Searches for Λ0b and Ξ0b decays to K0spπ- and K0spK- final states with first observation of the Λ0b → K0spπ- decay

LHCb Collaboration; R. Aaij; B. Adeva; M. Adinolfi; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; S. Ali; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves; S. Amato; S. Amerio; Y. Amhis; L. Anderlini; J. Anderson; R. Andreassen; M. Andreotti; J. E. Andrews; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; M. Baalouch; S. Bachmann; J. J. Back; A. Badalov; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; V. Batozskaya; Th Bauer; S. Bifani; P. Griffith; P. Ilten; I. R. Kenyon; C. Lazzeroni; A. Mazurov; J. McCarthy; C. J. Parkinson; L. Pescatore; D. Popov; N. K. Watson

doi:10.1007/JHEP04(2014)087

Searches for Λ⁰_b and Ξ⁰_b decays to K⁰_spπ^- and K⁰_spK^- final states with first observation of the Λ⁰_b → K⁰_spπ^- decay

LHCb Collaboration, R. Aaij, B. Adeva, M. Adinolfi, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves, S. Amato, S. Amerio, Y. Amhis, L. Anderlini, J. Anderson, R. Andreassen, M. AndreottiJ. E. Andrews, R. B. Appleby, O. Aquines Gutierrez, F. Archilli, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, M. Baalouch, S. Bachmann, J. J. Back, A. Badalov, V. Balagura, W. Baldini, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, V. Batozskaya, Th Bauer, S. Bifani, P. Griffith, P. Ilten, I. R. Kenyon, C. Lazzeroni, A. Mazurov, J. McCarthy, C. J. Parkinson, L. Pescatore, D. Popov, N. K. Watson

Physics and Astronomy

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Abstract

A search for previously unobserved decays of beauty baryons to the final states K⁰_spπ^- and K⁰_spK^- is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb^-1 of pp collisions. The Λ⁰_b → K^-0 pπ^- decay is observed with a significance of 8.6σ, with branching fraction B(Λ⁰_b → K^-0 pπ⁻) = (1.26 ± 0.19 ± 0.09 ± 0.34 ± 0.05) × 10⁻⁵, where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f _Λ⁰_b/f_d, and from the branching fraction of the B⁰ → K⁰π⁺π^- normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving A_CP (Λ⁰_b → K^-0 pπ⁻) = 0.22 ± 0.13 (stat) ± 0.03 (syst). No significant signals are seen for Λ⁰_b → K⁰_spK^- decays, Ξ⁰_b decays to both the K⁰_spπ^- and K⁰_spK^- final states, and the Λ⁰_b → D^-_s(→ K⁰_sK^-)p decay, and upper limits on their branching fractions are reported.

Original language	English
Article number	87
Number of pages	24
Journal	Journal of High Energy Physics
Volume	2014
Issue number	4
DOIs	https://doi.org/10.1007/JHEP04(2014)087
Publication status	Published - 11 Apr 2014

Keywords

B physics
Branching fraction
Flavor physics
Hadron-hadron scattering

ASJC Scopus subject areas

Nuclear and High Energy Physics

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Cite this

LHCb Collaboration, Aaij, R., Adeva, B., Adinolfi, M., Affolder, A., Ajaltouni, Z., Albrecht, J., Alessio, F., Alexander, M., Ali, S., Alkhazov, G., Alvarez Cartelle, P., Alves, A. A., Amato, S., Amerio, S., Amhis, Y., Anderlini, L., Anderson, J., Andreassen, R., ... Watson, N. K. (2014). Searches for Λ⁰_b and Ξ⁰_b decays to K⁰_spπ^- and K⁰_spK^- final states with first observation of the Λ⁰_b → K⁰_spπ^- decay. Journal of High Energy Physics, 2014(4), Article 87. https://doi.org/10.1007/JHEP04(2014)087

@article{ea8cbb46f7014bb88fe8e9677436c1f9,

title = "Searches for Λ0b and Ξ0b decays to K0spπ- and K0spK- final states with first observation of the Λ0b → K0spπ- decay",

abstract = "A search for previously unobserved decays of beauty baryons to the final states K0spπ- and K0spK- is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb-1 of pp collisions. The Λ0b → K-0 pπ- decay is observed with a significance of 8.6σ, with branching fraction B(Λ0b → K-0 pπ−) = (1.26 ± 0.19 ± 0.09 ± 0.34 ± 0.05) × 10−5, where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f Λ0b/fd, and from the branching fraction of the B0 → K0π+π- normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving ACP (Λ0b → K-0 pπ−) = 0.22 ± 0.13 (stat) ± 0.03 (syst). No significant signals are seen for Λ0b → K0spK- decays, Ξ0b decays to both the K0spπ- and K0spK- final states, and the Λ0b → D-s(→ K0sK-)p decay, and upper limits on their branching fractions are reported.",

keywords = "B physics, Branching fraction, Flavor physics, Hadron-hadron scattering",

author = "{LHCb Collaboration} and R. Aaij and B. Adeva and M. Adinolfi and A. Affolder and Z. Ajaltouni and J. Albrecht and F. Alessio and M. Alexander and S. Ali and G. Alkhazov and {Alvarez Cartelle}, P. and Alves, {A. A.} and S. Amato and S. Amerio and Y. Amhis and L. Anderlini and J. Anderson and R. Andreassen and M. Andreotti and Andrews, {J. E.} and Appleby, {R. B.} and {Aquines Gutierrez}, O. and F. Archilli and A. Artamonov and M. Artuso and E. Aslanides and G. Auriemma and M. Baalouch and S. Bachmann and Back, {J. J.} and A. Badalov and V. Balagura and W. Baldini and Barlow, {R. J.} and C. Barschel and S. Barsuk and W. Barter and V. Batozskaya and Th Bauer and S. Bifani and P. Griffith and P. Ilten and Kenyon, {I. R.} and C. Lazzeroni and A. Mazurov and J. McCarthy and Parkinson, {C. J.} and L. Pescatore and D. Popov and Watson, {N. K.}",

year = "2014",

month = apr,

day = "11",

doi = "10.1007/JHEP04(2014)087",

language = "English",

volume = "2014",

journal = "Journal of High Energy Physics",

issn = "1126-6708",

publisher = "Springer",

number = "4",

}

LHCb Collaboration, Aaij, R, Adeva, B, Adinolfi, M, Affolder, A, Ajaltouni, Z, Albrecht, J, Alessio, F, Alexander, M, Ali, S, Alkhazov, G, Alvarez Cartelle, P, Alves, AA, Amato, S, Amerio, S, Amhis, Y, Anderlini, L, Anderson, J, Andreassen, R, Andreotti, M, Andrews, JE, Appleby, RB, Aquines Gutierrez, O, Archilli, F, Artamonov, A, Artuso, M, Aslanides, E, Auriemma, G, Baalouch, M, Bachmann, S, Back, JJ, Badalov, A, Balagura, V, Baldini, W, Barlow, RJ, Barschel, C, Barsuk, S, Barter, W, Batozskaya, V, Bauer, T, Bifani, S, Griffith, P, Ilten, P, Kenyon, IR, Lazzeroni, C, Mazurov, A, McCarthy, J, Parkinson, CJ, Pescatore, L, Popov, D & Watson, NK 2014, 'Searches for Λ⁰_b and Ξ⁰_b decays to K⁰_spπ^- and K⁰_spK^- final states with first observation of the Λ⁰_b → K⁰_spπ^- decay', Journal of High Energy Physics, vol. 2014, no. 4, 87. https://doi.org/10.1007/JHEP04(2014)087

TY - JOUR

T1 - Searches for Λ0b and Ξ0b decays to K0spπ- and K0spK- final states with first observation of the Λ0b → K0spπ- decay

AU - LHCb Collaboration

AU - Aaij, R.

AU - Adeva, B.

AU - Adinolfi, M.

AU - Affolder, A.

AU - Ajaltouni, Z.

AU - Albrecht, J.

AU - Alessio, F.

AU - Alexander, M.

AU - Ali, S.

AU - Alkhazov, G.

AU - Alvarez Cartelle, P.

AU - Alves, A. A.

AU - Amato, S.

AU - Amerio, S.

AU - Amhis, Y.

AU - Anderlini, L.

AU - Anderson, J.

AU - Andreassen, R.

AU - Andreotti, M.

AU - Andrews, J. E.

AU - Appleby, R. B.

AU - Aquines Gutierrez, O.

AU - Archilli, F.

AU - Artamonov, A.

AU - Artuso, M.

AU - Aslanides, E.

AU - Auriemma, G.

AU - Baalouch, M.

AU - Bachmann, S.

AU - Back, J. J.

AU - Badalov, A.

AU - Balagura, V.

AU - Baldini, W.

AU - Barlow, R. J.

AU - Barschel, C.

AU - Barsuk, S.

AU - Barter, W.

AU - Batozskaya, V.

AU - Bauer, Th

AU - Bifani, S.

AU - Griffith, P.

AU - Ilten, P.

AU - Kenyon, I. R.

AU - Lazzeroni, C.

AU - Mazurov, A.

AU - McCarthy, J.

AU - Parkinson, C. J.

AU - Pescatore, L.

AU - Popov, D.

AU - Watson, N. K.

PY - 2014/4/11

Y1 - 2014/4/11

N2 - A search for previously unobserved decays of beauty baryons to the final states K0spπ- and K0spK- is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb-1 of pp collisions. The Λ0b → K-0 pπ- decay is observed with a significance of 8.6σ, with branching fraction B(Λ0b → K-0 pπ−) = (1.26 ± 0.19 ± 0.09 ± 0.34 ± 0.05) × 10−5, where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f Λ0b/fd, and from the branching fraction of the B0 → K0π+π- normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving ACP (Λ0b → K-0 pπ−) = 0.22 ± 0.13 (stat) ± 0.03 (syst). No significant signals are seen for Λ0b → K0spK- decays, Ξ0b decays to both the K0spπ- and K0spK- final states, and the Λ0b → D-s(→ K0sK-)p decay, and upper limits on their branching fractions are reported.

AB - A search for previously unobserved decays of beauty baryons to the final states K0spπ- and K0spK- is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb-1 of pp collisions. The Λ0b → K-0 pπ- decay is observed with a significance of 8.6σ, with branching fraction B(Λ0b → K-0 pπ−) = (1.26 ± 0.19 ± 0.09 ± 0.34 ± 0.05) × 10−5, where the uncertainties are statistical, systematic, from the ratio of fragmentation fractions f Λ0b/fd, and from the branching fraction of the B0 → K0π+π- normalisation channel, respectively. A first measurement is made of the CP asymmetry, giving ACP (Λ0b → K-0 pπ−) = 0.22 ± 0.13 (stat) ± 0.03 (syst). No significant signals are seen for Λ0b → K0spK- decays, Ξ0b decays to both the K0spπ- and K0spK- final states, and the Λ0b → D-s(→ K0sK-)p decay, and upper limits on their branching fractions are reported.

KW - B physics

KW - Branching fraction

KW - Flavor physics

KW - Hadron-hadron scattering

UR - http://www.scopus.com/inward/record.url?scp=84901757940&partnerID=8YFLogxK

U2 - 10.1007/JHEP04(2014)087

DO - 10.1007/JHEP04(2014)087

M3 - Article

AN - SCOPUS:84901757940

SN - 1126-6708

VL - 2014

JO - Journal of High Energy Physics

JF - Journal of High Energy Physics

IS - 4

M1 - 87

ER -