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200 papers

Gamma ray bursts (GRBs) are the most energetic eruptions known in the Universe. Instruments such as Compton-GRO/BATSE and the GRB monitor on BeppoSAX have detected more than 2700 GRBs and, although observational confirmation is still…

To date, only 18 exoplanets with radial velocity (RV) semi-amplitudes $<2$ m/s have had their masses directly constrained. The biggest obstacle to RV detection of such exoplanets is variability intrinsic to stars themselves, e.g. nuisance…

Recent observations by the James Webb Space Telescope (JWST) have revealed a previously hidden population of extremely bright and compact objects between redshifts of $z \sim 4$ and $z \sim 10$. Given their extreme red colouring in the…

Astrophysics of Galaxies · Physics 2024-09-23 Jake Feeney , Patrick Kavanagh , John A. Regan

We present 594 radial velocity measurements for 71 white dwarfs obtained during our search for binary white dwarfs and not reported elsewhere. We identify three excellent candidate binaries, which require further observations to confirm our…

Astrophysics · Physics 2009-10-31 P. F. L. Maxted , T. R. Marsh , C. K. J. Moran

The GGSS is a partially-filled, all-sky survey to identify K-giant stars with low level of RV-variability. We study histograms of the radial velocity (RV) variability obtained in the early phase of the Grid Giant Star Survey (GGSS, Bizyaev…

Astrophysics · Physics 2009-11-13 Dmitry Bizyaev , Verne V. Smith

Coherent low-frequency ($\lesssim 200$ MHz) radio emission from stars encodes the conditions of the outer corona, mass-ejection events, and space weather. Previous low-frequency searches for radio emitting stellar systems have lacked the…

The discovery of new Wolf-Rayet (WR) stars in our Galaxy via large-scale narrowband optical surveys has been severely limited by dust extinction. Recent improvements in infrared technology have made narrowband-broadband imaging surveys…

High-velocity stars are interesting targets to unveil the formation of the Milky Way. In fact they can be recently accreted from an infalling dwarf galaxies or they can be the result of a turbulent merging of galaxies. Gaia is providing the…

Published data from long-term observations of a strip of sky at declination +5 degrees carried out at 7.6 cm on the RATAN-600 radio telescope are used to estimate some statistical properties of radio sources. Limits on the sensitivity of…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-24 Yu. N. Parijskij , N. S. Soboleva , A. V. Temirova , N. N. Bursov , O. P. Zhelenkova

Interstellar radar is a potential intermediate step between passive observation of exoplanets and interstellar exploratory missions. Compared to passive observation, it has the traditional advantages of radar astronomy. It can measure…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Louis K. Scheffer

Radial velocity (RV) detection of planets is hampered by astrophysical processes on the surfaces of stars that induce a stochastic signal, or "jitter", which can drown out or even mimic planetary signals. Here, we empirically and carefully…

Earth and Planetary Astrophysics · Physics 2020-04-30 Jacob K. Luhn , Jason T. Wright , Andrew W. Howard , Howard Isaacson

Radial velocity curves for 15 bright subdwarf B binary systems have been measured using high precision radial velocity measurements from high S/N optical high-resolution spectra. In addition, two bright sdB stars are discovered to be radial…

Astrophysics · Physics 2009-11-11 H. Edelmann , U. Heber , M. Altmann , C. Karl , T. Lisker

Context. Low mass stars are currently the best targets for searches for rocky planets in the habitable zone of their host star. Over the last 13 years, precise radial velocities measured with the HARPS spectrograph have identified over a…

Earth and Planetary Astrophysics · Physics 2017-06-23 N. Astudillo-Defru , T. Forveille , X. Bonfils , D. Ségransan , F. Bouchy , X. Delfosse , C. Lovis , M. Mayor , F. Murgas , F. Pepe , N. C. Santos , S. Udry , A. Wunsche

White dwarfs are among the most common objects in the stellar halo; however, due to their low luminosity and low number density compared to the stars in the discs of the Milky Way, they are scarce in the observable volume. Hence, they are…

Astrophysics of Galaxies · Physics 2017-02-09 Marco C. Lam

We present a detailed study of radio-detected dwarf galaxies (with stellar masses less than 3 billion solar masses) to characterize extreme star formation and search for (variable) radio AGNs. Our sample comes from Reines et al. (2020)…

Astrophysics of Galaxies · Physics 2026-05-01 John-Michael Eberhard , Amy E. Reines

Low-mass stars belonging to the M spectral type are the most numerous stars in our Galaxy, amounting to about two-thirds in number, and are found at the bottom of the main sequence in the H-R diagram. %Multi-wavelength studies on…

Solar and Stellar Astrophysics · Physics 2024-01-17 Samrat Ghosh , Soumen Mondal , Santosh Joshi , Sneh Lata , Rajib Kumbhakar

We present results of the largest, most comprehensive study ever done of the stellar multiplicity of the most common stars in the Galaxy, the red dwarfs. We have conducted an all-sky, volume-limited survey for stellar companions to 1120 M…

We present an updated catalog of 46,753 radial velocity (RV) standard stars selected from the APOGEE DR17. These stars cover the Northern and Southern Hemispheres almost evenly, with 62% being red giants and 38% being main-sequence stars.…

Solar and Stellar Astrophysics · Physics 2023-07-12 Qing-Zheng Li , Yang Huang , Xiao-Bo Dong

The Subaru telescope is currently performing a strategic program (SSP) using the high-precision near-infrared (NIR) spectrometer IRD to search for exoplanets around nearby mid/late-M~dwarfs via radial velocity (RV) monitoring. As part of…

The nearby brown dwarf LP 944-20 has been monitored for radial velocity variability at optical and near-infrared wavelengths using the VLT/UVES and the Keck/NIRSPEC spectrographs, respectively. The UVES radial velocity data obtained over 14…

Astrophysics · Physics 2009-11-11 E. L. Martin , E. Guenther , M. R. Zapatero Osorio , H. Bouy , R. Wainscoat