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Determination of the structure of {tau}decays in the reaction e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +} anti {nu}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} and a precision measurement of the {tau}-neutrino helicity

Technical Report:

Abstract

Using the ARGUS detector at the DORIS II storage ring we have investigated the Lorentz structure of the electroweak interaction in semi-hadronic {tau} decays. Spin correlations in the process e{sup +}e{sup -}{yields}{tau}{sup +}{tau}{sup -}{yields} anti {nu}{sub {tau}}{pi}{sup +}{pi}{sup 0} {nu}{sub {tau}}{pi}{sup -}{pi}{sup 0} are exploited for a measurement of the normalized product of the vector (g{sub V}) and axial vector (g{sub A}) couplings of the {tau} lepton, {gamma}{sub AV}=2 Re{l_brace}g{sub A}g{sub V}*{r_brace}/(vertical stroke g{sub V}vertical stroke {sup 2}+vertical stroke g{sub A}vertical stroke {sup 2}). The correlations are sensitive to the product of the couplings in both {tau} decays: {gamma}{sub AV}{sup 2}={gamma}{sub AV}({tau}{sup -}{yields}{nu}{sub {tau}}W{sup -}){gamma}{sub AV}({tau}{sup +}{yields} anti {nu}{sub {tau}}W{sup +}), which can be interpreted as the product of the neutrino helicities: {gamma}{sub AV}{sup 2}=-h({nu}{sub {tau}})h( anti {nu}{sub {tau}}). The measured value, {gamma}{sub AV}{sup 2}=1.044{+-}0.057{+-}0.060, determines the relative sign of the neutrino helicities. Assuming CP invariance, the absolute value {l_brace}{gamma}{sub AV}{r_brace}=1.022{+-}0.028{+-}0.030 was found to be in excellent agreement with the Standard Model. The contribution of scalar (g{sub S}) or pseudoscalar (g{sub P}) couplings was also investigated. No evidence for a scalar-like coupling was found. (orig.)
Publication Date:
Jul 01, 1994
Product Type:
Technical Report
Report Number:
DESY-94-120
Reference Number:
SCA: 662310; 662210; PA: DEN-94:0FM575; EDB-95:018008; SN: 95001305294
Resource Relation:
Other Information: PBD: Jul 1994
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ELECTRON-POSITRON INTERACTIONS; ANNIHILATION; TAU PARTICLES; SEMILEPTONIC DECAY; WEAK CHARGED CURRENTS; COUPLING CONSTANTS; AXIAL-VECTOR CURRENTS; HELICITY; TAU NEUTRINOS; PAIR PRODUCTION; RHO-770 MESONS; HADRONIC PARTICLE DECAY; PIONS PLUS; PIONS MINUS; PIONS NEUTRAL; CHARGED-CURRENT INTERACTIONS; GEV RANGE 01-10; GEV RANGE 10-100; ANGULAR CORRELATION; EXPERIMENTAL DATA; 662310; 662210; WEAK AND ELECTROMAGNETIC INTERACTIONS OF LEPTONS; UNIFIED THEORIES AND MODELS
OSTI ID:
10105607
Research Organizations:
Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
Country of Origin:
Germany
Language:
English
Other Identifying Numbers:
Journal ID: ISSN 0418-9833; Other: ON: DE95725959; TRN: DE94FM575
Availability:
OSTI; NTIS (US Sales Only); INIS
Submitting Site:
DEN
Size:
14 p.
Announcement Date:
Jun 30, 2005

Technical Report:

Citation Formats

Albrecht, H, Hamacher, T, Hofmann, R P, Kirchhoff, T, Mankel, R, Nau, A, Nowak, S, Ressing, D, Schroeder, H, Schulz, H D, Walter, M, Wurth, R, Hast, C, Kapitza, H, Kolanoski, H, Kosche, A, Lange, A, Lindner, A, Schieber, M, Siegmund, T, Spaan, B, Thurn, H, Toepfer, D, Wegener, D, Eckstein, P, Schmidtler, M, Schramm, M, Schubert, K R, Schwierz, R, Waldi, R, Reim, K, Wegener, H, Eckmann, R, Kuipers, H, Mai, O, Mundt, R, Oest, T, Reiner, R, Schmidt-Parzefall, W, Stiewe, J, Werner, S, Ehret, K, Hofmann, W, Huepper, A, Knoepfle, K T, Spengler, J, Krieger, P, MacFarlane, D B, Prentice, J D, Saull, P R.B., Tzamariudaki, K, Water, van de R.G., Yoon, T S, Frankl, C, Schneider, M, Weseler, S, Kernel, G, Krizan, P, Kriznic, E, Podobnik, T, Zivko, T, Balagura, V, Belyaev, I, Chechelnitsky, S, Danilov, M, Droutskoy, A, Gershtein, Yu, Golutvin, A, Korolko, I, Kostina, G, Litvintsev, D, Lubimov, V, Pakhlov, P, Semenov, S, Snizhko, A, Tichomirov, I, Zaitsev, Yu, and ARGUS Collaboration. Determination of the structure of {tau}decays in the reaction e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +} anti {nu}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} and a precision measurement of the {tau}-neutrino helicity. Germany: N. p., 1994. Web.
Albrecht, H, Hamacher, T, Hofmann, R P, Kirchhoff, T, Mankel, R, Nau, A, Nowak, S, Ressing, D, Schroeder, H, Schulz, H D, Walter, M, Wurth, R, Hast, C, Kapitza, H, Kolanoski, H, Kosche, A, Lange, A, Lindner, A, Schieber, M, Siegmund, T, Spaan, B, Thurn, H, Toepfer, D, Wegener, D, Eckstein, P, Schmidtler, M, Schramm, M, Schubert, K R, Schwierz, R, Waldi, R, Reim, K, Wegener, H, Eckmann, R, Kuipers, H, Mai, O, Mundt, R, Oest, T, Reiner, R, Schmidt-Parzefall, W, Stiewe, J, Werner, S, Ehret, K, Hofmann, W, Huepper, A, Knoepfle, K T, Spengler, J, Krieger, P, MacFarlane, D B, Prentice, J D, Saull, P R.B., Tzamariudaki, K, Water, van de R.G., Yoon, T S, Frankl, C, Schneider, M, Weseler, S, Kernel, G, Krizan, P, Kriznic, E, Podobnik, T, Zivko, T, Balagura, V, Belyaev, I, Chechelnitsky, S, Danilov, M, Droutskoy, A, Gershtein, Yu, Golutvin, A, Korolko, I, Kostina, G, Litvintsev, D, Lubimov, V, Pakhlov, P, Semenov, S, Snizhko, A, Tichomirov, I, Zaitsev, Yu, & ARGUS Collaboration. Determination of the structure of {tau}decays in the reaction e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +} anti {nu}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} and a precision measurement of the {tau}-neutrino helicity. Germany.
Albrecht, H, Hamacher, T, Hofmann, R P, Kirchhoff, T, Mankel, R, Nau, A, Nowak, S, Ressing, D, Schroeder, H, Schulz, H D, Walter, M, Wurth, R, Hast, C, Kapitza, H, Kolanoski, H, Kosche, A, Lange, A, Lindner, A, Schieber, M, Siegmund, T, Spaan, B, Thurn, H, Toepfer, D, Wegener, D, Eckstein, P, Schmidtler, M, Schramm, M, Schubert, K R, Schwierz, R, Waldi, R, Reim, K, Wegener, H, Eckmann, R, Kuipers, H, Mai, O, Mundt, R, Oest, T, Reiner, R, Schmidt-Parzefall, W, Stiewe, J, Werner, S, Ehret, K, Hofmann, W, Huepper, A, Knoepfle, K T, Spengler, J, Krieger, P, MacFarlane, D B, Prentice, J D, Saull, P R.B., Tzamariudaki, K, Water, van de R.G., Yoon, T S, Frankl, C, Schneider, M, Weseler, S, Kernel, G, Krizan, P, Kriznic, E, Podobnik, T, Zivko, T, Balagura, V, Belyaev, I, Chechelnitsky, S, Danilov, M, Droutskoy, A, Gershtein, Yu, Golutvin, A, Korolko, I, Kostina, G, Litvintsev, D, Lubimov, V, Pakhlov, P, Semenov, S, Snizhko, A, Tichomirov, I, Zaitsev, Yu, and ARGUS Collaboration. 1994. "Determination of the structure of {tau}decays in the reaction e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +} anti {nu}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} and a precision measurement of the {tau}-neutrino helicity." Germany.
@misc{etde_10105607,
title = {Determination of the structure of {tau}decays in the reaction e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} {yields} {rho}{sup +} anti {nu}{sub {tau}}{rho}{sup -}{nu}{sub {tau}} and a precision measurement of the {tau}-neutrino helicity}
author = {Albrecht, H, Hamacher, T, Hofmann, R P, Kirchhoff, T, Mankel, R, Nau, A, Nowak, S, Ressing, D, Schroeder, H, Schulz, H D, Walter, M, Wurth, R, Hast, C, Kapitza, H, Kolanoski, H, Kosche, A, Lange, A, Lindner, A, Schieber, M, Siegmund, T, Spaan, B, Thurn, H, Toepfer, D, Wegener, D, Eckstein, P, Schmidtler, M, Schramm, M, Schubert, K R, Schwierz, R, Waldi, R, Reim, K, Wegener, H, Eckmann, R, Kuipers, H, Mai, O, Mundt, R, Oest, T, Reiner, R, Schmidt-Parzefall, W, Stiewe, J, Werner, S, Ehret, K, Hofmann, W, Huepper, A, Knoepfle, K T, Spengler, J, Krieger, P, MacFarlane, D B, Prentice, J D, Saull, P R.B., Tzamariudaki, K, Water, van de R.G., Yoon, T S, Frankl, C, Schneider, M, Weseler, S, Kernel, G, Krizan, P, Kriznic, E, Podobnik, T, Zivko, T, Balagura, V, Belyaev, I, Chechelnitsky, S, Danilov, M, Droutskoy, A, Gershtein, Yu, Golutvin, A, Korolko, I, Kostina, G, Litvintsev, D, Lubimov, V, Pakhlov, P, Semenov, S, Snizhko, A, Tichomirov, I, Zaitsev, Yu, and ARGUS Collaboration}
abstractNote = {Using the ARGUS detector at the DORIS II storage ring we have investigated the Lorentz structure of the electroweak interaction in semi-hadronic {tau} decays. Spin correlations in the process e{sup +}e{sup -}{yields}{tau}{sup +}{tau}{sup -}{yields} anti {nu}{sub {tau}}{pi}{sup +}{pi}{sup 0} {nu}{sub {tau}}{pi}{sup -}{pi}{sup 0} are exploited for a measurement of the normalized product of the vector (g{sub V}) and axial vector (g{sub A}) couplings of the {tau} lepton, {gamma}{sub AV}=2 Re{l_brace}g{sub A}g{sub V}*{r_brace}/(vertical stroke g{sub V}vertical stroke {sup 2}+vertical stroke g{sub A}vertical stroke {sup 2}). The correlations are sensitive to the product of the couplings in both {tau} decays: {gamma}{sub AV}{sup 2}={gamma}{sub AV}({tau}{sup -}{yields}{nu}{sub {tau}}W{sup -}){gamma}{sub AV}({tau}{sup +}{yields} anti {nu}{sub {tau}}W{sup +}), which can be interpreted as the product of the neutrino helicities: {gamma}{sub AV}{sup 2}=-h({nu}{sub {tau}})h( anti {nu}{sub {tau}}). The measured value, {gamma}{sub AV}{sup 2}=1.044{+-}0.057{+-}0.060, determines the relative sign of the neutrino helicities. Assuming CP invariance, the absolute value {l_brace}{gamma}{sub AV}{r_brace}=1.022{+-}0.028{+-}0.030 was found to be in excellent agreement with the Standard Model. The contribution of scalar (g{sub S}) or pseudoscalar (g{sub P}) couplings was also investigated. No evidence for a scalar-like coupling was found. (orig.)}
place = {Germany}
year = {1994}
month = {Jul}
}