多極行星狀星雲NGC 2440和NGC 6302的分子分佈

Abstract

The CO(3-2) distributions in the optical multipolar planetary nebulae NGC 2440 and NGC 6302 are presented in this thesis. The observed CO J = 3-2 emission in NGC 2440 shows two major velocity components near the central region which are blue- and red-shifted by 18 km s^-1 relative to the systemic velocity of V_LSR = 43 km s^-1. The spatial distribution of CO emission shows two emission peaks at the systemic velocity which coincide well with the emission knots in the optical, suggesting that the CO outflow corresponds to one pair of the multiple optical bipolar lobes of the nebula. This particular pair of bipolar lobes seems distinctly rich in heavy molecules compared with the other optical bipolar lobes. The observed CO J = 3-2 emission in NGC 6302 also shows two major velocity components at the center which are blue- and red-shifted by 8 km s^-1 with respect to the systemic velocity of V_LSR = 30 km s^-1. The spatial distribution of CO emission shows three extended components at the systemic velocity, an extended component blueshifted by 12-46 km s^-1 with respect to the systemic velocity, an extended component redshifted by 30 km s^-1, and an extended component redshifted by 36-56 km s^-1. These extended components give us important insight into the interaction between the multiple flows and the AGB CSE.