Search Publications
Classification of 3 accreting binaries with VLT/X-Shooter spectra
Chaty, S.; Tomsick, J. A.; Fortin, F. +1 more
Since its launch, the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) satellite has discovered hundreds of X-ray sources, many of which lack proper classification. This mission also led to the discovery of new categories of high mass X-ray binaries (HMXB). We use the spectra of the X-Shooter instrument at the Very Large Telescope (VLT) …
Ultraviolet to far infrared self-consistent analysis of the stellar populations of massive starburst galaxies at intermediate redshifts
Pérez-González, Pablo G.; Zamorano, Jaime; Espino-Briones, Néstor +1 more
We study in detail the properties of the stellar populations of 111 massive [log (M⋆/M⊙) ≥ 10] dusty [far-infrared (FIR)-selected] starburst (SFR/SFRMS > 2) galaxies at 0.7 < z < 1.2. For that purpose, we use self-consistent methods that analyse the UV-to-FIR broad-band observations in terms of the stellar…
Spatially dependent photometric activity of M dwarfs in the solar cylinder
Wolf, Christian; Onken, Christopher A.; Chang, Seo-Won
We study the relationship between Galactic location (R, Z) and photometric activity for 3.6 million M dwarf stars within 1 kpc of the Sun. For this purpose, we identify 906 unique flare events as a proxy for magnetic activity from the SkyMapper Southern Survey Data Release 3. We adopt vertical distance |Z| from the Galactic disc as a proxy for age…
Parameters of the eclipsing binary α Draconis observed by TESS and SONG
Kochukhov, Oleg; Bedding, Timothy R.; Murphy, Simon J. +9 more
We present an analysis of the eclipsing single-lined spectroscopic binary system α Dra based on photometry from the Transiting Exoplanet Survey Satellite (TESS) mission and newly acquired spectroscopic measurements. Recently discovered to have eclipses in the TESS data, at a magnitude of V = 3.7, α Dra is now one of the brightest detached eclipsin…
An optimized survey strategy for the ERIS/NIX imager: searching for young giant exoplanets and very low mass brown dwarfs using the K-peak custom photometric filter
Allers, Katelyn; Kenworthy, Matthew A.; Bonavita, Mariangela +5 more
We present optimal survey strategies for the upcoming NIX imager, part of the Enhanced Resolution Imager and Spectrograph instrument to be installed on the Very Large Telescope. We will use a custom 2.2 µm K-peak filter to optimize the efficiency of a future large-scale direct imaging survey, aiming to detect brown dwarfs and giant planets around …
A TESS search for donor-star pulsations in high-mass X-ray binaries
Ramsay, Gavin; Hakala, Pasi; Charles, Philip A.
Ground-based optical photometry of the counterparts of high-mass X-ray binaries (HMXBs) has revealed the presence of periodic modulations on time-scales of ~0.3-0.5 d. More recent space-based observations (CoRoT and TESS) of OB and Be stars have shown that pulsations caused by p and g modes are common in early-type stars. We have therefore underta…
Magnetic field measurements of sharp-lined Ap stars
Ilyin, I.; Hubrig, S.; Schöller, M. +2 more
Previous observations suggested that Ap and Bp stars exhibit a bimodal distribution of surface magnetic field strengths and that actually only few or no stars exist with magnetic dipole field strengths below 300 G down to a few Gauss. As the number of Ap and Bp stars currently known to possess weak magnetic fields is not large, it is necessary to …
Near-infrared detection of H2 flows in the core of the Mon R1 association
Movsessian, T. A.; Andreasyan, H. R.; Tatarnikov, A. M. +1 more
We report the discovery of four new H2 jets in the Mon R1 star-forming region in images obtained with the 2.5-m telescope of the Caucasian Mountain Observatory of Sternberg Astronomical Institute (SAI), Moscow State University (MSU) through a filter centred on the H2 1-0 S(1) emission line. This discovery confirms the nature …
Extending the energy range of AstroSat-CZTI up to 380 keV with compton spectroscopy
Rao, A. R.; Bhalerao, Varun; Mithun, N. P. S. +4 more
The CZTI (Cadmium Zinc Telluride Imager) onboard AstroSat is a high energy coded mask imager and spectrometer in the energy range of 20-100 keV. Above 100 keV, the dominance of Compton scattering cross-section in CZTI results in a significant number of 2-pixel Compton events and these have been successfully utilized for polarization analysis of Cr…
The MOSDEF survey: a new view of a remarkable z = 1.89 merger
Siana, Brian; Shapley, Alice E.; Reddy, Naveen A. +13 more
We present a detailed study of a galaxy merger taking place at z = 1.89 in the GOODS-S field. Here, we analyse Keck/MOSFIRE spectroscopic observations from the MOSFIRE Deep Evolution Field (MOSDEF) survey along with multiwavelength photometry assembled by the 3D-HST survey. The combined data set is modelled to infer the past star formation histori…