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We present a combined analysis of the available isotope-shift data from the optical spectra of Ra atoms and Ra${}^{+}$ ions. Atomic structure calculations of the field-shift and specific mass-shift constants of the low-lying levels in Ra${}^{+}$ are used. The nuclear radial differences $\ensuremath{\delta}\ensuremath{\langle}{r}^{2}\ensuremath{\rangle}$ for the radium isotopes are derived and compared to previous analyses and nuclear models. We discuss the relevance of our results to measurements of atomic parity violation in a chain of Ra${}^{+}$ isotopes.

Laser spectroscopy of short-lived radium isotopes in a linear Paul trap has been performed. The isotope shifts of the 6d(2)D(3/2)-7p(2)P(1/2) transition in Ra-209-214(+), which are sensitive to the short-range part of the atomic wave functions, were measured. The results are essential experimental input for improving the precision of atomic structure calculations. This is indispensable for parity violation in Ra+ aiming at the determination of the weak mixing angle.

Laser spectroscopy of short-lived radium isotopes in a linear Paul trap has been performed. The isotope shifts of the 6d(2)D(3/2)-7p(2)P(1/2) transition in Ra-209-214(+), which are sensitive to the short-range part of the atomic wave functions, were measured. The results are essential experimental input for improving the precision of atomic structure calculations. This is indispensable for parity violation in Ra+ aiming at the determination of the weak mixing angle.

Laser spectroscopy of short-lived radium isotopes in a linear Paul trap has been performed. The isotope shifts of the 6d(2)D(3/2)-7p(2)P(1/2) transition in Ra-209-214(+), which are sensitive to the short-range part of the atomic wave functions, were measured. The results are essential experimental input for improving the precision of atomic structure calculations. This is indispensable for parity violation in Ra+ aiming at the determination of the weak mixing angle.

Laser spectroscopy of short-lived radium isotopes in a linear Paul trap has been performed. The isotope shifts of the 6d(2)D(3/2)-7p(2)P(1/2) transition in Ra-209-214(+), which are sensitive to the short-range part of the atomic wave functions, were measured. The results are essential experimental input for improving the precision of atomic structure calculations. This is indispensable for parity violation in Ra+ aiming at the determination of the weak mixing angle.

Atomic parity violation (APV) can be measured in a single Ra(+) ion, enabling a precise measurement of the electroweak mixing angle in the Standard Model of particle physics at low momentum transfer. This provides sensitivity to new particles such as extra Z(0) bosons or leptoquarks. The Weinberg angle can be measured via a determination of the light shift in the forbidden 7(2)S(1/2)-6(2)D(3/2) transition in a single trapped Ra(+). Ultra-narrow transitions in such an ideal system can also be exploited to realize a high stability frequency standard. At the TRI mu P facility of KVI, we have succeeded in the production of a series of radioactive short-lived radium isotopes. The radium isotopes produced were stopped and thermalized to Ra(+) in a thermal ionizer, mass separated in a Wien filter, cooled in a gas filled radio frequency quadrupole and subsequently trapped as a cloud in a linear Paul trap. Laser spectroscopy in the trapped radium ions has been performed. The results of hyperfine structure, isotope shift, and lifetime measurements are important experimental inputs to test the accuracy of atomic theory, the precision of which is indispensable for extracting the Weinberg angle. These results are also of relevance for a possible atomic clock, based on trapped Ra(+).

Atomic parity violation (APV) can be measured in a single Ra(+) ion, enabling a precise measurement of the electroweak mixing angle in the Standard Model of particle physics at low momentum transfer. This provides sensitivity to new particles such as extra Z(0) bosons or leptoquarks. The Weinberg angle can be measured via a determination of the light shift in the forbidden 7(2)S(1/2)-6(2)D(3/2) transition in a single trapped Ra(+). Ultra-narrow transitions in such an ideal system can also be exploited to realize a high stability frequency standard. At the TRI mu P facility of KVI, we have succeeded in the production of a series of radioactive short-lived radium isotopes. The radium isotopes produced were stopped and thermalized to Ra(+) in a thermal ionizer, mass separated in a Wien filter, cooled in a gas filled radio frequency quadrupole and subsequently trapped as a cloud in a linear Paul trap. Laser spectroscopy in the trapped radium ions has been performed. The results of hyperfine structure, isotope shift, and lifetime measurements are important experimental inputs to test the accuracy of atomic theory, the precision of which is indispensable for extracting the Weinberg angle. These results are also of relevance for a possible atomic clock, based on trapped Ra(+).

Atomic parity violation (APV) can be measured in a single Ra(+) ion, enabling a precise measurement of the electroweak mixing angle in the Standard Model of particle physics at low momentum transfer. This provides sensitivity to new particles such as extra Z(0) bosons or leptoquarks. The Weinberg angle can be measured via a determination of the light shift in the forbidden 7(2)S(1/2)-6(2)D(3/2) transition in a single trapped Ra(+). Ultra-narrow transitions in such an ideal system can also be exploited to realize a high stability frequency standard. At the TRI mu P facility of KVI, we have succeeded in the production of a series of radioactive short-lived radium isotopes. The radium isotopes produced were stopped and thermalized to Ra(+) in a thermal ionizer, mass separated in a Wien filter, cooled in a gas filled radio frequency quadrupole and subsequently trapped as a cloud in a linear Paul trap. Laser spectroscopy in the trapped radium ions has been performed. The results of hyperfine structure, isotope shift, and lifetime measurements are important experimental inputs to test the accuracy of atomic theory, the precision of which is indispensable for extracting the Weinberg angle. These results are also of relevance for a possible atomic clock, based on trapped Ra(+).

This document reports on an effort in improving low energy tests of neutral current weak interactions. The goal is to realize a 1% precision measurement of a parity nonconserving transition dipole in cesium vapor using laser pump-probe polarimetry. This experiments differs from all other parity nonconservation measurements in the use of stimulated emission by a probe beam, a situation in which the left-right asymmetry is amplified when the probe gain increases. Many experimental techniques have been improved for this measurement: design and realization of the vapor cells, control of the surface effects, control and reduction of the effects associated with the cesium dimers, measurement, control and reduction of the stray fields. Beyond the implementation of dedicated techniques, i) this work has raised the parity violation measurement to a 2.6% achieved precision and to a signal/noise figure that allows to reach the 1% precision level, ii) original experiments have been done such as the near-IR laser dissociation of Cs dimers, observation without background of the zero-field 6S-7S transition, implementation of spectroscopic cells without reflection at the windows, the demonstration that laser diffraction can be used to monitor the monoatomic steps at a vicinal single-crystal surface, a method for homodyne detection of selective reflection, or absolute measurements of cross-sections, iii) a scheme has been proposed that would allow a 0.1% precision parity nonconservation measurement at the shot noise limit, and a study, of how the spectroscopy of forbidden transitions could benefit from laser cooling techniques, has been done, Le travail présenté ici a pour but l'amélioration des tests de basse énergie des interactions faibles à courant neutre. Il a porté sur la mise au point d'une expérience à même de réaliser une mesure d'un dipôle de transition violant la parité dans une vapeur de césium en cellule avec une précision de 1% sur un montage de polarimétrie laser pompe-sonde. Son caractère original tient à la détection d'une transition interdite dans une vapeur, non plus par fluorescence comme l'ont fait toutes les expériences antérieures, mais par l'émission stimulée par le faisceau sonde, ce qui amplifie l'asymétrie à mesurer lorsque l'amplification du faisceau sonde est importante. De nombreux aspects expérimentaux ont nécessité de repousser les limites de l'expérimentation: amélioration des techniques de polarimétrie avec des lasers en impulsions, conception et préparation des cellules, maîtrise des effets de surface, maîtrise et réduction des effets liés aux dimères de césium, étude des champs parasites, puis de leur contrôle/réduction. Mais par-delà le développement de savoir-faire spécifiques, ce travail i) a permis d'amener l'expérience VPA à un stade où la précision de la mesure déjà effectuée est de 2,6%, et où le rapport signal/bruit atteint permet de se lancer dans une mesure à 1%; ii) a donné lieu à des expériences originales comme la photo-destruction des dimères d'une vapeur de césium, l'observation en champ nul et sans background de la transition 6S-7S en champ nul, la réalisation de cellules spectroscopiques "sans pertes par réflexion", la mise en évidence, par diffraction laser, des marches monoatomiques d'une surface vicinale ou encore des méthodes originales de détection homodyne du signal de réflexion sélective ou de mesure absolue de sections efficaces; iii) propose une méthode susceptible de permettre une mesure VPA à 0,1%, ainsi qu'une exploration de ce que permettrait le refroidissement laser pour l'étude des transitions interdites.

A search for physics beyond the Standard Model has been performed with high-Q^2 neutral current deep inelastic scattering events recorded with the ZEUS detector at HERA. Two data sets, e^+ p \to e^+ X and e^- p \to e^- X, with respective integrated luminosities of 112 pb^-1 and 16 pb^-1, were analyzed. The data reach Q^2 values as high as 40000 GeV^2. No significant deviations from Standard Model predictions were observed. Limits were derived on the effective mass scale in eeqq contact interactions, the ratio of leptoquark mass to the Yukawa coupling for heavy leptoquark models and the mass scale parameter in models with large extra dimensions. The limit on the quark charge radius, in the classical form factor approximation, is 0.85 10^-16 cm., Comment: 28 pages, 4 figures, accepted for publication in Physics Letters B

The neutron distributions of Cs, Ba, Yb and Pb isotopes are described in the framework of relativistic mean-field theory. The self-consistent ground state proton and neutron density distributions are calculated with the relativistic Hartree-Bogoliubov model. The binding energies, the proton and neutron radii, and the quadrupole deformations are compared with available experimental data, as well as with recent theoretical studies of the nuclear structure corrections to the weak charge in atomic parity nonconservation experiments., 16 pages, RevTex, 11 eps figs, submitted to Phys. Rev. C

parity or space parity, in physics, quantity that refers to the relationship between an object or process and the image that it can produce in a mirror. For example, any […]