12–17 Jun 2016
University of Ottawa
America/Toronto timezone
Welcome to the 2016 CAP Congress! / Bienvenue au congrès de l'ACP 2016!

Tune-out Wavelengths and Polarizability for the Helium $\mathbf{1s2s}\;\mathbf{^{3}}$S State.$^*$

13 Jun 2016, 11:30
15m
SITE G0103 (University of Ottawa)

SITE G0103

University of Ottawa

SITE Building, 800 King Edward Ave, Ottawa, ON
Oral (Student, Not in Competition) / Orale (Étudiant(e), pas dans la compétition) Division of Atomic, Molecular and Optical Physics, Canada / Division de la physique atomique, moléculaire et photonique, Canada (DAMOPC-DPAMPC) M1-7 Atomic and Molecular Spectroscopy and Precision Measurements I (DAMOPC) / Spectroscopie atomique et moléculaire et mesures de précision I (DPAMPC)

Speaker

Mr Jacob Manalo (University of Windsor)

Description

This paper is part of a joint theoretical/experimental project to test QED by measuring the tune-out wavelength of helium near the 413 nm line where the frequency-dependent polarizability vanishes [1]. As a first strep, we calculate a high-precision value for the static polarizability defined in the nonrelativistic limit as the second-order perturbation energy due to the perturbation $V=eFr\cos{\theta}$ where $F$ is the electric field strength. For a two electron atom such as helium, high precision results are obtained by use of an explicitly correlated Hylleraas basis set to represent the complete set of intermediate states. We also include for the first time relativistic corrections due to the Breit interaction terms proportional to $p_1^4+p_2^4$, $\delta(r_{12})$, $\delta(r_1)$ and the orbit-orbit interaction [2]. For the $2$ $^3S$ state of helium, we find a relativistic contribution to the polarizability with finite nuclear mass corrections included of $-0.098\,765770(9)$ $a_0^3$ atomic units, where $\alpha$ is the fine structure constant.\\[0pt] [1] B.M. Henson et al. Phys.\ Rev.\ Lett.\ {\bf 115}, 043004 (2015).\newline [2] K. Pachucki and J. Sapirstein, Phys. Rev. A \textbf{63}, 012504, (2000).\newline $^*$Research supported by NSERC.

Primary author

Mr Jacob Manalo (University of Windsor)

Co-author

Dr Gordon Drake (University of Windsor)

Presentation materials