Search Publications
The Stellar Abundances and Galactic Evolution Survey: Photonic Passbands and Extinction Coefficients for the u and v Bands
Tan, Ke-Feng; Zhao, Gang; Fan, Zhou +6 more
The Stellar Abundances and Galactic Evolution Survey (SAGES) is a multi-band photometric survey focused on estimation of stellar atmospheric parameters and interstellar extinction. In this paper we have derived photonic passbands for the intermediate-band u and v filters of the SAGES photometric system. The derived photonic passbands have been com…
An insight to the cryospheric level in Mars: Case study from the Thaumasia Minor
Dasgupta, Dipayan; Kundu, Abhik; Dasgupta, Nilanjan
The presence of a subsurface Martian cryosphere has been widely acknowledged. Rampart craters and outflow channels are thought to be the prominent geomorphic signatures in support of the presence of this cryospheric layer. Valley networks, on the other hand, are thought to be the signatures of precipitation, seasonal meltwater flow due to glacial …
Extragalactic transient candidates in the second Swift-XRT point source catalogue
O'Brien, P. T.; Starling, R. L. C.; Evans, P. A. +1 more
The second Swift-XRT Point Source catalogue offers a combination of sky coverage and sensitivity and presents an invaluable opportunity for transient discovery. We search the catalogue at the positions of inactive and active galaxies, and identify transient candidates by comparison with XMM-Newton and ROSAT. We recover 167 previously known transie…
The impact of photospheric brightness field on exoplanetary transit timings and the TTV excess of HD 189733 b
Baluev, Roman V.
We consider the issue of excessive TTV noise observed for the exoplanet HD 189733 b. Trying to explain it through the host star photospheric activity, we model the stellar surface brightness as a random field, then characterize statistical properties of the resulting transit signal perturbation and compute individual corrections to transit timings…
The role of pre-existing faults and fractures in shaping polygonal impact craters and its tectonic implications in the southern Margaritifer Terra region, Mars
Bhattacharya, Satadru; Dasgupta, Dipayan; Kundu, Abhik +2 more
The presence of polygonal-shaped craters, i.e., craters with complete or incomplete polygonal rims along with circular or elliptical outlines, on the surface of celestial bodies has been known for nearly a century. However, many investigations on their distribution and formation have not been carried out, until recently. Scientists have proposed t…
Activity of Selected Solar Twins
Shlyapnikov, A. A.; Katsova, M. M.; Nizamov, B. A.
We analyze various tracers of magnetic activity for 23 solar twins which are characterized by significant scatter of lithium abundance in their atmospheres. A level of coronal and chromospheric activity has been studied from available X-ray and UV-archival data. It gives us a chance to compare coronae of solar twins of various ages with the solar …
An Effusive Lunar Dome Near Fracastorius Crater: Spectral and Morphometric Properties
Ahrens, Caitlin; Lena, Raffaello
We examine a dome within the boundary between Fracastorius crater and Mare Nectaris. The dome has a noticeable vent structure and appears to be perpendicular to wrinkle ridges in the southern Mare Nectaris basin. The spectral signature of this dome, derived from Clementine UVVIS and Chandrayaan-1 M3 reflectance data, revealed that Fracastorius has…
Photometric Analysis of Two K Spectral Type Contact Binary Systems
Aceves, H.; Michel, R.; Popov, V. +3 more
The first analysis of the light curves of contact binaries ROTSE J135349.8+305205 (CB1) and 1SWASP J150957.5‑115308 (CB2) using the Wilson-Devinney code is presented. Both binary systems are of the A-subtype with a shallow fill-out (20.8% and 15.8% respectively) and a difference in temperatures between the components of < 200 K. A mass-ratio of…
A Matched Survey for the Enigmatic Low Radio Frequency Transient ILT J225347+862146
Hallinan, Gregg; Sharma, Yashvi; Huang, Yuping +3 more
Discovered in 2011 with LOFAR, the 15 Jy low-frequency radio transient ILT J225347+862146 heralds a potentially prolific population of radio transients at <100 MHz. However, subsequent transient searches in similar parameter space yielded no detections. We test the hypothesis that these surveys at comparable sensitivity have missed the populati…
Determining the Spectral Content of MOSES Images
Kankelborg, Charles C.; Parker, Jacob D.
The Multi-Order Solar Extreme Ultraviolet Spectrograph (MOSES) sounding rocket was launched from White Sands Missile Range on 2006 February 8th, to capture images of the Sun in the He II 303.8 Å emission line. MOSES is a slitless spectrograph that forms images in multiple spectral orders simultaneously using a concave diffraction grating in an eff…