Related papers: Orbital Periods for Three Recurrent Novae
We present the evolution of optical spectra and lightcurves of the fast nova V1674 Herculis during 150 days past its eruption. Using the post-eruption AAVSO light curve, we have calculated the orbital period of V1674 Her to be 0.153 days.…
Recurrent novae (RNe) are cataclysmic variables with two or more nova eruptions within a century. Classical novae (CNe) are similar systems with only one such eruption. Many of the so-called 'CNe' are actually RNe for which only one…
V1674 Her is one of the fastest novae, of which the very early phase is well observed including optical rise to the peak over 10 magnitudes. We present a full theoretical light curve model of V1674 Her. Our $1.35~M_\odot$ white dwarf (WD)…
Inspired by the discovery of the red nova V1309 Sco (Nova Scorpii 2008) and the fact that its progenitor was a binary system with a rapidly decreasing orbital period, we have searched for period changes in OGLE binary stars. We have…
We present high speed photometric observations of 20 faint cataclysmic variables, selected from the Sloan Digital Sky Survey and Catalina catalogues. Measurements are given of 15 new directly measured orbital periods, including four…
T CrB is one of the most-famous and brightest novae known, and is a recurrent nova with prior eruptions in 1866 and 1946 that peak at $V$=2.0. I have constructed light curves spanning 1842--2022 with 213,730 magnitudes, where the $B$ and…
We present results of 32 nights of CCD photometry of V1974 Cygni, from the years 1994 and 1995. We verify the presence of two distinct periodicities in the light curve: 0.0812585 day~1.95 hours and 0.0849767 d~2.04 hr. We establish that the…
The spectroscopic observations of two novae namely V1065 CEN and V1280 SCO were made by 45 cm Cassegrain telescope in high resolution ($\lambda/\delta\lambda$=22000) at H$\alpha$ (6563 \r{A}) region. V1065 CEN is He/N-type spectra which…
The only well-studied red nova progenitor (V1309 Sco) was a contact binary with a 1.4-day period. The prospects for searching for similar systems, as well as stellar merger candidates in general, are explored in this work. The photospheric…
According to recent theoretical studies, classical novae are expected to erupt every ~$10^5$ years, while the recurrence time scale of modern recurrent novae (N_r) stars ranges from 10 to ~100 years. To bridge this huge gap in our knowledge…
We present time-resolved CCD photometry of a dwarf nova NSV 4838 (UMa 8, SDSS J102320.27+440509.8) during the 2005 June and 2007 February outburst. Both light curves showed superhumps with a mean period of 0.0699(1) days for the 2005…
A CCD photometry of the dwarf nova MASTER OT J172758.09 +380021.5 was carried out in 2019 during 134 nights. Observations covered three superoutbursts, five normal outbursts and quiescence between them. The available ASASSN and ZTF data for…
This work extends the still modest number of multiple stars with known relative orbit orientation. Accurate astrometry and radial velocities are used jointly to compute or update outer and inner orbits in three nearby triple systems HIP…
Aims. NSV 13983 is catalogued as a dwarf nova based on a reported outburst from 2005. The system has not yet been studied spectroscopically. We attempt to confirm its nature as a dwarf nova and determine its orbital period. Methods. We…
Nova Her 2021 was observed with TESS 12.62 days after its most recent outburst in June 12.537 2021. This cataclysmic variable belongs to the intermediate polar class, with an spin period of $\sim$501 s and orbital period of 0.1529 days.…
Spectroscopic orbits are determined for inner subsystems in nine stellar hierachies (HIP 2863, 4974, 8353, 28796, 35261, 92929, 115272, 115552, and 117596). Their periods range from 2.5 to 312 days. For each system, estimates of masses,…
The orbital period of Scorpius X-1 has been accepted as 0.787313 d since its discovery in archival optical photometric data by Gottlieb, Wright, & Liller (1975). This period has been confirmed in both photometric and spectroscopic optical…
In recent years, several nova explosions have been detected by Fermi/LAT at E>100 MeV, mainly early after the explosion and for a short period of time. The first evidence of particle acceleration in novae was found in the 2006 eruption of…
We report spectroscopy of the newly discovered SU Ursae Majoris dwarf nova identified with the x-ray source RXS J053234.9+624755. Radial velocities of the H-alpha emission line in the quiescent state give an orbital period of 0.05620(4) d…
We have performed a Discrete Fourier Transform on 136 CCD B, V and R frames of the Z Cam-type dwarf nova V1101 Aql. Our analysis indicates as possible orbital period P_orb =3.46 hours, though we cannot exclude the alias at 4.00 hours. We…