Alexander Petrov

Communication: Theoretical study of ThO for the electron electric dipole moment search

An experiment to search for the electron electric dipole moment (eEDM) on the metastable H(3)Δ1 state of ThO molecule was proposed and now prepared by the ACME Collaboration [http://www.electronedm.org]. To interpret the experiment in terms of eEDM and dimensionless constant kT, P characterizing the strength of the T,P-odd pseudoscalar-scalar electron-nucleus neutral current interaction, an accurate theoretical study of an effective electric field on electron, Eeff, and a parameter of the T,P-odd pseudoscalar-scalar interaction, WT, P, in ThO is required. We report our results for Eeff (84 GV/cm) and WT, P (116 kHz) together with the hyperfine structure constant, molecule frame dipole moment, and H(3)Δ1 → X(1)Σ(+) transition energy, which can serve as a measure of reliability of the obtained Eeff and WT, P values. Besides, our results include a parity assignment and evaluation of the electric-field dependence for the magnetic g factors in the Ω-doublets of H(3)Δ1.

Broadband velocity modulation spectroscopy of HfF + : towards a measurement of the electron electric dipole moment

Precision spectroscopy of trapped HfF + will be used in a search for the permanent electric dipole moment of the electron (eEDM). While this dipole moment has yet to be observed, various extensions to the standard model of particle physics (such as supersymmetry) predict values that are close to the current limit. We present extensive survey spectroscopy of 19 bands covering nearly 5000 cm −1 using both frequency-comb and single-frequency laser velocity-modulation spectroscopy. We obtain high-precision rovibrational constants for eight electronic states inclu ding those that will be necessary for state preparation and r eadout in an actual eEDM experiment.

Collision-Induced Processes in Iodine Molecule

The chapter outlines different types of exchange of translational, rotational, vibrational and electronic energies of diatomic molecules. Then, rotational, vibrational, rovibrational collision-induced processes in the I2(( B{0}_u^{+} )) state, as well as B state collision-induced predissociation are briefly examined. The principal attention is given to nonadiabatic transitions between IP states of the second, and, especially, the first tiers induced by collisions with rare gas atoms and molecules possessing permanent electric quadrupole and dipole moments as well as transition electric dipole moments. Overview of theoretical models and experimental methods is also done.

Electronic States of Iodine Molecule and Optical Transitions Between Them

The chapter outlines arrays of the valence, ion-pair (IP) and Rydberg states of the iodine molecule. At the outset, a molecular orbital theory used for descriptions of the valence and IP states, pure precession model utilized for the IP states, and the describing of the Rydberg states are defined. Then, the valence states and valence-valence transitions, as well as the IP states and IP – valence transitions are described in details. Data given in this Chapter will be used for descriptions of intra- and intermolecular perturbation described in Chaps. 4, 5 and 6.

Van der Waals Complexes of Iodine Molecules

The chapter deals with optically populated RgI2(( X{0}_g^{+},B{0}_u^{+} ) and IP) vdW complexes . Overview of experimental methods used as well as detailed description of design and characteristics of the set-up utilized supersonic molecular beam technique created in the author’s group are carried out. Survey of experimental and theoretical works devoted to studies of vdW complexes of T-shaped , linear and free-rotor configurations are performed. The particular attention has been given to RgI2(IP) vdW complexes.

Intramolecular Perturbations in the Electronically Excited States

The chapter deals with intramolecular perturbations in the valence, ion-pair, and Rydberg states. In the beginning, theoretical descriptions of the hyperfine interactions and nonadiabatic heterogeneous as well as two-state perturbation model are briefly described. Then, spontaneous predissociation of the valence and Rydberg state is briefly considered. The emphasis is on hyperfine interactions and heterogeneous perturbation of bound, valence, ion-pair, as well as homogeneous and heterogeneous perturbation between the ion-pair and Rydberg states.

Overview of Instrumentation and Methods

As it shown in Chap. 1, molecular iodine is very interesting subject for scientists working in the fields of molecular spectroscopy and chemical physics. Absorption of this molecules has been recorded in wide spectral range, from near IR, λ ≈ 1350 nm, to vacuum ultraviolet (VUV), λ ≈ 105 nm, (see [1–3] and references). To study this molecule, classical, absorption measurements, detection of subsequent spontaneous luminescence and photodecay as well as up to date methods have been utilized. In this chapter, classical methods are considered briefly, whereas contemporary methods of studies are discussed more substantially.