Search results for "DIPOLE"
showing 10 items of 982 documents
Resonance interaction energy between two entangled atoms in a photonic bandgap environment
2018
We consider the resonance interaction energy between two identical entangled atoms, where one is in the excited state and the other in the ground state. They interact with the quantum electromagnetic field in the vacuum state and are placed in a photonic-bandgap environment with a dispersion relation quadratic near the gap edge and linear for low frequencies, while the atomic transition frequency is assumed to be inside the photonic gap and near its lower edge. This problem is strictly related to the coherent resonant energy transfer between atoms in external environments. The analysis involves both an isotropic three-dimensional model and the one-dimensional case. The resonance interaction…
Line shifts and broadenings in polarizable liquids
1989
We present a new dynamical derivation of the approximation used by Thompson, Schweizer, and Chandler and by Ho/ye and Stell for the frequency dependent polarizability of a quantum fluid with harmonically bound dipole moments; the Drude model. The derivation is the same for classical and quantum liquids—as is of course the result which agrees with that of these authors. We then refine the theory by taking account of the limited number of energy levels available, i.e., we replace the harmonic approximation by a two level approximation, for the target atom. This leads to a prefactor ω0I/ω0 in the line shift of an impurity atom in a fluid computed by Chandler, Schweitzer, and Wolynes: ω0 and ω0…
The influence of quantum fluctuations on phase transition temperature in disordered ferroelectrics
2014
We consider the disordered ferroelectric, where the impurity dipoles interact via quantum optical phonons. We show that quantum fluctuations are amplified by the effects of disorder so that they can be important up to the ferroelectric phase transition temperature. In this paper, we calculate the ferroelectric phase transition temperature as a function of impurity dipole concentration. We show that quantum effects change the character of concentrational dependence of . Namely, they cause the discontinuity in so that the critical concentration is reached abruptly. We have shown that quantum effects inhibit the ferroelectricity so that larger (than that in purely classical disordered ferroele…
Search for CP-violating nuclear magnetic quadrupole moment using the LuOH+ cation
2020
The time-reversal and spatial parity violating interaction of the nuclear magnetic quadrupole moment (MQM) of the 175Lu and 176Lu nuclei with electrons in the molecular cation LuOH+ is studied. The resulting effect is expressed in terms of fundamental parameters, such as quantum chromodynamics angle θ⎯⎯, quark electric dipole moment (EDM), and chromo-EDM. For this, we have estimated the magnetic quadrupole moments of 175Lu and 176Lu nuclei and calculated the molecular constant that characterizes the interaction of the MQM with electrons in the considered molecules. Additionally, we predict the hyperfine structure constants for the ground electronic state of LuOH+. In the molecular calculati…
Exclusive heavy vector meson production at next-to-leading order in the dipole picture
2021
We calculate exclusive production of a longitudinally polarized heavy vector meson at next-to-leading order in the dipole picture. The large quark mass allows us to separately include both the first QCD correction proportional to the coupling constant $\alpha_s$, and the first relativistic correction suppressed by the quark velocity $v^2$. Both of these corrections are found to be numerically important in $\mathrm{J}/\psi$ production. The results obtained are directly suitable for phenomenological calculations. We also demonstrate how vector meson production provides complementary information to structure function analyses when one extracts the initial condition for the energy evolution of …
Measurement of trilinear gauge boson couplings WWV, (V Z,gamma) in e(+)e(-) collisions at 189 GeV
2001
Measurements of the trilinear gauge boson couplings WWgamma and WWZ are presented using the data taken by DELPHI in 1998 at a centre-of-mass energy of 189 GeV and combined with DELPHI data at 183 GeV. Values are determined for Delta(g_1^Z) and Delta(kappa_gamma), the differences of the WWZ charge coupling and of the WWgamma dipole coupling from their Standard Model values, and for lambda_gamma, the WWgamma quadrupole coupling. A measurement of the magnetic dipole and electric quadrupole moment of the W is extracted from the results for Delta(kappa_gamma) and lambda_gamma. The study uses data from the final states jjlv, jjjj, lX, jjX and gammaX, where j represents a quark jet, l an identifie…
Electromagnetic structure of few-nucleon ground states
2015
Experimental form factors of the hydrogen and helium isotopes, extracted from an up-to-date global analysis of cross sections and polarization observables measured in elastic electron scattering from these systems, are compared to predictions obtained in three different theoretical approaches: the first is based on realistic interactions and currents, including relativistic corrections (labeled as the conventional approach); the second relies on a chiral effective field theory description of the strong and electromagnetic interactions in nuclei (labeled $\chi$EFT); the third utilizes a fully relativistic treatment of nuclear dynamics as implemented in the covariant spectator theory (labeled…
Color glass condensate at next-to-leading order meets HERA data
2020
We perform the first dipole picture fit to HERA inclusive cross section data using the full next-to-leading order (NLO) impact factor combined with an improved Balitsky-Kovchegov evolution including the dominant effects beyond leading logarithmic accuracy at low $x$. We find that three different formulations of the evolution equation that have been proposed in the recent literature result in a very similar description of HERA data, and robust predictions for future deep inelastic scattering experiments. We find evidence pointing towards a significant nonperturbative contribution to the structure function for light quarks, which stresses the need to extend the NLO impact factor calculation t…
Time reversal invariance violation in neutron-nucleus scattering
2019
Planning and interpretation of the experiments searching for the time reversal (T) and parity (P) violation in neutron reactions require values of the matrix elements of the T,P-violating nuclear forces between nuclear compound states. We calculate the root mean square values and the ratio of the matrix elements of the T,P-violating and P-violating interactions using statistical theory based on the properties of chaotic compound states and present the results in terms of the fundamental parameters in four different forms: in terms of the constants of the contact nuclear interaction, meson exchange constants, QCD theta-term and quark chromo-EDMs. Using current limits on these parameters, we …
Massive quarks in NLO dipole factorization for DIS : Longitudinal photon
2021
In this work, we will present the first complete calculation of the one-loop longitudinal photon-to-quark-antiquark light cone wave function, with massive quarks. The quark masses are renormalized in the pole mass scheme. The result is used to calculate the next-to-leading order correction to the high energy Deep Inelastic Scattering longitudinal structure function on a dense target in the dipole factorization framework. For massless quarks the next-to-leading order correction was already known to be sizeable, and our result makes it possible to evaluate it also for massive quarks.