Parity and time invariance violating forces produce collective P-and T-odd moments in nuclei with... more Parity and time invariance violating forces produce collective P-and T-odd moments in nuclei with static octupole deformation. Collective Schiff moment, electric octupole and dipole and also magnetic quadrupole appear due to the mixing of rotational levels of opposite parity and can exceed singleparticle moments by more than a factor of 100. This enhancement is due to two factors, the collective nature of the intrinsic moments and the small energy separation between members of parity doublets. The above moments induce T-and P-odd effects in atoms and molecules. Experiments with such systems may improve substantially the limits on time reversal violation.
The charge density of vector particles, for example W ± , may change sign. The effect manifests i... more The charge density of vector particles, for example W ± , may change sign. The effect manifests itself even for a free propagation; when the energy of the W-boson satisfies ε > √ 2m and the standing-wave is considered the charge density oscillates in space. The charge density of W also changes sign in a close vicinity of a Coulomb center. The dependence of this effect on the g-factor for an arbitrary vector boson, for example ρ-meson , is discussed. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles. Their contributions to the current have a polarization nature. The charge density of this current, ρ Pol = −∇ • P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction, oscillates in space, producing zero contribution to the total charge.
A method to calculate the mean squared matrix element of weak interaction between compound states... more A method to calculate the mean squared matrix element of weak interaction between compound states is developed. The result is expressed in terms of matrix elements of the nucleon-nucleon strong and weak interactions times the Fermi distribution functions at finite temperature. Numerical calculations for 233 Th are in excellent agreement with recent measurements of parity nonconservation effects in neutron capture. In fact, our calculations prove that the factor of dynamical enhancement (ratio of compound-nucleus effect to single-particle one) really exceeds 100, thus making it unnesessary to assume a value of the weak constant bigger than standard one (g 10 8 ∼ 1 ÷ 4).
Scattering length, which can be measured in Bose-Einstein condensate and Feshbach molecule experi... more Scattering length, which can be measured in Bose-Einstein condensate and Feshbach molecule experiments, is extremely sensitive to the variation of fundamental constants, in particular, the electron-to-proton mass ratio (me/mp or me/ΛQCD, where ΛQCD is the QCD scale). Based on single-and two-channel scattering model, we show how the variation of the mass ratio propagates to the scattering length. Our results suggest that variation of me/mp on the level of 10 −11 ∼ 10 −14 can be detected near a narrow magnetic or an optical Feshbach resonance by monitoring the scattering length on the 1% level. Derived formulae may also be used to estimate the isotopic shift of the scattering length.
We describe the results of a search for time variability of the fine structure constant α using a... more We describe the results of a search for time variability of the fine structure constant α using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four independent samples, spanning ∼ 23% to 87% of the age of the universe. Each sample yields a smaller α in the past and the optical sample shows a 4σ deviation: ∆α/α = −0.72 ± 0.18 × 10 −5 over the redshift range 0.5 < z < 3.5. We find no systematic effects which can explain our results. The only potentially significant systematic effects push ∆α/α towards positive values, i.e. our results would become more significant were we to correct for them.
We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain ... more We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of the fine structure constant ␣ and (m q /⌳ QCD) from recent measurements of hydrogen hyperfine ͑21 cm͒ and molecular rotational transitions in quasar absorption systems, atomic clock experiments with hyperfine transitions in H, Rb, Cs, Yb ϩ , Hg ϩ , and optical transition in Hg ϩ. Experiments with Cd ϩ , deuterium/hydrogen, molecular SF 6 , and Zeeman transitions in 3 He/Xe are also discussed.
We consider the scalar-tensor theories of gravity extended by the pseudoscalar couplings to matte... more We consider the scalar-tensor theories of gravity extended by the pseudoscalar couplings to matter and gauge fields and derive constraints on the CP-odd combinations of scalar and pseudoscalar couplings from laboratory spin precession experiments and from the evolution of photon polarization over cosmological distances. We show the complimentary character of local and cosmological constraints, and derive novel bounds on the pseudoscalar couplings to photons from the laboratory experiments. It is also shown that the more accurate treatment of the spin content of nuclei used in the spin precession experiments allows to tighten bounds on Lorentz-violating backgrounds coupled to the proton spin.
Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis J. C. Bere... more Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis J. C. Berengut (a) , E. Epelbaum (b) , V. V. Flambaum (a) , C. Hanhart (c),(d),(e) , U.-G. Meißner (c),(d),(e),(f),(g),(h) , J. Nebreda (i) , and J. R. Peláez (j)
It is believed that there may have been a large number of black holes formed in the very early un... more It is believed that there may have been a large number of black holes formed in the very early universe. These would have quantised masses. A charged "elementary black hole" (with the minimum possible mass) can capture electrons, protons and other charged particles to form a "black hole atom". We find the spectrum of such an object with a view to laboratory and astronomical observation of them, and estimate the lifetime of the bound states. There is no limit to the charge of the black hole, which gives us the possibility of observing Z > 137 bound states and transitions at the lower continuum. Negatively charged black holes can capture protons. For Z > 1, the orbiting protons will coalesce to form a nucleus (after β-decay of some protons to neutrons), with a stability curve different to that of free nuclei. In this system there is also the distinct possibility of single quark capture. This leads to the formation of a coloured black hole that plays the role of an extremely heavy quark interacting strongly with the other two quarks. Finally we consider atoms formed with much larger black holes.
ABSTRACT We calculate the 6s-7s parity nonconserving (PNC) E1 transition amplitude E-PNC in cesiu... more ABSTRACT We calculate the 6s-7s parity nonconserving (PNC) E1 transition amplitude E-PNC in cesium. We use an improved all-order technique in the calculation of the correlations and include all significant contributions to E-PNC. Our final value E-PNC = 0.904(1+/-0.5%) x 10(-11)iea(B)(-Q(W)/N) has half the uncertainty claimed in old calculations used for the interpretation of Cs PNC experiments. The resulting nuclear weak charge Q(W) for Cs deviates by about 2sigma from the value predicted by the standard model.
We follow our previous paper on possible cosmological variation of weak scale (quark masses) and ... more We follow our previous paper on possible cosmological variation of weak scale (quark masses) and strong scale, inspired by data on cosmological variation of the electromagnetic fine structure constant from distant quasar (QSO) absorption spectra. In this work we identify the strange quark mass ms as the most important quantity, and the sigma meson mass as the ingredient of the nuclear forces most sensitive to it. As a result, we claim significantly stronger limits on ratio of weak/strong scale (W = ms/ΛQCD) variation following from our previous discussion of primordial Big-Bang Nucleosynthesis (|δW/W | < 0.006) and Oklo natural nuclear reactor (|δW/W | < 1.2 • 10 −10 ; there is also a non-zero solution δW/W = (−0.56 ± 0.05) • 10 −9) .
We discuss limits on variation of (mq/ΛQCD). The results are obtained by studying n − αinteractio... more We discuss limits on variation of (mq/ΛQCD). The results are obtained by studying n − αinteraction during Big Bang, Oklo natural nuclear reactor data and limits on varition of the proton g-factor from quasar absorpion spectra.
The electromagnetic transition between the almost degenerate 5/2 + and 3/2 + states in 229 Th is ... more The electromagnetic transition between the almost degenerate 5/2 + and 3/2 + states in 229 Th is deemed to be very sensitive to potential changes in the fine structure constant α. State of the art Hartree-Fock and Hartree-Fock-Bogoliubov calculations are performed to compute the difference in Coulomb energies of the two states which determines the amplification of variations in α into variations of the transition frequency. The kinetic energies are also calculated which reflect a possible variation in the nucleon or quark masses. A generalized Hellmann-Feynman theorem is proved including the use of density-matrix functionals. As the two states differ mainly in the orbit occupied by the last unpaired neutron the Coulomb energy difference results from a change in the nuclear polarization of the proton distribution. This effect turns out to be rather small and to depend on the nuclear model, the amplification varies between about −4 × 10 4 and +4 × 10 4. Therefore much more effort must be put into the improvement of the nuclear models before one can draw conclusions from a measured drift in the transition frequency on a temporal drift of fundamental constants. All calculations published so far do not reach the necessary fidelity.
The effects of the variation of the dimensionless strong interaction parameter Xq = mq/ΛQCD (mq i... more The effects of the variation of the dimensionless strong interaction parameter Xq = mq/ΛQCD (mq is the quark mass, ΛQCD is the QCD scale) are enhanced about 1.5 • 10 5 times in the 7.6 eV "nuclear clock" transition between the ground and first excited states in the 229 Th nucleus and about 1 • 10 8 times in the relative shift of the 0.1 eV compound resonance in 150 Sm. The best terrestrial limit on the temporal variation of the fundamental constants, |δXq/Xq| < 4 • 10 −9 at 1.8 billion years ago (|Ẋq/Xq| < 2.2 • 10 −18 y −1) , is obtained from the shift of this Sm resonance derived from the Oklo natural nuclear reactor data. The results for 229 Th and 150 Sm are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the "direct" estimates obtained using the Walecka model. A number of numerical relations needed for the calculations of the variation effects in nuclear physics and atomic spectroscopy have been obtained: for the nuclear binding energy δE/E ≈ −1.45 δmq/mq, for the spin-orbit intervals δEso/Eso ≈ −0.22 δmq/mq, for the nuclear radius δr/r ≈ 0.3 δmq/mq (in units of ΛQCD); for the shifts of nuclear resonances and weakly bound energy levels δEr ≈ 10 δXq/Xq MeV.
Parity and time invariance violating forces produce collective P-and T-odd moments in nuclei with... more Parity and time invariance violating forces produce collective P-and T-odd moments in nuclei with static octupole deformation. Collective Schiff moment, electric octupole and dipole and also magnetic quadrupole appear due to the mixing of rotational levels of opposite parity and can exceed singleparticle moments by more than a factor of 100. This enhancement is due to two factors, the collective nature of the intrinsic moments and the small energy separation between members of parity doublets. The above moments induce T-and P-odd effects in atoms and molecules. Experiments with such systems may improve substantially the limits on time reversal violation.
The charge density of vector particles, for example W ± , may change sign. The effect manifests i... more The charge density of vector particles, for example W ± , may change sign. The effect manifests itself even for a free propagation; when the energy of the W-boson satisfies ε > √ 2m and the standing-wave is considered the charge density oscillates in space. The charge density of W also changes sign in a close vicinity of a Coulomb center. The dependence of this effect on the g-factor for an arbitrary vector boson, for example ρ-meson , is discussed. An origin of this surprising effect is traced to the electric quadrupole moment and spin-orbit interaction of vector particles. Their contributions to the current have a polarization nature. The charge density of this current, ρ Pol = −∇ • P, where P is an effective polarization vector that depends on the quadrupole moment and spin-orbit interaction, oscillates in space, producing zero contribution to the total charge.
A method to calculate the mean squared matrix element of weak interaction between compound states... more A method to calculate the mean squared matrix element of weak interaction between compound states is developed. The result is expressed in terms of matrix elements of the nucleon-nucleon strong and weak interactions times the Fermi distribution functions at finite temperature. Numerical calculations for 233 Th are in excellent agreement with recent measurements of parity nonconservation effects in neutron capture. In fact, our calculations prove that the factor of dynamical enhancement (ratio of compound-nucleus effect to single-particle one) really exceeds 100, thus making it unnesessary to assume a value of the weak constant bigger than standard one (g 10 8 ∼ 1 ÷ 4).
Scattering length, which can be measured in Bose-Einstein condensate and Feshbach molecule experi... more Scattering length, which can be measured in Bose-Einstein condensate and Feshbach molecule experiments, is extremely sensitive to the variation of fundamental constants, in particular, the electron-to-proton mass ratio (me/mp or me/ΛQCD, where ΛQCD is the QCD scale). Based on single-and two-channel scattering model, we show how the variation of the mass ratio propagates to the scattering length. Our results suggest that variation of me/mp on the level of 10 −11 ∼ 10 −14 can be detected near a narrow magnetic or an optical Feshbach resonance by monitoring the scattering length on the 1% level. Derived formulae may also be used to estimate the isotopic shift of the scattering length.
We describe the results of a search for time variability of the fine structure constant α using a... more We describe the results of a search for time variability of the fine structure constant α using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four independent samples, spanning ∼ 23% to 87% of the age of the universe. Each sample yields a smaller α in the past and the optical sample shows a 4σ deviation: ∆α/α = −0.72 ± 0.18 × 10 −5 over the redshift range 0.5 < z < 3.5. We find no systematic effects which can explain our results. The only potentially significant systematic effects push ∆α/α towards positive values, i.e. our results would become more significant were we to correct for them.
We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain ... more We perform calculations of the dependence of nuclear magnetic moments on quark masses and obtain limits on the variation of the fine structure constant ␣ and (m q /⌳ QCD) from recent measurements of hydrogen hyperfine ͑21 cm͒ and molecular rotational transitions in quasar absorption systems, atomic clock experiments with hyperfine transitions in H, Rb, Cs, Yb ϩ , Hg ϩ , and optical transition in Hg ϩ. Experiments with Cd ϩ , deuterium/hydrogen, molecular SF 6 , and Zeeman transitions in 3 He/Xe are also discussed.
We consider the scalar-tensor theories of gravity extended by the pseudoscalar couplings to matte... more We consider the scalar-tensor theories of gravity extended by the pseudoscalar couplings to matter and gauge fields and derive constraints on the CP-odd combinations of scalar and pseudoscalar couplings from laboratory spin precession experiments and from the evolution of photon polarization over cosmological distances. We show the complimentary character of local and cosmological constraints, and derive novel bounds on the pseudoscalar couplings to photons from the laboratory experiments. It is also shown that the more accurate treatment of the spin content of nuclei used in the spin precession experiments allows to tighten bounds on Lorentz-violating backgrounds coupled to the proton spin.
Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis J. C. Bere... more Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis J. C. Berengut (a) , E. Epelbaum (b) , V. V. Flambaum (a) , C. Hanhart (c),(d),(e) , U.-G. Meißner (c),(d),(e),(f),(g),(h) , J. Nebreda (i) , and J. R. Peláez (j)
It is believed that there may have been a large number of black holes formed in the very early un... more It is believed that there may have been a large number of black holes formed in the very early universe. These would have quantised masses. A charged "elementary black hole" (with the minimum possible mass) can capture electrons, protons and other charged particles to form a "black hole atom". We find the spectrum of such an object with a view to laboratory and astronomical observation of them, and estimate the lifetime of the bound states. There is no limit to the charge of the black hole, which gives us the possibility of observing Z > 137 bound states and transitions at the lower continuum. Negatively charged black holes can capture protons. For Z > 1, the orbiting protons will coalesce to form a nucleus (after β-decay of some protons to neutrons), with a stability curve different to that of free nuclei. In this system there is also the distinct possibility of single quark capture. This leads to the formation of a coloured black hole that plays the role of an extremely heavy quark interacting strongly with the other two quarks. Finally we consider atoms formed with much larger black holes.
ABSTRACT We calculate the 6s-7s parity nonconserving (PNC) E1 transition amplitude E-PNC in cesiu... more ABSTRACT We calculate the 6s-7s parity nonconserving (PNC) E1 transition amplitude E-PNC in cesium. We use an improved all-order technique in the calculation of the correlations and include all significant contributions to E-PNC. Our final value E-PNC = 0.904(1+/-0.5%) x 10(-11)iea(B)(-Q(W)/N) has half the uncertainty claimed in old calculations used for the interpretation of Cs PNC experiments. The resulting nuclear weak charge Q(W) for Cs deviates by about 2sigma from the value predicted by the standard model.
We follow our previous paper on possible cosmological variation of weak scale (quark masses) and ... more We follow our previous paper on possible cosmological variation of weak scale (quark masses) and strong scale, inspired by data on cosmological variation of the electromagnetic fine structure constant from distant quasar (QSO) absorption spectra. In this work we identify the strange quark mass ms as the most important quantity, and the sigma meson mass as the ingredient of the nuclear forces most sensitive to it. As a result, we claim significantly stronger limits on ratio of weak/strong scale (W = ms/ΛQCD) variation following from our previous discussion of primordial Big-Bang Nucleosynthesis (|δW/W | < 0.006) and Oklo natural nuclear reactor (|δW/W | < 1.2 • 10 −10 ; there is also a non-zero solution δW/W = (−0.56 ± 0.05) • 10 −9) .
We discuss limits on variation of (mq/ΛQCD). The results are obtained by studying n − αinteractio... more We discuss limits on variation of (mq/ΛQCD). The results are obtained by studying n − αinteraction during Big Bang, Oklo natural nuclear reactor data and limits on varition of the proton g-factor from quasar absorpion spectra.
The electromagnetic transition between the almost degenerate 5/2 + and 3/2 + states in 229 Th is ... more The electromagnetic transition between the almost degenerate 5/2 + and 3/2 + states in 229 Th is deemed to be very sensitive to potential changes in the fine structure constant α. State of the art Hartree-Fock and Hartree-Fock-Bogoliubov calculations are performed to compute the difference in Coulomb energies of the two states which determines the amplification of variations in α into variations of the transition frequency. The kinetic energies are also calculated which reflect a possible variation in the nucleon or quark masses. A generalized Hellmann-Feynman theorem is proved including the use of density-matrix functionals. As the two states differ mainly in the orbit occupied by the last unpaired neutron the Coulomb energy difference results from a change in the nuclear polarization of the proton distribution. This effect turns out to be rather small and to depend on the nuclear model, the amplification varies between about −4 × 10 4 and +4 × 10 4. Therefore much more effort must be put into the improvement of the nuclear models before one can draw conclusions from a measured drift in the transition frequency on a temporal drift of fundamental constants. All calculations published so far do not reach the necessary fidelity.
The effects of the variation of the dimensionless strong interaction parameter Xq = mq/ΛQCD (mq i... more The effects of the variation of the dimensionless strong interaction parameter Xq = mq/ΛQCD (mq is the quark mass, ΛQCD is the QCD scale) are enhanced about 1.5 • 10 5 times in the 7.6 eV "nuclear clock" transition between the ground and first excited states in the 229 Th nucleus and about 1 • 10 8 times in the relative shift of the 0.1 eV compound resonance in 150 Sm. The best terrestrial limit on the temporal variation of the fundamental constants, |δXq/Xq| < 4 • 10 −9 at 1.8 billion years ago (|Ẋq/Xq| < 2.2 • 10 −18 y −1) , is obtained from the shift of this Sm resonance derived from the Oklo natural nuclear reactor data. The results for 229 Th and 150 Sm are obtained by extrapolation from light nuclei where the many-body calculations can be performed more accurately. The errors produced by such extrapolation may be smaller than the errors of direct calculations in heavy nuclei. The extrapolation results are compared with the "direct" estimates obtained using the Walecka model. A number of numerical relations needed for the calculations of the variation effects in nuclear physics and atomic spectroscopy have been obtained: for the nuclear binding energy δE/E ≈ −1.45 δmq/mq, for the spin-orbit intervals δEso/Eso ≈ −0.22 δmq/mq, for the nuclear radius δr/r ≈ 0.3 δmq/mq (in units of ΛQCD); for the shifts of nuclear resonances and weakly bound energy levels δEr ≈ 10 δXq/Xq MeV.
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Papers by V. Flambaum