Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP

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, S. Bethke, A. Beck, G. A. Beck & 299 others C. Beeston, T. Behnke, K. W. Bell, G. Bella, S. Bentvelsen, P. Berlich, J. Bechtluft, 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, R. Bürgin, C. Burgard, 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. Ducrdoth, 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, 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, J. Goldberg, D. M. Gingrich, 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, D. Karlen, J. Kanzaki, Kiyotomo 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, S. 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, P. Schütz, M. Schulz, 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

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Abstract

The fragmentation function for the process e+e-→h+X, where h represents a hadron, may be decomposed into transverse, longitudinal and asymmetric contributions by analysis of the distribution of polar production angles. A number of new tests of QCD have been proposed using these fragmentation functions, but so far no data have been published on the separate components. We have performed such a separation using data on charged particles from hadronic Z0 decays at Opal, and have compared the results with the predictions of QCD. By integrating the fragmentation functions, we determine the average charged particle multiplicity to be {Mathematical expression}. The longitudinal to total cross-section ratio is determined to be σLtot=0.057±0.005. From the longitudinal fragmentation function we are able to extract the gluon fragmentation function. The connection between the asymmetry fragmentation function and electroweak asymmetrics is discussed.

Original languageEnglish
Pages (from-to)203-213
Number of pages11
JournalZeitschrift für Physik C Particles and Fields
Volume68
Issue number2
DOIs
Publication statusPublished - Jun 1 1995

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fragmentation
asymmetry
Charged particles
charged particles
quantum chromodynamics
cross sections
decay
predictions

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Akers, R., Alexander, G., Allison, J., Altekamp, N., Ametewee, K., Anderson, K. J., ... Zorn, G. T. (1995). Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP. Zeitschrift für Physik C Particles and Fields, 68(2), 203-213. https://doi.org/10.1007/BF01566668

Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP. / 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.; Bethke, S.; Beck, A.; Beck, G. A.; Beeston, C.; Behnke, T.; Bell, K. W.; Bella, G.; Bentvelsen, S.; Berlich, P.; Bechtluft, J.; 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.; Bürgin, R.; Burgard, C.; 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.; Ducrdoth, 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.; 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.; Goldberg, J.; Gingrich, D. M.; 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.; Karlen, D.; Kanzaki, J.; Kawagoe, Kiyotomo; 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, S.; 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.; Schütz, P.; Schulz, M.; 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 für Physik C Particles and Fields, Vol. 68, No. 2, 01.06.1995, p. 203-213.

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, Bethke, S, Beck, A, Beck, GA, Beeston, C, Behnke, T, Bell, KW, Bella, G, Bentvelsen, S, Berlich, P, Bechtluft, J, Biebel, O, Bloodworth, IJ, Bock, P, Bosch, HM, Boutemeur, M, Braibant, S, Bright-Thomas, P, Brown, RM, Buijs, A, Burckhart, HJ, Bürgin, R, Burgard, C, 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, Ducrdoth, 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, Geddes, NI, Geich-Gimbel, C, Gensler, SW, Gentit, FX, Geralis, T, Giacomelli, G, Giacomelli, P, Giacomelli, R, Gibson, V, Gibson, WR, Gillies, JD, Goldberg, J, Gingrich, DM, 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, Karlen, D, Kanzaki, J, 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, Schütz, P, Schulz, M, 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 1995, 'Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP', Zeitschrift für Physik C Particles and Fields, vol. 68, no. 2, pp. 203-213. https://doi.org/10.1007/BF01566668
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. ; Bethke, S. ; Beck, A. ; Beck, G. A. ; Beeston, C. ; Behnke, T. ; Bell, K. W. ; Bella, G. ; Bentvelsen, S. ; Berlich, P. ; Bechtluft, J. ; 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. ; Bürgin, R. ; Burgard, C. ; 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. ; Ducrdoth, 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. ; 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. ; Goldberg, J. ; Gingrich, D. M. ; 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. ; Karlen, D. ; Kanzaki, J. ; Kawagoe, Kiyotomo ; 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, S. ; 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. ; Schütz, P. ; Schulz, M. ; 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 longitudinal, transverse and asymmetry fragmentation functions at LEP. In: Zeitschrift für Physik C Particles and Fields. 1995 ; Vol. 68, No. 2. pp. 203-213.
@article{2c3d9445143c446ebb9ad6a6792dd181,
title = "Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP",
abstract = "The fragmentation function for the process e+e-→h+X, where h represents a hadron, may be decomposed into transverse, longitudinal and asymmetric contributions by analysis of the distribution of polar production angles. A number of new tests of QCD have been proposed using these fragmentation functions, but so far no data have been published on the separate components. We have performed such a separation using data on charged particles from hadronic Z0 decays at Opal, and have compared the results with the predictions of QCD. By integrating the fragmentation functions, we determine the average charged particle multiplicity to be {Mathematical expression}. The longitudinal to total cross-section ratio is determined to be σL/σtot=0.057±0.005. From the longitudinal fragmentation function we are able to extract the gluon fragmentation function. The connection between the asymmetry fragmentation function and electroweak asymmetrics is discussed.",
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 S. Bethke 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 J. Bechtluft 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 R. B{\"u}rgin and C. Burgard 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 Ducrdoth, {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 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 J. Goldberg and Gingrich, {D. M.} 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 D. Karlen and J. Kanzaki and Kiyotomo 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 S. 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 P. Sch{\"u}tz and M. Schulz 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 = "1995",
month = "6",
day = "1",
doi = "10.1007/BF01566668",
language = "English",
volume = "68",
pages = "203--213",
journal = "European Physical Journal C",
issn = "1434-6044",
publisher = "Springer New York",
number = "2",

}

TY - JOUR

T1 - Measurement of the longitudinal, transverse and asymmetry fragmentation functions at LEP

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 - Bethke, S.

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 - Bechtluft, J.

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 - Bürgin, R.

AU - Burgard, C.

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 - Ducrdoth, 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 - 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 - Goldberg, J.

AU - Gingrich, D. M.

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.

AU - Hemingway, R. J.

AU - Herten, G.

AU - Heuer, R. D.

AU - Hill, J. C.

AU - Hillier, S. J.

AU - Hilse, T.

AU - Hobson, P. R.

AU - Hochman, D.

AU - Homer, R. J.

AU - Honma, A. K.

AU - Howard, R.

AU - Hughes-Jones, R. E.

AU - Hutchcroft, D. E.

AU - Igo-Kemenes, P.

AU - Imrie, D. C.

AU - Jawahery, A.

AU - Jeffreys, P. W.

AU - Jeremie, H.

AU - Jimack, M.

AU - Joly, A.

AU - Jones, M.

AU - Jones, R. W.L.

AU - Jovanovic, P.

AU - Karlen, D.

AU - Kanzaki, J.

AU - Kawagoe, Kiyotomo

AU - Kawamoto, T.

AU - Keeler, R. K.

AU - Kellogg, R. G.

AU - Kennedy, B. W.

AU - King, B. J.

AU - King, J.

AU - Kirk, J.

AU - Kluth, S.

AU - Kobayashi, T.

AU - Kobel, M.

AU - Koetke, D. S.

AU - Kokott, T. P.

AU - Komamiya, S.

AU - Kowalewski, R.

AU - Kress, T.

AU - Krieger, P.

AU - von Krogh, J.

AU - Kyberd, P.

AU - Lafferty, G. D.

AU - Lafoux, H.

AU - Lahmann, R.

AU - Lai, W. P.

AU - Lanske, D.

AU - Lauber, J.

AU - Layter, J. G.

AU - Lee, A. M.

AU - Lefebvre, E.

AU - Lellouch, D.

AU - Letts, J.

AU - Levinson, L.

AU - Lloyd, S. L.

AU - Loebinger, F. K.

AU - Long, G. D.

AU - Lorazo, B.

AU - Losty, M. J.

AU - Ludwig, J.

AU - Luig, A.

AU - Malik, A.

AU - Mannelli, M.

AU - Marcellini, S.

AU - Markus, C.

AU - Martin, A. J.

AU - Martin, J. P.

AU - Mashimo, T.

AU - Matthews, W.

AU - Mättig, P.

AU - McKenna, J.

AU - Mckigney, E. A.

AU - McMahon, T. J.

AU - McNab, A. I.

AU - Meijers, F.

AU - Menke, S.

AU - Merritt, F. S.

AU - Mes, H.

AU - Michelini, A.

AU - Mikenberg, G.

AU - Miller, D. J.

AU - Mir, R.

AU - Mohr, W.

AU - Montanari, A.

AU - Mori, T.

AU - Morii, M.

AU - Müller, U.

AU - Nellen, B.

AU - Nijjhar, B.

AU - O'Neale, S. W.

AU - Oakham, F. G.

AU - Odorici, F.

AU - Ogren, H. O.

AU - Oldershaw, N. J.

AU - Oram, C. J.

AU - Oreglia, M. J.

AU - Orito, S.

AU - Palmonari, F.

AU - Pansart, J. P.

AU - Patrick, G. N.

AU - Pearce, M. J.

AU - Phillips, P. D.

AU - Pilcher, J. E.

AU - Pinfold, J.

AU - Plane, D. E.

AU - Poffenberger, P.

AU - Poli, B.

AU - Posthaus, A.

AU - Pritchard, T. W.

AU - Przysiezniak, H.

AU - Redmond, M. W.

AU - Rees, D. L.

AU - Rigby, D.

AU - Rison, M. G.

AU - Robins, S. A.

AU - Rodning, N.

AU - Roney, J. M.

AU - Ros, E.

AU - Rossi, A. M.

AU - Rosvick, M.

AU - Routenburg, P.

AU - Rozen, Y.

AU - Runge, K.

AU - Runolfsson, O.

AU - Rust, D. R.

AU - Sasaki, M.

AU - Sbarra, C.

AU - Schaile, A. D.

AU - Schaile, O.

AU - Scharf, F.

AU - Scharff-Hansen, P.

AU - Schenk, P.

AU - Schmitt, B.

AU - Schröder, M.

AU - Schultz-Coulon, H. C.

AU - Schütz, P.

AU - Schulz, M.

AU - Schwiening, J.

AU - Scott, W. G.

AU - Settles, M.

AU - Shears, T. G.

AU - Shen, B. C.

AU - Shepherd-Themistocleous, C. H.

AU - Sherwood, P.

AU - Siroli, G. P.

AU - Skillman, A.

AU - Skuja, A.

AU - Smith, A. M.

AU - Smith, T. J.

AU - Snow, G. A.

AU - Sobie, R.

AU - Söldner-Rembold, S.

AU - Springer, R. W.

AU - Sproston, M.

AU - Stahl, A.

AU - Starks, M.

AU - Stegmann, C.

AU - Stephens, K.

AU - Steuerer, J.

AU - Stockhausen, B.

AU - Strom, D.

AU - Szymanski, P.

AU - Tafirout, R.

AU - Taras, P.

AU - Tarem, S.

AU - Tecchio, M.

AU - Teixeira-Dias, P.

AU - Tesch, N.

AU - Thomson, M. A.

AU - von Törne, E.

AU - Towers, S.

AU - Tscheulin, M.

AU - Tsukamoto, T.

AU - Turcot, A. S.

AU - Turner-Watson, M. F.

AU - Utzat, P.

AU - Van Kooten, R.

AU - Vasseur, G.

AU - Vikas, P.

AU - Vincter, M.

AU - Wäckerle, F.

AU - Wagner, A.

AU - Wagner, D. L.

AU - Ward, C. P.

AU - Ward, D. R.

AU - Ward, J. J.

AU - Watkins, P. M.

AU - Watson, A. T.

AU - Watson, N. K.

AU - Weber, P.

AU - Wells, P. S.

AU - Wermes, N.

AU - Wilkens, B.

AU - Wilson, G. W.

AU - Wilson, J. A.

AU - Wlodek, T.

AU - Wolf, G.

AU - Wotton, S.

AU - Wyatt, T. R.

AU - Yekutieli, G.

AU - Zacek, V.

AU - Zeuner, W.

AU - Zorn, G. T.

PY - 1995/6/1

Y1 - 1995/6/1

N2 - The fragmentation function for the process e+e-→h+X, where h represents a hadron, may be decomposed into transverse, longitudinal and asymmetric contributions by analysis of the distribution of polar production angles. A number of new tests of QCD have been proposed using these fragmentation functions, but so far no data have been published on the separate components. We have performed such a separation using data on charged particles from hadronic Z0 decays at Opal, and have compared the results with the predictions of QCD. By integrating the fragmentation functions, we determine the average charged particle multiplicity to be {Mathematical expression}. The longitudinal to total cross-section ratio is determined to be σL/σtot=0.057±0.005. From the longitudinal fragmentation function we are able to extract the gluon fragmentation function. The connection between the asymmetry fragmentation function and electroweak asymmetrics is discussed.

AB - The fragmentation function for the process e+e-→h+X, where h represents a hadron, may be decomposed into transverse, longitudinal and asymmetric contributions by analysis of the distribution of polar production angles. A number of new tests of QCD have been proposed using these fragmentation functions, but so far no data have been published on the separate components. We have performed such a separation using data on charged particles from hadronic Z0 decays at Opal, and have compared the results with the predictions of QCD. By integrating the fragmentation functions, we determine the average charged particle multiplicity to be {Mathematical expression}. The longitudinal to total cross-section ratio is determined to be σL/σtot=0.057±0.005. From the longitudinal fragmentation function we are able to extract the gluon fragmentation function. The connection between the asymmetry fragmentation function and electroweak asymmetrics is discussed.

UR - http://www.scopus.com/inward/record.url?scp=34249759950&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34249759950&partnerID=8YFLogxK

U2 - 10.1007/BF01566668

DO - 10.1007/BF01566668

M3 - Article

VL - 68

SP - 203

EP - 213

JO - European Physical Journal C

JF - European Physical Journal C

SN - 1434-6044

IS - 2

ER -