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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

THE WEAK MIXING ANGLE AND NEW PHYSICS (A TALE OF TWO NUMBERS)

Description: The two best Z pole determinations of sin{sup 2} {theta}{sub W} (m{sub z}){sub {ovr MS}} differ by 3 sigma, a feature lost in global fits and averaging. Individually, sin{sup 2} {theta}{sub W}(m{sub Z}){sub {ovr MS}} = 0.2307(3) obtained from A{sub LR}, taken together with m{sub W} = 80.410(32) GeV, points to a very light Higgs boson, m{sub H} {approx_equal} 12-63 GeV, already ruled out experimentally. it is, however, easily redeemed by low mass scale supersymmetry or models with (effectively) S {approx_equal} -0.12 and T {approx_equal} +0.06. Alternatively, sin{sup 2} {theta}{sub W} (m{sub Z}){sub {ovr MS}} {approx_equal} 0.2320(3) obtained from A{sub FB}(Z {yields} {ovr bb}), suggests a very heavy Higgs, m{sub H} {approx} 500 GeV, along with S {approx_equal} +0.45 which is suggestive of Technicolor models. Future ways to resolve this discrepancy are briefly discussed.
Date: May 30, 2006
Creator: MARCIANO, W.
Partner: UNT Libraries Government Documents Department

ELECTROWEAK PHYSICS AND PRECISION STUDIES.

Description: The utility of precision electroweak measurements for predicting the Standard Model Higgs mass via quantum loop effects is discussed. Current values of m{sub W}, sin{sup 2} {theta}{sub W}(m{sub Z}){sub {ovr MS}} and m{sub t} imply a relatively light Higgs which is below the direct experimental bound but possibly consistent with Supersymmetry expectations. The existence of Supersymmetry is further suggested by a 2{sigma} discrepancy between experiment and theory for the muon anomalous magnetic moment. Constraints from precision studies on other types of ''New Physics'' are also briefly described.
Date: October 24, 2005
Creator: MARCIANO, W.
Partner: UNT Libraries Government Documents Department

INTENSE NEUTRINO BEAMS AND LEPTONIC CP VIOLATION.

Description: Effects of the Leptonic CP violating phase, {delta}, on 3 generation neutrino oscillation rates and asymmetries are discussed. A figure of merit argument is used to show that our ability to measure the phase 6 is rather insensitive to the value of {theta}{sub 13} (for sin{sup 2} 2{theta}{sub 13} {approx}> 0.01) as well as the detector distance (for very long oscillation baselines). Using a study of {nu}{sub {mu}} {yields} {nu}{sub e} oscillations for BNL-Homestake (2540 km) we show that a conventional horn focused wide band neutrino beam generated by an intense 1-2 MW proton source combined with a very large water Cherenkov detector (250-500 kton) should be able to determine {delta} to about {+-}15{sup o} in 5 x 10{sup 7} sec. of running. In addition, such an effort would also measure the other oscillation parameters ({theta}{sub ij}, {Delta}m{sub ij}{sup 2}) with high precision. Similar findings apply to a Fermilab-Homestake (1280 km) baseline. We also briefly discuss features of Superbeams, Neutrino Factories and Beta-Beams.
Date: June 13, 2006
Creator: MARCIANO, W. & PARSA, Z.
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

Future search for grand unified theory magnetic monopoles

Description: After a brief discussion of the theoretical notation, we discuss the present experimental limits and experimental techniques in the search for very massive magnetic monopoles. We attempt to survey possible future experiments and the limits of the experimental techniques with emphasis on the type of R and D that will be useful in these searches.
Date: January 1, 1982
Creator: Ayres, D.; Cline, D.; Heller, K.; Marciano, W. & Shrock, R.
Partner: UNT Libraries Government Documents Department

Long-Range Lepton Flavor Interactions and Neutrino Oscillations

Description: Recent results from the MINOS accelerator neutrino experiment suggest a possible difference between {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance oscillation parameters, which one may ascribe to a new long distance potential acting on neutrinos. As a specific example, we consider a model with gauged B - L{sub e} - 2L{sub {tau}} number which contains an extremely light new vector boson, m{sub Z}, < 10{sup -18} eV and extraordinarily weak coupling {alpha}{prime} {approx}< 10{sup -52}. In that case, differences between {nu}{sub {mu}} {yields} {nu}{sub {tau}} and {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub {tau}} oscillations can result from a long-range potential due to neutrons in the Earth and the Sun that distinguishes {nu}{sub {mu}} and {nu}{sub {tau}} on Earth, with a potential difference of {approx} 6 x 10{sup -14} eV, and changes sign for anti-neutrinos. We show that existing solar, reactor, accelerator, and atmospheric neutrino oscillation constraints can be largely accommodated for values of parameters that help explain the possible MINOS anomaly by this new physics, although there is some tension with atmospheric constraints. A long-range interaction, consistent with current bounds, could have very pronounced effects on atmospheric neutrino disappearance in the 20-50 GeV range that will be studied with the IceCube DeepCore array, currently in operation, and can have a significant effect on future high-precision long-baseline oscillation experiments which aim for {+-}1% sensitivity, in {nu}{sub {mu}} and {bar {nu}}{sub {mu}} disappearance, separately. Together, these experiments can extend the reach for new long-distance effects well beyond current bounds and test their relevance to the aforementioned MINOS anomaly. We also point out that long-range potentials originating from the Sun could lead to annual modulations of neutrino data at the percent level, due to the variation of the Earth-Sun distance. A similar phenomenology is shown to apply to other potential new gauge symmetries ...
Date: March 31, 2011
Creator: Davoudiasl, H.; Lee, H-S & Marciano, W.
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

AGS SUPER NEUTRINO BEAM FACILITY ACCELERATOR AND TARGET SYSTEM DESIGN (NEUTRINO WORKING GROUP REPORT-II).

Description: This document describes the design of the accelerator and target systems for the AGS Super Neutrino Beam Facility. Under the direction of the Associate Laboratory Director Tom Kirk, BNL has established a Neutrino Working Group to explore the scientific case and facility requirements for a very long baseline neutrino experiment. Results of a study of the physics merit and detector performance was published in BNL-69395 in October 2002, where it was shown that a wide-band neutrino beam generated by a 1 MW proton beam from the AGS, coupled with a half megaton water Cerenkov detector located deep underground in the former Homestake mine in South Dakota would be able to measure the complete set of neutrino oscillation parameters: (1) precise determination of the oscillation parameters {Delta}m{sub 32}{sup 2} and sin{sup 2} 2{theta}{sub 32}; (2) detection of the oscillation of {nu}{sub {mu}}-{nu}{sub e} and measurement of sin{sup 2} 2{theta}{sub 13}; (3) measurement of {Delta}m{sub 21}{sup 2} sin 2{theta}{sub 12} in a {nu}{sub {mu}} {yields} {nu}{sub e} appearance mode, independent of the value of {theta}{sub 13}; (4) verification of matter enhancement and the sign of {Delta}m{sub 32}{sup 2}; and (5) determination of the CP-violation parameter {delta}{sub CP} in the neutrino sector. This report details the performance requirements and conceptual design of the accelerator and the target systems for the production of a neutrino beam by a 1.0 MW proton beam from the AGS. The major components of this facility include a new 1.2 GeV superconducting linac, ramping the AGS at 2.5 Hz, and the new target station for 1.0 MW beam. It also calls for moderate increase, about 30%, of the AGS intensity per pulse. Special care is taken to account for all sources of proton beam loss plus shielding and collimation of stray beam halo particles to ensure equipment reliability and ...
Date: April 21, 2003
Creator: DIWAN,M.; MARCIANO,W.; WENG,W. & RAPARIA,D.
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