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相关论文: Small-Scale Interstellar Na I Structure Toward M92

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A detailed 3D distribution of interstellar matter in the solar neighborhood is increasingly necessary. As part of a 3D mapping program, we aim at assigning a precise distance to the high-latitude HI gas in particular the northern part (b…

星系天体物理 · 物理学 2015-06-05 Lucky Puspitarini , Rosine Lallement

We report deep, high spectral resolution WSRT HI 21cm observations of four high latitude compact radio sources, that have revealed a new population of tiny, discrete clouds in the diffuse ISM, with peak optical depths tau ~ 0.1-2%, HI…

天体物理学 · 物理学 2009-11-11 Robert Braun , Nissim Kanekar

Na I D absorbing systems toward Type Ia supernovae (SNe Ia) have been intensively studied over the last decade with the aim of finding circumstellar material (CSM), which is an indirect probe of the progenitor system. However, it is…

Optical depth variations in the Galactic neutral interstellar medium (ISM) with spatial scales from hundreds to thousands of astronomical units have been observed through HI absorption against pulsars and continuum sources, while extremely…

We study the properties of low-column density gas clumps in the halo of the Milky Way based on high-resolution 21-cm observations. Using interferometric data from the WSRT and the VLA we study HI emission at low-, intermediate- and high…

星系天体物理 · 物理学 2015-05-13 N. Ben Bekhti , P. Richter , B. Winkel , F. Kenn , T. Westmeier

We report the detection of weak high-velocity Na$\;$I absorption at V$_{\odot}$ = $-61.0\pm0.2$ km s$^{-1}$ in the spectrum of the stellar remnant at the center of the Galactic supernova remnant of 1181 AD. This velocity is not unlike that…

星系天体物理 · 物理学 2026-04-07 Peter Garnavich , Robert A. Fesen

A set of diffuse interstellar clouds in the inner Galaxy within a few hundred pc of the Galactic plane has been observed at an angular resolution of ~1 arcmin combining data from the NRAO Green Bank Telescope and the Very Large Array. At…

星系天体物理 · 物理学 2015-06-15 Yurii Pidopryhora , Felix J. Lockman , John M. Dickey , Michael P. Rupen

We report on a population of absorption systems selected by the presence of very weak Mg II doublets. A sub-population of these systems are iron enriched and have near solar metallicities. This would indicated advanced stages (i.e. few Gyr)…

天体物理学 · 物理学 2007-05-23 Chris Churchill , Jane Rigby , Jane Charlton

Nearby interstellar clouds with high (|v| >/= 10 km/s) random velocities although easily detected in NaI and CaII lines have hitherto not been detected (in emission or absorption) in the HI 21cm line. We describe here deep Giant Metrewave…

天体物理学 · 物理学 2009-11-06 Rekhesh Mohan , K. S. Dwarakanath , G. Srinivasan , Jayaram N. Chengalur

We present high S/N measurements of the H I Ly alpha absorption line toward 16 Galactic targets which are at distances between approximately 190 and 2200 pc, all beyond the wall of the Local Bubble. We describe the models used to remove…

星系天体物理 · 物理学 2023-04-05 S. D. Friedman , P. Chayer , E. B. Jenkins , T. M. Tripp , G. M. Williger , G. Hebrard , P. Sonnentrucker

1.02-1.16 micron spectra (R ~ 7,000) of the gravitationally lensed QSO APM 08279+5255 at z_em=3.911 were obtained during the commissioning run of IRCS, the 1-5 micron near-infrared camera and spectrograph for the Subaru 8.2 m Telescope.…

天体物理学 · 物理学 2009-11-07 Naoto Kobayashi , Hiroshi Terada , Miwa Goto , Alan Tokunaga

(Abridged) We present high-resolution spectra of the interstellar NaI and CaII absorption lines for 3 early-type stars along the line-of-sight towards the Shajn 147 SNR. These are supplemented with far-UV aborption spectra of HD 36665 and…

天体物理学 · 物理学 2009-11-10 S. Sallmen , B. Y. Welsh

The properties of the interstellar medium (ISM) surrounding a planetary system can impact planetary climate through a number of mechanisms, including changing the size of the astrosphere (one of the major shields for cosmic rays) as well as…

星系天体物理 · 物理学 2015-07-15 Marshall C. Johnson , Seth Redfield , Adam G. Jensen

We present moderately-high resolution echelle observations of the nucleus of NGC 5195, the line of sight to which samples intervening interstellar material associated with the outer spiral arm of M51. Our spectra reveal absorption from…

星系天体物理 · 物理学 2018-06-07 Adam M. Ritchey , George Wallerstein

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 investigation of MgII absorbers characterized as single-cloud weak systems at z~1. We measured column densities and Doppler parameters for MgII and FeII in 15 systems found in HIRES/Keck spectra at 6.6 km/s. Using these…

天体物理学 · 物理学 2016-08-30 Jane R. Rigby , Jane C. Charlton , Christopher W. Churchill

We searched for Na I D1,D2 interstellar absorption lines towards 12 giant stars of the Sgr dwarf spheroidal and 3 stars of the associated globular cluster Terzan 7, observed at high resolution with the UVES spectrograph at the 8.2 m Kueyen…

天体物理学 · 物理学 2009-11-10 S. Monai , P. Bonifacio , L. Sbordone

We present an analysis of moderately high resolution optical spectra obtained for the sight line to CD-23 13777, an O9 supergiant that probes high velocity interstellar gas associated with the supernova remnant W28. Absorption components at…

星系天体物理 · 物理学 2023-05-30 Adam M. Ritchey

In the preceding paper (paper I), we presented HI absorption spectra towards radio sources very close to the lines of sight towards 25 bright stars against which optical absorption spectra had been obtained earlier. In this paper we analyse…

天体物理学 · 物理学 2007-05-23 Jayadev Rajagopal , G. Srinivasan , K. S. Dwarakanath

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…

天体物理学 · 物理学 2008-11-26 D. E. Welty , L. M. Hobbs , J. T. Lauroesch , D. C. Morton , L. Spitzer , D. G. York