mass of interstellar dust. The "astrodust" material is assumed to be a mix…

Astrophysics of Galaxies · Physics 2021-03-17 B. T. Draine , Brandon S. Hensley

Cosmic infrared emission and absorption spectra often carry a well-defined and invariant 6.2 micron band that has been proposed to emanate from very small dust grains that may carry polyaromatic hydrocarbons. Hemoglycin, a well-defined…

Astrophysics of Galaxies · Physics 2024-04-01 Julie E. M. McGeoch , Malcolm W. McGeoch

Modern data of the extinction curve from the ultraviolet to the near infrared are revisited to study the property of dust grains in the Milky Way (MW) and the Small Magellanic Cloud (SMC). We confirm that the graphite-silicate mixture of…

Astrophysics of Galaxies · Physics 2015-06-12 Takaya Nozawa , Masataka Fukugita

The sizes of interstellar grains are widely distributed, ranging from a few angstroms to a few micrometers. The ultraviolet (UV) and optical extinction constrains the dust in the size range of a couple hundredth micrometers to several…

Astrophysics of Galaxies · Physics 2015-09-23 Shu Wang , Aigen Li , B. W. Jiang

We investigate the role of electron-hole correlations in the absorption of freestanding monolayer and bilayer graphene using optical transmission spectroscopy from 1.5 to 5.5 eV. Line shape analysis demonstrates that the ultraviolet region…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 Dong-Hun Chae , Tobias Utikal , Siegfried Weisenburger , Harald Giessen , Klaus. v. Klitzing , Markus Lippitz , Jurgen H. Smet

We present a set of 6-12 micron ISOPHOT-S spectra of the general interstellar medium of the Milky Way. This part of the spectrum is dominated by a series of strong, wide emission features commonly called the Unidentified Infrared Bands. The…

Astrophysics · Physics 2009-11-07 J. Kahanpaa , K. Mattila , K. Lehtinen , C. Leinert , D. Lemke

We consider the optical properties of the half-filled AB-stacked bilayer graphene with the excitonic pairing and condensation between the layers. Both intra and interlayer local Coulomb interaction effects have been taken into account and…

Mesoscale and Nanoscale Physics · Physics 2021-12-15 V. Apinyan , T. K. Kopec

We interpret the interstellar extinction observed towards the Galactic Center (GC) in the wavelength range $\lambda = 1 - 20\,\mkm$. Its main feature is the flat extinction at $3 - 8\,\mkm$ whose explanation is still a problem for the…

Astrophysics of Galaxies · Physics 2017-03-08 Nikolai V. Voshchinnikov , Thomas Henning , Vladimir B. Il'in

A precise measure of the mid-infrared interstellar extinction law is crucial to the investigation of the properties of interstellar dust, especially of the grains in the large size end. Based on the stellar parameters derived from the…

Astrophysics of Galaxies · Physics 2016-11-10 Mengyao Xue , Biwei Jiang , Jian Gao , Jiaming Liu , Shu Wang , Aigen Li

Infrared (IR) emission spectra are calculated for dust composed of mixtures of amorphous silicate and graphitic grains, including varying amounts of polycyclic aromatic hydrocarbon (PAH) particles. The models are constrained to reproduce…

Astrophysics · Physics 2008-11-26 B. T. Draine , Aigen Li

We aim to compare variations in the full-UV dust extinction curve (912-3000 Angstrom), with the HI/H$_2$/total H content along diffuse Milky Way sightlines, to investigate possible connections between ISM conditions and dust properties. We…

Astrophysics of Galaxies · Physics 2023-02-15 Dries Van De Putte , Stefan I. B. Cartledge , Karl D. Gordon , Geoffrey C. Clayton , Julia Roman-Duval

We present a quantitative model for the infrared emission from dust in the diffuse interstellar medium. The model consists of a mixture of amorphous silicate grains and carbonaceous grains, each with a wide size distribution ranging from…

Astrophysics · Physics 2008-11-26 Aigen Li , B. T. Draine

The integral-field unit (IFU) spectrometers on board the James Webb Space Telescope (JWST) undersample the nearly diffraction-limited point spread function provided by the telescope optics. This undersampling produces large oscillating…

Instrumentation and Methods for Astrophysics · Physics 2026-03-31 David R. Law , Melanie Clarke

The 2D Fermi surface of 1st stage PdAl2Cl8 acceptor-type graphite intercalation compounds (GICs) has been investigated using the Shubnikov-de Haas (SdH) effect. One fundamental frequency is observed, the angular variation of which confirms…

Materials Science · Physics 2007-05-23 R. T. F. van Schaijk , A. de Visser , E. McRae , B. Sundqvist , T. Wagberg , R. Vangelisti