Search Publications
A Fully Kinetic Perspective of Electron Acceleration around a Weakly Outgassing Comet
Henri, Pierre; Lapenta, Giovanni; Divin, Andrey +4 more
The cometary mission Rosetta has shown the presence of higher-than-expected suprathermal electron fluxes. In this study, using 3D fully kinetic electromagnetic simulations of the interaction of the solar wind with a comet, we constrain the kinetic mechanism that is responsible for the bulk electron energization that creates the suprathermal distri…
The Origin of a Distributed Stellar Population in the Star-forming Region W4
Lim, Beomdu; Lee, Jeong-Eun; Yun, Hyeong-Sik +5 more
Stellar kinematics provides the key to understanding the formation process and dynamical evolution of stellar systems. Here, we present a kinematic study of the massive star-forming region (SFR) W4 in the Cassiopeia OB6 association using the Gaia Data Release 2 and high-resolution optical spectra. This SFR is composed of a core cluster (IC 1805) a…
2003-2019 Monitoring of the Crab Emission through INTEGRAL SPI, or Vice Versa
Jourdain, E.; Roques, J. P.
The Crab Nebula is used by many instruments as a calibration source, in particular at high energy, where it is one of the brightest celestial objects. The spectrometer INTEGRAL SPI (20 keV-8 MeV), in operation since 2002 October, offers a large data set dedicated to this source, with regular campaigns planned twice per year. We have analyzed the a…
The Not So Simple Stellar System ω Cen. II. Evidence in Support of a Merging Scenario
Rest, Armin; Mastrobuono-Battisti, Alessandra; Zenteno, Alfredo +7 more
We present multiband photometry covering ∼5° × 5° across ω Cen collected with the Dark Energy Camera on the 4 m Blanco telescope, combined with Hubble Space Telescope and Wide Field Imager data for the central regions. The unprecedented photometric accuracy and field coverage allows us to confirm the different spatial distribution of blue and red …
When Does the Onset of Multiple Stellar Populations in Star Clusters Occur? III. No Evidence of Significant Chemical Variations in Main-sequence Stars of NGC 419
Milone, Antonino P.; Li, Chengyuan; Ji, Xin +3 more
Recent studies have revealed that the onset age for the presence of multiple stellar populations (MPs) in star clusters seems to correspond to the disappearance of the extended main-sequence turnoff in young clusters, a pattern associated with stellar rotations. A speculative suggestion is that MPs might be caused by the magnetic brake, a stellar …
Rotation of Solar Analogs Crossmatching Kepler and Gaia DR2
Barnes, S. A.; Castro, M.; da Costa, J. S. +10 more
A major obstacle to interpreting the rotation period distribution for main-sequence stars from Kepler mission data has been the lack of a precise evolutionary status for these objects. We address this by investigating the evolutionary status based on Gaia Data Release 2 parallaxes and photometry for more than 30,000 Kepler stars with rotation peri…
A Tale of Two Transition Disks: ALMA Long-baseline Observations of ISO-Oph 2 Reveal Two Closely Packed Nonaxisymmetric Rings and a ∼2 au Cavity
Flock, Mario; Herczeg, Gregory J.; Pinilla, Paola +12 more
ISO-Oph 2 is a wide-separation (240 au) binary system where the primary star harbors a massive (Mdust ∼ 40 M⊕) ring-like disk with a dust cavity ∼50 au in radius and the secondary hosts a much lighter (Mdust ∼ 0.8 M⊕) disk. As part of the high-resolution follow-up of the "Ophiuchus Disk Survey Employing …
Molecular Gas Outflow in the Starburst Galaxy NGC 1482
Salak, Dragan; Nakai, Naomasa; Miyamoto, Yusuke +1 more
Galactic winds are essential to the regulation of star formation in galaxies. To study the distribution and dynamics of molecular gas in wind, we imaged the nearby starburst galaxy NGC 1482 in CO (J = 1 → 0) at a resolution of 1″ (≈100 pc) using the Atacama Large Millimeter/submillimeter Array. Molecular gas is detected in a nearly edge-on disk wi…
Characterizing the Circumgalactic Medium of the Lowest-mass Galaxies: A Case Study of IC 1613
Putman, Mary E.; Kirby, Evan N.; Werk, Jessica K. +3 more
Using 10 sight lines observed with the Hubble Space Telescope/Cosmic Origins Spectrograph, we study the circumgalactic medium (CGM) and outflows of IC 1613, which is a low-mass (M* ∼ 108 M⊙), dwarf irregular galaxy on the outskirts of the Local Group. Among the sight lines, four are pointed toward UV-bright stars i…
Confirmation of Enhanced Long-wavelength Dust Emission in OMC 2/3
Friesen, Rachel; Sadavoy, Sarah; Mroczkowski, Tony +8 more
Previous continuum observations from the MUSTANG camera on the Green Bank Telescope (GBT) of the nearby star-forming filament OMC 2/3 found elevated emission at 3.3 mm relative to shorter-wavelength data. As a consequence, the inferred dust emissivity index obtained from modified blackbody dust spectra was considerably lower than what is typically…