Search Publications
Discovery and characterization of five new eclipsing AM CVn systems
Kulkarni, S. R.; Rusholme, B.; Goldstein, D. A. +19 more
AM CVn systems are ultra-compact, hydrogen-depleted, and helium-rich, accreting binaries with degenerate or semidegenerate donors. We report the discovery of five new eclipsing AM CVn systems with orbital periods of 61.5, 55.5, 53.3, 37.4, and 35.4 min. These systems were discovered by searching for deep eclipses in the Zwicky Transient Facility (…
Intermediate- and high-velocity clouds in the Milky Way - II. Evidence for a Galactic fountain with collimated outflows and diffuse inflows
Lehner, Nicolas; Howk, J. Christopher; Marasco, Antonino +1 more
We model the kinematics of the high- and intermediate-velocity clouds (HVCs and IVCs) observed in absorption towards a sample of 55 Galactic halo stars with accurate distance measurements. We employ a simple model of a thick disc whose main free parameters are the gas azimuthal, radial, and vertical velocities (vϕ, vR, and v<…
Evidence for Cold-stream to Hot-accretion Transition as Traced by Lyα Emission from Groups and Clusters at 2 < z < 3.3
Finoguenov, A.; Daddi, E.; Elbaz, D. +12 more
We present Keck Cosmic Web Imager observations of giant Lyα halos surrounding nine galaxy groups and clusters at 2 < z < 3.3, including five new detections and one upper limit. We find observational evidence for the cold-stream to hot-accretion transition predicted by theory by measuring a decrease in the ratio between the spatially extended…
Lyman alpha and Lyman continuum emission of Mg II-selected star-forming galaxies
Chisholm, J.; Schaerer, D.; Izotov, Y. I. +3 more
We present observations with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope of seven compact low-mass star-forming galaxies at redshifts, z, in the range 0.3161-0.4276, with various O3Mg2 = [O III] λ5007/Mg II λ2796+2803 and Mg2 = Mg II λ2796/Mg II λ2803 emission-line ratios. We aim to study the…
Further Evidence of Modified Spin-down in Sun-like Stars: Pileups in the Temperature-Period Distribution
Angus, Ruth; van Saders, Jennifer L.; Zinn, Joel C. +5 more
We combine stellar surface rotation periods determined from NASA's Kepler mission with spectroscopic temperatures to demonstrate the existence of pileups at the long-period and short-period edges of the temperature-period distribution for main-sequence stars with temperatures exceeding ~5500 K. The long-period pileup is well described by a curve o…
Understanding star formation in molecular clouds. IV. Column density PDFs from quiescent to massive molecular clouds
André, Ph.; Arzoumanian, D.; Könyves, V. +26 more
Probability distribution functions of the total hydrogen column density (N-PDFs) are a valuable tool for distinguishing between the various processes (turbulence, gravity, radiative feedback, magnetic fields) governing the morphological and dynamical structure of the interstellar medium. We present N-PDFs of 29 Galactic regions obtained from Hersc…
The 700 ks Chandra Spiderweb Field. I. Evidence for widespread nuclear activity in the protocluster
Pannella, M.; Fiore, F.; Pentericci, L. +21 more
Aims: We present an analysis of the 700 ks Chandra ACIS-S observation of the field around the radio galaxy J1140-2629 (the Spiderweb Galaxy) at z = 2.156, focusing on the nuclear activity in the associated large-scale environment.
Methods: We identified unresolved X-ray sources in the field down to flux limits of 1.3 × 10−16 a…
Assessment of [Fe/H] determinations for FGK stars in spectroscopic surveys
Casamiquela, L.; Soubiran, C.; Brouillet, N.
Context. The iron abundance [Fe/H] in the atmosphere of FGK-type stars is crucial in stellar and galactic physics. The number of stars with a measured value of [Fe/H] is increasing considerably thanks to spectroscopic surveys. However, different methodologies, inputs, and assumptions used in spectral analyses lead to different precisions in [Fe/H]…
The VMC survey - XLVIII. Classical cepheids unveil the 3D geometry of the LMC
Girardi, Léo; Chemin, Laurent; de Grijs, Richard +12 more
We employed the VISTA near-infrared YJKssurvey of the Magellanic System (VMC) to analyse the $Y,\, J,~\mathrm{ and}~ K_\mathrm{s}$ light curves of δ Cepheid stars (DCEPs) in the Large Magellanic Cloud (LMC). Our sample consists of 4408 objects accounting for 97 per cent of the combined list of OGLE IV and Gaia DR2 DCEPs. We determined a…
The Lensed Lyman-Alpha MUSE Arcs Sample (LLAMAS). I. Characterisation of extended Lyman-alpha halos and spatial offsets
Bauer, F. E.; Richard, J.; Verhamme, A. +17 more
Aims: We present the Lensed Lyman-Alpha MUSE Arcs Sample (LLAMAS) selected from MUSE and HST observations of 17 lensing clusters. The sample consists of 603 continuum-faint (−23 < MUV < −14) lensed Lyman-α emitters (producing 959 images) with secure spectroscopic redshifts between 2.9 and 6.7. Combining the power of cluster m…