相关论文: On nonconvex constellations among primes II: (458,…
We present a direct N-body simulation modeling the evolution of the old (7 Gyr) open cluster NGC 188. This is the first N-body open cluster simulation whose initial binary population is directly defined by observations of a specific open…
A key yet unresolved question in modern-day astronomy is how galaxies formed and evolved under the paradigm of the $\Lambda$CDM model. A critical limiting factor lies in the lack of robust tools to describe the merger history through a…
We used ultra-deep observations obtained with the NIRCam aboard the James Webb Space Telescope to explore the stellar population of NGC 6440: a typical massive, obscured and contaminated globular cluster formed and orbiting within the…
The progenitors of present-day galaxy clusters offer crucial insight into how galaxies and large-scale structure co-evolve in the early Universe. We present JWST/NIRCam grism spectroscopy of the photometrically identified $z=7.66$…
We investigate the evolution of early-type galaxies in four clusters at z=0.4 (Abell370, Cl0303+17, Cl0939+47 and Cl1447+26) and in one at z=0.55 (Cl0016+16). The galaxies are selected according to their spectrophotometrically determined…
We use direct N-body simulations to investigate the evolution of star clusters with large size-scales with the particular goal of understanding the so-called extended clusters observed in various Local Group galaxies, including M31 and…
We investigate the origin of extragalactic continuum emission and its relation to the stellar population of a recently discovered peculiar z=3.344 Lyman alpha emitter. Based on an analysis of the broad-band colors and morphology we find…
Observations of diffuse starlight in the outskirts of galaxies are thought to be a fundamental source of constraints on the cosmological context of galaxy assembly in the $\Lambda$CDM model. Such observations are not trivial because of the…
A dozen short-period detached binaries are known to host transiting circumbinary planets. In all circumbinary systems so far, the planetary and binary orbits are aligned within a couple of degrees. However, the obliquity of the primary…
In this paper we produce infinite families of counterexamples to Jantzen's question posed in 1980 on the existence of Weyl $p$-filtrations for Weyl modules for an algebraic group and Donkin's Tilting Module Conjecture formulated in 1990.…
The growth of galaxies is a key problem in understanding the structure and evolution of the universe. Galaxies grow their stellar mass by a combination of star formation and mergers, with a relative importance that is redshift dependent.…
We perform evolutionary calculations for a binary system with initial parameters: $M_{sg,i}$= 1$M\odot$ and $M_{ns,i}$= 1.4 $M\odot$ and $P_{orb,i}(RLOF)$= 1.27 d to produce observed binary parameters for the PSR J1740--5340. Our…
Observational investigations of the abundance of massive precursors of local galaxy clusters ("proto-clusters") allow us to test the growth of density perturbations, to constrain cosmological parameters that control it, to test the theory…
We present the results of Monte Carlo simulations for the dynamical evolution of star clusters containing two stellar populations with individual masses m1 and m2 > m1, and total masses M1 and M2 < M1. We use both King and Plummer model…
Let $A(\ell,n,k)$ denote the number of $\ell$-tuples of commuting permutations of $n$ elements whose permutation action results in exactly $k$ orbits or connected components. We provide a new proof of an explicit formula for $A(\ell,n,k)$…
We present preliminary results of a long-term study aimed at answering a number of open questions on the evolution of starbursts in local galaxies. The project employes mainly HST data from the ultraviolet to the red of the stellar…
In this paper, observational constraints on the cosmic equation of state of dark energy ($p = w \rho$) have been investigated using gravitational lensing statistics. A likelihood analysis of the lens surveys has been carried out to…
Recently, G. Mason has produced a counterexample of order 128 to a conjecture in conformal field theory and tensor category theory in [Ma]. Here we easily produce an infinite family of counterexamples, the smallest of which has order 72.
We study additive properties of consecutive prime numbers and the primality of the sums they generate. For a given prime number $p_n$, we consider the sums \[ S_k(p_n) = p_n + p_{n+1} + \cdots + p_{n+k-1}, \] where $k \ge 3$ is an odd…
We study M/L evolution of early-type galaxies using dynamical modeling of resolved internal kinematics. This makes fewer assumptions than Fundamental Plane (FP) studies and provides a powerful new approach for studying galaxy evolution. We…