Search Publications
Time-resolved photometry of the young dipper RX J1604.3-2130A. Unveiling the structure and mass transport through the innermost disk
Bouvier, J.; Manara, C. F.; Pinilla, P. +3 more
Context. RX J1604.3-2130A is a young, dipper-type, variable star in the Upper Scorpius association, suspected to have an inclined inner disk, with respect to its face-on outer disk.
Aims: We aim to study the eclipses to constrain the inner disk properties.
Methods: We used time-resolved photometry from the Rapid Eye Mount telescope and K…
Crystalline silicate absorption at 11.1 µm: ubiquitous and abundant in embedded YSOs and the interstellar medium
Wright, Christopher M.; Fujiyoshi, Takuya; Siebenmorgen, Ralf +5 more
Utilizing several instruments on 4-8 m telescopes, we have observed a large sample of objects in the mid-infrared (8-13 µm). These comprise a few evolved stars, multiple envelopes of embedded young stellar objects (YSOs) or compact H-II regions, and several sightlines through the interstellar medium (ISM). The latter is where dust resides - …
The frequency of extreme X-ray variability for radio-quiet quasars
Brandt, W. N.; Liu, H.; Luo, B. +3 more
We analyse 1598 serendipitous Chandra X-ray observations of 462 radio-quiet quasars to constrain the frequency of extreme amplitude X-ray variability that is intrinsic to the quasar corona and innermost accretion flow. The quasars in this investigation are all spectroscopically confirmed, optically bright (mi ≤ 20.2), and contain no ide…
The Next Generation Virgo Cluster Survey. XXXIV. Ultracompact Dwarf Galaxies in the Virgo Cluster
Zhang, Hongxin; Liu, Chengze; Gwyn, Stephen +26 more
We present a study of ultracompact dwarf (UCD) galaxies in the Virgo cluster based mainly on imaging from the Next Generation Virgo Cluster Survey (NGVS). Using ∼100 deg2 of u*giz imaging, we have identified more than 600 candidate UCDs, from the core of Virgo out to its virial radius. Candidates have been selected through a combination…
A Tidal Disruption Event Candidate Discovered in the Active Galactic Nucleus SDSS J022700.77-042020.6
Lu, Youjun; Liu, Zhu; Yuan, Weimin +4 more
We report the discovery of a tidal disruption event (TDE) candidate occurring in the active galactic nucleus (AGN) SDSS J022700.77-042020.6. A sudden increase in flux from J0227-0420 during the second half of 2009 appears in the long-term optical, UV, and near-IR (NIR) light curves. A plateau phase, following an initial decline, is seen in the nea…
Bar resonances and low angular momentum moving groups in the Galaxy revealed by their stellar ages
Laporte, Chervin F. P.; Famaey, Benoit; Gerhard, Ortwin +3 more
We use the second Gaia data release to dissect the Milky Way disc in phase-space and relative ages. We confirm and report the existence of multiple velocity moving groups at low azimuthal velocities and angular momenta, below Arcturus, regularly separated by ∼18-20 km s-1 in azimuthal velocity. Such features were predicted to exist more…
The challenge of measuring the phase function of debris discs. Application to HR 4796 A
Bayo, A.; Henning, Th.; Milli, J. +2 more
Context. Debris discs are valuable systems to study dust properties. Because they are optically thin at all wavelengths, we have direct access to the absorption and scattering properties of the dust grains. One very promising technique to study them is to measure their phase function, that is, the scattering efficiency as a function of the scatter…
Estimating the Ultraviolet Emission of M Dwarfs with Exoplanets from Ca II and Hα
Loyd, R. O. Parke; Peacock, Sarah; Redfield, Seth +29 more
M dwarf stars are excellent candidates around which to search for exoplanets, including temperate, Earth-sized planets. To evaluate the photochemistry of the planetary atmosphere, it is essential to characterize the UV spectral energy distribution of the planet's host star. This wavelength regime is important because molecules in the planetary atm…
Gaia's detectability of black hole-main sequence star binaries formed in open clusters
Fujii, Michiko S.; Kumamoto, Jun; Shikauchi, Minori +1 more
Black hole-main sequence star (BH-MS) binaries are one of the targets of future data releases of the astrometric satellite Gaia. They are supposed to be formed in two main sites: a galactic field and star clusters. However, previous work has never predicted the number of BH-MS binaries originating in the latter sites. In this paper we estimate the…
Using radio triangulation to understand the origin of two subsequent type II radio bursts
Jebaraj, I. C.; Magdalenić, J.; Kilpua, E. K. J. +7 more
Context. Eruptive events such as coronal mass ejections (CMEs) and flares accelerate particles and generate shock waves which can arrive at Earth and can disturb the magnetosphere. Understanding the association between CMEs and CME-driven shocks is therefore highly important for space weather studies.
Aims: We present a study of the CME/flare…