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Neutrino physics: Summary talk

Description: This paper is organized as follows: First, I describe the state of neutrino phenomenology. Emphasis is placed on sin/sup 2/ /theta//sub W/, its present status and future prospects. In addition, some signatures of ''new physics'' are described. Then, kaon physics at Fermilab is briefly discussed. I concentrate on the interesting rare decay K/sub L/ /yields/ /pi//sup 0/e/sup +/e/sup /minus// which may be a clean probe direct CP violation. Neutrino mass, mixing, and electromagnetic moments are surveyed. There, I describe the present state and future direction of accelerator based experiments. Finally, I conclude with an outlook on the future. Throughout this summary, I have drawn from and incorporated ideas discussed by other speakers at this workshop. However, I have tried to combine their ideas with my own perspective on neutrino physics and where it is headed. 49 refs., 3 figs., 4 tabs.
Date: April 1, 1989
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

KMC unitarity and K/sup +/ yields. pi. /sup +/. nu. anti. nu

Description: Experimental constraints on the Kobayashi-MaskawaCabibbo (KMC) matrix are surveyed and shown to provide a test of the standard model at the level of its O (..cap alpha..) radioactive corrections. The three generation prediction BR (K/sup +/ ..-->.. ..pi../sup +/..nu..) approx. = (0.35 approx. 3) x 10/sup 10/ is reviewed and the potential for enhancement up to approx. = 3 x 10/sup -9/ due to the fourth generation mixing is described. 19 refs.
Date: June 1, 1986
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

The standard model and beyond

Description: In these lectures, my aim is to present a status report on the standard model and some key tests of electroweak unification. Within that context, I also discuss how and where hints of new physics may emerge. To accomplish those goals, I have organized my presentation as follows. I survey the standard model parameters with particular emphasis on the gauge coupling constants and vector boson masses. Examples of new physics appendages are also commented on. In addition, I have included an appendix on dimensional regularization and a simple example which employs that technique. I focus on weak charged current phenomenology. Precision tests of the standard model are described and up-to-date values for the Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix parameters are presented. Constraints implied by those tests for a 4th generation, extra Z' bosons, and compositeness are discussed. An overview of the physics of tau decays is also included. I discuss weak neutral current phenomenology and the extraction of sin/sup 2//theta/W from experiment. The results presented there are based on a global analysis of all existing data. I have chosen to concentrate that discussion on radiative corrections, the effect of a heavy top quark mass, implications for grand unified theories (GUTS), extra Z' gauge bosons, and atomic parity violation. The potential for further experimental progress is also commented on. Finally, I depart from the narrowest version of the standard model and discuss effects of neutrino masses, mixings, and electromagnetic moments. 32 refs., 3 figs., 5 tabs
Date: May 1, 1989
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Proton decay: 1982

Description: Employing the current world average ..lambda../sub MS/ = 0.160 GeV as input, the minimal Georgi-Glashow SU(5) model predicts sin/sup 2/theta/sub W/(m/sub W/) = 0.214, m/sub b//m/sub tau/ approx. = 2.8 and tau/sub p/ approx. = (0.4 approx. 12) x 10/sup 29/ yr. The first two predictions are in excellent agreement with experiment; but the implied proton lifetime is already somewhat below the present experimental bound. In this status report, uncertainties in tau/sub p/ are described and effects of appendages to the SU(5) model (such as new fermion generations, scalars, supersymmetry, etc.) are examined.
Date: March 4, 1982
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Weak neutral currents and future Z mass measurements: Anticipating SLC

Description: The goals of this work are: to test the standard SU(2)/sub L/ x U(1) model at the tree and quantum loop level, provide a precise determination of sin/sup 2/ theta/sub W/ which could, for example, be used to rule out or at least constrain various grand unified theories (GUTS), and look for hints of ''new physics.'' The topics this paper elaborates on are radiative corrections, top quark mass bounds, grand unified theories (GUTS), and extra Z' boson constraints. In addition, the implications of a precise Z boson mass determination at SLC would have when combined with existing neutral current data is examined. 21 refs., 3 figs., 3 tabs. (LSP)
Date: September 1, 1987
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Standard model and beyond

Description: The ''standard'' SU(3)/sub C/ x SU(2)/sub L/ x U(1) model of strong and electroweak interactions elegantly incorporates all the proven symmetries and successes of the quark model, quantum electrodynamics, and the Four-Fermi theory. It correctly predicted weak neutral currents as well as the existence and properties of W/sup + -/, Z and gluons. ''Only'' the predicted Higgs scalar boson remains undiscovered. At this time there are no solid experimental results that cannot be accommodated by the standard model (at the 1 or 2 sigma level). Nevertheless, we do anticipate the emergence of new physics, beyond standard model expectations, which will hopefully provide guidance for theoretical advancement. Indeed, hints of some new phenomena may already be starting to appear in the CERN anti pp collider data. Details are discussed. 65 refs.
Date: January 1, 1985
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Proton decay theory

Description: Topics include minimal SU(5) predictions, gauge boson mediated proton decay, uncertainties in tau/sub p/, Higgs scalar effects, proton decay via Higgs scalars, supersymmetric SU(5), dimension 5 operators and proton decay, and Higgs scalars and proton decay. (WHK)
Date: January 1, 1983
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Electroweak interactions

Description: An overview of the 18 independent parameters of the standard SU(3)/sub c/ x SU(2)/sub L/ x U(1) model is given. Neutral current phenomenology and sin/sup 2/ theta/sub W/, W/sup +-/ and Z/sup 0/ masses, and testing the great desert hypothesis are discussed. The need for precise measurements in elementary particle physics is emphasized. (WHK)
Date: January 1, 1983
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Elementary particle theory

Description: The present state of the art in elementary particle theory is reviewed. Topics include quantum electrodynamics, weak interactions, electroweak unification, quantum chromodynamics, and grand unified theories. 113 references. (WHK)
Date: December 1, 1984
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Fermion masses and anomalous dipole moments

Description: Fermion mass generation via quantum loops is briefly described. The potential for large anomalous dipole moments, {delta}a{sub f} {approx_equal} m{sub f}{sup 2}/M{sup 2}, in such schemes is demonstrated. Implications for the muon`s anomalous magnetic moment as well as the top quark`s chromo and electroweak moments are discussed.
Date: August 1, 1995
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Radiative corrections and New Physics''

Description: Several pursuits of New Physics'' via precision measurements are surveyed. The inconsistency between tau lifetime-mass values and measured leptonic branching ratios is updated and a heavy fourth generation neutrino solution is described. Constraints on the Peskin-Takeushi S and T parameters are given. Consequences of low energy supersymmetry for grand unified theories are summarized. 15 refs., 1 tab.
Date: September 1, 1991
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Precision tests of electroweak theory

Description: Pursuits of New Physics'' via precision measurements are surveyed. The inconsistency between world average tau lifetime-mass values and measured leptonic branching ratios is updated and a heavy neutrino solution is described. The use of R{sub {tau}} {equivalent to} {Gamma}({tau} {yields} {nu}{sub {tau}} + hadrons)/{Gamma}({tau} {yields} e{bar {nu}}{sub e}{nu}{sub {tau}}) to determine {Lambda}{sub {ovr MS}} is discussed. Constraints on the Peskin-Takeuchi S and T parameters are given. Possible evidence for low energy supersymmetry from grand unified theories is scrutinized.
Date: March 1, 1992
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

A high energy physics perspective

Description: The status of the Standard model and role of symmetry in its development are reviewed. Some outstanding problems are surveyed and possible solutions in the form of additional {open_quotes}Hidden Symmetries {close_quotes} are discussed. Experimental approaches to uncover {open_quotes}New Physics{close_quotes} associated with those symmetries are described with emphasis on high energy colliders. An outlook for the future is given.
Date: January 13, 1997
Creator: Marciano, W. J.
Partner: UNT Libraries Government Documents Department

Higgs resonance studies at the First Muon Collider

Description: Higgs resonance signals and backgrounds at the First Muon Collider are discussed. Effects due to beam polarization and background angular distributions (forward-backward charge asymmetries) are examined. The utility of those features for improving precision measurements and narrow resonance ``discovery`` scans is described.
Date: December 1997
Creator: Kamal, B.; Marciano, W. J. & Parsa, Z.
Partner: UNT Libraries Government Documents Department

Resonant Higgs enhancement at the First Muon Collider

Description: The effect of beam polarization on Higgs resonance signals and backgrounds (b{anti b}, {tau}{anti {tau}}, c{anti c}) at the First Muon Collider is studied. Angular distributions (forward-backward charge asymmetries) are examined. The resulting effective enhancement of the Higgs signal relative to the background is investigated as is the reduction in scan time required for Higgs discovery.
Date: March 1, 1998
Creator: Kamal, B.; Marciano, W.J. & Parsa, Z.
Partner: UNT Libraries Government Documents Department

Kaon decays

Description: A survey of rare and not so rare kaon decays is presented. The role of such decays both in testing the standard model and searching for new physics'' is discussed. 37 refs., 2 tabs.
Date: January 1, 1989
Creator: Marciano, W.J. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

A theoretical perspective on neutrino physics

Description: A survey of sin{sup 2} {theta}{sub W}, {rho}, CKM matrix, and axial-isoscalar neutral current measurements via neutrino scattering is presented. Loop effects due to heavy top or a fourth generation are described. Neutrino oscillations are discussed in a three generation mixing framework and some motivation for {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillation searches is given. 15 refs., 1 tab.
Date: September 1, 1989
Creator: Marciano, W.J. (Brookhaven National Lab., Upton, NY (USA))
Partner: UNT Libraries Government Documents Department

Physics goals of the next linear collider

Description: We present the prospects for the next generation of high-energy physics experiments with electron-positron colliding beams. This report summarizes the current status of the design and technological basis of a linear collider of center of mass energy 500 GeV-1.5 TeV, and the opportunities for high-energy physics experiments that this machine is expected to open. 132 refs., 54 figs., 14 tabs.
Date: May 1, 1996
Creator: Kuhlman, S.; Marciano, W.J.; Gunion, J. F.; Group, NLC ZDR Design & Group, NLC Physics Working
Partner: UNT Libraries Government Documents Department

Letter of intent: a muon to electron conversion experiment at Fermilab

Description: We are writing this letter to express our interest in pursuing an experiment at Fermilab to search for neutrinoless conversion of muons into electrons in the field of a nucleus, which is a lepton flavor-violating (LFV) reaction. The sensitivity goal of this experiment represents an improvement of more than a factor of 10,000 over existing limits. It would provide the most sensitive test of LFV, a unique and essential window on new physics unavailable at the high energy frontier. We present a conceptual scheme that would exploit the existing Fermilab Accumulator and Debuncher rings to generate the required characteristics of the primary proton beam. The proposal requires only modest modifications to the accelerator complex beyond those already planned for the NOvA experiment, with which this experiment would be fully compatible; however, it could also benefit significantly from possible upgrades such as the 'Project X' linac. We include the conceptual design of the muon beam and the experimental apparatus, which use the previously proposed MECO experiment as a starting point.
Date: September 1, 2007
Creator: Carey, R.M.; Lynch, K.R.; Miller, J.P.; Roberts, B.L.; U., /Boston; Marciano, W.J. et al.
Partner: UNT Libraries Government Documents Department

Proposal to search for mu- N -> e- N with a single event sensitivity below 10 -16

Description: We propose a new experiment, Mu2e, to search for charged lepton flavor violation with unprecedented sensitivity. We will measure the ratio of the coherent neutrinoless conversion in the field of a nucleus of a negatively charged muon into an electron to the muon capture process: R{sub {mu}e} = {mu}{sup -} + A(Z,N) {yields} e{sup -} + A(Z,N)/{mu}{sup -} + A(Z,N) {yields} {nu}{sub {mu}} + A(Z-1, N), with a sensitivity R{sub {mu}e} {le} 6 x 10{sup -17} at 90% CL. This is almost a four order-of-magnitude improvement over the existing limit. The observation of such a process would be unambiguous evidence of physics beyond the Standard Model. Since the discovery of the muon in 1936, physicists have attempted to answer I.I. Rabi's famous question: 'Who ordered that?' Why is there a muon? What role does it play in the larger questions of why there are three families and flavors of quarks, leptons, and neutrinos? We know quarks mix through a mechanism described by the Cabbibo-Kobayashi-Maskawa matrix, which has been studied for forty years. Neutrino mixing has been observed in the last decade, but mixing among the family of charged leptons has never been seen. The current limits are of order 10{sup -11} - 10{sup -13} so the process is rare indeed. Why is such an experiment important and timely? A major motivation for experiments at the Large Hadron Collider (LHC) is the possible observation of supersymmetric particles in the TeV mass range. Many of these supersymmetric models predict a {mu}-e conversion signal at R{sub {mu}e} {approx} 10{sup -15}. We propose to search for {mu}-e conversion at a sensitivity that exceeds this by more than an order of magnitude. The LHC may not be able to conclusively distinguish among supersymmetric models, so Mu2e will provide invaluable information should the LHC observe a ...
Date: October 1, 2008
Creator: Carey, R.M.; Lynch, K.R.; Miller, J.P.; Roberts, B.L.; U., /Boston; Marciano, W.J. et al.
Partner: UNT Libraries Government Documents Department