相关论文: High resolution observations of 'dark' neutral hyd…

We present 21 cm observations of a 10 $\times$ 2 degree region in the Virgo cluster, obtained as part of the Arecibo Galaxy Environment Survey. 289 sources are detected over the full redshift range (-2,000 $<$ $v$$_{hel}$ $<$ + 20,000 km/s)…

We report the results of an HI blind survey of 80deg^2 of the Virgo cluster, based on the 08deg < delta < 16 deg strip of ALFALFA, the Arecibo Legacy Fast ALFA Survey. 187 HI sources of high significance are found providing a complete…

Aperture synthesis observations of two HI cloud complexes located in the periphery of the Virgo galaxy cluster are presented. These low HI-mass clouds ($M_{HI}<$ 10$^{9}$) are seen projected on the M region of the western Virgo cluster,…

We present observations of an HI cloud complex most likely located in the Virgo galaxy cluster, first reported by Kent et al. (2007). The complex consists of five clouds, detected in the data set of the ALFALFA extragalactic HI survey at…

The blind HI survey Arecibo Galaxy Environment Survey (AGES) detected several unresolved sources in the Virgo cluster, which do not have optical counterparts in the Sloan Digital Sky Survey. The origin of these dark clouds is unknown. They…

The Arecibo Legacy Fast ALFA survey is in the process of yielding a complete HI dataset of the Virgo Cluster and its environs (Giovanelli et al. 2007, Kent et al., in preparation). Assuming a distance to Virgo of 16.7 Mpc, the minimum…

We present a second catalog of HI sources detected in the Arecibo Legacy Fast ALFA Survey. We report 488 detections over 135 square degrees, within the region of the sky having 22h<RA<03h and +26deg<Dec<+28deg. We present here the…

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…

VIRGOHI21 is an HI source detected in the Virgo Cluster survey of Davies et al. (2004) which has a neutral hydrogen mass of 10^8 M_solar and a velocity width of Delta V_20 = 220 km/s. From the Tully-Fisher relation, a galaxy with this…

Because of its proximity and richness on late-type galaxies, the Virgo cluster has been the subject of numerous studies exploring the effect of the intracluster environment on galaxy evolution. First discovered nearly three decades ago by…

Most detected neutral atomic hydrogen (HI) at low redshift is associated with optically bright galaxies. However, a handful of HI clouds are known which appear to be optically dark and have no nearby potential progenitor galaxies, making…

High sensitivity (rms noise $\sim 0.5$ mJy) 21-cm HI line observations were made of 33 galaxies in the Virgo cluster, using the refurbished Arecibo telescope, which resulted in the detection of 12 objects. These data, combined with the…

We have carried out a fully sampled large area ($4^{\circ} \times 8^{\circ}$) 21cm \HI line survey of part of the Virgo cluster using the Jodrell Bank multi-beam instrument. The survey has a sensitivity some 3 times better than the standard…

We present HI 21cm emission observations of the z ~ 0.00632 sub-damped Lyman-alpha absorber (sub-DLA) towards PG1216+069 made using the Arecibo Telescope and the Very Large Array (VLA). The Arecibo 21cm spectrum corresponds to an HI mass of…

We present the third installment of HI sources extracted from the Arecibo Legacy Fast ALFA extragalactic survey. This dataset continues the work of the Virgo ALFALFA catalog. The catalogs and spectra published here consist of data obtained…

We present 21 cm observations of a 5 x degree region in the Virgo cluster, obtained as part of the Arecibo Galaxy Environment Survey. 13 cluster members are detected, together with 36 objects in the background. We compare and contrast the…

As part of the HI Arecibo Galaxy Environments Survey (AGES) we have observed 5$\times$4 degrees of sky centred on M33, reaching a limiting column density of $\sim 1.5 \times 10^{17}$ cm$^{-2}$ (line width of 10 km s$^{-1}$ and resolution…

Using data from the ALFALFA Arecibo HI survey of galaxies and the Virgo cluster X-ray pressure profiles from XMM-Newton, we investigate the possibility that starless dark HI clumps, also known as "dark galaxies", are supported by external…

The Widefield Arecibo Virgo Extragalactic Survey (WAVES) was an ongoing HI survey of the Virgo Cluster with the Arecibo Observatory's 305m William E. Gordon Telescope at the time of its structural failure. The full 20 square degrees of the…

We present the analysis of the HI content of a sample of early-type galaxies (ETGs) in low-density environments (LDEs) using the data set provided by the Arecibo Legacy Fast ALFA (ALFALFA) survey. We compare their properties to the sample…