First author: Dennis Zaritsky
We present a photometric halo mass estimation technique for local galaxies that enables us to establish the stellar mass-halo mass (SMHM) relation down to stellar masses of 10$^5$ M$\odot$. We find no detectable differences among the SMHM relations of four local galaxy clusters or between the cluster and field relations and we find agreement with extrapolations of previous SMHM relations derived using abundance matching approaches. We fit a power law to our empirical SMHM relation and find that for adopted NFW dark matter profiles and for M$* < 10^9$ M$\odot$, the halo mass is M$h = 10^{10.
First author: O. Petruk
The detected polarized radio emission from remnant of SN1987A opens the possibility to unveil the structure of the pre-supernova magnetic field in the circumstellar medium. Properties derived from direct measurements would be of importance for understanding the progenitor stars and their magnetic fields. As the first step to this goal, we adopted the hydrodynamic data from an elaborated three-dimensional (3-D) numerical model of SN1987A. We have developed an approximate method for reconstruction' of 3-D magnetic field structure inside supernova remnant on the hydrodynamic background’.
Eduardo Vitral
We seek to differentiate dynamical and morphological attributes between globular clusters (GCs) that were formed inside their own dark matter (DM) mini-halo, and those who were not. We employ high resolution full N-body simulations on GPU of GCs with and without a DM mini-halo, orbiting a Fornax-like dwarf galaxy. For GCs with DM, we observe that this dark extra mass triggers a tidal radius growth that allows the mini-halo to act as a protective shield against tidal stripping, being itself stripped beforehand the stars.
First author: Joshua L. Steffen
We present a comparative study of active galactic nuclei (AGN) between galaxy pairs and isolated galaxies with the final data release of the MaNGA integral field spectroscopic survey. We build a sample of 391 kinematic galaxy pairs within the footprint of the survey and select AGN using the survey’s spectra. We use the comoving volume densities of the AGN samples to quantify the effects that tidal interactions have on the triggering of nuclear accretion.
Shubham Raghuvanshi
It has been argued that the low-mass primordial stars ($m_{\rm Pop III}\,\leq 0.8\,M_\odot$) are likely to enter the main sequence and hence possibly be found in the present-day Galaxy. However, due to limitations in existing numerical capabilities, current three-dimensional (3D) <span class="search-hit mathjax">simulations</span> of disk fragmentation are capable of following only a few thousands of years of evolution after the formation of the first protostar. In this work we use a modified version of {\sc Gadget}-2 smoothed particle hydrodynamics(SPH) code to present the results of non-linear collapse of the gas clouds associated with various degrees of initial solid body rotation (parameterized by $β$) using a piecewise polytropic equation of state.
First author: V. V. Bobylev
In recent years, radio interferometric observations have achieved high accuracy in determining the absolute values of trigonometric parallaxes and proper motions of maser radiation sources and radio stars. The error in determining the trigonometric parallaxes of these objects averages about 10 microarcseconds, which allows us to confidently study the geometric and kinematic properties of the distribution of stars located at great distances from the Sun, up to the center of the Galaxy.
First author: Ji-Yu Song
Gravitational waves (GWs) from compact binary coalescences encode the absolute luminosity distances of GW sources. Once the redshifts of GW sources are known, one can use the distance-redshift relation to constrain cosmological parameters. One way to obtain the redshifts is to localize GW sources by GW observations and then use galaxy catalogs to determine redshifts from a statistical analysis of redshift information of the potential host galaxies, and such GW data are commonly referred to as dark sirens.
First author: Camilla Pacifici
The study of galaxy evolution hinges on our ability to interpret multi-wavelength galaxy observations in terms of their physical properties. To do this, we rely on spectral energy distribution (SED) models which allow us to infer physical parameters from spectrophotometric data. In recent years, thanks to the wide and deep multi-waveband galaxy surveys, the volume of high quality data have significantly increased. Alongside the increased data, algorithms performing SED fitting have improved, including better modeling prescriptions, newer templates, and more extensive sampling in wavelength space.
First author: Kyungwon Chun
We investigate the formation channels of the intracluster light (ICL) and the brightest cluster galaxy (BCG) in clusters at $z=0$. For this, we perform multi-resolution cosmological N-body simulations using the “Galaxy Replacement Technique” (GRT). We study the formation channels of the ICL and BCG as a function of distance from the cluster center and the dynamical state of the clusters at $z=0$. To do this, we trace back the stars of the ICL and BCG, and identify the stellar components in which they existed when they first fell into the clusters.
