Search Publications
ALMA Observations of the Solar Chromosphere on the Polar Limb
Shimojo, Masumi; Okamoto, Takenori J.; Yokoyama, Takaaki +1 more
We report the results of the Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of the solar chromosphere on the southern polar limb. Coordinated observations with the Interface Region Imaging Spectrograph (IRIS) are also conducted. ALMA provided unprecedented high spatial resolution in the millimeter band (≈2.″0) at 100 GHz frequen…
Dense Molecular Gas in the Starburst Nucleus of NGC 1808
Salak, Dragan; Tomiyasu, Yuto; Nakai, Naomasa +3 more
Dense molecular gas tracers in the central 1 kpc region of the superwind galaxy NGC 1808 have been imaged by ALMA at a resolution of 1″ (∼50 pc). Integrated intensities and line intensity ratios of HCN (1-0), H13CN (1-0), HCO+ (1-0), H13CO+ (1-0), HOC+ (1-0), HCO+ (4-3), CS (2-1), C…
Wide-field Optical Spectroscopy of Abell 133: A Search for Filaments Reported in X-Ray Observations
Kelson, Daniel D.; Patel, Shannon G.; Connor, Thomas +7 more
Filaments of the cosmic web have long been associated with the threadlike structures seen in galaxy redshift surveys. However, despite their baryon content being dominated by hot gas, these filaments have been an elusive target for X-ray observations. Recently, detections of filaments in very deep (2.4 Ms) observations with Chandra were reported a…
The First Continuous Optical Monitoring of the Transitional Millisecond Pulsar PSR J1023+0038 with Kepler
D'Avanzo, P.; Campana, S.; Stella, L. +10 more
We report on the first continuous, 80-day optical monitoring of the transitional millisecond pulsar PSR J1023+0038 carried out in mid 2017 with Kepler in the K2 configuration, when an X-ray subluminous accretion disk was present in the binary. Flares lasting from minutes to 14 hr were observed for 15.6% of the time, which is a larger fraction than…
Star Formation in the Sh 2-53 Region Influenced by Accreting Molecular Filaments
Tamura, M.; Tachihara, Kengo; Dewangan, L. K. +6 more
We present a multiwavelength analysis of a ∼30‧ × 30‧ area around the Sh 2-53 region (hereafter S53 complex), which is associated with at least three H II regions, two mid-infrared bubbles (N21 and N22), and infrared dark clouds. The 13CO line data trace the molecular content of the S53 complex in a velocity range of 36-60 km s-1
Investigating the Structure of Vela X
Chevalier, R. A.; Miceli, M.; Bocchino, F. +9 more
Vela X is a prototypical example of a pulsar wind nebula whose morphology and detailed structure have been affected by interaction with the reverse shock of its host supernova remnant. The resulting complex of filamentary structure and mixed-in ejecta embedded in a nebula that is offset from the pulsar provides the best example we have of this mid…
Eclipsing Binaries in the Open Cluster Ruprecht 147. I. EPIC 219394517
Torres, Guillermo; Vanderburg, Andrew; Kraus, Adam L. +2 more
Eclipsing binaries in star clusters offer more stringent tests of stellar evolution theory than field binaries because models must not only match the binary properties, but also the radiative properties of all other cluster members at a single chemical composition and a single age. Here we report new spectroscopic observations of the G-type, detac…
On the Kinematic Signature of the Galactic Warp As Revealed By the LAMOST-TGAS Data
Huang, Y.; Chen, B. -Q.; Wang, C. +6 more
Using a sample of about 123,000 stars with accurate 3D velocity measurements from the LAMOST-TGAS data, we confirm the kinematic signature of the Galactic warp recently found by Schönrich & Dehnen. The data reveal a clear trend of increasing mean vertical velocity \overline{{V}z} as a function of absolute vertical angular momentum L…
Two-sided-loop Jets Associated with Magnetic Reconnection between Emerging Loops and Twisted Filament Threads
Chen, Yao; Huang, Zhenghua; Zheng, Ruisheng +3 more
Coronal jets are always produced by magnetic reconnection between emerging flux and pre-existing overlying magnetic fields. When the overlying field is vertical/oblique or horizontal, the coronal jet will appear as anemone type or two-sided-loop type. Most observational jets are of the anemone type, and only a few two-sided-loop jets have been rep…
The Minimum Mass of Rotating Main-sequence Stars and its Impact on the Nature of Extended Main-sequence Turnoffs in Intermediate-age Star Clusters in the Magellanic Clouds
Girardi, Léo; Bellini, Andrea; Goudfrooij, Paul +3 more
Extended main-sequence turnoffs (eMSTOs) are a common feature in color-magnitude diagrams (CMDs) of young and intermediate-age star clusters in the Magellanic Clouds. The nature of eMSTOs is still debated. The most popular scenarios are extended star formation and ranges of stellar rotation rates. Here, we study implications of a kink feature in t…