相关论文: Discovery of CIV Emission Filaments in M87
The physical relationship between low-excitation gas filaments at ~10^4 K, seen in optical line emission, and diffuse X-ray emitting coronal gas at ~10^7 K in the centers of many galaxy clusters is not understood. It is unclear whether the…
We compare a very deep X-ray image of M87, at the center of the Virgo Cluster, to high-quality optical images of the low excitation emission-line gas in the same region. There are striking coincidences of detail between the two. We explore…
We present a multi-wavelength study of the emission-line nebulae located southeast of the nucleus of M87, the central dominant galaxy of the Virgo Cluster. We report the detection of far-infrared (FIR) [CII] line emission from the nebulae…
We present new HST-COS G130M spectroscopy for a sightline toward a filament projected 1.9 kpc from the nucleus of M87. The combination of the sensitivity of COS and the proximity of M87 allows us to study the structure of this filament in…
The nature of the interaction between low-excitation gas filaments at ~10^4 K, seen in optical line emission, and diffuse X-ray emitting coronal gas at ~10^7 K in the centers of galaxy clusters remains a puzzle. The presence of a strong,…
X-ray observations of M87 in the Virgo cluster and NGC 4874 in Coma reveal that the gas temperature beyond about 50 kpc from these cD galaxies is comparable to the virial temperature of the cluster, 3 or 9 keV respectively, but within the…
We present a spectral analysis of cool and cooling gas in 45 cool-core clusters and groups of galaxies obtained from Reflection Grating Spectrometer (RGS) XMM-$Newton$ observations. The high-resolution spectra show FeXVII emission in many…
We report CO observations towards MS0735.6+7421 a distant cooling core galaxy, and towards M87, the nearest cooling core in the center of the Virgo cluster. Both galaxies contain radio cavities that are thought to be responsible for the…
We report the discovery of a 40 arcsec long X-ray filament in the core of the cluster of galaxies A1795. The feature coincides with an Halpha+NII filament found by Cowie et al in the early 1980s and resolved into at least 2 U-band filaments…
Using a combination of deep 574ks Chandra data, XMM-Newton high-resolution spectra, and optical Halpha+NII images, we study the nature and spatial distribution of the multiphase plasma in M87. Our results provide direct observational…
We present a study of the properties of the transition temperature (T~10^5 K) gas in the Milky Way corona, based on measurements of OVI, NV, CIV, SiIV and FeIII absorption lines seen in the far ultraviolet spectra of 58 sightlines to…
Early-type galaxies often contain a hot X-ray emitting interstellar medium (3-8E6 K) with an apparent radiative cooling time much less than a Hubble time. If unopposed by a heating mechanism, the gas will radiatively cool to temperatures <=…
Based on mapping observations with ASCA, an unusual hot region with a spatial extent of 1 square degree was discovered between M87 and M49 at a center coordinate of R. A. = 12h 27m 36s and Dec. = $9^\circ18'$ (J2000). The X-ray emission…
We use a deep XMM-Newton Reflection Grating Spectrometer observation to examine the X-ray emission from the core of the Centaurus cluster of galaxies. We clearly detect Fe-XVII emission at four separate wavelengths, indicating the presence…
Many massive galaxies at the centres of relaxed galaxy clusters and groups have vast reservoirs of cool (~10,000 K) and cold (~100 K) gas. In many low redshift brightest group and cluster galaxies this gas is lifted into the hot ISM in…
We combine observations of spiral galaxies in the [CII] line at 158 micron, made with the Long Wavelength Spectrometer aboard ISO, with previous data from the Kuiper Airborne Observatory to study the origin of this line, which is the main…
The discovery of EUV and soft X-ray excess emission in clusters of galaxies (the cluster soft-excess phenomenon) challenged the notion of the hot ($\sim 10^{7-8}$ K) gas as the only dominant thermal component of the intracluster medium…
The physics of the coolest phases in the hot Intra-Cluster Medium (ICM) of clusters of galaxies is yet to be fully unveiled. X-ray cavities blown by the central Active Galactic Nucleus (AGN) contain enough energy to heat the surrounding gas…
We have searched the far-UV spectra of five clusters of galaxies observed with the Hopkins Ultraviolet Telescope (HUT) for emission in the resonance lines of O VI (1032,1038 A) and C IV (1548,1551 A). We do not detect significant emission…
We present Suzaku spectra of X-ray emission in the fields just off the LMC X-3 sight line. OVII, OVIII, and NeIX emission lines are clearly detected, suggesting the presence of an optically thin thermal plasma with an average temperature of…