Results 1 to 10 of about 2,565,021 (373)

An Extreme-precision Radial-velocity Pipeline: First Radial Velocities from EXPRES [PDF]

open access: bronzeThe Astronomical Journal, 2020
Abstract 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 target radial-velocity (RV) precision of 30 cm s−1.
Ryan R. Petersburg   +15 more
semanticscholar   +6 more sources

Long-lived, long-period radial velocity variations in Aldebaran: A planetary companion and stellar activity [PDF]

open access: bronze, 2015
We investigate the nature of the long-period radial velocity variations in Alpha Tau first reported over 20 years ago. We analyzed precise stellar radial velocity measurements for Alpha Tau spanning over 30 years.
A. P. Hatzes   +16 more
core   +5 more sources

Measurement of target radial velocity

open access: greenИзвестия высших учебных заведений России: Радиоэлектроника, 2015
The multichannel and single-channel measuring instruments of target radial velocity with use multifrequency signals at presence correlated and non-correlated handicapes are synthesized.
D. I. Popov
doaj   +1 more source

Automatic Recognition Algorithm of Convergence Region Based on Relative Storm Radial Velocity Field

open access: yes应用气象学报, 2021
An algorithm for automatically identifying the mid-altitude radial convergence from the storm-relative radial velocity field is proposed. The algorithm first identifies the positive-negative velocity segments in each radial direction on the single ...
Zhu Li, Kang Lan
doaj   +1 more source

Precise Radial Velocities and Radial Velocity Standards [PDF]

open access: yesSymposium - International Astronomical Union, 1985
By imposing absorption lines of HF in stellar spectra we can measure changes in r.v. with a precision of ~10m/s from a single spectrum, provided stellar line profiles are not distorted by atmospheric motions. The precision of absolute radial velocities is currently limited to ~100m/s by knowledge of rest wavelengths.
G. A. H. Walker   +3 more
openaire   +1 more source

TOI 560: Two Transiting Planets Orbiting a K Dwarf Validated with iSHELL, PFS, and HIRES RVs

open access: yesThe Astronomical Journal, 2022
We validate the presence of a two-planet system orbiting the 0.15–1.4 Gyr K4 dwarf TOI 560 (HD 73583). The system consists of an inner moderately eccentric transiting mini-Neptune (TOI 560 b, $P={6.3980661}_{-0.0000097}^{+0.0000095}$ days, $e={0.294}_{-0.
Mohammed El Mufti   +95 more
doaj   +1 more source

Correction of Dual-PRF Velocity for Operational S-Band Doppler Weather Radar

open access: yesRemote Sensing, 2023
The Weather Radar Center (WRC) of the Korea Meteorological Administration (KMA) has been providing three-dimensional radar wind fields based on the “WInd Synthesis System using Doppler Measurements (WISSDOM)” in real time since February 2019.
So-Yeon Park   +2 more
doaj   +1 more source

Automated Recognition of Macro Downburst Using Doppler Weather Radar

open access: yesAtmosphere, 2022
In light of the macro downburst’s ground divergent flow field characteristics and high reflectivity, this paper proposes an algorithm for identifying the downburst area using a Doppler weather radar low-level radial velocity and reflectivity factor ...
Xu Wang   +4 more
doaj   +1 more source

A Study of the Radial Velocity of BX Andromedae [PDF]

open access: yesJournal of Astronomy and Space Sciences, 2004
High resolution spectroscopic observations of BX And using the BOES (Bohyunsan Optical Echelle Spectrograph) of Bohyunsan Optical Astronomical Observatory (BOAO) were performed during 26-27, Feb. 2003.
Chung-Uk Lee   +3 more
doaj   +1 more source

Hydrodynamic flow between rotating stretchable disks in an orthotropic porous medium [PDF]

open access: yesSongklanakarin Journal of Science and Technology (SJST), 2020
A mathematical model of convective steady flow over rotating disks in an orthotropic porous medium has been developed and solved the non-dimentional governing equations for flow by the shooting method that uses fourth order Runge- Kutta integration ...
K. Gowthami   +3 more
doaj   +1 more source

Home - About - Disclaimer - Privacy