Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul


Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul
Jeff Smith

Mae’r Haul yn system ddynamig, gymhleth, sy’n llawn nodweddion diddorol a phwysig. Gellir modelu’r fath nodweddion drwy sawl dull, e.e. modelau Meysydd Di-rym Aflinol (NLFFF: non-linear force-free field). Yn y papur hwn, adeiladir efelychiadau NLFFF. Y bwriad yw amcangyfrif patrymau gofodol y maes magnetig yng nghromosffer a chorona’r Haul ynghyd â newidiadau yn yr egni rhydd sydd yn y system, fel colledion egni oherwydd ffrwydradau ar yr Haul. Mae gan y rhan fwyaf o fodelau sydd eisoes yn bodoli gydraniad amserol (temporal cadence) o 12 munud ar y gorau (h.y. efelychir y sefyllfa bob 12 munud). Mae’r dull a drafodir yn y papur hwn yn gwneud sawl bras amcan ond mae’n anelu at gyrraedd cydraniad amserol o 45 eiliad. Canfyddir bod y dull a ddefnyddir yma yn efelychu data synthetig yn llwyddiannus, ac wrth ymdrin â data go iawn, mae’n cynhyrchu delweddau sy’n aml yn cyfateb yn dda i arsylwadau. Gwelir sawl cwymp yn yr egni rhydd o fewn y system, sy’n cyfateb i ffrwydradau yr arsylwyd arnynt. Gyda hynny, rhoddir golwg newydd ar brosesau cyflym sydd i’w gweld ar yr Haul.


Cyfeiriad:

 
  	Jeff Smith, 'Model amldonfedd i ddelweddu a dadansoddi meysydd magnetig yng nghorona’r Haul', Gwerddon, 18, Medi 2014, 23-40.
   

Allweddeiriau

 
    Haul, NLFFF, lwpiau'r corona, efelychu, ffrwydrad, osgiliadau, egni.
    

Llyfryddiaeth:

 
  	
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