LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2017). Measurement of CP observables in B-+/- -> DK*(+/-) decays using two- and four-body D final states. J. High Energy Phys., 11(11), 156–27pp.
Abstract: Measurements of CP observables in B-+/- -> DK*(+/-) decays are presented, where D denotes a superposition of D-0 and (D) over bar (0) meson states. Decays of the D meson to K-pi(+), K-K+, pi(-)pi(+), K-pi(+)pi(-)pi(+) and pi(-)pi(+)pi(-)pi(+) are used and the K*(+/-) meson is reconstructed in the K-S(0)pi(+/-) final state. This analysis uses a data sample of pp collisions collected with the LHCb experiment, corresponding to integrated luminosities of 1 fb(-1), 2 fb(-1) and 1.8 fb(-1) at centre-of-mass energies root s = 7TeV, 8TeV and 13TeV, respectively. The sensitivity of the results to the CKM angle gamma is discussed.
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LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., et al. (2020). Measurement of CP observables in B+/- -> DK+/- and B+/- -> D pi+/- with D -> KS0 K+/- pi-/+ decays. J. High Energy Phys., 06(6), 058–25pp.
Abstract: Measurements of CP observables in B-+/- -> DK +/- and B-+/- -> D pi (+/-) decays are presented, where D represents a superposition of D-0 and D<overbar>0 states. The D meson is reconstructed in the three-body final states KS0K +/- pi -/+ and KS0K -/+ pi +/-. The analysis uses samples of B mesons produced in proton-proton collisions, corresponding to an integrated luminosity of 1.0, 2.0, and 6.0 fb(-1) collected with the LHCb detector at centre-of-mass energies of <mml:msqrt>s</mml:msqrt> = 7, 8, and 13 TeV, respectively. These measurements are the most precise to date, and provide important input for the determination of the CKM angle gamma.
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LHCb Collaboration(Aaij, R. et al), Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2021). Measurement of CP observables in B-+/- -> D-(*K-)(+/-) and B-+/- -> D-(*())pi(+/-) decays using two-body D final states. J. High Energy Phys., 04(4), 081–36pp.
Abstract: Measurements of CP observables in B-+/- -> D(*) K-+/- and B-+/- -> D(*) pi(+/-) decays are presented, where D(*) indicates a neutral D or D* meson that is an admixture of meson and anti-meson states. Decays of the D(*) meson to the D pi(0) and D gamma final states are partially reconstructed without inclusion of the neutral pion or photon. Decays of the D meson are reconstructed in the K-+/-pi(-/+), K+K-, and pi(+)pi(-) final states. The analysis uses a sample of charged B mesons produced in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb(-1) taken at centre-of-mass energies of 7, 8, and 13TeV, respectively. The measurements of partially reconstructed B-+/- -> D(*) K-+/- and B-+/- -> D(*)pi(+/-) with D -> K--/+pi(+/-) decays are the first of their kind, and a first observation of the B-+/- -> (D pi(0)) D*pi(+/-) decay is made with a significance of 6.1 standard deviations. All CP observables are measured with world-best precision, and in combination with other LHCb results will provide strong constraints on the CKM angle gamma.
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LHCb Collaboration(Aaij, R. et al), Garcia Martin, L. M., Henry, L., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2018). Central exclusive production of J/psi and (2S) mesons in pp collisions at root s=13 TeV. J. High Energy Phys., 10(10), 167–27pp.
Abstract: Measurements are reported of the central exclusive production of J= and ( 2 S) mesons in pp collisions at a centre- of- mass energy of 13 TeV. Backgrounds are signi fi cantly reduced compared to previous measurements made at lower energies through the use of new forward shower counters. The products of the cross- sections and the branching fractions for the decays to dimuons, where both muons are within the pseudorapidity range 2 : 0 < < 4 : 5, are measured to be The fi rst uncertainties are statistical, the second are systematic, and the third are due to the luminosity determination. The cross- sections are also measured di ff erentially for meson rapidities between 2.0 and 4.5. Good agreement is observed with theoretical predictions. Photoproduction cross- sections are derived and compared to previous experiments, and a deviation from a pure power- law extrapolation of lower energy data is observed.
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ATLAS Collaboration(Aaboud, M. et al), Alvarez Piqueras, D., Aparisi Pozo, J. A., Bailey, A. J., Barranco Navarro, L., Cabrera Urban, S., et al. (2019). Searches for third-generation scalar leptoquarks in s=13 TeV pp collisions with the ATLAS detector. J. High Energy Phys., 06(6), 144–48pp.
Abstract: Limits are set on the pair production of scalar leptoquarks, where all possible decays of the leptoquark into a quark (t, b) and a lepton (, ) of the third generation are considered. The limits are presented as a function of the leptoquark mass and the branching ratio into charged leptons for up-type (LQ<sub ) and down-type (/t) leptoquarks. Many results are reinterpretations of previously published ATLAS searches. In all cases, LHC proton-proton collision data at a centre-of-mass energy of = 13 TeV recorded by the ATLAS detector in 2015 and 2016 are used, corresponding to an integrated luminosity of 36.1 fb(-1). Masses below 800 GeV are excluded for both LQu and LQd independently of the branching ratio, with masses below about 1 TeV being excluded for the limiting cases of branching ratios equal to zero or unity.
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