Related papers: Determining the Absolute Astrometric Error in Chan…

We compare Stetson's photometric standards with measurements listed in a standard star catalog constructed using repeated SDSS imaging observations. The SDSS catalog includes over 700,000 candidate standard stars from the equatorial stripe…

We systematically investigate the error sources for high-precision astrometry from adaptive optics based near-infrared imaging data. We focus on the application in the crowded stellar field in the Galactic Center. We show that at the level…

Accurate weak lensing mass estimates of clusters are needed in order to calibrate mass proxies for the cosmological exploitation of galaxy cluster surveys. Such measurements require accurate knowledge of the redshift distribution of the…

We report the probable identification of the X-ray counterpart to the gamma-ray pulsar PSR J2021+4026 using imaging with the Chandra X-ray Observatory ACIS and timing analysis with the Fermi satellite. Given the statistical and systematic…

Masses of clusters of galaxies from weak gravitational lensing analyses of ever larger samples are increasingly used as the reference to which baryonic scaling relations are compared. In this paper we revisit the analysis of a sample of 50…

A cosmic ray observatory with full-sky coverage can exploit standard anisotropy analysis methods that do not work if part of the celestial sphere is never seen. In particular, the distribution of arrival directions can be fully…

Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by the European Space Agency Gaia satellite during the first 22 months of its operational phase. We…

We present the Chandra Multiwavelength Project (ChaMP) X-ray point source catalog with ~6,800 X-ray sources detected in 149 Chandra observations covering \~10 deg^2. The full ChaMP catalog sample is seven times larger than the initial…

We present a catalog of bulge, disk, and total stellar mass estimates for ~660,000 galaxies in the Legacy area of the Sloan Digital Sky Survey Data Release 7. These masses are based on a homogeneous catalog of g- and r-band photometry…

We present the "C4 Cluster Catalog", a new sample of 748 clusters of galaxies identified in the spectroscopic sample of the Second Data Release (DR2) of the Sloan Digital Sky Survey (SDSS). The C4 cluster--finding algorithm identifies…

By means of CCD photometry in three bands (Gunn g, r, i) we investigate the existence of 12 candidate clusters extracted via a model independent peak finding algorithm (\cite{memsait}) from DPOSS data. The derived color-magnitude diagrams…

We present the third installment of the Yale/San Juan Southern Proper Motion Catalog, SPM3. Absolute proper motions, positions, and photographic B,V photometry are given for roughly 10.7 million objects, primarily stars, down to a magnitude…

The COSMOS-Legacy survey is a 4.6 Ms Chandra program that has imaged 2.2 deg$^2$ of the COSMOS field with an effective exposure of $\simeq$160 ks over the central 1.5 deg$^2$ and of $\simeq$80 ks in the remaining area. The survey is the…

Accurate relative spectrophotometry is critical for many science applications. Small wavelength scale residuals in the flux calibration can significantly impact the measurements of weak emission and absorption features in the spectra. Using…

Using repeat imaging of a galaxy cluster taken over a seventeen-year baseline, we examine the impact that degraded Charge Transfer Efficiency (CTE) has on photometric measurements of extended sources using the ACS/WFC on HST. We examine how…

This paper presents the exact error analysis of point positioning equation used for airborne three-dimensional(3D) imaging sensor. With differential calculus and principles of precision analysis a mathematics formula on the point position…

Upcoming and ongoing large area weak lensing surveys will also discover large samples of galaxy clusters. Accurate and precise masses of galaxy clusters are of major importance for cosmology, for example, in establishing well calibrated…

We present identification and astrometry of all previously known or suspected variables along with the discovery of six new variables in the globular cluster M3. The number of the catalogized variables increased to 274 by including all the…

Galaxy cross-correlations with high-fidelity redshift samples hold the potential to precisely calibrate systematic photometric redshift uncertainties arising from the unavailability of complete and representative training and validation…

We have tested the application to Sloan Digital Sky Survey data of the software package MATCH, which fits color-magnitude diagrams (CMDs) to estimate stellar population parameters and distances. These tests on a set of six globular clusters…