English
Related papers

Related papers: Galactic interstellar sulfur isotopes: A radial $^…

200 papers

Known bright S stars, recognized as such by their enhanced s-process abundances and C/O ratio, are typically members of the asymptotic giant branch (AGB) or the red giant branch (RGB). Few modern digital spectra for these objects have been…

Solar and Stellar Astrophysics · Physics 2015-05-28 Elizabeth Otto , Paul J Green , Richard O. Gray

CONTEXT: The chemistry in the inner few thousand AU of accreting envelopes around young stellar objects is predicted to vary greatly with far-UV and X-ray irradiation by the central star. Aim We search for molecular tracers of high-energy…

Aliphatic hydrocarbons exhibit an absorption feature at 3.4 micron observed toward sources that sample diffuse regions of the interstellar medium. The absorbers responsible for this feature are assumed to reside in some component of…

We have surveyed 401 color selected IRAS sources in the Galactic disk in the SiO J=1--0 v= 1 and 2 maser lines at 43 GHz, resulting in 254 (239 new) detections. The observed sources lie mostly in a strip of the inner Galactic disk with…

Astrophysics · Physics 2015-06-24 S. Deguchi , T. Fujii , I. S. Glass , H. Imai , Y. Ita , H. Izumiura , O. Kameya , A. Miyazaki , Y. Nakada , J. Nakashima

Spectra from MDM Observatory are used to assess Lick/IDS feature strength gradients inside the half-light radius of the compact Local Group elliptical galaxy M32. All but a few (of 24 measured) indices show a statistically significant…

Astrophysics · Physics 2009-11-10 Guy Worthey

We present submillimeter observations of the Local Group, metal-poor, irregular dwarf galaxy IC 10, directly relevant to the interaction between interstellar medium and star formation activity in primeval galaxies. Using the JCMT, we have…

The [NII] 122 and 205 \mu m transitions are powerful tracers of the ionized gas in the interstellar medium. By combining data from 21 galaxies selected from the Herschel KINGFISH and Beyond the Peak surveys, we have compiled 141 spatially…

Following from our recent work, we present a detailed analysis of star-formation and interstellar medium (ISM) scaling relations, done on a representative sample of nearby galaxies. H$\alpha$ images are analysed in order to derive the…

Astrophysics of Galaxies · Physics 2024-01-12 Bogdan A. Pastrav

In the interstellar medium carbon exists in the form of two stable isotopes $^{12}$C and $^{13}$C and their ratio is a good indicator of nucleosynthesis in galaxies. However, chemical fractionation can potentially significantly alter this…

Astrophysics of Galaxies · Physics 2020-08-13 Serena Viti , Francesco Fontani , Izaskun Jimenez-Serra

As part of the Selected Areas Starcount Survey (SASS), a CCD survey to V>21, we have obtained VI photometry of two fields at b=+-40 aligned roughly with an extrapolation of the major axis of the Sagittarius (Sgr) dwarf spheroidal galaxy.…

We aim to better understand the emission of molecular tracers of the diffuse and dense gas in giant molecular clouds and the influence that metallicity, optical extinction, density, far-UV field, and star formation rate have on these…

We present spectra of the extended 12CO and 13CO J=1-0 emission along the major axes of 17 nearby galaxies. Spatial variations in the ratio of CO and 13CO integrated intensities, R, are found in nearly every galaxy observed. There is an…

We present the results of N-band spectro-interferometric observations of the silicate carbon star IRAS08002-3803 with the MID-infrared Interferometric instrument (MIDI) at the Very Large Telescope Interferometer (VLTI) of the European…

The Hipparcos orbiting observatory has revealed a large number of helium-core-burning "clump" stars in the Galactic field. These low-mass stars exhibit signatures of extra-mixing processes that require modeling beyond the first dredge-up of…

Solar and Stellar Astrophysics · Physics 2015-05-19 G. Tautvaisiene , B. Edvardsson , E. Puzeras , G. Barisevicius , I. Ilyin

Electron fraction and cosmic-ray ionization rates (CRIR) in star-forming regions are important quantities in astrochemical modeling and are critical to the degree of coupling between neutrals, ions, and electrons, which regulates the…

We use an underground counting lab with an extremely low background to perform an activity measurement for the $^{12}$C+$^{13}$C system with energies down to $E\rm_{c.m.}$=2.323 MeV, at which the $^{12}$C($^{13}$C,$p$)$^{24}$Na cross…

We present high resolution large scale observations of the molecular and atomic gas in the Local Group Galaxy M33. The observations were carried out using the HERA at the 30m IRAM telescope in the CO(2-1) line achieving a resolution of…

The aim of this paper is to investigate the evolution of the 12C/13C ratio along the AGB through the circumstellar 12CO/13CO ratio. This is the first time a sample including a significant number of M- and S-type stars is analysed together…

Solar and Stellar Astrophysics · Physics 2014-07-02 S. Ramstedt , H. Olofsson

We present highly sensitive measurements taken with MeerKAT at 1280 MHz as well as archival GBT, MWA and VLA images at 333, 88 and 74 MHz. We report the detection of synchrotron radio emission from the infrared dark cloud (IRDC) associated…

High Energy Astrophysical Phenomena · Physics 2023-11-01 F. Yusef-Zadeh , M. Wardle , R. Arendt , J. W. Hewitt , Y. Hu , A. Lazarian , N. Kassim , S. Hyman , I. Heywood

We explore the behaviour of [CII]-157.74um forbidden fine-structure line observed in a sample of 28 galaxies selected from ~50deg^2 of the H-ATLAS survey. The sample is restricted to galaxies with flux densities higher than S_160um>150mJy…