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相关论文: CO and HI observations of an enigmatic cloud

200 篇论文

We report the first detection of circumstellar CO in a globular cluster. Observations with ALMA have detected the CO J=3-2 and SiO v=1 J=8-7 transitions at 345 and 344 GHz, respectively, around V3 in 47 Tucanae (NGC 104; [Fe/H] = -0.72…

We consider here the class of compact, isolated, high-velocity HI clouds, CHVCs, which are sharply bounded in angular extent down to a limiting column density of 1.5x10^18 cm^-2. We describe our automated search algorithm and it's…

天体物理学 · 物理学 2007-05-23 W. B. Burton , R. Braun , V. de Heij

We present maps and a catalogue containing the J=1-0 12CO parameters of 29 individual molecular clouds in the second-brightest LMC star formation complex, N11. In the southwestern part of N11, molecular clouds occur in a ring or shell…

We present the results of ALMA-ACA 7 m-array observations in $^{12}$CO($J=2-1$), $^{13}$CO($J=2-1$), and C$^{18}$O($J=2-1$) line emission toward the molecular-gas disk in the Local Group spiral galaxy M33 at an angular resolution of 7".31…

A high latitude HI 21 cm-line absorption survey toward extragalactic sources was recently completed using the Giant Meterwave Radio Telescope (GMRT). A total of 104 sources with mod(b) > 15 deg. and with a 21 cm flux density greater than 1…

天体物理学 · 物理学 2007-05-23 K. S. Dwarakanath

Several neutral species (MgI, SiI, CaI, FeI) have been detected in a weak MgII absorption line system (W_r(2796)~0.15 Angstroms) at z~0.45 along the sightline toward HE0001-2340. These observations require extreme physical conditions, as…

宇宙学与河外天体物理 · 物理学 2015-05-18 Therese M. Jones , Toru Misawa , Jane C. Charlton , Andrew C. Mshar , Gary J. Ferland

We use observations of the neutral atomic hydrogen (HI) 21-cm emission line to study the spatial distribution of the HI gas in a 80$\degree\times~$90$\degree$ region of the Galaxy halo. The HI column densities in the range of…

星系天体物理 · 物理学 2017-09-20 Ericson López , Jairo Armijos , Mario Llerena , Franklin Aldás

We present the analysis of the diffuse, low column density HI environment of 18 MHONGOOSE galaxies. We obtained deep observations with the Robert C. Byrd Green Bank Telescope, and reached down to a 3sigma column density detection limit of…

星系天体物理 · 物理学 2021-04-07 Amy Sardone , D. J. Pisano , N. M. Pingel , Amidou Sorgho , Claude Carignan , W. J. G. de Blok

A population of molecular clouds with a significantly greater scale height than that of Giant Molecular Clouds has been identified by examining maps of the latitude distribution of the $^{12}CO(1-0)$ emission in the first quadrant of the…

天体物理学 · 物理学 2009-10-22 Sangeeta Malhotra

Molecular gas has been searched for and found in unexpectedly large quantities in some collisional debris of interacting galaxies: HI-rich tidal tails, bridges and collisional rings. It was so far observed through millimeter observations of…

天体物理学 · 物理学 2007-10-04 Pierre-Alain Duc

We report about high spatial resolution observations made with the IRAM interferometer of the CO emission from a 1.1x1.1 kpc plane-of-sky field on a spiral arm of Messier 81. With a beam of 5''(90 pc), we identify 6 giant molecular cloud…

天体物理学 · 物理学 2007-05-23 N. Brouillet , M. Kaufman , F. Combes , A. Baudry , F. Bash

Observations of dense molecular gas lie at the basis of our understanding of the density and temperature structure of protostellar envelopes and molecular outflows. We aim to characterize the properties of the protostellar envelope,…

太阳与恒星天体物理 · 物理学 2015-05-14 T. A. van Kempen , E. F. van Dishoeck , M. R. Hogerheijde , R. Guesten

21 cm HI line observations were made with the Arecibo Gregorian telescope of 9 HI clouds in the Hercules Cluster which were reported as tenative detections in a VLA HI study of the cluster (Dickey 1997) and for which our deep CCD imaging…

Understanding stellar birth requires observations of the clouds in which they form. These clouds are dense and self-gravitating, and in all existing observations, they are molecular with H_2 the dominant species and CO the best available…

星系天体物理 · 物理学 2017-03-08 Monica Rubio , Bruce G. Elmegreen , Deidre A. Hunter , Elias Brinks , Juan R. Cortes , Phil Cigan

We investigate the correlation between CO and HI emission in 18 nearby galaxies from the CARMA Survey Toward IR-Bright Nearby Galaxies (STING) at sub-kpc and kpc scales. Our sample, spanning a wide range in stellar mass and metallicity,…

We present a 21cm line HI self-absorption (HISA) survey of cold atomic gas within Galactic longitudes 75 to 146 degrees and latitudes -3 to +5 degrees. We identify HISA as spatially and spectrally confined dark HI features and extract it…

The nucleus of the Milky Way is known to drive a large-scale, multiphase galactic outflow, with gas phases ranging from the hot highly-ionized to the cold molecular component. In this work, we present the first systematic search for…

Context. The transition from the spherically symmetric envelopes around asymptotic giant branch (AGB) stars to the asymmetric morphologies observed in planetary nebulae is still not well understood, and the shaping mechanisms are a subject…

太阳与恒星天体物理 · 物理学 2024-01-17 Jaime Alonso-Hernández , Carmen Sánchez Contreras , Raghvendra Sahai

The amount of H$_2$ present in spiral galaxies remains uncertain, particularly in the dim outer regions and in low-metallicity environments. We present high-resolution CO(1--0) observations with the Plateau de Bure interferometer of the…

星系天体物理 · 物理学 2016-04-20 J. Braine , P. Gratier , Y. Contreras , K. F. Schuster , N. Brouillet

The origin of extragalactic, almost dark HI clouds with extreme gas-to-stellar mass ratios remains poorly understood. We investigate the nature and fate of the "almost dark" cloud AGC 226178, projected within the Virgo cluster, with an…