Search Publications
A CEMP-no star in the ultra-faint dwarf galaxy Pisces II
Salvadori, S.; Bonifacio, P.; Caffau, E. +3 more
Aims: A probable carbon enhanced metal-poor (CEMP) star, Pisces II 10694, was discovered recently in the ultra-faint (UFD) galaxy Pisces II. This galaxy is supposed to be very old, suspected to include dark matter, and likely formed the bulk of its stars before the reionisation of the Universe.
Methods: New abundances have been obtained …
HERUS: the far-IR/submm spectral energy distributions of local ULIRGs and photometric atlas
Clements, D. L.; Farrah, D.; Rigopoulou, D. +9 more
We present the Herschel-SPIRE photometric atlas for a complete flux limited sample of 43 local ultraluminous infrared galaxies (ULIRGs), selected at 60 µm by IRAS, as part of the HERschel ULIRG Survey (HERUS). Photometry observations were obtained using the SPIRE instrument at 250, 350, and 500 µm. We describe these observations, prese…
The fall of the Northern Unicorn: tangential motions in the Galactic anticentre with SDSS and Gaia
Belokurov, V.; Koposov, S. E.; de Boer, T. J. L.
We present the first detailed study of the behaviour of the stellar proper motion across the entire Galactic anticentre area visible in the Sloan Digital Sky Survey (SDSS) data. We use recalibrated SDSS astrometry in combination with positions from Gaia DR1 to provide tangential motion measurements with a systematic uncertainty <5 km s-1
The James Webb Space Telescope North Ecliptic Pole Time-domain Field. I. Field Selection of a JWST Community Field for Time-domain Studies
Windhorst, Rogier A.; Jansen, Rolf A.
We describe the selection of the James Webb Space Telescope (JWST) North Ecliptic Pole (NEP) Time-domain Field (TDF), a ≳14‧ diameter field located within JWST’s northern continuous viewing zone (CVZ) and centered at (R.A., decl.)J2000 = (17:22:47.896, +65:49:21.54). We demonstrate that this is the only region in the sky where JWST can …
The vertical force in the solar neighbourhood using red clump stars in TGAS and RAVE. Constraints on the local dark matter density
Helmi, Amina; Hagen, Jorrit H. J.
Aims: We investigate the kinematics of red clump (RC) stars in the solar neighbourhood by combining data from Tycho-Gaia Astrometric Solution (TGAS) and Radial Velocity Experiment (RAVE) to constrain the local dark matter density.
Methods: After calibrating the absolute magnitude of RC stars, we characterized their velocity distribution …
The Variable Fast Soft X-Ray Wind in PG 1211+143
Reeves, J. N.; Pounds, K. A.; Lobban, A.
The analysis of a series of seven observations of the nearby (z = 0.0809) QSO PG 1211+143, taken with the Reflection Grating Spectrometer (RGS) onboard XMM-Newton in 2014, are presented. The high-resolution soft X-ray spectrum, with a total exposure exceeding 600 ks, shows a series of blueshifted absorption lines from the He and H-like transitions…
An Alternate Approach to Measure Specific Star Formation Rates at 2\lt z\lt 7
Ilbert, Olivier; Davidzon, Iary; Faisst, Andreas L. +2 more
We trace the specific star formation rate (sSFR) of massive star-forming galaxies (≳ {10}10 {{ M }}⊙ ) from z∼ 2 to 7. Our method is substantially different from previous analyses, as it does not rely on direct estimates of star formation rate, but on the differential evolution of the galaxy stellar mass function (SMF). We sh…
Pulsation-triggered dust production by asymptotic giant branch stars
Zijlstra, A. A.; De Beck, E.; McDonald, I. +1 more
Eleven nearby (<300 pc), short-period (50-130 d) asymptotic giant branch (AGB) stars were observed in the CO J = 2-1 line. Detections were made towards objects that have evidence for dust production (Ks - [22] ≳ 0.55 mag; AK Hya, V744 Cen, RU Crt, α Her). Stars below this limit were not detected (BQ Gem, ɛ Oct, NU Pav, II Hya, CL Hyi…
The Effect of Magnetic Variability on Stellar Angular Momentum Loss. I. The Solar Wind Torque during Sunspot Cycles 23 and 24
Finley, Adam J.; See, Victor; Matt, Sean P.
The rotational evolution of cool stars is governed by magnetized stellar winds that slow the stellar rotation during their main sequence lifetimes. Magnetic variability is commonly observed in Sun-like stars, and the changing strength and topology of the global field is expected to affect the torque exerted by the stellar wind. We present three di…
Detection of Quasi-Periodic Pulsations in Solar EUV Time Series
Zhukov, A. N.; Dolla, L.; Lapenta, G. +2 more
Quasi-periodic pulsations (QPPs) are intrinsically connected to the mechanism of solar flares. They are regularly observed in the impulsive phase of flares since the 1970s. In the past years, the studies of QPPs regained interest with the advent of a new generation of soft X-ray/extreme ultraviolet radiometers that pave the way for statistical sur…