Search Publications
A Catalog of RV Variable Star Candidates from LAMOST
Liu, Gaochao; Wu, Yaqian; Xiang, Maosheng +14 more
Radial velocity (RV) variable stars are important in astrophysics. The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) spectroscopic survey has provided ∼6.5 million stellar spectra in its Data Release 4 (DR4). During the survey ∼4.7 million unique sources were targeted and ∼1 million stars observed repeatedly. The probabilities…
Turbulence and Energetic Particles in Radiative Shock Waves in the Cygnus Loop. I. Shock Properties
Blair, William P.; Slavin, Jonathan D.; Raymond, John C. +3 more
We have obtained a contiguous set of long-slit spectra of a shock wave in the Cygnus Loop to investigate its structure, which is far from the morphology predicted by 1D models. Proper motions from Hubble Space Telescope images combined with the known distance to the Cygnus Loop provide an accurate shock speed. Earlier analyses of shock spectra est…
Recurring Homologous Solar Eruptions in NOAA AR 11429
Zhang, Jie; Vemareddy, Panditi; Karna, Nishu +1 more
We present the study of three homologous solar eruptions from NOAA active region (AR) 11429 over four days. This large and complex AR is divided into two relatively simple subregions: northeast (NE) and southwest (SW). Recurrent eruptions occurred from the SW subregion over different evolutionary phases, which provided a unique opportunity to isol…
Spectroscopic Constraints on the Buildup of Intracluster Light in the Coma Cluster
van Dokkum, Pieter; Bizyaev, Dmitry; Pan, Kaike +14 more
The stellar content of the intracluster light (ICL) provides unique insight into the hierarchical assembly process of galaxy clusters. We present optical spectra of three ICL regions (µg ≈ 25.3-26.2 mag arcsec-2) in the Coma cluster, located between 100 and 180 kpc from their nearest brightest cluster galaxies (BCGs): N…
The spatial evolution of young massive clusters. II. Looking for imprints of star formation in NGC 2264 with Gaia DR2
Hacar, Álvaro; Buckner, Anne S. M.; Khorrami, Zeinab +12 more
Context. Better understanding of star formation in clusters with high-mass stars requires rigorous dynamical and spatial analyses of star-forming regions.
Aims: We seek to demonstrate that "INDICATE" is a powerful spatial analysis tool which when combined with kinematic data from Gaia DR2 can be used to probe star formation history in a robus…
Very wide companion fraction from Gaia DR2: A weak or no enhancement for hot Jupiter hosts, and a strong enhancement for contact binaries
Zakamska, Nadia L.; Schlaufman, Kevin C.; Hwang, Hsiang-Chih +1 more
There is an ongoing debate on whether hot Jupiter hosts are more likely to be found in wide binaries with separations of ≳100 AU. In this paper, we search for comoving, very wide companions with separations of 103-104 AU for hot Jupiter hosts and main-sequence contact binaries in Gaia DR2, and compare the very wide companion …
Monte Carlo control loops for cosmic shear cosmology with DES Year 1 data
Smith, M.; Annis, J.; Bertin, E. +53 more
Weak lensing by large-scale structure is a powerful probe of cosmology and of the dark universe. This cosmic shear technique relies on the accurate measurement of the shapes and redshifts of background galaxies and requires precise control of systematic errors. Monte Carlo control loops (MCCL) is a forward modeling method designed to tackle this p…
Chemical Properties of the Local Galactic Disk and Halo. I. Fundamental Properties of 1544 Nearby, High Proper-motion M Dwarfs and Subdwarfs
Lépine, Sébastien; Rich, R. Michael; Shara, Michael M. +2 more
Due to their ubiquity and very long main-sequence lifetimes, M dwarfs provide an excellent tool to study the formation and chemical enrichment history of our Galaxy. However, owing to their intrinsic faintness, the acquisition of high-resolution, high signal-to-noise spectra of low-mass stars has been limited to small numbers of very nearby stars,…
Magnetospheric Studies: A Requirement for Addressing Interdisciplinary Mysteries in the Ice Giant Systems
Roussos, E.; Rymer, A.; Allen, R. C. +18 more
Uranus and Neptune are the least-explored planets in our Solar System. This paper summarizes mysteries about these incredibly intriguing planets and their environments spurred by our limited observations from Voyager 2 and Earth-based systems. Several of these observations are either inconsistent with our current understanding built from exploring…
Super-resolution of SDO/HMI Magnetograms Using Novel Deep Learning Methods
Moon, Yong-Jae; Lim, Daye; Rahman, Sumiaya +3 more
Image super-resolution is a technique of enhancing the resolution of an image where a high-resolution (HR) image is reconstructed from a low-resolution (LR) image. In this Letter, we apply two novel deep learning models (residual attention model and progressive GAN model) for enhancing Solar Dynamics Observatory (SDO)/Helioseismic and Magnetic Ima…