X-ray Constraints on the Hot Gas Content of Early-type Galaxies in Virgo

Abstract

We present a systematic study of the diffuse hot gas around early-type galaxies (ETGs) residing in the Virgo cluster, based on archival {\it Chandra} observations. Our representative sample consists of 79 galaxies with low-to-intermediate stellar masses ($M_{\ast }\approx 10^{9-11}{\mathrm{M}}_{\odot }$), a mass range that has not been extensively explored with X-ray observations thus far. We detect diffuse X-ray emission in only eight galaxies and find that in five cases a substantial fraction of the detected emission can be unambiguously attributed to truly diffuse hot gas, based on their spatial distribution and spectral properties. For the individually non-detected galaxies, we constrain their average X-ray emission by performing a stacking analysis, finding a specific X-ray luminosity of $L_{\mathrm{X}}/M_{\ast }\sim 10^{28}\mathrm{erg}{\mathrm{s}}^{-1}{\mathrm{M}}_{\odot }^{-1}$, which is consistent with unresolved stellar populations. The apparent paucity of truly diffuse hot gas in these low- and intermediate-mass ETGs may be the result of efficient ram pressure stripping by the hot intra-cluster medium. However, we also find no significant diffuse hot gas in a comparison sample of 57 field ETGs of similar stellar masses, for which archival {\it Chandra} observations with similar sensitivity are available. This points to the alternative possibility that galactic winds evacuate the hot gas from the inner region of low- and intermediate-mass ETGs, regardless of the galactic environment. Nevertheless, we do find strong morphological evidence for on-going ram pressure stripping in two galaxies (NGC 4417 and NGC 4459). A better understanding of the roles of ram pressure stripping and galactic winds in regulating the hot gas content of ETGs, invites sensitive X-ray observations for a large galaxy sample.

25 pages, 7 figures. Accepted for publication in ApJ. Comments Welcome

References in corpus (17)

• X-ray thermal coronae of galaxies in hot clusters -- ubiquity of embedded mini cooling cores
• The Extended Virgo Cluster Catalog
• Chandra's View of the Ram Pressure Stripped Galaxy M86
• AMUSE-Virgo I. Super-massive black holes in low-mass spheroids
• The Hot Gas Content of Low-Luminosity Early-Type Galaxies and the Implications Regarding Supernova Heating and AGN Feedback
• Universal X-ray emissivity of the stellar population in early-type galaxies: unresolved X-ray sources in NGC 3379
• Chandra Observations of Nuclear Outflows in the Elliptical Galaxy NGC4552 in the Virgo Cluster
• Stripped elliptical galaxies as probes of ICM physics: I. Tails, wakes, and flow patterns in and around stripped ellipticals
• X-ray emission from the stellar population in M32
• Ram Pressure Stripping of Hot Coronal Gas from Group and Cluster Galaxies and the Detectability of Surviving X-ray Coronae
• Large scatter in X-ray emission among elliptical galaxies: correlations with mass of host halo
• Extended X-ray study of M49: the frontier of the Virgo Cluster
• Stripped elliptical galaxies as probes of ICM physics: III. Deep Chandra Observation of NGC 4552 - Measuring the Viscosity of the Intracluster Medium
• Constraining the Physical State of the Hot Gas Halos in NGC 4649 and NGC 5846
• Hot gaseous atmospheres of rotating galaxies observed with XMM-Newton
• Chandra Detection of Intra-cluster X-ray sources in Virgo
• X-ray cavities in the hot corona of the lenticular galaxy NGC~4477

Cited by in corpus (4)

• The hot circumgalactic media of massive cluster satellites in the TNG-Cluster simulation: existence and detectability
• A Virgo Environmental Survey Tracing Ionised Gas Emission (VESTIGE).XII. Ionised gas emission in the inner regions of lenticular galaxies
• Probing the link between quenching and morphological evolution
• The formation channels of multiphase gas in nearby early-type galaxies