MAGNETIC FIELD STRUCTURES AND TURBULENT COMPONENTS IN THE STAR-FORMING MOLECULAR CLOUDS OMC-2 AND OMC-3

Autor(es)

Poidevin, Frederick ^[1] ; Bastien, Pierre ^{[2, 3]} ; Matthews, Brenda C. ^[4]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Astron Geofis & Ciencas Atmosfer, BR-05508900 Sao Paulo - Brazil

^[2] Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7 - Canada

^[3] Univ Montreal, Observ Mt Megant, Montreal, PQ H3C 3J7 - Canada

^[4] Natl Res Council Canada, Herzberg Inst Astrophys, Victoria, BC - Canada

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 716, n. 2, p. 893-906, JUN 20 2010.
• Citações Web of Science: 25

Resumo

The SCUBA polarized 850 mu m thermal emission data of the OMC-2 region in Orion A are added to and homogeneously reduced with data already available in the OMC-3 region. The data set shows that OMC-2 is a region generally less polarized than OMC-3. Where coincident, most of the 850 mu m polarization pattern is similar to that measured in 350 mu m polarization data. Only 850 mu m polarimetry data have been obtained in and around MMS7, FIR1 and FIR2, and in the region south of FIR6. A realignment of the polarization vectors with the filament can be seen near FIR1 in the region south of OMC-3. An analysis shows that the energy injected by CO outflows and H(2) jets associated with OMC-2 and OMC-3 does not appear to alter the polarization patterns at a scale of the 14 `' resolution beam. A second-order structure function analysis of the polarization position angles shows that OMC-2 is a more turbulent region than OMC-3. OMC-3 appears to be a clear case of a magnetically dominated region with respect to the turbulence. However, for OMC-2 it is not clear that this is the case. A more in-depth analysis of five regions displayed along OMC-2/3 indicates a decrease of the mean polarization degree and an increase of the turbulent angular dispersion from north to south. A statistical analysis suggests the presence of two depolarization regimes in our maps: one regime including the effects of the cores, the other one excluding it. (AU)

• Processo FAPESP: 07/56302-4 - O campo magnético da galáxia
• Beneficiário: Frederic Nicolas David Poidevin
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado