@article{8edb2beecda74d318b4175ef3e749da4,

title = "Observation of Y(1S) pair production in proton-proton collisions at √s=8 TeV",

abstract = "Pair production of Y(1S) mesons is observed at the LHC in proton-proton collisions at s=8 TeV by the CMS experiment in a data sample corresponding to an integrated luminosity of 20.7 fb−1. Both Y(1S) candidates are fully reconstructed via their decays to μ+μ−. The fiducial acceptance region is defined by an absolute Y(1S) rapidity smaller than 2.0. The fiducial cross section for the production of Y(1S) pairs, assuming that both mesons decay isotropically, is measured to be 68.8±12.7 (stat)±7.4 (syst)±2.8 (ℬ) pb, where the third uncertainty comes from the uncertainty in the branching fraction of Y(1S) decays to μ+μ−. Assuming instead that the Y(1S) mesons are produced with different polarizations leads to variations in the measured cross section in the range from −38% to +36%.",

keywords = "Hadron-Hadron scattering (experiments), Quarkonium",

author = "{The CMS collaboration} and V. Khachatryan and Sirunyan, {A. M.} and A. Tumasyan and W. Adam and E. Asilar and T. Bergauer and J. Brandstetter and E. Brondolin and M. Dragicevic and J. Er{\"o} and M. Flechl and M. Friedl and R. Fr{\"u}hwirth and Ghete, {V. M.} and C. Hartl and N. H{\"o}rmann and J. Hrubec and M. Jeitler and A. K{\"o}nig and I. Kr{\"a}tschmer and D. Liko and T. Matsushita and I. Mikulec and D. Rabady and N. Rad and B. Rahbaran and H. Rohringer and J. Schieck and J. Strauss and W. Waltenberger and Wulz, {C. E.} and O. Dvornikov and V. Makarenko and V. Zykunov and V. Mossolov and N. Shumeiko and {Suarez Gonzalez}, J. and S. Alderweireldt and {De Wolf}, {E. A.} and X. Janssen and J. Lauwers and {Van De Klundert}, M. and {Van Haevermaet}, H. and {Van Mechelen}, P. and {Van Remortel}, N. and {Van Spilbeeck}, A. and {Abu Zeid}, S. and F. Blekman and J. D{\textquoteright}Hondt and R. Yonamine",

note = "Publisher Copyright: {\textcopyright} 2017, The Author(s).",

year = "2017",

month = may,

day = "1",

doi = "10.1007/JHEP05(2017)013",

language = "English",

volume = "2017",

journal = "Journal of High Energy Physics",

issn = "1126-6708",

publisher = "Springer Verlag",

number = "5",

}