Search Publications
Science Commissioning of NIHTS: The Near-infrared High Throughput Spectrograph on the Lowell Discovery Telescope
Cushing, Michael C.; Gustafsson, Annika; Moskovitz, Nicholas +3 more
The Near-Infrared High Throughput Spectrograph (NIHTS) is in operation on the 4.3 m Lowell Discovery Telescope (LDT) in Happy Jack, AZ. NIHTS is a low-resolution spectrograph (R ∼ 200) that operates from 0.86 to 2.45 microns. NIHTS is fed by a custom dichroic mirror which reflects near-infrared wavelengths to the spectrograph and transmits the vis…
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…
Orbital Solutions of the New Low-mass Eclipsing Binary TIC 157376469 with Spotted Activities
Zhang, Xiaobin; Zong, Weikai; Fu, Jian-Ning +4 more
We carried out a photometric and spectroscopic analysis for the eclipsing binary TIC 157376469 using the TESS and LAMOST data. A new linear ephemeris is given. By fitting the light curves and radial velocity curves with the Wilson-Devinney code, it apperas that the binary is composed of two K-type main-sequence stars. The orbit of the binary is sl…
Modeling of CO Rovibrational Line Emission of HD 141569
Najita, Joan R.; Brittain, Sean D.; Carr, John S. +1 more
HD 141569 is a Herbig Ae/Be star that straddles the boundary between the transition disks and debris disks. It is a low dust mass disk that reveals numerous structural elements (e.g., gaps and rings) that may point to young planets. It also exhibits a reservoir of CO gas observed at both millimeter and IR wavelengths. Previous observations reporte…
Low-redshift Type Ia Supernova from the LSQ/LCO Collaboration
Howell, D. A.; McCully, C.; Baltay, C. +16 more
This paper is the data release of a new sample of 140 type Ia supernovae (SNe Ia) from the LaSilla-QUEST/Las Cumbres Observatory (LCO) collaboration. The discovery of the supernovae came from the LaSilla-QUEST variability survey, the ASASSN survey, as well as smaller low redshift supernova surveys. All of the supernovae in this sample were spectro…
Evaluation of Stellar Parameters and Calibrating the Surface Gravity log g for LAMOST-II Median Resolution Survey
Luo, A. -Li; Li, Yin-Bi; Zhang, Shuo +8 more
The LAMOST II survey began in the fall of 2018, and LAMOST formally released the obtained medium-resolution spectra (MRS) as well as catalogs of stellar parameters and radial velocities (RV) derived from the MRS in the seventh LAMOST data release (DR7). Compared with the RVs and parameters from high-resolution SDSS14/APOGEE spectra, nearly no RV d…
Bayes-based Orbital Elements Estimation in Triple Hierarchical Stellar Systems
Mendez, Rene A.; Orchard, Marcos E.; Silva, Jorge F. +1 more
Under certain rather prevalent conditions (driven by dynamical orbital evolution), a hierarchical triple stellar system can be well approximated, from the standpoint of orbital parameter estimation, as two binary star systems combined. Even under this simplifying approximation, the inference of orbital elements is a challenging technical problem b…