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تسجيل مستخدم جديدSimultaneous Multiwavelength Flare Observations of EV Lacertae
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We present the first results of our ongoing project conducting simultaneous multiwavelength observations of flares on nearby active M dwarfs. We acquired data of the nearby dM3.5e star EV Lac using 5 different observatories: NASAs Transiting Exoplanet Survey Satellite (TESS), NASAs Neil Gehrels Swift Observatory (textit{Swift}), NASAs Neutron Interior Composition Explorer (NICER), the University of Hawaii 2.2-m telescope (UH88) and the Las Cumbres Observatory Global Telescope (LCOGT) Network. During the $sim$25 days of TESS observations, we acquired three simultaneous UV/X-ray observations using textit{Swift} that total $sim$18 ks, 21 simultaneous epochs totaling $sim$98 ks of X-ray data using NICER, one observation ($sim$ 3 hours) with UH88, and one observation ($sim$ 3 hours) with LCOGT. We identified 56 flares in the TESS light curve with estimated energies in the range log $E_{rm T}$ (erg) = (30.5 - 33.2), nine flares in the textit{Swift} UVM2 light curve with estimated energies in the range log $E_{UV}$ (erg) = (29.3 - 31.1), 14 flares in the NICER light curve with estimated minimum energies in the range log $E_{N}$ (erg) = (30.5 - 32.3), and 1 flare in the LCOGT light curve with log $E_{L}$ (erg) = 31.6. We find that the flare frequency distributions (FFDs) of TESS and NICER flares have comparable slopes, $beta_{T}$ = -0.67$pm$0.09 and $beta_{N}$ = -0.65$pm$0.19, and the FFD of UVOT flares has a shallower slope ($beta_{U}$ = -0.38$pm$0.13). Furthermore, we do not find conclusive evidence for either the first ionization potential (FIP) or the inverse FIP effect during coronal flares on EV Lac.
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