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4FGL J1120.0-2204: A Unique Gamma-Ray-bright Neutron Star Binary with an Extremely Low-mass Proto-white Dwarf
Strader, Jay; Dage, Kristen C.; Chomiuk, Laura +5 more
We have discovered a new X-ray-emitting compact binary that is the likely counterpart to the unassociated Fermi-LAT GeV γ-ray source 4FGL J1120.0-2204, the second brightest Fermi source that still remains formally unidentified. Using optical spectroscopy with the SOAR telescope, we have identified a warm (T eff ~ 8500 K) companion in a …
High-energy Emission Component, Population, and Contribution to the Extragalactic Gamma-Ray Background of Gamma-Ray-emitting Radio Galaxies
Fukazawa, Yasushi; Inoue, Yoshiyuki; Matake, Hiroto +2 more
In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 Fermi Large Area Telescope detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy spectral component of radio galaxies, similar to blazars. With this sample, we also constructed a gamma-ray luminosity functi…
Spinning up the Surface: Evidence for Planetary Engulfment or Unexpected Angular Momentum Transport?
Reffert, Sabine; García, Rafael A.; Breton, Sylvain N. +15 more
In this paper, we report the potential detection of a nonmonotonic radial rotation profile in a low-mass lower-luminosity giant star. For most low- and intermediate-mass stars, the rotation on the main sequence seems to be close to rigid. As these stars evolve into giants, the core contracts and the envelope expands, which should suggest a radial …
Revealing the Nature of a Lyα Halo in a Strongly Lensed Interacting System at z = 2.92
Rigby, Jane R.; Sharon, Keren; Infante, Leopoldo +12 more
Spatially extended halos of H I Lyα emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative transfer effects of the Lyα line and limited angular resolution. In this paper, we present resolved Multi Unit Spec…
Two Candidate KH 15D-like Systems from the Zwicky Transient Facility
Fang, Min; Zang, Weicheng; Dong, Subo +8 more
KH 15D contains a circumbinary disk that is tilted relative to the orbital plane of the central binary. The precession of the disk and the orbital motion of the binary together produce rich phenomena in the photometric light curve. In this work, we present the discovery and preliminary analysis of two objects that resemble the key features of KH 1…
The Rapidly Evolving Asymptotic Giant Branch Star, V Hya: ALMA Finds a Multiring Circus with High-velocity Outflows
Sahai, R.; Morris, M. R.; Lee, C. -F. +3 more
We have observed the mass-losing carbon star V Hya that is apparently transitioning from an asymptotic giant branch star to a bipolar planetary nebula, at an unprecedented angular resolution of ~0.″4-0.″6 with the Atacama Large Millimeter/submillimeter Array. Our 13CO and 12CO (J = 3-2 and J = 2-1) images have led to the disc…
ALMA Detections of [O III] and [C II] Emission Lines From A1689-zD1 at z = 7.13
Hashimoto, Tetsuya; Goto, Tomotsugu; Kim, Seong Jin +10 more
A1689-zD1 is one of the most distant galaxies, discovered with the aid of gravitational lensing, providing us with an important opportunity to study galaxy formation in the very early universe. In this study, we report the detection of [C II]158 µm and [O III]88 µm emission lines of A1689-zD1 in the Atacama Large Millimeter/submillimet…
The Rotation of Magnetic Flux Ropes Formed during Solar Eruption
Wang, Yuming; Liu, Rui; Jiang, Chaowei +3 more
Eruptions of solar filaments often show rotational motion about their rising direction, but the mechanism governing such rotation, and how the rotation is related to the initial morphology of the preeruptive filament (and cospatial sigmoid), filament chirality, and magnetic helicity, remains elusive. The conventional view of rotation as a result o…
Modeling the Transport of Relativistic Solar Protons along a Heliospheric Current Sheet during Historic GLE Events
Laitinen, Timo; Dalla, Silvia; Waterfall, Charlotte O. G. +2 more
There are many difficulties associated with forecasting high-energy solar particle events at Earth. One issue is understanding why some large solar eruptive events trigger ground-level enhancement (GLE) events and others do not. In this work we perform 3D test particle simulations of a set of historic GLEs to understand more about what causes thes…
PHANGS-JWST First Results: Spurring on Star Formation: JWST Reveals Localized Star Formation in a Spiral Arm Spur of NGC 628
Sandstrom, Karin M.; Henshaw, Jonathan D.; Kruijssen, J. M. Diederik +34 more
We combine JWST observations with Atacama Large Millimeter/submillimeter Array CO and Very Large Telescope MUSE Hα data to examine off-spiral arm star formation in the face-on, grand-design spiral galaxy NGC 628. We focus on the northern spiral arm, around a galactocentric radius of 3-4 kpc, and study two spurs. These form an interesting contrast,…