相关论文: UV-Bright Stellar Populations and Their Evolutiona…
We report the results of a photometric search for giant stars associated with the cores of four high velocity clouds (HVCs) -- two of which are compact HVCs -- using the Las Campanas Du Pont 2.5 meter and Cerro Tololo Blanco 4 meter…
We present evidence that the globular cluster NGC 6397 contains two distinct classes of centrally-concentrated UV-bright stars. Color-magnitude diagrams constructed from U, B, V, and I data obtained with the HST/WFPC2 reveal seven UV-bright…
Split main-sequences (MSs) and extended main-sequence turn-offs (eMSTOs) have been observed in nearly all Magellanic Clouds clusters younger than 2 Gyr. More recently, Hubble Space Telescope (HST) ultraviolet photometry uncovered a puzzling…
The UV-initiative Hubble Space Telescope Treasury survey of Galactic globular clusters provides a new window into the phenomena that shape the morphological features of the horizontal branch (HB). Using this large and homogeneous catalog of…
We present BVI CCD photometry for more than 10,000 stars in the innermost region (0.3' < r <~ 4') of the globular cluster M 3. When added to the previous photographic photometry by Buonanno et al. (1994) reaching as far as r ~ 7', this…
We investigate the multiple stellar populations in one of peculiar globular clusters (GCs) M22 using new ground-based wide-field Ca by and HST/WFC3 photometry with equivalent passbands, confirming our previous result that M22 has a…
We present the broad-band UV through mid-infrared spectral energy distributions (SEDs) of a sample of 72 spectroscopically-confirmed star-forming galaxies at z=2.30+/-0.3. Located in a 72 arcmin-squared field centered on the bright…
We present a far-ultraviolet (FUV) study of the globular cluster M30 (NGC 7099). The images were obtained using the Advanced Camera for Surveys (ACS/SBC, F150LP, FUV) and the Wide Field Planetary Camera 2 (WFPC2, F300W, UV) on board the…
We use images acquired with the Hubble Space Telescope Wide Field Camera 3 and new models to probe the Horizontal Branch (HB) population of the We use images acquired with the Hubble Space Telescope Wide Field Camera 3 and new models to…
We use a combined imaging and spectroscopic survey of the nearby central cluster galaxy, M87, to assemble a sample of 34 confirmed ultra compact dwarfs (UCDs) with half-light radii of >~ 10 pc measured from Hubble Space Telescope images.…
We present high-precision multi-band photometry for the globular cluster (GC) M2. We combine the analysis of the photometric data obtained from the Hubble Space Telescope UV Legacy Survey of Galactic GCs GO-13297, with chemical abundances…
We have surveyed the blue straggler star population of the Galactic globular cluster M5 using high-resolution images of the core along with wide-field ground-based images reaching to more than 19 core radii. To gauge M5's relative…
We collected F606W- and F814W-band time-series data of the Sagittarius low-reddening window in the Galactic bulge with the Advanced Camera far Surveys mounted on the Hubble Space Telescope. We sampled the region approximately every two…
Blue hook stars are a class of subluminous extreme horizontal branch stars that were discovered in UV images of the massive globular clusters omega Cen and NGC 2808. These stars occupy a region of the HR diagram that is unexplained by…
We investigate the effect of stellar density on the ultraviolet (UV) emission from M31's globular clusters (GCs). Published far-UV (FUV) and near-UV (NUV) colours from Galaxy Evolution and Explorer (GALEX) observations are used as a probe…
We present an analysis of the ultraviolet (UV) continuum slopes ($\beta$) for a sample of $172$ galaxy candidates at $8 < z_{\mathrm{phot}} < 16$ selected from a combination of JWST NIRCam imaging and COSMOS/UltraVISTA ground-based…
The core of the galactic globular cluster M13 (NGC 6205) has been observed with WFPC2 on the Hubble Space Telescope through visual, blue and mid- and far-UV filters in a programme devoted to study the UV population in a sample of Galactic…
We present HR Diagrams for the massive star populations in M31 and M33 including several different types of emission-line stars: the confirmed Luminous Blue Variables (LBVs), candidate LBVs, B[e] supergiants and the warm hypergiants. We…
We present a photometric catalogue of star cluster candidates in Hickson compact groups (HCGs) 7, 31, 42, 59, and 92, based on observations with the Advanced Camera for Surveys and the Wide Field Camera 3 on the Hubble Space Telescope. The…
We present GALEX data for 44 Galactic globular clusters obtained during 3 GALEX observing cycles between 2004 and 2008. This is the largest homogeneous data set on the UV photometric properties of Galactic globular clusters ever collected.…