Table 1



                     Off-peak                 Peak
Molecule       Observed     Model     Observed    Model

H2 ... 6.5 (21) ... 8.6 (22) H ... 1.4 (21) ... 1.9 (22) C+ < 2.4 (18) 5.1 (17) 9.0 (18) 6.9 (18) C 1.0 (17) 4.7 (16) 2.9 (17) 6.4 (17) CO 5.0 (17) 1.1 (18) 6.5 (18) 1.5 (19) C18O 1.0 (15) 8.9 (14) 1.3 (16) 1.2 (16) CS 1.5 (13) 2.7 (13) 1.5 (15) 3.7 (14) CN 8.0 (13) 3.8 (13) 4.0 (14) 5.1 (14) HCN 1.3 (13) 1.2 (13) 3.0 (14) 1.6 (14) HNC 5.0 (12) 2.7 (12) 6.0 (13) 3.7 (13) HCO+ 1.5 (13) 2.6 (12) 2.0 (14) 3.5 (13) H13CO ... 6.3 (10) 3.0 (12) 8.5 (11) H2CO 1.2 (13) 6.0 (12) 4.0 (14) 8.2 (13) C2H 3.0 (13) 3.6 (13) 1.3 (14) 4.9 (14) NO ... 1.3 (13) 1.5 (14) 1.8 (14) H2S 8.9 (12) 1.4 (11) 3.9 (14) 2.0 (12) SO < 2.5 (13) 1.5 (13) 6.0 (14) 2.0 (14) SO2 < 9.0 (11) 6.5 (11) 8.0 (12) 8.8 (12)