Search Publications
Missions
Journals
Publication Years
Multipoint Analysis of the Interaction between a Shock and an ICME-like Structure around 2011 March 22
Wang, Yuming; Shen, Chenglong; Xu, Mengjiao +3 more
This work reports on the interaction between a fast forward shock and an interplanetary coronal-mass-ejection-like structure (ICMELS) as observed by in situ observations of radially aligned spacecraft. Around 2011 March 22, the Venus EXpress (VEX) and Solar TErrestrial RElations Observatory-A (STEREO-A) were nearly at the same longitude, providing…
Spectroscopic Line Modeling of the Fastest Rotating O-type Stars
Gies, Douglas R.; Shepard, Katherine; Kaper, Lex +1 more
We present a spectroscopic analysis of the most rapidly rotating stars currently known, VFTS 102 ( ${v}_{e}\sin i=649\pm 52$ km s-1; O9: Vnnne+) and VFTS 285 ( ${v}_{e}\sin i=610\pm 41$ km s-1; O7.5: Vnnn), both members of the 30 Dor complex in the Large Magellanic Cloud. This study is based on high-resolution ultraviolet spe…
Unveiling wide-orbit companions to K-type stars in Sco-Cen with Gaia EDR3
Henning, Thomas; Brown, Anthony G. A.; Ginski, Christian +12 more
Context. The detection of low-mass companions to stellar hosts is important for testing the formation scenarios of these systems. Companions at wide separations are particularly intriguing objects as they are easily accessible for variability studies of the rotational dynamics and cloud coverage of these brown dwarfs or planetary-mass objects.
On the Evolution of a Sub-C Class Flare: A Showcase for the Capabilities of the Revamped Catania Solar Telescope
Spadaro, Daniele; Guglielmino, Salvo L.; Romano, Paolo +9 more
Solar flares are occasionally responsible for severe space-weather events, which can affect space-borne and ground-based infrastructures, endangering anthropic technological activities and even human health and safety. Thus, an essential activity in the framework of space-weather monitoring is devoted to the observation of the activity level on th…
Long-term variation of coronal holes latitudinal distribution
Chargeishvili, B. B.; Maghradze, D. A.; Japaridze, D. R. +2 more
We study the evolution of the latitudinal distribution of coronal holes using the Solar and Heliospheric Observatory (SOHO)/Extreme ultraviolet Imaging Telescope (EIT) 195 Å data from 1996 May to 2020 April. To measure the presence of coronal holes at a given latitude, we use the presence factor, which estimates the length of an object along a giv…
Infrared-radio relation in the local Universe
De Zotti, G.; Tisanić, K.; Amiri, A. +3 more
Context. The Square Kilometer Array (SKA) is expected to detect high-redshift galaxies with star formation rates (SFRs) up to two orders of magnitude lower than Herschel surveys and will thus boost the ability of radio astronomy to study extragalactic sources. The tight infrared-radio correlation offers the possibility of using radio emission as a…
The Orbits and Dynamical Masses of the Castor System
Torres, Guillermo; Klement, Robert; Monnier, John D. +12 more
Castor is a system of six stars in which the two brighter objects, Castor A and B, revolve around each other every ~450 yr and are both short-period spectroscopic binaries. They are attended by the more distant Castor C, which is also a binary. Here we report interferometric observations with the Center for High Angular Resolution Astronomy (CHARA…
Search for Close Stellar Encounters with the Solar System Based on Data from the Gaia DR3 Catalogue
Bobylev, V. V.; Bajkova, A. T.
We have searched for close stellar encounters with the Solar System using data from the Gaia DR3 catalogue. We have considered 31 stars with an encounter parameter $d_min<1$ pc. Among them 15 stars act as candidates for close encounters for the first time. The status of the stars GJ 710 and HD 7977 as candidates for deep penetration into the in…
At What Mass Are Stars Braked? The Implication from the Turnoff Morphology of NGC 6819
Huang, Yang; Li, Chengyuan; Yang, Yong +1 more
Extended main-sequence turnoffs (eMSTOs) apparent in most young and intermediate-age clusters (younger than ~2 Gyr) are known features caused by fast rotating early-type (earlier than F-type) stars. Late-type stars are not fast rotators because their initial angular momenta have been quickly dispersed due to magnetic braking. However, the mass lim…
Abundance of zirconium in the globular cluster 47 Tucanae: a possible Zr-Na correlation?*
Bonifacio, P.; Korotin, S.; Kučinskas, A. +2 more
We determined abundances of Na and Zr in the atmospheres of 237 RGB stars in Galactic globular cluster (GGC) 47 Tuc (NGC 104), with a primary objective of investigating possible differences between the abundances of Zr in the first generation (1P) and second generation (2P) stars. For the abundance analysis, we used archival UVES/GIRAFFE spectra o…