Download or read book Measurement of the Decay Parameter rho and a Search for Non Standard Model Decays in the Muon Decay Spectrum written by Ryan David Bayes and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the muon decay process?+? e+?e??? is a powerful constraint on the behaviour of the weak interaction, without contamination of the other, stronger, fundamental interactions. The spectrum measured from the momentum and angles of the decay positrons is parametrized using a set of four decay parameters. The purpose of the TWIST experiment is to measure these decay parameters to an unprecedented precision; an order of magnitude improvement in the uncertainties over measurements completed before the TWIST experiment. Measurements of the muon decay parameters constrain the values of a series of 19 weak coupling constants. In the standard model, V-A weak interaction, 18 of these constants are 0, while the remaining constant describes interactions between left handed particles, gV_LL= 1. The decay parameter? quantifies the behaviour of the spectrum with respect to momentum. According to the standard model the value of this parameter is 3/4. TWIST measured a value of? = 0.74991?0.00009(stat)?0.00028(sys). The measurement is limited by its systematic uncertainty, so a large focus of the experiment was on the determination and control of these uncertainties. The systematic uncertainties are derived from uncertainties in the detector construction and uncertainties in the biases generated by differences between the data and a matching Monte Carlo. Muon decay also limits the possibility of family symmetry breaking interactions. TWIST can be used to search for the possibility of muons decaying into a positron and a single unidentified neutral particle?+? e+X0 that does not otherwise interact with normal matter. The large momentum and angle acceptance of the TWIST spectrometer allows for searches of two body decays for masses of the X0 boson mX0? [0,80] MeV/c, with a variety of behaviours with respect to the angle of the positron track. Upper limits on massive and mass-less X0 decays are set with a 90% confidence level separately at parts per million for massive decays and parts in 10000 for mass-less decays.

Download or read book Measurement of the Decay Parameter Rho and a Search for Non Standard Model Decays in the Muon Decay Spectrum written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the muon decay process + e+e is a powerful constraint on the behaviour of the weak interaction, without contamination of the other, stronger, fundamental interactions. The spectrum measured from the momentum and angles of the decay positrons is parametrized using a set of four decay parameters. The purpose of the TWIST experiment is to measure these decay parameters to an unprecedented precision; an order of magnitude improvement in the uncertainties over measurements completed before the TWIST experiment. Measurements of the muon decay parameters constrain the values of a series of 19 weak coupling constants. In the standard model, V-A weak interaction, 18 of these constants are 0, while the remaining constant describes interactions between left handed particles, gV_LL= 1. The decay parameter quantifies the behaviour of the spectrum with respect to momentum. According to the standard model the value of this parameter is 3/4. TWIST measured a value of = 0.749910.00009(stat)0.00028(sys). The measurement is limited by its systematic uncertainty, so a large focus of the experiment was on the determination and control of these uncertainties. The systematic uncertainties are derived from uncertainties in the detector construction and uncertainties in the biases generated by differences between the data and a matching Monte Carlo. Muon decay also limits the possibility of family symmetry breaking interactions. TWIST can be used to search for the possibility of muons decaying into a positron and a single unidentified neutral particle + e+X0 that does not otherwise interact with normal matter. The large momentum and angle acceptance of the TWIST spectrometer allows for searches of two body decays for masses of the X0 boson mX0 [0,80] MeV/c, with a variety of behaviours with respect to the angle of the positron track. Upper limits on massive and mass-less X0 decays are set with a 90% confidence level separately at parts per million for massive decays and parts in.

Download or read book Measurement of the Decay Parameter Rho and a Search for Non Standard Model Decays in the Muon Decay Spectrum written by Ryan David Bayes and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of the Michel Parameter rho in Muon Decay written by James Raymond Musser and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The TWIST Collaboration has measured the Michel parameter [rho] in normal muon decay, [mu] --> [epsilon]v[subscript epsilon]v̄[subscript mu]. In the standard model of particle physics, [rho] = 3/4. Deviations from this value require mixing of left- and right-handed muon and electron couplings in the muon-decay Lagrangian. We find [rho] = 0.75080 "0.00032(stat.)"0.00097(syst.) "0.00023, where the last uncertainty represents the dependence of [rho] on the Michel parameter [eta]. This result sets new limits on the W[subscript]L - W[subscript]R mixing angle in left-right symmetric models.

Download or read book A Measurement of the Michel Parameter rho in Muon Decay written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An improved measurement of the Michel parameter [rho] in normal muon decay has been made using the MEGA positron spectrometer. Muons were stopped in the center of a large solenoid (1.5 T nominal field) and the momenta of positrons with energies over about 35 MeV were measured with a precision of about 0.6 MeV/c FWHM. There over 15 million events in each spectrum taken for three operating configurations. The previous result has a precision of [delta][rho]/[rho] = 0.003 based on a sample of about 1 million events in the positron energy spectrum. The present experiment expects to improve the precision by a factor of three to six, depending on the level of systematic uncertainties. The improved result is a precise test of the standard model of electroweak interactions for a purely leptonic process. It also provides a better constraint on the mixing angle in a left-right symmetric extension to the standard model.

Download or read book Measurement of the delta and eta Muon Decay Parameters written by Anthony Hillairet and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Muon decay is a unique process involving only the four leptons of the first two generations. This makes it an ideal framework to study the weak interaction. The momentum-angle spectrum of the decay positron can be studied using a general 4-fermion interaction model. Only four parameters are needed in this model to entirely describe the spectrum. The measurement of these four muon decay parameters, rho, eta, delta and Pmu xi, provide a direct test of the Standard Model and its extensions. This thesis presents the final results from the blind analysis of the decay parameter delta using the TWIST (TRIUMF Weak Interaction Symmetry Test) spectrometer. The new precision on the parameter delta is a factor of 11.5 better than the last experimental result prior to TWIST achieving the goal of the TWIST collaboration of an order of magnitude improvement. The challenging parameter eta is also measured from the momentum-angle spectrum for the first time since 1969 with a precision improved by a factor of 7.4. The results are included in a global analysis to obtain stringent limits on some of the coupling constants of the 4-fermion interaction. The result of the measurement of delta are used to evaluate the possibility for a non-local tensor interaction.

Download or read book Measurement of the Delta and Eta Muon Decay Parameters written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Muon decay is a unique process involving only the four leptons of the first two generations. This makes it an ideal framework to study the weak interaction. The momentum-angle spectrum of the decay positron can be studied using a general 4-fermion interaction model. Only four parameters are needed in this model to entirely describe the spectrum. The measurement of these four muon decay parameters, rho, eta, delta and Pmu xi, provide a direct test of the Standard Model and its extensions. This thesis presents the final results from the blind analysis of the decay parameter delta using the TWIST (TRIUMF Weak Interaction Symmetry Test) spectrometer. The new precision on the parameter delta is a factor of 11.5 better than the last experimental result prior to TWIST achieving the goal of the TWIST collaboration of an order of magnitude improvement. The challenging parameter eta is also measured from the momentum-angle spectrum for the first time since 1969 with a precision improved by a factor of 7.4. The results are included in a global analysis to obtain stringent limits on some of the coupling constants of the 4-fermion interaction. The result of the measurement of delta are used to evaluate the possibility for a non-local tensor interaction.

Download or read book Measurement of the Delta and Eta Muon Decay Parameters written by Anthony Hillairet and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Exotic Muon Decays in the TWIST Muon Decay Spectrum written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The search for lepton flavour violation is significant to our understanding of the standard model of particle physics. This measurement uses the muon decay data collected by the TWIST experiment at TRIUMF to search for lepton flavour violation between charged lepton species. Specifically, I searched for the decay æ+2!+X0, where X° is an unknown, undetected, neutral boson, against a background of stanƠdard muon decays, æ+2!+vevæ I set branching ratios for these decays such that B(æ+2!+X0)

Download or read book Energy Research Abstracts written by and published by . This book was released on 1989 with total page 1398 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Precision Measurement of the Muon Decay Parameters Rho and Delta written by Robert Paul MacDonald and published by . This book was released on 2008 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Physics Briefs written by and published by . This book was released on 1991 with total page 1454 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of The Parameter In Decay written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper discusses the following topics on the muon plus decay; muon decay spectrum; previous determinations of?; experimental apparatus; distortions of the spectrum; and data analysis and results. 31 figs. (LSP).

Download or read book High Energy Physics Index written by and published by . This book was released on 1993 with total page 640 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book MUON DECAY ASYMMETRIES FROM KOL YIELDS POM M DECAYS written by and published by . This book was released on 2001 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have examined the decay K{sub L}° →?°??− in which the branching ratio, the muon energy asymmetry and the muon decay asymmetry could be measured. In particular, we find that within the Standard Model the longitudinal polarization (PL) of the muon is proportional to the direct CP violating amplitude. On the other hand the energy asymmetry and the out-of-plane polarization (P{sub N}) depend on both indirect and direct CP violating amplitudes. Although the branching ratio is small and difficult to measure because of background, the asymmetries could be large?(1) in the Standard Model. A combined analysis of the energy asymmetry, P{sub L} and P{sub N} could be used to separate indirect, CPV, direct CPV, and CP conserving contributions to the decay.

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975-12 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt: