Abstract We determine the detection limits of search for dwarf galaxies in Pan-Andromeda Archaeological Survey (PAndAS) using algorithm developed by PAndAS team. The recovery fractions artificial are, as expected, a strong function physical size and luminosity and, to lesser extent, distance. show that these vary strongly with location surveyed area because varying levels contamination from bot...

A comprehensive study of the co-evolution globular cluster systems (GCS) in galaxies requires ability to model both large scale dynamics (0.01 - 10 kpc) regulating their orbital evolution, and small (sub-pc AU) internal each (GC). In this work we present a novel method that combine semi-analytic models GCS with fully self-consistent Monte Carlo simultaneously evolve GCSs. We use population synt...

We present a photometric survey of the stellar halo of the nearest giant spiral galaxy, Andromeda (M31), using Suprime-Cam on the Subaru Telescope. A detailed analysis of V I color-magnitude diagrams of the resolved stellar population is used to measure properties such as line-of-sight distance, surface brightness, metallicity, and age, and these are used to isolate and characterize different c...

The upside-down jellyfish Cassiopea is a globally distributed, semi-sessile, planktonically dispersed scyphomedusa. Cassiopea occurs in shallow, tropical inshore marine waters on sandy mudflats and is generally associated with mangrove-dominated habitats. Controversy over the taxonomy of upside-down jellyfishes precedes their introduction to the Hawaiian Islands during the Second World War, and...

We identify nearby disk galaxies with optical structural parameters similar to those of intermediateredshift compact blue galaxies. By comparing H I and optical emission-line widths, we show that the optical widths substantially underestimate the true kinematic widths of the local galaxies. By analogy, optical emission-line widths may underrepresent the masses of intermediate-z compact objects....

According to cosmological theory, density fluctuations of Cold Dark Matter (CDM) form the first structures in the Universe. The gravitational potential wells of these dark matter halos suck in primordial gas and provide the seeds for the formation of stars via energy dissipation and cooling, a billion years after the Big Bang. The observational Universe today is filled with these galaxies, the ...

Positron annihilation line at 511 keV is a known component of the gamma-ray diffuse emission. It believed to be produced in Galaxy, but there could possible extragalactic contribution as well. E.g., positrons can jets active galactic nuclei (AGN) and after that accumulate gradually annihilate hot gaseous halos around galaxies. In this work we test hypothesis application an individual object—the...

We present a Very Large Array (VLA) H I 21cm map and optical observations of the region around one of the nearest damped Lyman-α absorber beyond the local group, SBS 1543+593. Two previously uncataloged galaxies have been discovered and a redshift has been determined for a third. All three of these galaxies are at the redshift of SBS 1543+593 and are < ∼185 kpc from the damped Lyman-α absorber....

We have constrained the age of the globular cluster S312 in the Andromeda galaxy (M31) by comparing its multicolor photometry with theoretical stellar population synthesis models. This is both a check on the age of this globular cluster, as well a check on our methodology. Main-sequence photometry has been the most direct method for determining the age of a star cluster. S312 was observed as pa...