Collinear laser spectroscopy of francium using online rubidium vapor neutralization and amplitude modulated lasers

Journal Article · Tue Dec 15 00:00:00 EST 2009 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.3271037· OSTI ID:22051108

Sell, J F; Gulyuz, K; Sprouse, G D ^[1]

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1. Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794 (United States)

Performing collinear laser spectroscopy on low intensity radioactive beams requires sensitive detection techniques. We explain our apparatus to detect atomic resonances in neutralized {sup 208-210}Fr ion beams at beam energies of 5 keV and intensities of 10{sup 5} s{sup -1}. Efficient neutralization ({>=}80%) is accomplished by passing the beam through a dense Rb vapor. Increased detection efficiency is achieved by amplitude modulating the exciting laser to decrease the scattered light background, allowing fluorescence detection only when the laser is near its minimum in the modulation cycle. Using this technique in a collinear geometry we achieve a background reduction by a factor of 180 and a signal-to-noise increase of 2.2, with the lifetime of the atomic state playing a role in the efficiency of this process. Such laser modulation will also produce sidebands on the atomic spectra which we illustrate.

• OSTI ID: 22051108
• Journal Information: Review of Scientific Instruments, Vol. 80, Issue 12; Other Information: (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
EFFICIENCY
ELECTRONIC STRUCTURE
ENERGY LEVELS
FLUORESCENCE
FRANCIUM
FRANCIUM 210
FRANCIUM IONS
ION BEAMS
KEV RANGE
LASER RADIATION
LASER SPECTROSCOPY
LIFETIME
MODULATION
PHOTON-ATOM COLLISIONS
RESONANCE
RUBIDIUM
VAPORS
VISIBLE RADIATION