Search Publications
Compound Eruptions of Twin Flux Ropes in a Solar Active Region
Zhang, Liang; Chen, Yao; Feng, Shiwei +6 more
Compound eruptions represent that multiple closely spaced magnetic structures erupt consecutively within a short interval, and then lead to a single flare and a single coronal mass ejection (CME). However, it is still subtle for the links between multiple eruptions and the associated single flare or/and single CME. In this Letter, we report the co…
The z 2 [O III] Luminosity Function of Grism-selected Emission-line Galaxies
Schneider, Donald P.; Gronwall, Caryl; Ciardullo, Robin +7 more
Upcoming missions such as Euclid and the Nancy Grace Roman Space Telescope (Roman) will use emission-line-selected galaxies to address a variety of questions in cosmology and galaxy evolution in the z > 1 universe. The optimal observing strategy for these programs relies on knowing the number of galaxies that will be found and the bias of the g…
The Spatial Distributions of Blue Main-sequence Stars in Magellanic Cloud Star Clusters
Deng, Licai; de Grijs, Richard; Li, Chengyuan +1 more
The color-magnitude diagrams of young star clusters show that, particularly at ultraviolet wavelengths, their upper main sequences (MSs) bifurcate into a sequence comprising the bulk population and a blue periphery. The spatial distribution of stars is crucial to understanding the reasons for these distinct stellar populations. This study uses hig…
The Astrophysical Variance in Gaia-Radial Velocity Spectrometer Spectra
Rampalli, Rayna; Ness, Melissa; Wylie, Shola
Large surveys are providing a diversity of spectroscopic observations with Gaia alone set to deliver millions of Ca-triplet-region spectra across the Galaxy. We aim to understand the dimensionality of the chemical abundance information in the Gaia-Radial Velocity Spectrometer (RVS) data to inform galactic archeology pursuits. We fit a quadratic mo…
Successive Coronal Mass Ejections Associated with Weak Solar Energetic Particle Events
Lugaz, Noé; Zhuang, Bin; Gou, Tingyu +1 more
The scenario of twin coronal mass ejections (CMEs), i.e., a fast and wide primary CME (priCME) preceded by preceding CMEs (preCMEs), has been found to be favorable to a more efficient particle acceleration in large solar energetic particle (SEP) events. Here we study 19 events during 2007-2014 associated with twin-CME eruptions but without large S…
Revealing Ionization Conditions of Sz 102 with Spatially Resolved [Ne III] Microjets
Herczeg, Gregory J.; Liu, Chun-Fan; Shang, Hsien +1 more
Forbidden neon emission lines from small-scale microjets can probe high-energy processes in low-mass young stellar systems. We obtained spatially resolved [Ne III] spectra in the microjets from the classical T Tauri Star Sz 102 using the Hubble Space Telescope Imaging Spectrograph at a spatial resolution of ∼0"1. The blueshifted and redshifted [Ne…
The G 305 Star-forming Region. II. Irregular Variable Stars
Bayo, A.; Kounkel, Marina; Minniti, Dante +11 more
We present a catalog of 167 newly discovered, irregular variables spanning a ~7 deg2 area that encompasses the G 305 star-forming complex, one of the most luminous giant H II regions in the Galaxy. We aim to unveil and characterize the young stellar object (YSO) population of the region by analyzing the Ks-band variability an…
Planck Galactic Cold Clumps at High Galactic Latitude-a Study with CO Lines
Kim, Gwanjeong; Lee, Chin-Fei; Lee, Jeong-Eun +28 more
Gas at high Galactic latitude is a relatively little noticed component of the interstellar medium. In an effort to address this, 41 Planck Galactic Cold Clumps at high Galactic latitude (HGal; ∣b∣ > 25°) were observed in 12CO, 13CO, and C18O J = 1-0 lines, using the Purple Mountain Observatory 13.7 m telescope. …
In the Trenches of the Solar-stellar Connection. V. High-resolution Ultraviolet and X-Ray Observations of Sun-like Stars: The Curious Case of Procyon
Ayres, Thomas R.
A joint X-ray (0.2-2 keV) and ultraviolet (1150-3000 Å) time-domain study has been carried out on three nearby bright late-type stars, bracketing the Sun in properties. Alpha Cen A (HD 128620: G2 V) is a near twin to the Sun, although slightly more massive and luminous, slightly metal-rich, but older. Alpha Cen B (HD 128621: K1 V) is cooler than t…
Saddle-shaped Solar Flare Arcades
Aulanier, Guillaume; Dudík, Jaroslav; Lörinčík, Juraj
Arcades of flare loops form as a consequence of magnetic reconnection powering solar flares and eruptions. We analyze the morphology and evolution of flare arcades that formed during five well-known eruptive flares. We show that the arcades have a common saddle-like shape. The saddles occur despite the fact that the flares were of different classe…