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Helium Pressure Shift of the Hyperfine Clock Transition in Hg-201(+)There are two stable odd isotopes of mercury with singly ionized hyperfine structure suitable for a microwave atomic clock: Hg-199(+) and Hg-201(+). We are investigating the viability of a trapped ion clock based on Hg-201(+) in a configuration that uses a buffer gas to increase ion loading efficiency and counter ion heating from rf trapping fields. Traditionally, either helium or neon is used as the buffer gas at approx. 10(exp -5) torr to confine mercury ions near room temperature. In addition to the buffer gas, other residual background gasses such as H2O, N2, O2, CO, CO2, and CH2 may be present in trace quantities. Collisions between trapped ions and buffer gas or background gas atoms/molecules produce a momentary shift of the ion clock transition frequency and constitute one of the largest systematic effects in this type of clock. Here we report an initial measurement of the He pressure shift in Hg-201(+) and compare this to Hg-199(+).
Document ID
20150008512
Document Type
Conference Paper
External Source(s)
Authors
Larigani, S. Taghavi (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Burt, E. A. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Tjoelker, R. L. (Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Date Acquired
May 20, 2015
Publication Date
June 2, 2010
Subject Category
Atomic and Molecular Physics
Meeting Information
2010 IEEE International Frequency Control Symposium(Newport Beach, CA)
Distribution Limits
Public
Copyright
Other