Search Publications
On the Use of Field RR Lyrae as Galactic Probes. I. The Oosterhoff Dichotomy Based on Fundamental Variables
Valenti, E.; Marinoni, S.; Thévenin, F. +21 more
We collected a large data set of field RR Lyrae stars (RRLs) by using catalogs already available in the literature and Gaia DR2. We estimated the iron abundances for a subsample of 2382 fundamental RRLs (ΔS method: Ca II K, Hβ, Hγ, and Hδ lines) for which there are publicly available medium-resolution SDSS-SEGUE spectra. We also included similar e…
GROWTH on S190426c: Real-time Search for a Counterpart to the Probable Neutron Star-Black Hole Merger using an Automated Difference Imaging Pipeline for DECam
Duev, Dmitry A.; Andreoni, Igor; De, Kishalay +17 more
The discovery of a transient kilonova following the gravitational-wave (GW) event GW170817 highlighted the critical need for coordinated rapid and wide-field observations, inference, and follow-up across the electromagnetic spectrum. In the southern hemisphere, the Dark Energy Camera (DECam) on the Blanco 4 m telescope is well suited to this task,…
Expanding the Sample of Radio Minihalos in Galaxy Clusters
Clarke, Tracy E.; Giacintucci, Simona; Venturi, Tiziana +4 more
Radio minihalos are diffuse synchrotron sources of unknown origin found in the cool cores of some galaxy clusters. We use GMRT and VLA data to expand the sample of minihalos by reporting three new minihalo detections (A2667, A907, and PSZ1 G139.61+24.20) and confirming minihalos in five clusters (MACS J0159.8-0849, MACS J0329.6-0211, RXC J2129.6+0…
The Molecular Gas Reservoirs of z ∼ 2 Galaxies: A Comparison of CO(1-0) and Dust-based Molecular Gas Masses
Walter, F.; Scoville, N.; Riechers, D. A. +7 more
We test the use of long-wavelength dust continuum emission as a molecular gas tracer at high redshift, via a unique sample of a dozen z ∼ 2 galaxies with observations of both the dust continuum and CO(1-0) line emission (obtained with the Atacama Large Millimeter Array and Karl G. Jansky Very Large Array, respectively). Our work is motivated by re…
Why Do Torus-unstable Solar Filaments Experience Failed Eruptions?
Wang, Yuming; Zhuang, Bin; Liu, Lijuan +5 more
We study the magnetic field and 3D configuration of 16 filament eruptions during 2010 July-2013 February in order to investigate the factors that control the success and/or failure of solar eruptions. All of these events, i.e., eruptions that failed to be ejected and become coronal mass ejections, have filament maximum heights exceeding 100 Mm. Th…
A Family Picture: Tracing the Dynamical Path of the Structural Properties of Multiple Populations in Globular Clusters
Dalessandro, Emanuele; Martocchia, S.; Bastian, N. +6 more
We studied the spatial distributions of multiple stellar populations (MPs) in a sample of 20 globular clusters (GCs) spanning a broad range of dynamical ages. The differences between first-population (FP) and second-population (SP) stars were measured by means of the parameter A +, defined as the area enclosed between their cumulative r…
First Detection of Plasmoids from Breakout Reconnection on the Sun
Antiochos, Spiro K.; Kumar, Pankaj; DeVore, C. Richard +2 more
Transient collimated plasma ejections (jets) occur frequently throughout the solar corona, in active regions, quiet Sun, and coronal holes. Although magnetic reconnection is generally agreed to be the mechanism of energy release in jets, the factors that dictate the location and rate of reconnection remain unclear. Our previous studies demonstrate…
A Precision Measurement of the Mass of the Black Hole in NGC 3258 from High-resolution ALMA Observations of Its Circumnuclear Disk
Ho, Luis C.; Barth, Aaron J.; Buote, David A. +4 more
We present ∼0.″10 resolution Atacama Large Millimeter/submillimeter Array (ALMA) CO(2-1) imaging of the arcsecond-scale (r ≈ 150 pc) dusty molecular disk in the giant elliptical galaxy NGC 3258. The data provide unprecedented resolution of the cold gas disk kinematics within the dynamical sphere of influence of a supermassive black hole (BH), reve…
The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XVIII. Proper-motion Kinematics of Multiple Stellar Populations in the Core Regions of NGC 6352
Vesperini, Enrico; Anderson, Jay; van der Marel, Roeland P. +5 more
We present the analysis of the radial distributions and kinematic properties of the multiple stellar populations (mPOPs) hosted in the globular cluster (GC) NGC 6352 as part of the Hubble Space Telescope “UV Legacy Survey of Galactic Globular Clusters” program. NGC 6352 is one of the few GCs for which the mPOP tagging in appropriate color-magnitud…
The Mass Inflow and Outflow Rates of the Milky Way
Richter, Philipp; Heckman, Timothy M.; Fox, Andrew J. +5 more
We present new calculations of the mass inflow and outflow rates around the Milky Way (MW), derived from a catalog of ultraviolet metal-line high-velocity clouds (HVCs). These calculations are conducted by transforming the HVC velocities into the Galactic standard of rest (GSR) reference frame, identifying inflowing (v GSR < 0 km s