Swift observations of CC Eri: X-ray superflare

We present an analysis of a superflare detected on an active binary system CC Eridani by Swift observatory. The flare (F1) triggered the Burst Alert Telescope (BAT) in the hard X-ray band on 2008 October 16. The rise-phase was observed only with BAT, whereas the decay phase was observed simultaneously with X-Ray Telescope (XRT). The e-folding decay time indicates a faster decay in the hard X-ray band than in the soft X-ray band. Spectral analysis indicates a presence of three temperature corona with first two plasma temperatures remain constant during the flare at ∼3 and ∼10 MK. The flare-temperature peaked at 342 MK which is ∼4 times more than the minimum value observed at post-flaring (PF) phase. The abundances peaked at 2 times the solar abundances, which is also ∼11 times larger than the quiescent state value. Using hydrodynamic loop modeling we derive a loop-length of 1.25±0.13×10^{10} cm. The peak X-ray luminosity for flares F1 in the 0.3–50 keV energy band (excluding 10–14 keV band) reached up to ∼4×10^{32} erg s^{−1} , which is ∼3500 times more than the quiescent value and larger than any other flares previously observed on CC Eri.