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Related papers: AGC198606: A gas-bearing dark matter minihalo?

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Assuming a hydrostatic equilibrium in an HI cloud, the joint Poisson's equation is set up and numerically solved to calculate the expected HI distribution. Unlike previous studies, the cloud is considered to be non-isothermal, and an {\it…

Astrophysics of Galaxies · Physics 2018-08-15 Narendra Nath Patra

The Westerbork Synthesis Radio Telescope finds a weak 21cm line emission feature at the coordinates (RA-Dec-velocity) of the sub-Damped Lyman-alpha absorber observed at z_abs=0.00632 in the spectrum of PG1216+069. The emission feature,…

Astrophysics · Physics 2009-11-11 F. H. Briggs , D. G. Barnes

We report the discovery of Corvus A, a low-mass, gas-rich galaxy at a distance of approximately 3.5 Mpc, identified in DR10 of the Dark Energy Camera Legacy Imaging Survey during the initial phase of our ongoing SEmi-Automated Machine…

Very sensitive 21cm HI measurements have been made at several locations around the Local Group galaxy M31 using the Green Bank Telescope (GBT) at an angular resolution of 9.1', with a 5$\sigma$ detection level of $\rm{N_{HI} = 3.9 \times…

Astrophysics of Galaxies · Physics 2016-01-27 Spencer A. Wolfe , Felix J. Lockman , D. J. Pisano

In this Letter, we announce the discovery of a new dwarf galaxy, Leo T, in the Local Group. It was found as a stellar overdensity in the Sloan Digital Sky Survey Data Release 5 (SDSS DR5). The color-magnitude diagram of Leo T shows two…

We report the discovery by the Arecibo Legacy Fast ALFA (ALFALFA) survey of eight HI features not coincident with stellar counterparts in the Virgo Cluster region. All of the HI clouds have cz < 3000 km/s and, if at the Virgo distance, HI…

The Arecibo Galaxy Environment Survey (AGES) has detected a nearby HI source at a heliocentric velocity of +363 km/s . The object was detected through its neutral hydrogen emission and has an obvious possible optical counterpart in Sloan…

Astrophysics of Galaxies · Physics 2015-06-19 R. Taylor , R. F. Minchin , H. Herbst , R. Smith

Ultra-compact high velocity clouds (UCHVCs) were identified in the ALFALFA HI survey as potential gas-bearing dark matter halos. Here we present higher resolution neutral hydrogen (HI) observations of twelve UCHVCS with the Westerbork…

Astrophysics of Galaxies · Physics 2016-12-21 Elizabeth A. K. Adams , Tom A. Oosterloo , John M. Cannon , Riccardo Giovanelli , Martha P. Haynes

HI observations of the nearby blue compact dwarf galaxy IC 10 obtained with the Dominion Radio Astrophysical Observatory synthesis telescope (DRAO), for a total integration of $\sim$1000 hours, are presented. We confirm the NW faint 21 cm…

Astrophysics of Galaxies · Physics 2020-01-08 Brenda Namumba , Claude Carignan , Tyler Foster , Nathan Deg

In recent years, ultrafaint dwarf (UFD) galaxies have been found through systematic searches of large optical surveys. However, the existence of Leo T, a nearby gas-rich dwarf, suggests that there could be other nearby UFDs that are…

Astrophysics of Galaxies · Physics 2019-07-02 Daniel DeFelippis , Mary Putman , Erik Tollerud

We analyze interstellar absorption features in the full UV spectrum of the nearby (d = 24 pc) B8 IVn star alpha Leo (Regulus) obtained at high resolution and high S/N by the HST ASTRAL Treasury program. We derive column densities for many…

Astrophysics of Galaxies · Physics 2017-02-01 Cecile Gry , Edward B. Jenkins

We present deep optical imaging and photometry of four objects classified as "Almost-Dark" galaxies in the ALFALFA survey because of their gas-rich nature and extremely faint or missing optical emission in existing catalogs. They have HI…

Understanding the distribution of gas in and around galaxies is vital for our interpretation of galaxy formation and evolution. As part of the Arecibo Galaxy Environment Survey (AGES) we have observed the neutral hydrogen (HI) gas in and…

Astrophysics of Galaxies · Physics 2017-03-29 Olivia Keenan , Jonathan Davies , Rhys Taylor , Robert Minchin

The location of two nearby galaxy groups within ~20 Mpc in the Leo region allows for a detailed study of low-mass galaxies. A catalog of HI line detections in Leo (9h36m < RA <11h36m, +8deg < dec < +16deg) has been made from the blind HI…

Astrophysics · Physics 2009-11-13 Sabrina Stierwalt

ESO 149-G003 is a close-by, isolated dwarf irregular galaxy. Previous observations with the ATCA indicated the presence of anomalous neutral hydrogen (HI) deviating from the kinematics of a regularly rotating disc. We conducted follow-up…

The nearby galaxy HIZSS003 was recently discovered during a blind HI survey of the zone of avoidance (Henning et al. 2000). Follow up VLA as well as optical and near-IR imaging and spectroscopy (Massey et al. 2003; Silva et al. 2005)…

Astrophysics · Physics 2009-11-10 Ayesha Begum , Jayaram N. Chengalur , I. D. Karachentsev , M. E. Sharina

We present results from deep HI and optical imaging of AGC 229101, an unusual HI source detected at v$_{\rm helio}$ = 7116 km/s in the ALFALFA survey. Initially classified as a candidate "dark" source because it lacks a clear optical…

A study is presented of HI line observations of the nearby spiral galaxy NGC 3521 observed with the VLA as part of The HI Nearby Galaxy Survey. Clearly evident in the HI data cube is the presence of an anomalous HI component that is both…

Astrophysics of Galaxies · Physics 2013-12-10 Edward Elson

We analyze line-of-sight atomic hydrogen (HI) line profiles of 31 nearby, low-mass galaxies selected from the Very Large Array - ACS Nearby Galaxy Survey Treasury (VLA-ANGST) and The HI Nearby Galaxy Survey (THINGS) to trace regions…

We present spectroscopic observations of the nearby dwarf galaxy AGC 198691. This object is part of the Survey of HI in Extremely Low-Mass Dwarfs (SHIELD) project, which is a multi-wavelength study of galaxies with HI masses in the range of…