Search Publications
The Classification of Galaxy Morphology in the H Band of the COSMOS-DASH Field: A Combination-based Machine-learning Clustering Model
Fang, Guanwen; Lin, Zesen; Kong, Xu +6 more
By applying our previously developed two-step scheme for galaxy morphology classification, we present a catalog of galaxy morphology for H-band-selected massive galaxies in the COSMOS-DASH field, which includes 17,292 galaxies with stellar mass M ⋆ > 1010 M ⊙ at 0.5 < z < 2.5. The classification scheme is …
Search for X-Ray Quasiperiodicity of Six AGNs Using the Gaussian Process Method
Zhang, Haoyang; Yang, Shenbang; Dai, Benzhong
The quasiperiodic oscillations (QPOs) found in active galactic nuclei (AGNs) are a very interesting observational phenomenon implying an unknown physical mechanism around supermassive black holes. Several AGNs have been found to have QPO phenomena in the X-ray energy band. Long-duration X-ray observations were collected and reduced for six AGNs wi…
Molecules in the peculiar age-defying source IRAS 19312+1950
Zhang, Yong; Zhang, Jiang-Shui; Nakashima, Jun-ichi +5 more
Context. IRAS 19312+1950 is an isolated infrared source that exhibits a characteristic quasi-point-symmetric morphology in the near-and mid-infrared images and is also very bright in molecular radio lines. Because of its unique observational characteristics, various observational studies have been conducted and several hypotheses have been propose…
Supermassive black hole wake or bulgeless edge-on galaxy?
Trujillo, Ignacio; Montes, Mireia; Sánchez Almeida, Jorge
A recent paper reported the serendipitous discovery of a thin linear object interpreted as the trail of star-forming regions left behind by a runaway supermassive black hole (SMBH) kicked out from the center of a galaxy. Despite the undeniable interest in the idea, the actual physical interpretation is not devoid of difficulty. The wake of a SMBH …
The IGRINS YSO Survey. III. Stellar Parameters of Pre-main-sequence Stars in Ophiuchus and Upper Scorpius
Johns-Krull, Christopher M.; Lee, Jae-Joon; Prato, L. +9 more
We used the Immersion GRating Infrared Spectrometer (IGRINS) to determine fundamental parameters for 61 K- and M-type young stellar objects (YSOs) located in the Ophiuchus and Upper Scorpius star-forming regions. We employed synthetic spectra and a Markov chain Monte Carlo approach to fit specific K-band spectral regions and determine the photosph…
Calibrating X-Ray Binary Luminosity Functions via Optical Reconnaissance. II. The High-mass XLF and Globular Cluster Population of X-Ray Binaries in the Low Star-forming Spiral M81
Chandar, Rupali; Mok, Angus; Gallo, Elena +2 more
We characterize the optical counterparts to the compact X-ray source population within the nearby spiral galaxy M81 using multiband Hubble Space Telescope (HST) imaging data. By comparing the optical luminosities and colors measured for candidate donor stars and host clusters to stellar and cluster evolutionary models, respectively, we estimate th…
CAPOS: the bulge Cluster APOgee Survey IV elemental abundances of the bulge globular cluster NGC 6558
Monachesi, Antonela; Beers, Timothy C.; Minniti, Dante +12 more
This study presents the results concerning six red giant stars members of the globular cluster NGC 6558. Our analysis utilized high-resolution near-infrared spectra obtained through the CAPOS initiative (the APOgee Survey of Clusters in the Galactic Bulge), which focuses on surveying clusters within the Galactic Bulge, as a component of the Apache…
Astrometric calibration and source characterisation of the latest generation neuromorphic event-based cameras for space imaging
Ralph, Nicholas Owen; Marcireau, Alexandre; Afshar, Saeed +3 more
As an emerging approach to space situational awareness and space imaging, the practical use of an event-based camera (EBC) in space imaging for precise source analysis is still in its infancy. The nature of event-based space imaging and data collection needs to be further explored to develop more effective event-based space imaging systems and adv…
The Spitzer Coverage of HSC-Deep with IRAC for Z studies (SHIRAZ). I. IRAC Mosaics
Ono, Yoshiaki; Ouchi, Masami; Sawicki, Marcin +18 more
We present new Spitzer Infrared Array Camera (IRAC) 3.6 and 4.5 µm mosaics of three fields, E-COSMOS, DEEP2-F3, and ELAIS-N1. Our mosaics include both new IRAC observations as well as reprocessed archival data in these fields. These fields are part of the HSC-Deep grizy survey and have a wealth of additional ancillary data. The addition of t…
Dynamics of Four Triple Systems
Tokovinin, Andrei
Orbital motions in four hierarchical stellar systems discovered by speckle interferometry are studied. Their inner orbits are relatively well constrained, while the long outer orbits are less certain. The eccentric and misaligned inner orbits in the early-type hierarchies ϵ Cha (B9V, central star of the 5 Myr old association, P = 6.4 yr, e = 0.73)…