P. McGehee
A5081186308- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Cosmology and Gravitation Theories
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Astro and Planetary Science
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Scientific Research and Discoveries
- Calibration and Measurement Techniques
- Atmospheric Ozone and Climate
- Geophysics and Gravity Measurements
- Space Exploration and Technology
- Molecular Spectroscopy and Structure
- Radioactive Decay and Measurement Techniques
- Adaptive optics and wavefront sensing
- Particle Accelerators and Free-Electron Lasers
- Astrophysical Phenomena and Observations
- Statistical and numerical algorithms
- Particle accelerators and beam dynamics
- Solar and Space Plasma Dynamics
- Relativity and Gravitational Theory
SLAC National Accelerator Laboratory
2023-2025
College of the Canyons
2018-2021
Infrared Processing and Analysis Center
2008-2019
California Institute of Technology
2008-2019
Los Alamos National Laboratory
1992-2014
Institut für Palliative Care
2008
New Mexico State University
2003-2006
Canada–France–Hawaii Telescope
1998
Gemini Computers (United States)
1994-1995
The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed investigations of distribution luminous and nonluminous matter in universe: a photometrically astrometrically calibrated digital imaging survey π sr above about Galactic latitude 30° five broad optical bands depth g' ∼ 23 mag, spectroscopic approximately 106 brightest galaxies 105 quasars found photometric object catalog produced by survey. This paper summarizes observational parameters products SDSS serves as an...
We describe the design, construction, and performance of Sloan Digital Sky Survey Telescope located at Apache Point Observatory. The telescope is a modified two-corrector Ritchey-Chretien design which has 2.5-m, f/2.25 primary, 1.08-m secondary, Gascoigne astigmatism corrector, one pair interchangeable highly aspheric correctors near focal plane, for imaging other spectroscopy. final ratio f/5. instrumented by wide-area, multiband CCD camera fiber-fed double spectrographs. Novel features...
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...
This paper describes the Sixth Data Release of Sloan Digital Sky Survey. With this data release, imaging northern Galactic cap is now complete. The survey contains images and parameters roughly 287 million objects over 9583 deg2, including scans a large range latitudes longitudes. also includes 1.27 spectra stars, galaxies, quasars, blank sky (for subtraction) selected 7425 deg2. release much more stellar spectroscopy than was available in previous releases detailed estimates temperatures,...
The Sloan Digital Sky Survey (SDSS) has validated and made publicly available its Second Data Release. This data release consists of 3324 deg2 five-band (ugriz) imaging with photometry for over 88 million unique objects, 367,360 spectra galaxies, quasars, stars, calibrating blank sky patches selected 2627 this area, tables measured parameters from these data. reach a depth r ≈ 22.2 (95% completeness limit point sources) are photometrically astrometrically calibrated to 2% rms 100 mas per...
This paper describes the Fourth Data Release of Sloan Digital Sky Survey (SDSS), including all survey-quality data taken through 2004 June. The release includes five-band photometric for 180 million objects selected over 6670 deg2 and 673,280 spectra galaxies, quasars, stars from 4783 those imaging using standard SDSS target selection algorithms. These numbers represent a roughly 27% increment Third Release; previous releases are included in present release. also an additional 131,840...
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,...
The Sloan Digital Sky Survey has validated and made publicly available its First Data Release. This consists of 2099 square degrees five-band (u, g, r, i, z) imaging data, 186,240 spectra galaxies, quasars, stars calibrating blank sky patches selected over 1360 this area, tables measured parameters from these data. data go to a depth r ~ 22.6 are photometrically astrometrically calibrated 2% rms 100 milli-arcsec per coordinate, respectively. cover the range 3800--9200 A, with resolution...
This paper describes the Third Data Release of Sloan Digital Sky Survey (SDSS). release, containing data taken up through 2003 June, includes imaging in five bands over 5282 deg2, photometric and astrometric catalogs 141 million objects detected these data, spectra 528,640 selected 4188 deg2. The pipelines analyzing both images spectroscopy are unchanged from those used our Second Release.
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...
An extensive sample of M, L and T dwarfs identified in the Sloan Digital Sky Survey (SDSS) has been compiled. The 718 includes 677 new objects (629 M dwarfs, 48 dwarfs) together with 41 that have previously published. All some published ones optical spectra obtained either SDSS spectrographs or Apache Point Observatory 3.5m ARC telescope. Spectral types colors are available for all objects; approximately 35% also near-infrared magnitudes measured by 2MASS on Mauna Kea system. We use this to...
We present a spectroscopic analysis of nearly 8000 late-type dwarfs in the Sloan Digital Sky Survey. Using Halpha emission line as an activity indicator, we investigate fraction active stars function spectral type and find peak near M8, confirming previous results. In contrast to past findings, that not all M7-M8 are active. show this may be selection effect distance distributions samples, appear concentrated Galactic Plane. also examine strength (ratio luminosity emitted bolometric...
The Planck High Frequency Instrument (HFI) is designed to measure the temperature and polarization anisotropies of Cosmic Microwave Background galactic foregrounds in six wide bands centered at 100, 143, 217, 353, 545 857 GHz an angular resolution 10' (100 GHz), 7' (143 5' (217 higher). HFI has been operating flawlessly since launch on 14 May 2009. bolometers cooled 100 mK as planned. settings readout electronics, such bolometer bias current, that optimize HFI's noise performance orbit are...
We examine the cloud structure around Planck detections in 71 fields observed with Herschel SPIRE instrument. wish to determine general physical characteristics of and morphology clouds where cold high column density clumps are found. derive colour temperature maps fields. infrared spectral energy distributions main clumps. The categorised according their large scale morphology. With help recently released WISE satellite data, we look for signs enhanced mid-infrared scattering (coreshine),...
We describe the processing of 336 billion raw data samples from High Frequency Instrument (HFI) which we performed to produce six temperature maps first 295 days Planck-HFI survey data. These provide an accurate rendition sky emission at 100, 143, 217, 353, 545 and 857 GHz with angular resolution ranging 9.9 4.4^2. The white noise level is around 1.5 μK degree or less in 3 main CMB channels (100--217GHz). photometric accuracy better than 2% frequencies between 100 353 7% two highest...
We explored the AllWISE catalogue of Wide-field Infrared Survey Explorer (WISE) mission and identified Young Stellar Object (YSO) candidates. Reliable 2MASS WISE photometric data combined with Planck dust opacity values were used to build our set find best classification scheme. A sophisticated statistical method, support vector machine (SVM) is analyse multidimensional space remove source types as contaminants (extragalactic sources, main-sequence stars, evolved stars sources related...
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...
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 a spectroscopic sample of 747 detached close binary systems from the Sloan Digital Sky Survey (SDSS) Fourth Data Release. The majority these binaries consist white dwarf primary and low-mass secondary (typically M dwarf) companion. have determined temperature gravity for 496 primaries spectral type magnetic activity properties 661 secondaries. estimated distances each dwarf-main-sequence star use evolutionary grids to establish age system cooling times. With respect...
The last decade has shown the great potential that X-ray Free Electron Lasers (FEL) have to study High Energy Density (HED) physics. Experiments at FELs made significant breakthroughs in Shock Physics and Dynamic Diffraction, Dense Plasma Warm Matter Science, using techniques such as isochoric heating, inelastic scattering, small angle scattering diffraction. In addition, complementary these techniques, coherent properties of FEL beam can be used image HED samples with high fidelity. We...
The Taurus Molecular Cloud subtends a large solid angle on the sky, in excess of 250 deg2. search for legitimate members to date has been limited by sky coverage as well challenge distinguishing from field interlopers. Wide-field Infrared Survey Explorer recently observed entire and we take advantage opportunity young stellar object (YSO) candidate ∼260 deg2 region designed encompass previously identified members. We use near- mid-infrared colors select objects with apparent infrared...