Search Publications
An In Situ Study of Turbulence near Stellar Bow Shocks
Chatterjee, Shami; Dolch, Timothy; Cordes, James M. +1 more
Stellar bow shocks are observed in a variety of interstellar environments and shaped by the conditions of gas in the interstellar medium (ISM). In situ measurements of turbulent density fluctuations near stellar bow shocks are only achievable with a few observational probes, including Hα-emitting bow shocks and the Voyager Interstellar Mission (VI…
The local dark sector
Rhodes, Jason; Bergé, Joel; Pernot-Borràs, Martin +18 more
We speculate on the development and availability of new innovative propulsion techniques in the 2040s, that will allow us to fly a spacecraft outside the Solar System (at 150 AU and more) in a reasonable amount of time, in order to directly probe our (gravitational) Solar System neighborhood and answer pressing questions regarding the dark sector …
Variation of the core lifetime and fragmentation scale in molecular clouds as an indication of ambipolar diffusion
André, Philippe; Das, Indrani; Basu, Shantanu
Ambipolar diffusion likely plays a pivotal role in the formation and evolution of dense cores in weakly ionized molecular clouds. Linear analyses show that the evolutionary times and fragmentation scales are significantly greater than the hydrodynamic (Jeans) values even for clouds with mildly supercritical mass-to-flux ratios. We use values of fr…
Absorption-selected galaxies trace the low-mass, late-type, star-forming population at z 2-3
Valentino, F.; Fynbo, J. P. U.; Christensen, L. +5 more
We report on the stellar content, half-light radii and star formation rates of a sample of 10 known high-redshift (z ≳ 2) galaxies selected on strong neutral hydrogen (H I) absorption ($\log ({\rm N_{H\, \rm {I}}\: /\: cm}^{-2})\,\gt\, 19$) towards background quasars. We use observations from the Hubble Space Telescope Wide Field Camera 3 in three…
Resolved spectral variations of the centimetre-wavelength continuum from the ρ Oph W photodissociation region
Hensley, Brandon; Casassus, Simon; White, Glenn J. +5 more
Centimetre-wavelength radio continuum emission in excess of free-free, synchrotron, and Rayleigh-Jeans dust emission (excess microwave emission, EME), and often called 'anomalous microwave emission', is bright in molecular cloud regions exposed to UV radiation, i.e. in photodissociation regions (PDRs). The EME correlates with infrared (IR) dust em…
The relationship between gas and galaxies at z < 1 using the Q0107 quasar triplet
Tejos, Nicolas; Beckett, Alexander; Morris, Simon L. +5 more
We study the distribution and dynamics of the circumgalactic and intergalactic medium using a dense galaxy survey covering the field around the Q0107 system, a unique z ≈ 1 projected quasar triplet. With full Ly α coverage along all three lines-of-sight from z = 0.18 to z = 0.73, more than 1200 galaxy spectra, and two MUSE fields, we examine the s…
Spatial and Kinematic Clustering of Stars in the Galactic Disk
Conroy, Charlie; Ting, Yuan-Sen; El-Badry, Kareem +1 more
The Galactic disk is expected to be spatially and kinematically clustered on many scales due to both star formation and the Galactic potential. In this work we calculate the spatial and kinematic two-point correlation functions (TPCF) using a sample of 1.7 × 106 stars with radial velocities from Gaia DR2. Clustering is detected on spati…
Eight more low luminosity globular clusters in the Sagittarius dwarf galaxy
Minniti, D.; Saito, R. K.; Alonso-García, J. +2 more
Context. The Sagittarius (Sgr) dwarf galaxy is merging with the Milky Way, and the study of its globular clusters (GCs) is important to understand the history and outcome of this ongoing process.
Aims: Our main goal is to characterize the GC system of the Sgr dwarf galaxy. This task is hampered by high foreground stellar contamination, mostly…
Multiwavelength detectability of isolated black holes in the Milky Way
Bertone, Gianfranco; Connors, Riley; Ricotti, Massimo +3 more
Isolated black holes in our Galaxy have eluded detection so far. We present here a comprehensive study on the detectability of isolated stellar-mass astrophysical black holes that accrete interstellar gas from molecular clouds in both the local region and the Central Molecular Zone. We adopt a state-of-the-art model for the accretion physics backe…
Blocks Size Frequency Distribution in the Enceladus Tiger Stripes Area: Implications on Their Formative Processes
Lucchetti, Alice; Pajola, Maurizio; Cremonese, Gabriele +1 more
We study the size frequency distribution of the blocks located in the deeply fractured, geologically active Enceladus South Polar Terrain with the aim to suggest their formative mechanisms. Through the Cassini ISS images, we identify ~17,000 blocks with sizes ranging from ~25 m to 366 m, and located at different distances from the Damascus, Baghda…