Related papers: Hot Gas and Halos in Elliptical Galaxies
Optically-similar early-type galaxies are observed to have a large and poorly understood range in the amount of hot, X-ray-emitting gas they contain.To investigate the origin of this diversity, we studied the hot gas properties of all 42…
Hot ionized interstellar medium interlinks star formation and stellar feedback processes, redistributing energy, momentum, and material throughout galaxies. We use X-ray data from $Chandra$ to extract the hot gas emission from 78 of the…
In order to investigate the nature and origin of dust in elliptical galaxies, a method for the dust mass evaluation, which accounts for the dust temperature distribution, is here presented and discussed. The derived dust masses turn out to…
We present preliminary results from a survey of CO emission from members of a volume-limited sample of non-cluster elliptical galaxies. Our intent is to compare the gas properties of these ellipticals to a sample of lenticulars selected…
NGC 4449 is an irregular galaxy with a moderately high star formation activity. The massive stars in NGC 4449 have given rise to many bright HII regions, superbubbles, supergiant shells, and "chimney-like" radial filaments. ROSAT X-ray…
We place general constraints on the luminosity and mass of hot X-ray emitting gas residing in extended "hot halos" around nearby massive galaxies. We examine stacked images of 2165 galaxies from the 2MASS Very Isolated Galaxy Catalog…
Elliptical galaxies comprise primarily old stars, which collectively generate a long-lasting feedback via stellar mass-loss and Type Ia SNe. This feedback can be traced by X-ray-emitting hot gas in and around such galaxies, in which little…
In order to constrain parameters in galaxy formation theories, especially those for a star formation process, we investigate cold gas in elliptical galaxies. We calculate the detection rate of cold gas in them using a semi-analytic model of…
The enormous range of X-ray luminosities among elliptical galaxies with similar optical luminosities can be attributed to large scatter and systematic variations in the dark halo mass determined from X-ray observations. The mean halo mass…
A hot phase of the interstellar medium has now been detected and studied in several objects through its X-ray emission. A proper assessment of its characteristics is relevant for our understanding of several aspects of galaxy properties,…
Studies of the physical properties of local elliptical galaxies (e.g., gas temperatures, halo masses, stellar kinematics) are shedding new light on galaxy formation. Here we present the hot X-ray gas properties of 33 early-type systems…
X-ray emitting atmospheres of non-rotating early-type galaxies and their connection to central active galactic nuclei have been thoroughly studied over the years. However, in systems with significant angular momentum, processes of heating…
X-ray emission from hot (T = 10^7 K) interstellar gas in massive elliptical galaxies indicates that 10^{10} M_sun has cooled over a Hubble time, but optical and radio evidence for this cold gas is lacking. We provide detailed theoretical…
I will present predictions from chemical evolution model aimed at a self-consistent study of both optical (i.e. stellar) and X-ray (i.e.gas) properties of present-day elliptical galaxies. Detailed cooling and heating processes in the…
Elliptical galaxies have hot coronae with X-ray luminosities and mean gas temperatures that span over wide ranges. This variation can be partially due to the energy budget of the hot gas, that depends on the host galaxy structure and…
The temperature of hot interstellar gas at large radii in elliptical galaxies can be lower than the mean galactic virial temperature. If so, a nonlinear cooling wave can form in the hot interstellar gas and propagate slowly toward the…
We have analyzed Chandra observations of 18 low-luminosity early-type galaxies with L_B < 3 x 10e10 Lo. Thermal emission from hot gas with temperatures between 0.2 and 0.8 keV comprises 5-70% of the total 0.5-2.0 keV emission from these…
We describe two-dimensional gasdynamical computations of the X-ray emitting gas in the rotating elliptical galaxy NGC 4649 that indicate an inflow of about one solar mass per year at every radius. Such a large instantaneous inflow cannot…
I review the current understanding of the origin and nature of ``warm'' ionized gas in giant elliptical galaxies in the light of results of recent imaging and spectroscopic surveys. CCD imaging surveys have revealed that emission-line disks…
I review recent results from our deep ROSAT and Chandra observations of two galaxies, M101 and NGC 4631, in fields of exceptionally low Galactic extinction. Large amounts of X-ray-emitting gas are detected in these galaxies. Such gas is…