Pinning down the ram-pressure-induced halt of star formation in the Virgo cluster spiral galaxy NGC 4388

AbstractWe present VLA 21-cm observations of the spiral galaxy ESO 481-G017 to determine the nature of remote star formation traced by an Hii region found 43 kpc and ∼800 km s−1 from the galaxy center (in projection). ESO 481-G017 is found to have a 120 kpc Hi disk with a mass of 1.2 × 1010M⊙ and UV GALEX images reveal spiral arms extending into the gaseous disk. Two dwarf galaxies with Hi masses close to 108M⊙ are detected at distances of ∼200 kpc from ESO 481-G017 and a Hi cloud with a mass of 6 × 107M⊙ is found near the position and velocity of the remote Hii region. The Hii region is somewhat offset from the Hi cloud spatially and there is no link to ESO 481-G017 or the dwarf galaxies. We consider several scenarios for the origin of the cloud and Hii region and find the most likely is a dwarf galaxy that is undergoing ram pressure stripping. The Hi mass of the cloud and Hi luminosity of the Hii region (1038.1 erg s−1) are consistent with dwarf galaxy properties, and the stripping can trigger the star formation as well as push the gas away from the stars.

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Pre-peak ram pressure stripping in the Virgo cluster spiral galaxy NGC 4501

Astronomy and Astrophysics ◽

10.1051/0004-6361:20078139 ◽

2008 ◽

Vol 483 (1) ◽

pp. 89-106 ◽

Cited By ~ 38

Author(s):

B. Vollmer ◽

M. Soida ◽

A. Chung ◽

J. H. van Gorkom ◽

K. Otmianowska-Mazur ◽

...

Keyword(s):

Spiral Galaxy ◽

Virgo Cluster ◽

Ram Pressure

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A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE)

Astronomy and Astrophysics ◽

10.1051/0004-6361/201833914 ◽

2018 ◽

Vol 620 ◽

pp. A164 ◽

Cited By ~ 8

Author(s):

A. Boselli ◽

M. Fossati ◽

G. Consolandi ◽

P. Amram ◽

C. Ge ◽

...

Keyword(s):

Star Formation ◽

Galaxy Evolution ◽

Narrow Band ◽

Virgo Cluster ◽

X Rays ◽

Environmental Survey ◽

North West ◽

The North ◽

Ram Pressure ◽

The Galaxy

We observed the late-type peculiar galaxy NGC 4424 during the Virgo Environmental Survey Tracing Galaxy Evolution (VESTIGE), a blind narrow-band Hα+[NII] imaging survey of the Virgo cluster carried out with MegaCam at the Canada-French-Hawaii Telescope (CFHT). The presence of a ∼110 kpc (in projected distance) HI tail in the southern direction indicates that this galaxy is undergoing a ram pressure stripping event. The deep narrow-band image revealed a low surface brightness (Σ(Hα) ≃ 4 × 10−18 erg s−1 cm−2 arcsec−2) ionised gas tail ∼10 kpc in length extending from the centre of the galaxy to the north-west, thus in the direction opposite to the HI tail. Chandra and XMM X-rays data do not show a compact source in the nucleus or an extended tail of hot gas, while IFU spectroscopy (MUSE) indicates that the gas is photo-ionised in the inner regions and shock-ionised in the outer parts. Medium-resolution (MUSE) and high-resolution (Fabry-Perot) IFU spectroscopy confirms that the ionised gas is kinematically decoupled from the stellar component and indicates the presence of two kinematically distinct structures in the stellar disc. The analysis of the SED of the galaxy indicates that the activity of star formation was totally quenched in the outer disc ∼250–280 Myr ago, while only reduced by ∼80% in the central regions. All this observational evidence suggests that NGC 4424 is the remnant of an unequal-mass merger that occurred ≲500 Myr ago when the galaxy was already a member of the Virgo cluster, and is now undergoing a ram pressure stripping event that has removed the gas and quenched the activity of star formation in the outer disc. The tail of ionised gas probably results from the outflow produced by a central starburst fed by the collapse of gas induced by the merging episode. This outflow is sufficiently powerful to overcome the ram pressure induced by the intracluster medium on the disc of the galaxy crossing the cluster. This analysis thus suggests that feedback can participate in the quenching process of galaxies in high-density regions.

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Ram pressure stripping of the multiphase ISM in the Virgo cluster spiral galaxy NGC 4438

Astronomy and Astrophysics ◽

10.1051/0004-6361/200811140 ◽

2009 ◽

Vol 496 (3) ◽

pp. 669-675 ◽

Cited By ~ 35

Author(s):

B. Vollmer ◽

M. Soida ◽

A. Chung ◽

L. Chemin ◽

J. Braine ◽

...

Keyword(s):

Spiral Galaxy ◽

Virgo Cluster ◽

Ram Pressure

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Ram pressure stripping of the multiphase ISM and star formation in the Virgo spiral galaxy NGC 4330

Astronomy and Astrophysics ◽

10.1051/0004-6361/201117680 ◽

2012 ◽

Vol 537 ◽

pp. A143 ◽

Cited By ~ 32

Author(s):

B. Vollmer ◽

M. Soida ◽

J. Braine ◽

A. Abramson ◽

R. Beck ◽

...

Keyword(s):

Star Formation ◽

Spiral Galaxy ◽

Ram Pressure

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Two uneven sisters

Astronomy and Astrophysics ◽

10.1051/0004-6361/201731910 ◽

2018 ◽

Vol 620 ◽

pp. A108

Author(s):

B. Vollmer ◽

C. Pappalardo ◽

M. Soida ◽

A. Lançon

Keyword(s):

Spiral Galaxy ◽

Galactic Disk ◽

Pressure Profile ◽

Galactic Structure ◽

Virgo Cluster ◽

Radio Continuum ◽

Continuum Emission ◽

Free Region ◽

Ram Pressure ◽

The Galaxy

Since the Virgo cluster is the closest galaxy cluster in the northern hemisphere, galaxy interactions can be observed in it at kiloparsec resolution. The spiral galaxy NGC 4388 underwent a ram-pressure stripping event ∼200 Myr ago caused by its highly eccentric orbit within the Virgo cluster. This galaxy fulfills all diagnostic criteria for having undergone active ram-pressure stripping in the recent past: it has a strongly truncated HI and Hα disk, an asymmetric ridge of polarized radio continuum emission, extended extraplanar gas toward the opposite side of the ridge of polarized radio continuum emission, and has undergone a recent (a few hundred million years ago) quenching of its star formation activity in the outer, gas-free galactic disk. We made dynamical simulations of the ram-pressure stripping event to investigate the influence of galactic structure on the observed properties of NGC 4388. The combination of a deep optical spectrum of the outer gas-free region of the galactic disk together with deep HI, Hα, far-ultraviolet, and polarized radio continuum data allows us to constrain numerical simulations to derive the temporal ram-pressure profile, the three-dimensional velocity vector of the galaxy, and the time since peak ram pressure with a high level of confidence. From the simulations, an angle between the ram-pressure wind and the galactic disk of 30° is derived. The galaxy underwent peak ram pressure ∼240 Myr ago. The observed asymmetries in the disk of NGC 4388 are not caused by the present action of ram pressure, but by the resettling of gas that has been pushed out of the galactic disk during the ram-pressure stripping event. For the detailed reproduction of multi-wavelength observations of a spiral galaxy that undergoes or underwent a ram-pressure stripping event, galactic structure, such as spiral arms for example, must be taken into account.

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A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE). VIII. Modeling ram pressure stripping of diffuse gas in the Virgo cluster spiral galaxy NGC 4330

Astronomy and Astrophysics ◽

10.1051/0004-6361/202038507 ◽

2020 ◽

Author(s):

B. Vollmer ◽

M. Fossati ◽

A. Boselli ◽

M. Soida ◽

S. Gwyn ◽

...

Keyword(s):

Spiral Galaxy ◽

Virgo Cluster ◽

Gas Emission ◽

Environmental Survey ◽

Ram Pressure

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Morphometry as a probe of the evolution of jellyfish galaxies: evidence of broadening in the surface brightness profiles of ram-pressure stripping candidates in the multicluster system A901/A902

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3226 ◽

2020 ◽

Vol 500 (1) ◽

pp. 40-53

Author(s):

Fernanda Roman-Oliveira ◽

Ana L Chies-Santos ◽

Fabricio Ferrari ◽

Geferson Lucatelli ◽

Bruno Rodríguez Del Pino

Keyword(s):

Star Formation ◽

Surface Brightness ◽

Quantitative Measurement ◽

Star Formation Rate ◽

Hubble Space Telescope ◽

Formation Rate ◽

Structural Evolution ◽

Star Forming ◽

Irregular Structures ◽

Ram Pressure

ABSTRACT We explore the morphometric properties of a group of 73 ram-pressure stripping candidates in the A901/A902 multicluster system, at z∼ 0.165, to characterize the morphologies and structural evolution of jellyfish galaxies. By employing a quantitative measurement of morphometric indicators with the algorithm morfometryka on Hubble Space Telescope (F606W) images of the galaxies, we present a novel morphology-based method for determining trail vectors. We study the surface brightness profiles and curvature of the candidates and compare the results obtained with two analysis packages, morfometryka and iraf/ellipse on retrieving information of the irregular structures present in the galaxies. Our morphometric analysis shows that the ram-pressure stripping candidates have peculiar concave regions in their surface brightness profiles. Therefore, these profiles are less concentrated (lower Sérsic indices) than other star-forming galaxies that do not show morphological features of ram-pressure stripping. In combination with morphometric trail vectors, this feature could both help identify galaxies undergoing ram-pressure stripping and reveal spatial variations in the star formation rate.

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