Related papers: Timing and spectral analysis of GK Persei during t…
The old nova and intermediate polar (IP) GK Persei underwent one of its recurrent dwarf nova (DN) outbursts in 2018. We proposed monitoring it in UV and X-rays with the Neil Gehrels Swift Observatory, starting less than six days after the…
The remarkable old nova and an intermediate polar (IP) - GK Per was observed with Swift, the Chandra HETG and NuSTAR during its recent dwarf nova (DN) outburst in March - April 2015. Monitoring the outburst, we noticed several processes…
The intermediate polar GK Per exhibited a dwarf nova outburst in March-April 2015. Suzaku X-ray telescope serendipitously captured the onset of the outburst during its pre-scheduled pointing observation spanning four days. In this paper, we…
GK Per, a classical nova of 1901, is thought to undergo variable mass accretion on to a magnetized white dwarf (WD) in an intermediate polar system (IP). We organized a multi-mission observational campaign in the X-ray and ultraviolet (UV)…
GK Persei is an intermediate polar that exhibits a dwarf nova outburst approximately every 1000 days. During previous outbursts the system has displayed kilo-second quasi-periodic oscillations (QPOs) in X-ray emission. These oscillations…
We report on NuSTAR observations of the Intermediate Polar GK Persei which also behaves as a Dwarf Nova. It exhibited a Dwarf Nova outburst in 2015 March-April. The object was observed in 3-79 keV X-rays with NuSTAR, once at the outburst…
The 2006 outburst of GK Perseii differed significantly at optical and ultraviolet wavelengths from typical outbursts of this object. We present multi-wavelength (X-ray, UV and optical) Swift and AAVSO data, giving unprecedented broad-band…
We detect the likely optical counterpart to previously reported X-ray QPOs in spectrophotometry of the intermediate polar GK Persei during the 1996 dwarf nova outburst. The characteristic timescales range between 4000--6000 s. Although the…
We report on X-ray observations of the Dwarf Nova GK Persei performed by {\it NuSTAR} in 2015. GK Persei, behaving also as an Intermediate Polar, exhibited a Dwarf Nova outburst in 2015 March--April. The object was observed with {\sl…
GK Per is a unique cataclysmic variable star which has showed a nova explosion as well as dwarf nova-type outbursts, and has the intermediate-polar nature. We carried out V-band time-resolved photometry and B-band monitoring during the 1996…
V392 Persei is a known dwarf nova (DN) that underwent a classical nova eruption in 2018. Here we report ground-based optical, Swift UV and X-ray, and Fermi-LAT \gamma-ray observations following the eruption for almost three years. V392 Per…
We present a complete dynamical study of the intermediate polar and dwarf nova cataclysmic variable GK Per (Nova Persei 1901) based on a multi-site optical spectroscopy and $R$-band photometry campaign. The radial velocity curve of the…
The eruption of Nova Persei 1901 (GK Per) occurred 125 yrs ago; remarkably it still holds major surprises. Using data from the Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer (SPHEREx), we find…
We present our X-ray and optical observations performed by NICER, NuSTAR, and Tomo-e Gozen during the 2023 outburst in the intermediate polar GK Persei. The X-ray spectrum consisted of three components: blackbody emission of several tens of…
AG Peg is known as the slowest symbiotic nova, which experienced its nova-like outburst around 1850. After 165 years, during June of 2015, it erupted again showing characteristics of the Z And-type outburst. The primary objective is to…
KT Eri is a classical nova which went into outburst in 2009. Recent photometric analysis in quiescence indicates a relatively longer orbital period of 2.6 days, so that KT Eri could host a very bright accretion disk during the outburst like…
We present results of a comprehensive analysis of the X-ray pulsar X Persei over the period 1996 to 2011, encompassing the quite low state and subsequent strong outburst activity. Using data from the RXTE and Swift observatories we detected…
Classical nova eruptions result from thermonuclear-powered runaways in, and ejection of, the hydrogen-rich envelopes of white dwarf stars accreted from their close binary companions. Novae brighten to up to 1,000,000 solar luminosities, and…
We analyse here four observations of nova KT Eri (Nova Eri 2009) done with the Chandra High Resolution Camera Spectrometer (HRC-S) and the Low Energy Transmission Grating (LETG) in 2010, from day 71 until day 159 after the optical maximum,…
We present early spectroscopy of the recurrent nova U~Sco during the outburst in 2010. We successfully obtained time-series spectra at $t_{\rm d}=$0.37--0.44~d, where $t_{\rm d}$ denotes the time from the discovery of the present outburst.…