Related papers: Gravitational redshifts in main-sequence and giant…

We study and quantify gravitational redshift by means of relativistic ray tracing simulations of emission lines. The emitter model is based on thin, Keplerian rotating rings in the equatorial plane of a rotating black hole. Emission lines…

In the convective envelopes of relatively cool stars, oscillations are excited by turbulent convection. In these so-called solar-like oscillators, radial oscillation modes appear at nearly equally spaced frequencies. This spacing is…

We provide an observational view of evolutionary models in the Hertzsprung--Russell diagram, on the main sequence. For that we computed evolutionary models with the code STAREVOL for 15 < M/Msun < 100. We subsequently calculated atmosphere…

New observations of 16 dwarf elliptical galaxies in the Virgo Cluster indicate that at least seven dEs have significant velocity gradients along their optical major axis, with typical rotation amplitudes of 20-30 km/s. Of the remaining nine…

The peculiar radial velocities of eight clusters of galaxies, as determined from a variety of distance indicators, are consistent with a bulk flow not greatly different in direction and magnitude from the velocity vector of the Local Group…

We investigate galactic-scale outflows in the redshift range 0.71 < z < 1.63, using 413 K-band selected galaxies observed in the spectroscopic follow-up of the UKIDSS Ultra-Deep Survey (UDSz). The galaxies have an average stellar mass of…

Context: Rotation plays a key role in the life cycles of stars with masses above 8 Msun. Hence, accurate knowledge of the rotation rates of such massive stars is critical for understanding their properties and for constraining models of…

A Fourier analysis on galaxy number counts from redshift data of both the Sloan Digital Sky Survey and the 2dF Galaxy Redshift Survey indicates that galaxies have preferred periodic redshift spacings of $\Delta z =$ 0.0102, 0.0246, and…

There is growing interest in testing alternative gravity theories using the subtle gravitational redshifts in clusters of galaxies. However, current models all neglect a transverse Doppler redshift of similar magnitude, and some models are…

For a rotating galaxy, the inner circular-velocity gradient d_{R}V(0) provides a direct estimate of the central dynamical mass density, including gas, stars, and dark matter. We consider 60 low-mass galaxies with high-quality HI and/or…

We present the results of a search for unusually rapidly rotating giant stars in a large sample of K giants (~1300 stars) that had been spectroscopically monitored as potential targets for the Space Interferometry Mission's Astrometric…

We present the results of radial velocity measurements of two samples of active stars. The first sample contains field G and K giants across the Red Giant Branch, whereas the second sample consists of nearby young stars (d < 150 pc) with…

Using simulations we demonstrate that some of the published redshift distributions of submillimetre galaxies (SMGs) at different wavelengths, which were previously reported to be statistically different, are consistent with a parent…

Since 1999, a radial velocity survey of 179 red giant stars is ongoing at Lick Observatory with a one month cadence. At present ~20-100 measurements have been collected per star with an accuracy of 5 to 8 m/s. Of the stars monitored, 145…

We investigate the effect of stellar activity and flares on short-term radial velocity measurements in the mid-M flare star CN Leo. Radial velocity variations are calculated from 181 UVES spectra obtained during three nights. We searched…

We identify a sample of 324 red and 273 blue face-on spiral galaxies selected from 115 low-redshift (0.014 < z < 0.18) galaxy clusters imaged with CFHT+MegaCam in u- and r-band, KPNO 0.9-meter 2TKA and MOSAIC 8K camera in B and Rc, and…

Red giant stars are solar-like pulsators presenting mixed-modes. Such modes consist in a coupling between pressure waves propagating in the external convective envelope and gravity waves propagating in the radiative interior. Therefore, the…

Based on published sources, we have created a kinematic database on 220 massive (>10 solar masses) young Galactic star systems located within <3 kpc of the Sun. Out of them, approximately 100 objects are spectroscopic binary and multiple…

Gravitational redshift as a relativistic effect in cosmological objects is investigated. Possible signatures of the gravitational redshift in measurements of satellite galaxies in clusters of galaxies, intracluster gas, as well as galaxies…

Stellar magnetic activity induces both distortions and Doppler-shifts in the absorption line profiles of Sun-like stars. Those effects produce apparent radial velocity (RV) signals which greatly hamper the search for potentially habitable,…