Related papers: The Andromeda Optical and Infrared Disk Survey
Halo star clusters serve as vital tracers for the formation and evolution of the Andromeda galaxy. In this work, we present physical parameters for 29 M31 halo star clusters, derived from a combination of spectroscopic and photometric data.…
We map the distribution and properties of the Milky Way's interstellar medium as traced by diffuse interstellar bands (DIBs) detected in near-infrared stellar spectra from the SDSS-III/APOGEE survey. Focusing exclusively on the strongest…
Cosmic rays, along with stellar radiation and magnetic fields, are known to make up a significant fraction of the energy density of galaxies such as the Milky Way. When cosmic rays interact in the interstellar medium, they produce gamma-ray…
Observing nearby galaxies with submillimeter telescopes on the ground has two major challenges. First, the brightness is significantly reduced at long submillimeter wavelengths compared to the brightness at the peak of the dust emission.…
We present spectroscopic chemical abundances of red giant branch (RGB) stars in Andromeda (M31), using medium resolution ($R\sim6000$) spectra obtained via the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH)…
M31 has experienced a recent tumultuous merger history as evidenced from the many substructures that are still present in its inner halo, particularly the G1-Clump, NE- and W- shelves, and the Giant Stream (GS). We present planetary nebulae…
The subsequent coalescence of low--mass halos over cosmic time is thought to be the major formation channel of massive spiral galaxies like the Milky Way and the Andromeda Galaxy (M31). The gaseous halo of a massive galaxy is considered to…
Recent observations of our neighbouring galaxy M31 have revealed that its disk was shaped by widespread events. The evidence for this includes the high dispersion ($V/\sigma$ $\le$ 3) of stars older than 2 Gyr, and a global star formation…
We present the results of a ground-based, high spatial resolution infrared 18 micron imaging study of nearby luminous infrared galaxies (LIRGs), using the Subaru 8.2-m and Gemini South 8.1-m telescopes. The diffraction-limited images…
We present new horizontal branch (HB) distance measurements to 17 of the faintest known M31 satellites ($-6 \lesssim M_{V} \lesssim -13$) based on deep Hubble Space Telescope (HST) imaging. The color-magnitude diagrams extend $\sim$1-2…
We compare spherically-averaged radial number counts of bright (> 10^5 Lsun) dwarf satellite galaxies within 400 kpc of the Milky Way (MW) and M31 and find that the MW satellites are much more centrally concentrated. Remarkably, the two…
We discuss the first results from ongoing studies of the resolved stellar populations in the outskirts of our nearest large neighbour, M31. Deep HST/WFPC2 archival observations are used to construct colour-magnitude-diagrams which reach…
A new survey of star clusters in the South-West field of the M31 disk based on the high resolution Subaru Suprime-Cam observations is presented. The UBVRI aperture CCD photometry catalog of 285 objects (V < 20.5; 169 of them identified for…
A key processing step in ground-based astronomy involves combining multiple noisy and blurry exposures to produce an image of the night sky with an improved signal-to-noise ratio. Typically, this is achieved via image coaddition, and can be…
The M33 galaxy is a nearby, relatively metal-poor, late-type spiral. Its proximity and almost face-on inclination means that it projects over a large area on the sky, making it an ideal candidate for wide-field CCD mosaic imaging.…
We present the discovery of two new dwarf galaxies, Andromeda XXI and Andromeda XXII, located in the surroundings of the Andromeda and Triangulum galaxies (M31 and M33). These discoveries stem from the first year data of the Pan-Andromeda…
For the past five seasons, the Angstrom Project, an international microlensing collaboration, has been making observations of the central bulge of M31, the Andromeda galaxy, searching for microlensing events. This thesis describes the work…
We present an analysis of the proper motion of the Andromeda galaxy (M31), based on the Early Third Data Release of the Gaia mission. We use the Gaia photometry to select young blue main sequence stars, and apply several quality cuts to…
Using hard (E>10 keV) X-ray observations with NuSTAR, we are able to differentiate between accretion states, and thus compact object types, of neutron stars and black holes in X-ray binaries (XRBs) in M31, our nearest Milky Way-type…
We present the results of UBVRI broad-band aperture CCD photometry of 51 compact star clusters located in the South-West part of the M31 disk. The mean rms errors of all measured star cluster colors are less than 0.02 mag. In color vs.…