Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X)

R. Akers, G. Alexander, J. Allison, N. Altekamp, K. Ametewee, K. J. Anderson, S. Anderson, S. Arcelli, S. Asai, D. Axen, G. Azuelos, A. H. Ball, E. Barberio, R. J. Barlow, R. Bartoldus, J. R. Batley, G. Beaudoin, J. Bechtluft, A. Beck, G. A. BeckC. Beeston, T. Behnke, K. W. Bell, G. Bella, S. Bentvelsen, P. Berlich, S. Bethke, O. Biebel, I. J. Bloodworth, P. Bock, H. M. Bosch, M. Boutemeur, S. Braibant, P. Bright-Thomas, R. M. Brown, A. Buijs, H. J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, C. Charlesworth, D. G. Charlton, S. L. Chu, P. E.L. Clarke, J. C. Clayton, S. G. Clowes, I. Cohen, J. E. Conboy, O. C. Cooke, M. Cuffiani, S. Dado, C. Dallapiccola, G. M. Dallavalle, C. Darling, S. De Jong, L. A. Del Pozo, H. Deng, M. S. Dixit, E. Do Couto E Silva, J. E. Duboscq, E. Duchovni, G. Duckeck, I. P. Duerdoth, U. C. Dunwoody, J. E.G. Edwards, P. G. Estabrooks, H. G. Evans, F. Fabbri, B. Fabbro, M. Fanti, P. Fath, F. Fiedler, M. Fierro, M. Fincke-Keeler, H. M. Fischer, R. Folman, D. G. Fong, M. Foucher, H. Fukui, A. Fürtjes, P. Gagnon, A. Gaidot, J. W. Gary, J. Gascon, S. M. Gascon-Shotkin, N. I. Geddes, C. Geich-Gimbel, S. W. Gensler, F. X. Gentit, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W. R. Gibson, J. D. Gillies, D. M. Gingrich, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, E. Gross, G. G. Hanson, M. Hansroul, M. Hapke, C. K. Hargrove, P. A. Hart, C. Hartmann, M. Hauschild, C. M. Hawkes, R. Hawkings, R. J. Hemingway, G. Herten, R. D. Heuer, J. C. Hill, S. J. Hillier, T. Hilse, P. R. Hobson, D. Hochman, R. J. Homer, A. K. Honma, R. Howard, R. E. Hughes-Jones, D. E. Hutchcroft, P. Igo-Kemenes, D. C. Imrie, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, M. Jones, R. W.L. Jones, P. Jovanovic, J. Kanzaki, D. Karlen, K. Kawagoe, T. Kawamoto, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, B. J. King, J. King, J. Kirk, S. Kluth, T. Kobayashi, M. Kobel, D. S. Koetke, T. P. Kokott, Sachio Komamiya, R. Kowalewski, T. Kress, P. Krieger, J. Von Krogh, P. Kyberd, G. D. Lafferty, H. Lafoux, R. Lahmann, W. P. Lai, D. Lanske, J. Lauber, J. G. Layter, A. M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, S. L. Lloyd, F. K. Loebinger, G. D. Long, B. Lorazo, M. J. Losty, J. Ludwig, A. Luig, A. Malik, M. Mannelli, S. Marcellini, C. Markus, A. J. Martin, J. P. Martin, T. Mashimo, W. Matthews, P. Mättig, J. McKenna, E. A. Mckigney, T. J. McMahon, A. I. McNab, F. Meijers, S. Menke, F. S. Merritt, H. Mes, A. Michelini, G. Mikenberg, D. J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, M. Morii, U. Müller, B. Nellen, B. Nijjhar, S. W. O'Neale, F. G. Oakham, F. Odorici, H. O. Ogren, N. J. Oldershaw, C. J. Oram, M. J. Oreglia, S. Orito, F. Palmonari, J. P. Pansart, G. N. Patrick, M. J. Pearce, P. D. Phillips, J. E. Pilcher, J. Pinfold, D. E. Plane, P. Poffenberger, B. Poli, A. Posthaus, T. W. Pritchard, H. Przysiezniak, M. W. Redmond, D. L. Rees, D. Rigby, M. G. Rison, S. A. Robins, N. Rodning, J. M. Roney, E. Ros, A. M. Rossi, M. Rosvick, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, D. R. Rust, M. Sasaki, C. Sbarra, A. D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, P. Schenk, B. Schmitt, M. Schröder, H. C. Schultz-Coulon, M. Schulz, P. Schütz, J. Schwiening, W. G. Scott, M. Settles, T. G. Shears, B. C. Shen, C. H. Shepherd-Themistocleous, P. Sherwood, G. P. Siroli, A. Skillman, A. Skuja, A. M. Smith, T. J. Smith, G. A. Snow, R. Sobie, S. Söldner-Rembold, R. W. Springer, M. Sproston, A. Stahl, M. Starks, C. Stegmann, K. Stephens, J. Steuerer, B. Stockhausen, D. Strom, P. Szymanski, R. Tafirout, P. Taras, S. Tarem, M. Tecchio, P. Teixeira-Dias, N. Tesch, M. A. Thomson, E. Von Törne, S. Towers, M. Tscheulin, T. Tsukamoto, A. S. Turcot, M. F. Turner-Watson, P. Utzat, R. Van Kooten, G. Vasseur, P. Vikas, M. Vincter, F. Wäckerle, A. Wagner, D. L. Wagner, C. P. Ward, D. R. Ward, J. J. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, P. Weber, P. S. Wells, N. Wermes, B. Wilkens, G. W. Wilson, J. A. Wilson, T. Wlodek, G. Wolf, S. Wotton, T. R. Wyatt, G. Yekutieli, V. Zacek, W. Zeuner, G. T. Zorn

Research output: Contribution to journalArticle

40 Citations (Scopus)

Abstract

The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990 and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce a Λ baryon are identified through the correlation of the baryon number of the Λ and the electric charge of the lepton. To measure the lifetime, the decay point of the b baryon is estimated by the Λ-lepton vertex, and the observed distribution of decay lengths is fitted simultaneously in 874 right-sign and 384 wrong-sign combinations. In a separate method, the impact parameter distribution of the leptons is fitted in a subset of these data. When the two results are combined, taking correlations into account, the average b-baryon lifetime is found to be τ = 1.16 ± 0.11 (stat.) ± 0.06 (syst.) ps. Using the same data, the product branching ratio is measured to be f(b → Δb)·BR(Λb → Λℓ-ν̄X) = (2.91 ± 0.23 (stat.) ±0.25 (syst.))·10-3, where the symbol f(b → Λb) is the fraction of b quarks from Z0 decays forming b baryons, Λb represents all b-flavoured baryons and ℓ is either an electron or a muon.

Original languageEnglish
Pages (from-to)195-214
Number of pages20
JournalZeitschrift fur Physik C-Particles and Fields
Volume69
Issue number2
Publication statusPublished - 1996 Jan 1
Externally publishedYes

Fingerprint

Electric charge
baryons
Detectors
life (durability)
Electrons
products
leptons
decay
electric charge
set theory
muons
apexes
quarks
detectors

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Akers, R., Alexander, G., Allison, J., Altekamp, N., Ametewee, K., Anderson, K. J., ... Zorn, G. T. (1996). Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X). Zeitschrift fur Physik C-Particles and Fields, 69(2), 195-214.

Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X). / Akers, R.; Alexander, G.; Allison, J.; Altekamp, N.; Ametewee, K.; Anderson, K. J.; Anderson, S.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Ball, A. H.; Barberio, E.; Barlow, R. J.; Bartoldus, R.; Batley, J. R.; Beaudoin, G.; Bechtluft, J.; Beck, A.; Beck, G. A.; Beeston, C.; Behnke, T.; Bell, K. W.; Bella, G.; Bentvelsen, S.; Berlich, P.; Bethke, S.; Biebel, O.; Bloodworth, I. J.; Bock, P.; Bosch, H. M.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brown, R. M.; Buijs, A.; Burckhart, H. J.; Burgard, C.; Bürgin, R.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlesworth, C.; Charlton, D. G.; Chu, S. L.; Clarke, P. E.L.; Clayton, J. C.; Clowes, S. G.; Cohen, I.; Conboy, J. E.; Cooke, O. C.; Cuffiani, M.; Dado, S.; Dallapiccola, C.; Dallavalle, G. M.; Darling, C.; De Jong, S.; Del Pozo, L. A.; Deng, H.; Dixit, M. S.; Do Couto E Silva, E.; Duboscq, J. E.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Dunwoody, U. C.; Edwards, J. E.G.; Estabrooks, P. G.; Evans, H. G.; Fabbri, F.; Fabbro, B.; Fanti, M.; Fath, P.; Fiedler, F.; Fierro, M.; Fincke-Keeler, M.; Fischer, H. M.; Folman, R.; Fong, D. G.; Foucher, M.; Fukui, H.; Fürtjes, A.; Gagnon, P.; Gaidot, A.; Gary, J. W.; Gascon, J.; Gascon-Shotkin, S. M.; Geddes, N. I.; Geich-Gimbel, C.; Gensler, S. W.; Gentit, F. X.; Geralis, T.; Giacomelli, G.; Giacomelli, P.; Giacomelli, R.; Gibson, V.; Gibson, W. R.; Gillies, J. D.; Gingrich, D. M.; Goldberg, J.; Goodrick, M. J.; Gorn, W.; Grandi, C.; Gross, E.; Hanson, G. G.; Hansroul, M.; Hapke, M.; Hargrove, C. K.; Hart, P. A.; Hartmann, C.; Hauschild, M.; Hawkes, C. M.; Hawkings, R.; Hemingway, R. J.; Herten, G.; Heuer, R. D.; Hill, J. C.; Hillier, S. J.; Hilse, T.; Hobson, P. R.; Hochman, D.; Homer, R. J.; Honma, A. K.; Howard, R.; Hughes-Jones, R. E.; Hutchcroft, D. E.; Igo-Kemenes, P.; Imrie, D. C.; Jawahery, A.; Jeffreys, P. W.; Jeremie, H.; Jimack, M.; Joly, A.; Jones, M.; Jones, R. W.L.; Jovanovic, P.; Kanzaki, J.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; King, B. J.; King, J.; Kirk, J.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D. S.; Kokott, T. P.; Komamiya, Sachio; Kowalewski, R.; Kress, T.; Krieger, P.; Von Krogh, J.; Kyberd, P.; Lafferty, G. D.; Lafoux, H.; Lahmann, R.; Lai, W. P.; Lanske, D.; Lauber, J.; Layter, J. G.; Lee, A. M.; Lefebvre, E.; Lellouch, D.; Letts, J.; Levinson, L.; Lloyd, S. L.; Loebinger, F. K.; Long, G. D.; Lorazo, B.; Losty, M. J.; Ludwig, J.; Luig, A.; Malik, A.; Mannelli, M.; Marcellini, S.; Markus, C.; Martin, A. J.; Martin, J. P.; Mashimo, T.; Matthews, W.; Mättig, P.; McKenna, J.; Mckigney, E. A.; McMahon, T. J.; McNab, A. I.; Meijers, F.; Menke, S.; Merritt, F. S.; Mes, H.; Michelini, A.; Mikenberg, G.; Miller, D. J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Morii, M.; Müller, U.; Nellen, B.; Nijjhar, B.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Ogren, H. O.; Oldershaw, N. J.; Oram, C. J.; Oreglia, M. J.; Orito, S.; Palmonari, F.; Pansart, J. P.; Patrick, G. N.; Pearce, M. J.; Phillips, P. D.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poffenberger, P.; Poli, B.; Posthaus, A.; Pritchard, T. W.; Przysiezniak, H.; Redmond, M. W.; Rees, D. L.; Rigby, D.; Rison, M. G.; Robins, S. A.; Rodning, N.; Roney, J. M.; Ros, E.; Rossi, A. M.; Rosvick, M.; Routenburg, P.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D. R.; Sasaki, M.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schenk, P.; Schmitt, B.; Schröder, M.; Schultz-Coulon, H. C.; Schulz, M.; Schütz, P.; Schwiening, J.; Scott, W. G.; Settles, M.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Skillman, A.; Skuja, A.; Smith, A. M.; Smith, T. J.; Snow, G. A.; Sobie, R.; Söldner-Rembold, S.; Springer, R. W.; Sproston, M.; Stahl, A.; Starks, M.; Stegmann, C.; Stephens, K.; Steuerer, J.; Stockhausen, B.; Strom, D.; Szymanski, P.; Tafirout, R.; Taras, P.; Tarem, S.; Tecchio, M.; Teixeira-Dias, P.; Tesch, N.; Thomson, M. A.; Von Törne, E.; Towers, S.; Tscheulin, M.; Tsukamoto, T.; Turcot, A. S.; Turner-Watson, M. F.; Utzat, P.; Van Kooten, R.; Vasseur, G.; Vikas, P.; Vincter, M.; Wäckerle, F.; Wagner, A.; Wagner, D. L.; Ward, C. P.; Ward, D. R.; Ward, J. J.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Weber, P.; Wells, P. S.; Wermes, N.; Wilkens, B.; Wilson, G. W.; Wilson, J. A.; Wlodek, T.; Wolf, G.; Wotton, S.; Wyatt, T. R.; Yekutieli, G.; Zacek, V.; Zeuner, W.; Zorn, G. T.

In: Zeitschrift fur Physik C-Particles and Fields, Vol. 69, No. 2, 01.01.1996, p. 195-214.

Research output: Contribution to journalArticle

Akers, R, Alexander, G, Allison, J, Altekamp, N, Ametewee, K, Anderson, KJ, Anderson, S, Arcelli, S, Asai, S, Axen, D, Azuelos, G, Ball, AH, Barberio, E, Barlow, RJ, Bartoldus, R, Batley, JR, Beaudoin, G, Bechtluft, J, Beck, A, Beck, GA, Beeston, C, Behnke, T, Bell, KW, Bella, G, Bentvelsen, S, Berlich, P, Bethke, S, Biebel, O, Bloodworth, IJ, Bock, P, Bosch, HM, Boutemeur, M, Braibant, S, Bright-Thomas, P, Brown, RM, Buijs, A, Burckhart, HJ, Burgard, C, Bürgin, R, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlesworth, C, Charlton, DG, Chu, SL, Clarke, PEL, Clayton, JC, Clowes, SG, Cohen, I, Conboy, JE, Cooke, OC, Cuffiani, M, Dado, S, Dallapiccola, C, Dallavalle, GM, Darling, C, De Jong, S, Del Pozo, LA, Deng, H, Dixit, MS, Do Couto E Silva, E, Duboscq, JE, Duchovni, E, Duckeck, G, Duerdoth, IP, Dunwoody, UC, Edwards, JEG, Estabrooks, PG, Evans, HG, Fabbri, F, Fabbro, B, Fanti, M, Fath, P, Fiedler, F, Fierro, M, Fincke-Keeler, M, Fischer, HM, Folman, R, Fong, DG, Foucher, M, Fukui, H, Fürtjes, A, Gagnon, P, Gaidot, A, Gary, JW, Gascon, J, Gascon-Shotkin, SM, Geddes, NI, Geich-Gimbel, C, Gensler, SW, Gentit, FX, Geralis, T, Giacomelli, G, Giacomelli, P, Giacomelli, R, Gibson, V, Gibson, WR, Gillies, JD, Gingrich, DM, Goldberg, J, Goodrick, MJ, Gorn, W, Grandi, C, Gross, E, Hanson, GG, Hansroul, M, Hapke, M, Hargrove, CK, Hart, PA, Hartmann, C, Hauschild, M, Hawkes, CM, Hawkings, R, Hemingway, RJ, Herten, G, Heuer, RD, Hill, JC, Hillier, SJ, Hilse, T, Hobson, PR, Hochman, D, Homer, RJ, Honma, AK, Howard, R, Hughes-Jones, RE, Hutchcroft, DE, Igo-Kemenes, P, Imrie, DC, Jawahery, A, Jeffreys, PW, Jeremie, H, Jimack, M, Joly, A, Jones, M, Jones, RWL, Jovanovic, P, Kanzaki, J, Karlen, D, Kawagoe, K, Kawamoto, T, Keeler, RK, Kellogg, RG, Kennedy, BW, King, BJ, King, J, Kirk, J, Kluth, S, Kobayashi, T, Kobel, M, Koetke, DS, Kokott, TP, Komamiya, S, Kowalewski, R, Kress, T, Krieger, P, Von Krogh, J, Kyberd, P, Lafferty, GD, Lafoux, H, Lahmann, R, Lai, WP, Lanske, D, Lauber, J, Layter, JG, Lee, AM, Lefebvre, E, Lellouch, D, Letts, J, Levinson, L, Lloyd, SL, Loebinger, FK, Long, GD, Lorazo, B, Losty, MJ, Ludwig, J, Luig, A, Malik, A, Mannelli, M, Marcellini, S, Markus, C, Martin, AJ, Martin, JP, Mashimo, T, Matthews, W, Mättig, P, McKenna, J, Mckigney, EA, McMahon, TJ, McNab, AI, Meijers, F, Menke, S, Merritt, FS, Mes, H, Michelini, A, Mikenberg, G, Miller, DJ, Mir, R, Mohr, W, Montanari, A, Mori, T, Morii, M, Müller, U, Nellen, B, Nijjhar, B, O'Neale, SW, Oakham, FG, Odorici, F, Ogren, HO, Oldershaw, NJ, Oram, CJ, Oreglia, MJ, Orito, S, Palmonari, F, Pansart, JP, Patrick, GN, Pearce, MJ, Phillips, PD, Pilcher, JE, Pinfold, J, Plane, DE, Poffenberger, P, Poli, B, Posthaus, A, Pritchard, TW, Przysiezniak, H, Redmond, MW, Rees, DL, Rigby, D, Rison, MG, Robins, SA, Rodning, N, Roney, JM, Ros, E, Rossi, AM, Rosvick, M, Routenburg, P, Rozen, Y, Runge, K, Runolfsson, O, Rust, DR, Sasaki, M, Sbarra, C, Schaile, AD, Schaile, O, Scharf, F, Scharff-Hansen, P, Schenk, P, Schmitt, B, Schröder, M, Schultz-Coulon, HC, Schulz, M, Schütz, P, Schwiening, J, Scott, WG, Settles, M, Shears, TG, Shen, BC, Shepherd-Themistocleous, CH, Sherwood, P, Siroli, GP, Skillman, A, Skuja, A, Smith, AM, Smith, TJ, Snow, GA, Sobie, R, Söldner-Rembold, S, Springer, RW, Sproston, M, Stahl, A, Starks, M, Stegmann, C, Stephens, K, Steuerer, J, Stockhausen, B, Strom, D, Szymanski, P, Tafirout, R, Taras, P, Tarem, S, Tecchio, M, Teixeira-Dias, P, Tesch, N, Thomson, MA, Von Törne, E, Towers, S, Tscheulin, M, Tsukamoto, T, Turcot, AS, Turner-Watson, MF, Utzat, P, Van Kooten, R, Vasseur, G, Vikas, P, Vincter, M, Wäckerle, F, Wagner, A, Wagner, DL, Ward, CP, Ward, DR, Ward, JJ, Watkins, PM, Watson, AT, Watson, NK, Weber, P, Wells, PS, Wermes, N, Wilkens, B, Wilson, GW, Wilson, JA, Wlodek, T, Wolf, G, Wotton, S, Wyatt, TR, Yekutieli, G, Zacek, V, Zeuner, W & Zorn, GT 1996, 'Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X)', Zeitschrift fur Physik C-Particles and Fields, vol. 69, no. 2, pp. 195-214.
Akers, R. ; Alexander, G. ; Allison, J. ; Altekamp, N. ; Ametewee, K. ; Anderson, K. J. ; Anderson, S. ; Arcelli, S. ; Asai, S. ; Axen, D. ; Azuelos, G. ; Ball, A. H. ; Barberio, E. ; Barlow, R. J. ; Bartoldus, R. ; Batley, J. R. ; Beaudoin, G. ; Bechtluft, J. ; Beck, A. ; Beck, G. A. ; Beeston, C. ; Behnke, T. ; Bell, K. W. ; Bella, G. ; Bentvelsen, S. ; Berlich, P. ; Bethke, S. ; Biebel, O. ; Bloodworth, I. J. ; Bock, P. ; Bosch, H. M. ; Boutemeur, M. ; Braibant, S. ; Bright-Thomas, P. ; Brown, R. M. ; Buijs, A. ; Burckhart, H. J. ; Burgard, C. ; Bürgin, R. ; Capiluppi, P. ; Carnegie, R. K. ; Carter, A. A. ; Carter, J. R. ; Chang, C. Y. ; Charlesworth, C. ; Charlton, D. G. ; Chu, S. L. ; Clarke, P. E.L. ; Clayton, J. C. ; Clowes, S. G. ; Cohen, I. ; Conboy, J. E. ; Cooke, O. C. ; Cuffiani, M. ; Dado, S. ; Dallapiccola, C. ; Dallavalle, G. M. ; Darling, C. ; De Jong, S. ; Del Pozo, L. A. ; Deng, H. ; Dixit, M. S. ; Do Couto E Silva, E. ; Duboscq, J. E. ; Duchovni, E. ; Duckeck, G. ; Duerdoth, I. P. ; Dunwoody, U. C. ; Edwards, J. E.G. ; Estabrooks, P. G. ; Evans, H. G. ; Fabbri, F. ; Fabbro, B. ; Fanti, M. ; Fath, P. ; Fiedler, F. ; Fierro, M. ; Fincke-Keeler, M. ; Fischer, H. M. ; Folman, R. ; Fong, D. G. ; Foucher, M. ; Fukui, H. ; Fürtjes, A. ; Gagnon, P. ; Gaidot, A. ; Gary, J. W. ; Gascon, J. ; Gascon-Shotkin, S. M. ; Geddes, N. I. ; Geich-Gimbel, C. ; Gensler, S. W. ; Gentit, F. X. ; Geralis, T. ; Giacomelli, G. ; Giacomelli, P. ; Giacomelli, R. ; Gibson, V. ; Gibson, W. R. ; Gillies, J. D. ; Gingrich, D. M. ; Goldberg, J. ; Goodrick, M. J. ; Gorn, W. ; Grandi, C. ; Gross, E. ; Hanson, G. G. ; Hansroul, M. ; Hapke, M. ; Hargrove, C. K. ; Hart, P. A. ; Hartmann, C. ; Hauschild, M. ; Hawkes, C. M. ; Hawkings, R. ; Hemingway, R. J. ; Herten, G. ; Heuer, R. D. ; Hill, J. C. ; Hillier, S. J. ; Hilse, T. ; Hobson, P. R. ; Hochman, D. ; Homer, R. J. ; Honma, A. K. ; Howard, R. ; Hughes-Jones, R. E. ; Hutchcroft, D. E. ; Igo-Kemenes, P. ; Imrie, D. C. ; Jawahery, A. ; Jeffreys, P. W. ; Jeremie, H. ; Jimack, M. ; Joly, A. ; Jones, M. ; Jones, R. W.L. ; Jovanovic, P. ; Kanzaki, J. ; Karlen, D. ; Kawagoe, K. ; Kawamoto, T. ; Keeler, R. K. ; Kellogg, R. G. ; Kennedy, B. W. ; King, B. J. ; King, J. ; Kirk, J. ; Kluth, S. ; Kobayashi, T. ; Kobel, M. ; Koetke, D. S. ; Kokott, T. P. ; Komamiya, Sachio ; Kowalewski, R. ; Kress, T. ; Krieger, P. ; Von Krogh, J. ; Kyberd, P. ; Lafferty, G. D. ; Lafoux, H. ; Lahmann, R. ; Lai, W. P. ; Lanske, D. ; Lauber, J. ; Layter, J. G. ; Lee, A. M. ; Lefebvre, E. ; Lellouch, D. ; Letts, J. ; Levinson, L. ; Lloyd, S. L. ; Loebinger, F. K. ; Long, G. D. ; Lorazo, B. ; Losty, M. J. ; Ludwig, J. ; Luig, A. ; Malik, A. ; Mannelli, M. ; Marcellini, S. ; Markus, C. ; Martin, A. J. ; Martin, J. P. ; Mashimo, T. ; Matthews, W. ; Mättig, P. ; McKenna, J. ; Mckigney, E. A. ; McMahon, T. J. ; McNab, A. I. ; Meijers, F. ; Menke, S. ; Merritt, F. S. ; Mes, H. ; Michelini, A. ; Mikenberg, G. ; Miller, D. J. ; Mir, R. ; Mohr, W. ; Montanari, A. ; Mori, T. ; Morii, M. ; Müller, U. ; Nellen, B. ; Nijjhar, B. ; O'Neale, S. W. ; Oakham, F. G. ; Odorici, F. ; Ogren, H. O. ; Oldershaw, N. J. ; Oram, C. J. ; Oreglia, M. J. ; Orito, S. ; Palmonari, F. ; Pansart, J. P. ; Patrick, G. N. ; Pearce, M. J. ; Phillips, P. D. ; Pilcher, J. E. ; Pinfold, J. ; Plane, D. E. ; Poffenberger, P. ; Poli, B. ; Posthaus, A. ; Pritchard, T. W. ; Przysiezniak, H. ; Redmond, M. W. ; Rees, D. L. ; Rigby, D. ; Rison, M. G. ; Robins, S. A. ; Rodning, N. ; Roney, J. M. ; Ros, E. ; Rossi, A. M. ; Rosvick, M. ; Routenburg, P. ; Rozen, Y. ; Runge, K. ; Runolfsson, O. ; Rust, D. R. ; Sasaki, M. ; Sbarra, C. ; Schaile, A. D. ; Schaile, O. ; Scharf, F. ; Scharff-Hansen, P. ; Schenk, P. ; Schmitt, B. ; Schröder, M. ; Schultz-Coulon, H. C. ; Schulz, M. ; Schütz, P. ; Schwiening, J. ; Scott, W. G. ; Settles, M. ; Shears, T. G. ; Shen, B. C. ; Shepherd-Themistocleous, C. H. ; Sherwood, P. ; Siroli, G. P. ; Skillman, A. ; Skuja, A. ; Smith, A. M. ; Smith, T. J. ; Snow, G. A. ; Sobie, R. ; Söldner-Rembold, S. ; Springer, R. W. ; Sproston, M. ; Stahl, A. ; Starks, M. ; Stegmann, C. ; Stephens, K. ; Steuerer, J. ; Stockhausen, B. ; Strom, D. ; Szymanski, P. ; Tafirout, R. ; Taras, P. ; Tarem, S. ; Tecchio, M. ; Teixeira-Dias, P. ; Tesch, N. ; Thomson, M. A. ; Von Törne, E. ; Towers, S. ; Tscheulin, M. ; Tsukamoto, T. ; Turcot, A. S. ; Turner-Watson, M. F. ; Utzat, P. ; Van Kooten, R. ; Vasseur, G. ; Vikas, P. ; Vincter, M. ; Wäckerle, F. ; Wagner, A. ; Wagner, D. L. ; Ward, C. P. ; Ward, D. R. ; Ward, J. J. ; Watkins, P. M. ; Watson, A. T. ; Watson, N. K. ; Weber, P. ; Wells, P. S. ; Wermes, N. ; Wilkens, B. ; Wilson, G. W. ; Wilson, J. A. ; Wlodek, T. ; Wolf, G. ; Wotton, S. ; Wyatt, T. R. ; Yekutieli, G. ; Zacek, V. ; Zeuner, W. ; Zorn, G. T. / Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X). In: Zeitschrift fur Physik C-Particles and Fields. 1996 ; Vol. 69, No. 2. pp. 195-214.
@article{232bd75c77294a39957d70529b4cb410,
title = "Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X)",
abstract = "The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990 and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce a Λ baryon are identified through the correlation of the baryon number of the Λ and the electric charge of the lepton. To measure the lifetime, the decay point of the b baryon is estimated by the Λ-lepton vertex, and the observed distribution of decay lengths is fitted simultaneously in 874 right-sign and 384 wrong-sign combinations. In a separate method, the impact parameter distribution of the leptons is fitted in a subset of these data. When the two results are combined, taking correlations into account, the average b-baryon lifetime is found to be τ = 1.16 ± 0.11 (stat.) ± 0.06 (syst.) ps. Using the same data, the product branching ratio is measured to be f(b → Δb)·BR(Λb → Λℓ-ν̄X) = (2.91 ± 0.23 (stat.) ±0.25 (syst.))·10-3, where the symbol f(b → Λb) is the fraction of b quarks from Z0 decays forming b baryons, Λb represents all b-flavoured baryons and ℓ is either an electron or a muon.",
author = "R. Akers and G. Alexander and J. Allison and N. Altekamp and K. Ametewee and Anderson, {K. J.} and S. Anderson and S. Arcelli and S. Asai and D. Axen and G. Azuelos and Ball, {A. H.} and E. Barberio and Barlow, {R. J.} and R. Bartoldus and Batley, {J. R.} and G. Beaudoin and J. Bechtluft and A. Beck and Beck, {G. A.} and C. Beeston and T. Behnke and Bell, {K. W.} and G. Bella and S. Bentvelsen and P. Berlich and S. Bethke and O. Biebel and Bloodworth, {I. J.} and P. Bock and Bosch, {H. M.} and M. Boutemeur and S. Braibant and P. Bright-Thomas and Brown, {R. M.} and A. Buijs and Burckhart, {H. J.} and C. Burgard and R. B{\"u}rgin and P. Capiluppi and Carnegie, {R. K.} and Carter, {A. A.} and Carter, {J. R.} and Chang, {C. Y.} and C. Charlesworth and Charlton, {D. G.} and Chu, {S. L.} and Clarke, {P. E.L.} and Clayton, {J. C.} and Clowes, {S. G.} and I. Cohen and Conboy, {J. E.} and Cooke, {O. C.} and M. Cuffiani and S. Dado and C. Dallapiccola and Dallavalle, {G. M.} and C. Darling and {De Jong}, S. and {Del Pozo}, {L. A.} and H. Deng and Dixit, {M. S.} and {Do Couto E Silva}, E. and Duboscq, {J. E.} and E. Duchovni and G. Duckeck and Duerdoth, {I. P.} and Dunwoody, {U. C.} and Edwards, {J. E.G.} and Estabrooks, {P. G.} and Evans, {H. G.} and F. Fabbri and B. Fabbro and M. Fanti and P. Fath and F. Fiedler and M. Fierro and M. Fincke-Keeler and Fischer, {H. M.} and R. Folman and Fong, {D. G.} and M. Foucher and H. Fukui and A. F{\"u}rtjes and P. Gagnon and A. Gaidot and Gary, {J. W.} and J. Gascon and Gascon-Shotkin, {S. M.} and Geddes, {N. I.} and C. Geich-Gimbel and Gensler, {S. W.} and Gentit, {F. X.} and T. Geralis and G. Giacomelli and P. Giacomelli and R. Giacomelli and V. Gibson and Gibson, {W. R.} and Gillies, {J. D.} and Gingrich, {D. M.} and J. Goldberg and Goodrick, {M. J.} and W. Gorn and C. Grandi and E. Gross and Hanson, {G. G.} and M. Hansroul and M. Hapke and Hargrove, {C. K.} and Hart, {P. A.} and C. Hartmann and M. Hauschild and Hawkes, {C. M.} and R. Hawkings and Hemingway, {R. J.} and G. Herten and Heuer, {R. D.} and Hill, {J. C.} and Hillier, {S. J.} and T. Hilse and Hobson, {P. R.} and D. Hochman and Homer, {R. J.} and Honma, {A. K.} and R. Howard and Hughes-Jones, {R. E.} and Hutchcroft, {D. E.} and P. Igo-Kemenes and Imrie, {D. C.} and A. Jawahery and Jeffreys, {P. W.} and H. Jeremie and M. Jimack and A. Joly and M. Jones and Jones, {R. W.L.} and P. Jovanovic and J. Kanzaki and D. Karlen and K. Kawagoe and T. Kawamoto and Keeler, {R. K.} and Kellogg, {R. G.} and Kennedy, {B. W.} and King, {B. J.} and J. King and J. Kirk and S. Kluth and T. Kobayashi and M. Kobel and Koetke, {D. S.} and Kokott, {T. P.} and Sachio Komamiya and R. Kowalewski and T. Kress and P. Krieger and {Von Krogh}, J. and P. Kyberd and Lafferty, {G. D.} and H. Lafoux and R. Lahmann and Lai, {W. P.} and D. Lanske and J. Lauber and Layter, {J. G.} and Lee, {A. M.} and E. Lefebvre and D. Lellouch and J. Letts and L. Levinson and Lloyd, {S. L.} and Loebinger, {F. K.} and Long, {G. D.} and B. Lorazo and Losty, {M. J.} and J. Ludwig and A. Luig and A. Malik and M. Mannelli and S. Marcellini and C. Markus and Martin, {A. J.} and Martin, {J. P.} and T. Mashimo and W. Matthews and P. M{\"a}ttig and J. McKenna and Mckigney, {E. A.} and McMahon, {T. J.} and McNab, {A. I.} and F. Meijers and S. Menke and Merritt, {F. S.} and H. Mes and A. Michelini and G. Mikenberg and Miller, {D. J.} and R. Mir and W. Mohr and A. Montanari and T. Mori and M. Morii and U. M{\"u}ller and B. Nellen and B. Nijjhar and O'Neale, {S. W.} and Oakham, {F. G.} and F. Odorici and Ogren, {H. O.} and Oldershaw, {N. J.} and Oram, {C. J.} and Oreglia, {M. J.} and S. Orito and F. Palmonari and Pansart, {J. P.} and Patrick, {G. N.} and Pearce, {M. J.} and Phillips, {P. D.} and Pilcher, {J. E.} and J. Pinfold and Plane, {D. E.} and P. Poffenberger and B. Poli and A. Posthaus and Pritchard, {T. W.} and H. Przysiezniak and Redmond, {M. W.} and Rees, {D. L.} and D. Rigby and Rison, {M. G.} and Robins, {S. A.} and N. Rodning and Roney, {J. M.} and E. Ros and Rossi, {A. M.} and M. Rosvick and P. Routenburg and Y. Rozen and K. Runge and O. Runolfsson and Rust, {D. R.} and M. Sasaki and C. Sbarra and Schaile, {A. D.} and O. Schaile and F. Scharf and P. Scharff-Hansen and P. Schenk and B. Schmitt and M. Schr{\"o}der and Schultz-Coulon, {H. C.} and M. Schulz and P. Sch{\"u}tz and J. Schwiening and Scott, {W. G.} and M. Settles and Shears, {T. G.} and Shen, {B. C.} and Shepherd-Themistocleous, {C. H.} and P. Sherwood and Siroli, {G. P.} and A. Skillman and A. Skuja and Smith, {A. M.} and Smith, {T. J.} and Snow, {G. A.} and R. Sobie and S. S{\"o}ldner-Rembold and Springer, {R. W.} and M. Sproston and A. Stahl and M. Starks and C. Stegmann and K. Stephens and J. Steuerer and B. Stockhausen and D. Strom and P. Szymanski and R. Tafirout and P. Taras and S. Tarem and M. Tecchio and P. Teixeira-Dias and N. Tesch and Thomson, {M. A.} and {Von T{\"o}rne}, E. and S. Towers and M. Tscheulin and T. Tsukamoto and Turcot, {A. S.} and Turner-Watson, {M. F.} and P. Utzat and {Van Kooten}, R. and G. Vasseur and P. Vikas and M. Vincter and F. W{\"a}ckerle and A. Wagner and Wagner, {D. L.} and Ward, {C. P.} and Ward, {D. R.} and Ward, {J. J.} and Watkins, {P. M.} and Watson, {A. T.} and Watson, {N. K.} and P. Weber and Wells, {P. S.} and N. Wermes and B. Wilkens and Wilson, {G. W.} and Wilson, {J. A.} and T. Wlodek and G. Wolf and S. Wotton and Wyatt, {T. R.} and G. Yekutieli and V. Zacek and W. Zeuner and Zorn, {G. T.}",
year = "1996",
month = "1",
day = "1",
language = "English",
volume = "69",
pages = "195--214",
journal = "European Physical Journal C",
issn = "1434-6044",
publisher = "Springer New York",
number = "2",

}

TY - JOUR

T1 - Measurement of the average b-baryon lifetime and the product branching ratio f(b → Λb) · BR(Λb → Λℓ-ν̄X)

AU - Akers, R.

AU - Alexander, G.

AU - Allison, J.

AU - Altekamp, N.

AU - Ametewee, K.

AU - Anderson, K. J.

AU - Anderson, S.

AU - Arcelli, S.

AU - Asai, S.

AU - Axen, D.

AU - Azuelos, G.

AU - Ball, A. H.

AU - Barberio, E.

AU - Barlow, R. J.

AU - Bartoldus, R.

AU - Batley, J. R.

AU - Beaudoin, G.

AU - Bechtluft, J.

AU - Beck, A.

AU - Beck, G. A.

AU - Beeston, C.

AU - Behnke, T.

AU - Bell, K. W.

AU - Bella, G.

AU - Bentvelsen, S.

AU - Berlich, P.

AU - Bethke, S.

AU - Biebel, O.

AU - Bloodworth, I. J.

AU - Bock, P.

AU - Bosch, H. M.

AU - Boutemeur, M.

AU - Braibant, S.

AU - Bright-Thomas, P.

AU - Brown, R. M.

AU - Buijs, A.

AU - Burckhart, H. J.

AU - Burgard, C.

AU - Bürgin, R.

AU - Capiluppi, P.

AU - Carnegie, R. K.

AU - Carter, A. A.

AU - Carter, J. R.

AU - Chang, C. Y.

AU - Charlesworth, C.

AU - Charlton, D. G.

AU - Chu, S. L.

AU - Clarke, P. E.L.

AU - Clayton, J. C.

AU - Clowes, S. G.

AU - Cohen, I.

AU - Conboy, J. E.

AU - Cooke, O. C.

AU - Cuffiani, M.

AU - Dado, S.

AU - Dallapiccola, C.

AU - Dallavalle, G. M.

AU - Darling, C.

AU - De Jong, S.

AU - Del Pozo, L. A.

AU - Deng, H.

AU - Dixit, M. S.

AU - Do Couto E Silva, E.

AU - Duboscq, J. E.

AU - Duchovni, E.

AU - Duckeck, G.

AU - Duerdoth, I. P.

AU - Dunwoody, U. C.

AU - Edwards, J. E.G.

AU - Estabrooks, P. G.

AU - Evans, H. G.

AU - Fabbri, F.

AU - Fabbro, B.

AU - Fanti, M.

AU - Fath, P.

AU - Fiedler, F.

AU - Fierro, M.

AU - Fincke-Keeler, M.

AU - Fischer, H. M.

AU - Folman, R.

AU - Fong, D. G.

AU - Foucher, M.

AU - Fukui, H.

AU - Fürtjes, A.

AU - Gagnon, P.

AU - Gaidot, A.

AU - Gary, J. W.

AU - Gascon, J.

AU - Gascon-Shotkin, S. M.

AU - Geddes, N. I.

AU - Geich-Gimbel, C.

AU - Gensler, S. W.

AU - Gentit, F. X.

AU - Geralis, T.

AU - Giacomelli, G.

AU - Giacomelli, P.

AU - Giacomelli, R.

AU - Gibson, V.

AU - Gibson, W. R.

AU - Gillies, J. D.

AU - Gingrich, D. M.

AU - Goldberg, J.

AU - Goodrick, M. J.

AU - Gorn, W.

AU - Grandi, C.

AU - Gross, E.

AU - Hanson, G. G.

AU - Hansroul, M.

AU - Hapke, M.

AU - Hargrove, C. K.

AU - Hart, P. A.

AU - Hartmann, C.

AU - Hauschild, M.

AU - Hawkes, C. M.

AU - Hawkings, R.

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PY - 1996/1/1

Y1 - 1996/1/1

N2 - The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990 and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce a Λ baryon are identified through the correlation of the baryon number of the Λ and the electric charge of the lepton. To measure the lifetime, the decay point of the b baryon is estimated by the Λ-lepton vertex, and the observed distribution of decay lengths is fitted simultaneously in 874 right-sign and 384 wrong-sign combinations. In a separate method, the impact parameter distribution of the leptons is fitted in a subset of these data. When the two results are combined, taking correlations into account, the average b-baryon lifetime is found to be τ = 1.16 ± 0.11 (stat.) ± 0.06 (syst.) ps. Using the same data, the product branching ratio is measured to be f(b → Δb)·BR(Λb → Λℓ-ν̄X) = (2.91 ± 0.23 (stat.) ±0.25 (syst.))·10-3, where the symbol f(b → Λb) is the fraction of b quarks from Z0 decays forming b baryons, Λb represents all b-flavoured baryons and ℓ is either an electron or a muon.

AB - The average lifetime of b-flavoured baryons measured with the OPAL detector is updated to include data collected between 1990 and 1994 at LEP. Bottom-flavoured baryons that decay semileptonically and produce a Λ baryon are identified through the correlation of the baryon number of the Λ and the electric charge of the lepton. To measure the lifetime, the decay point of the b baryon is estimated by the Λ-lepton vertex, and the observed distribution of decay lengths is fitted simultaneously in 874 right-sign and 384 wrong-sign combinations. In a separate method, the impact parameter distribution of the leptons is fitted in a subset of these data. When the two results are combined, taking correlations into account, the average b-baryon lifetime is found to be τ = 1.16 ± 0.11 (stat.) ± 0.06 (syst.) ps. Using the same data, the product branching ratio is measured to be f(b → Δb)·BR(Λb → Λℓ-ν̄X) = (2.91 ± 0.23 (stat.) ±0.25 (syst.))·10-3, where the symbol f(b → Λb) is the fraction of b quarks from Z0 decays forming b baryons, Λb represents all b-flavoured baryons and ℓ is either an electron or a muon.

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M3 - Article

AN - SCOPUS:0001351115

VL - 69

SP - 195

EP - 214

JO - European Physical Journal C

JF - European Physical Journal C

SN - 1434-6044

IS - 2

ER -