Massive stars are very important for the physical and chemical evolution of the interstellar medium and the galaxy as a whole. The key to their formation is the accretion of mass onto their parent molecular cloud cores. In recent years, the rapid compression caused by supersonic collisions between molecular clouds...
Recently, observations reported that the ultra diffuse galaxy NGC1052-DF2 (DF2), believed to be a member of the NGC1052 group, is dark matter (DM) deficient. Its inferred DM mass is smaller, by a factor of a few hundred, than what is expected based on its stellar mass and empirical models for...
With the success of the Event Horizon Telescope in directly imaging a supermassive black hole, the study of black holes has entered a new era in which the properties of black holes are explored through imaging observations. In particular, the polarized images reveal the magnetic field structure near the black...
Spiral galaxies observed today (redshift z=0) have distinct internal structures: supper massive black hole (SMBH), dense stellar cluster known as bulge; a flat rotating disk; and extended dark matter halo. The cosmic averaged star formation is suggested to peak at z~2. It remains unclear when and how these structures formed...
Observations confirm that the universe is accelerating and expanding. Dark energy and modified gravity theories have been proposed but a conclusive theory remains elusive. The difference between these theoretical models is reflected in the magnitude of density fluctuations and the temporal evolution of large-scale structure. Therefore, it is possible to...
The link between the intergalactic medium (IGM) and galaxies is key to understand the evolution of baryonic matter and galaxies. In fact, several observational studies have confirmed the connection between the IGM HI and galaxies up to several tens comoving Mpc. However, understanding the variations on the IGM-galaxy connection over...
Supermassive black holes in the universe that exceed one million times the mass of the sun are ubiquitous in the universe. A small proportion of supermassive black holes shine brightly and show intense activity, using accreted matter as an energy source, but most black holes hybernate quietly in the center...
Recent three-dimensional cosmological simulations of protogalaxy formation have suggested that supermassive stars (SMSs) can form in warm gas clouds in which H2–cooling is overwhelmed by dynamical heating (Wise et al. 2019), but they stopped short of following the growth of a central protostar. Here we we examine whether accretion on...
Massive stars are very important for the physical and chemical evolution of the interstellar medium and the galaxy as a whole. The key to their formation is the accretion of mass onto their parent molecular cloud cores. In recent years, the rapid compression caused by supersonic collisions between molecular clouds...
December 2021 13 : 30 molecular clouds, Milky Way, star formation, and machine learning
Recently, observations reported that the ultra diffuse galaxy NGC1052-DF2 (DF2), believed to be a member of the NGC1052 group, is dark matter (DM) deficient. Its inferred DM mass is smaller, by a factor of a few hundred, than what is expected based on its stellar mass and empirical models for...
November 2021 12 : 30 dark matter, galaxy formation, N-body simulations, and globular clusters
With the success of the Event Horizon Telescope in directly imaging a supermassive black hole, the study of black holes has entered a new era in which the properties of black holes are explored through imaging observations. In particular, the polarized images reveal the magnetic field structure near the black...
October 2021 13 : 30 black holes, AGN jets, Sgr*, radiative transfer, and general relativity
Spiral galaxies observed today (redshift z=0) have distinct internal structures: supper massive black hole (SMBH), dense stellar cluster known as bulge; a flat rotating disk; and extended dark matter halo. The cosmic averaged star formation is suggested to peak at z~2. It remains unclear when and how these structures formed...
September 2021 13 : 30 galaxy fromation, galactic disk, ALMA, and galactic halos
Observations confirm that the universe is accelerating and expanding. Dark energy and modified gravity theories have been proposed but a conclusive theory remains elusive. The difference between these theoretical models is reflected in the magnitude of density fluctuations and the temporal evolution of large-scale structure. Therefore, it is possible to...
July 2021 13 : 30 large scale structure, 21cm line, and N-body simulations
The link between the intergalactic medium (IGM) and galaxies is key to understand the evolution of baryonic matter and galaxies. In fact, several observational studies have confirmed the connection between the IGM HI and galaxies up to several tens comoving Mpc. However, understanding the variations on the IGM-galaxy connection over...
June 2021 13 : 30 high-z galaxies, IGM, Lyman Alpha Forest, galaxy formation, and galaxy evolution
Supermassive black holes in the universe that exceed one million times the mass of the sun are ubiquitous in the universe. A small proportion of supermassive black holes shine brightly and show intense activity, using accreted matter as an energy source, but most black holes hybernate quietly in the center...
May 2021 13 : 30 hydrodynamics, dusty torus, black holes, AGN, and galaxy mergers
Recent three-dimensional cosmological simulations of protogalaxy formation have suggested that supermassive stars (SMSs) can form in warm gas clouds in which H2–cooling is overwhelmed by dynamical heating (Wise et al. 2019), but they stopped short of following the growth of a central protostar. Here we we examine whether accretion on...
April 2021 13 : 30 first stars, large scale structure, and machine learning
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