Gas-phase shock chemistry of the young bipolar outflow L1157

摘要

We have studied the production of the key observed species in the bipolar outflow L1157. This is carried out using two-fluid MHD of C-type shocks propagating in a molecular cloud model of density 10~4 cm~(-3) with shock speeds of 10 ≤ V_s ≤ 25 km s~(-1) and the magnetic induction 20 ≤ B ≤ 200 μG. Using an extensive chemical network with the most updating reaction rates, the main results show that the calculated fractional abundances is in agreement with observation assuming shock velocity V_s = 20 km s~(-1) and magnetic induction B = 22 μG.