Ýçindekiler
Görüntüler
Resim Yükleyin
DSS Images Other Images
Ýlgili Makaleler
Spectropolarimetry and Radiative Transfer Modeling of Three Proto-Planetary Nebulae
We measured the spectrum of polarization for three proto-planetarynebulae (PPNs), IRAS 17411-2411, IRAS 08005-2356, and IRAS 04296+3429,and made model calculations with the dust-scattering Monte Carlo codeDIRTY and the dust emission code 2Dust. We show that high levels ofpolarization in these PPNs correlate with extreme asymptotic giantbranch (AGB) superwind mass-loss rates in excess of 10-4Msolar yr-1. All three objects show evidence forevacuated lobes cleared by collimated fast winds, and two indicate asignificant equatorial mass enhancement. Our best-fit models requiresharply peaked grain size distributions, suggesting that most of thelight is being scattered by grains of a characteristic size in IRAS17441-2411 and IRAS 08005-2356. IRAS 17441-2411 and IRAS 08005-2356 havelobes with wide opening angles, perhaps produced by deflection of apolar jet from an accreting companion by the AGB superwind. Modeling thespectropolarimetry of IRAS 04296+3429 indicates a point-symmetric,multipolar morphology in the PPN phase. The modeling ofspectropolarimetry and other observations of PPNs provides a powerfulway to constrain circumstellar morphology and dust parameters.
|
Yeni bir Makale Öner
Ýlgili Baðlantýlar
Yeni Bir Baðlantý Öner
sonraki gruplarýn üyesi:
|
Gözlemler ve gökölçümü verileri
| Takýmyýldýz: | Zurafa |
| Sað Açýklýk: | 05h00m50.45s |
| Yükselim: | +54°35'04.1" |
| Görünürdeki Parlaklýk: | 8.655 |
| Uzaklýk: | 169.492 parsek |
| özdevim Sað Açýklýk: | -20.2 |
| özdevim Yükselim: | -1.4 |
| B-T magnitude: | 9.197 |
| V-T magnitude: | 8.7 |
Kataloglar ve belirtme:
|
INHABITED SKY
