Temperature Distributions and Energy Scaling Law of Solar Coronal Loops Obtained with Yohkoh

Publications of the Astronomical Society of Japan

Kano, Ryouhei¹  Tsuneta, Saku¹ 

[1] Institute of Astronomy, The University of Tokyo, Mitaka, Tokyo 181 E-mail{RK):

关键词: Magnetohydrodynamics;    "Sun: activity";    "Sun: corona";    "Sun: X-rays";   

DOI  :  10.1093/pasj/48.3.535

学科分类：天文学(综合)

来源: Oxford University Press

【 摘 要 】

Wederivedthetemperaturedistributionsalongthe16steadyloopsobservedwiththeYohkohSoftX-rayTelescope.Wehavefoundthatthetemperatureandemissionmeasure(pressure)arethehighestaroundthelooptop,anddecreasetowardsthefootpoints.Someoftheloopshaveaplateauinthetemperaturedistributionataroundthelooptop(“trapezoidal”temperaturedistribution).Theotherloops,ontheotherhand,haveasharppeakinthetemperaturedistributions(“triangular”temperaturedistribution).Thistriangulartemperaturedistributionsuggeststhattheenergyinputisconcentratedatthepeak.Wehaveestimatedthethermalconductivefluxesdownwardtothefootpointsfromthegradientsofthetemperaturedistributions.Thefluxrangesfrom1×107to2×108[ergs−1cm−2].WederivedthetotalenergylossLT,whichisthesumoftheconductiveandradiativelosses:LT=2×107−3×108[ergs−1cm−2].WediscoveredagoodcorrelationbetweenthetotalenergylossandthegaspressurePgforthesteadyloops:LT=1.2×107p0.99±0.12g.Thecorrelationisconsistentwiththetheoreticalenergyscalinglawforthesteadyloops:LT=4.0–5.1×103·(pg·Tm1/2),whereTmisthemaximumtemperature(Tm∼6×106[K]foralltheloopsanalyzedhere).

【 授权许可】

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