Presentation is loading. Please wait.

Presentation is loading. Please wait.

Orion-KL EVLA spectrum Karl Menten, Dec. 24, 2010 Received spectrum from R. Perley on Dec. 23, 2010 Frequency range 23654.50–24654.37 MHz Subtracted 2.2586.

Similar presentations


Presentation on theme: "Orion-KL EVLA spectrum Karl Menten, Dec. 24, 2010 Received spectrum from R. Perley on Dec. 23, 2010 Frequency range 23654.50–24654.37 MHz Subtracted 2.2586."— Presentation transcript:

1 Orion-KL EVLA spectrum Karl Menten, Dec. 24, 2010 Received spectrum from R. Perley on Dec. 23, 2010 Frequency range – MHz Subtracted MHz to frequencies so that NH 3 lines are centered at their rest frequencies. Scale was fixed by assuming an LSR velocity of ≈ +8 km/s (for the (J,K) = (1,1), (2,2),and (3,3) lines (Barrett et al. 1977, ApJ 211, L39) (Barrett et al. 1977, ApJ 211, L39) Comment: Data appear to be of very high quality. There are a few single channel spikes of intensity a few sigma increased noise level at frequencies higher than 24.5 GHz

2 Line content of spectrum Detect total of 13 “strong”(insh) lines 11 previously detected in ISM, listed on Lovas’ website: Dominated by lines from ammonia (NH 3 ) 5 lowest meta-stable inversion transitions (J,K) = (1,1), (2,2), (3,3), (4,4), and (5,5) non-meta-stable (9,8) and (10,9) lines (6,6) line from 15 NH 3 isotopologue, [ 14 N/ 15 N]≈250 2(0,2)-1(0,1) E/A doublet of methyl formate CH3CHO OCS Unidentified lines There certainly are (unidentified, but possiby identifiable) weaker lines in the spectrum

3 Line rest frequencies ( 5) NH3 9(8)-9(8) ( 1) NH3 1(1)-1(1) F,F1=3/2,1-5/2, ( 1) NH3 1(1)-1(1) F,F1=1/2,1-3/2, ( 1) NH3 1(1)-1(1) F,F1=5/2,2-5/2, ( 1) NH3 1(1)-1(1) F,F1=3/2,2-3/2, ( 2) NH3 1(1)-1(1) F,F1=1/2,0-1/2, ( 5) NH3 2(2)-2(2) F1= ( 5) NH3 2(2)-2(2) F1= ( 1) NH3 2(2)-2(2) F1= ( 5) NH3 2(2)-2(2) F1= ( 5) NH3 2(2)-2(2) F1= ( 5) NH3 3(3)-3(3) F1= ( 5) NH3 3(3)-3(3) F1= ( 1) NH3 3(3)-3(3) F1= ( 5) NH3 3(3)-3(3) F1= ( 5) NH3 3(3)-3(3) F1= ( 2) 15NH3 6(6)-6(6) Unidentified Unidentified ( 1) NH3 4(4)-4(4) ( 5) NH3 10(9)-10(9) *( 8) CH3OCHO 2(0,2)-1(0,1) E *( 8) CH3OCHO 2(0,2)-1(0,1) A ( 1) OCS ( 1) NH3 5(5)-5(5) Meta-stable NH3 lines have 5 main groups of hyperfine structure components which are blended in Orion-KL spectrum

4

5

6


Download ppt "Orion-KL EVLA spectrum Karl Menten, Dec. 24, 2010 Received spectrum from R. Perley on Dec. 23, 2010 Frequency range 23654.50–24654.37 MHz Subtracted 2.2586."

Similar presentations


Ads by Google