Search Publications
Eclipsing Binaries in the Open Cluster Ruprecht 147. I. EPIC 219394517
Torres, Guillermo; Vanderburg, Andrew; Kraus, Adam L. +2 more
Eclipsing binaries in star clusters offer more stringent tests of stellar evolution theory than field binaries because models must not only match the binary properties, but also the radiative properties of all other cluster members at a single chemical composition and a single age. Here we report new spectroscopic observations of the G-type, detac…
The hyperluminous Compton-thick z ∼ 2 quasar nucleus of the hot DOG W1835+4355 observed by NuSTAR
Maiolino, R.; Fiore, F.; Bianchi, S. +11 more
We present a 155 ks NuSTAR observation of the z ∼ 2 hot dust-obscured galaxy (hot DOG) W1835+4355. We extracted spectra from the two NuSTAR detectors and analyzed them jointly with the archival XMM-Newton PN and MOS spectra. We performed a spectroscopic analysis based on both phenomenological and physically motivated models employing toroidal and …
The phase function and density of the dust observed at comet 67P/Churyumov-Gerasimenko
Lasue, J.; Jorda, L.; Lamy, P. L. +44 more
The OSIRIS camera onboard Rosetta measured the phase function of both the coma dust and the nucleus. The two functions have a very different slope versus the phase angle. Here, we show that the nucleus phase function should be adopted to convert the brightness to the size of dust particles larger than 2.5 mm only. This makes the dust bursts observ…
On the Kinematic Signature of the Galactic Warp As Revealed By the LAMOST-TGAS Data
Huang, Y.; Chen, B. -Q.; Wang, C. +6 more
Using a sample of about 123,000 stars with accurate 3D velocity measurements from the LAMOST-TGAS data, we confirm the kinematic signature of the Galactic warp recently found by Schönrich & Dehnen. The data reveal a clear trend of increasing mean vertical velocity \overline{{V}z} as a function of absolute vertical angular momentum L…
IGR J17329-2731: The birth of a symbiotic X-ray binary
Sanna, A.; Gandhi, P.; Romano, P. +10 more
We report on the results of the multiwavelength campaign carried out after the discovery of the INTEGRAL transient IGR J17329-2731. The optical data collected with the SOAR telescope allowed us to identify the donor star in this system as a late M giant at a distance of 2.7-1.2+3.4 kpc. The data collected quasi-simultaneously…
Models of Rosetta/OSIRIS 67P Dust Coma Phase Function
Lamy, P. L.; Lara, L. M.; Bertaux, J. -L. +39 more
The phase function of the dust coma of comet 67P has been determined from Rosetta/OSIRIS images. This function shows a deep minimum at phase angles near 100°, and a strong backscattering enhancement. These two properties cannot be reproduced by regular models of cometary dust, most of them based on wavelength-sized and randomly oriented aggregate …
On the observational diagnostics to separate classical and disk-like bulges
Costantin, Luca; Morelli, L.; Dalla Bontà, E. +3 more
Flattened bulges with disk-like properties are considered to be the end product of secular evolution processes at work in the inner regions of galaxies. On the contrary, classical bulges are characterized by rounder shapes and thought to be similar to low-luminosity elliptical galaxies. We aim at testing the variety of observational diagnostics wh…
The Orbital Architecture and Debris Disks of the HR 8799 Planetary System
Goździewski, Krzysztof; Migaszewski, Cezary
The HR 8799 planetary system with four ≃10 m Jup planets in wide orbits up to ≃70 au and orbital periods up to 500 yr has been detected with direct imaging. Its intriguing orbital architecture is not yet fully resolved due to time-limited astrometry covering only ≃20 yr. Earlier, we constructed a heuristic model of the system based on r…
Two-sided-loop Jets Associated with Magnetic Reconnection between Emerging Loops and Twisted Filament Threads
Chen, Yao; Huang, Zhenghua; Zheng, Ruisheng +3 more
Coronal jets are always produced by magnetic reconnection between emerging flux and pre-existing overlying magnetic fields. When the overlying field is vertical/oblique or horizontal, the coronal jet will appear as anemone type or two-sided-loop type. Most observational jets are of the anemone type, and only a few two-sided-loop jets have been rep…
The Minimum Mass of Rotating Main-sequence Stars and its Impact on the Nature of Extended Main-sequence Turnoffs in Intermediate-age Star Clusters in the Magellanic Clouds
Girardi, Léo; Bellini, Andrea; Goudfrooij, Paul +3 more
Extended main-sequence turnoffs (eMSTOs) are a common feature in color-magnitude diagrams (CMDs) of young and intermediate-age star clusters in the Magellanic Clouds. The nature of eMSTOs is still debated. The most popular scenarios are extended star formation and ranges of stellar rotation rates. Here, we study implications of a kink feature in t…