Related papers: Red supergiants around the obscured open cluster S…
The near-infrared behavior of the red giant branch (RGB hereafter) as a function of abundance is examined with an unprecedented large sample of 27 Galactic globular clusters with Two Micron All Sky Survey photometry. We propose a new…
The Perseus OB1 association hosts one of the most populous groupings of blue and red supergiants (Sgs) in the Galaxy. We discuss whether the massive O-type and blue/red Sg stars located in the Per OB1 region are members of the same…
The Red MSX Source (RMS) survey has identified a large sample of massive young stellar objects (MYSOs) and ultra compact (UC) HII regions from a sample of ~2000 MSX and 2MASS colour selected sources. Using a recent catalogue of molecular…
Sub-milllimetre galaxies (SMGs) are some of the most luminous star-forming galaxies in the Universe, however their properties remain hard to determine due to the difficulty of identifying their optical\slash near-infrared counterparts. One…
The first JWST data on the massive colliding cluster El Gordo confirm 23 known families of multiply lensed images and identify 8 new members of these families. Based on these families, which have been confirmed spectroscopically by MUSE, we…
The compact association Cygnus OB2 is known to contain a large population of massive stars, but its total mass is currently a matter of debate. While recent surveys have uncovered large numbers of OB stars in the area around Cyg OB2,…
Candidate clusters of galaxies drawn from the sample identified from the moderately deep I-band data of the ESO Imaging Survey (EIS), have been used for follow-up optical/infrared imaging and spectroscopic observations. The observations…
We present the serendipitous discovery of a young stellar cluster in the Galactic disk at l=12deg. Using Keck/NIRSPEC, we obtained high- and low-resolution spectroscopy of several stars in the cluster, and we identified one red supergiant…
We have used ESO telescopes at La Silla and the Hubble Space Telescope (HST) in order to obtain accurate B,V,I CCD photometry for the stars located within 200" (~= 2 half-mass radii, r_h = 1.71') from the center of the cluster NGC 6101.…
We have selected red MSX sources (RMS) that have the colours of massive young stellar objects (MYSOs). Our aim is to generate a large, systematically selected sample to address questions such as their luminosity function, lifetimes,…
We report the discovery of an X-ray luminous galaxy cluster at z=1.26. RXJ0848.9+4452 was selected as an X-ray cluster candidate in the ROSAT Deep Cluster Survey, on the basis of its spatial extent. Deep optical and near-IR imaging have…
We obtained deep Gemini GMOS-S $g,r$ photometry of the ultra-faint dwarf galaxy candidate Cetus II with the aim of providing stronger constraints on its size, luminosity and stellar population. Cetus II is an important object in the…
We have analysed a sample of 25 extremely red H-[4.5]>4 galaxies, selected using 4.5 micron data from the Spitzer SEDS survey and deep H-band data from the Hubble Space Telescope (HST) CANDELS survey, over ~180 square arcmin of the UKIDSS…
This paper is part of a project to search the inner Milky Way for hidden massive clusters and to address the question of whether our Galaxy still forms clusters similar to the progenitors of the present-day globular clusters. We report high…
We investigate the redshift 1.98 galaxy cluster XLSSC 122 using the Hubble Space Telescope (HST) from the core of the cluster out to 3 Mpc, a scale equivalent to 10 times the R500 = 295 kpc radius. We present an expanded photometric and…
Galaxy clusters are crucial to understanding role of the environment in galaxy evolution. However, due to their rarity, only a limited number of clusters have been identified at $z\gtrsim2$. In this paper, we report a discovery of seven…
The estimated total number of Milky Way globulars is 160+-20. The question of whether there are any more undiscovered globular clusters in the Milky Way is particularly relevant with advances in near and mid-IR instrumentation. This…
The environments of a complete subsample of 6 of the most powerful radio-loud AGN at redshifts z~1.6 are investigated, using deep RJK imaging to depths of R~26, J~22.4 and K~20.6. An excess of galaxy counts in the K-band is seen across…
We present the results of near-infrared spectroscopic observations of the $K$-band selected candidate galaxies in the protocluster at $z=3.09$ in the SSA22 field. We observed 67 candidates with $K_{\rm AB}<24$ and confirmed redshifts of the…
From 2MASS infra-red photometry we find two red clump (RC) populations co-existing in the same fields toward the Galactic bulge at latitudes |b|>5.5 deg., ranging over ~13 degrees in longitude and 20 degrees in latitude. We can only…