Search Publications
JCMT POL-2 and BISTRO Survey Observations of Magnetic Fields in the L1689 Molecular Cloud
Pattle, Kate; Ward-Thompson, Derek; Bastien, Pierre +26 more
We present 850 µm polarization observations of the L1689 molecular cloud, part of the nearby Ophiuchus molecular cloud complex, taken with the POL-2 polarimeter on the James Clerk Maxwell Telescope (JCMT). We observe three regions of L1689: the clump L1689N which houses the IRAS 16293-2433 protostellar system, the starless clump SMM-16, and …
Prospects for Galactic and stellar astrophysics with asteroseismology of giant stars in the TESS continuous viewing zones and beyond
Chaplin, William J.; Girardi, Léo; van Saders, Jennifer L. +30 more
The NASA Transiting Exoplanet Survey Satellite (NASA-TESS) mission presents a treasure trove for understanding the stars it observes and the Milky Way, in which they reside. We present a first look at the prospects for Galactic and stellar astrophysics by performing initial asteroseismic analyses of bright (G < 11) red giant stars in the TESS s…
Evolution of Galaxy Star Formation and Metallicity: Impact on Double Compact Object Mergers
Danese, L.; Lapi, A.; Donevski, D. +3 more
In this paper, we study the impact of different galaxy statistics and empirical metallicity scaling relations on the merging rates and properties of compact object binaries. Firstly, we analyze the similarities and differences of using the star formation rate functions versus stellar mass functions as galaxy statistics for the computation of cosmi…
Empirical mass-loss rates and clumping properties of Galactic early-type O supergiants
Puls, J.; de Koter, A.; Sana, H. +7 more
Aims: We investigate the impact of optically thick clumping on spectroscopic stellar wind diagnostics in O supergiants and constrain wind parameters associated with porosity in velocity space. This is the first time the effects of optically thick clumping have been investigated for a sample of massive hot stars, using models which include a f…
TESS Observations of Cepheid Stars: First Light Results
Smolec, R.; Szabados, L.; Christensen-Dalsgaard, J. +33 more
We present the first analysis of Cepheid stars observed by the TESS space mission in Sectors 1-5. Our sample consists of 25 pulsators: ten fundamental mode, three overtone and two double-mode classical Cepheids, plus three type II and seven anomalous Cepheids. The targets were chosen from fields with different stellar densities, both from the Gala…
Deblending galaxies with variational autoencoders: A joint multiband, multi-instrument approach
LSST Dark Energy Science Collaboration; Aubourg, Eric; Doux, Cyrille +2 more
Blending of galaxies has a major contribution in the systematic error budget of weak-lensing studies, affecting photometric and shape measurements, particularly for ground-based, deep, photometric galaxy surveys, such as the Rubin Observatory Legacy Survey of Space and Time (LSST). Existing deblenders mostly rely on analytic modelling of galaxy pr…
The Rossiter-McLaughlin effect revolutions: an ultra-short period planet and a warm mini-Neptune on perpendicular orbits
Rebolo, R.; Zapatero Osorio, M. R.; Scandariato, G. +34 more
Comparisons of the alignment of exoplanets with a common host star and each other can be used to distinguish among concurrent evolution scenarios for the star and the planets. However, multi-planet systems usually host mini-Neptunes and super-Earths, whose sizes make orbital architecture measurements challenging. We introduce the Rossiter-McLaughl…
The S2 stream: the shreds of a primitive dwarf galaxy
Myeong, G. C.; Belokurov, Vasily; Matteucci, Francesca +12 more
The S2 stream is a kinematically cold stream that is plunging downwards through the Galactic disc. It may be part of a hotter and more diffuse structure called the Helmi stream. We present a multi-instrument chemical analysis of the stars in the metal-poor S2 stream using both high- and low-resolution spectroscopy, complemented with a re-analysis …
The properties of the AGN torus as revealed from a set of unbiased NuSTAR observations
Ajello, M.; Marchesi, S.; Torres-Albà, N. +4 more
The obscuration observed in active galactic nuclei (AGNs) is mainly caused by dust and gas distributed in a torus-like structure surrounding the supermassive black hole. However, the properties of the obscuring torus of an AGN in X-ray have not yet been fully investigated because of a lack of high-quality data and proper models. In this work, we p…
Deriving CME Density From Remote Sensing Data and Comparison to In Situ Measurements
Temmer, M.; Veronig, A. M.; Vršnak, B. +8 more
We determine the three dimensional geometry and deprojected mass of 29 well observed coronal mass ejections (CMEs) and their interplanetary counterparts (ICMEs) using combined Solar Terrestrial Relations Observatory Solar and Heliospheric Observatory white light data. From the geometry parameters, we calculate the volume of the CME for the magneti…