Search Publications
Observational and Theoretical Studies of 27 δ Scuti Stars with Investigation of the Period-Luminosity Relation
Davoudi, Fatemeh; Poro, Atila; Paki, Ehsan +11 more
The multi-color CCD photometric study of 27 δ Scuti stars is presented. By using approximately three years of photometric observations, we obtained the times of maxima and magnitude changes during the observation time interval for each star. The ephemerides of our δ Scuti stars were calculated based on the Markov Chain Monte Carlo (MCMC) method us…
The Breakthrough Listen Search for Intelligent Life: MeerKAT Target Selection
de Pater, Imke; DeBoer, David; Gajjar, Vishal +18 more
New radio telescope arrays offer unique opportunities for large-scale commensal SETI surveys. Ethernet-based architectures are allowing multiple users to access telescope data simultaneously by means of multicast Ethernet subscriptions. Breakthrough Listen will take advantage of this by conducting a commensal SETI survey on the MeerKAT radio teles…
The Weizmann Fast Astronomical Survey Telescope (W-FAST): System Overview
Gal-Yam, Avishay; Ofek, Eran O.; Yaron, Ofer +8 more
A relatively unexplored phase space of transients and stellar variability is that of second and sub-second timescales. We describe a new optical observatory operating in the Negev desert in Israel, with a 55 cm aperture, a field of view of 2°6 × 2°6 (≈7 deg2) equipped with a high frame rate, low read noise, CMOS camera. The system can o…
Probing the Astrometric Properties of Gaia EDR3 Quasars at the Faintest Magnitudes
Liao, Shilong; Qi, Zhaoxiang; Tang, Zhenghong +3 more
Gaia early data release 3 (EDR3) provides about 1.6 million QSO-like objects. Measuring the systematic residuals of the quasars convincingly in Gaia EDR3 is paramount for further fundamental astronomy use. We aim to conduct an independent assessment of the astrometric quality of Gaia EDR3 utilizing a sizable and confirmed extragalactic sources cat…
Asteroid Observations from the Transiting Exoplanet Survey Satellite: Detection Processing Pipeline and Results from Primary Mission Data
Pál, András; Vaillancourt, John E.; Kotson, Michael C. +7 more
The Transiting Exoplanet Survey Satellite (TESS) is a NASA Explorer-class mission designed for finding exoplanets around nearby stars. TESS image data can also serve as a valuable resource for asteroid and comet detection, including near-Earth objects (NEOs). In order to exploit the TESS image data for moving object detection and potential object …
Sparse Box-fitting Least Squares
Zucker, Shay; Panahi, Aviad
We present a new implementation of the commonly used Box-fitting Least Squares (BLS) algorithm, for the detection of transiting exoplanets in photometric data. Unlike BLS, our new implementation—Sparse BLS, does not use binning of the data into phase bins, nor does it use any kind of phase grid. Thus, its detection efficiency does not depend on th…
Precise Photometric Measurements from a 1903 Photographic Plate Using a Commercial Scanner
Cerny, William; Kron, Richard G.; Martinez, Michael N. +9 more
We demonstrate the feasibility of determining magnitudes of stars on archival photographic plates using a commercially available scanner. We describe one photometric approach that could serve as a useful example for other studies. In particular, we measure and calibrate stellar magnitudes from a 1903 photographic plate from the Yerkes Observatory …
Probing the Properties of Gaia-CRF2 Quasars at the Faintest Magnitudes
Liao, Shilong; Qi, Zhaoxiang; Tang, Zhenghong +1 more
Gaia data release 2 (DR2) provides the best non-rotating optical frame aligned with the radio frame (ICRF) thanks to the inclusion of about half-million quasars in the five-parameter astrometric solution. We cross-match with Gaia DR2 the quasars from Large Quasar Astrometric Catalogue, Sloan Digital Sky Survey and LAMOST, obtaining 208,743 new sou…
CSS J213934.3-050020: A New Double-mode High-amplitude δ Scuti-type Pulsating Star
Shi, Xiang-dong; Qian, Sheng-bang; Li, Lin-jia +1 more
CSS J213934.3-050020 (hereafter J213934) was originally found as an EW-type eclipsing binary star with a period of 0.225456 days by Catalina Real-time Transient Survey. With the stellar atmospheric parameters from the LAMOST, it is found that the temperature is much higher than those of normal EW-type binaries and does not follow the period-temper…
A Comprehensive Astrometric Calibration of HST's WFPC2. I. Distortion Mapping
Anderson, Jay; Horch, Elliott P.; Kozhurina-Platais, Vera +3 more
Wide field planetary camera 2 (WFPC2) exposures are already some 20 years older than Gaia epoch observations, or future James Webb Space Telescope observations. As such, they offer an unprecedented time baseline for high-precision proper-motion studies, provided the full astrometric potential of these exposures is reached. We have started such a p…