G. Gilmore
A5015365574- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- History and Developments in Astronomy
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Scientific Research and Discoveries
- Astrophysical Phenomena and Observations
- Geophysics and Gravity Measurements
- Historical Astronomy and Related Studies
- Cosmology and Gravitation Theories
- Particle physics theoretical and experimental studies
- European and International Contract Law
- Dark Matter and Cosmic Phenomena
- American Constitutional Law and Politics
- Legal principles and applications
- Particle Detector Development and Performance
- Pulsars and Gravitational Waves Research
- High-Energy Particle Collisions Research
- Spectroscopy and Chemometric Analyses
- Atmospheric Ozone and Climate
- Conflict of Laws and Jurisdiction
University of Cambridge
2016-2025
University of Alabama
2025
Institute of Astronomy
2006-2024
Bridge University
1985-2024
FORTH Institute of Molecular Biology and Biotechnology
2024
Foundation for Research and Technology Hellas
2024
Texas A&M University
2014-2023
University of Akron
2022
Max Planck Society
2018
Diego Portales University
2017
This paper describes the Seventh Data Release of Sloan Digital Sky Survey (SDSS), marking completion original goals SDSS and end phase known as SDSS-II. It includes 11,663 deg2 imaging data, with most ∼2000 increment over previous data release lying in regions low Galactic latitude. The catalog contains five-band photometry for 357 million distinct objects. survey also repeat on a 120° long, 25 wide stripe along celestial equator Southern Cap, some covered by many 90 individual runs. We...
Building on the legacy of Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program four spectroscopic surveys three scientific themes: dark energy cosmological parameters, history structure Milky Way, population giant planets around other stars. In keeping with SDSS tradition, will provide regular public releases all its data, beginning Data Release 8 (DR8), which was made in 2011 January includes SDSS-I SDSS-II images spectra reprocessed latest pipelines calibrations produced for...
We quantify the complex interdependence of stellar binarity, mass-luminosity relation, mass function, colour-magnitude relation and Galactic disc structure, all which must be understood when analysing star-count data luminosity functions. derive a mass-Mv model for change with changes in chemical abundance age. Combination this detailed modelling astrophysical observational contributions to Malmquist scatter allows us without approximating corrections. show first time that single function...
The Sloan Digital Sky Survey (SDSS) started a new phase in August 2008, with instrumentation and surveys focused on Galactic structure chemical evolution, measurements of the baryon oscillation feature clustering galaxies quasar Ly alpha forest, radial velocity search for planets around ~8000 stars. This paper describes first data release SDSS-III (and eighth counting from beginning SDSS). includes five-band imaging roughly 5200 deg^2 Southern Cap, bringing total footprint SDSS to 14,555...
The GAIA astrometric mission has recently been approved as one of the next two `cornerstones' ESA's science programme, with a launch date target not later than mid-2012. will provide positional and radial velocity measurements accuracies needed to produce stereoscopic kinematic census about billion stars throughout our Galaxy (and into Local Group), amounting 1 per cent Galactic stellar population. GAIA's main scientific goal is clarify origin history Galaxy, from quantitative populations....
The Sloan Extension for Galactic Understanding and Exploration (SEGUE) Survey obtained ≈240,000 moderate-resolution (R ∼ 1800) spectra from 3900 Å to 9000 of fainter Milky Way stars (14.0 < g 20.3) a wide variety spectral types, both main-sequence evolved objects, with the goal studying kinematics populations our Galaxy its halo. are clustered in 212 regions spaced over three quarters sky. Radial velocity accuracies at 18, degrading 20. For signal-to-noise ratio >10 per resolution element,...
We have derived absolute magnitudes from photometric parallaxes for a complete sample of ∼ 12 500 stars brighter than I = 18 in 18.24 square degrees towards the South Galactic Pole. From these data we derive stellar luminosity function visual magnitude, bolometric magnitude and mass solar neighbourhood all above thermonuclear burning limit. The total main-sequence is 0.038 m⊙ pc−3, mass-to-light ratio 1.2 (m⊙/Lv⊙). also density laws with distance plane each magnitude. shows systematic change...
We present the first data release of Radial Velocity Experiment (RAVE), an ambitious spectroscopic survey to measure radial velocities and stellar atmosphere parameters (temperature, metallicity, surface gravity) up one million stars using Six Degree Field multiobject spectrograph on 1.2 m UK Schmidt Telescope Anglo-Australian Observatory. The RAVE program started in 2003, obtaining medium-resolution spectra (median R = 7500) Ca-triplet region (8410-8795 Å) for southern hemisphere drawn from...
We use Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) u, g, r, i, z photometry to study Milky Way halo substructure in the area around north Galactic cap. A simple color cut (g - r < 0.4) reveals tidal stream of Sagittarius dwarf spheroidal galaxy, as well a number other stellar structures field. Two branches (A and B) are clearly visible an RGB composite image created from three magnitude slices, there is also evidence for still more distant wrap behind branch. comparison these data...
We present five new satellites of the Milky Way discovered in Sloan Digital Sky Survey (SDSS) imaging data, four which were followed up with either Subaru or Isaac Newton Telescopes. They include probable dwarf galaxies—one each constellations Coma Berenices, Canes Venatici, Leo, and Hercules—together one unusually extended globular cluster, Segue 1. provide distances, absolute magnitudes, half-light radii, color-magnitude diagrams for all satellites. The morphological features are generally...
Aims. We describe the photometric content of second data release Gaia project (Gaia DR2) and its validation along with quality data. Methods. The was mainly carried out using an internal analysis photometry. External comparisons were also made, but limited by precision systematics that may be present in external catalogues used. Results. In addition to assessment, we best estimates three passbands. Various colour-colour transformations are derived enable users convert between commonly used...
This paper describes the Fifth Data Release (DR5) of Sloan Digital Sky Survey (SDSS). DR5 includes all survey quality data taken through June 2005 and represents completion SDSS-I project (whose successor, SDSS-II will continue mid-2008). It five-band photometric for 217 million objects selected over 8000 square degrees, 1,048,960 spectra galaxies, quasars, stars from 5713 degrees that imaging data. These numbers represent a roughly 20% increment those Fourth Release; previous releases are...
We apply the Jeans equation to estimate masses for eight of brightest dwarf spheroidal (dSph) galaxies. For Fornax, dSph with largest kinematic data set, we obtain a model-independent constraint on maximum circular velocity, Vmax = 20+4−3 km s−1. Although only lower limits ≳ 10 s−1 remaining dSphs, find that in all cases enclosed mass at projected half-light radius is well constrained and robust wide range halo models velocity anisotropies. derive simple analytic formula estimates M(rhalf)...
We report new constraints on the local escape speed of our Galaxy. Our analysis is based a sample high velocity stars from RAVE survey and two previously published datasets. use cosmological simulations disk galaxy formation to motivate assumptions shape distribution, allowing for significantly more precise measurement compared previous studies. find that lies within range $498\kms < \ve 608 \kms$ (90 per cent confidence), with median likelihood $544\kms$. The fact $\ve^2$ greater than...
Gaia Early Data Release 3 contains astrometry and photometry results for about 1.8 billion sources based on observations collected by the ESA satellite during first 34 months of operations. This paper focuses photometric content, describing input data, algorithms, processing, validation results. Particular attention is given to quality data a number features that users may need take into account make best use EDR3 catalogue. The treatment BP RP background has been updated include better...
Data Release 5 (DR5) of the Radial Velocity Experiment (RAVE) is fifth data release from a magnitude-limited (9< I < 12) survey stars randomly selected in southern hemisphere. The RAVE medium-resolution spectra ($R\sim7500$) covering Ca-triplet region (8410-8795\AA) span complete time frame start observations 2003 to their completion 2013. velocities 520,781 457,588 unique are presented, which 255,922 stellar have parallaxes and proper motions Tycho-Gaia astrometric solution (TGAS) Gaia DR1....
We present a synthesis of recent photometric and kinematic data for several the most dark-matter dominated galaxies. There is bimodal distribution in half-light radii, with stable star clusters always being smaller than $\sim30$pc, while galaxies are larger $\sim120$pc. extend previously known observational relationships interpret them terms more fundamental pair intrinsic properties dark matter itself: forms cored mass distributions, core scale length greater about 100pc, has maximum...
In this Letter, we announce the discovery of a new satellite Milky Way in constellation Bootes at distance 60 kpc. It was found systematic search for stellar overdensities North Galactic Cap using Sloan Digital Sky Survey Data Release 5 (SDSS DR5). The color-magnitude diagram shows well-defined turn-off, red giant branch, and extended horizontal branch. Its absolute magnitude is -5.8, which makes it one faintest galaxies known. half-light radius 220 pc. isodensity contours are elongated have...
We present the stellar atmospheric parameters (effective temperature, surface gravity, overall metallicity), radial velocities, individual abundances, and distances determined for 425,561 stars, which constitute fourth public data release of RAdial Velocity Experiment (RAVE). The are computed using a new pipeline, based on algorithms MATISSE DEGAS. spectral degeneracies Two Micron All Sky Survey photometric information now better taken into consideration, improving parameter determination...
The combination of a spatial density distribution and velocity–distance data for stellar tracer population allows the determination both gravitational force law perpendicular to galactic plane, total surface mass disc. We have obtained new photometric spectroscopic sample K dwarfs towards south pole, analysed them using function modelling technique described in accompanying Paper I (Kuijken & Gilmore). identified can also be found, by integrating near Sun through derived Kz law, adding that...
In this Letter, we announce the discovery of a new dwarf satellite Milky Way, located in constellation Canes Venatici. It was found as stellar overdensity north Galactic cap using Sloan Digital Sky Survey Data Release 5 (SDSS DR5). The satellite's color-magnitude diagram shows well-defined red giant branch well horizontal branch. As judged from tip branch, it lies at distance ~220 kpc. Based on SDSS data, estimate an absolute magnitude MV ~ -7.9, central surface brightness μ0, V 28 mag...
We made new estimates of the Galactic escape speed at various Galactocentric radii using latest data release RAdial Velocity Experiment (RAVE DR4). Compared to previous studies we have a database that is larger by factor 10, as well reliable distance for almost all stars. Our analysis based on statistical rigorously selected sample 90 high-velocity halo stars from RAVE and previously published set. calibrated extensively tested our method suite cosmological simulations formation Milky...
We confirm and extend the recent finding that central surface density r_0*rho_0 galaxy dark matter halos, where r_0 rho_0 are halo core radius density, is nearly constant independent of luminosity. Based on co-added rotation curves about 1000 spiral galaxies, mass models individual dwarf irregular galaxies late early types with high-quality and, galaxy-galaxy weak lensing signals from a sample elliptical we find log(r_0*rho_0) = 2.15 +- 0.2, in units log(Msol/pc^2). also show observed...