Nivedya Valappol

Determination of transition frequencies in a single Ba-138(+) ion

Transition frequencies between low-lying energy levels in a single trapped Ba-138(+) ion have been measured with laser spectroscopy referenced to an optical frequency comb. By extracting the frequencies of one-photon and two-photon components of the line shape using an eight-level optical Bloch model, we achieved 0.1 MHz accuracy for the 5d D-2(3/2)-6p P-2(1/2) and 6s S-2(1/2)-5d D-2(3/2) transition frequencies, and 0.2MHz for the 6s S-2(1/2)-6p P-2(1/2) transition frequency.

Precision Tests of Discrete Symmetries at Low Energies

Low energy precision measurements provide for precise testing of the Standard Model, e.g., in searches for violations of the discrete symmetries charge conjugation (C), parity (P), and time reversal (T) as well as their combinations CP and CPT. We focus here on new experiments concerning atomic parity violation (APV) and searches for a permanent electric dipole moment (EDM) in atoms. In particular, we address precision APV experiments on Ba+ and Ra+ single ions that will enable the extraction of the Weinberg angle at lowest presently accessible momentum transfer. They are expected to contribute towards searches for new particles such as dark Z-bosons. We also review experimental programmes in which an EDM is searched for and we compare them in a common framework. We describe latest EDM searches in heavy effective two-electron atoms such as Xe and Hg. We also indicate possible future prospects of searches for a permanent EDM of the electron using molecules with large enhancement factors.

Lifetime measurement of the 5d2 D 5/2 state in Ba+

The lifetime of the metastable 5d2D5/2 state has been measured for a single trapped Ba+ ion in a Paul trap in Ultra High Vacuum (UHV) in the 10−10 mbar pressure range. A total of 5046 individual periods when the ion was shelved in this state have been recorded. A preliminary value τD5/2=26.4(1.7)

Lifetime measurement of the 5d2D5/2 state in Ba+

\tau _{D_{5/2}} = 26.4(1.7)

Lifetime measurement of the 5d ^2D5/2 state in Ba+

s is obtained through extrapolation to zero residual gas pressure.

Ba+ Isotope shift studies in preparation of atomic parity violation measurement

The lifetime of the metastable 5d2D5/2 state has been measured for a single trapped Ba+ ion in a Paul trap in Ultra High Vacuum (UHV) in the 10−10 mbar pressure range. A total of 5046 individual periods when the ion was shelved in this state have been recorded. A preliminary value τD5/2=26.4(1.7)

Precision Spectroscopy of Ba+ Isotopes in a Paul Trap

\tau _{D_{5/2}} = 26.4(1.7)

Light Shifts to determine atomic properties of 138Ba+ ions for measuring atomic parity violation

s is obtained through extrapolation to zero residual gas pressure.

Alkali Earth Ion Spectroscopy in Preparation of a Weinberg Angle Measurement

The lifetime of the metastable 5d2D5/2 state has been measured for a single trapped Ba+ ion in a Paul trap in Ultra High Vacuum (UHV) in the 10−10 mbar pressure range. A total of 5046 individual periods when the ion was shelved in this state have been recorded. A preliminary value τD5/2=26.4(1.7)

Precision determination of properties of 138Ba+ ion

\tau _{D_{5/2}} = 26.4(1.7)