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1. Measurement of J/ψ production cross-sections in pp collisions at $$ \sqrt{s} $$ = 5 TeV

   https://doi.org/10.1007/JHEP11(2021)181  

   Aaij, R. ; Abdelmotteleb, A. S. ; Abellán Beteta, C. ; Ackernley, T. ; Adeva, B. ; Adinolfi, M. ; Afsharnia, H. ; Agapopoulou, C. ; Aidala, C. A. ; Aiola, S. ; et al ( November 2021 , Journal of High Energy Physics)

   A bstract The production cross-sections of J/ψ mesons in proton-proton collisions at a centre-of-mass energy of $$ \sqrt{s} $$ s = 5 TeV are measured using a data sample corresponding to an integrated luminosity of 9 . 13 ± 0 . 18 pb − 1 , collected by the LHCb experiment. The cross-sections are measured differentially as a function of transverse momentum, p T , and rapidity, y , and separately for J/ψ mesons produced promptly and from beauty hadron decays (nonprompt). With the assumption of unpolarised J/ψ mesons, the production cross-sections integrated over the kinematic range 0 < p T < 20 GeV/ c and 2 . 0 < y < 4 . 5 are $$ {\displaystyle \begin{array}{c}{\sigma}_{\mathrm{prompt}}\ J/\psi =8.154\pm 0.010\pm 0.283\ \upmu \mathrm{b},\\ {}{\sigma}_{\mathrm{nonprompt}}\ J/\psi =0.820\pm 0.003\pm 0.034\ \upmu \mathrm{b},\end{array}} $$ σ prompt J / ψ = 8.154 ± 0.010 ± 0.283 μb , σ nonprompt J / ψ = 0.820 ± 0.003 ± 0.034 μb , where the first uncertainties are statistical and the second systematic. These cross-sections are compared with those at $$ \sqrt{s} $$ s = 8 TeV and 13 TeV, and are used to update the measurement of the nuclear modification factor in proton-lead collisions for J/ψ mesons at a centre-of-mass energy per nucleon pair of $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 5 TeV. The results are compared with theoretical predictions. 

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2. J/ψ production at midrapidity in p-Pb collisions at $$ \sqrt{s_{\textrm{NN}}} $$ = 8.16 TeV

   https://doi.org/10.1007/JHEP07(2023)137  

   Acharya, S. ; Adamová, D. ; Adler, A. ; Aglieri Rinella, G. ; Agnello, M. ; Agrawal, N. ; Ahammed, Z. ; Ahmad, S. ; Ahn, S. U. ; Ahuja, I. ; et al ( July 2023 , Journal of High Energy Physics)

   The production of inclusive, prompt and non-prompt J/ψwas studied for the first time at midrapidity (−1.37< y_cms<0.43) in p-Pb collisions at$$ \sqrt{s_{\textrm{NN}}} $$$\sqrt{s_{\mathrm{NN}}}$= 8.16 TeV with the ALICE detector at the LHC. The inclusive J/ψmesons were reconstructed in the dielectron decay channel in the transverse momentum (p_T) interval 0< p_T<14 GeV/cand the prompt and non-prompt contributions were separated on a statistical basis forp_T>2 GeV/c. The study of the J/ψmesons in the dielectron channel used for the first time in ALICE online single-electron triggers from the Transition Radiation Detector, providing a data sample corresponding to an integrated luminosity of 689 ± 13μb⁻¹. The proton-proton reference cross section for inclusive J/ψwas obtained based on interpolations of measured data at different centre-of-mass energies and a universal function describing thep_T-differential J/ψproduction cross sections. Thep_T-differential nuclear modification factorsR_pPbof inclusive, prompt, and non-prompt J/ψare consistent with unity and described by theoretical models implementing only nuclear shadowing.

    

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3. Inclusive, prompt and non-prompt J/ψ production at midrapidity in p-Pb collisions at $$ \sqrt{s_{\mathrm{NN}}} $$ = 5.02 TeV

   https://doi.org/10.1007/JHEP06(2022)011  

   Acharya, S. ; Adamová, D. ; Adler, A. ; Adolfsson, J. ; Aglieri Rinella, G. ; Agnello, M. ; Agrawal, N. ; Ahammed, Z. ; Ahmad, S. ; Ahn, S. U. ; et al ( June 2022 , Journal of High Energy Physics)

   A bstract A measurement of inclusive, prompt, and non-prompt J/ ψ production in p-Pb collisions at a nucleon-nucleon centre-of-mass energy $$ \sqrt{s_{\mathrm{NN}}} $$ s NN = 5 . 02 TeV is presented. The inclusive J/ ψ mesons are reconstructed in the dielectron decay channel at midrapidity down to a transverse momentum p T = 0. The inclusive J/ ψ nuclear modification factor R pPb is calculated by comparing the new results in p-Pb collisions to a recently measured proton-proton reference at the same centre-of-mass energy. Non-prompt J/ ψ mesons, which originate from the decay of beauty hadrons, are separated from promptly produced J/ ψ on a statistical basis for p T larger than 1.0 GeV/ c . These results are based on the data sample collected by the ALICE detector during the 2016 LHC p-Pb run, corresponding to an integrated luminosity $$ \mathcal{L} $$ L int = 292 ± 11 μ b − 1 , which is six times larger than the previous publications. The total uncertainty on the p T -integrated inclusive J/ ψ and non-prompt J/ ψ cross section are reduced by a factor 1.7 and 2.2, respectively. The measured cross sections and R pPb are compared with theoretical models that include various combinations of cold nuclear matter effects. From the non-prompt J/ ψ production cross section, the $$ \mathrm{b}\overline{\mathrm{b}} $$ b b ¯ production cross section at midrapidity, $$ {\mathrm{d}\sigma}_{\mathrm{b}\overline{\mathrm{b}}} $$ d σ b b ¯ / d y , and the total cross section extrapolated over full phase space, $$ {\sigma}_{\mathrm{b}\overline{\mathrm{b}}} $$ σ b b ¯ , are derived. 

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4. Inclusive quarkonium production in pp collisions at $$\sqrt{s}$$ = 5.02 TeV

   https://doi.org/10.1140/epjc/s10052-022-10896-8  

   Acharya, S. ; Adamová, D. ; Adler, A. ; Adolfsson, J. ; Aglieri Rinella, G. ; Agnello, M. ; Agrawal, N. ; Ahammed, Z. ; Ahmad, S. ; Ahn, S. U. ; et al ( January 2023 , The European Physical Journal C)

   Abstract This article reports on the inclusive production cross section of several quarkonium states, $$\textrm{J}/\psi $$ J / ψ , $$\psi \mathrm{(2S)}$$ ψ ( 2 S ) , $$\Upsilon \mathrm (1S)$$ Υ ( 1 S ) , $$\Upsilon \mathrm{(2S)}$$ Υ ( 2 S ) , and $$\Upsilon \mathrm{(3S)}$$ Υ ( 3 S ) , measured with the ALICE detector at the LHC, in pp collisions at $$\sqrt{s} = 5.02$$ s = 5.02  TeV. The analysis is performed in the dimuon decay channel at forward rapidity ( $$2.5< y < 4$$ 2.5 < y < 4 ). The integrated cross sections and transverse-momentum ( $$p_{\textrm{T}}$$ p T ) and rapidity ( $$y$$ y ) differential cross sections for $$\textrm{J}/\psi $$ J / ψ , $$\psi \mathrm{(2S)}$$ ψ ( 2 S ) , $$\Upsilon \mathrm (1S)$$ Υ ( 1 S ) , and the $$\psi \mathrm{(2S)}$$ ψ ( 2 S ) -to- $$\textrm{J}/\psi $$ J / ψ cross section ratios are presented. The integrated cross sections, assuming unpolarized quarkonia, are: $$\sigma _{\textrm{J}/\psi }$$ σ J / ψ  ( $$p_{\textrm{T}} <20$$ p T < 20  GeV/c) = 5.88 ± 0.03 ± 0.34 $$ ~\mu $$ μ b, $$\sigma _{\psi \mathrm{(2S)}}$$ σ ψ ( 2 S )  ( $$p_{\textrm{T}} <12$$ p T < 12  GeV/c) = 0.87 ± 0.06 ± 0.10 $$~\mu $$ μ b, $$\sigma _{\Upsilon \mathrm (1S)}$$ σ Υ ( 1 S )  ( $$p_{\textrm{T}} <15$$ p T < 15  GeV/c) = 45.5 ± 3.9 ± 3.5 nb, $$\sigma _{\Upsilon \mathrm{(2S)}}$$ σ Υ ( 2 S )  ( $$p_{\textrm{T}} <15$$ p T < 15  GeV/c) = 22.4 ± 3.2 ± 2.7 nb, and $$\sigma _{\Upsilon \mathrm{(3S)}}$$ σ Υ ( 3 S )  ( $$p_{\textrm{T}} <15$$ p T < 15  GeV/c) = 4.9 ± 2.2 ± 1.0 nb, where the first (second) uncertainty is the statistical (systematic) one. For the first time, the cross sections of the three $$\Upsilon $$ Υ states, as well as the $$\psi \mathrm{(2S)}$$ ψ ( 2 S ) one as a function of $$p_{\textrm{T}}$$ p T and $$y$$ y , are measured at $$\sqrt{s} = 5.02$$ s = 5.02  TeV at forward rapidity. These measurements also significantly extend the $$\textrm{J}/\psi $$ J / ψ $$p_{\textrm{T}}$$ p T reach and supersede previously published results. A comparison with ALICE measurements in pp collisions at $$\sqrt{s} = 2.76$$ s = 2.76 , 7, 8, and 13 TeV is presented and the energy dependence of quarkonium production cross sections is discussed. Finally, the results are compared with the predictions from several production models. 

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5. Measurement of beauty and charm production in pp collisions at $$ \sqrt{s} $$ = 5.02 TeV via non-prompt and prompt D mesons

   https://doi.org/10.1007/JHEP05(2021)220  

   Acharya, S. ; Adamová, D. ; Adler, A. ; Adolfsson, J. ; Aglieri Rinella, G. ; Agnello, M. ; Agrawal, N. ; Ahammed, Z. ; Ahmad, S. ; Ahn, S. U. ; et al ( May 2021 , Journal of High Energy Physics)

   null (Ed.)

   A bstract The p T -differential production cross sections of prompt and non-prompt (produced in beauty-hadron decays) D mesons were measured by the ALICE experiment at midrapidity ( | y | < 0 . 5) in proton-proton collisions at $$ \sqrt{s} $$ s = 5 . 02 TeV. The data sample used in the analysis corresponds to an integrated luminosity of (19 . 3 ± 0 . 4) nb − 1 . D mesons were reconstructed from their decays D 0 → K − π + , D + → K − π + π + , and $$ {\mathrm{D}}_{\mathrm{s}}^{+}\to \upphi {\uppi}^{+}\to {\mathrm{K}}^{-}{\mathrm{K}}^{+}{\uppi}^{+} $$ D s + → ϕ π + → K − K + π + and their charge conjugates. Compared to previous measurements in the same rapidity region, the cross sections of prompt D + and $$ {\mathrm{D}}_{\mathrm{s}}^{+} $$ D s + mesons have an extended p T coverage and total uncertainties reduced by a factor ranging from 1.05 to 1.6, depending on p T , allowing for a more precise determination of their p T -integrated cross sections. The results are well described by perturbative QCD calculations. The fragmentation fraction of heavy quarks to strange mesons divided by the one to non-strange mesons, f s / ( f u + f d ), is compatible for charm and beauty quarks and with previous measurements at different centre-of-mass energies and collision systems. The $$ \mathrm{b}\overline{\mathrm{b}} $$ b b ¯ production cross section per rapidity unit at midrapidity, estimated from non-prompt D-meson measurements, is $$ \mathrm{d}{\sigma}_{\mathrm{b}\overline{\mathrm{b}}}/\mathrm{d}y\left|{}_{\left|\mathrm{y}\right|<0.5}=34.5\pm 2.4{\left(\mathrm{stat}\right)}_{-2.9}^{+4.7}\left(\mathrm{tot}.\mathrm{syst}\right)\right. $$ d σ b b ¯ / d y y < 0.5 = 34.5 ± 2.4 stat − 2.9 + 4.7 tot . syst μb. It is compatible with previous measurements at the same centre-of-mass energy and with the cross section pre- dicted by perturbative QCD calculations. 

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