Search Publications
Probing the Galactic Halo with RR Lyrae Stars. I. The Catalog
Huang, Y.; Chen, B. -Q.; Wang, C. +9 more
We present a catalog of 5290 RR Lyrae stars (RRLs) with metallicities estimated from spectra of the LAMOST Experiment for Galactic Understanding and Exploration (LEGUE) and the Sloan Extension for Galactic Understanding and Exploration (SEGUE) surveys. Nearly 70% of them (3642 objects) also have systemic radial velocities measured. Given the pulsa…
Search for Nearby Earth Analogs. II. Detection of Five New Planets, Eight Planet Candidates, and Confirmation of Three Planets around Nine Nearby M Dwarfs
Butler, R. Paul; Crane, Jeffrey D.; Thompson, Ian B. +9 more
Zechmeister et al. surveyed 38 nearby M dwarfs from 2000 to 2007 March with VLT2 and the Ultraviolet and Visual Echelle Spectrograph (UVES) spectrometer. These data have recently been reanalyzed, yielding a significant improvement in the Doppler velocity precision. Spurred by this, we have combined the UVES data with velocity sets from High Accura…
An Extended Theoretical Scenario for Classical Cepheids. I. Modeling Galactic Cepheids in the Gaia Photometric System
Cignoni, Michele; Marconi, Marcella; Molinaro, Roberto +3 more
We present a new extended and detailed set of models for classical Cepheid pulsators at solar chemical composition (Z = 0.02, Y = 0.28) based on a well-tested nonlinear hydrodynamical approach. In order to model the possible dependence on crucial assumptions such as the mass-luminosity relation of central helium burning intermediate-mass stars or …
The Chandra Deep Wide-field Survey: A New Chandra Legacy Survey in the Boötes Field. I. X-Ray Point Source Catalog, Number Counts, and Multiwavelength Counterparts
Miller, Eric D.; Myers, Adam D.; Aird, James +30 more
We present a new, ambitious survey performed with the Chandra X-ray Observatory of the 9.3 deg2 Boötes field of the NOAO Deep Wide-Field Survey. The wide field probes a statistically representative volume of the universe at high redshift. The Chandra Deep Wide-field Survey exploits the excellent sensitivity and angular resolution of Cha…
Trans-Neptunian Objects Found in the First Four Years of the Dark Energy Survey
Smith, M.; Abbott, T. M. C.; Brooks, D. +62 more
We present a catalog of 316 trans-Neptunian bodies (TNOs) detected from the first four seasons ("Y4" data) of the Dark Energy Survey (DES). The survey covers a contiguous 5000 deg2 of the southern sky in the grizY optical/NIR filter set, with a typical TNO in this part of the sky being targeted by 25-30 Y4 exposures. This paper focuses …
HST/COS Observations of Quasar Outflows in the 500-1050 Å Rest Frame. I. The Most Energetic Outflows in the Universe and Other Discoveries
Xu, Xinfeng; Kriss, Gerard A.; Arav, Nahum +2 more
The Hubble Space Telescope/Cosmic Origins Spectrograph (COS) has opened a new discovery space for studying quasar absorption outflows and their contribution to active galactic nucleus (AGN) feedback. Specifically, COS provides high-quality far-ultraviolet (FUV) spectra covering the diagnostic-rich 500-1050 Å rest frame (hereafter, EUV500) of mediu…
Radial Velocity Photon Limits for the Dwarf Stars of Spectral Classes F-M
Reiners, Ansgar; Zechmeister, Mathias
The determination of extrasolar planet masses with the radial velocity (RV) technique requires spectroscopic Doppler information from the planet's host star, which varies with stellar brightness and temperature. We analyze the Doppler information in spectra from dwarfs of spectral types F-M utilizing empirical information from HARPS and CARMENES d…
Observations of the 2019 April 4 Solar Energetic Particle Event at the Parker Solar Probe
Krimigis, S. M.; Mitchell, D. G.; McComas, D. J. +33 more
A solar energetic particle event was detected by the Integrated Science Investigation of the Sun (IS⊙IS) instrument suite on Parker Solar Probe (PSP) on 2019 April 4 when the spacecraft was inside of 0.17 au and less than 1 day before its second perihelion, providing an opportunity to study solar particle acceleration and transport unprecedentedly…
Classifying Single Stars and Spectroscopic Binaries Using Optical Stellar Templates
Roulston, Benjamin R.; Green, Paul J.; Kesseli, Aurora Y.
Stellar spectral classification is a fundamental tool of modern astronomy, providing insight into physical characteristics such as effective temperature, surface gravity, and metallicity. Accurate and fast spectral typing is an integral need for large all-sky spectroscopic surveys like the Sloan Digital Sky Survey (SDSS) and the Large Sky Area Mul…
Microlensing Optical Depth and Event Rate in the OGLE-IV Galactic Plane Fields
Udalski, Andrzej; Mróz, Przemek; Szymański, Michał K. +10 more
Searches for gravitational microlensing events are traditionally concentrated on the central regions of the Galactic bulge but many microlensing events are expected to occur in the Galactic plane, far from the Galactic Center. Owing to the difficulty in conducting high-cadence observations of the Galactic plane over its vast area, which are necess…