相关论文: On a Generalized Mass-Velocity Relation for Disk G…
We present a measurement of average histograms of line-of-sight velocities over pairs of galaxies and galaxy clusters. Since the histogram can be measured at different galaxy-cluster separations, this observable is commonly referred to as…
We present central velocity dispersions, masses, mass to light ratios ($M/L$s), and rotation strengths for 25 Galactic globular clusters. We derive radial velocities of 1951 stars in 12 globular clusters from single order spectra taken with…
Up to now, the rotational velocities of galaxies are not clearly understood and the experimental Tully Fisher rule, linking the total galactic mass to the fourth power of the velocity, through an acceleration coefficient of about 10-10 m/s2…
Observations of galaxy clusters show radio emission extended over almost the system scale, necessitating mechanisms for particle acceleration. Previous models for acceleration such as diffusive shock acceleration and that due to turbulence…
General relativity (GR) is the most successful theory of gravity, with great observational support on local scales. However, to keep GR valid over cosmic scales, some phenomena (such as flat galaxy rotation curves and the cosmic expansion…
The peculiar velocity function of clusters of galaxies is determined using an accurate sample of cluster velocities based on Tully-Fisher distances of Sc galaxies (Giovanelli et al 1995b). In contrast with previous results based on samples…
We present a new empirical relation between galaxy dark matter halo mass (${\rm M_{halo}}$) and the velocity along the flat portion of the rotation curve (${\rm V_{flat}}$), derived from 120 late-type galaxies from the SPARC database. The…
Scaling relations for globular clusters (GC) differ from scaling relations for pressure supported (elliptical) galaxies. We show that two-body relaxation is the dominant mechanism in shaping the bivariate dependence of density on mass and…
The sample of dwarf galaxies with measured central black hole masses $M$ and velocity dispersions $\sigma$ has recently doubled, and gives a close fit to the extrapolation of the $M \propto \sigma$ relation for more massive galaxies. We…
In $\Lambda$CDM cosmology, to first order, galaxies form out of the cooling of baryons within the virial radius of their dark matter halo. The fractions of mass and angular momentum retained in the baryonic and stellar components of disc…
It is proposed that the baryonic Tully-Fisher relation (bTFR) and JWST 'Impossible galaxies' at cosmic dawn are unified in weak gravity by the trace $J$ of the Schouten tensor below the Sitter scale of acceleration $a_{dS}=cH$, where $c$ is…
We derive the stellar-to-halo mass relation (SHMR), namely $f_\star\propto M_\star/M_{\rm h}$ versus $M_\star$ and $M_{\rm h}$, for early-type galaxies from their near-IR luminosities (for $M_\star$) and the position-velocity distributions…
We apply the modified acceleration law obtained from Einstein gravity coupled to a massive skew symmetric field, F_{\mu\nu\lambda}, to the problem of explaining X-ray galaxy cluster masses without exotic dark matter. Utilizing X-ray…
This work present high-precision measurements of the specific baryon angular momentum jb, contained in stars, atomic gas, and molecular gas, out to ~10 scale radii, in 16 nearby spiral galaxies of the THINGS sample. The accuracy of these…
We present galaxy circular velocity functions (GCVFs) for 34 low redshift (z < 0.15) clusters identified in the Sloan Digital Sky Survey (SDSS), for fifteen clusters drawn from dark matter simulations of hierarchical structure growth in a…
We introduce a generalized scaling law, M_tot = 10^K A^a B^b, to look for the minimum scatter in reconstructing the total mass of hydrodynamically simulated X-ray galaxy clusters, given gas mass M_gas, luminosity L and temperature T. We…
This chapter presents Modified Newtonian Dynamics (MOND), the proposal that, below a certain acceleration scale $a_0$, dynamics departs from the Newtonian expectation. In that context, the determining factor for the emergence of apparent…
Observations show that galaxies follow a mass-metallicity relation over a wide range of masses. One currently favoured explanation is that less massive galaxies are less able to retain the gas and stellar ejecta and thus may lose the…
The connection between a galaxy's total globular cluster system (GCS) mass and its halo mass has been studied for decades and it has been found that galaxies at nearly all observed masses adhere to a linear scaling relation between these…
We used ionized gas and stellar kinematics for 667 spatially resolved galaxies publicly available from the Calar Alto Legacy Integral Field Area survey (CALIFA) 3rd Data Release with the aim of studying kinematic scaling relations as the…