相关论文: A secondary clump of red giant stars: why and wher…

Some fine structures can nowadays be identified in the high-quality colour-magnitude diagrams (CMD) of Local Group galaxies. The clump of red giants, for instance, may present a significant colour spread, and extensions to both brighter and…

We examine the morphology of the color-magnitude diagram (CMD) for core helium-burning (red clump) stars to test the recent suggestion by Zaritsky & Lin (1997) that an extension of the red clump in the Large Magellanic Cloud (LMC) toward…

Giant clumps are a characteristic feature of observed high-redshift disk galaxies. We propose that these kpc-sized clumps have a complex substructure and are the result of many smaller clumps self-organizing themselves into clump clusters…

Colour-magnitude diagrams (CMD) of the SMC star cluster NGC419, derived from HST/ACS data, reveal a well-delineated secondary clump located below the classical compact red clump typical of intermediate-age populations. We demonstrate that…

The red clump stars in the open cluster NGC 752 present a peculiar distribution in the colour-magnitude diagran (CMD): the clump is observed to present a faint extension, slightly to the blue of the main concentration of clump stars. We…

We identify a vertical extension of the red clump stars in the color magnitude diagram (CMD) of a section of the Large Magellanic Cloud (LMC). After subtracting the principal red clump component, we find a peak in the residual stellar…

We present Washington C, T1 CCD photometry of 21 fields located in the northern part of the Large Magellanic Cloud (LMC), and spread over a region of more than 2.52 degrees approximately 6 degrees from the bar. The surveyed areas were…

The I-band brightness of clump stars has been used recently to determine the distance to the bulge, the LMC and SMC, and to M31. It was assumed to be a standard candle based on the observational fact that it is independent of (V-I)-colour…

(Abridged) The properties of stellar clumps in star forming galaxies and their evolution over the redshift range $2\lesssim z \lesssim 6$ are presented and discussed in the context of the build-up of massive galaxies at early cosmic times.…

(Abridged) We report a discovery of possible large-scale structures around the RDCS J1252.9-2927 cluster at z=1.24 based on photometric redshifts. We carried out multi-band wide-field imaging with Suprime-Cam on the Subaru Telescope and…

We present the I-band luminosity function of the differentially reddened globular cluster M10. We combine photometric analysis derived from wide-field (23' x 23') images that include the outer regions of the cluster and high-resolution…

The global star formation rate has decreased significantly since z ~ 1, for reasons that are not well understood. Red-sequence galaxies, dominating in galaxy clusters, represent the population that have had their star formation shut off,…

The color-magnitude diagram (CMD) of globular cluster NGC1651 has special structures including a broad main sequence, an extended main sequence turn-off and an extended red giant clump. The reason for such special CMDs remains unclear. In…

We perform a detailed analysis of the resolved colors and stellar populations of a complete sample of 323 star-forming galaxies at 0.5 < z < 1.5, and 326 star-forming galaxies at 1.5 < z < 2.5 in the ERS and CANDELS-Deep region of…

We present deep HST/ACS observations of the G1 clump, a distinct stellar overdensity lying at ~30 kpc along the south-western major axis of M31 close to the G1 globular cluster (Ferguson et al. 2002). Our well-populated colour-magnitude…

Massive star-forming clumps are a prominent feature of high-redshift galaxies and are thought to trace gravitational fragmentation, feedback, and bulge growth in gas-rich disks. We present a statistical analysis of clumps in $\sim$3600…

Studying giant star-forming clumps in distant galaxies is important to understand galaxy formation and evolution. At present, however, observers and theorists have not reached a consensus on whether the observed "clumps" in distant galaxies…

In the Galactic center nuclear star cluster, bright late-type stars exhibit a flat or even a decreasing surface-density profile, while fainter late-type stars maintain a cusp-like profile. Historically, the lack of red giants in the…

Evidence for a second main-sequence turn-off in a deep colour-magnitude diagram of NGC 1868 is presented. The data were obtained with HST/WFPC2 and reach down to m_{555} ~ 25. Besides the usual t ~ 0.8 Gyr turn-off found in previous…

The double red clump (RC) observed in the Milky Way bulge is widely interpreted as evidence for an X-shaped structure. We have recently suggested, however, an alternative interpretation based on the multiple population phenomenon, where the…