Although the scale of electroweak symmetry breaking is well established, the mechanism of that br... more Although the scale of electroweak symmetry breaking is well established, the mechanism of that breaking is still unknown. Data collected at the CERN ee collider LEP over the last twelve years, however, have provided many constraints on the properties of that mechanism. In this paper, we consider what the LEP data reveal about nonminimal technicolor models. In particular, we explore how the limits on rare processes constrain technicolor models with neutral pseudo–Nambu-Goldstone bosons PNGBs, Pa, which couple, through an ...
The new E969 muon g-2 experiment at BNL will need to run at significantly higher stored muon rate... more The new E969 muon g-2 experiment at BNL will need to run at significantly higher stored muon rate to collect the necessary statistics in a reasonable time. The higher instantaneous decay electron rate will require a new segmented calorimeter to keep the systematic error from pileup small. A fast, tungsten-scintillating fiber calorimeter with PMT readout has been designed for this purpose. The high density of tungsten results in compact showers, which are necessary both to distinguish multiple simultaneous showers and to satisfy strict space constraints. Beam tests and Monte Carlo simulations of a single calorimeter segment have been performed. Analysis of these studies indicates that the new design should satisfy the requirements of the g-2 experiment.
We propose to measure the rate \Rd\ for muon capture on the deuteron to better than 1.5% precisio... more We propose to measure the rate \Rd\ for muon capture on the deuteron to better than 1.5% precision. This process is the simplest weak interaction process on a nucleus that can both be calculated and measured to a high degree of precision. The measurement will provide a benchmark result, far more precise than any current experimental information on weak interaction processes in the two-nucleon system. Moreover, it can impact our understanding of fundamental reactions of astrophysical interest, like solar pp fusion and the $\nu+d$ reactions observed by the Sudbury Neutrino Observatory. Recent effective field theory calculations have demonstrated, that all these reactions are related by one axial two-body current term, parameterized by a single low-energy constant. Muon capture on the deuteron is a clean and accurate way to determine this constant. Once it is known, the above mentioned astrophysical, as well as other important two-nucleon reactions, will be determined in a model indepe...
WFD samples (2 ns each) 10 20 30 40 50 60 WFD ADC value 0 50 100 150 200 250 Waveform Digitizer t... more WFD samples (2 ns each) 10 20 30 40 50 60 WFD ADC value 0 50 100 150 200 250 Waveform Digitizer trace (a) Three pulses close together in one channel are easily distinguishable using waveform digitizers. (b) Online monitoring tools permit real time track-ing of observed muon decays as a function of time. Figure 1: The data sample of 8 × 10 10 muons collected in 2005 should yield a muon lifetime measurement with a statistical uncertainty of 4 ppm.
... (3) which is based on the 2008 summary of the standard model (SM) by de Rafael [3]. A ... one... more ... (3) which is based on the 2008 summary of the standard model (SM) by de Rafael [3]. A ... one can accept that QED is valid and use the electron anomaly to determine the most precise measurement of α, which de Rafael uses in his evaluation[3] of the QED contribution to aµ. 17 ...
The muLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muo... more The muLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muon with a precision of 1 ppm, giving a value for the Fermi coupling constant G_F at the level of 0.5 ppm. Meanwhile, by measuring the observed lifetime of the negative muon in pure hydrogen, the muCap experiment will determine the rate of muon capture, giving the proton's pseudoscalar coupling g_p to 7%. This coupling can be calculated precisely from heavy baryon chiral perturbation theory and therefore permits a test of QCD's chiral symmetry.
Although the scale of electroweak symmetry breaking is well established, the mechanism of that br... more Although the scale of electroweak symmetry breaking is well established, the mechanism of that breaking is still unknown. Data collected at the CERN ee collider LEP over the last twelve years, however, have provided many constraints on the properties of that mechanism. In this paper, we consider what the LEP data reveal about nonminimal technicolor models. In particular, we explore how the limits on rare processes constrain technicolor models with neutral pseudo–Nambu-Goldstone bosons PNGBs, Pa, which couple, through an ...
The new E969 muon g-2 experiment at BNL will need to run at significantly higher stored muon rate... more The new E969 muon g-2 experiment at BNL will need to run at significantly higher stored muon rate to collect the necessary statistics in a reasonable time. The higher instantaneous decay electron rate will require a new segmented calorimeter to keep the systematic error from pileup small. A fast, tungsten-scintillating fiber calorimeter with PMT readout has been designed for this purpose. The high density of tungsten results in compact showers, which are necessary both to distinguish multiple simultaneous showers and to satisfy strict space constraints. Beam tests and Monte Carlo simulations of a single calorimeter segment have been performed. Analysis of these studies indicates that the new design should satisfy the requirements of the g-2 experiment.
We propose to measure the rate \Rd\ for muon capture on the deuteron to better than 1.5% precisio... more We propose to measure the rate \Rd\ for muon capture on the deuteron to better than 1.5% precision. This process is the simplest weak interaction process on a nucleus that can both be calculated and measured to a high degree of precision. The measurement will provide a benchmark result, far more precise than any current experimental information on weak interaction processes in the two-nucleon system. Moreover, it can impact our understanding of fundamental reactions of astrophysical interest, like solar pp fusion and the $\nu+d$ reactions observed by the Sudbury Neutrino Observatory. Recent effective field theory calculations have demonstrated, that all these reactions are related by one axial two-body current term, parameterized by a single low-energy constant. Muon capture on the deuteron is a clean and accurate way to determine this constant. Once it is known, the above mentioned astrophysical, as well as other important two-nucleon reactions, will be determined in a model indepe...
WFD samples (2 ns each) 10 20 30 40 50 60 WFD ADC value 0 50 100 150 200 250 Waveform Digitizer t... more WFD samples (2 ns each) 10 20 30 40 50 60 WFD ADC value 0 50 100 150 200 250 Waveform Digitizer trace (a) Three pulses close together in one channel are easily distinguishable using waveform digitizers. (b) Online monitoring tools permit real time track-ing of observed muon decays as a function of time. Figure 1: The data sample of 8 × 10 10 muons collected in 2005 should yield a muon lifetime measurement with a statistical uncertainty of 4 ppm.
... (3) which is based on the 2008 summary of the standard model (SM) by de Rafael [3]. A ... one... more ... (3) which is based on the 2008 summary of the standard model (SM) by de Rafael [3]. A ... one can accept that QED is valid and use the electron anomaly to determine the most precise measurement of α, which de Rafael uses in his evaluation[3] of the QED contribution to aµ. 17 ...
The muLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muo... more The muLan experiment at the Paul Scherrer Institute will measure the lifetime of the positive muon with a precision of 1 ppm, giving a value for the Fermi coupling constant G_F at the level of 0.5 ppm. Meanwhile, by measuring the observed lifetime of the negative muon in pure hydrogen, the muCap experiment will determine the rate of muon capture, giving the proton's pseudoscalar coupling g_p to 7%. This coupling can be calculated precisely from heavy baryon chiral perturbation theory and therefore permits a test of QCD's chiral symmetry.
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Papers by Kevin Lynch