G. S. Hennessy
A5048243223- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysics and Star Formation Studies
- Astrophysical Phenomena and Observations
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Remote Sensing in Agriculture
- CCD and CMOS Imaging Sensors
- Calibration and Measurement Techniques
- Cosmology and Gravitation Theories
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Scientific Research and Discoveries
- Astro and Planetary Science
- History and Developments in Astronomy
- Infrared Target Detection Methodologies
- Spacecraft Design and Technology
- Planetary Science and Exploration
- Photocathodes and Microchannel Plates
- Inertial Sensor and Navigation
- Oceanographic and Atmospheric Processes
- Space Exploration and Technology
United States Naval Observatory
2005-2020
Association of Universities For Research In Astronomy
2009
University of Virginia
2001
Goddard Space Flight Center
1992
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...
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...
We measure cosmological parameters using the three-dimensional power spectrum $P(k)$ from over 200 000 galaxies in Sloan Digital Sky Survey (SDSS) combination with Wilkinson Microwave Anisotropy Probe (WMAP) and other data. Our results are consistent a ``vanilla'' flat adiabatic cold dark matter model constant without tilt ${(n}_{s}=1),$ running tilt, tensor modes, or massive neutrinos. Adding SDSS information more than halves WMAP-only error bars on some parameters, tightening...
We present the large-scale correlation function measured from a spectroscopic sample of 46,748 luminous red galaxies Sloan Digital Sky Survey. The survey region covers 0.72 h-3 Gpc3 over 3816 deg2 and 0.16 < z 0.47, making it best yet for study structure. find well-detected peak in at 100 h-1 Mpc separation that is an excellent match to predicted shape location imprint recombination-epoch acoustic oscillations on low-redshift clustering matter. This detection demonstrates linear growth...
The Sloan Digital Sky Survey (SDSS) is an imaging and spectroscopic survey that will eventually cover approximately one-quarter of the celestial sphere collect spectra ≈106 galaxies, 100,000 quasars, 30,000 stars, serendipity targets. In 2001 June, SDSS released to general astronomical community its early data release, roughly 462 deg2 including almost 14 million detected objects 54,008 follow-up spectra. were collected in drift-scan mode five bandpasses (u, g, r, i, z); our 95% completeness...
We have created a variety of composite quasar spectra using homogeneous data set over 2200 from the Sloan Digital Sky Survey (SDSS). The sample spans redshift range 0.044 ≤ z 4.789 and an absolute r' magnitude -18.0 to -26.5. input cover observed wavelength 3800–9200 Å at resolution 1800. median covers rest-wavelength 800 8555 reaches peak signal-to-noise ratio 300 per 1 element in rest frame. identified 80 emission-line features spectrum. Emission-line shifts relative nominal laboratory...
We measure the large-scale real-space power spectrum P(k) using a sample of 205,443 galaxies from Sloan Digital Sky Survey, covering 2417 square degrees with mean redshift z~0.1. employ matrix-based method pseudo-Karhunen-Loeve eigenmodes, producing uncorrelated minimum-variance measurements in 22 k-bands both clustering and its anisotropy due to redshift-space distortions, narrow well-behaved window functions range 0.02 h/Mpc < k 0.3h/Mpc. pay particular attention modeling, quantifying...
We study the optical colors of 147,920 galaxies brighter than g* = 21, observed in five bands by Sloan Digital Sky Survey (SDSS) over ∼100 deg2 high Galactic latitude sky along celestial equator. The distribution g*-r* versus u*-g* color-color diagram is strongly bimodal, with an optimal color separator u*-r* 2.22. use visual morphology and spectral classification subsamples 287 500 galaxies, respectively, to show that two peaks correspond roughly early- (E, S0, Sa) late-type (Sb, Sc, Irr)...
We measure the large-scale real-space power spectrum $P(k)$ using luminous red galaxies (LRGs) in Sloan Digital Sky Survey (SDSS) and use this measurement to sharpen constraints on cosmological parameters from Wilkinson Microwave Anisotropy Probe (WMAP). employ a matrix-based estimation method Pseudo-Karhunen-Lo\`eve eigenmodes, producing uncorrelated minimum-variance measurements 20 $k$-bands of both clustering its anisotropy due redshift-space distortions, with narrow well-behaved window...
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 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...
We present the results from a survey of i-dropout objects selected ∼1550 deg2 multicolor imaging data Sloan Digital Sky Survey to search for luminous quasars at z ≳ 5.8. Objects with i*-z* > 2.2 and z* < 20.2 are selected, follow-up J-band photometry is used separate L- T-type cool dwarfs high-redshift quasars. describe discovery three new quasars, SDSSp J083643.85+005453.3 (z = 5.82), J130608.26+035626.3 5.99), J103027.10+052455.0 6.28). The quasar radio source flux 1.1 mJy 20 cm. spectra...
We present moderate-resolution Keck spectroscopy of quasars at z = 5.82, 5.99, and 6.28, discovered by the Sloan Digital Sky Survey (SDSS). find that Lyα absorption in spectra these evolves strongly with redshift. To ∼ 5.7, as expected from an extrapolation lower redshifts. However, highest-redshift object, SDSSp J103027.10+052455.0 (z 6.28), average transmitted flux is 0.0038 ± 0.0026 times continuum level over 8450 Å < λ 8710 (5.95 zabs 6.16), consistent zero flux. Thus drops a factor...
We study the luminosity and color dependence of galaxy two-point correlation function in Sloan Digital Sky Survey, starting from a sample ~200,000 galaxies over 2500 deg2. concentrate our analysis on volume-limited subsamples specified ranges, for which we measure projected wp(rp), is directly related to real-space ξ(r). The amplitude wp(rp) rises continuously with Mr ≈ -17.5 -22.5, most rapid increase occurring above characteristic L* (Mr -20.5). Over scales 0.1 h-1 Mpc < rp 10 Mpc,...
The astrometric calibration of the Sloan Digital Sky Survey is described. For point sources brighter than r ∼ 20, accuracy 45 mas rms per coordinate when reduced against USNO CCD Astrograph Catalog and 75 Tycho-2, with an additional 20–30 systematic error in both cases. errors are dominated by anomalous refraction random primary reference catalogs. relative between filter each other filters (u, g, i, z) 25–35 rms. At survey limit (r 22), limited photon statistics to approximately 100 for...
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...
In the course of its commissioning observations, Sloan Digital Sky Survey (SDSS) has produced one largest redshift samples galaxies selected from CCD images. Using 11,275 complete to r* = 17.6 over 140 deg2, we compute luminosity function in band a range -23 < M -16 (for h 1). The result is well-described by Schechter with parameters ϕ* (1.46 ± 0.12) × 10-2 h3 Mpc-3, M* -20.83 0.03, and α -1.20 0.03. implied density j ≈ (2.6 0.3) 108h L⊙ Mpc-3. We find that surface brightness selection...
We present the first measurements of clustering in Sloan Digital Sky Survey (SDSS) galaxy redshift survey. Our sample consists 29,300 galaxies with redshifts 5,700 km/s < cz 39,000 km/s, distributed several long but narrow (2.5-5 degree) segments, covering 690 square degrees. For full, flux-limited sample, redshift-space correlation length is approximately 8 Mpc/h. The two-dimensional function ξ(r_p,π) shows clear signatures both small-scale, ``fingers-of-God'' distortion caused by...
We identify new structures in the halo of Milky Way Galaxy from positions, colors and magnitudes five million stars detected Sloan Digital Sky Survey. Most these are within 1.26 degrees celestial equator. present color-magnitude diagrams (CMDs) for two previously discovered, tidally disrupted structures. The CMDs turnoff consistent with those Sagittarius dwarf galaxy, as had been predicted. In one direction, we even able to detect a clump red stars, similar that dwarf, spread across 110...
We discuss the optical and radio properties of ∼30,000 FIRST (radio, 20 cm, sensitive to 1 mJy) sources positionally associated within 15 with a Sloan Digital Sky Survey (SDSS) (optical, r* ∼ 22.2) source in 1230 deg2 sky. The matched sample represents ∼30% 108,000 0.1% 2.5 × 107 SDSS studied region. spectra are available for 4300 galaxies 1154 quasars from control 140,000 20,000 1030 Here we analyze only core sources, which dominate sample; fraction SDSS-FIRST complex morphology is...
We discuss measurements of the properties ∼13,000 asteroids detected in 500 deg2 sky Sloan Digital Sky Survey (SDSS) commissioning data. The moving objects are magnitude range 14 < r* 21.5, with a baseline ∼5 minutes, resulting typical velocity errors ∼3%. Extensive tests show that sample is at least 98% complete, contamination rate less than 3%. find size distribution resembles broken power law, independent heliocentric distance: D-2.3 for 0.4 km ≲ D 5 km, and D-4 40 km. As consequence this...
We report the discovery of two well-defined tidal tails emerging from sparse remote globular cluster Palomar 5. These stretch out symmetrically to both sides in direction constant Galactic latitude and subtend an angle 26 on sky. The have been detected commissioning data Sloan Digital Sky Survey, providing deep five-color photometry a 25-wide band along equator. stars make up substantial part (~) current total population magnitude interval 19.5 ≤ i* 22.0. This reveals that is subject heavy...