A5062868910- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Astrophysical Phenomena and Observations
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- History and Developments in Astronomy
- Astrophysics and Cosmic Phenomena
- Pulsars and Gravitational Waves Research
- Scientific Measurement and Uncertainty Evaluation
- High-pressure geophysics and materials
- CCD and CMOS Imaging Sensors
- Mechanics and Biomechanics Studies
- Space Exploration and Technology
- Seismic Waves and Analysis
- Radio Astronomy Observations and Technology
- Planetary Science and Exploration
- Relativity and Gravitational Theory
- Dynamics and Control of Mechanical Systems
- Calibration and Measurement Techniques
- Spectroscopy and Chemometric Analyses
- Geophysics and Gravity Measurements
University of Michigan–Dearborn
2015-2024
University of Michigan–Ann Arbor
2014-2021
Indiana University Bloomington
2010-2013
University of California, Los Angeles
2009-2012
Astronomy and Space
2009
Space Telescope Science Institute
2006-2008
The Open University
2004-2008
Hong Kong Metropolitan University
2004-2006
Weidlinger Associates (United States)
2006
California Institute of Technology
2006
The SuperWASP cameras are wide‐field imaging systems at the Observatorio del Roque de los Muchachos on island of La Palma in Canary Islands, and Sutherland Station South African Astronomical Observatory. Each instrument has a field view some 482 deg2 with an angular scale 13 7 pixel−1, is capable delivering photometry accuracy better than 1% for objects having V∼7.0–11.5. Lower quality data brighter V∼15.0 stored project archive. systems, while designed to monitor fields high cadence,...
In order to contain the COVID-19 pandemic, several countries enforced extended social distancing measures for weeks, effectively pausing majority of economic activities. an effort resume activity safely, Digital Contact Tracing applications and protocols have been introduced with success. However, DCT is a reactive method, as it aims break existing chains disease transmission in population. Therefore not suitable proactively preventing spread disease; approach that relevant certain use...
HAL is a multi-disciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not.The documents may come from teaching institutions in France abroad, public private centers.L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de scientifiques niveau recherche, publiés ou non, émanant des établissements d'enseignement recherche français étrangers, laboratoires publics privés.
The WASP (Wide Angle Search for Planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other South Africa, continually monitor night sky, building up light curves of millions unique objects. These are used to search characteristics exoplanetary transits. This first public data release (DR1) archive makes available all curve from 2004 2008 both Northern Southern hemispheres. A web interface...
We have detected low-amplitude radial-velocity variations in two stars, USNO-B1.0 1219-0005465 (GSC 02265-00107 = WASP-1) and 0964-0543604 00522-01199 WASP-2). Both stars were identified as being likely host of transiting exoplanets the 2004 SuperWASP wide-field transit survey. Using newly-commissioned spectrograph SOPHIE at Observatoire de Haute-Provence, we found that both objects exhibit reflex orbital with amplitudes characteristic planetary-mass companions in-phase photometric orbits....
We report the discovery of WASP-3b, third transiting exoplanet to be discovered by WASP and SOPHIE collaboration. WASP-3b transits its host star USNO-B1.0 1256−0285133 every 1.846 834 ± 0.000 002 d. Our high-precision radial velocity measurements present a variation with amplitude characteristic planetary-mass companion in phase light curve. Adaptive optics imaging shows no evidence for nearby stellar companions, line-bisector analysis excludes faint, unresolved binarity activity as cause...
We present significantly improved proper motion measurements of the Milky Way's central stellar cluster. These improvements are made possible by refining our astrometric reference frame with a new geometric optical distortion model for W. M. Keck II 10 m telescope's Adaptive Optics camera (NIRC2) in its narrow field mode. For first time, this is constructed from on-sky measurements, and available to public. When applied widely dithered images, it produces residuals separations stars that...
We present a fast and efficient hybrid algorithm for selecting exoplanetary candidates from wide-field transit surveys. Our method is based on the widely-used SysRem Box Least-Squares (BLS) algorithms. Patterns of systematic error that are common to all stars frame mapped eliminated using algorithm. The remaining errors caused by spatially localised flat-fielding other quantified boxcar-smoothing method. show dimensions search-parameter space can be reduced greatly carrying out an initial...
We present stellar proper motions in the Galactic bulge from Sagittarius Window Eclipsing Extrasolar Search (SWEEPS) project using ACS WFC on HST. Proper are extracted for more than 180,000 objects, with >81,000 measured to accuracy better 0.3 mas yr−1 both coordinates. report several results based these measurements: (1) Kinematic separation of disk allows a sample >15,000 objects be ≥6 σ detections motion, <0.2% contamination disk. This includes first detection candidate blue straggler...
We report the first detections of Blue Straggler Stars (BSS) in bulge Milky Way galaxy. Proper motions from extensive space-based observations along a single sight-line allow us to separate sufficiently clean and well-characterized sample that we are able detect small population objects region color-magnitude diagram commonly occupied young blue strgglers. However, variability measurements these clearly establish fraction them stragglers. Out 42 found this diagram, estimate at least 18...
The Large Synoptic Survey Telescope is designed to provide an unprecedented optical imaging dataset that will support investigations of our Solar System, Galaxy and Universe, across half the sky over ten years repeated observation. However, exactly how LSST observations be taken (the observing strategy or "cadence") not yet finalized. In this dynamically-evolving community white paper, we explore detailed performance anticipated science expected depend on small changes strategy. Using...
As a young massive cluster in the Central Molecular Zone, Arches is valuable probe of stellar Initial Mass Function (IMF) extreme Galactic Center environment. We use multi-epoch Hubble Space Telescope observations to obtain high-precision proper motion and photometric measurements cluster, calculating membership probabilities for stars down 1.8 M$_{\odot}$ between radii 0.25 pc -- 3.0 pc. achieve sample with just ~8% field contamination, significant improvement over photometrically-selected...
Vera C. Rubin Observatory is a ground-based astronomical facility under construction, joint project of the National Science Foundation and U.S. Department Energy, designed to conduct multi-purpose 10-year optical survey southern hemisphere sky: Legacy Survey Space Time. Significant flexibility in strategy remains within constraints imposed by core science goals probing dark energy matter, cataloging Solar System, exploring transient sky, mapping Milky Way. The survey's massive data...
We present optical lightcurves of 428 periodic variable stars coincident with ROSAT X-ray sources, detected using the first run SuperWASP photometric survey. Only 68 these were previously recognised as variables. A further 30 objects are known pre-main sequence stars, for which we detect a modulation period time. Amongst newly identified variables, many appear to be close eclipsing binaries, their emission is presumably result RS CVn type behaviour. Others probably BY Dra and other rapid...
We report the first detection of intrinsic velocity dispersion Arches cluster - a young (~2 Myr), massive (~10,000 Solar Mass) starburst located near Galactic center. This was accomplished using proper motion measurements within central region cluster, obtained with laser guide star adaptive optics system at Keck Observatory over 3 year time baseline (2006-2009). uniform dataset results in that are improved by factor ~5 previous from heterogeneous instruments, yielding internal estimates...
We present new results from BRAVA, a large-scale radial velocity survey of the Galactic bulge, using M giant stars selected Two Micron All Sky Survey catalog as targets for Cerro Tololo Inter-American Observatory 4 m Hydra multi-object spectrograph. The purpose this is to construct generation self-consistent bar models that conform these observations. report dynamics fields at edge bulge latitudes b = −8° and compare −4°. find rotation curve V(r) same That is, boxy rotates cylindrically, do...
We present the results of a photometric survey rotation rates in Coma Berenices (Melotte 111) open cluster, using data obtained as part SuperWASP exoplanetary transit-search programme. The goal was to measure precise periods for main-sequence F, G and K dwarfs this intermediate-age (∼600 Myr) determine extent which magnetic braking has caused stellar spin converge. find tight, almost linear relationship between period J−K colour with an rms scatter only 2 per cent. relation is similar that...
Photometric transit surveys promise to complement the currently known sample of extra-solar planets (ESPs) by providing additional information on and especially their radii. Here, we present ESP candidates from one such survey called, Wide Angle Search for Planets (WASP) obtained with SuperWASP wide-field imaging system. Observations were taken North located in La Palma during 2004 April October observing season. The data cover fields between 23 03 h RA at declinations above +12. This...
We report the discovery of WASP-10b, a new transiting extrasolar planet (ESP) discovered by WASP Consortium and confirmed using NOT FIES SOPHIE radial velocity data. A 3.09 day period, 29 mmag transit depth, 2.36 hour duration are derived for WASP-10b high precision photometric observations. Simultaneous fitting to data Markov-chain Monte Carlo procedure leads radius 1.28R_J, mass 2.96M_J eccentricity ~0.06. is one more massive ESPs, we compare its characteristics current sample ESP, where...
We have derived the Galactic bulge initial mass function (IMF) of Sagittarius Window Eclipsing Extrasolar Planet Search field in range 0.15 1.0, using deep photometry collected with Advanced Camera for Surveys on Hubble Space Telescope. Observations at several epochs, spread over 9 years, allowed us to separate disk and stars down very faint magnitudes, 26 mag, a proper-motion accuracy better than 0.5 mas yr−1 (20 km s−1). This determine IMF pure component uncontaminated by this...
Recent observations have shown that a growing number of the most massive Galactic globular clusters contain multiple populations stars with different [Fe/H] and neutron-capture element abundances. NGC 6273 has only recently been recognized as member this "iron-complex" cluster class, we provide here chemical kinematic analysis > 300 red giant branch (RGB) asymptotic (AGB) using high resolution spectra obtained Magellan-M2FS VLT-FLAMES instruments. Multiple lines evidence indicate possesses...
We present photometric metallicity measurements for a sample of 2.6 million bulge red clump stars extracted from the Blanco DECam Bulge Survey (BDBS). Similar to previous studies, we find that exhibits strong vertical gradient, and at least two peaks in distribution functions appear b < -5. can discern metal-poor ([Fe/H] ~ -0.3) metal-rich +0.2) abundance each show clear systematic trends with latitude, may be best understood by changes bulge's star formation/enrichment processes. Both...
Long-term X-ray monitoring data from the Rossi X-Ray Timing Explorer (RXTE) All-Sky Monitor (ASM) and Compton Gamma Ray Observatory (CGRO) Burst And Transient Source Experiment (BATSE) reveal that third (superorbital) period in SMC X-1 is not constant, but varies between 40 60 d. A dynamic power spectrum analysis indicates has been present continuously throughout five years of ASM observations. This changed smoothly to 45 d then returned its former value, on a time-scale approximately 1600...
We present a model of the stellar populations in fields observed by one SuperWASP-N cameras 2004 observing season. use Besancon Galactic to define range types and metallicities present, populate these objects with transiting extra-solar planets using metallicity relation Fischer & Valenti (2005). investigate ability SuperWASP detect presence realistic levels correlated systematic noise (`red noise'). find that number transit signal-to-noise ratio 10 or more increases linearly nights...