705 citations · 12k across the 299 of their papers we have counts for
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Limits on planetary-mass primordial black holes from the OGLE high-cadence survey of the Magellanic Clouds
Przemek Mróz, Andrzej Udalski, Michał K. Szymański +11
Observations of the Galactic bulge revealed an excess of short-timescale gravitational microlensing events that are generally attributed to a large population of free-floating or w…
Application of Stochastic Modeling to Analysis of Photometric Reverberation Mapping Data
Ying Zu, C. S. Kochanek, Szymon Kozłowski +1
We use both simulated and real quasar light curves to explore modeling photometric reverberation-mapping (RM) data as a stochastic process. We do this using modifications to our pr…
A plausible (overlooked) super-luminous supernova in the SDSS Stripe 82 data
Zuzanna Kostrzewa-Rutkowska, Szymon Kozlowski, Lukasz Wyrzykowski +4
We present the discovery of a plausible super-luminous supernova (SLSN), found in the archival data of Sloan Digital Sky Survey (SDSS) Stripe 82, called PSN 000123+000504. The supe…
The Magellanic Quasars Survey. III. Spectroscopic Confirmation of 758 AGNs Behind the Magellanic Clouds
Szymon Kozlowski, Christopher A. Onken, Christopher S. Kochanek +12
The Magellanic Quasars Survey (MQS) has now increased the number of quasars known behind the Magellanic Clouds by almost an order of magnitude. All survey fields in the Large Magel…
Further Evidence that Quasar X-Ray Emitting Regions Are Compact: X-Ray and Optical Microlensing in the Lensed Quasar Q J0158-4325
Christopher W. Morgan, Laura J. Hainline, Bin Chen +9
We present four new seasons of optical monitoring data and six epochs of X-ray photometry for the doubly-imaged lensed quasar Q J0158-4325. The high-amplitude, short-period microle…
Is Quasar Optical Variability a Damped Random Walk?
Ying Zu, C. S. Kochanek, Szymon Kozłowski +1
The damped random walk (DRW) model is increasingly used to model the variability in quasar optical light curves, but it is still uncertain whether the DRW model provides an adequat…
Discovery of Energy Dependent X-ray Microlensing in Q2237+0305
Bin Chen, Xinyu Dai, Christopher S. Kochanek +3
We present our long term Chandra X-ray monitoring data for the gravitationally lensed quasar Q2237+0305 with 20 epochs spanning 10 years. We easily detect microlensing variability…
The Magellanic Quasars Survey. II. Confirmation of 144 New Active Galactic Nuclei Behind the Southern Edge of the Large Magellanic Cloud
Szymon Kozlowski, C. S. Kochanek, A. M. Jacyszyn +9
We quadruple the number of quasars known behind the Large Magellanic Cloud (LMC) from 55 (42 in the LMC fields of the third phase of the Optical Gravitational Lensing Experiment (O…
The Magellanic Quasars Survey. I. Doubling the Number of Known AGNs Behind the Small Magellanic Cloud
Szymon Kozlowski, Christopher S. Kochanek, Andrzej Udalski
We report the spectroscopic confirmation of 29 new, 12 plausible, and 3 previously known quasars behind the central ~1.5 deg^2 region of the Small Magellanic Cloud. These were iden…
Quasar Selection Based on Photometric Variability
C. L. MacLeod, K. Brooks, Z. Ivezic +7
We develop a method for separating quasars from other variable point sources using SDSS Stripe 82 light curve data for ~10,000 variable objects. To statistically describe quasar va…
Black Hole Mass Estimates Based on CIV are Consistent with Those Based on the Balmer Lines
R. J. Assef, K. D. Denney, C. S. Kochanek +39
Using a sample of high-redshift lensed quasars from the CASTLES project with observed-frame ultraviolet or optical and near-infrared spectra, we have searched for possible biases b…
SDWFS-MT-1: A Self-Obscured Luminous Supernova at z~0.2
Szymon Kozlowski, C. S. Kochanek, D. Stern +22
We report the discovery of a six-month-long mid-infrared transient, SDWFS-MT-1 (aka SN 2007va), in the Spitzer Deep, Wide-Field Survey of the NOAO Deep Wide-Field Survey Bootes fie…
Modeling the Time Variability of SDSS Stripe 82 Quasars as a Damped Random Walk
C. L. MacLeod, Ž. Ivezić, C. S. Kochanek +10
We model the time variability of ~9,000 spectroscopically confirmed quasars in SDSS Stripe 82 as a damped random walk. Using 2.7 million photometric measurements collected over 10…
Mid-Infrared Variability from the Spitzer Deep, Wide-Field Survey
Szymon Kozlowski, Christopher S. Kochanek, Daniel Stern +30
We use the multi-epoch, mid-infrared Spitzer Deep, Wide-Field Survey to investigate the variability of 474,179 objects in 8.1 deg^2 of the NDWFS Bootes field. We perform a Differen…
Quantifying Quasar Variability As Part of a General Approach To Classifying Continuously Varying Sources
Szymon Kozlowski, Christopher S. Kochanek, A. Udalski +8
Robust fast methods to classify variable light curves in large sky surveys are becoming increasingly important. While it is relatively straightforward to identify common periodic s…