Search Publications
X-ray observations of the nova shell IPHASX J210204.7+471015
Estrada-Dorado, S.; Guerrero, M. A.; Toalá, J. A. +4 more
We present the analysis of XMM-Newton European Photon Imaging Camera (EPIC) observations of the nova shell IPHASX J210204.7+471015. We detect X-ray emission from the progenitor binary star with properties that resemble those of underluminous intermediate polars such as DQ Herculis (DQ Her): an X-ray-emitting plasma with temperature of TX
Dissecting the Strong-lensing Galaxy Cluster MS 0440.5+0204. II. New Optical Spectroscopic Observations in a Wider Area and Cluster Dynamical State
Limousin, Marceau; Carrasco, Eleazar R.; Ellingson, E. +5 more
We present an optical study of the strong-lensing galaxy cluster MS 0440.5+0204 at z = 0.19593, based on CFHT/MegaCam g', r' photometry and GMOS/Gemini and CFHT/MOS/SIS spectroscopy in a broader area than previous works. We have determined new spectroscopic redshifts for the most prominent gravitational arcs surrounding the central galaxy in the c…
Distances for the RR Lyrae Stars UU Ceti, UW Gruis, and W Tucanae
Parker, R.; Banks, T.; Parker, L. +2 more
B, V, i, and z bandpass observations were collected in late 2020 for three RRab type stars: UU Ceti, UW Gruis, and W Tucanae. The period-luminosity (PL) relationships of Catalen, Pritzl, and Smith (2004, ApJSupp, 154) and Caceres and Catelan (2008, ApJSuppl, 179) were applied to derive distances. These were found to be in reasonable agreement with…
Detecting and analysing geomorphological structures in images of comet 67P/Churyumov-Gerasimenko using Fourier transform
Schröter, Matthias; Boehnhardt, Hermann; Pack, Andreas +1 more
We present a method for automatized detection and analysis of quasi-periodic lineament structures from images at pixel precision. The method exploits properties of the images' frequency domain found by using the Fourier transform. We developed this method with the goal of detecting lineament structures in an image of the Hathor cliff of comet 67P/…
A Simple Technique for Identifying the Propagation Direction of CMEs in 3D Space
Fainshtein, V. G.; Egorov, Y. I.
By now several methods have been proposed enabling to determine the kinematic characteristics of coronal mass ejections (CMEs) in 3D space. Many of these methods are based on using the triangulation technique and stereoscopic observations of the CMEs with two and more spacecraft. As a rule, these methods involve relatively complicated procedures. …
To the Globular Cluster Classification Problem. Calculating the Concentration of Stars for 26 Clusters
Nuritdinov, S. N.; Tatjibaev, I. U.; Rastorguev, A. S.
In view of the absence of a satisfactory solution to the globular cluster (GC) classification problem, we have searched for a physical parameter that admits of the GC classification and finding empirical dependences on observed physical characteristics. For this purpose, we have considered a model of the apparent density in GCs with three free par…
Erratum: UV and X-ray observations of the neutron star LMXB EXO 0748-676 in its quiescent state
Degenaar, N.; Wijnands, R.; Costantini, E. +5 more
The accretion behaviour in low-mass X-ray binaries (LMXBs) at low luminosities, especially at <E34 erg/s, is not well known. This is an important regime to study to obtain a complete understanding of the accretion process in LMXBs, and to determine if systems that host neutron stars with accretion-heated crusts can be used probe the physics of …
Machine learning for automatic identification of new minor species
Erwin, Justin; Daerden, Frank; Ristic, Bojan +9 more
One of the main difficulties to analyze modern spectroscopic datasets is due to the large amount of data. For example, in atmospheric transmittance spectroscopy, the solar occultation channel (SO) of the NOMAD instrument onboard the ESA ExoMars2016 satellite called Trace Gas Orbiter (TGO) had produced ~ 10 millions of spectra in ~ 20000 acquisitio…
XMM-Newton spectrum of the radio-loud quasar 3C 215: Slim accretion disk or SMBH binary
Tombesi, F.; Mei, A.
Context. Radio-loud active galactic nuclei (RL AGN) exhibit very powerful jet emission in the radio band, while the radio-quiet (RQ) AGN do not. This RL-RQ dichotomy would imply a sharp difference existing among these two classes, however, modern theoretical models and observations suggest a common nuclear environment that is possibly characterize…
Construction of a far-ultraviolet all-sky map from an incomplete survey: application of a deep learning algorithm
Jo, Young-Soo; Choi, Yeon-Ju; Kim, Min-Gi +3 more
We constructed a far-ultraviolet (FUV) all-sky map based on observations from the Far Ultraviolet Imaging Spectrograph (FIMS) aboard the Korean microsatellite Science and Technology SATellite-1. For the ${\sim}20{{\ \rm per\ cent}}$ of the sky not covered by FIMS observations, predictions from a deep artificial neural network were used. Seven data…