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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…
X-Ray Emission from the PeVatron-candidate Supernova Remnant G106.3+2.7
Matsumoto, Hironori; Bamba, Aya; Fujita, Yutaka +1 more
We report the discovery of diffuse X-ray emission around the supernova remnant (SNR) G106.3+2.7, which is associated with VER J2227+608 and HAWC J2227+610 and is known as a candidate for a PeV cosmic-ray accelerator (PeVatron). We analyze observational data of Suzaku around the SNR and the adjacent pulsar PSR J2229+6114. We find diffuse X-ray emis…
On the Co-orbitation of Satellite Galaxies along the Great Plane of Andromeda: NGC 147, NGC 185, and Expectations from Cosmological Simulations
Pawlowski, Marcel S.; Tony Sohn, Sangmo
Half of the satellite galaxies of Andromeda form a narrow plane termed the Great Plane of Andromeda (GPoA), and their line-of-sight velocities display a correlation reminiscent of a rotating structure. Recently reported first proper-motion measurements for the on-plane satellites NGC 147 and NGC 185 indicate that they indeed co-orbit along the GPo…
The Dusty Heart of NGC 4151 Revealed by λ ∼ 1-40 µm Reverberation Mapping and Variability: A Challenge to Current Clumpy Torus Models
Lyu, Jianwei; Rieke, George H.
We probe the dusty environment of the archetypical Type 1 active galactic nucleus (AGN) in NGC 4151 with comprehensive IR reverberation mapping over several decades, in the J (∼1.22 µm), H (∼1.63 µm), K (∼2.19 µm), L (∼3.45 µm), and N bands (∼10.6 µm), plus multiple measurements at 20-40 µm. At 1-4 µm, the…
Orbital Torus Imaging: Using Element Abundances to Map Orbits and Mass in the Milky Way
Brownstein, Joel R.; Hogg, David W.; Rix, Hans-Walter +11 more
Many approaches to galaxy dynamics assume that the gravitational potential is simple and the distribution function is time invariant. Under these assumptions there are traditional tools for inferring potential parameters given observations of stellar kinematics (e.g., Jeans models). However, spectroscopic surveys measure many stellar properties be…