arXiv subjects
Publications and source records attributed to W. Marciano.
We discuss the prospects for improving the precision on the hadronic corrections to the anomalous magnetic moment of the muon, and the plans of the Muon $g-2$ Theory Initiative to update the Standard Model prediction.
This document represents the response of the Intensity Frontier Neutrino Working Group to the Snowmass charge. We summarize the current status of neutrino physics and identify many exciting future opportunities for studying the properties of neutrinos and for addressing important physics and astrophysics questions with neutrinos.
This report provides the results of an extensive and important study of the potential for a U.S. scientific program that will extend our knowledge of neutrino oscillations well beyond what can be anticipated from ongoing and planned experiments worldwide. The program examined here has the potential to provide the U.S. particle physics community with world leading experimental capability in this intensely interesting and active field of fundamental research. Furthermore, this capability could be unique compared to anywhere else in the world because of the available beam intensity and baseline distances. The present study was initially commissioned in April 2006 by top research officers of Brookhaven National Laboratory and Fermi National Accelerator Laboratory and, as the study evolved, it also provided responses to questions formulated and addressed to the study group by the Neutrino Scientific Advisory Committee (NuSAG) of the U.S. DOE and NSF. The participants in the study, its Charge and history, plus the study results and conclusions are provided in this report and its appendices. A summary of the conclusions is provided in the Executive Summary.
This report is intended to describe first, the principal physics reasons for an ambitious experimental program in neutrino physics and proton decay based on construction of a series of massive water Cherenkov detectors located deep underground (4850 ft) in the Homestake Mine of the South Dakota Science and Technology Authority (SDSTA); and second, the engineering design of the underground chambers to house the Cherenkov detector modules; and third, the conceptual design of the water Cherenkov detectors themselves for this purpose. Included in this document are preliminary costs and time-to-completion estimates which have been exposed to acknowledged experts in their respective areas. We have included some contingency factors. Nevertheless, we recognize that much more extensive documentation and contingency estimates will be needed for a full technical design report. In this proposal we show the event rates and physics sensitivity for beams from both FNAL (1300 km distant from Homestake) and BNL (2540 km distant from Homestake). The program we propose will benefit from a beam from FNAL because of the high intensities currently available from the Main Injector with modest upgrades. The possibility of tuning the primary proton energy over a large range from 30 to 120 GeV also adds considerable flexibility to the program from FNAL.
We review the recent experimental and theoretical progress in the determination of |V_{ud}| and |V_{us}|, and the status of the most stringent test of CKM unitarity. Future prospects on |V_{cd}| and |V_{cs}| are also briefly discussed.
This is a preliminary version of a formal proposal by the 3M collaboration to construct a megaton, modular, multipurpose (3M) neutrino detector for a program of experiments in neutrino physics. The detector components will be located in chambers approximately 7000 ft below the Earth's surface in the Homestake Mine at Lead, South Dakota, to carry out experiments on neutrino oscillations directed toward the principal experimental goal of the program, viz., the issue of CP-invariance violation in the lepton sector of elementary particles, an issue that has been the subject of study in the quark sector for several decades. The principal physics goal of this program also requires a moderately intense neutrino beam from an accelerator located a long distance from the detector array, such as the 2540 km distance of BNL from Homestake. The construction plan for that neutrino beam is at http://nwg.phy.bnl.gov/. Other experimental searches that do not require the accelerator-generated beam can be carried out with the 3M detector independently of and at the same time as the neutrino oscillation and CP-invariance violation measurements are in progress. They are searches for Proton Decay, UHE Neutrinos, and Supernovae Neutrinos.
We analyze the prospects of a feasible, Brookhaven National Laboratory based, very long baseline (BVLB) neutrino oscillation experiment consisting of a conventional horn produced low energy wide band beam and a detector of 500 kT fiducial mass with modest requirements on event recognition and resolution. Such an experiment is intended primarily to determine CP violating effects in the neutrino sector for 3-generation mixing. We analyze the sensitivity of such an experiment. We conclude that this experiment will allow determination of the CP phase $δ_{CP}$ and the currently unknown mixing parameter $θ_{13}$, if $\sin ^2 2 θ_{13} \geq 0.01$, a value $\sim 15$ times lower than the present experimental upper limit. In addition to $θ_{13}$ and $δ_{CP}$, the experiment has great potential for precise measurements of most other parameters in the neutrino mixing matrix including $Δm^2_{32}$, $\sin^2 2θ_{23}$, $Δm^2_{21}\times \sin 2 θ_{12}$, and the mass ordering of neutrinos through the observation of the matter effect in the $ν_μ\to ν_e$ appearance channel.
We report on the status and plans of experiments now running or proposed for electron-positron colliders at energies between the $ϕ$ and the Z. The $e^{+}e^{-}$ B and charm factories we considered were PEP-II/BABAR, KEKB/Belle, superKEK, SuperBABAR, and CESR-c/CLEO-c. We reviewed the programs at the $ϕ$ factory at Frascati and the proposed PEP-N facility at Stanford Linear Accelerator Center. We studied the prospects for B physics with a dedicated linear collider Z factory, associated with the TESLA high energy linear collider. In all cases, we compared the physics reach of these facilities with that of alternative experiments at hadron colliders or fixed target facilities.
In the first part of this report, we discuss the prospects for measuring the W mass and width in Run II. The basic techniques used to measure M_W are described and the statistical, theoretical and detector-related uncertainties are discussed in detail. Alternative methods of measuring the W mass at the Tevatron and the prospects for M_W measurements at other colliders are also described. In the second part, we discuss the measurement of the forward backward asymmetry in Drell Yan production in Run II which can be used to determine the effective weak mixing angle. Estimates of the statistical and systematic uncertainties in Run II are given. The third part summarizes the features of the FORTRAN package GAPP which performs a fit to the electroweak observables and extracts the probability distribution function of the Higgs boson mass.
We consider the search for the Higgs boson at a high-luminosity Fermilab Tevatron, an upgraded Tevatron of energy 3.5 TeV, and the CERN Large Hadron Collider, via $WH/ZH$ production followed by H -> bb~ and leptonic decay of the weak vector bosons. We show that each of these colliders can potentially observe the standard Higgs boson in the intermediate-mass range, 80 GeV γγat the LHC. In addition, it can potentially be used to observe the lightest Higgs scalar of the minimal supersymmetric model in a region of parameter space not accessible to CERN LEP II or the LHC (using h -> γγ,ZZ^*).
The Wjj background has increased by 70%. This decreases the significance of the WH signal somewhat. The significance of the ZH signal remains about the same.