Evolution of the Sheared Magnetic Fields of Two X-Class Flares Observed by Hinode/XRT

[摘要] Wepresentmulti-wavelengthobservationsoftheevolutionoftheshearedmagneticfieldsinNOAAActiveRegion10930,wheretwoX-classflaresoccurredon2006December13andDecember14,respectively.ObservationsmadewiththeX-rayTelescope(XRT)andtheSolarOpticalTelescope(SOT)aboardHinodesuggestthatthegradualformationoftheshearedmagneticfieldsinthisactiveregioniscausedbytherotationandwest-to-eastmotionofanemergingsunspot.Inthepre-flarephaseofthetwoflares,XRTshowsseveralhighlyshearedX-rayloopsinthecorefieldregion,correspondingtoafilamentseenintheTRACEEUVobservations.XRTobservationsalsoshowthatpartoftheshearedcorefielderupted,andanotherpartoftheshearedcorefieldstayedbehindduringtheflares,whichmayexplainwhyalargepartofthefilamentisstillseenbyTRACEaftertheflare.About2–3hoursafterthepeakofeachflare,thecorefieldbecomesvisibleinXRTagain,andshowsahighlyshearedinnerandless-shearedouterstructure.Wealsofindthatthepost-flarecorefieldisclearlylessshearedthanthepre-flarecorefield,whichisconsistentwiththeideathattheenergyreleasedduringtheflaresisstoredinthehighlyshearedfieldspriortotheflare.

[学科分类] 天文学(综合)

[关键词] "Sun: corona";"Sun: filaments;prominences";"Sun: flares";"Sun: magnetic fields";"Sun: X-rays;gamma rays"