Search Publications
Type Ibn Supernovae May not all Come from Massive Stars
Zabludoff, Ann I.; French, K. Decker; Berger, Edo +5 more
Because core-collapse supernovae are the explosions of massive stars, which have relatively short lifetimes, they occur almost exclusively in galaxies with active star formation. On the other hand, the Type Ibn supernova PS1-12sk exploded in an environment that is much more typical of thermonuclear (Type Ia) supernovae: on the outskirts of the bri…
Interstellar Neutral Gas Species and Their Pickup Ions inside the Heliospheric Termination Shock. Ionization Rates for H, O, Ne, and He
Tokumaru, Munetoshi; Bzowski, Maciej; Sokół, Justyna M.
Solar ionizing factors are responsible for modulation of interstellar neutral gas and its derivative populations inside the heliosphere. We provide an overview of the current state of knowledge about them for heliospheric particles inside the termination shock. We discuss charge exchange with solar wind particles, photoionization, and electron imp…
Characterization of Ring Substructures in the Protoplanetary Disk of HD 169142 from Multiwavelength Atacama Large Millimeter/submillimeter Array Observations
Flock, Mario; Henning, Thomas; Dent, William R. F. +10 more
We present a detailed multiwavelength characterization of the multi-ring disk of HD 169142. We report new Atacama Large Millimeter/submillimeter Array (ALMA) observations at 3 mm and analyze them together with archival 0.89 and 1.3 mm data. Our observations resolve three out of the four rings in the disk previously seen in high-resolution ALMA dat…
Understanding the Limitations of Gyrochronology for Old Field Stars
Metcalfe, Travis S.; Egeland, Ricky
Nearly half a century has passed since the initial indications that stellar rotation slows while chromospheric activity weakens with a power-law dependence on age, the so-called Skumanich relations. Subsequent characterization of the mass-dependence of this behavior up to the age of the Sun led to the advent of gyrochronology, which uses the rotat…
Multiple Temperature Components of the Hot Circumgalactic Medium of the Milky Way
Nicastro, Fabrizio; Mathur, Smita; Gupta, Anjali +2 more
We present a deep XMM-Newton observation of the Galactic halo emission in the direction of the blazar 1ES 1553+113. In order to extract the Galactic halo component from the diffuse soft X-ray emission spectrum, accurately modeling the foreground components is crucial. Here we present complex modeling of the foregrounds with unprecedented details. …
Multiple Components of the Jhelum Stellar Stream
Conroy, Charlie; Hogg, David W.; Price-Whelan, Adrian M. +1 more
In simple models of the Milky Way, tidally disrupting satellites produce long and thin—nearly one-dimensional—stellar streams. Using astrometric data from the Gaia second data release and photometry from the Dark Energy Survey, we demonstrate that the Jhelum stream, a stellar stream in the inner halo, is a two-dimensional structure. The spatial di…
Star Formation and ISM Properties in the Host Galaxies of Three Far-infrared Luminous Quasars at z ∼ 6
Strauss, Michael A.; Fan, Xiaohui; Jiang, Linhua +11 more
We present Karl G. Jansky Very Large Array observations of the CO (2-1) line emission toward three far-infrared luminous quasars at z ∼ 6: SDSS J231038.88+185519.7 and SDSS J012958.51-003539.7 with ∼0.″6 resolution and SDSS J205406.42-000514.8 with ∼2.″1 resolution. All three sources are detected in the CO (2-1) line emission—one source is margina…
Imaging the Thermal and Kinematic Sunyaev-Zel'dovich Effect Signals in a Sample of 10 Massive Galaxy Clusters: Constraints on Internal Velocity Structures and Bulk Velocities
Mroczkowski, Tony; Cibirka, Nathália; Zitrin, Adi +10 more
We have imaged the Sunyaev-Zel'dovich (SZ) effect signals at 140 and 270 GHz toward 10 galaxy clusters with Bolocam and AzTEC/ASTE. We also used Planck data to constrain the signal at large angular scales, Herschel-SPIRE images to subtract the brightest galaxies that comprise the cosmic infrared background (CIB), Chandra imaging to map the electro…
Stellar Rotation and the Extended Main-sequence Turnoff in the Open Cluster NGC 5822
Albrow, Michael D.; Deng, Licai; de Grijs, Richard +1 more
The origin of extended main-sequence turnoffs (eMSTOs) in intermediate-age (1-3 Gyr) clusters is one of the most intriguing questions in current star cluster research. Unlike the split main sequences found in some globular clusters, which are caused by bimodal populations in age and/or chemical abundances, eMSTOs are believed to be due to stellar …
Identifying Sagittarius Stream Stars by Their APOGEE Chemical Abundance Signatures
Bizyaev, Dmitry; Pan, Kaike; Cunha, Katia +17 more
The SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey provides precise chemical abundances of 18 chemical elements for ∼176,000 red giant stars distributed over much of the Milky Way Galaxy (MW), and includes observations of the core of the Sagittarius dwarf spheroidal galaxy (Sgr). The APOGEE chemical abundance patter…