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Direct measurement of the fine-structure interval and g_J factors of singly ionized atomic carbon by laser magnetic resonance

Cooksy, Andrew L. and Blake, Geoffrey A. and Saykally, Richard J. (1986) Direct measurement of the fine-structure interval and g_J factors of singly ionized atomic carbon by laser magnetic resonance. Astrophysical Journal Letters, 305 (2). L89-L92. ISSN 2041-8205. doi:10.1086/184691.

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We present the results of laser magnetic resonance measurements performed on the ground ^2P state of singly ionized atomic carbon (C_II). The 2^P_(3/2) ← ^2P_(1/2) fine-structure intervals of both ^(12)C^+ and ^(13)C^+ have been determined with a precision of approximately 1 ppm, and the g_J factors to approximately one part in 10^4. Specifically, we find that g_(J=(1/2)) = 0.66576(11) and g_(J=(3/2)) = 1.33412(11), while for ^(12)C^+ ΔE_0(^2P_(3/2) ← ^2P_(1/2))= 1900536.9(1.3) MHz, with ΔE_0(^2P_(3/2) ← ^2P_(1/2)) = 1900545.8(2.1) and ΔE(^2P(3/2) ← ^2P_(1/2), F = 2 ← 1) = 1900466.1(2.3) MHz in ^(13)C^+. The highly precise values of the ^(12)C_II and ^(13)C_II fine-structure intervals verify the already secure far-infrared astronomical identification of C^+ and should allow the interstellar (^(12)C / ^(13)C) ratio to be unambiguously determined in a number of environments.

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Blake, Geoffrey A.0000-0003-0787-1610
Additional Information:© 1986 American Astronomical Society. Received 1986 February 3; accepted 1986 March 12. This work was supported by the National Science Foundation, Structure and Thermodynamics Program (grant CHE 8402861). A. Cooksy thanks Chevron for a graduate fellowship, and G. Blake and R. Saykally gratefully acknowledge financial support provided by the Berkeley Miller Research Institute.
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Miller Institute for Basic Research in ScienceUNSPECIFIED
Subject Keywords:laboratory spectra; line identification; molecular processes; carbon isotopes; gas ionization; interstellar gas; laser applications; line spectra; magnetic resonance; abundance; far infrared radiation; least squares method; molecular clouds; zeeman effect
Issue or Number:2
Record Number:CaltechAUTHORS:20120913-112214142
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:34064
Deposited On:13 Sep 2012 18:47
Last Modified:09 Nov 2021 23:06

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