Swift and XMM-Newton observations of an RS CVn type eclipsing binary SZ Psc: Superflare and coronal properties

Abstract

We present an in-depth study of a large and long duration ($>$1.3 days) X-ray flare observed on an RS CVn type eclipsing binary system SZ Psc using observations from Swift observatory. In the 0.35$-$10 keV energy band, the peak luminosity is estimated to be 4.2$\times$10${}^{33}$ erg s${}^{-1}$. The quiescent corona of SZ Psc was observed $\sim$5.67 d after the flare using Swift observatory, and also $\sim$1.4 yr after the flare using the XMM-Newton satellite. The quiescent corona is found to consist of three temperature plasma: 4, 13, and 48 MK. High-resolution X-ray spectral analysis of the quiescent corona of SZ Psc suggests that the high first ionization potential (FIP) elements are more abundant than the low-FIP elements. The time-resolved X-ray spectroscopy of the flare shows a significant variation in the flare temperature, emission measure, and abundance. The peak values of temperature, emission measure, and abundances during the flare are estimated to be 199$\pm$11 MK, 2.13$\pm$0.05 $\times 10^{56}$ cm${}^{-3}$, 0.66$\pm$0.09 Z${}_{\odot }$, respectively. Using the hydrodynamic loop modeling, we derive the loop length of the flare as 6.3$\pm$0.5 $\times 10^{11}$ cm, whereas the loop pressure and density at the flare peak are derived to be 3.5$\pm$0.7 $\times 10^3$ dyne cm${}^{-2}$ and 8$\pm$2 $\times 10^{10}$ cm${}^{-3}$, respectively. The total magnetic field to produce the flare is estimated to be 490$\pm$60 G. The large magnetic field at the coronal height is supposed to be due to the presence of an extended convection zone of the sub-giant and the high orbital velocity.

23 pages, 12 figures, 5 tables, accepted for publication in MNRAS

References in corpus (16)

• HI4PI: A full-sky HI survey based on EBHIS and GASS
• X-ray flares in Orion young stars. I. Flare characteristics
• Diagnostics of stellar flares from X-ray observations: from the decay to the rise phase
• Nonthermal Hard X-ray Emission and Iron Kalpha Emission from a Superflare on II Pegasi
• Scaling laws of solar and stellar flares
• A study of X-ray flares - I. Active late-type dwarfs
• Modelling the spectral response of the Swift-XRT CCD camera: Experience learnt from in-flight calibration
• Large X-ray Flares on Stars Detected with MAXI/GSC: A Universal Correlation between the Duration of a Flare and its X-ray Luminosity
• Abundance variations and first ionization potential trends during large stellar flares
• The FIP and Inverse FIP Effects in Solar Flares
• The RS CVn type star GT Mus shows most energetic X-ray flares throughout the 2010s
• Prominence activation, optical flare, and post-flare loops on the RS Canum Venaticorum star SZ Piscium
• X-ray flares on the UV Ceti-type star CC Eridani: a "peculiar" time-evolution of spectral parameters
• X-Ray Superflares on CC Eri
• LO Peg: surface differential rotation, flares, and spot-topographic evolution
• An X-ray flare from 47 Cas