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相关论文: The Dearth of Neutral Hydrogen in Galactic Dwarf S…

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We present an analysis of the neutral hydrogen (HI) properties of a fully cosmological hydrodynamical dwarf galaxy, run with varying simulation parameters. As reported by Governato et al. (2010), the high resolution, high star formation…

宇宙学与河外天体物理 · 物理学 2015-05-28 K. Pilkington , B. K. Gibson , F. Calura , A. M. Brooks , L. Mayer , C. B. Brook , G. S. Stinson , R. J. Thacker , C. G. Few , D. Cunnama , J. Wadsley

We investigate the claim that all dwarf spheroidal galaxies (dSphs) reside within halos that share a common, universal mass profile as has been derived for dSphs of the Galaxy. By folding in kinematic information for 25 Andromeda dSphs,…

We present neutral atomic hydrogen (HI) observations using the Robert C. Byrd Green Bank Telescope (GBT) along the lines of sight to 49 dwarf satellite galaxy candidates around eight Local Volume systems (M104, M51, NGC1023, NGC1156,…

Several recent works have reported the detection of an unidentified X-ray line at 3.55~keV, which could possibly be attributed to the decay of dark matter (DM) particles in the halos of galaxy clusters and in the M31 galaxy. We analyze all…

高能天体物理现象 · 物理学 2015-09-10 D. Malyshev , A. Neronov , D. Eckert

The GMRT observations of the HI 21~cm-line emission from 13~nearby dwarf star-forming galaxies are presented. The ranges of star formation rates and stellar masses of the sample galaxies are 0.03 -- 1.7~$M_\odot~{\rm yr}^{-1}$ and 0.04 --…

星系天体物理 · 物理学 2020-09-09 Sumit Jaiswal , Amitesh Omar

We consider an all-sky sample of 1029 Local Volume (LV) galaxies situated within a distance of 11 Mpc. Their majority have precise distances, estimates of hydrogen mass fraction and star-formation rate derived from far-ultraviolet or Halpha…

星系天体物理 · 物理学 2018-07-18 I. D. Karachentsev , E. I. Kaisina , D. I. Makarov

Determining the spatial distribution and intrinsic physical properties of neutral hydrogen on cosmological scales is one of the key goals of next-generation radio surveys. We use the EAGLE galaxy formation simulations to assess the…

The Milky Way (MW) dwarf spheroidal satellite galaxies (dSphs) are particularly intriguing targets to search for gamma rays from Weakly Interacting Massive Particle (WIMP) dark matter (DM) annihilation or decay. They are nearby,…

We present the results of the analysis of deep archival \sat\ observations towards the dwarf spheroidal galaxies Draco, Leo I, Ursa Major II and Ursa Minor in the Milky Way neighbourhood. The X-ray source population is characterized and…

星系天体物理 · 物理学 2015-09-09 L. Manni , A. A. Nucita , F. De Paolis , V. Testa , G. Ingrosso

We present atomic hydrogen (HI) observations using the Robert C. Byrd Green Bank Telescope along the lines-of-sight to 27 low surface brightness (LSB) dwarf galaxy candidates discovered in optical searches around M101. We detect HI…

We use 85 pairs of high resolution LCDM cosmological simulations from the NIHAO project to investigate why in dwarf galaxies neutral hydrogen (HI) linewidths measured at 50% of the peak flux W_50 /2 (from the hydrodynamical simulations)…

星系天体物理 · 物理学 2018-11-28 Aaron A. Dutton , Aura Obreja , Andrea V. Macciò

The Wisconsin H Alpha Mapper has been used to set the first deep upper limits on the intensity of diffuse H alpha emission from warm ionized gas in the Local Group dwarf spheroidal galaxies (dSphs) Draco and Ursa Minor. Assuming a velocity…

天体物理学 · 物理学 2009-11-07 J. S. Gallagher , G. J. Madsen , R. J. Reynolds , E. K. Grebel , T. A. Smecker-Hane

The stellar and neutral hydrogen (HI) mass functions at z~0 are fundamental benchmarks for current models of galaxy evolution. A natural extension of these benchmarks is the two-dimensional distribution of galaxies in the plane spanned by…

星系天体物理 · 物理学 2015-06-23 Natasha Maddox , Kelley M. Hess , Danail Obreschkow , M. J. Jarvis , S. -L. Blyth

Mapping stars and gas in nearby galaxies is fundamental for understanding their growth and the impact of their environment. This issue is addressed by comparing the stellar "edges" of galaxies $D_{\rm stellar}$, defined as the outermost…

Neutral hydrogen (HI) has been detected in the Local Group dwarf spheroidal galaxy Sculptor with the 64 m Parkes single dish and mapped with the Australia Telescope synthesis array. Most of the detected HI is in two clouds \sim 15'-20' away…

天体物理学 · 物理学 2009-10-30 Claude Carignan , Sylvie Beaulieu , Stephanie Cote , Serge Demers , Mario Mateo

We use observations made with the Giant Metrewave Radio Telescope (GMRT) to probe the neutral hydrogen (HI) gas content of field galaxies in the VIMOS VLT Deep Survey (VVDS) 14h field at $z \approx 0.32$. Because the HI emission from…

We present an abundance analysis based on high resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor dwarf spheroidal galaxy. We find [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex and…

宇宙学与河外天体物理 · 物理学 2015-05-19 Judith G. Cohen , Wenjin Huang

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

We use high-resolution cosmological zoom-in simulations from the FIRE project to make predictions for the covering fractions of neutral hydrogen around galaxies at z=2-4. These simulations resolve the interstellar medium of galaxies and…

星系天体物理 · 物理学 2015-06-22 C. -A. Faucher-Giguere , P. F. Hopkins , D. Keres , A. L. Muratov , E. Quataert , N. Murray

We compare star formation in the inner and outer disks of 11 dwarf Irregular galaxies (dIm) within 3.6 Mpc. The regions are identified on GALEX near-UV images, and modeled with UV, optical, and near-IR colors to determine masses and ages. A…

宇宙学与河外天体物理 · 物理学 2015-05-14 Nicholas W. Melena , Bruce G. Elmegreen , Deidre A. Hunter , Lea Zernow