Related papers: Identifying and Quantifying Recurrent Novae Masque…
We report on studies of Classical Nova (CN) explosions where we follow the evolution of thermonuclear runaways (TNRs) on oxygen-neon (ONe) white dwarfs (WDs). Using NOVA, a one-dimensional hydrodynamic computer code, we accrete Solar matter…
A classical nova results from runaway thermonuclear explosions on the surface of a white dwarf that accretes matter from a low-mass main-sequence stellar companion. In 2012 and 2013, three novae were detected in gamma rays and stood in…
We detected the second historical outburst of the 1920 nova IM Nor. Accurate astrometry of the outbursting object revealed the true quiescent counterpart having a magnitude of R=17.0 mag and B=18.0 mag. We show that the quiescent…
I review X-ray observations of classical and recurrent novae in outburst. Significant X-ray flux is emitted by the nova shell, with a peak luminosity up to 10**35 erg/cm**2/s in the 0.2-10 keV range.In recurrent nova systems, or in novae…
X-ray emission from counterparts of historical classical novae (CNe) in our Galaxy is studied. To this end, we use data from three SRG/eROSITA sky surveys in the hemisphere analyzed by the RU eROSITA consortium. Out of 309 historical CNe,…
Classical Novae were revealed as a surprise source of gamma-rays in Fermi LAT observations. During the first 8 years since the LAT was launched, 6 novae in total have been detected to > 5 sigma in gamma-rays, in contrast to the 69…
The properties of the young pulsars and their relations to the supernova remnants (SNRs) have been the interesting topics. At present, 383 SNRs in the Milky Way galaxy have been published, which are associated with 64 radio pulsars and 46…
(Abridged) White dwarfs (WDs) undergoing unstable nuclear burning on their surfaces, resulting in the nova phenomenon, have been considered as one of the prospective candidates for the still elusive progenitors of SNeIa. We propose that…
Planetary nebulae (PNe) are strong H$\alpha$ line-emitters and a lot of new PNe discoveries have been made by the SuperCOSMOS AAO/UKST H$\alpha$ Survey (SHS) and the Isaac Newton Telescope Photometric H$\alpha$ Survey (IPHAS). However, the…
We examine the case for Quark-Novae (QNe) as possible sources for the reionization and early metal enrichment of the universe. Quark-Novae are predicted to arise from the explosive collapse (and conversion) of sufficiently massive neutron…
The Pan-STARRS (PS1) Medium Deep Survey discovered over 5,000 likely supernovae (SNe) but obtained spectral classifications for just 10% of its SN candidates. We measured spectroscopic host galaxy redshifts for 3,147 of these likely SNe and…
For Galactic novae, I calculate and collect a comprehensive catalog of 208 measures of white dwarf (WD) masses ($M_{\rm WD}$) and 232 measures of average $V$ magnitudes in quiescence ($V_q$). These are collected into a comprehensive catalog…
The majority of thermonuclear explosions in the Universe seem to proceed in a rather standardised way, as explosions of carbon-oxygen (CO) white dwarfs in binary systems, leading to 'normal' Type Ia supernovae (SNe Ia). However, over the…
We report the results of a multi-year spectroscopic and photometric survey of novae in M31 that resulted in a total of 53 spectra of 48 individual nova candidates. Two of these, M31N 1995-11e and M31N 2007-11g, were revealed to be…
During the first few days after explosion, Type II supernovae (SNe) are dominated by relatively simple physics. Theoretical predictions regarding early-time SN light curves in the ultraviolet (UV) and optical bands are thus quite robust. We…
We survey our understanding of classical novae: non-terminal, thermonuclear eruptions on the surfaces of white dwarfs in binary systems. The recent and unexpected discovery of GeV gamma-rays from Galactic novae has highlighted the…
We present a sample of Type Icn supernovae (SNe Icn), a newly-discovered class of transients characterized by their interaction with H- and He-poor circumstellar material (CSM). This sample is the largest collection of SNe Icn to date and…
Core-collapse supernovae (SNe) expand into a medium created by winds from the pre-SN progenitor. The SN explosion and resulting shock wave(s) heat up the surrounding plasma, giving rise to thermal X-ray emission, which depends on the…
Type Ia-CSM supernovae (SNe) are a rare and peculiar subclass of thermonuclear SNe characterized by emission lines of hydrogen or helium, indicative of a high-density circumstellar medium (CSM). Their implied mass-loss rates of $\sim…
During the last few years, a number of exceptional core-collapse supernovae (SNe) have been discovered. Their kinetic energy of the explosions are larger by more than an order of magnitude than the typical values for this type of SNe, so…