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STUDIES OF THE RESONANCE INTEGRALS OF Re AND Tm. Monthly Progress Report, May 1, 1963-May 31, 1963

Description: The branching ratio for the beta decay of Tm/sup 170/ was determined to be 0.22 with an uncertainty of 2%, and the internal conversion coefficient of Yb/ sup 170/ was determined by two different methods to be 7.27 and 8.8 plus or minus 0.5, respectively. Preliminary work on resonance integral and reactivity measured is described. (D.C.W.)
Date: June 1, 1963
Creator: Zagotta, W.E.
Partner: UNT Libraries Government Documents Department

{epsilon}{prime}/{epsilon} and rare KL decays from KTeV Experiment

Description: The authors update the current status for the measurement of the direct-CP violation parameters {epsilon}{prime}/{epsilon} in the KTeV experiment at Fermilab. Substantial statistics have been accumulated during the 1996-7 run and 1999 run for both {epsilon}{prime}/{epsilon} and rare K{sub L} decay searches. The first KTeV result on {epsilon}{prime}/{epsilon} published last year was Re({epsilon}{prime}/{epsilon}) = (28.0 {+-} 4.1) x 10{sup {minus}4} based on the 23% data from 1996-7 run. Combining with the previous E731, NA31 and the recent preliminary NA48 results, the grand average is Re({epsilon}{prime}/{epsilon}) = (19.3 {+-} 3.6) x 10{sup {minus}4} (with S = 1:49), more than 5{sigma} above zero. More data from both KTeV and NA48 after completing the analysis will further improve the precision of this measurement in the near future and hopefully further improve the agreement. New results on the branching ratio and form factor measurements of K{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}} {gamma} using 1997 data are also presented. We find that BR(K{sub L} {r_arrow} {mu}{sup +} {mu}{sup {minus}} {gamma}) = (3.66 {+-} 0.04{sub stat} {+-} 0.07{sub syst}) x 10{sup {minus}7}. The form factor parameter {alpha}{sub K}* is measured to be {alpha}{sub K}* = {minus}0.157{sub {minus}0.027}{sup +0.025}. We make the first measurement of the parameter {alpha} from the D'Ambrosio, Isidori, and Portoles form factor, finding {alpha} = {minus}1.53 {+-} 0.09. This measurement of {alpha} limits the CKM parameter {rho} > {minus}0.2.
Date: January 16, 2001
Creator: Hsiung, Yee Bob
Partner: UNT Libraries Government Documents Department

Two RICH detectors as velocity spectrometers in the CKM experiment

Description: We present the design of two velocity spectrometers, to be used in the recently approved CKM experiment. CKM's main goal is the measurement of the branching ratio of K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} with a precision of 10%, via decays in flight of the K{sup +}. The design of both RICH detectors is based on the SELEX Phototube RICH. We will discuss the design and the expected performance, based on studies with SELEX data and Monte Carlo Simulations.
Date: September 4, 2002
Creator: al., Jurgen Engelfried et
Partner: UNT Libraries Government Documents Department

Branching ratios from B{sub s} and {Lambda}{sub b}{sup 0}

Description: CDF Run II relative branching ratio measurements for 65 pb{sup -1} of data in the channels B{sub s} {yields} D{sub s}{sup {-+}}{pi}{sup {-+}}, {Lambda} {sub b}{sup 0} {yields} {Lambda}{sub c}{sup {+-}}{pi}{sup {-+}} and B {yields} h{sup +}h{sup -} are presented. Further, an observation of B{sub s} {yields} K{sup {+-}} K{sup {-+}} and a measurement of A{sub CP} are presented.
Date: May 28, 2004
Creator: Martin, Matthew S.
Partner: UNT Libraries Government Documents Department

The CKM Experiment

Description: I describe the CKM experiment, a new initiative using the Fermilab Main Injector to obtain {approx} 100 events of the ultra-rare decay mode K{sup +} {yields} {pi}{sup +}{nu}{bar {nu}}. The branching ratio will be used to extract |V*{sub ts}V{sub td}|. Due to the decay mode's theoretical cleanliness, it plays a key role in over-constraining the Standard Model description of CP violation.
Date: October 25, 2002
Creator: Nguyen, Hogan H.
Partner: UNT Libraries Government Documents Department

MEASUREMENT OF B(K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}})

Description: The experimental measurement of K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}} is reviewed. New results from experiment E787 at BNL are presented: with data from 1995-97 the branching ratio has been measured to be B(K{sup +} {yields} {pi}{sup +} {nu}{bar {nu}}) = (1.5{sub {minus}1.2}{sup +3.4}) x 10{sup {minus}10}. The future prospects for additional data in this mode are examined.
Date: May 22, 2000
Creator: KETTELL,S.H.
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

Lepton flavor violation

Description: The connection of rare decays to supersymmetric grand unification is highlighted, and a review of the status of rare decay experiments is given. Plans for future investigations of processes that violate lepton flavor are discussed. A new result from the MEGA experiment, a search for {mu}{sup +} {yields} e{sup +} {gamma}, is reported to be B.R. < 3.8 x 10{sup -11} with 90% confidence.
Date: October 1, 1997
Creator: Cooper, M.D. Brooks, M. & Hogan, G.E.
Partner: UNT Libraries Government Documents Department

Review of alpha-decay data from doubly-even nuclei

Description: Alpha-decay data from doubly-even nuclei throughout the periodic table are reviewed and evaluated. From these data, nuclear radius parameters are calculated by using the Preston formula for {alpha}- decay probabilities. The radius parameters for each element behave rather regularly as a function of neutron number. The show minima at the major closed shells, increase sharply for parents just above the closed shells, and decrease smoothly toward the next shell closure. The same trend is observed for {alpha} reduced widths calculated using the Rasmussen formalism. Any irregularity or large departure from this behavior indicates probable incorrect input data. This systematic behavior can also be utilized to estimate partial half- lives.
Date: September 1, 1996
Creator: Akovali, Y.A.
Partner: UNT Libraries Government Documents Department

Radial and orbital q{anti q} excitations: ``Higher quarkonia``

Description: Identification of the spectrum of non-{ital q{anti q}} exotica such as glueballs, hybrids and molecules will require a detailed understanding of radially and orbitally excited quarkonia, since these states are a background to non-{ital q{anti q}} states. The data likely to become available experimentally on these higher-mass resonances are their total widths and strong branching fractions to dominant modes. We advocate the use of these branching fractions to distinguish quarkonia from exotica; in this contribution we summarize our recent detailed {sup 3}P{sub 0} decay model calculations of the 374 two-body open-flavor decay modes of the 32 lightest {ital n{anti n}} states above 1S and 1P, which should be useful for this program.
Date: December 31, 1996
Creator: Barnes, T.
Partner: UNT Libraries Government Documents Department

The K{sub L} {yields} {pi}{sup 0}{nu}{anti {nu}} decay beyond the Standard Model

Description: The K{sub L} {yields} {pi}{sup 0}{nu}{anti {nu}} decay is analyzed in a model independent way. When lepton flavor is conserved, this decay mode is a manifestation of CP violating interference between mixing and decay. Consequently, a theoretically clean relation between the measured rate and electroweak parameters holds in any given model.
Date: April 1, 1997
Creator: Grossman, Y.
Partner: UNT Libraries Government Documents Department

B Decay Studies at SLD

Description: We present three preliminary results from SLD on B decays: an inclusive search for the process b {r_arrow} s gluon, a measurement of the branching ratio for the process B {r_arrow} D{bar D}X, and measurements of the charged and neutral B lifetimes. All three measurements make use of the excellent vertexing efficiency and resolution of the CCD Vertex Detector and the first two make use of the excellent particle identification capability of the Cherenkov Ring Imaging Detector. The b {r_arrow} sg analysis searches for an enhancement of high momentum charged kaons produced in B decays. Within the context of a simple, Jetset-inspired model of b {r_arrow} sg, a limit of B(b {r_arrow} sg) &lt; 7.6% is obtained. The B(B {r_arrow} D{bar D}X) analysis reconstructs two secondary vertices and uses identified charged kaons to determine which of these came from charm decays. The result of the analysis is B(B {r_arrow} D{bar D}X) = (16.2 {+-} 1.9 {+-} 4.2)%. The results of the lifetime analysis are: {tau}{sub B{sup +}} = 1.686 {+-} 0.025 {+-} 0.042 ps, {tau}{sub B{sup 0}} = 1.589 {+-} 0.026 {+-} 0.055 ps and {tau}{sub B{sup +}}/{tau}{sub B{sup 0}} = 1.061 {+-} 0.031/0.029 {+-} 0.027.
Date: March 19, 1999
Creator: Convery, Mark R
Partner: UNT Libraries Government Documents Department

Towards a next-to-leading logarithmic result in B {r_arrow} X{sub s}{gamma}

Description: The calculation of the O ({alpha}{sub s}) virtual corrections to the matrix element of the inclusive decay b {r_arrow} s{gamma} is reported. These contributions drastically reduce the large renormalization scale dependence of the leading logarithmic calculation. Combining these results with the preliminary result for the Wilson coefficient C{sub {gamma}} (m{sub b}) calculated recently by Chetyrkin, Misiak, and Muenz, we estimate the branching ratio to be BR(B {r_arrow} X{sub s} {gamma}) = (3.25 {plus_minus} 0.50) x 10{sup {minus}4}.
Date: August 1, 1996
Creator: Greub, C. & Hurth, T.
Partner: UNT Libraries Government Documents Department

CDF results on B decays

Description: The authors present recent CDF results on B lifetimes, B meson mass measurements, ratios of branching ratios, and rare decays. In addition, they present the first measurement of time-dependent B{sub d} mixing at CDF. Several results have been updated and a few new ones included since the workshop.
Date: May 1995
Creator: Skarha, J. E.
Partner: UNT Libraries Government Documents Department

Bs physics and prospects at the Tevatron

Description: Both experiments CDF and D0 at the Tevatron collider have now the first samples of B{sub s} where preliminary measurements are performed. The mass and lifetime determination is shown and the yield for the hadronic B{sub s} decays, the first step towards the B{sub s} production fraction and Branching Ratio, is discussed. This also sets the bases for a re-evaluation of mixing capabilities in Run II.
Date: June 16, 2003
Creator: Lucchesi, D.
Partner: UNT Libraries Government Documents Department

Top Quark Production and Decay at the Tevatron

Description: Recent measurements of the top quark production cross section and decay properties by the CDF and D0 experiments are described. The cross section has been measured in dilepton, lepton plus jets, and all-hadronic final states, and a measurement of BR(t {yields} Wb)/BR(t {yields} Wq), where q is any quark, has been performed. The results, though statistics-limited, are consistent with each other and with theoretical predictions.
Date: May 1, 1997
Creator: Gerdes, D.W.
Partner: UNT Libraries Government Documents Department

Search for heavy neutral gauge bosons at D-Zero

Description: We report preliminary results of a search for a heavy neutral gauge boson, Z`, using the decay channel Z` {yields} ee . The data were collected with the D0 detector at the Fermilab Tevatron during the 1994-1995 p{anti p} collider run at {radical}s = 1.8 TeV and correspond to an integrated luminosity of {approx} 90 pb{sup -1}. Limits are set on the cross section times branching ratio for the process {anti p}p {yields} Z` {yields} ee as a function of the Z` mass. We exclude the existence of a heavy neutral gauge boson of mass less than 660 GeV/c{sup 2} (95% CL), assuming a Z` with the same coupling strengths to quarks and leptons as the standard model Z boson. Combining this analysis with DO`s 1992-1993 data set increases the limit to m{sub Z`} > 670 GeV/c{sup 2}.
Date: October 1, 1997
Creator: Abbott, B.
Partner: UNT Libraries Government Documents Department

Can we distinguish an MSSM higgs from a SM higgs at a linear collider?

Description: The authors study the prospects for distinguishing the CP-even Higgs boson of the minimal supersymmetric extension of the Standard Model (MSSM) from the Standard Model (SM) Higgs boson by measuring its branching ratios at an e{sup +}e{sup {minus}} linear collider. The regions of the M{sub A} - tan {beta} plane in which an MSSM Higgs boson can be distinguished from the SM Higgs boson depend strongly upon the supersymmetric parameters that enter the radiative corrections to the Higgs mass matrix and the Higgs couplings to fermions. In some regions of parameter space it is possible to extract the supersymmetric correction to the relation between the b quark mass and its Yukawa coupling from Higgs branching ratio measurements.
Date: January 4, 2001
Creator: Logan, H.E.
Partner: UNT Libraries Government Documents Department

Rare charm and B decays at CDF

Description: We present results on rare charm and B decays using 65pb{sup -1} of data taken with the CDF detector in Run II. Three results are discussed, a measurement of the relative branching ratios {Lambda}(D{sup 0} {yields} K{sup +}K{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and {Lambda}(D{sup 0} {yields} {pi}{sup +}{pi}{sup -})/{Lambda}(D{sup 0} {yields} K{pi}) and the direct CP-violating decay rate asymmetry, and a limit on the branching ratio of the FCNC decay D{sup 0} {yields} {mu}{sup +}{mu}{sup -}. We also discuss the prospects for the search for B{sub s}{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays.
Date: December 15, 2003
Creator: Thom, Julia
Partner: UNT Libraries Government Documents Department

Flavor changing kaon decays from hypercp: Measurements of the K+ ---&gt; pi+- mu+ mu- branching ratios

Description: The Fermilab HyperCP collaboration is making precision studies of charged hyperon and kaon decays, as well as searches for rare and forbidden hyperon and kaon decays. We report here on measurements of the branching ratios of the flavor-changing neutral-current decays: K{sup {+-}} {yields} {pi}{sup {+-}} {mu}{sup +} {mu}{sup -}, and compare our results to theoretical predictions. This is the first observation of the K{sup -} {yields} {pi}{sup -} {mu}{sup +} {mu}{sup -} decay.
Date: January 12, 2004
Creator: al., E. Craig Dukes et
Partner: UNT Libraries Government Documents Department

Charm physics at CDF II

Description: The CDF II detector has the capability of triggering on displaced tracks. Because of this ability, CDF II has accrued large samples of charged meson decays to fully hadronic final states in 64 pb{sup -1} of p{bar p} collision data gathered at {radical}s = 1.96 TeV. Using initial Run II data samples, the production cross sections for J/{psi}, D{sup 0}, D{sup +}, D*{sup +} and D{sub s}{sup +} mesons have been measured. Ratios of branching ratios for Cabibbo suppressed final states and CP asymmetries in D{sup 0} meson decays have been studied. A measurement of the mass difference m(D{sub s}{sup +}) -m(D{sup +}) has been done, and a limit for the branching fraction of the FCNC D{sup 0} {yields} {mu}{sup +}{mu}{sup -} decays has been set.
Date: October 28, 2003
Creator: Furic, I.
Partner: UNT Libraries Government Documents Department

CKM--Charged Kaons at the Main Injector

Description: The CKM experiment is a proposal to measure the branching ratio of the rare decay K{sup +} {r_arrow} {pi}{sup +} {nu}{bar {nu}} at the Main Injector at Fermilab using a decay in flight technique. The goal is to observe {approx}100 events, for a Standard Model branching ratio of 1 x 10{sup {minus}10} with a background of less than 10 events.
Date: January 16, 2001
Creator: Cooper, P.S.
Partner: UNT Libraries Government Documents Department

A general algorithm for radioactive decay with branching and loss from a medium

Description: Many areas in the field of health physics require evaluation of the change of radionuclide quantity in a medium with time. A general solution to first-order compartmental models is presented in this paper for application to systems consisting of one physical medium that contains any number of radionuclide decay chain members. The general analytical solution to the problem is first described mathematically, and then extended to four applications: (1) evaluation of the quantity of radionuclides as a function of time, (2) evaluation of the time integral of the quantity during a time period, (3) evaluation of the amount in a medium as a function of time following deposition at a constant rate, and (4) evaluation of the time integral of the amount in a medium after deposition at a constant rate for a time. The solution can be applied to any system involving physical transfers from the medium and radioactive chain decay with branching in the medium. The general solution is presented for quantities expressed in units of atoms and activity. Unlike many earlier mathematical solutions, this solution includes chain decay with branching explicitly in the equations.
Date: July 1, 1995
Creator: Strenge, D.L.
Partner: UNT Libraries Government Documents Department