A search for μ-e conversion in muonic gold Bertl, W.; Engfer, R.; Hermes, E.A. ...
The European physical journal. C, Particles and fields,
8/2006, Letnik:
47, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We report on a search for μ-e conversion in muonic gold performed with the SINDRUM II spectrometer at PSI. The measurement resulted in Γ(μ-Au→e-Aug.s.)/Γcapture(μ-Au)<7×10-13 (90% C.L.).
The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 ppm (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in ...2001, and is over an order of magnitude more precise than the previous measurement for the negative muon. The result a(mu(-))=11 659 214(8)(3) x 10(-10) (0.7 ppm), where the first uncertainty is statistical and the second is systematic, is consistent with previous measurements of the anomaly for the positive and the negative muon. The average of the measurements of the muon anomaly is a(mu)(exp)=11 659 208(6) x 10(-10) (0.5 ppm).
A higher precision measurement of the anomalous g value, a(mu)=(g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron, based on data collected in the year ...2000. The result a(mu(+))=11 659 204(7)(5)x10(-10) (0.7 ppm) is in good agreement with previous measurements and has an error about one-half that of the combined previous data. The present world average experimental value is a(mu)(expt)=11 659 203(8)x10(-10) (0.7 ppm).
A precise measurement of the anomalous g value, a(mu) = (g-2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a(mu+) = 11 659 202(14) (6) x ...10(-10) (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is a(mu)(SM) = 11 659 159.6(6.7) x 10(-10) (0.57 ppm) and a(mu)(exp) - a(mu)(SM) = 43(16) x 10(-10) in which a(mu)(exp) is the world average experimental value.
A recent result of the cross section measurement of the process e + e − → K S K π at e + e − collider VEPP-2000 is presented using a data sample of the ∼150 pb−1 integrated luminosity collected with ...the CMD-3 detector. The processes with charged kaons in multi hadron events attract special interest, because they impact strongly on studies of light quark hadronization, isospin symmetry, and strange meson spectroscopy. Experimental results of e + e − → K S K π cross section are presented in a broad energy range covered by the VEPP-2000 and compared to earlier measurements. A study of the production dynamics confirms the dominance of neutral KK * ( 892 ) intermediate state.
The time-of-flight (TOF) system now is installed at the CMD-3 detector of the VEPP-2000 electron-positron collider at the Budker Institute of Nuclear Physics. It is based on the strips of organic ...scintillator with shifter fibers readout and silicon photomultiplier (SiPM) photodetectors. The new electronics for TOF system is designed at the Budker Institute of Nuclear Physics. The main feature of the new electronics is usage a ripple-free technology for providing a bias voltage for SiPM photodetectors. Also this design has very low power consumption. It allows the individual controlled bias voltage generator to be integrated to front-end electronics, near the photodetectors. In this paper the structure of the TOF electronic hardware is described.
The spin precession frequency of muons stored in the (g-2) storage ring has been analyzed for evidence of Lorentz and CPT violation. Two Lorentz and CPT violation signatures were searched for a ...nonzero delta omega a(=omega a mu+ - omega a mu-) and a sidereal variation of omega a mu+/-). No significant effect is found, and the following limits on the standard-model extension parameters are obtained: bZ = -(1.0+/-1.1) x 10(-23) GeV; (m mu dZ0 + HXY)=(1.8+/-6.0) x 10(-23) GeV; and the 95% confidence level limits b perpendicular mu+ <1.4 x 10(-24) GeV and b perpendicular mu- <2.6 x 10(-24) GeV.
The results of the experiment on the measurement of the e+e− → π+π− cross section in a cm energy range of 370–520 MeV are presented. The systematic measurement error is equal to 0.7%. In the vector ...dominance model, the pion electromagnetic radius is calculated using all the CMD-2 data on the pion form factor. The cross section for the production of a muon pair is measured in the energy range of the experiment.
Upgrade of the CMD-3 TOF system Fedotovich, G V; Kozyrev, A N; Kulidzhoglyan, V A ...
Journal of instrumentation,
09/2014, Letnik:
9, Številka:
9
Journal Article
Recenzirano
The upgrade of the CMD-3 Time of Flight system (TOF) based on strip scintillation counters is described. The TOF is located inside 7 mm gap between LXe and CsI barrel calorimeters. The principal ...objective of this system is to identify slow antineutrons produced in the reaction e super(+)e sub(-) arrow right nn. Due to low velocities these antineutrons annihilate in calorimeters and have a typical delay time about 4-10 ns with respect to the beam crossing in VEPP-2000 e super(+)e super(-) collider. The signals coming from strip scintillation counters are readout by two SiPM on both sides of the strip. Time resolution is measured with cosmic rays and is ~1 ns.
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