Observation of Bs0 mesons and measurement of the Bs0/B+ yield ratio in PbPb collisions at ▪ TeV

• Published in: Physics letters. B 2022-06, Vol.829, Article 137062
• Main Authors: Bergauer, T., Templ, S., Van Mulders, P., Moureaux, L., Postiau, N., Rebello Teles, P., Thiel, M., Shopova, M., Wang, Y., Chen, M., Qian, S.J., Florez, C., Mejia Guisao, J., Razis, P.A., Lehti, S., Siikonen, H., Malcles, J., Boudoul, G., Noll, D., Reithler, H., Schuler, S.C., Aldaya Martin, M., Brunner, D., Tonon, N., Iqbal, M.A., Katkov, I., Geralis, T., Gadallah, M.M.A., Karancsi, J., Bhardwaj, A., Bhattacharya, S., Pandey, S., De Palma, M., Silvestris, L., Lizzo, M., Ronchese, P., Bellan, R., Monaco, V., Pacher, L., Vazzoler, F., Uribe Estrada, C., Raicevic, N., Ahmad, A., Avati, V., Traczyk, P., Seixas, J., Kim, V., Kuznetsova, E., Gavrilov, V., Stepennov, A., Terkulov, A., Kardapoltsev, L., Kachanov, V., Tyurin, N., Ivanchenko, V., Milosevic, J., Gomez, G., Martinez Ruiz del Arbol, P., Rodrigo, T., Fiorendi, S., Gill, K., Gulhan, D., Rabady, D., Salfeld-Nebgen, J., Horisberger, R., Perrozzi, L., Wallny, R., Roy, A., Simsek, A.E., Flacher, H., Smith, V.J., Bell, K.W., Newbold, D.M., Cole, J.E., Landsberg, G., Flores, C., Würthwein, F., Vlimant, J.R., Jindariani, S., Lykken, J., Prokofyev, O., Hangal, D.A., Mestvirishvili, A., Wetzel, J., Baringer, P., Kim, D., Marini, A.C., Lesko, Z., Roozbahani, B., Ruchti, R., Wolf, M., Zygala, L., Roberts, J., Chou, J.P., Thomas, S., Johns, W., Maguire, C., Hakala, J., Poudyal, N., Ruggles, T.
• Format: Article
• Language: English
• Subjects: B mesons; CMS; Hadronization; Heavy flavor; Quark gluon plasma
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/j.physletb.2022.137062

The Bs0 and B+ production yields are measured in PbPb collisions at a center-of-mass energy per nucleon pair of 5.02 TeV. The data sample, collected with the CMS detector at the LHC, corresponds to an integrated luminosity of 1.7 nb−1. The mesons are reconstructed in the exclusive decay channels B→s0J/ψ(μ+μ−)ϕ(K+K−) and B→+J/ψ(μ+μ−)K+, in the transverse momentum range 7–50GeV/c and absolute rapidity 0–2.4. The Bs0 meson is observed with a statistical significance in excess of five standard deviations for the first time in nucleus-nucleus collisions. The measurements are performed as functions of the transverse momentum of the B mesons and of the PbPb collision centrality. The ratio of production yields of Bs0 and B+ is measured and compared to theoretical models that include quark recombination effects.