Related papers: A Deep HST Study of the Globular Cluster NGC 6397:…

Using Hubble Space Telescope (HST) observations of the globular cluster NGC6397, we constrain the cluster's binary fraction. The observations consist of two fields: the primary science field, a single ACS pointing centered approximately 5'…

The developments summarized with the name ``weak gravitational lensing'' have led to exciting possibilities to study the (statistical properties of the) dark matter distribution in the Universe. Concentrating on those aspects which require…

Stellar sources are identified in the Hubble Deep Field, and accurate colours and magnitudes are presented. The predictions of a Galactic starcounts model are compared with the faint stellar counts in this field. The model reproduces the…

The sensitivity available to near-infrared surveys has recently allowed us to probe the galaxy population at $z\approx 7$ and beyond. The existing {\em Hubble} Wide Field Camera 3 (WFC3) and the Visible and Infrared Survey Telescope for…

We present optical morphologies obtained from deep HST and ground-based images for galaxies selected from the first sub-millimeter survey of the distant Universe. Our sample comprises galaxies detected in deep 850-micron continuum maps of…

Cosmological constraints from galaxy clusters rely on accurate measurements of the mass and internal structure of clusters. An important source of systematic uncertainty in cluster mass and structure measurements is the secure selection of…

Over its 13 years of operation (1990 -- 2002), the Faint Object Camera (FOC) on board the Hubble Space Telescope (HST) observed 26 individual active galactic nuclei (AGNs) in ultraviolet (UV) imaging polarimetry. However, not all of the…

In hierarchical galaxy formation models, galaxies evolve through mergers and accretions. Tidally-disrupted debris from these processes can remain as diffuse, faint structures, which can provide useful insight into the assembly history of…

We have undertaken a long-term project, Planets in Stellar Clusters Extensive Search (PISCES), to search for transiting planets in open clusters. As our first target we have chosen NGC 6791 -- a very old, populous, metal rich cluster. In…

We present 8 bright globular clusters and/or objects of less familiar nature which we found in the course of scrutinizing the globular cluster system of NGC 1399. These objects are morphologically striking, either by their sizes or by other…

We present the 2012 Hubble Ultra Deep Field campaign (UDF12), a large 128-orbit Cycle 19 \HST\ program aimed at extending previous WFC3/IR observations of the UDF by quadrupling the exposure time in the F105W filter, imaging in an…

We analyse high-resolution archival UVES data of turnoff and subgiant stars in the nearby globular cluster NGC 6397 ([Fe/H] = -2). Balmer-profile analyses are performed to derive reddening-free effective temperatures. Due to the limited S/N…

We identify proper motion objects in the Hubble Ultra Deep Field (UDF) using the optical data from the original UDF program in 2004 and the near-infrared data from the 128-orbit UDF 2012 campaign. There are 12 sources brighter than I=27 mag…

Using Magellan/IMACS images covering a 1.2 x 1.2 sq. degree FOV with seeing of 0.4"-0.6", we have applied convolution techniques to analyse the light distribution of 364 confirmed globular cluster in the field of NGC 5128 and to obtain…

In a spectroscopic survey of the Fornax cluster to Bj=17.5 using the FLAIR spectrograph on the UK Schmidt Telescope we have discovered seven new compact dwarf cluster members. These were previously thought to be giant background spirals.…

We present a catalog of photometry and photometric redshifts of 335 faint objects in the HDF-S NICMOS field. The analysis is based on (1) infrared images obtained with the Hubble Space Telescope (HST) using the Near Infrared Camera and…

The Grism Lens-Amplified Survey from Space (GLASS) is a Hubble Space Telescope (HST) Large Program, which will obtain 140 orbits of grism spectroscopy of the core and infall regions of 10 galaxy clusters, selected to be among the very best…

Many stars -- if they could be imaged with enough angular resolution -- would exhibit features expected from theory but not possible to extract from spectra. We may group these by increasing complexity as follows. First, smooth variations…

We present time-series VI photometry of the metal-rich ([Fe/H] = -0.53) globular cluster NGC 6441. Our color-magnitude diagram shows that the extended blue horizontal branch seen in Hubble Space Telescope data exists in the outermost…

We present an improved data-reduction technique to obtain high-precision proper motions (PMs) of globular clusters using Hubble Space Telescope data. The new reduction is superior to the one presented in the first paper of this series for…