Conversion Law of Infrared Luminosity to Star-Formation Rate for Galaxies

[摘要] Weconstructanewalgorithmforestimatingthestar-formationrate(SFR)ofgalaxiesfromtheirinfrared(IR)luminositybydevelopingthetheoryoftheIRemissionfromadustyHIIregion.ThederivedformulaisSFR$$/(M_odotextrm{yr}^{-1})=[3.3imes10^{-10}(1-eta)/(0.4-0.2f+0.6epsilon)](L^{obs}_{IR}/L_odot)$$,wherefisthefractionofionizingphotonsabsorbedbyhydrogen,εistheefficiencyofdustabsorptionfornonionizingphotonsfromOBstars,andηisthecirrusfractionofobservedIRluminosity.ThepreviousconversionformulaeofSFRfromtheIRluminosityareapplicabletoonlythecasewheretheobservedIRluminosityisnearlyequaltothebolometricluminosity(starburstgalaxiesetc.),exceptforsomeempiricalformulae.Ontheotherhand,ourtheoreticalSFRisapplicabletogalaxiesevenwithamoderatestar-formationactivity.Thatis,oursimpleandconvenientformulaissignificantlyusefulforestimatingtheSFRofvariousmorphologiesandtypesofgalaxies–fromearlyellipticaltolatespiralandirregulargalaxies,orfromactivestarbursttoquiescentgalaxies–aslongastheyhaveneitheranabnormaldust-to-gasrationoranevidentactivegalacticnucleus.

[学科分类] 天文学(综合)

[关键词] "galaxies: fundamental parameters";"infrared: galaxies";"ISM: dust";"methods: analytical";"stars: formation"