Search Publications
A cool and inflated progenitor candidate for the Type Ib supernova 2019yvr at 2.6 yr before explosion
Kilpatrick, Charles D.; Drout, Maria R.; Foley, Ryan J. +13 more
We present Hubble Space Telescope imaging of a pre-explosion counterpart to SN 2019yvr obtained 2.6 yr before its explosion as a type Ib supernova (SN Ib). Aligning to a post-explosion Gemini-S/GSAOI image, we demonstrate that there is a single source consistent with being the SN 2019yvr progenitor system, the second SN Ib progenitor candidate aft…
Investigating the young AU Mic system with SPIRou: large-scale stellar magnetic field and close-in planet mass
Gaidos, Eric; Doyon, René; Donati, Jean-François +12 more
We present a velocimetric and spectropolarimetric analysis of 27 observations of the 22-Myr M1 star AU Microscopii (AU Mic) collected with the high-resolution YJHK (0.98-2.35 µm) spectropolarimeter SPIRou from 2019 September 18 to November 14. Our radial velocity (RV) time-series exhibits activity-induced fluctuations of 45 m s-1 …
APOGEE DR16: A multi-zone chemical evolution model for the Galactic disc based on MCMC methods
Calura, F.; Palla, M.; Matteucci, F. +6 more
Context. The analysis of the latest release of the Apache Point Observatory Galactic Evolution Experiment project (APOGEE DR16) data suggests the existence of a clear distinction between two sequences of disc stars at different Galactocentric distances in the [α/Fe] versus [Fe/H] abundance ratio space: the so-called high-α sequence, classically as…
The Hi-GAL compact source catalogue - II. The 360° catalogue of clump physical properties
Martin, P. G.; Paladini, R.; Pilbratt, G. L. +29 more
We present the 360° catalogue of physical properties of Hi-GAL compact sources, detected between 70 and 500 $\mu$m. This release not only completes the analogous catalogue previously produced by the Hi-GAL collaboration for -71° ≲ ℓ ≲ 67°, but also meaningfully improves it because of a new set of heliocentric distances, 120 808 in total. About a t…
Primordial black holes and scalar-induced secondary gravitational waves from inflationary models with a noncanonical kinetic term
Gao, Qing; Gong, Yungui; Yi, Zhu +1 more
With the enhancement mechanism provided by a noncanonical kinetic term with a peak, the amplitude of primordial curvature perturbations can be enhanced by seven orders of magnitude at small scales while keeping to be consistent with observations at large scales. The peak function and inflationary potential are not restricted in this mechanism. We …
Turbulent Gas in Lensed Planck-selected Starbursts at z ∼ 1-3.5
Frayer, D. T.; Frye, B. L.; Jiménez-Andrade, E. F. +26 more
Dusty star-forming galaxies at high redshift (1 < z < 3) represent the most intense star-forming regions in the universe. Key aspects to these processes are the gas heating and cooling mechanisms, and although it is well known that these galaxies are gas-rich, little is known about the gas excitation conditions. Only a few detailed radiative…
Extending the evolution of the stellar mass-size relation at z ≤ 2 to low stellar mass galaxies from HFF and CANDELS
Ferguson, Henry C.; Kartaltepe, Jeyhan S.; Martis, Nicholas S. +23 more
We reliably extend the stellar mass-size relation over 0.2 ≤ z ≤ 2 to low stellar mass galaxies by combining the depth of Hubble Frontier Fields with the large volume covered by CANDELS. Galaxies are simultaneously modelled in multiple bands using the tools developed by the MegaMorph project, allowing robust size (i.e. half-light radius) estimates…
Validation of the Gaia Early Data Release 3 Parallax Zero-point Model with Asteroseismology
Zinn, Joel C.
Gaia Early Data Release 3 (EDR3) provides trigonometric parallaxes for 1.5 billion stars, with reduced systematics compared to Gaia Data Release 2 and reported precisions better by up to a factor of 2. New to EDR3 is a tentative model for correcting the parallaxes of magnitude-, position-, and color-dependent systematics for five- and six-paramete…
Elevated r-process Enrichment in Gaia Sausage and Sequoia
Myeong, G. C.; Kobayashi, Chiaki; Belokurov, Vasily +6 more
The Gaia Sausage (GS) and the Sequoia represent the major accretion events that formed the stellar halo of the Milky Way. A detailed chemical study of these main building blocks provides a pristine view of the early steps of the Galaxy's assembly. We present the results of the analysis of the UVES high-resolution spectroscopic observations at the …
Solar force-free magnetic fields
Wiegelmann, Thomas; Sakurai, Takashi
The structure and dynamics of the solar corona is dominated by the magnetic field. In most areas in the corona magnetic forces are so dominant that all non-magnetic forces such as plasma pressure gradients and gravity can be neglected in the lowest order. This model assumption is called the force-free field assumption, as the Lorentz force vanishe…