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Variable and Transient Radio Sources in the FIRST Survey
Nithyanandan Thyagarajan, David J. Helfand, Richard L. White +1
A comprehensive search for variable and transient radio sources has been conducted using ~55,000 snapshot images of the FIRST survey. We present an analysis leading to the discover…
A Comparison of X-ray and Mid-Infrared Selection of Obscured AGN
Megan E. Eckart, Ian D. McGreer, Daniel Stern +2
We compare the relative merits of AGN selection at X-ray and mid-infrared wavelengths using data from moderately deep fields observed by both Chandra and Spitzer. The X-ray-selecte…
Radio-Selected Quasars in the Sloan Digital Sky Survey
Ian D. McGreer, David J. Helfand, Richard L. White
We have conducted a pilot survey for z>3.5 quasars by combining the FIRST radio survey with the SDSS. While SDSS already targets FIRST sources for spectroscopy as quasar candidates…
Exploring the Optical Transient Sky with the Palomar Transient Factory
Arne Rau, Shrinivas R. Kulkarni, Nicholas M. Law +21
The Palomar Transient Factory (PTF) is a wide-field experiment designed to investigate the optical transient and variable sky on time scales from minutes to years. PTF uses the CFH…
Active Galaxies in the Sloan Digital Sky Survey III: from quasars to radio galaxies?
Pietro M. Reviglio, David J. Helfand
In this third of a series of papers concerning active galaxies in the FIRST and Sloan Digital Sky Surveys, we analyze the spectroscopic and radio properties of a sample of narrow-l…
Active Galaxies in the Sloan Digital Sky Survey II: galaxy and activity evolution
Pietro M. Reviglio, David J. Helfand
In this second paper of a series of papers based on the FIRST and SDSS surveys we investigate the evolution of galaxy morphology and nuclear activity in the look-back time of the S…