A Further Study of the Inertia of the Electric Carrier in Copper

Nature of the experiments.—An apparatus similar to that of Tolman, Karrer and Guernsey, in which a copper cylinder is oscillated around its axis and the current due to the lag of the electrons in the cylinder detected by means of a secondary of many turns of fine wire connected through an amplifier with a tuned vibration galvanometer, has been used for a further study of the inertia of the electric carrier in metals. The method has been improved, among other ways by arranging to measure the direction, phase, and magnitude of the alternating current produced by the acceleration instead of merely determining the amplitude of the effect, as was done in the earlier experiments. The null method of balancing out the electromotive force of interest, introduced for this purpose, also had the advantage of eliminating the previous uncertain correction for the "zero effect." A thorough study of the effect of the earth's field on the moving cylinder was also made, which has not been previously done. Results.—The effect of the earth's field in inducing currents in the moving apparatus was found to be in accord with that theoretically predicted, and it was satisfactorily demonstrated that this effect is eliminated when the cylinder is set parallel to the field and the coil set parallel to the cylinder. The final best value for the electromotive force produced by the acceleration was found to have an amplitude 19% less and a phase lagging 10° behind that predicted on the basis of an elementary theory which assumes a perfectly rigid conductor with "free" conducting electrons having the same mass as electrons in free space. It is not certain whether this discrepancy is due to errors still present in the experimental work, or due to the over simplification introduced in the deduction of the elementary theory. The results are presumably more reliable than those of Tolman, Karrer and Guernsey which gave an amplitude 8% lower than the predicted, using the same apparatus in a less satisfactory form. The results should also be compared with those of Tolman and Stewart who measured the pulse of current produced by suddenly stopping a coil of wire rotating around its axis, and found values about 15% greater than the predicted. A possible source of error in their experiments, due to interaction between metal and insulation, was discovered in the present work, but it may be that there is a real difference in the effective mass of the carrier in the two kinds of experiment. It is believed that the present work demonstrates more satisfactorily than ever before the actual existence of an electromotive force due to the inertia of the electrons in an accelerated metallic conductor

The lack of effect of a magnetic field on the dielectric constant of HCl and NO

Using an electron tube method, experiments have been performed to test whether the dielectric constant of HCl and NO gases changes when a strong magnetic field is applied. The magnetic field strength was 4800 gauss and the apparatus was capable of definitely detecting a change in dielectric constant of one part in 100,000. The gases were tested at pressures of from about 2 to 40 cm of mercury, at room temperature, and with the magnetic field both parallel and perpendicular to the electric field. No change was detected under any conditions

Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay

We reconstruct the rare decays $B^+ \to K^+\mu^+\mu^-$, $B^0 \to K^{*}(892)^0\mu^+\mu^-$, and $B^0_s \to \phi(1020)\mu^+\mu^-$ in a data sample corresponding to $4.4 {\rm fb^{-1}}$ collected in $p\bar{p}$ collisions at $\sqrt{s}=1.96 {\rm TeV}$ by the CDF II detector at the Fermilab Tevatron Collider. Using $121 \pm 16$ $B^+ \to K^+\mu^+\mu^-$ and $101 \pm 12$ $B^0 \to K^{*0}\mu^+\mu^-$ decays we report the branching ratios. In addition, we report the measurement of the differential branching ratio and the muon forward-backward asymmetry in the $B^+$ and $B^0$ decay modes, and the $K^{*0}$ longitudinal polarization in the $B^0$ decay mode with respect to the squared dimuon mass. These are consistent with the theoretical prediction from the standard model, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the $B^0_s \to \phi\mu^+\mu^- decay and measure its branching ratio${\mathcal{B}}(B^0_s \to \phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}$using$27 \pm 6$signal events. This is currently the most rare$B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let

Measurements of the properties of Lambda_c(2595), Lambda_c(2625), Sigma_c(2455), and Sigma_c(2520) baryons

We report measurements of the resonance properties of Lambda_c(2595)+ and Lambda_c(2625)+ baryons in their decays to Lambda_c+ pi+ pi- as well as Sigma_c(2455)++,0 and Sigma_c(2520)++,0 baryons in their decays to Lambda_c+ pi+/- final states. These measurements are performed using data corresponding to 5.2/fb of integrated luminosity from ppbar collisions at sqrt(s) = 1.96 TeV, collected with the CDF II detector at the Fermilab Tevatron. Exploiting the largest available charmed baryon sample, we measure masses and decay widths with uncertainties comparable to the world averages for Sigma_c states, and significantly smaller uncertainties than the world averages for excited Lambda_c+ states.Comment: added one reference and one table, changed order of figures, 17 pages, 15 figure

Search for a New Heavy Gauge Boson Wprime with Electron + missing ET Event Signature in ppbar collisions at sqrt(s)=1.96 TeV

We present a search for a new heavy charged vector boson $W^\prime$ decaying to an electron-neutrino pair in $p\bar{p}$ collisions at a center-of-mass energy of 1.96\unit{TeV}. The data were collected with the CDF II detector and correspond to an integrated luminosity of 5.3\unit{fb}^{-1}. No significant excess above the standard model expectation is observed and we set upper limits on $\sigma\cdot{\cal B}(W^\prime\to e\nu)$. Assuming standard model couplings to fermions and the neutrino from the $W^\prime$ boson decay to be light, we exclude a $W^\prime$ boson with mass less than 1.12\unit{TeV/}c^2 at the 95\unit{%} confidence level.Comment: 7 pages, 2 figures Submitted to PR

Multiplicity and rapidity dependence of strange hadron production in pp, pPb, and PbPb collisions at the LHC

Peer reviewe

Measurement of inclusive jet production and nuclear modifications in pPb collisions at root s(NN)=5.02 TeV

Peer reviewe

Searches for R-parity-violating supersymmetry in pp collisions at √s=8 TeV in final states with 0–4 leptons

Peer reviewe

Search for dark matter particles in proton-proton collisions at √s=8 TeV using the razor variables

A search for dark matter particles directly produced in proton-proton collisions recorded by the CMS experiment at the LHC is presented. The data correspond to an integrated luminosity of 18.8 fb−1, at a center-of-mass energy of 8 TeV. The event selection requires at least two jets and no isolated leptons. The razor variables are used to quantify the transverse momentum balance in the jet momenta. The study is performed separately for events with and without jets originating from b quarks. The observed yields are consistent with the expected backgrounds and, depending on the nature of the production mechanism, dark matter production at the LHC is excluded at 90% confidence level for a mediator mass scale Λ below 1 TeV. The use of razor variables yields results that complement those previously published