Search Publications
Binarity and beyond in A stars II. Disentangling the four stars in the vicinity of the triple HIP 87813 within the quintuple system HJ2814
Katz, Boaz; Waisberg, Idel; Klein, Ygal
A-type stars are the progenitors of about half of the white dwarfs (WDs) that currently exist. The observational mappings of both multiplicities are far from complete and their connection is not known. We are in the process of obtaining tight constraints on a sample of 108 southern and nearby A-stars that are part of the VAST sample by conducting …
Eclipse timing variations in the WD + dM eclipsing binary RR Cae
Reichart, D. E.; Awiphan, S.; Haislip, J. B. +9 more
We present the binary model and the eclipse timing variations of the eclipsing binary RR Cae, which consists of a white dwarf eclipsed by an M-type dwarf companion. The multiwavelength optical photometry from the Transiting Exoplanet Survey Satellite (TESS), the 0.6-m PROMPT-8 telescope, and the 0.7-m Thai Robotic Telescope at Spring Brook Observa…
How to improve our understanding of solar wind-magnetosphere interactions on the basis of the statistical evaluation of the energy budget in the magnetosheath?
Sorriso-Valvo, Luca; Plaschke, Ferdinand; Nakamura, Rumi +6 more
Solar wind (SW) quantities, referred to as coupling parameters (CPs), are often used in statistical studies devoted to the analysis of SW–magnetosphere–ionosphere couplings. Here, the CPs and their limitations in describing the magnetospheric response are reviewed. We argue that a better understanding of SW magnetospheric interactions could be ach…
Distribution and dynamics of decimetre-sized dust agglomerates in the coma of 67P/Churyumov-Gerasimenko
Agarwal, Jessica; Schröter, Matthias; Lemos, Pablo
We present a method to analyse images of the coma of 67P/Churyumov-Gerasimenko obtained using OSIRIS, the main imaging system on-board Rosetta, where dust aggregates can be seen as bright tracks because of their relative velocity with respect to the spacecraft. We applied this method to 105 images taken in 2015 July, 2015 December, and 2016 Januar…
Machine learning detection of dust impact signals observed by the Solar Orbiter
Mann, Ingrid; Vaverka, Jakub; Soucek, Jan +8 more
This article presents the results of automatic detection of dust impact signals observed by the Solar Orbiter - Radio and Plasma Waves instrument.
A sharp and characteristic electric field signal is observed by the Radio and Plasma Waves instrument when a dust particle impacts the spacecraft at high velocity. In this way, ∼ 5-20 dust impacts …An Ongoing Tidal Capture in the Large Magellanic Cloud: The Low-mass Star Cluster KMK 88-10 Captured by the Massive Globular Cluster NGC 1835?
Vesperini, Enrico; Cadelano, Mario; Pallanca, Cristina +6 more
In the context of a project aimed at characterizing the dynamical evolution of old globular clusters in the Large Magellanic Cloud, we have secured deep HST/WFC3 images of the massive cluster NGC 1835. In the field of view of the acquired images, at a projected angular separation of approximately 2' from the cluster, we detected the small stellar …
Three cases of optical periodic modulation in Active Galactic Nuclei
Wang, Zhongxiang; Li, Jie; Zheng, Dong
We report on the case of optical periodic modulation discovered in two Active Galactic Nuclei (AGN) and one candidate AGN. Analysing the archival optical data obtained from large transient surveys, namely the Catalina Real-Transient Survey (CRTS) and the Zwicky Transient Facility (ZTF), we find periodicities of 2169.7, 2103.1, and 1462.6 d in sour…
BD +30°549: a young helium-weak silicon star in the NGC 1333 star-forming region
Potravnov, I.; Ryabchikova, T.; Mashonkina, L.
We present results of the spectroscopic study of the chemically peculiar star BD +30°549, which is a bona fide member of the young NGC 1333 star-forming region. We found that the star possesses negligible rotation and a helium-weak spectroscopic pattern with strongly enhanced Si II and Si III lines. The fundamental parameters of the star, Tef…
Three-stage Collapse of the Long Gamma-Ray Burst from GRB 160625B Prompt Multiwavelength Observations
Rebolo, R.; Lipunov, V. M.; Kornilov, V. G. +37 more
This article presents the early results of synchronous multiwavelength observations of one of the brightest gamma-ray bursts (GRBs) GRB 160625B with the detailed continuous fast optical photometry of its optical counterpart obtained by MASTER and with hard X-ray and gamma-ray emission, obtained by the Lomonosov and Konus-Wind spacecraft. The detai…
Faint but Not Forgotten. I. First Results from a Search for Astrospheres around AGB Stars in the Far-ultraviolet
Sahai, Raghvendra; Stenger, Benjamin
Using the GALEX archive, we have discovered extended structures around ten asymptotic giant branch (AGB) stars (out of a total 92 searched) emitting in the far-ultraviolet (FUV) band. In all but one, we find the typical morphology expected for a spherical wind moving relative to, and interacting with, the interstellar medium (ISM) to produce an as…