Results 1 to 10 of about 2,547,154 (400)
An Extreme-precision Radial-velocity Pipeline: First Radial Velocities from EXPRES [PDF]
The Astronomical Journal, 2020 The EXtreme-PREcision Spectrograph (EXPRES) is an environmentally stabilized, fiber-fed, R = 137,500, optical spectrograph. It was recently commissioned at the 4.3 m Lowell Discovery Telescope near Flagstaff, Arizona. The spectrograph was designed with a
R. R. Petersburg +15 more
semanticscholar +6 more sources
Geodesic Structure of the Accelerated Stephani Universe [PDF]
Symmetry, 2021 For the spherically symmetric Stephani cosmological model with an accelerated expansion, we investigate the main scenarios of the test particle and photon motion. We show that a comoving observer sees an appropriate picture.
Irina Bormotova +2 more
doaj +2 more sources
The Open Cluster NGC 7789: I. Radial Velocities for Giant Stars [PDF]
Be accpected for publication in the October 1998 issue of the PASP, 1998 A total of 597 radial-velocity observations for 112 stars in the ~1.6 Gyr old open cluster NGC 7789 have been obtained since 1979 with the radial velocity spectrometer at the Dominion Astrophysical Observatory. The mean cluster radial velocity is -54.9 +/- 0.12 km/s and the dispersion is 0.86 km/s, from 50 constant-velocity stars selected as members ...
Carraro G. +12 more
arxiv +3 more sources
Photometry as a Proxy for Stellar Activity in Radial Velocity Analyses [PDF]
Astronomical Journal, 2020 Stellar activity remains a limiting factor in measuring precise planet parameters from radial velocity spectroscopy, not least in the search for Earth-mass planets orbiting in the habitable zones of Sun-like stars.
M. Kosiarek, I. Crossfield
semanticscholar +3 more sources
Azimuthal distributions of radial momentum and velocity in relativistic heavy ion collisions [PDF]
, 2012 Azimuthal distributions of radial (transverse) momentum, mean radial momentum, and mean radial velocity of final state particles are suggested for relativistic heavy ion collisions. Using transport model AMPT with string melting, these distributions for Au + Au collisions at 200 GeV are presented and studied. It is demonstrated that the distribution of
Hwa R C +8 more
arxiv +3 more sources
Fundamental parameters of Cepheids. V. Additional photometry and radial velocity for southern Cepheids [PDF]
Astrophys.J.Suppl. 140 (2002) 465-468, 2002 I present photometric and radial velocity data for Galactic Cepheids, most of them being in the southern hemisphere. There are 1250 Geneva 7-color photometric measurements for 62 Cepheids, the average uncertainty per measurement is better than 0.01 mag.
Arellano-Ferro A. +14 more
arxiv +4 more sources
Velocity and velocity bounds in static spherically symmetric metrics [PDF]
Central Eur.J.Phys.9:926-938,2011, 2010 We find simple expressions for velocity of massless particles in dependence of the distance $r$ in Schwarzschild coordinates. For massive particles these expressions put an upper bound for the velocity. Our results apply to static spherically symmetric metrics.
Arraut, I., Batic, D., Nowakowski, M.
arxiv +7 more sources
Activity-induced radial velocity jitter in a flaring M dwarf [PDF]
, 2009 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 for spectral orders that contain very few atmospheric absorption lines and calibrated them against the telluric A ...
A. Reiners +17 more
arxiv +5 more sources
The fundamental definition of 'radial velocity' [PDF]
Astron.Astrophys.401:1185-1202,2003, 2003 Accuracy levels of metres per second require the fundamental concept of 'radial velocity' for stars and other distant objects to be examined, both as a physical velocity, and as measured by spectroscopic and astrometric techniques. Aiming at definitions that are unambiguous at accuracy levels of 1 m/s, we analyse different concepts of radial velocity ...
Lindegren, Lennart, Dravins, Dainis
arxiv +7 more sources
Radial velocity moments of dark matter haloes [PDF]
Mon.Not.Roy.Astron.Soc. 361 (2005) L1, 2005 Using cosmological N-body simulations we study the radial velocity distribution in dark matter haloes focusing on the lowest-order even moments, dispersion and kurtosis. We determine the properties of ten massive haloes in the simulation box approximating their density distribution by the NFW formula characterized by the virial mass and concentration ...
Gottloeber, Stefan +3 more
arxiv +3 more sources