Advertisement

Journal of High Energy Physics

, 2015:67 | Cite as

Heavy baryons as polarimeters at colliders

  • Mario Galanti
  • Andrea Giammanco
  • Yuval Grossman
  • Yevgeny KatsEmail author
  • Emmanuel Stamou
  • Jure Zupan
Open Access
Regular Article - Theoretical Physics

Abstract

In new-physics processes that produce b or c jets, a measurement of the initial b or c-quark polarization could provide crucial information about the structure of the new physics. In the heavy-quark limit, the b and c-quark polarizations are preserved in the lightest baryons they hadronize into, Λ b and Λ c , respectively. We revisit the prediction for the polarization retention after the hadronization process and extend it to the case of transverse polarization. We show how ATLAS and CMS can measure the b-quark polarization using semileptonic Λ b decays, and the c-quark polarization using Λ c +  → pK π + decays. For calibrating both measurements we suggest to use \( t\overline{t} \) samples in which these polarizations can be measured with precision of order 10% using 100 fb−1 of data in Run 2 of the LHC. Measurements of the transverse polarization in QCD events at ATLAS, CMS and LHCb are motivated as well. The proposed measurements give access to nonperturbative QCD parameters relevant to the dynamics of the hadronization process.

Keywords

QCD Phenomenology Hadronic Colliders 

Notes

Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.

References

  1. [1]
    CMS collaboration, Measurement of top quark polarization in t-channel single-top production, CMS-PAS-TOP-13-001 (2013).
  2. [2]
    J.A. Aguilar-Saavedra and S. Amor dos Santos, New directions for top quark polarization in the t-channel process, Phys. Rev. D 89 (2014) 114009 [arXiv:1404.1585] [INSPIRE].ADSGoogle Scholar
  3. [3]
    R. Harnik, A. Martin, T. Okui, R. Primulando and F. Yu, Measuring CP-violation in h→τ+τ at colliders,Phys. Rev. D 88 (2013) 076009 [arXiv:1308.1094] [INSPIRE].ADSGoogle Scholar
  4. [4]
    M. Blanke, G.F. Giudice, P. Paradisi, G. Perez and J. Zupan, Flavoured naturalness, JHEP 06 (2013) 022 [arXiv:1302.7232] [INSPIRE].CrossRefADSGoogle Scholar
  5. [5]
    I. Galon, G. Perez and Y. Shadmi, Non-degenerate squarks from flavored gauge mediation, JHEP 09 (2013) 117 [arXiv:1306.6631] [INSPIRE].CrossRefADSGoogle Scholar
  6. [6]
    B. Keren-Zur et al., On partial compositeness and the CP asymmetry in charm decays, Nucl. Phys. B 867 (2013) 394 [arXiv:1205.5803] [INSPIRE].CrossRefADSGoogle Scholar
  7. [7]
    C. Delaunay et al., Light non-degenerate composite partners at the LHC, JHEP 02 (2014) 055 [arXiv:1311.2072] [INSPIRE].CrossRefADSGoogle Scholar
  8. [8]
    S. Fichet, B. Herrmann and Y. Stoll, Tasting the SU(5) nature of supersymmetry at the LHC, JHEP 05 (2015) 091 [arXiv:1501.05307] [INSPIRE].CrossRefADSGoogle Scholar
  9. [9]
    T. Mannel and G.A. Schuler, Semileptonic decays of bottom baryons at LEP, Phys. Lett. B 279 (1992) 194 [INSPIRE].CrossRefADSGoogle Scholar
  10. [10]
    A.H. Ball et al., Report of the b fragmentation working group, J. Phys. G 18 (1992) 1703 [INSPIRE].CrossRefADSGoogle Scholar
  11. [11]
    A.F. Falk and M.E. Peskin, Production, decay and polarization of excited heavy hadrons, Phys. Rev. D 49 (1994) 3320 [hep-ph/9308241] [INSPIRE].ADSGoogle Scholar
  12. [12]
    ALEPH collaboration, D. Buskulic et al., Measurement of Λb polarization in Z decays, Phys. Lett. B 365 (1996) 437 [INSPIRE].
  13. [13]
    OPAL collaboration, G. Abbiendi et al., Measurement of the average polarization of b baryons in hadronic Z 0 decays, Phys. Lett. B 444 (1998) 539 [hep-ex/9808006] [INSPIRE].
  14. [14]
    DELPHI collaboration, P. Abreu et al., Λb polarization in Z 0 decays at LEP, Phys. Lett. B 474 (2000) 205 [INSPIRE].
  15. [15]
    ATLAS collaboration, Measurement of the cross section of high transverse momentum \( Z\to b\overline{b} \) production in proton-proton collisions at \( \sqrt{s}=8 \) TeV with the ATLAS detector, Phys. Lett. B 738 (2014) 25 [arXiv:1404.7042] [INSPIRE].
  16. [16]
    W.G.D. Dharmaratna and G.R. Goldstein, Single quark polarization in quantum chromodynamics subprocesses, Phys. Rev. D 53 (1996) 1073 [INSPIRE].ADSGoogle Scholar
  17. [17]
    LHCb collaboration, Measurements of the Λb0J/ψΛ decay amplitudes and the Λb0 polarisation in pp collisions at \( \sqrt{s}=7 \) TeV, Phys. Lett. B 724 (2013) 27 [arXiv:1302.5578] [INSPIRE].
  18. [18]
    ATLAS collaboration, Measurement of the parity-violating asymmetry parameter α b and the helicity amplitudes for the decay Λb0J/ψ + Λ0 with the ATLAS detector, Phys. Rev. D 89 (2014) 092009 [arXiv:1404.1071] [INSPIRE].
  19. [19]
    M. Ivova Rikova, Measurement of the Λb Polarization with pp collisions at 7 TeV, CERN-THESIS-2013-218 (2013).
  20. [20]
    M. Jezabek, K. Rybicki and R. Rylko, Experimental study of spin effects in hadroproduction and decay of Λc+, Phys. Lett. B 286 (1992) 175 [INSPIRE].CrossRefADSGoogle Scholar
  21. [21]
    E791 collaboration, E.M. Aitala et al., Multidimensional resonance analysis of Λc+pK π+, Phys. Lett. B 471 (2000) 449 [hep-ex/9912003] [INSPIRE].
  22. [22]
    J.G. Korner, M. Krämer and D. Pirjol, Heavy baryons, Prog. Part. Nucl. Phys. 33 (1994) 787 [hep-ph/9406359] [INSPIRE].CrossRefADSGoogle Scholar
  23. [23]
    Heavy Flavor Averaging Group (HFAG) collaboration, Y. Amhis et al., Averages of b-hadron, c-hadron and τ -lepton properties as of summer 2014, arXiv:1412.7515 [INSPIRE].
  24. [24]
    CDF collaboration, T. Aaltonen et al., Observation of the Ωb and measurement of the properties of the Ξb and Ωb, Phys. Rev. D 80 (2009) 072003 [arXiv:0905.3123] [INSPIRE].
  25. [25]
    H.-Y. Cheng, Nonleptonic weak decays of bottom baryons, Phys. Rev. D 56 (1997) 2799 [hep-ph/9612223] [INSPIRE].ADSGoogle Scholar
  26. [26]
    L. Gladilin, Fragmentation fractions of c and b quarks into charmed hadrons at LEP, Eur. Phys. J. C 75 (2015) 19 [arXiv:1404.3888] [INSPIRE].CrossRefADSGoogle Scholar
  27. [27]
    CDF collaboration, T. Aaltonen et al., First measurement of the ratio of branching fractions \( B\left({\Lambda}_{{}^b}^0\to {\varLambda}_{{}^c}^{+}{\mu}^{-}{\overline{\nu}}_{\mu}\right)/B\left({\Lambda}_{{}^b}^0\to {\Lambda}_{{}^c}^{+}{\pi}^{-}\right) \), Phys. Rev. D 79 (2009) 032001 [arXiv:0810.3213] [INSPIRE].
  28. [28]
    CMS collaboration, Measurement of the Λb cross section and the \( {\overline{\Lambda}}_b \) to Λb ratio with J/ψΛ decays in pp collisions at \( \sqrt{s}=7 \) TeV, Phys. Lett. B 714 (2013) 136 [arXiv:1205.0594] [INSPIRE].
  29. [29]
    LHCb collaboration, Measurement of b-hadron production fractions in 7 TeV pp collisions, Phys. Rev. D 85 (2012) 032008 [arXiv:1111.2357] [INSPIRE].
  30. [30]
    LHCb collaboration, Study of the kinematic dependences of Λb0 production in pp collisions and a measurement of the Λb0 → Λc+ π branching fraction, JHEP 08 (2014) 143 [arXiv:1405.6842] [INSPIRE].
  31. [31]
    M. Cacciari and P. Nason, Is there a significant excess in bottom hadroproduction at the Tevatron?, Phys. Rev. Lett. 89 (2002) 122003 [hep-ph/0204025] [INSPIRE].CrossRefADSGoogle Scholar
  32. [32]
    CDF collaboration, T. Aaltonen et al., First observation of heavy baryons Σb andb*, Phys. Rev. Lett. 99 (2007) 202001 [arXiv:0706.3868] [INSPIRE].
  33. [33]
    CDF collaboration, T. Aaltonen et al., Measurement of the masses and widths of the bottom baryonsb± andb* ±, Phys. Rev. D 85 (2012) 092011 [arXiv:1112.2808] [INSPIRE].
  34. [34]
    A. Andronic, F. Beutler, P. Braun-Munzinger, K. Redlich and J. Stachel, Statistical hadronization of heavy flavor quarks in elementary collisions: Successes and failures, Phys. Lett. B 678 (2009) 350 [arXiv:0904.1368] [INSPIRE].CrossRefADSGoogle Scholar
  35. [35]
    T. Sjöstrand, S. Mrenna and P.Z. Skands, PYTHIA 6.4 physics and manual, JHEP 05 (2006) 026 [hep-ph/0603175] [INSPIRE].CrossRefADSGoogle Scholar
  36. [36]
    P.Z. Skands, Tuning Monte Carlo generators: the Perugia tunes, Phys. Rev. D 82 (2010) 074018 [arXiv:1005.3457] [INSPIRE].ADSGoogle Scholar
  37. [37]
    P. Skands, S. Carrazza and J. Rojo, Tuning PYTHIA 8.1: the Monash 2013 tune, Eur. Phys. J. C 74 (2014) 3024 [arXiv:1404.5630] [INSPIRE].CrossRefADSGoogle Scholar
  38. [38]
    A. Adamov and G.R. Goldstein, Excited state contributions to the heavy baryon fragmentation functions in a quark-diquark model, Phys. Rev. D 64 (2001) 014021 [hep-ph/0009300] [INSPIRE].ADSGoogle Scholar
  39. [39]
    E791 collaboration, E.M. Aitala et al., Mass splitting and production ofc0 andc+ + measured in 500 GeV π -N interactions, Phys. Lett. B 379 (1996) 292 [hep-ex/9604007] [INSPIRE].
  40. [40]
    DELPHI collaboration, M. Feindt et al., First evidence for Σb andb* baryons, DELPHI-95-107 (1995).
  41. [41]
    M. Feindt, Heavy quark spectroscopy at LEP, CERN-PPE-95-139 (1995).
  42. [42]
    O. Podobrin, B-hadron production at LEP, Nucl. Phys. Proc. Suppl. 50 (1996) 90.CrossRefADSGoogle Scholar
  43. [43]
    CLEO collaboration, G. Brandenburg et al., Observation of two excited charmed baryons decaying into \( {\Lambda}_{{}^c}^{+}{\pi}^{\pm } \) , Phys. Rev. Lett. 78 (1997) 2304 [INSPIRE].
  44. [44]
    Y.-Q. Chen and M.B. Wise, Remark on charm quark fragmentation to D ∗∗ mesons, Phys. Rev. D 50 (1994) 4706 [hep-ph/9404240] [INSPIRE].ADSGoogle Scholar
  45. [45]
    T.C. Yuan, Helicity probabilities for heavy quark fragmentation into excited mesons, Phys. Rev. D 51 (1995) 4830 [hep-ph/9407341] [INSPIRE].ADSGoogle Scholar
  46. [46]
    J.K. Elwood, Excited charmed baryon decays and their implications for fragmentation parameters, Phys. Rev. D 53 (1996) 4866 [hep-ph/9511241] [INSPIRE].ADSGoogle Scholar
  47. [47]
    C.-K. Chow, Qualitative aspects of polarization distributions in excited heavy hadron productions, hep-ph/9609514 [INSPIRE].
  48. [48]
    J.P. Ma, Revisiting spin alignment of heavy mesons in its inclusive production, Nucl. Phys. B 622 (2002) 416 [hep-ph/0111237] [INSPIRE].CrossRefADSGoogle Scholar
  49. [49]
    Belle collaboration, V. Balagura et al., Observation of D s1(2536)+D + π K + and angular decomposition of D s1(2536)+ → D ∗ + K S0, Phys. Rev. D 77 (2008) 032001 [arXiv:0709.4184] [INSPIRE].
  50. [50]
    J.G. Korner, A. Pilaftsis and M.M. Tung, One loop QCD mass effects in the production of polarized bottom and top quarks, Z. Phys. C 63 (1994) 575 [hep-ph/9311332] [INSPIRE].ADSGoogle Scholar
  51. [51]
    Particle Data Group collaboration, K.A. Olive et al., Review of particle physics, Chin. Phys. C 38 (2014) 090001 [INSPIRE].
  52. [52]
    M. Baumgart and B. Tweedie, Transverse top quark polarization and the \( t\overline{t} \) forward-backward asymmetry, JHEP 08 (2013) 072 [arXiv:1303.1200] [INSPIRE].CrossRefADSGoogle Scholar
  53. [53]
    ALICE collaboration, Measurement of charm production at central rapidity in proton-proton collisions at \( \sqrt{s} = 2.76 \) TeV, JHEP 07 (2012) 191 [arXiv:1205.4007] [INSPIRE].
  54. [54]
    CLEO collaboration, G. Brandenburg et al., Continuum charged D spin alignment at \( \sqrt{s}=10.5 \) GeV,Phys. Rev. D 58 (1998) 052003 [hep-ex/9802022] [INSPIRE].
  55. [55]
    T.-M. Yan, H.-Y. Cheng, C.-Y. Cheung, G.-L. Lin, Y.C. Lin and H.-L. Yu, Heavy quark symmetry and chiral dynamics, Phys. Rev. D 46 (1992) 1148 [Erratum ibid. D 55 (1997) 5851] [INSPIRE].
  56. [56]
    G. Bonvicini and L. Randall, Optimized variables for the study of Λb polarization, Phys. Rev. Lett. 73 (1994) 392 [hep-ph/9401299] [INSPIRE].CrossRefADSGoogle Scholar
  57. [57]
    B. Mele, Lepton spectra and the b polarization at LEP, Mod. Phys. Lett. A 9 (1994) 1239 [hep-ph/9403302] [INSPIRE].CrossRefADSGoogle Scholar
  58. [58]
    ALEPH collaboration, D. Buskulic et al., Measurement of Λ polarization from Z decays, Phys. Lett. B 374 (1996) 319 [INSPIRE].
  59. [59]
    ALEPH collaboration, Update of Λ polarization from Z decays, CERN-OPEN-99-328 (1997).
  60. [60]
    OPAL collaboration, K. Ackerstaff et al., Polarization and forward-backward asymmetry of Λ baryons in hadronic Z 0 decays, Eur. Phys. J. C 2 (1998) 49 [hep-ex/9708027] [INSPIRE].
  61. [61]
    G.R. Goldstein, Polarization of inclusively produced Λc in a QCD based hybrid model, hep-ph/9907573 [INSPIRE].
  62. [62]
    A.V. Manohar and M.B. Wise, Inclusive semileptonic B and polarized Λb decays from QCD, Phys. Rev. D 49 (1994) 1310 [hep-ph/9308246] [INSPIRE].ADSGoogle Scholar
  63. [63]
    A. Czarnecki, M. Jezabek, J.G. Korner and J.H. Kuhn, QCD corrections to decays of polarized charm and bottom quarks, Phys. Rev. Lett. 73 (1994) 384 [hep-ph/9312249] [INSPIRE].CrossRefADSGoogle Scholar
  64. [64]
    A. Czarnecki and M. Jezabek, Distributions of leptons in decays of polarized heavy quarks, Nucl. Phys. B 427 (1994) 3 [hep-ph/9402326] [INSPIRE].CrossRefADSGoogle Scholar
  65. [65]
    CMS collaboration, Algorithms for b jet identification in CMS, CMS-PAS-BTV-09-001 (2009).
  66. [66]
    LHCb collaboration, Precision measurement of the ratio of the Λb0 to \( {\overline{B}}^0 \) lifetimes, Phys. Lett. B 734 (2014) 122 [arXiv:1402.6242] [INSPIRE].
  67. [67]
    ALEPH collaboration, A. Heister et al., Study of the fragmentation of b quarks into B mesons at the Z peak, Phys. Lett. B 512 (2001) 30 [hep-ex/0106051] [INSPIRE].
  68. [68]
    DELPHI collaboration, J. Abdallah et al., A study of the b-quark fragmentation function with the DELPHI detector at LEP I and an averaged distribution obtained at the Z Pole, Eur. Phys. J. C 71 (2011) 1557 [arXiv:1102.4748] [INSPIRE].
  69. [69]
    OPAL collaboration, G. Abbiendi et al., Inclusive analysis of the b quark fragmentation function in Z decays at LEP, Eur. Phys. J. C 29 (2003) 463 [hep-ex/0210031] [INSPIRE].
  70. [70]
    SLD collaboration, K. Abe et al., Measurement of the b quark fragmentation function in Z 0 decays, Phys. Rev. D 65 (2002) 092006 [Erratum ibid. D 66 (2002) 079905] [hep-ex/0202031] [INSPIRE].
  71. [71]
    ATLAS collaboration, Search for pair-produced third-generation squarks decaying via charm quarks or in compressed supersymmetric scenarios in pp collisions at \( \sqrt{s} = 8 \) TeV with the ATLAS detector, Phys. Rev. D 90 (2014) 052008 [arXiv:1407.0608] [INSPIRE].
  72. [72]
    ATLAS collaboration, Search for scalar charm quark pair production in pp collisions at \( \sqrt{s} = 8 \) TeV with the ATLAS detector,Phys. Rev. Lett. 114 (2015) 161801 [arXiv:1501.01325] [INSPIRE].
  73. [73]
    D0 collaboration, V.M. Abazov et al., Measurement of the Λb0 lifetime using semileptonic decays, Phys. Rev. Lett. 99 (2007) 182001 [arXiv:0706.2358] [INSPIRE].
  74. [74]
    O. Gedalia et al., Top B physics at the LHC, Phys. Rev. Lett. 110 (2013) 232002 [arXiv:1212.4611] [INSPIRE].CrossRefADSGoogle Scholar
  75. [75]
    CMS collaboration, Description and performance of track and primary-vertex reconstruction with the CMS tracker, 2014 JINST 9 P10009 [arXiv:1405.6569] [INSPIRE].
  76. [76]
    Belle collaboration, A. Zupanc et al., Measurement of the branching fraction ℬ(Λc+ → pK π +), Phys. Rev. Lett. 113 (2014) 042002 [arXiv:1312.7826] [INSPIRE].
  77. [77]
    CMS collaboration, Measurement of the B+ production cross section in pp collisions at \( \sqrt{s}=7 \) TeV,Phys. Rev. Lett. 106 (2011) 112001 [arXiv:1101.0131] [INSPIRE].
  78. [78]
    CMS collaboration, Measurement of the B s0 production cross section with B s0J/ψ ϕ decays in pp collisions at \( \sqrt{s}=7 \) TeV, Phys. Rev. D 84 (2011) 052008 [arXiv:1106.4048] [INSPIRE].
  79. [79]
    CMS collaboration, Measurement of associated W + charm production in pp collisions at \( \sqrt{s}=7 \) TeV,JHEP 02 (2014) 013 [arXiv:1310.1138] [INSPIRE].
  80. [80]
    ATLAS collaboration, Measurement of the production of a W boson in association with a charm quark in pp collisions at \( \sqrt{s}=7 \) TeV with the ATLAS detector, JHEP 05 (2014) 068 [arXiv:1402.6263] [INSPIRE].
  81. [81]
    S. Dambach, U. Langenegger and A. Starodumov, Neutrino reconstruction with topological information, Nucl. Instrum. Meth. A 569 (2006) 824 [hep-ph/0607294] [INSPIRE].CrossRefADSGoogle Scholar
  82. [82]
    LHCb collaboration, Determination of the quark coupling strength |V ub| using baryonic decays, Nature Phys. 11 (2015) 743 [arXiv:1504.01568] [INSPIRE].
  83. [83]
    CMS collaboration, Measurement of the top quark mass using the B-hadron lifetime technique, CMS-PAS-TOP-12-030 (2013).
  84. [84]
    M. Czakon and A. Mitov, Top++: a program for the calculation of the top-pair cross-section at hadron colliders, Comput. Phys. Commun. 185 (2014) 2930 [arXiv:1112.5675] [INSPIRE].CrossRefADSGoogle Scholar
  85. [85]
    R. Gavin, Y. Li, F. Petriello and S. Quackenbush, FEWZ 2.0: a code for hadronic Z production at next-to-next-to-leading order, Comput. Phys. Commun. 182 (2011) 2388 [arXiv:1011.3540] [INSPIRE].CrossRefADSGoogle Scholar
  86. [86]
    Y. Li and F. Petriello, Combining QCD and electroweak corrections to dilepton production in FEWZ, Phys. Rev. D 86 (2012) 094034 [arXiv:1208.5967] [INSPIRE].ADSGoogle Scholar
  87. [87]
    P. Kant et al., HatHor for single top-quark production: updated predictions and uncertainty estimates for single top-quark production in hadronic collisions, Comput. Phys. Commun. 191 (2015) 74 [arXiv:1406.4403] [INSPIRE].MathSciNetCrossRefADSGoogle Scholar
  88. [88]
    J. Alwall, M. Herquet, F. Maltoni, O. Mattelaer and T. Stelzer, MadGraph 5: going beyond, JHEP 06 (2011) 128 [arXiv:1106.0522] [INSPIRE].CrossRefADSGoogle Scholar
  89. [89]
    J. D’Hondt et al., Fitting of event topologies with external kinematic constraints in CMS, CMS-NOTE-2006-023 (2006).
  90. [90]
    J. Erdmann et al., A likelihood-based reconstruction algorithm for top-quark pairs and the KLFitter framework, Nucl. Instrum. Meth. A 748 (2014) 18 [arXiv:1312.5595] [INSPIRE].CrossRefADSGoogle Scholar
  91. [91]
    B.A. Betchart, R. Demina and A. Harel, Analytic solutions for neutrino momenta in decay of top quarks, Nucl. Instrum. Meth. A 736 (2014) 169 [arXiv:1305.1878] [INSPIRE].CrossRefADSGoogle Scholar
  92. [92]
    ATLAS collaboration, Measurements of normalized differential cross sections for tt production in pp collisions at \( \sqrt{s}=7 \) TeV using the ATLAS detector, Phys. Rev. D 90 (2014) 072004 [arXiv:1407.0371] [INSPIRE].
  93. [93]
    CMS collaboration, Measurement of the differential cross section for top quark pair production in pp collisions at \( \sqrt{s}=8 \) TeV, arXiv:1505.04480 [INSPIRE].
  94. [94]
    CMS collaboration, Measurement of the inclusive and differential \( t\overline{t} \) production cross sections in lepton + jets final states at 13 TeV, CMS-PAS-TOP-15-005 (2015).
  95. [95]
    CMS collaboration, Measurement of the t-channel single top quark production cross section in pp collisions at \( \sqrt{s}=7 \) TeV, Phys. Rev. Lett. 107 (2011) 091802 [arXiv:1106.3052] [INSPIRE].
  96. [96]
    J.D. Bjorken, Spin dependent decays of the Λc, Phys. Rev. D 40 (1989) 1513 [INSPIRE].ADSGoogle Scholar
  97. [97]
    ATLAS collaboration, dE/dx measurement in the ATLAS Pixel detector and its use for particle identification, ATLAS-CONF-2011-016 (2011).
  98. [98]
    ATLAS collaboration, Particle identification performance of the ATLAS transition radiation tracker, ATLAS-CONF-2011-128 (2011).
  99. [99]
    A. Giammanco, Particle identification with energy loss in the CMS silicon strip tracker, CMS-NOTE-2008-005 (2008).
  100. [100]
    CMS collaboration, CMS tracking performance results from early LHC operation, Eur. Phys. J. C 70 (2010) 1165 [arXiv:1007.1988] [INSPIRE].
  101. [101]
    A. Zagozdzinska, K. T. Pozniak, R. Romaniuk and P. Zalewski, Heavy stable charged particles search by RPC system at CMS detector at LHC accelerator at CERN, Proc. SPIE 8903 (2013) 89031K.CrossRefADSGoogle Scholar
  102. [102]
    CMS collaboration, Measurement of the top-quark mass in \( t\overline{t} \) events with lepton+jets final states in pp collisions at \( \sqrt{s}=8 \) TeV, CMS-PAS-TOP-14-001 (2014).
  103. [103]
    CMS collaboration, Identification of b-quark jets with the CMS experiment, 2013 JINST 8 P04013 [arXiv:1211.4462] [INSPIRE].
  104. [104]
    LHCb collaboration, Observation of two new Ξb baryon resonances, Phys. Rev. Lett. 114 (2015) 062004 [arXiv:1411.4849] [INSPIRE].
  105. [105]
    CMS collaboration, Observation of a new Ξb baryon, Phys. Rev. Lett. 108 (2012) 252002 [arXiv:1204.5955] [INSPIRE].
  106. [106]
    M.A. Ivanov, J.G. Korner, V.E. Lyubovitskij and A.G. Rusetsky, Exclusive nonleptonic bottom to charm baryon decays including nonfactorizable contributions, Mod. Phys. Lett. A 13 (1998) 181 [hep-ph/9709325] [INSPIRE].CrossRefADSGoogle Scholar
  107. [107]
    M.A. Ivanov, J.G. Korner, V.E. Lyubovitskij and A.G. Rusetsky, Exclusive nonleptonic decays of bottom and charm baryons in a relativistic three quark model: evaluation of nonfactorizing diagrams, Phys. Rev. D 57 (1998) 5632 [hep-ph/9709372] [INSPIRE].ADSGoogle Scholar
  108. [108]
    J.-P. Lee, C. Liu and H.S. Song, Analysis of Λb → Λc weak decays in heavy quark effective theory, Phys. Rev. D 58 (1998) 014013 [hep-ph/9803489] [INSPIRE].ADSGoogle Scholar
  109. [109]
    X.H. Guo, Λb → Λc P (V ) nonleptonic weak decays, Mod. Phys. Lett. A 13 (1998) 2265 [hep-ph/9805304] [INSPIRE].CrossRefADSGoogle Scholar
  110. [110]
    R. Mohanta, A.K. Giri, M.P. Khanna, M. Ishida, S. Ishida and M. Oda, Hadronic weak decays of Λb baryon in the covariant oscillator quark model, Prog. Theor. Phys. 101 (1999) 959 [hep-ph/9904324] [INSPIRE].CrossRefADSGoogle Scholar
  111. [111]
    H.-W. Ke, X.-Q. Li and Z.-T. Wei, Diquarks and Λb → Λc weak decays, Phys. Rev. D 77 (2008) 014020 [arXiv:0710.1927] [INSPIRE].ADSGoogle Scholar
  112. [112]
    T. Gutsche, M.A. Ivanov, J.G. Körner, V.E. Lyubovitskij and P. Santorelli, Polarization effects in the cascade decay Λb → Λ(→ ) + J/ψ(→ ℓ+) in the covariant confined quark model, Phys. Rev. D 88 (2013) 114018 [arXiv:1309.7879] [INSPIRE].ADSGoogle Scholar
  113. [113]
    Fayyazuddin and Riazuddin, Two-body nonleptonic Λb decays in quark model with factorization ansatz, Phys. Rev. D 58 (1998) 014016 [hep-ph/9802326] [INSPIRE].
  114. [114]
    C.-H. Chou, H.-H. Shih, S.-C. Lee and H.-n. Li, Λb → ΛJ/ψ decay in perturbative QCD, Phys. Rev. D 65 (2002) 074030 [hep-ph/0112145] [INSPIRE].ADSGoogle Scholar
  115. [115]
    Z.J. Ajaltouni, E. Conte and O. Leitner, Λb decays into Λ-vector, Phys. Lett. B 614 (2005) 165 [hep-ph/0412116] [INSPIRE].CrossRefADSGoogle Scholar
  116. [116]
    Z.-T. Wei, H.-W. Ke and X.-Q. Li, Evaluating decay rates and asymmetries of Λb into light baryons in LFQM, Phys. Rev. D 80 (2009) 094016 [arXiv:0909.0100] [INSPIRE].ADSGoogle Scholar
  117. [117]
    L. Mott and W. Roberts, Rare dileptonic decays of Λb in a quark model, Int. J. Mod. Phys. A 27 (2012) 1250016 [arXiv:1108.6129] [INSPIRE].CrossRefADSGoogle Scholar
  118. [118]
    CDF collaboration, T. Aaltonen et al., Measurements of the properties of Λc(2595), Λc(2625), Σc(2455) and Σc(2520) baryons, Phys. Rev. D 84 (2011) 012003 [arXiv:1105.5995] [INSPIRE].
  119. [119]
    Belle collaboration, S.H. Lee et al., Measurements of the masses and widths of the Σc(2455)0/++ and Σc(2520)0/++ baryons, Phys. Rev. D 89 (2014) 091102 [arXiv:1404.5389] [INSPIRE].
  120. [120]
    LHCb collaboration, Prompt charm production in pp collisions at \( \sqrt{s}=7 \) TeV, Nucl. Phys. B 871 (2013) 1 [arXiv:1302.2864] [INSPIRE].
  121. [121]
    LHCb collaboration, Precision measurement of the mass and lifetime of the Ξb baryon, Phys. Rev. Lett. 113 (2014) 242002 [arXiv:1409.8568] [INSPIRE].
  122. [122]
    D. Ebert, R.N. Faustov and V.O. Galkin, Semileptonic decays of heavy baryons in the relativistic quark model, Phys. Rev. D 73 (2006) 094002 [hep-ph/0604017] [INSPIRE].ADSGoogle Scholar
  123. [123]
    V. Barone, A. Drago and P.G. Ratcliffe, Transverse polarisation of quarks in hadrons, Phys. Rept. 359 (2002) 1 [hep-ph/0104283] [INSPIRE].zbMATHCrossRefADSGoogle Scholar
  124. [124]
    D. Boer and P.J. Mulders, Time reversal odd distribution functions in leptoproduction, Phys. Rev. D 57 (1998) 5780 [hep-ph/9711485] [INSPIRE].ADSGoogle Scholar
  125. [125]
    K. Chen, G.R. Goldstein, R.L. Jaffe and X.-D. Ji, Probing quark fragmentation functions for spin 1/2 baryon production in unpolarized e + e annihilation, Nucl. Phys. B 445 (1995) 380 [hep-ph/9410337] [INSPIRE].CrossRefADSGoogle Scholar
  126. [126]
    R.L. Jaffe and X.-D. Ji, Novel quark fragmentation functions and the nucleons transversity distribution, Phys. Rev. Lett. 71 (1993) 2547 [hep-ph/9307329] [INSPIRE].CrossRefADSGoogle Scholar
  127. [127]
    J. Collins, Foundations of perturbative QCD, Cambridge University Press, Cambridge U.K. (2011).CrossRefGoogle Scholar
  128. [128]
    M. Boglione and P.J. Mulders, Time reversal odd fragmentation and distribution functions in pp and ep single spin asymmetries, Phys. Rev. D 60 (1999) 054007 [hep-ph/9903354] [INSPIRE].ADSGoogle Scholar
  129. [129]
    B. Mele and P. Nason, The fragmentation function for heavy quarks in QCD, Nucl. Phys. B 361 (1991) 626 [INSPIRE].CrossRefADSGoogle Scholar
  130. [130]
    R.L. Jaffe and L. Randall, Heavy quark fragmentation into heavy mesons, Nucl. Phys. B 412 (1994) 79 [hep-ph/9306201] [INSPIRE].CrossRefADSGoogle Scholar
  131. [131]
    M. Neubert, Factorization analysis for the fragmentation functions of hadrons containing a heavy quark, arXiv:0706.2136 [INSPIRE].
  132. [132]
    C.W. Bauer and E. Mereghetti, Heavy quark fragmenting jet functions, JHEP 04 (2014) 051 [arXiv:1312.5605] [INSPIRE].CrossRefADSGoogle Scholar
  133. [133]
    CLEO collaboration, P. Avery et al., Inclusive production of the charmed baryon Λc from e+eannihilations a \( \sqrt{s}=10.55 \) GeV, Phys. Rev. D 43 (1991) 3599 [INSPIRE].
  134. [134]
    Belle collaboration, R. Seuster et al., Charm hadrons from fragmentation and B decays in e+eannihilation at \( \sqrt{s}=10.6 \) GeV, Phys. Rev. D 73 (2006) 032002 [hep-ex/0506068] [INSPIRE].
  135. [135]
    BaBar collaboration, B. Aubert et al., Inclusive Λc+ production in e+eannihilations at \( \sqrt{s}=10.54 \) GeV and in ϒ(4S) decays,Phys. Rev. D 75 (2007) 012003 [hep-ex/0609004] [INSPIRE].
  136. [136]
    M. Cacciari, P. Nason and C. Oleari, A study of heavy flavored meson fragmentation functions in e + e annihilation, JHEP 04 (2006) 006 [hep-ph/0510032] [INSPIRE].CrossRefADSGoogle Scholar
  137. [137]
    K. Melnikov and A. Mitov, Perturbative heavy quark fragmentation function through O(α s2), Phys. Rev. D 70 (2004) 034027 [hep-ph/0404143] [INSPIRE].ADSGoogle Scholar
  138. [138]
    P. Nason and B.R. Webber, Scaling violation in e + e fragmentation functions: QCD evolution, hadronization and heavy quark mass effects, Nucl. Phys. B 421 (1994) 473 [Erratum ibid. B 480 (1996) 755] [INSPIRE].
  139. [139]
    M. Stratmann and W. Vogelsang, Next-to-leading order evolution of polarized and unpolarized fragmentation functions, Nucl. Phys. B 496 (1997) 41 [hep-ph/9612250] [INSPIRE].
  140. [140]
    X. Artru and M. Mekhfi, Transversely polarized parton densities, their evolution and their measurement, Z. Phys. C 45 (1990) 669 [INSPIRE].ADSGoogle Scholar
  141. [141]
    LHCb collaboration, Measurement of the fragmentation fraction ratio f s /f d and its dependence on B meson kinematics, JHEP 04 (2013) 001 [arXiv:1301.5286] [INSPIRE].

Copyright information

© The Author(s) 2015

Authors and Affiliations

  • Mario Galanti
    • 1
  • Andrea Giammanco
    • 2
    • 3
  • Yuval Grossman
    • 4
  • Yevgeny Kats
    • 5
    Email author
  • Emmanuel Stamou
    • 5
  • Jure Zupan
    • 6
  1. 1.Department of Physics and AstronomyUniversity of RochesterRochesterU.S.A.
  2. 2.Centre for Cosmology, Particle Physics and PhenomenologyUniversité catholique de LouvainLouvain-la-NeuveBelgium
  3. 3.National Institute of Chemical Physics and BiophysicsTallinnEstonia
  4. 4.Laboratory for Elementary-Particle PhysicsCornell UniversityIthacaU.S.A.
  5. 5.Department of Particle Physics and AstrophysicsWeizmann Institute of ScienceRehovotIsrael
  6. 6.Department of PhysicsUniversity of CincinnatiCincinnatiU.S.A.

Personalised recommendations