BIMA Array Detections of HCN in Comets

BIMA Array Detections of HCN in Comets
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This article features the collaboration of various universities and organizations to detect HCN in comets using the BIMA Array. The article also mentions the 60th International Symposium on Molecular Spectroscopy.

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PowerPoint presentation about 'BIMA Array Detections of HCN in Comets'. This presentation describes the topic on This article features the collaboration of various universities and organizations to detect HCN in comets using the BIMA Array. The article also mentions the 60th International Symposium on Molecular Spectroscopy.. The key topics included in this slideshow are BIMA Array, HCN detection, comets, collaboration, molecular spectroscopy,. Download this presentation absolutely free.

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1. BIMA Array BIMA Array Detections of HCN in Comets Detections of HCN in Comets LINEAR (C/2002 T7) LINEAR (C/2002 T7) and and NEAT (C/2001 Q4) NEAT (C/2001 Q4) D. N. Friedel (University of Illinois) D. N. Friedel (University of Illinois) Collaborators: Collaborators: A. Remijan (NASA GSFC) A. Remijan (NASA GSFC) L. E. Snyder, H. R. Dickel, L.W. Looney (University of Illinois) L. E. Snyder, H. R. Dickel, L.W. Looney (University of Illinois) M. F. A'Hearn (University of Maryland) M. F. A'Hearn (University of Maryland) I. De Pater, J. R. Forster, C. Kraybill, M. C. H. Wright (University of California, Berkeley) I. De Pater, J. R. Forster, C. Kraybill, M. C. H. Wright (University of California, Berkeley) M. R. Hogerheijde (Leiden Observatory) M. R. Hogerheijde (Leiden Observatory) P. Palmer (University of Chicago) P. Palmer (University of Chicago) G. A. Blake (Caltech) G. A. Blake (Caltech) Adam Block/NOAO/AURA/NSF Adam Block/NOAO/AURA/NSF Svend and Carl Freytag/Adam Block/ Svend and Carl Freytag/Adam Block/ NOAO/AURA/NSF NOAO/AURA/NSF 60 th International Symposium on Molecular Spectroscopy 60 th International Symposium on Molecular Spectroscopy

2. Coordinates (J2000) and Synthesized Beams Coordinates (J2000) and Synthesized Beams Observation Dates and Distances Observation Dates and Distances Spectral resolution: 98-391 kHz chan -1 (0.3 - 1.4 km s -1 chan -1 ) Spectral resolution: 98-391 kHz chan -1 (0.3 - 1.4 km s -1 chan -1 ) (1 AU ~ cm) Observations Observations ~18x15 ~18x15 ~ 34:00 ~ 34:00 ~09:07 ~09:07 NEAT NEAT ~26x19 ~26x19 ~ -09:30 ~ -09:30 ~01:40 ~01:40 LINEAR LINEAR ~0.55-0.61 AU ~0.55-0.61 AU r h ~0.97 AU r h ~0.97 AU 2004 May 20-24 2004 May 20-24 NEAT NEAT ~0.32-0.44 AU ~0.32-0.44 AU r h ~0.73-77 AU r h ~0.73-77 AU 2004 May 11-15 2004 May 11-15 LINEAR LINEAR

3. Transitions Transitions

4. The VTOV Model The VTOV Model V ariable T emperature and O utflow V elocity V ariable T emperature and O utflow V elocity From Combi, et al. 1999, ApJ, 512, 961 Haser model assumes constant temperature and outflow velocity Haser model assumes constant temperature and outflow velocity This is not the case for higher resolution interferometric observations This is not the case for higher resolution interferometric observations Models the comet as shells Models the comet as shells Temperature and outflow velocity assigned to each shell Temperature and outflow velocity assigned to each shell Model array response to each shell Model array response to each shell

5. NEAT NEAT LINEAR LINEAR 4.6(1.5) 4.6(1.5) 0.33(0.11)% 0.33(0.11)% 6.5(2.2)x10 26 6.5(2.2)x10 26 6.4(2.1)x10 12 6.4(2.1)x10 12 LINEAR LINEAR 0.3(0.2) 0.3(0.2) 0.07(0.04)% 0.07(0.04)% 8.9(4.7)x10 25 8.9(4.7)x10 25 8.5(4.5)x10 11 8.5(4.5)x10 11 NEAT NEAT HCN / CN HCN / CN HCN / H 2 O HCN / H 2 O Q p (s -1 ) Q p (s -1 ) N (cm -2 ) N (cm -2 ) HCN J =1-0 HCN J =1-0

6. 3.8(0.8)% 3.8(0.8)% 7.5(1.7)x10 27 7.5(1.7)x10 27 1.4(0.3)x10 14 1.4(0.3)x10 14 LINEAR LINEAR 2.4(1.4)% 2.4(1.4)% 2.9(1.7)x10 27 2.9(1.7)x10 27 4.6(2.7)x10 13 4.6(2.7)x10 13 NEAT NEAT CH 3 OH / H 2 O CH 3 OH / H 2 O Q p (s -1 ) Q p (s -1 ) N (cm -2 ) N (cm -2 ) CH 3 OH J =3 1,3 -4 0,4 A+ CH 3 OH J =3 1,3 -4 0,4 A+ 0.04(0.01)% 0.04(0.01)% 8.7(3.0)x10 26 8.7(3.0)x10 26 2.3(0.6)x10 12 2.3(0.6)x10 12 LINEAR LINEAR <0.002% <0.002% <2.1x10 24 <2.1x10 24 <3.5x10 11 <3.5x10 11 NEAT NEAT CS / H 2 O CS / H 2 O Q p (s -1 ) Q p (s -1 ) N (cm -2 ) N (cm -2 ) CS J =2-1 CS J =2-1 NEAT LINEAR

7. Non-Detections Non-Detections Based on 1 rms noise level and single channel width Based on 1 rms noise level and single channel width Continuum at 89 GHz Continuum at 89 GHz LINEAR <9 mJy beam -1 LINEAR <9 mJy beam -1 NEAT <1 mJy beam -1 NEAT <1 mJy beam -1

8. Conclusions Conclusions Used VTOV Model to calculate Q and N Used VTOV Model to calculate Q and N LINEAR LINEAR HCN/H 2 O similar to Hale-Bopp HCN/H 2 O similar to Hale-Bopp CH 3 OH/H 2 O similar to Hale-Bopp CH 3 OH/H 2 O similar to Hale-Bopp CS/H 2 O similar to Hyakutake and LINEAR (C/1999 B2) CS/H 2 O similar to Hyakutake and LINEAR (C/1999 B2) HNC/HCN <2.2% HNC/HCN <2.2% NEAT NEAT HCN/H 2 O similar to Hyakutake HCN/H 2 O similar to Hyakutake CH 3 OH/H 2 O between Hale-Bopp and Hyakutake CH 3 OH/H 2 O between Hale-Bopp and Hyakutake