English
Related papers

Related papers: Determining the Absolute Astrometric Error in Chan…

200 papers

We present an extensive and well-characterized Chandra X-ray Galaxy Catalog (CGC) of 8557 galaxy candidates in the redshift range z ~ 0.04 - 0.7, optical luminosity 1010 - 1011 Lro, and X-ray luminosity (0.5-7 keV) LX = 2x1040 - 2x1043 erg…

We describe a standard star catalog constructed using multiple SDSS photometric observations (at least four per band, with a median of ten) in the $ugriz$ system. The catalog includes 1.01 million non-variable unresolved objects from the…

Astrophysics · Physics 2008-11-26 Zeljko Ivezic , J. Allyn Smith , Gajus Miknaitis , Huan Lin , Douglas Tucker

The China Space Station Telescope (CSST) will conduct a deep and wide imaging survey in the NUV-, u-, g-, r-, i-, z-, and y-bands. In this work, using theoretical data synthesized from the BOSZ spectra of Bohlin et al. (2017), along with…

Solar and Stellar Astrophysics · Physics 2025-11-04 Xue Lu , Haibo Yuan , Kai Xiao , Bowen Huang , Ruoyi Zhang , Lin Yang , Timothy C. Beers , Shuai Xu

Astrometric accuracy of complex modern VLBI arrays cannot be calculated analytically. We study the astrometric accuracy of phase-referenced VLBI observations for the VLBA, EVN and global VLBI array by simulating VLBI data for targets at…

Astrophysics · Physics 2009-11-11 N. Pradel , P. Charlot , J. -F. Lestrade

We present a modified adaptive matched filter algorithm designed to identify clusters of galaxies in wide-field imaging surveys such as the Sloan Digital Sky Survey. The cluster-finding technique is fully adaptive to imaging surveys with…

Astrophysics · Physics 2009-11-13 Feng Dong , Elena Pierpaoli , James E. Gunn , Risa H. Wechsler

Presented here are the details of the astrometric reductions from the x,y data to mean Right Ascension (RA), Declination (Dec) coordinates of the third U.S. Naval Observatory (USNO) CCD Astrograph Catalog (UCAC3). For these new reductions…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Charlie T. Finch , Norbert Zacharias , Gary L. Wycoff

We review the systematic uncertainties that have plagued attempts to obtain high precision and high accuracy from ground-based photometric measurements using CCDs. We identify two main challenges in breaking through the 1% precision…

Astrophysics · Physics 2008-11-26 Christopher W. Stubbs , John L. Tonry

We present revised positions for the 1051 galaxies belonging to the Karachentseva Catalog of Isolated Galaxies (CIG). New positions were calculated by applying SExtractor to the Digitized Sky Survey CIG fields with a spatial resolution of…

Astrophysics · Physics 2009-11-10 S. Leon , L. Verdes-Montenegro

We present and describe a catalog of galaxy photometric redshifts (photo-z's) for the Sloan Digital Sky Survey (SDSS) Data Release 6 (DR6). We use the Artificial Neural Network (ANN) technique to calculate photo-z's and the Nearest Neighbor…

Astrophysics · Physics 2008-11-26 Hiroaki Oyaizu , Marcos Lima , Carlos E. Cunha , Huan Lin , Joshua Frieman , Erin S. Sheldon

The third US Naval Observatory (USNO) CCD Astrograph Catalog, UCAC3 was released at the IAU General Assembly on 2009 August 10. It is a highly accurate, all-sky astrometric catalog of about 100 million stars in the R = 8 to 16 magnitude…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Norbert Zacharias

We present an independent validation and comprehensive re-calibration of S-PLUS Ultra-Short Survey (USS) DR1 12-band photometry using about 30,000--70,000 standard stars from the BEst STar (BEST) database. We identify spatial variation of…

An accurate calibration of the source redshift distribution $p(z)$ is a key aspect in the analysis of cosmic shear data. This, one way or another, requires the use of spectroscopic or high-quality photometric samples. However, the…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-25 Carlos García-García , David Alonso , Pedro G. Ferreira , Boryana Hadzhiyska , Andrina Nicola , Carles Sánchez , Anže Slosar

The $Chandra$ archival data is a valuable resource for various studies on different topics of X-ray astronomy. In this paper, we utilize this wealth and present a uniformly processed data set, which can be used to address a wide range of…

Solar and Stellar Astrophysics · Physics 2016-06-22 Song Wang , Jifeng Liu , Yanli Qiu , Yu Bai , Huiqin Yang , Jincheng Guo , Peng Zhang

The second USNO CCD Astrograph Catalog, UCAC2 was released in July 2003. Positions and proper motions for 48,330,571 sources (mostly stars) are available on 3 CDs, supplemented with 2MASS photometry for 99.5% of the sources. The catalog…

We present a new procedure for photometric parallax estimation. The data for 1236 stars provide calibrations between the absolute magnitude offset from the Hyades main-sequence and the UV-excess for different (B-V)o colour-index intervals,…

Astrophysics · Physics 2009-11-10 S. Karaali , Y. Karatas , S. Bilir , S. Ak , E. Hamzaoglu

Thick fully depleted CCDs, while enabling wide spectral response, also present challenges in understanding the systematic errors due to 3D charge transport. This 2014 Workshop on Precision Astronomy with Fully Depleted CCDs covered progress…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 J. A. Tyson

We assess the systematic uncertainties in stellar evolutionary calculations for low- to intermediate-mass, main-sequence stars. We compare published stellar tracks from several different evolution codes with our own tracks computed using…

Solar and Stellar Astrophysics · Physics 2016-02-17 R. J. Stancliffe , L. Fossati , J. -C. Passy , F. R. N. Schneider

We have derived a new photographic photometry and proper motions for 20000 stars with completeness to V = 18 in the direction of galactic center at the intermediate latitude (l = 3 deg,b = 47 deg; alpha(1950)=15h 18m, delta(1950) = +02deg…

Astrophysics · Physics 2007-05-23 D. K. Ojha , O. Bienayme , A. C. Robin , V. Mohan

New micro-satellite constellations enable unprecedented systematic monitoring applications thanks to their wide coverage and short revisit capabilities. However, the large volumes of images that they produce have uneven qualities, creating…

Computer Vision and Pattern Recognition · Computer Science 2019-04-22 Jérémy Anger , Carlo de Franchis , Gabriele Facciolo

The Red-Sequence Cluster Survey (RCS) is a $\sim$100 square degree, two-filter imaging survey in the $R_C$ and $z'$ filters, designed primarily to locate and characterise galaxy clusters to redshifts as high as $z=1.4$. This paper provides…

Astrophysics · Physics 2010-04-06 Michael D. Gladders , Howard K. C. Yee
‹ Prev 1 3 4 5 6 7 10 Next ›