Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages

First measurement of the C P -violating phase in B s 0 → J / ψ ( → e + e - ) ϕ decays

Abstract: A flavour-tagged time-dependent angular analysis of Bs0→J/ψϕ decays is presented where the J/ψ meson is reconstructed through its decay to an e+e- pair. The analysis uses a sample of pp collision data recorded with the LHCb experiment at centre-of-mass energies of 7 and 8\,Te V, corresponding to an integrated luminosity of 3\,fb-1. The CP-violating phase and lifetime parameters of the Bs0 system are measured to be ϕs=0.00±0.28±0.07\,rad, ΔΓs=0.115±0.045±0.011\,ps-1 and Γs=0.608±0.018±0.012\,ps-1 where the first uncertainty is statistical and the second systematic. This is the first time that CP-violating parameters are measured in the Bs0→J/ψϕ decay with an e+e- pair in the final state. The results are consistent with previous measurements in other channels and with the Standard Model predictions

Search for the doubly charmed baryon Ω cc +

Abstract: A search for the doubly charmed baryon Ωcc+ with the decay mode Ωcc+ → Ξc+K−π+ is performed using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the LHCb experiment from 2016 to 2018, corresponding to an integrated luminosity of 5.4 fb−1. No significant signal is observed within the invariant mass range of 3.6 to 4.0GeV/c2. Upper limits are set on the ratio R of the production cross-section times the total branching fraction of the Ωcc+ → Ξc+K−π+ decay with respect to the Ξcc++→Λc+K−π+π+ decay. Upper limits at 95% credibility level for R in the range 0.005 to 0.11 are obtained for different hypotheses on the Ωcc+ mass and lifetime in the rapidity range from 2.0 to 4.5 and transverse momentum range from 4 to 15 GeV/c

Use of small-amplitude oscillatory shear rheometry to study the flow properties of pure and potassium-doped Li2ZrO3 sorbents during the sorption of CO2 at high temperatures

Background: Experience and research indicates that there exist a communication gap between research and industry in software engineering. Objective: We propose the Software Engineering Research and Practice (SERP) taxonomy architecture to support communication between practitioners and researchers. The taxonomy architecture provides a basis for classifying research from a problem perspective which in turn supports the breaking down of complex practical challenges to researchable units. Thus such taxonomy may support the mapping of challenges in industry to research solutions in the software engineering context. Method: In this paper we present SERP and exemplifies its usage based on two literature studies in the field of software engineering. Further, we discuss how a taxonomy based on this architecture could have helped us in two past research projects that were conducted in close collaboration with industry. Finally we validate SERP by applying it to the area of software testing, developing SERP-test, and interviewing two industry practitioners and two researchers. Results: The taxonomy architecture has been applied to two problems in software testing, and has been assessed through interviews with practitioners and researchers. The interviews provided suggestions of how to improve the taxonomy architecture, which have been incorporated. With two examples, we demonstrated how the taxonomy architecture could be used to find solutions for industrial problems, and to find the problems addressed by a particular solution. Conclusion: SERP may be useful in multiple ways: (1) Given that SERP taxonomies are populated with industrial problems and scientific solutions, we could rapidly identify candidate research solutions for industrial practice. (2) Researchers could benefit from the taxonomy in the reporting of their research to ease the mapping to industrial challenges

Influence of texture in hybrid carbon-phosphomolybdic acid materials on their performance as electrodes in supercapacitors

In this paper, phosphomolybdic acid H3PMo12O40 (PMo12) was anchored to four synthetic micro-mesoporous carbons and a commercial one to analyse the relationship between the porous texture of the support, the PMo12 adsorption and the performance of the resulting hybrid materials as electrodes in supercapacitors. The uptake of PMo12 on carbon supports follows a clear correlation with the micropore volume, which implies that PMo12 is mainly adsorbed in microporosity as a consequence of a greater confinement in this kind of pores instead of mesopores. Transmission electron microscopy indicates that the PMo12 adsorbed is homogeneously dispersed in the carbon texture. Finally, the addition of PMo12 to the original carbon electrodes provided capacitances up to 293 F per gram of electrode, substantially larger than the 206–240 F g−1 of the unmodified activated carbon. This result represented an increase of up to 35% in terms of gravimetric energy density and 160% in terms of volumetric energy density, after PMo12 integration into the carbon matrix