相关论文: Detection of a diffuse extended halo-like structur…

We present linear polarization in the V band for 77 stars in the field of the globular cluster 47 Tucanae (NGC 104), and for 14 bright-star-free regions, located along an elliptical isophotal contour of the cluster, as well as UBVRI…

We present new large field-of-view ($\sim$1\deg$\times$1\deg) Ca-CN photometry of the prototypical metal-rich globular cluster 47 Tucanae (NGC 104). Our results are the following. (1) The populational number ratios of the red giant branch…

We present an extensive parameter survey to study the influence of halo mass profiles on the development of tidal tails in interacting disk galaxies. We model the galaxies using a fixed exponential disk with a central bulge and vary the…

We report the discovery of diffuse stellar substructure in the Milky Way's outer halo toward Bo\"otes, unveiled by deep imaging data of the Subaru/Hyper Suprime-Cam. This substructure is detected as an excess of faint main-sequence stars,…

We report on the detection in Sloan Digital Sky Survey data of a 45 degree tidal stream of stars, extending from Bootes to Ursa Major, which we associate with the halo globular cluster NGC 5466. Using an optimal contrast, matched filter…

Based on over 5400 BV images of 47 Tuc collected between 1998 and 2010 we obtained light curves of 65 variables, 21 of which are newly detected objects. New variables are located mostly just outside of the core in a region poorly studied by…

We use Canada-France-Hawaii Telescope Legacy Survey data for 170 deg^2, recalibrated and transformed to the Sloan Digital Sky Survey ugri photometric system, to study the distribution of near-turnoff main-sequence stars in the Galactic halo…

We analyze imaging from Data Preview 1 of the Vera C. Rubin Observatory to explore the performance of early LSST pipelines in the 47 Tucanae field. The coadd-\texttt{object} catalog demonstrates the depth and precision possible with Rubin,…

Simulations of tidal streams show that close encounters with dark matter subhalos induce density gaps and distortions in on-sky path along the streams. Accordingly, observing disrupted streams in the Galactic halo would substantiate the…

We report the discovery of tidal tails around the two outer halo globular clusters, Eridanus and Palomar 15, based on $gi$-band images obtained with DECam at the CTIO 4-m Blanco Telescope. The tidal tails are among the most remote stellar…

A recent discovery of two stellar clusters associated with the diffuse high-latitude cloud HRK 81.4-77.8 has important implications for star formation in the Galactic halo. We derive a plausible distance estimate to HRK 81.4-77.8 primarily…

Until now, the study of unresolved main sequence binary stars in globular clusters has been possible almost exclusively in their central regions with deep Hubble Space Telescope (HST) observations. We present the first detection of…

The paper investigates the properties of the dust mass loss in stars populating the giant branch of the globular cluster 47 Tuc, by combining ISOCAM and DENIS data. Raster maps of 5 fields covering areas ranging from 4 x 4 to 15 x 15…

The classical globular clusters found in all galaxy types have half-light radii of $r_{\rm h} \sim$ 2-4 pc, which have been tied to formation in the dense cores of giant molecular clouds. Some old star clusters have larger sizes, and it is…

Using results from radio and X-ray observations of millisecond pulsars in 47 Tucanae, and extensive HST U, V, I imaging of the globular cluster core, we have derived a common astrometric solution good to < 0.1". A close positional…

Stellar streams provide unique probes of galactic potentials, with the longer streams normally providing the cleaner measurements. In this paper, we show an example of a short tidal stream that is particularly sensitive to the shape of the…

Our Chandra X-ray observation of the globular cluster 47 Tuc clearly detected most of the 16 MSPs with precise radio positions, and indicates probable X-ray emission from the remainder. The MSPs are soft (BB kT 0.2-0.3 keV) and faint (Lx…

I analyse the projected density distribution of member stars over a wide area surrounding 18 Galactic globular clusters using the photometric and astrometric information provided by the second data release of the Gaia mission. A 5D mixture…

We report the results of a systematic photometric survey of the peripheral regions of a sample of fourteen globular clusters in the outer halo of the Milky Way at distances d_GC>25 kpc from the Galactic centre. The survey is aimed at…

The Bright Star in the globular cluster 47 Tucanae (NGC 104) is a post-AGB star of spectral type B8 III. The ultraviolet spectra of late-B stars exhibit a myriad of absorption features, many due to species unobservable from the ground. The…