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Identifying the Coronal Source Regions of Solar Wind Streams from Total Solar Eclipse Observations and in situ Measurements Extending over a Solar Cycle
Johnson, Judd; Habbal, Shadia R.; Druckmüller, Miloslav +7 more
This letter capitalizes on a unique set of total solar eclipse observations acquired between 2006 and 2020 in white light, Fe XI 789.2 nm (Tfexi = 1.2 ± 0.1 MK), and Fe XIV 530.3 nm (Tfexiv = 1.8 ± 0.1 MK) emission complemented by in situ Fe charge state and proton speed measurements from Advanced Composition Explorer/SWEPAM-…
Detection of Flare-associated CME Candidates on Two M-dwarfs by GWAC and Fast, Time-resolved Spectroscopic Follow-ups
Wang, J.; Li, H. L.; Xin, L. P. +8 more
The flare-associated stellar coronal mass ejections (CMEs) of solar-like and late-type stars profoundly impact the habitability of any expolanets in the systems. In this paper, we report the detection of flare-associated CMEs for two M-dwarfs, thanks to a high-cadence survey carried out by the Ground Wide-angle Camera system and fast photometric a…
Resolving Structure in the Debris Disk around HD 206893 with ALMA
Hughes, A. Meredith; Wilner, David J.; Moór, Attila +7 more
Debris disks are tenuous, dusty belts surrounding main-sequence stars generated by collisions between planetesimals. HD 206893 is one of only two stars known to host a directly imaged brown dwarf orbiting interior to its debris ring, in this case at a projected separation of 10.4 au. Here we resolve structure in the debris disk around HD 206893 at…
Multi-wavelength Observations of AT2019wey: a New Candidate Black Hole Low-mass X-ray Binary
Kulkarni, S. R.; Cenko, S. Bradley; Duev, Dmitry A. +21 more
AT2019wey (SRGA J043520.9+552226, SRGE J043523.3+552234) is a transient first reported by the ATLAS optical survey in 2019 December. It rose to prominence upon detection, three months later, by the Spektrum-Roentgen-Gamma (SRG) mission in its first all-sky survey. X-ray observations reported in Yao et al. suggest that AT2019wey is a Galactic low-m…
Rotating Filament in Orion B: Do Cores Inherit Their Angular Momentum from Their Parent Filament?
Mardones, Diego; Hsieh, Cheng-Han; Arce, Héctor G. +2 more
Angular momentum is one of the most important physical quantities that governs star formation. The initial angular momentum of a core may be responsible for its fragmentation, and can have an influence on the size of the protoplanetary disk. To understand how cores obtain their initial angular momentum, it is important to study the angular momentu…
A Chandra and HST View of WISE-selected AGN Candidates in Dwarf Galaxies
Greene, Jenny E.; Hainline, Kevin N.; Stern, Daniel +2 more
Reliably identifying active galactic nuclei (AGNs) in dwarf galaxies is key to understanding black hole (BH) demographics at low masses and constraining models for BH seed formation. Here we present Chandra X-ray Observatory observations of 11 dwarf galaxies that were chosen as AGN candidates using Wide-field Infrared Survey Explorer (WISE) mid-in…
Dissecting the Supercritical Filaments Embedded in the 0.5 pc Subsonic Region of Barnard 5
Caselli, Paola; Pineda, Jaime E.; Arce, Héctor G. +7 more
We characterize in detail the two ∼0.3 pc long filamentary structures found within the subsonic region of Barnard 5. We use combined Robert C. Byrd Green Bank Telescope and Very Large Array observations of the molecular lines NH3(1,1) and (2,2) at a resolution of 1800 au, as well as James Clerk Maxwell Telescope continuum observations a…
The Photospheric Footpoints of Solar Coronal Hole Jets
Muglach, K.
We study the photospheric footpoints of a set of 35 coronal jets in a coronal hole as observed by Hinode/EIS. We use SDO/AIA data to coalign the spectroscopic EIS data with SDO/HMI line-of-sight magnetograms and calculate the plane-of-sky flow field using local correlation tracking (LCT) on SDO/HMI white light images. The jets are put into categor…
Cosmic Evolution of Barred Galaxies up to z 0.84
Park, Myeong-Gu; Ann, Hong Bae; Sheth, Kartik +4 more
We explore the cosmic evolution of the bar length, strength, and light deficit around the bar for 379 barred galaxies at 0.2 < z ≤ 0.835 using F814W images from the COSMOS survey. Our sample covers galaxies with stellar masses $10.0\leqslant \mathrm{log}({M}_{* }/{M}_{\odot })\leqslant 11.4$ and various Hubble types. The bar length is strongly …
Discovery of a New Redback Millisecond Pulsar Candidate: 4FGL J0940.3-7610
Strader, Jay; Dage, Kristen C.; Chomiuk, Laura +3 more
We have discovered a new candidate redback millisecond pulsar binary near the center of the error ellipse of the bright unassociated Fermi-LAT γ-ray source 4FGL J0940.3-7610. The candidate counterpart is a variable optical source that also shows faint X-ray emission. Optical photometric and spectroscopic monitoring with the SOAR telescope indicate…