The statistical analyses of flares detected in B band photometry of UV Ceti type stars

Abstract

In this study, we present the unpublished flare data collected from 222 flares detected in B band observations of five stars and the results derived by the statistical analysis and modelling of these data. Using a statistical analysis method, six basic properties have been found from all models and analyses for the flares detected in B band observation of UV Ceti type stars. We have also compare U and B bands in respect to the analysis results. This gave us a chance to test whether the methods using in the analyses are statistically trustworthy, or not. According to the analyses, 1) The flares were separated into two types as fast and slow flares. 2) There is 16.2±3.7 times difference between the mean averages of the equivalent durations of the slow and the fast flares. 3) It is no matter how long the flare total durations, maximum flare energy can reach a different Plateau level of energy for each star. 4) The Plateau values of EV Lac and EQ Peg are absolutely higher than the others. 5) Minimum values of the flare total durations increase toward the later spectral types. This value is called Half-Life value in models. 6) Both maximum flare rise times and flare total durations obtained from the observed flares are decreasing toward the later spectral type.

Investigating magnetic activity in very stable stellar magnetic fields

“…Flare energy values are only estimated for those events, which are covered sufficiently by multicolour observations. Studies dedicated to photometric monitoring of dMe stars, such as EV Lac and AD Leo (Leto et al 1997;Dal & Evren 2012), detected several flares in the B band with energies up to 10 33 erg, which fits the determined flare energies of V374 Peg very well. Moreover, the most energetic solar flares show total energies up to 10 33 erg (Schrijver et al 2012;Kretzschmar et al 2010).…”

Flux emergence, flux imbalance, magnetic free energy and solar flares

“…Recent high spatial resolution observations of sunspot configuration and magnetic field measurements show that the spot area changes due to permanent changes in magnetic field configuration (Wang et al, 2001;Liu et al, 2005). The relation of stellar flares to the spotted area on the stellar surface adds to the notion that the spot area can be used to study the flare occurrence rate and estimate the total flare energy release at the active region (Dal and Evren, 2012).…”

Lamost Observations of Flaring M Dwarfs in the Kepler Field

“…Because of the strong magnetic activity associated with their convective envelopes, the M dwarfs (dM stars) are known to have frequent flares, especially in the case of the late-type stars (i.e., M3 -M9) according to Hilton (2011). UV Ceti-type flares have been well-documented even though whether the generation mechanism is similar to that of solar flares is still uncertain (Moffett, 1974;Dal and Evren, 2012). Because the evolution of the M dwarfs are closely relevant to the dM stars interesting issue of exoplanetary habitability (Tarter et al, 2007), it is therefore interesting to investigate their flare phenomena.…”