The fine and Hyperfine structure of fermionic levels in gravitational fields

We investigate single-particle energy spectra of the hydroxyl free radical (OH) in the lowest electronic and rovibrational level under combined static electric and magnetic fields, as an example of heteronuclear polar diatomic molecules. In addition to the fine-structure interactions, the hyperfine interactions and centrifugal distortion effects are taken into account to yield the zero-field spectrum of the lowest 2 Π 3 / 2 manifold to an accuracy of less than 2 kHz. We also examine level crossings and repulsions in the hyperfine structure induced by applied electric and magnetic fields. Compared to previous work, we found more than 10% reduction of the magnetic fields at level repulsions in the Zeeman spectrum subjected to a perpendicular electric field. In addition, we find new level repulsions, which we call Stark-induced hyperfine level repulsions, that require both an electric field and hyperfine structure. It is important to take into account hyperfine structure when we investigate physics of OH molecules at micro-Kelvin temperatures and below.We investigate single-particle energy spectra of the hydroxyl free radical (OH) in the lowest electronic and rovibrational level under combined static electric and magnetic fields, as an example of heteronuclear polar diatomic molecules. In addition to the fine-structure interactions, the hyperfine interactions and centrifugal distortion effects are taken into account to yield the zero-field spectrum of the lowest 2 Π 3 / 2 manifold to an accuracy of less than 2 kHz. We also examine level crossings and repulsions in the hyperfine structure induced by applied electric and magnetic fields. Compared to previous work, we found more than 10% reduction of the magnetic fields at level repulsions in the Zeeman spectrum subjected to a perpendicular electric field. In addition, we find new level repulsions, which we call Stark-induced hyperfine level repulsions, that require both an electric field and hyperfine structure. It is important to take into account hyperfine structure when we investigate physics of OH molecules at micro-Kelvin temperatures and below.

arXiv:1410.3849New Journal of PhysicsApr 22, 201531 citations

The pressure of fermions with gravitational interaction

Joachim A. Messer

The European Physical Journal BSep 1, 19798 citations

Hyperfine structure of extremely high Rydberg msns1S0and msns3S1series in odd alkaline-earth isotopes

Jun-Qiang Sun, K. T. Lu

In extremely high Rydberg states of odd alkaline-earth isotopes, the Fermi constant a ms is comparable to the energy separation between levels belonging to different principal quantum numbers n and hyperfine interactions dominate the structure of the levels. The multichannel quantum defect theory of fine structure has been developed and applied to hyperfine structure and thus the HFS can be analysed directly by MQDT. A two-channel quantum defect model for extremely high Rydberg msns 1 S 0 and msns 3 S 1 series in odd alkaline-earth isotopes for F=I is described. The U i(F)i matrix is given analytically and the relationship between the eigenquantum defects of HFS and the quantum defects of fine structure is derived. The HFS of two extremely high Rydberg 5sns 1 S 0 and 3 S 1 series in 87 Sr has been calculated by the model and an excellent agreement between the theoretical and experimental results has been achieved. The HFS of extremely high Rydberg msns 1 S 0 and 3 S 1 series in 43 Ca, 135 Ba and 137 Ba are also analysed by the model.In extremely high Rydberg states of odd alkaline-earth isotopes, the Fermi constant a ms is comparable to the energy separation between levels belonging to different principal quantum numbers n and hyperfine interactions dominate the structure of the levels. The multichannel quantum defect theory of fine structure has been developed and applied to hyperfine structure and thus the HFS can be analysed directly by MQDT. A two-channel quantum defect model for extremely high Rydberg msns 1 S 0 and msns 3 S 1 series in odd alkaline-earth isotopes for F=I is described. The U i(F)i matrix is given analytically and the relationship between the eigenquantum defects of HFS and the quantum defects of fine structure is derived. The HFS of two extremely high Rydberg 5sns 1 S 0 and 3 S 1 series in 87 Sr has been calculated by the model and an excellent agreement between the theoretical and experimental results has been achieved. The HFS of extremely high Rydberg msns 1 S 0 and 3 S 1 series in 43 Ca, 135 Ba and 137 Ba are also analysed by the model.

Journal of Physics B Atomic Molecular and Optical PhysicsJun 14, 198814 citations

Thermodynamics of trapped fermions in gravitational field

Igor K. Kulikov

Physics Letters AJul 1, 20011 citation

Fine and hyperfine splitting of the low-lying states of Be9

Mariusz Puchalski, Jacek Komasa, Krzysztof Pachucki

We perform accurate calculations of energy levels as well as fine and hyperfine splittings of the lowest $^{1,3}P_{J}, ^{3}S_{1}, ^{3}P_{J}^{e}$ , and $^{1,3}D_{J}$ excited states of the $^{9}\mathrm{Be}$ atom using explicitly correlated Gaussian functions, and we report on the breakdown of the standard hyperfine structure theory. Because of the strong hyperfine mixing, which prevents the use of common hyperfine constants, we formulate a description of the fine and hyperfine structure that is valid for an arbitrary coupling strength and may have wide applications in many other atomic systems.We perform accurate calculations of energy levels as well as fine and hyperfine splittings of the lowest $^{1,3}P_{J}, ^{3}S_{1}, ^{3}P_{J}^{e}$, and $^{1,3}D_{J}$ excited states of the $^{9}\mathrm{Be}$ atom using explicitly correlated Gaussian functions, and we report on the breakdown of the standard hyperfine structure theory. Because of the strong hyperfine mixing, which prevents the use of common hyperfine constants, we formulate a description of the fine and hyperfine structure that is valid for an arbitrary coupling strength and may have wide applications in many other atomic systems.

arXiv:2106.16161Physical Review AAug 31, 202112 citations

We perform accurate calculations of energy levels as well as fine and hyperfine splittings of the lowest

^{1,3}P_{J}, ^{3}S_{1}, ^{3}P_{J}^{e}

, and

^{1,3}D_{J}

excited states of the

^{9}\mathrm{Be}

atom using explicitly correlated Gaussian functions, and we report on the breakdown of the standard hyperfine structure theory. Because of the strong hyperfine mixing, which prevents the use of common hyperfine constants, we formulate a description of the fine and hyperfine structure that is valid for an arbitrary coupling strength and may have wide applications in many other atomic systems.