Search Publications
Spectroscopic and imaging observations of transient hot and cool loops by IRIS and SDO
Gupta, Girjesh R.; Nayak, Sushree S.
Coronal loops are the basic building blocks of the solar atmosphere and are observed on various length scales. However, their formation mechanism is still unclear. In this paper, we present spectroscopic and imaging observations of small-scale transients and the subsequent formation of transient loops. For this purpose, we have utilized the multiw…
Calibrating the Cepheid Period-Wesenheit Relation in the Gaia Bands Using Galactic Open-cluster Cepheids
Xu, Ye; Liu, Dejian; Hao, Chaojie +3 more
Establishing the period-Wesenheit relation requires independent and accurate distance measurements of classical Cepheids (DCEPs). The precise distances provided by associated open clusters independently calibrate the period-Wesenheit relations of DCEPs. 51 DCEPs associated with open clusters are compiled using the constraints of five-dimensional a…
MeerKAT radio observations of the neutron star low-mass X-ray binary Cen X-4 at low accretion rates
Fender, R.; Miller-Jones, J. C. A.; van den Eijnden, J. +4 more
Centaurus X-4 (Cen X-4) is a relatively nearby neutron star low-mass X-ray binary that showed outbursts in 1969 and 1979, but has not shown a full outburst since. Due to its proximity and sustained period of quiescence, it is a prime target to study the coupling between accretion and jet ejection in quiescent neutron star low-mass X-ray binaries. …
Discovery of pulsating components in eclipsing binary systems through the TESS light curves: the cases of CPD-30 740, HD 97329, V1637 Ori and TYC 683-640-1
Ulaş, Burak; Ulusoy, Ceren; Erkan, Naci +2 more
We present the first evidence for the pulsations of primary components of four eclipsing binary systems. The TESS light curves of the targets are analyzed, the light and the absolute parameters are derived. Fourier analyses are applied to the residual data subtracted from the binary models to reveal the pulsational characteristics of the primaries…
Characterizing non-thermal equilibrium contact binaries
Wang, Z. H.; Zhu, L. Y.; Yuan, K.
Formation and evolution of marginal contact binaries with larger temperature difference between their two components remain inexplicable to date. To get a better understanding of the nature of such population we investigate on an individual, NSVS 7358116, by analysing observational data obtained from ground-based and space-based telescopes. It is …
A Comparative Study of Magnetic Flux Ropes in the Nightside Induced Magnetosphere of Mars and Venus
Harada, Yuki; Huang, Zesen; Luhmann, Janet G. +4 more
We analyzed Mars Atmosphere and Volatile Evolution (MAVEN) and Venus Express (VEX) data of magnetic flux ropes observed in both Mars and Venus nightside induced magnetosphere, in order to understand their statistical characteristics and possible formation processes. We statistically identified 382 (286) events at Mars (Venus) via the minimum varia…
On the trail of a comet's tail: A particle tracking algorithm for comet 67P/Churyumov-Gerasimenko
Agarwal, Jessica; Pfeifer, Marius; Schröter, Matthias
Context. During the post-perihelion phase of the European Space Agency's Rosetta mission to comet
A Hydro-based MCMC Analysis of SNR 0509-67.5: Revealing the Explosion Properties from Fluid Discontinuities Alone
Hughes, John P.; Arunachalam, Prasiddha; Hovey, Luke +1 more
Using Hubble Space Telescope/ACS Hα images of SNR 0509-67.5 taken ~10 yr apart, we measure the forward shock (FS) proper motions (PMs) at 231 rim locations. The average shock radius and velocity are 3.66 ± 0.036 pc and 6315 ± 310 km s-1. Hydrodynamic simulations, recast as similarity solutions, provide models for the supernova remnant's…
Study of the Magnetic Properties of Sunspot Umbrae
Obridko, V. N.; Fainshtein, V. G.; Rudenko, G. V. +1 more
The paper presents the results of the study of sunspots, obtained by the authors and other researchers in recent years. The results regarding the atmosphere above sunspot umbrae, based on the observational data in the spectral lines of the upper chromosphere and lower corona, are discussed. It is shown that individual parameters of the profile of …
Winds From the Visible (513 nm) Images Obtained by the Venus Monitoring Camera Onboard Venus Express
Ignatiev, N. I.; Zasova, L. V.; Titov, D. V. +4 more
We present more than 250,000 wind vectors derived from the visible (513 nm) images captured by the Venus Monitoring Camera (VMC) onboard ESA's Venus Express orbiter in the Southern hemisphere from 01 July 2007 to 29 January 2013. From comparison to the wind velocity derived from tracking of the descent probes, these measurements correspond to 60 ±…