Search Publications
AKARI and IRAS: From beam corrections to SEDs
Pearson, Chris; Clements, David L.; Wang, Lingyu +6 more
There is significant scientific value to be gained from combining AKARI fluxes with data at other far-infrared (IR) wavelengths from the Infrared Astronomical Satellite (IRAS) and Herschel missions. To be able to do this we must ensure that there are no systematic differences between the data sets that need to be corrected before the fluxes are co…
A catalog of spectroscopic binary candidate stars derived from a comparison of Gaia DR2 with other radial velocity catalogs
Jack, Dennis
Using the recently published Gaia second data release that includes measurements of the mean radial velocity of about 7.2 million stars, we performed a systematic comparison with other existing radial velocity catalogs to search for variations in the radial velocity measurements, with the goal that detected differences may indicate that these star…
High-resolution spectroscopy of Boyajian's star during optical dimming events
Simón-Díaz, S.; Collier Cameron, A.; González Hernández, J. I. +13 more
Boyajian's star is an apparently normal main-sequence F-type star with a very unusual light curve. The dipping activity of the star, discovered during the Kepler mission, presents deep, asymmetric, and aperiodic events. Here we present high-resolution spectroscopic follow-up during some dimming events recorded post-Kepler observations, from ground…
MegaPipe 2.0: 10000 Square Degrees of CFHT MegaCam Imaging
Gwyn, Stephen
MegaPipe, the MegaCam data processing pipeline at the CADC, has been upgraded to version 2.0 and has processed over 10000 square degrees of the sky. MegaPipe has been operating since 2008. It was originally intended to increase the usage of archival MegaCam data by calibrating and stacking the images as they became public. That focus expanded to i…
OGLE-2015-BLG-1649Lb: A Gas Giant Planet around a Low-mass Dwarf
Bennett, D. P.; Soszyński, I.; Udalski, A. +70 more
We report the discovery of an exoplanet from the analysis of the gravitational microlensing event OGLE-2015-BLG-1649 that challenges the core accretion model of planet formation and appears to support the disk instability model. The planet/host-star mass ratio is q = 7.2 × 10-3 and the projected separation normalized to the angular Eins…
X-ray analysis of the accreting supermassive black hole in the radio galaxy PKS 2251+11
Tombesi, F.; Panessa, F.; Bruni, G. +2 more
Context. We have investigated the dichotomy between jetted and non-jetted active galactic nuclei (AGNs), focusing on the fundamental differences of these two classes in the accretion physics onto the central supermassive black hole (SMBH). We tested the validity of the unification model of AGNs through the characterization of the mutual interactio…
Parameter estimation for scarce stellar populations
Bitsakis, T.; Bruzual, G.; Cervantes Sodi, B. +1 more
We present a Bayesian method to determine simultaneously the age, metallicity, distance modulus, and interstellar reddening by dust of any resolved stellar population, by comparing the observed and synthetic colour magnitude diagrams on a star by star basis, with no need to bin the data into a carefully selected magnitude grid. We test the method …
Reprint of "Evidence for color dichotomy in the primordial Neptunian Trojan population"
Smith, M.; D'Andrea, C. B.; Abbott, T. M. C. +45 more
In the current model of early Solar System evolution, the stable members of the Jovian and Neptunian Trojan populations were captured into resonance from the leftover reservoir of planetesimals during the outward migration of the giant planets. As a result, both Jovian and Neptunian Trojans share a common origin with the primordial disk population…
A Recipe for Finding Stellar Radii, Temperatures, Surface Gravities, Metallicities, and Masses Using Spectral Lines
Gray, David F.; Kaur, Taranpreet
A recipe based on physical principles employs the observed equivalent widths of 10 spectral lines to model the photosphere of a target star. Coupled with the visual magnitude and an absolute flux calibration, the recipe yields the angular radius, effective temperature, surface gravity, and metallicity. With the addition of a parallax, a linear rad…
Optical Spectrum of Distant OH/IR Star V1648 Aql (IRAS 19386+0155)
Klochkova, V. G.; Tavolzhanskaya, N. S.
We present an optical spectrum of the star V1648 Aql (IRAS19386+0155) obtained at the 6-m SAO RAS telescope with a spectral resolution of R ≥ 60 000. Heliocentric radial velocity was measured from numerous metal absorptions is Vr = 10.18 ± 0.05 km s-1 (VLSR = 18.1 km s-1). We determined the atmospheric, …