High-resolution storage-ring measurements of the dissociative recombination of H{sub 3}{sup +} using a supersonic expansion ion source

Journal Article · Fri Oct 15 00:00:00 EDT 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.042715· OSTI ID:21450783

Kreckel, Holger; Crabtree, Kyle N; Tom, Brian A ^[1]; Novotny, Oldrich; Lestinsky, Michael ^[2]; Buhr, Henrik ^[3]; Petrignani, Annemieke; Berg, Max H; Bing, Dennis; Grieser, Manfred; Krantz, Claude; Mendes, Mario B; Nordhorn, Christian; Repnow, Roland; Stuetzel, Julia; Wolf, Andreas ^[4]; Thomas, Richard D ^[5]; McCall, Benjamin J ^[1]

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1. Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
2. Columbia Astrophysics Laboratory, 550 West 120th Street, New York, New York 10027 (United States)
3. Faculty of Physics, Weizmann Institute of Science, Rehovot 76100 (Israel)
4. Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, D-69117 Heidelberg (Germany)
5. Department of Physics, Stockholm University, Alba Nova, S-106 91 Stockholm (Sweden)

We have performed measurements of the dissociative electron recombination (DR) of H{sub 3}{sup +} at the ion storage ring TSR utilizing a supersonic expansion ion source. The ion source has been characterized by continuous wave cavity ring-down spectroscopy. We present high-resolution DR rate coefficients for different nuclear spin modifications of H{sub 3}{sup +} combined with precise fragment imaging studies of the internal excitation of the H{sub 3}{sup +} ions inside the storage ring. The measurements resolve changes in the energy dependence between the ortho-H{sub 3}{sup +} and para-H{sub 3}{sup +} rate coefficients at low center-of-mass collision energies. Analysis of the imaging data indicates that the stored H{sub 3}{sup +} ions may have higher rotational temperatures than previously assumed, most likely due to collisional heating during the extraction of the ions from the ion source. Simulations of the ion extraction shed light on possible origins of the heating process and how to avoid it in future experiments.

• OSTI ID: 21450783
• Journal Information: Physical Review. A, Vol. 82, Issue 4; Other Information: DOI: 10.1103/PhysRevA.82.042715; (c) 2010 The American Physical Society; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
COLLISIONAL HEATING
COMPUTERIZED SIMULATION
ELECTRONS
ENERGY DEPENDENCE
EXCITATION
EXPANSION
HYDROGEN IONS 3 PLUS
ION COLLISIONS
ION SOURCES
ION SPECTROSCOPY
RECOMBINATION
RESOLUTION
SPIN
STORAGE RINGS
ANGULAR MOMENTUM
CATIONS
CHARGED PARTICLES
COLLISIONS
ELEMENTARY PARTICLES
ENERGY-LEVEL TRANSITIONS
FERMIONS
HEATING
HIGH-FREQUENCY HEATING
HYDROGEN IONS
IONS
LEPTONS
MAGNETIC-PUMPING HEATING
MOLECULAR IONS
PARTICLE PROPERTIES
PLASMA HEATING
SIMULATION
SPECTROSCOPY