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Related papers: Boron Abundances in Diffuse Interstellar Clouds

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The ionized core in the Sgr B2 Main star-forming region was imaged using the Submillimeter Array archival data observed for the H26$\alpha$ line and continuum emission at 0.86 millimeter with an angular resolution 0.3\arcsec. Eight…

Solar and Stellar Astrophysics · Physics 2015-05-30 Jun-Hui Zhao , M. C. H. Wright

We report ALMA observations with resolution $\approx0.5$" at 3 mm of the extended Sgr B2 cloud in the Central Molecular Zone (CMZ). We detect 271 compact sources, most of which are smaller than 5000 AU. By ruling out alternative…

As a complement to the HyGAL Stratospheric Observatory for Infrared Astronomy Legacy Program, we report the results of a ground-based absorption line survey of simple molecules in diffuse and translucent Galactic clouds. Using the Institut…

We present an analysis of high resolution HST Space Telescope Imaging Spectrograph (STIS) observations of O I 1356 and H I Lyman-alpha absorption in 36 sight lines that probe a variety of Galactic disk environments and include paths that…

Astrophysics · Physics 2009-11-10 Stefan I. B. Cartledge , J. T. Lauroesch , David M. Meyer , Ulysses J. Sofia

The giant molecular cloud complex, Sgr B2, was observed with the ISO Long Wavelength Spectrometer over the range 47-197 microns. The ground state rotational transitions of OH lie in the survey range and we have analysed results from the…

Astrophysics · Physics 2007-05-23 E. T. Polehampton , J. -P. Baluteau , B. M. Swinyard

We present an extensive analysis of the gas-phase abundances and depletion behaviors of neutron-capture elements in the interstellar medium (ISM). Column densities (or upper limits to the column densities) of Ga II, Ge II, As II, Kr I, Cd…

Astrophysics of Galaxies · Physics 2018-06-07 Adam M. Ritchey , Steven R. Federman , David L. Lambert

The cosmological origin of carbon, the fourth most abundant element in the Universe, is not well known and matter of heavy debate. We investigate the behavior of C/O to O/H in order to constrain the production mechanism of carbon. We…

Astrophysics of Galaxies · Physics 2017-10-04 Maria A. Peña-Guerrero , Claus Leitherer , Selma de Mink , Aida Wofford , Lisa Kewley

Interstellar lines observed toward stellar targets change slowly over long timescales, mainly due to the proper motion of the background target relative to the intervening clouds. On longer timescales, the cloud's slowly changing physical…

Measurements of oxygen abundance throughout galaxies provide insight to the formation histories and ongoing processes. Here we present a study of the gas phase oxygen abundance in the HII regions and diffuse gas of the nearby starburst…

New SiS multi-transition (sub-)millimetre line observations of a sample of AGB stars with varying photospheric C/O-ratios and mass-loss rates are presented. A combination of low- and high-energy lines are important in constraining the…

Astrophysics · Physics 2009-11-13 F. L. Schoeier , J. Bast , H. Olofsson , M. Lindqvist

We report on the abundance of interstellar neutral oxygen (OI) for 26 sightlines, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE), the International Spectroscopic Explorer (IUE), and the Hubble Space Telescope (HST). OI…

Astrophysics · Physics 2009-11-10 Adam G. Jensen , Brian L. Rachford , Theodore P. Snow

Elements in the interstellar medium (ISM) exist in the form of gas or dust. The interstellar extinction and elemental abundances provide crucial constraints on the composition, size and quantity of interstellar dust. Most of the extinction…

Astrophysics of Galaxies · Physics 2021-03-17 W. B. Zuo , Aigen Li , Gang Zhao

Spectra obtained with the Hubble Space Telescope GHRS are combined with high-resolution optical spectra and UV spectra from Copernicus to study the abundances and physical conditions in the diffuse interstellar clouds seen along the line of…

Astrophysics · Physics 2008-11-26 D. E. Welty , L. M. Hobbs , J. T. Lauroesch , D. C. Morton , L. Spitzer , D. G. York

By using the high resolution spectrograph FLAMES@VLT we performed the first systematic campaign devoted to measure chemical abundances of blue straggler stars (BSSs). These stars, whose existence is not predicted by the canonical stellar…

Astrophysics of Galaxies · Physics 2014-01-17 L. Lovisi

We combine observations of spiral galaxies in the [CII] line at 158 micron, made with the Long Wavelength Spectrometer aboard ISO, with previous data from the Kuiper Airborne Observatory to study the origin of this line, which is the main…

Astrophysics · Physics 2009-11-06 D. Pierini , J. Lequeux , A. Boselli , K. J. Leech , H. J. Voelk

Based on our sample of 10095 galaxies with bulge-disc decompositions we derive the empirical B-band internal attenuation--inclination relation for galaxy discs and their associated central bulges. Our results agree well with the…

The observed B/Be ratio in extreme Pop II stars has been interpreted as evidence of Be and B synthesis by early galactic cosmic rays. However, a recent reanalysis of the boron abundance in the Pop II halo star HD140283 suggests that B/H may…

Astrophysics · Physics 2009-09-25 B. Fields , K. Olive , D. Schramm

We present measurements of the oxygen abundance of the Milky Way's ISM by observing the K-shell X-ray photoionization edge towards galaxy clusters. This effect is most easily observed towards objects with galactic columns (n_H) of a few…

Astrophysics · Physics 2009-11-13 Wayne H. Baumgartner , Richard F. Mushotzky

New FUSE far-UV spectroscopy of the nearby metal-deficient (Zsun/8) cometary Blue Compact Dwarf (BCD) galaxy Markarian (Mrk) 59 is discussed. The data are used to investigate element abundances in its interstellar medium. The H I absorption…

Astrophysics · Physics 2007-05-23 T. X. Thuan , A. Lecavelier des Etangs , Y. I. Izotov

Ions (e.g., H$_3^+$, H$_2$O$^+$) have been used extensively to quantify the cosmic-ray ionization rate (CRIR) in diffuse sightlines. However, measurements of CRIR in low-to-intermediate density gas environments are rare, especially when…

Astrophysics of Galaxies · Physics 2023-01-19 Gan Luo , Zhi-Yu Zhang , Thomas G. Bisbas , Di Li , Ningyu Tang , Junzhi Wang , Ping Zhou , Pei Zuo , Nannan Yue , Jing Zhou , Lingrui Lin