Search Publications
MIKiS: The Multi-instrument Kinematic Survey of Galactic Globular Clusters. I. Velocity Dispersion Profiles and Rotation Signals of 11 Globular Clusters
Dalessandro, E.; Valenti, E.; Bellazzini, M. +10 more
We present the first results of the Multi-Instrument Kinematic Survey of Galactic Globular Clusters (GGCs), a project aimed at exploring the internal kinematics of a representative sample of GGCs from the radial velocity of individual stars, covering the entire radial extension of each system. This is achieved by exploiting the formidable combinat…
Microphysics of KCl and ZnS Clouds on GJ 1214 b
Benneke, Björn; Gao, Peter
Clouds in the atmospheres of exoplanets confound characterization efforts by reducing, eliminating, and distorting the spectral signatures of molecular abundances. As such, interpretations of exoplanet spectra strongly depend on the choice of cloud model, many of which are highly simplified and lack predictive power. In this work, we use a cloud m…
Spatially Resolved Stellar Kinematics from LEGA-C: Increased Rotational Support in z ∼ 0.8 Quiescent Galaxies
Bell, Eric F.; Maseda, Michael V.; Franx, Marijn +18 more
We present stellar rotation curves and velocity dispersion profiles for 104 quiescent galaxies at z = 0.6-1 from the Large Early Galaxy Astrophysics Census (LEGA-C) spectroscopic survey. Rotation is typically probed across 10-20 kpc, or to an average of 2.7Re. Combined with central stellar velocity dispersions (σ0) this provi…
Resolving Quiescent Galaxies at z ≳ 2. II. Direct Measures of Rotational Support
Ellis, Richard S.; Belli, Sirio; Newman, Andrew B. +1 more
Stellar kinematics provide insights into the masses and formation histories of galaxies. At high redshifts, spatially resolving the stellar kinematics of quiescent galaxies is challenging due to their compact sizes. Using deep near-infrared spectroscopy, we have measured the resolved stellar kinematics of four quiescent galaxies at z = 1.95-2.64, …
A Gap in the Lower Main Sequence Revealed by Gaia Data Release 2
Gies, Douglas R.; Henry, Todd J.; Jao, Wei-Chun +1 more
We present the discovery of a gap near M G ≈ 10 in the main sequence on the Hertzsprung-Russell Diagram (HRD) based on measurements presented in Gaia Data Release 2 (DR2). Using an observational form of the HRD with M G representing luminosity and G BP - G RP representing temperature, the gap present…
Intermediate-mass Elements in Young Supernova Remnants Reveal Neutron Star Kicks by Asymmetric Explosions
Katsuda, Satoru; Janka, Hans-Thomas; Tominaga, Nozomu +9 more
The birth properties of neutron stars (NSs) yield important information about the still-debated physical processes that trigger the explosion as well as on intrinsic neutron-star physics. These properties include the high space velocities of young neutron stars with average values of several 100 km s-1, with an underlying “kick” mechani…
Exploring the Effects of Disk Thickness on the Black Hole Reflection Spectrum
Reynolds, Christopher S.; Taylor, Corbin
The relativistically broadened reflection spectrum, observed in both AGN and X-ray binaries, has proven to be a powerful probe of the properties of black holes and the environments in which they reside. Emitted from the innermost regions of the accretion disk, this X-ray spectral component carries with it information not only about the plasma that…
The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XV. The Dynamical Clock: Reading Cluster Dynamical Evolution from the Segregation Level of Blue Straggler Stars
Dalessandro, E.; Salaris, M.; Anderson, J. +17 more
The parameter A +, defined as the area enclosed between the cumulative radial distribution of blue straggler stars (BSSs) and that of a reference population, is a powerful indicator of the level of BSS central segregation. As part of the Hubble Space Telescope UV Legacy Survey of Galactic globular clusters (GCs), here we present the BSS…
ALMA Detection of Extended [C II] Emission in Himiko at z = 6.6
Maiolino, R.; Amorín, R.; Smit, R. +1 more
Himiko is one of the most luminous Lyα emitters at z = 6.595. It has three star-forming clumps detected in the rest-frame UV, with a total SFR = 20 M ⊙ yr-1. We report the Atacama Large Millimeter/submillimeter Array (ALMA) detection of the [C II]158 µm line emission in this Galaxy with a significance of 8σ. The total […
A Comparison of the X-Ray Emission from Tidal Disruption Events with those of Active Galactic Nuclei
Ramirez-Ruiz, Enrico; Auchettl, Katie; Guillochon, James
One of the main challenges of current tidal disruption events (TDEs) studies is that emission arising from active galactic nucleus (AGN) activity may potentially mimic the expected X-ray emission of a TDE. Here we compare the X-ray properties of TDEs and AGNs to determine a set of characteristics that would allow us to discriminate between flares …