Search Publications
On the Oosterhoff dichotomy in the Galactic bulge - II. Kinematical distribution
Smolec, R.; Grebel, E. K.; Catelan, M. +3 more
We present a kinematical study of RR Lyrae stars associated with two Oosterhoff groups in the Galactic bulge. We used data published in the first paper of the series, plus proper motions from the Gaia Data Release 2, and radial velocities from the literature. A 6D kinematical and spatial solution was obtained for 429 RR Lyrae stars. We use a model…
Space astrometry of the very massive ∼150 M⊙ candidate runaway star VFTS682
Lennon, D. J.; Renzo, M.; Platais, I. +12 more
How very massive stars form is still an open question in astrophysics. VFTS682 is among the most massive stars known, with an inferred initial mass of ≳150 M_⊙. It is located in 30 Doradus at a projected distance of 29 pc from the central cluster R136. Its apparent isolation led to two hypotheses: either it formed in relative isolation or it was e…
Synthetic 26Al emission from galactic-scale superbubble simulations
Diehl, R.; Rodgers-Lee, D.; Krause, M. G. H. +1 more
Emission from the radioactive trace element 26Al has been observed throughout the Milky Way with the COMPTEL and INTEGRAL satellites. In particular, the Doppler shifts measured with INTEGRAL connect 26Al with superbubbles, which may guide 26Al flows off spiral arms in the direction of Galactic rotation. In order to…
WASP-147b, 160Bb, 164b, and 165b: two hot Saturns and two Jupiters, including two planets with metal-rich hosts
Bouchy, F.; Queloz, D.; Ségransan, D. +20 more
We report the discovery of four transiting hot Jupiters, WASP-147, WASP-160B, WASP-164, and WASP-165 from the WASP survey. WASP-147b is a near Saturn-mass (MP = 0.28MJ) object with a radius of 1.11 {{R}J} orbiting a G4 star with a period of 4.6 d. WASP-160Bb has a mass and radius (M_p = 0.28 {{M}J}, R_p …
On the existence of bright IR galaxies at z > 2: tension between Herschel and SCUBA-2 results?
Pozzi, Francesca; Gruppioni, Carlotta
Recent derivations of the galaxy star formation rate density (SFRD) obtained from sub-millimetre (sub-mm) surveys (e.g. SCUBA-2) show a tension with previous works based on Herschel and multi-wavelength data. Some of these works claim that the SFRD derived by pushing the Herschel surveys beyond z ≃ 2 are incorrect. However, the current sub-mm surv…
Building a cluster: shocks, cavities, and cooling filaments in the group-group merger NGC 6338
Vrtilek, Jan M.; David, Laurence P.; Sun, Ming +4 more
We present deep Chandra, XMM-Newton, Giant Metrewave Radio Telescope, and Hα observations of the group-group merger NGC 6338. X-ray imaging and spectral mapping show that as well as trailing tails of cool, enriched gas, the two cool cores are embedded in an extensive region of shock-heated gas with temperatures rising to ∼5 keV. The velocity distr…
Study of the long-term evolution of the accretion dynamics of GX 339-4
Mandal, S.; Aneesha, U.; Sreehari, H.
We study the dynamical behaviour of the galactic black hole source GX 339-4 during 2002-2011 outbursts using RXTE, Swift-XRT, XMM-Newton (PN) archival data. We present the spectral evolution of the source using four outburst data and discuss their similarities and differences between outbursts. We infer that the second peak in the 2002/03 and 2004…
Dynamics of wind and the dusty environments in the accreting T Tauri stars RY Tauri and SU Aurigae
Grankin, K. N.; Irsmambetova, T. R.; Gahm, G. F. +10 more
Classical T Tauri stars with ages of less than 10 Myr possess accretion discs. Magnetohydrodynamic processes at the boundary between the disc and the stellar magnetosphere control the accretion and ejections gas flows. We carried out a long series of simultaneous spectroscopic and photometric observations of the classical T Tauri stars, RY Tauri a…
Probability of magnification in the HubbleFrontier Fields clusters
Diego, J. M.; Bernstein, G. M.; Vega-Ferrero, J.
We present free-form gravitational lensing models derived with the WSLAP+ code for the six HubbleFrontier Fields clusters using the latest data available from the Frontier Fields Lensing Models v.4 collaboration. We present magnification maps in the lens plane and caustic maps in the source plane. From these maps, we derive the probability of magn…
Suppressed CO emission and high G/D ratios in z = 2 galaxies with sub-solar gas-phase metallicity
Daddi, E.; Béthermin, M.; Sargent, M. T. +6 more
We study a population of significantly sub-solar enrichment galaxies at z = 1.99, to investigate how molecular gas, dust, and star formation relate in low-metallicity galaxies at the peak epoch of star formation. We target our sample with several deep Atacama Large Millimeter/submillimeter Array and Very Large Array datasets, and find no individua…