Llif yr atmosffer drydanol dros begwn y gogledd


Llif yr atmosffer drydanol dros begwn y gogledd
S. Eleri Pryse, Helen R. Middleton ac Alan G. Wood

Mae’r papur yn ymchwilio i strwythur ac ymddygiad yr atmosffer wedi’i ïoneiddio (trydanol) yn y nos yn yr ardaloedd pegynol ac awroraid; sef yr ardal lle y mae goleuni’r Gogledd yn digwydd. O ddiddordeb arbennig y mae strwythurau plasma ar raddfeydd llorweddol o gannoedd o gilometrau. Cafodd yr arsylwadau a gyflwynir eu gwneud gan arbrawf radiotomograffeg Prifysgol Cymru, Aberystwyth, y mae ganddi bedair system derbyn lloeren yn yr Arctig uchel ger pegwn y gogledd, yn Ny Ålesund a Longyearbyen ar Svalbard, Bjørnøya (Ynys yr Arth) a Tromsø ar dir mawr Norwy. Mae cymariaethau rhwng delweddau tomograffeg ac arsylwadau ar lif plasma gan y radar rhyngwladol, SuperDARN, yn awgrymu bod plasma dwysedd mawr a gynhyrchir ar ochr y dydd yn llifo ar draws yr ardal begynol ac i sector y nos. Mae’r canlyniadau yn cyfrannu at y gwaith o ddehongli prosesau ffisegol sy’n cysylltu amgylchedd y Ddaear â’r gofod, ac maent hefyd o ddiddordeb i ddefnyddwyr systemau radio lle gall yr atmosffer wedi’i ïoneiddio ddirywio ymlediad y signalau.


Cyfeiriad:

 
  	S. Eleri Pryse, Helen R. Middleton ac Alan G. Wood, 'Llif yr atmosffer drydanol dros begwn y gogledd: Arsylwadau tomograffi radio a SuperDARN', Gwerddon, 2, Hydref 2007, 35-50.
   

Allweddeiriau

 
    Atmosffer, pegwn y gogledd, radiotomograffeg, plasma, ffiseg, gofod.
    

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