TY - JOUR
T1 - Observation of proton-tagged, central (semi)exclusive production of high-mass lepton pairs in pp collisions at 13 TeV with the CMS-TOTEM precision proton spectrometer
AU - The CMS collaboration
AU - The TOTEM collaboration
AU - Sirunyan, A. M.
AU - Tumasyan, A.
AU - Adam, W.
AU - Ambrogi, F.
AU - Asilar, E.
AU - Bergauer, T.
AU - Brandstetter, J.
AU - Brondolin, E.
AU - Dragicevic, M.
AU - Erö, J.
AU - Escalante Del Valle, A.
AU - Flechl, M.
AU - Friedl, M.
AU - Frühwirth, R.
AU - Ghete, V. M.
AU - Grossmann, J.
AU - Hrubec, J.
AU - Jeitler, M.
AU - König, A.
AU - Krammer, N.
AU - Krätschmer, I.
AU - Liko, D.
AU - Madlener, T.
AU - Mikulec, I.
AU - Pree, E.
AU - Rad, N.
AU - Rohringer, H.
AU - Schieck, J.
AU - Schöfbeck, R.
AU - Spanring, M.
AU - Spitzbart, D.
AU - Taurok, A.
AU - Waltenberger, W.
AU - Wittmann, J.
AU - Wulz, C. E.
AU - Zarucki, M.
AU - Chekhovsky, V.
AU - Mossolov, V.
AU - Suarez Gonzalez, J.
AU - De Wolf, E. A.
AU - Di Croce, D.
AU - Janssen, X.
AU - Lauwers, J.
AU - Pieters, M.
AU - Van De Klundert, M.
AU - Van Haevermaet, H.
AU - Van Mechelen, P.
AU - Van Remortel, N.
AU - Abu Zeid, S.
AU - Moraes, A.
N1 - Publisher Copyright:
© 2018, The Author(s).
PY - 2018/7/1
Y1 - 2018/7/1
N2 - The process pp → pℓ+ℓ−p(*), with ℓ+ℓ− a muon or an electron pair produced at midrapidity with mass larger than 110 GeV, has been observed for the first time at the LHC in pp collisions at s=13 TeV. One of the two scattered protons is measured in the CMS-TOTEM precision proton spectrometer (CT-PPS), which operated for the first time in 2016. The second proton either remains intact or is excited and then dissociates into a low-mass state p*, which is undetected. The measurement is based on an integrated luminosity of 9.4 fb−1 collected during standard, high-luminosity LHC operation. A total of 12 μ+μ− and 8 e+e− pairs with m(ℓ+ℓ−) > 110 GeV, and matching forward proton kinematics, are observed, with expected backgrounds of 1.49 ± 0.07 (stat) ± 0.53 (syst) and 2.36 ± 0.09 (stat) ± 0.47 (syst), respectively. This corresponds to an excess of more than five standard deviations over the expected background. The present result constitutes the first observation of proton-tagged γγ collisions at the electroweak scale. This measurement also demonstrates that CT-PPS performs according to the design specifications.[Figure not available: see fulltext.].
AB - The process pp → pℓ+ℓ−p(*), with ℓ+ℓ− a muon or an electron pair produced at midrapidity with mass larger than 110 GeV, has been observed for the first time at the LHC in pp collisions at s=13 TeV. One of the two scattered protons is measured in the CMS-TOTEM precision proton spectrometer (CT-PPS), which operated for the first time in 2016. The second proton either remains intact or is excited and then dissociates into a low-mass state p*, which is undetected. The measurement is based on an integrated luminosity of 9.4 fb−1 collected during standard, high-luminosity LHC operation. A total of 12 μ+μ− and 8 e+e− pairs with m(ℓ+ℓ−) > 110 GeV, and matching forward proton kinematics, are observed, with expected backgrounds of 1.49 ± 0.07 (stat) ± 0.53 (syst) and 2.36 ± 0.09 (stat) ± 0.47 (syst), respectively. This corresponds to an excess of more than five standard deviations over the expected background. The present result constitutes the first observation of proton-tagged γγ collisions at the electroweak scale. This measurement also demonstrates that CT-PPS performs according to the design specifications.[Figure not available: see fulltext.].
KW - Forward physics
KW - Hadron-Hadron scattering (experiments)
KW - Photon production
KW - proton-proton scattering
UR - http://www.scopus.com/inward/record.url?scp=85051832717&partnerID=8YFLogxK
U2 - 10.1007/JHEP07(2018)153
DO - 10.1007/JHEP07(2018)153
M3 - Article
AN - SCOPUS:85051832717
SN - 1029-8479
VL - 2018
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
IS - 7
M1 - 153
ER -