VLA H [CLC][CSC]i[/CSC][/CLC] Imaging of the Brightest Spiral Galaxies in Coma

Bravo-Alfaro, H.; Cayatte, V.; Gorkom, J. H. van; Balkowski, C.

doi:10.1086/301194

Cited by 186 publications

(232 citation statements)

References 47 publications

Supporting

Mentioning

211

Contrasting

Order By: Relevance

“…It shows furthermore that non-detected spiral galaxies between 0.4 R A and 1.0 R A also exhibit H i deficiencies. The observed trend is similar to that seen in the Coma cluster within 0.4 R A (Bravo-Alfaro et al 2000) and to other massive, X-ray bright galaxy clusters within 1.0 R A (Giovanelli & Haynes 1985).…”

Section: Discussionsupporting

confidence: 84%

Parkes H I observations of galaxies behind the southern Milky Way

Schroeder

Kraan-Korteweg

Henning

2009

A&A

View full text Add to dashboard Cite

As part of our programme to map the large-scale distribution of galaxies behind the southern Milky Way, we observed 314 opticallyselected, partially-obscured galaxies in the Zone of Avoidance (ZOA) in the Crux and Great Attractor (GA) regions. An additional 29 galaxies were observed in the Vela ZOA survey region (because of the small numbers they are not discussed any further). The observations were conducted with the Parkes 64 m (210 ft) radio telescope, in a single-pixel pointed mode, reaching an rms noise level of typically 2−6 mJy over the velocity search range of 400 < v < 10 500 km s −1 . A total of 162 galaxies were detected (plus 14 galaxies in the Vela region). The detection rate is slightly higher than for the Hydra/Antlia region (52% versus 45%) observed in the same way. This can be explained by the prominence of the GA overdensity in the survey regions, which leads to a relatively higher fraction of nearby galaxies. It is also evident from the quite narrow velocity distribution (largely confined to 3000−6000 km s −1 ) and deviates significantly from the expectation of a uniform galaxy distribution for the given sensitivity and velocity range. No systematic differences were found between detections and non-detections, in terms of latitude, foreground extinction, or environment, except for the very central part of the rich Norma cluster, where hardly any galaxies were detected. A detailed investigation of the H i content of the galaxies reveals strong H i deficiency at the core of the Norma cluster (within about a 0.4 Abell radius), similar to what has been found in the Coma cluster. The redshifts obtained by this observing technique result in a substantial reduction of the so-called redshift ZOA. This is obvious when analysing the large-scale structure of the new H i data in combination with data from other (optical) ZOA redshift surveys. The lower latitude detections provide further evidence of the extension of the Norma Wall, across the ZOA, in particular its bending towards the Cen-Crux clusters above the Galactic plane at slightly higher redshift, rather than a straight continuation towards the Centaurus clusters.

show abstract

Section: Discussionsupporting

confidence: 84%

Parkes H I observations of galaxies behind the southern Milky Way

Schroeder

Kraan-Korteweg

Henning

2009

A&A

View full text Add to dashboard Cite

show abstract

“…It represents the neutral gas with the highest column density. The lower resolution map obtained by Bravo-Alfaro et al (2000) shows that the emission extends northwards. In Fig.…”

Section: H Imentioning

confidence: 88%

“…It has been extensively studied at several wavelengths (Hi 21 cm: Giovanelli & Haynes 1985;Gavazzi 1987Gavazzi , 1989Bravo-Alfaro et al 2000;CO: Casoli et al 1991;optical: Colless & Dunn 1996;Biviano et al 1996; Hα: Amram et al 1992; UV: Donas et al 1995, X-rays: Briel et al 1992White et al 1993;Vikhlinin et al 1997) resulting in a detailed view of this cluster.…”

Section: For the Comamentioning

confidence: 99%

$\mathsf{^{12}}$CO(1-0) observations of NGC 4848: A Coma galaxy after stripping

Vollmer

Braine

Balkowski

et al. 2001

A&A

Self Cite

View full text Add to dashboard Cite

Abstract.We study the molecular gas content and distribution in the Coma cluster spiral galaxy NGC 4848 which is Hi deficient and where the remaining atomic gas is on one side of the galaxy, presumably because of the strong ram-pressure in the rich Coma cluster. Plateau de Bure interferometric CO(1-0) observations reveal a lopsided H2 distribution with an off-center secondary maximum coincident with the inner part of the Hi. NGC 4848 is not at all deficient in molecular gas as it contains MH 2 ∼ 4 × 10 9 M in the central and inner disk regions. As predicted by earlier calculations, ram-pressure has little influence on the dense molecular gas in the inner disk, which appears dynamically normal at our 2 kpc resolution. At the interface between the CO and Hi emission regions, about 8 kpc NW of the center, however, strong star formation is present as witnessed by Hα and radio continuum emission. From the radio and Hα fluxes we estimate the star formation rate in the northern emission region to be close to 0.3 M yr −1 , nearly that of an average quiescent spiral. This is the region in which earlier Fabry-Pérot observations revealed a double-peaked Hα line, indicating gas at two different velocities at the same sky position. In order to understand these observations, we present the results of numerical simulations of the galaxy-cluster ICM interaction. We suggest that NGC 4848 already passed through the center of the cluster about 4× 10 8 years ago. At the observed stage ram pressure has no more direct dynamical influence on the galaxy's ISM. We observe the galaxy when a fraction of the stripped gas is falling back onto the galaxy. Ram pressure is thus a short-lived event with longer-lasting consequences. The combination of ram-pressure and rotation results in gas at different velocities colliding where the double-peaked Hα line is observed. Ram-pressure can thus result, after re-accretion, in displaced molecular gas without the H2 itself being pushed efficiently by the intracluster medium. This process, however, requires strong stripping, such that only galaxies with radial orbits can be affected as much as NGC 4848. A scenario where two interactions take place simultaneously is also consistent with the available data but less probable on the basis of our numerical simulations.

show abstract

“…These studies have shown that galaxies in the dense cluster environment tend to be H I deficient (e.g. Sullivan et al 1981;Haynes & Giovanelli 1984;Bravo-Alfaro et al 2000;Solanes et al 2001), and that the distribution of H I mass in galaxies, formulated in the H I mass function, likely evolves with environment (Rosenberg & Schneider 2002;Springob et al 2005).…”

Section: Introductionmentioning

confidence: 99%

Evolution in the H I Gas Content of Galaxy Groups: Pre-Processing and Mass Assembly in the Current Epoch

2013

View full text Add to dashboard Cite

We present an analysis of the neutral hydrogen (H I) content and distribution of galaxies in groups as a function of their parent dark matter halo mass. The Arecibo Legacy Fast ALFA survey α.40 data release allows us, for the first time, to study the H I properties of over 740 galaxy groups in the volume of sky common to the Sloan Digital Sky Survey and ALFALFA surveys. We assigned ALFALFA H I detections a group membership based on an existing magnitude/volume-limited SDSS DR7 group/cluster catalog. Additionally, we assigned group "proximity" membership to H I detected objects whose optical counterpart falls below the limiting optical magnitude-thereby not contributing substantially to the estimate of the group stellar mass, but significantly to the total group H I mass. We find that only 25% of the H I detected galaxies reside in groups or clusters, in contrast to approximately half of all optically detected galaxies. Further, we plot the relative positions of optical and H I detections in groups as a function of parent dark matter halo mass to reveal strong evidence that H I is being processed in galaxies as a result of the group environment: as optical membership increases, groups become increasingly deficient of H I rich galaxies at their center and the H I distribution of galaxies in the most massive groups starts to resemble the distribution observed in comparatively more extreme cluster environments. We find that the lowest H I mass objects lose their gas first as they are processed in the group environment, and it is evident that the infall of gas rich objects is important to the continuing growth of large scale structure at the present epoch, replenishing the neutral gas supply of groups. Finally, we compare our results to those of cosmological simulations and find that current models cannot simultaneously predict the H I selected halo occupation distribution for both low and high mass halos.

show abstract

VLA H [CLC][CSC]i[/CSC][/CLC] Imaging of the Brightest Spiral Galaxies in Coma

Cited by 186 publications

References 47 publications

Parkes H I observations of galaxies behind the southern Milky Way

Parkes H I observations of galaxies behind the southern Milky Way

$\mathsf{^{12}}$CO(1-0) observations of NGC 4848: A Coma galaxy after stripping

Evolution in the H I Gas Content of Galaxy Groups: Pre-Processing and Mass Assembly in the Current Epoch

Contact Info

Product

Resources

About