Related papers: NGC 6822 as a probe of dwarf galactic evolution

We isolate a sample of 43 upper RGB stars in the extreme outer halo Galactic globular cluster NGC 2419 from two Keck/DEIMOS slitmasks. The probability that there is more than one contaminating halo field star in this sample is extremely…

Dwarf galaxies found in isolation in the Local Group (LG) are unlikely to have interacted with the large LG spirals, and therefore environmental effects should not be the main drivers of their evolution. We aim to provide insight into the…

We observed Hubble V, the brightest HII region complex in the dwarf irregular galaxy NGC 6822, at near-infrared (1.8--2.4 um) wavelengths using the Cooled Grating Spectrometer 4 (CGS4) at the United Kingdom Infra-Red Telescope (UKIRT). The…

This work establishes the most complete sample of red supergiants (RSGs) in twelve low-mass galaxies (WLM, IC 10, NGC 147, NGC 185, IC 1613, Leo A, Sextans B, Sextans A, NGC 6822, Pegasus Dwarf, SMC and LMC) of the Local Group, which forms…

We present Giant Metrewave Radio Telescope (GMRT) HI 21-cm line data for the smallest known eXtremely Metal Deficient (XMD) blue compact galaxy (BCG) HS0822+3542. From HST imaging it has been suggested that HS0822+3542 actually consists of…

High-accuracy absolute proper motions, radial velocities, and distances have now been measured for a number of dwarf-galaxy companions of the Milky Way, making it possible to study their 3D dynamics. Galactic orbits for 11 such galaxies…

We present HST WFPC2 and ground-based images of the low surface brightness dwarf Irr/Sph galaxy KKR~25 in Draco. Its colour-magnitude diagram shows red giant branch stars with the tip at I = 22.32 mag, and the presence of some blue stars.…

Context: The Asymptotic Giant Branch (AGB) phase is characterised by substantial mass loss that is accompanied by the formation of dust. In extreme cases this will make the star no longer visible in the optical. For a better understanding…

We report the discovery of Scl-MM-Dw2, a new dwarf galaxy at a projected separation of $\sim$50 kpc from NGC 253, as part of the PISCeS (Panoramic Imaging Survey of Centaurus and Sculptor) project. We measure a tip of the red giant branch…

In this Letter, we report the discovery of a new dwarf satellite to the Milky Way, located at ($\alpha_{2000}, \delta_{2000}$) $=$ (158.72,51.92) in the constellation of Ursa Major. This object was detected as an overdensity of red,…

We present HST WFPC2 and STIS imaging of the low metallicity galaxy NGC 6822, performed as part of a study of the young stellar populations in the galaxies of the Local Group. Eleven WFPC2 pointings, with some overlap, cover two regions,…

We recently inferred that the galaxy NGC1052-DF2 has little or no dark matter and a rich system of unusual globular clusters. We assumed that the galaxy is a satellite of the luminous elliptical galaxy NGC1052 at ~20 Mpc, on the basis of…

We describe a new method for robustly testing theoretical predictions of red giant evolution near the tip of the giant branch. When theoretical cumulative luminosity functions are shifted to align the tip in I-band and normalized at a…

We report the first results from our program to examine the metallicity distribution of the Milky Way nuclear star cluster connected to SgrA*, with the goal of inferring the star formation and enrichment history of this system, as well as…

(Abridged): We present U, B, V, R, I, H-alpha and NUV photometry of 14 galaxies in the very local Universe (within 10 Mpc that are dwarf irregular galaxies (dIrr), are at low redshift (51<v<610 km/s), and appear as a six degree long linear…

As part of a radial velocity survey of low Galactic latitude structures that we undertook with the 2dF spectrograph on the AAT, we present the radial velocities of more than 1500 Red Giant Branch and Red Clump stars towards the centre of…

NGC 2915 is a nearby blue compact dwarf with the HI properties of a late-type spiral. Its large, rotating HI disk (extending out to R ~ 22 B-band scale lengths) and apparent lack of stars in the outer HI disk make it a useful candidate for…

Aims. The extraplanar stellar populations of highly-inclined disk galaxies IC 2233, IC 5052, NGC 4631 and NGC 5023 are analyzed with the goal to quantify their vertical extent and structure. Methods. Based on the single-star photometry, we…

We performed a high-sensitivity search for galaxy-scale magnetic fields by radio polarimetry at 10.45GHz and 4.85GHz with the Effelsberg 100m radio telescope, accompanied by Halpha imaging, for the two Local Group irregular galaxies IC10…

Measuring the properties of the cold neutral medium (CNM) in low-metallicity galaxies provides insight into heating and cooling mechanisms in early Universe-like environments. We report detections of two localized atomic neutral hydrogen…