相关论文: X-ray discovery of a dwarf-galaxy galaxy collision
NGC 1232 is a face-on spiral galaxy and a great laboratory for the study of star-formation due to its proximity. We obtained high spatial resolution H{\alpha} images of this galaxy, with adaptive optics, using the SAM instrument at the SOAR…
NGC 1232 is a face-on spiral galaxy that serves as an excellent laboratory for the study of star formation due to its proximity. Recent studies have revealed interesting features about this galaxy: X-ray observations suggest that it…
Numerical simulations predict that some poor groups of galaxies have merged by the present epoch into giant ellipticals (cf. Barnes 1989). To identify the possible remnants of such mergers, we have compiled a sample of nearby, isolated…
We report the detection of a pair of dwarf galaxies at $z\!=\!0.30$ which may be in the early stages of an interaction. Both galaxies have stellar masses of $<10^{9}M_\odot$, and display a projected separation of $\sim\!29$kpc and a…
(abridged) We present an analysis of Chandra X-ray observations of a sample of eight dwarf starburst galaxies (I Zw 18, VII Zw 403, NGC 1569, NGC 3077, NGC 4214, NGC 4449, NGC 5253, and He 2-10). Extended, diffuse X-ray emission is detected…
The emission-line dwarf galaxy NGC 3413 is known to host a bright X-ray source near its optical center. The 0.3-10 keV luminosity of this source is estimated to be approximately 10$^{39}$ erg$s^{-1}$ potentially qualifying it as an…
The superb spatial resolution of Chandra is utilized to study the X-ray morphology of the dwarf starburst galaxy NGC1800 embedded in a small group of galaxies. Diffuse galactic emission is detected, extending several kpc above the galactic…
Recent studies of M31, the Galactic centre, and galaxy clusters have made tentative detections of an X-ray line at ~3.5 keV that could be produced by decaying dark matter. We use high resolution simulations of the Aquarius project to…
Group galaxies very often show distinct signs of interaction with both companion galaxies and the intragroup medium. X-ray observations are particularly helpful because they provide information on the temperatures and the densities of the…
We present results from Chandra and XMM-Newton X-ray observations of NGC 4214, a nearby dwarf starburst galaxy containing several young regions of very active star-formation. Starburst regions are known to be associated with diffuse X-ray…
Cool stars are known to produce flares probably as a result of magnetic reconnection in their outer atmospheres. We present simultaneous XMM-Newton optical V band and X-ray observations of the M8 dwarf LP412-31. During the observation a…
We have detected diffuse soft X-ray emission (0.4-1 keV) from the disk of the spiral galaxy NGC 2403 with Chandra. This diffuse emission (with a total luminosity of 2.1 x 10^38 erg/s and a gas temperature of 2-8 x 10^6 K) is well separated…
We studied the apparent galaxy pair NGC 1232 / NGC 1232A with Chandra, looking for evidence of interactions and collisions. We report that there is no cloud of diffuse emission in NGC 1232, contrary to previous claims in the literature.…
We present the discovery of a luminous X-ray AGN in the dwarf galaxy merger RGG 66. The black hole is predicted to have a mass of $M_{\rm BH} \sim 10^{5.4} M_\odot$ and to be radiating close to its Eddington limit ($L_{\rm bol}/L_{\rm Edd}…
We report on the first deeper X-ray broad-band observation of the hot spot galaxy NGC 2903 obtained with XMM-Newton. X-ray imaging and spectra of the spiral barred galaxy were obtained from XMM-Newton archival data to study its X-ray…
We use observations of gas-rich dwarf galaxies to derive constraints on dark matter scattering with ordinary matter. We require that heating/cooling due to DM interacting with gas in the Leo T dwarf galaxy not exceed the ultra-low radiative…
We examine X-ray emission produced from hot gas during collisions and mergers of disk galaxies. To study this process, we employ simulations that incorporate cosmologically motivated disk-galaxy models and include the effects of radiative…
We present a comprehensive study of the total X-ray emission from the colliding galaxy pair NGC2207/IC2163, based on Chandra, Spitzer, and GALEX data. We detect 28 ultra-luminous X-ray sources (ULXs), 7 of which were not detected previously…
We present newly discovered dwarf galaxy candidates in deep and wide-field images of NGC 1291 obtained with the Korea Microlensing Telescope Network. We identify 15 dwarf galaxy candidates by visual inspection. Using imaging simulations, we…
Deep Chandra exposures reveal the presence of diffuse X-ray emission with a luminosity of 1.3x10^{39} ergs s^{-1} from the spiral galaxy NGC 3184. This appears to be truly diffuse thermal emission distinct from the low-luminosity LMXB…