Signals consistent with the B-c(+)(2S) and B-c*(+)(2S) states are observed in proton-proton collisions at root s = 13 TeV, in an event sample corresponding to an integrated luminosity of 143 fb(-1), collected by the CMS experiment during the 2015-2018 LHC running periods. These excited (b) over barc states are observed in the B-c(+)pi(+)pi(-) invariant mass spectrum, with the ground state B-c(+) reconstructed through its decay to J/psi pi(+). The two states are reconstructed as two well-resolved peaks, separated in mass by 29.1 +/- 1.5(stat) +/- 0.7(syst) MeV. The observation of two peaks, rather than one, is established with a significance exceeding five standard deviations. The mass of the B-c(+)(2S) meson is measured to be 6871.0 +/- 1.2(stat) +/- 0.8(syst) +/- 0.8(B-c(+)) MeV, where the last term corresponds to the uncertainty in the world-average B-c(+) mass.

Observation of Two Excited Bc+ States and Measurement of the Bc+ (2S) Mass in pp Collisions at s =13 TeV / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Brandstetter, J., Dragicevic, M., Erö, J., Escalante Del Valle, A., Flechl, M., Frühwirth, R., Jeitler, M., Krammer, N., Krätschmer, I., Liko, D., Madlener, T., Mikulec, I., Rad, N., Schieck, J., Schöfbeck, ., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - STAMPA. - 122:13(2019). [10.1103/PhysRevLett.122.132001]

Observation of Two Excited Bc+ States and Measurement of the Bc+ (2S) Mass in pp Collisions at s =13 TeV

Creanza, D.;de Filippis, N.;di Florio, A.;Iaselli, G.;Maggi, G.;Pugliese, G.;
2019

Abstract

Signals consistent with the B-c(+)(2S) and B-c*(+)(2S) states are observed in proton-proton collisions at root s = 13 TeV, in an event sample corresponding to an integrated luminosity of 143 fb(-1), collected by the CMS experiment during the 2015-2018 LHC running periods. These excited (b) over barc states are observed in the B-c(+)pi(+)pi(-) invariant mass spectrum, with the ground state B-c(+) reconstructed through its decay to J/psi pi(+). The two states are reconstructed as two well-resolved peaks, separated in mass by 29.1 +/- 1.5(stat) +/- 0.7(syst) MeV. The observation of two peaks, rather than one, is established with a significance exceeding five standard deviations. The mass of the B-c(+)(2S) meson is measured to be 6871.0 +/- 1.2(stat) +/- 0.8(syst) +/- 0.8(B-c(+)) MeV, where the last term corresponds to the uncertainty in the world-average B-c(+) mass.
2019
Observation of Two Excited Bc+ States and Measurement of the Bc+ (2S) Mass in pp Collisions at s =13 TeV / Sirunyan, A.M., Tumasyan, A., Adam, W., Ambrogi, F., Bergauer, T., Brandstetter, J., Dragicevic, M., Erö, J., Escalante Del Valle, A., Flechl, M., Frühwirth, R., Jeitler, M., Krammer, N., Krätschmer, I., Liko, D., Madlener, T., Mikulec, I., Rad, N., Schieck, J., Schöfbeck, ., et al.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - STAMPA. - 122:13(2019). [10.1103/PhysRevLett.122.132001]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11589/207943
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