further studies of λ 5797.1 diffuse interstellar band takeshi oka, lew m. hobbs, daniel e. welty,...
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Further studies of λ 5797.1 Diffuse Interstellar Band
Takeshi Oka, Lew M. Hobbs, Daniel E. Welty, Donald G. York Department of Astronomy and Astrophysics,
University of Chicago
Julie DahlstromDepartment of Physics and Astronomy
Carthage College
Adolf N. WittDepartment of Physics and Astronomy
University of Toledo
June 25, 2015, International Symposium on Molecular Spectroscopy, University of Illinois at Urbana Champaign
The Diffuse Interstellar Bands (DIBs)
Ben McCall
Don York Apache point observatory
414 bands
380 bands
Two contrasting sightlines, C2 C3 rich and poor
HD 204827 Highest N(C2) and N(C3)
HD 183143 C2, C3 not detected
Our previous work on λ 5797.1 DIB x-axis Stars ~ 300 (SDSS > 5000)y-axis DIBs ~ 500
Herschel 36λ 5797 DIB
From Don YorkOctober 8, 2011
Her 38 rotational excitationhigh Tr ~ 90 KB´ ‒ B < 0linear molecule
polar molecule n ≤ 7
Polar moleculeParallel band of prolate topTr = 2.73 K
5 ≤ n ≤ 7
AAT R ~ 600,000
Vibronic satellites of λ 5797.1 DIB
5797.2HD 183143 73 DIBs
HD 204827 120 DIBs
5545.15494.25797.1 Å17250.12 cm-1
Correlations between DIBs
×
×
0.943 (77)
0.941 (77)
0.903 (109)
Vibronic bands
1147 cm-1
602 cm-1
5797.1 Å17250.12 cm-1
5545.1 Å18034.1 cm-1
5494.1 Å18201.3 cm-1
784.0cm-1
951.2 cm-1
Correlations: 5797.1 vs 5494 and 5545
r = 0.941 77 starsr = 0.943 77 stars
HD 21389HD 229059
Hobbs et al. (2009)
Line shape
ESO LaSilla 3.6-m telescopeR = 115,000
II. 5797 DIB and RR 5800 by the same molecule
Emission and Absorption
Herschel 36 Tr ~ 90 K
Red Rectangle 3000 K
Draine, Ann. Rev. Astron. Astrophys. 41, 241 (2003)
III Anomalous microwave emission
A&A 565, A103 (2014)
ApJ 460, 1 (1996)
I am scared and mystified
High column density 1013 cm-2
Snow & McCall, ARAA, 44, 367 (2004)
PAH C60
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