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Mass Transfer as an Explanation for the Lifetime Travel Time Discrepancy in IT Librae
Orosz, Jerome; Shepard, Katherine; Wysocki, Peter +2 more
The eclipsing binary IT Librae is an unusual system of two B-type stars that is situated about 1 kpc above the Galactic plane. The binary was probably ejected from its birthplace in the disk, but the implied time of flight to its current location exceeds the evolutionary lifetime of the primary star. Here we present a study of new high-dispersion …
Stringent limits on 28SiO maser emission from the recurrent nova T Coronae Borealis
Munari, U.; Evans, A.; Pimpanuwat, B. +5 more
There are indications that the third-known eruption of the recurrent nova T CrB is imminent, and multiwavelength observations prior to the eruption are important to characterize the system before it erupts. T CrB is known to display the SiO fundamental vibrational feature at 8 $\, \mu$m. When the anticipated eruption occurs, it is possible that th…
Shadow method retrievals of the atmospheric optical depth above Gale crater on Mars using HRSC images
Hoekzema, N. M.; Shaheen, Farzana; Scariah, Nayama Valsa +3 more
The 'Shadow Method' is a tool to estimate the Atmospheric Optical Depth (AOD) on Mars from the brightness of shadows. This method is derived from the equations of radiative transfer, but there are several important simplifications that together invoke errors of several tens of percent. Work by us and by others show that these errors are largely sy…
A Comparative Analysis of Quasi-Periodic Processes in the Magnetospheric Current Sheet and the Current Sheets of the Solar Corona
Zimovets, I. V.; Lukin, A. S.; Artemiev, A. V.
Reconnection of magnetic field lines represents a universal process of releasing the stored energy of the magnetic field and its transformation into the thermal energy of plasma and the energy of accelerated charged particles. The initialization and proceeding of the magnetic reconnection process are essentially related with the dynamics of a spat…
Optical Time-series Photometry of the Symbiotic Nova V1835 Aquilae
Layden, Andrew C.; Caddy, Robert V.; Reichart, Daniel E. +7 more
We present time-series CCD photometry in the BVRI passbands of the recently identified symbiotic nova V1835 Aquilae (NSV 11749) over an interval of 5.1 yr with 7-14 day cadence, observed during its quiescence. We find slow light variations with a range of ~0.9 mag in V and ~0.3 mag in I. Analysis of these data show strong periodicity at 419 ± 10 d…
On Some Issues of Cross-Identification of Astronomical Catalogs
Sobolev, A. M.; Ladeyschikov, D. A.
The paper deals with the issues of cross-identification of sources from various astronomical catalogs. One of the main problems under consideration is how to cross-identify a large number of catalogs in a selected region in the sky when there is no reference source catalog? For cross-identification of large amounts of data, it is proposed to use t…
Near-infrared Spectroscopy of Ultracompact H II Regions in W51A with NIFS/ALTAIR
Damineli, Augusto; Navarete, Felipe; Conti, Peter S. +2 more
W51A is the most active star formation region of the giant H II region W51. It harbors the two massive protoclusters W51e and W51 IRS2, which are very rare in the Galaxy. We aim to identify the newborn massive stars and ultracompact H II regions to derive its distance and age. We performed Integral Field Unit observations with NIFS+ALTAIR of nine …
The overcontact binary SS arietis
Nelson, Robert H.
New radial velocity and photometric data for SS Ari have been obtained and analysed using the 2003 versions of the Wilson-Devinney code. Values for fundamental quantities have been obtained: M1 = 0.510 (15) M⊙, M2 = 1.521 (26) M⊙, R1 = 0.87 (2) R⊙, R2 = 1.42 (2) R⊙
The two eccentric eclipsing binaries in multiple systems: V539 Arae and V335 Serpentis
Wolf, M.; Zejda, M.; Mašek, M. +4 more
We present new results of our long-term observational project to analyze the variations of the orbital period for early-type eccentric eclipsing binaries. Altogether 77 new mid-eclipse times were measured or derived for two eclipsing binaries, namely V539 Ara and V335 Ser. Based on current O - C diagrams, we found in both systems that times of min…
First TESS light curve solution and orbital period analysis of V567 And
Öztürk, Oğuz
The photometric light curve of V567 And observed by the Transiting Exoplanet Survey Satellite (TESS) was solved for the first time in this study. According to the final model parameters, it was concluded that the system is a semi-detached eclipsing binary star system. The mass and radius values of the primary and secondary components were estimate…