Search Publications
The Formation Height of Millimeter-wavelength Emission in the Solar Chromosphere
Martínez-Sykora, Juan; De Pontieu, Bart; Chintzoglou, Georgios +1 more
In the past few years, the ALMA radio telescope has become available for solar observations. ALMA diagnostics of the solar atmosphere are of high interest because of the theoretically expected linear relationship between the brightness temperature at millimeter wavelengths and the local gas temperature in the solar atmosphere. Key for the interpre…
The PIPER Survey. I. An Initial Look at the Intergalactic Globular Cluster Population in the Perseus Cluster
Wittmann, Carolin; Lisker, Thorsten; Romanowsky, Aaron J. +7 more
We describe the goals and first results of the Program for Imaging of the PERseus cluster of galaxies (PIPER). The first phase of the program builds on imaging of fields obtained with the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS)/WFC and WFC3/UVIS cameras. Our PIPER target fields with HST include major early-type galaxies incl…
WISEA J083011.95+283716.0: A Missing Link Planetary-mass Object
Wisniewski, John; Kirkpatrick, J. Davy; Burgasser, Adam J. +17 more
We present the discovery of WISEA J083011.95+283716.0, the first Y-dwarf candidate identified through the "Backyard Worlds: Planet 9" citizen science project. We identified this object as a red, fast-moving source with a faint W2 detection in multiepoch AllWISE and unWISE images. We have characterized this object with Spitzer and Hubble Space Tele…
ALMA CO Observations of Gamma-Ray Supernova Remnant N132D in the Large Magellanic Cloud: Possible Evidence for Shocked Molecular Clouds Illuminated by Cosmic-Ray Protons
Filipović, M. D.; Vink, J.; Rowell, G. +23 more
N132D is the brightest gamma-ray supernova remnant (SNR) in the Large Magellanic Cloud (LMC). We carried out 12CO(J = 1-0, 3-2) observations toward the SNR using the Atacama Large Millimeter/submillimeter Array (ALMA) and Atacama Submillimeter Telescope Experiment. We find diffuse CO emission not only at the southern edge of the SNR as …
SCExAO/CHARIS High-contrast Imaging of Spirals and Darkening Features in the HD 34700 A Protoplanetary Disk
Currie, Thayne; Kwon, Jungmi; Tamura, Motohide +27 more
We present Subaru/SCExAO+Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS) broadband (JHK-band) integral field spectroscopy of HD 34700 A. CHARIS data recover HD 34700 A's disk ring and confirm multiple spirals discovered by Monnier et al. We set limits on substellar companions of ∼12 MJup at 0"3 (in the ring gap) and …
Supernova Interaction with a Dense Detached Shell in SN 2001em
Chandra, Poonam; Fransson, Claes; Chevalier, Roger A. +2 more
We carry out a comprehensive analysis of supernova SN 2001em covering a period of 19 yr since discovery. SN 2001em is the oldest supernova known to have undergone a metamorphosis from a stripped envelope to an interacting supernova. An early spectrum indicates it exploded as a Type Ib supernova. Later, the ejecta caught up with a dense circumstell…
PSR J1641+3627F: A Low-mass He White Dwarf Orbiting a Possible High-mass Neutron Star in the Globular Cluster M13
Cadelano, Mario; Pallanca, Cristina; Salaris, Maurizio +5 more
We report on the discovery of the companion star to the millisecond pulsar J1631+3627F in the globular cluster M13. By means of a combination of optical and near-UV high-resolution observations obtained with the Hubble Space Telescope, we identified the counterpart at the radio source position. Its location in the color-magnitude diagrams reveals …
Cometary Activity Discovered on a Distant Centaur: A Nonaqueous Sublimation Mechanism
Chandler, Colin Orion; Trujillo, Chadwick A.; Oldroyd, William J. +2 more
Centaurs are minor planets thought to have originated in the outer solar system region known as the Kuiper Belt. Active Centaurs enigmatically display comet-like features (e.g., tails, comae) even though they orbit in the gas giant region where it is too cold for water to readily sublimate. Only 18 active Centaurs have been identified since 1927 a…
The State of the Heliosphere Revealed by Limb-halo Coronal Mass Ejections in Solar Cycles 23 and 24
Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji
We compare the properties of halo coronal mass ejections (CMEs) that originate close to the limb (within a central meridian distance range of 60°-∼90°) during solar cycles 23 and 24 to quantify the effect of the heliospheric state on CME properties. There are 44 and 38 limb halos in cycles 23 and 24, respectively. Normalized to the cycle-averaged …
Cool, Luminous, and Highly Variable Stars in the Magellanic Clouds from ASAS-SN: Implications for Thorne-Żytkow Objects and Super-asymptotic Giant Branch Stars
Drout, Maria R.; O'Grady, Anna J. G.; Kochanek, C. S. +9 more
Stars with unusual properties can provide a wealth of information about rare stages of stellar evolution and exotic physics. However, determining the true nature of peculiar stars is often difficult. In this work, we conduct a systematic search for cool and luminous stars in the Magellanic Clouds with extreme variability, motivated by the properti…