L1489 IRS Esiplanetaarinen kiekko | Lähteet | NavigointivalikkoA deeply embedded young protoplanetary disk around L1489 IRS observed by the submillimeter arrayArtikkelin verkkoversioStructure and dynamics of the class I young stellar object L1489 IRS

Protoplanetaariset kiekot


esiplanetaarinen kiekkokiekkoMO





L1489 IRS on tähtitieteellinen kohde, nuori infrapunaa säteilevä tähti jolla on ympärillään esiplanetaarinen kiekko.[1] Keskustähden massa on arviolta 0,9-1,7 Auringon massaa.[2]



Esiplanetaarinen kiekko |


Kohteella on esiplanetaarinen kiekko, jonka massa on 0,01–0,03 MO. Kiekko ulottuu 0,1–2000 AU:n säteelle keskustähdestään.


Kohde saattaa olla siirtymäkohde pölyn peitossa olevien ja T Tauri -kohteiden välillä, ja siirtymät kestävät vain 20 000 vuotta. Kiekon lämpötilajakauma on T=19,4+(R/1000)–0,34. Tiheysjakauman potenssi on 1,8–2,1. Kiekon kaltevuus on jopa 60°. Kiekon litistyneisyys h/R on 0,35. Kiekko pyörii huomattavan nopeasti 300 AU:n sisässä vaikka koko kohde ulottuu 200 AU:n päähän. Massaa kasautuu 8*10−7 Auringon massaa vuodessa.


Kiekkoa ympäröivä vaippa on massaltaan arviolta 0,10 Auringon massaa[2][3].



Lähteet |



  1. ↑ C Brinch et al.: A deeply embedded young protoplanetary disk around L1489 IRS observed by the submillimeter array Astrophysics. 2007. Cornell University. Viitattu 6.3.2013.


  2. ↑ ab C Brinch et al.: Structure and dynamics of the class I young stellar object L1489 IRS. Astronomy & Astropysics, 2006 / 2011. Artikkelin verkkoversio (PDF) Viitattu 6.3.2013.


  3. ↑ 1.3 0.4 surrounded by a 0.10 flattened envelope with approximate scale height Structure and dynamics of the class I young stellar object L1489 IRS C. Brinch1, A. Crapsi1, M. R. Hogerheijde1, and J. K. Jørgensen








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