We have used polarized neutron reflectometry to show that controlled variation of growth pressure during deposition of Co/Pd multilayers can be used to achieve a significant vertical gradient in the effective anisotropy. This gradient is strongly dependent on deposition order (low to high pressure or vice versa), and is accompanied by a corresponding gradient in saturation magnetization. These results demonstrate pressure-grading as an attractively simple technique for tailoring the anisotropy profile of magnetic media.

The first measurement of the Z boson production cross-section at centre-of-mass energy s = 5.02 TeV in the forward region is reported, using pp collision data collected by the LHCb experiment in year 2017, corresponding to an integrated luminosity of 100 ± 2 pb−1. The production cross-section is measured for final-state muons in the pseudorapidity range 2.0 < η < 4.5 with transverse momentum pT> 20 GeV/c. The integrated cross-section is determined to be (Formula presented.) for the di-muon invariant mass in the range 60 < Mμμ< 120 GeV/c2. This result and the differential cross-section results are in good agreement with theoretical predictions at next-to-next-to-leading order in the strong coupling constant. Based on a previous LHCb measurement of the Z boson production cross-section in pPb collisions at sNN = 5.02 TeV, the nuclear modification factor RpPb is measured for the first time at this energy. The measured values are 1.2−0.3+0.5 (stat) ± 0.1(syst) in the forward region (1.53

The production of prompt D + and Ds+ mesons is studied in proton-lead collisions at a centre-of-mass energy of sNN = 5.02 TeV. The data sample corresponding to an integrated luminosity of (1.58 ± 0.02)nb −1 is collected by the LHCb experiment at the LHC. The differential production cross-sections are measured using D + and Ds+ candidates with transverse momentum in the range of 0 < p T < 14 GeV/c and rapidities in the ranges of 1.5 < y ∗ < 4.0 and –5.0 < y ∗ < –2.5 in the nucleon-nucleon centre-of-mass system. For both particles, the nuclear modification factor and the forward-backward production ratio are determined. These results are compared with theoretical models that include initial-state nuclear effects. In addition, measurements of the cross-section ratios between D +, Ds+ and D 0 mesons are presented, providing a baseline for studying the charm hadronization in lead-lead collisions at LHC energies. [Figure not available: see fulltext.].

A model-independent study of CP violation in B0→DK∗0 decays is presented using data corresponding to an integrated luminosity of 9\,fb-1 collected by the LHCb experiment at centre-of-mass energies of s=7,8 and 13\,TeV. The CKM angle γ is determined by examining the distributions of signal decays in phase-space bins of the self-conjugate D→KS0h+h- decays, where h=π,K. Observables related to CP violation are measured and the angle γ is determined to be γ=(49-19+22)∘. Measurements of the amplitude ratio and strong-phase difference between the favoured and suppressed B0 decays are also presented.