Papers by SERPİL YALÇIN KUZU
Journal of High Energy Physics
Measurements of the production of electrons from heavy-flavour hadron decays in pp collisions at ... more Measurements of the production of electrons from heavy-flavour hadron decays in pp collisions at $$ \sqrt{s} $$ s = 13 TeV at midrapidity with the ALICE detector are presented down to a transverse momentum (pT) of 0.2 GeV/c and up to pT = 35 GeV/c, which is the largest momentum range probed for inclusive electron measurements in ALICE. In p-Pb collisions, the production cross section and the nuclear modification factor of electrons from heavy-flavour hadron decays are measured in the pT range 0.5 < pT< 26 GeV/c at $$ \sqrt{s_{\textrm{NN}}} $$ s NN = 8.16 TeV. The nuclear modification factor is found to be consistent with unity within the statistical and systematic uncertainties. In both collision systems, first measurements of the yields of electrons from heavy-flavour hadron decays in different multiplicity intervals normalised to the multiplicity-integrated yield (self-normalised yield) at midrapidity are reported as a function of the self-normalised charged-particle multipl...
Journal of High Energy Physics
The production of non-prompt D0 mesons from beauty-hadron decays was measured at midrapidity (|y|... more The production of non-prompt D0 mesons from beauty-hadron decays was measured at midrapidity (|y| < 0.5) in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of $$ \sqrt{{\textrm{s}}_{\textrm{NN}}} $$ s NN = 5.02 TeV with the ALICE experiment at the LHC. Their nuclear modification factor (RAA), measured for the first time down to pT = 1 GeV/c in the 0–10% and 30–50% centrality classes, indicates a significant suppression, up to a factor of about three, for pT> 5 GeV/c in the 0–10% central Pb-Pb collisions. The data are described by models that include both collisional and radiative processes in the calculation of beauty-quark energy loss in the quark-gluon plasma, and quark recombination in addition to fragmentation as a hadronisation mechanism. The ratio of the non-prompt to prompt D0-meson RAA is larger than unity for pT> 4 GeV/c in the 0–10% central Pb-Pb collisions, as predicted by models in which beauty quarks lose less energy than charm quarks in the quark-g...
arXiv (Cornell University), Dec 15, 2021
The production of prompt Λ + c baryons at midrapidity (|y| < 0.5) was measured in central (0-10%)... more The production of prompt Λ + c baryons at midrapidity (|y| < 0.5) was measured in central (0-10%) and mid-central (30-50%) Pb-Pb collisions at the center-of-mass energy per nucleon-nucleon pair √ s NN = 5.02 TeV with the ALICE detector. The Λ + c production yield, the Λ + c /D 0 production ratio, and the Λ + c nuclear modification factor R AA are reported. The results are more precise and more differential in transverse momentum (p T) and centrality with respect to previous measurements. The Λ + c /D 0 ratio, which is enhanced with respect to the pp measurement for 4 < p T < 8 GeV/c, is described by theoretical calculations that model the charm-quark transport in the quark-gluon plasma and include hadronization via both coalescence and fragmentation mechanisms.
Journal of High Energy Physics
The production of J/ψ is measured as a function of charged-particle multiplicity at forward rapid... more The production of J/ψ is measured as a function of charged-particle multiplicity at forward rapidity in proton-proton (pp) collisions at center-of-mass energies $$ \sqrt{s} $$ s = 5.02 and 13 TeV. The J/ψ mesons are reconstructed via their decay into dimuons in the rapidity interval (2.5 < y < 4.0), whereas the charged-particle multiplicity density (dNch/dη) is measured at midrapidity (|η| < 1). The production rate as a function of multiplicity is reported as the ratio of the yield in a given multiplicity interval to the multiplicity-integrated one. This observable shows a linear increase with charged-particle multiplicity normalized to the corresponding average value for inelastic events (dNch/dη/〈dNch/dη〉), at both the colliding energies. Measurements are compared with available ALICE results at midrapidity and theoretical model calculations. First measurement of the mean transverse momentum (〈pT〉) of J/ψ in pp collisions exhibits an increasing trend as a function of dNch...
The European Physical Journal C
The multiplicity dependence of jet production in pp collisions at the centre-of-mass energy of $$... more The multiplicity dependence of jet production in pp collisions at the centre-of-mass energy of $$\sqrt{s} = 13\ {\mathrm {TeV}}$$ s = 13 TeV is studied for the first time. Jets are reconstructed from charged particles using the anti-$$k_\mathrm {T}$$ k T algorithm with resolution parameters R varying from 0.2 to 0.7. The jets are measured in the pseudorapidity range $$|\eta _{\mathrm{jet}}|< 0.9-R$$ | η jet | < 0.9 - R and in the transverse momentum range $$5
Physics Letters B, 2022
The first results on K ∗ (892) ± resonance production in inelastic pp collisions at LHC energies o... more The first results on K ∗ (892) ± resonance production in inelastic pp collisions at LHC energies of √ s = 5.02, 8, and 13 TeV are presented. The K ∗ (892) ± has been reconstructed via its hadronic decay channel K ∗ (892) ± → K 0S + π ± with the ALICE detector. Measurements of transverse momentum distributions, p T -integrated yields, and mean transverse momenta for charged K ∗ (892) are found to be consistent with previous ALICE measurements for neutral K ∗ (892) within uncertainties. For p T > 1 GeV/ c the K ∗ (892) ± transverse momentum spectra become harder with increasing centre-of-mass energy from 5.02 to 13 TeV, similar to what previously observed for charged kaons and pions. For p T < 1 GeV/ c the K ∗ (892) ± yield does not evolve significantly and the abundance of K ∗ (892) ± relative to K is rather independent of the collision energy. The transverse momentum spectra, measured for K ∗ (892) ± at midrapidity in the interval 0 < p T < 15 GeV/ c , are not well describ...
Journal of High Energy Physics
Understanding the production mechanism of light (anti)nuclei is one of the key challenges of nucl... more Understanding the production mechanism of light (anti)nuclei is one of the key challenges of nuclear physics and has important consequences for astrophysics, since it provides an input for indirect dark-matter searches in space. In this paper, the latest results about the production of light (anti)nuclei in pp collisions at $$ \sqrt{s} $$ s = 13 TeV are presented, focusing on the comparison with the predictions of coalescence and thermal models. For the first time, the coalescence parameters B2 for deuterons and B3 for helions are compared with parameter-free theoretical predictions that are directly constrained by the femtoscopic measurement of the source radius in the same event class. A fair description of the data with a Gaussian wave function is observed for both deuteron and helion, supporting the coalescence mechanism for the production of light (anti)nuclei in pp collisions. This method paves the way for future investigations of the internal structure of more complex nuclear...
The European Physical Journal C
Angular correlations of heavy-flavour and charged particles in high-energy proton–proton collisio... more Angular correlations of heavy-flavour and charged particles in high-energy proton–proton collisions are sensitive to the production mechanisms of heavy quarks and to their fragmentation as well as hadronisation processes. The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in proton–proton collisions at a centre-of-mass energy of $$\sqrt{s} = 13$$ s = 13 TeV with the ALICE detector is reported, considering $$\mathrm D^{0} $$ D 0 , $$\mathrm D^{+} $$ D + , and $$\mathrm D^{*+} $$ D ∗ + mesons in the transverse-momentum interval $$3< p_{\mathrm{T}} < 36$$ 3 < p T < 36 GeV/$$c$$ c at midrapidity ($$|y| < 0.5$$ | y | < 0.5 ), and charged particles with $$p_{\mathrm{T}} > 0.3$$ p T > 0.3 GeV/$$c$$ c and pseudorapidity $$|\eta | < 0.8$$ | η | < 0.8 . This measurement has an improved precision and provides an extended transverse-momentum coverage compared to previous ALICE measurements at lower energies. The study...
Physics Letters B
The production of prompt D 0 , D + s , and Λ + c hadrons, and their ratios, D + s /D 0 and Λ + c ... more The production of prompt D 0 , D + s , and Λ + c hadrons, and their ratios, D + s /D 0 and Λ + c /D 0 , are measured in proton-proton collisions at √ s = 13 TeV at midrapidity (|y| < 0.5) with the ALICE detector at the LHC. The measurements are performed as a function of the charm-hadron transverse momentum (p T) in intervals of charged-particle multiplicity, measured with two multiplicity estimators covering different pseudorapidity regions. While the strange to non-strange D + s /D 0 ratio indicates no significant multiplicity dependence, the baryon-to-meson p T-differential Λ + c /D 0 ratio shows a multiplicity-dependent enhancement, with a significance of 5.3σ for 1 < p T < 12 GeV/c, comparing the highest multiplicity interval with respect to the lowest one. The measurements are compared with a theoretical model that explains the multiplicity dependence by a canonical treatment of quantum charges in the statistical hadronisation approach, and with predictions from event generators that implement colour reconnection mechanisms beyond the leading colour approximation to model the hadronisation process. The Λ + c /D 0 ratios as a function of p T present a similar shape and magnitude as the Λ/K 0 S ratios in comparable multiplicity intervals, suggesting a potential common mechanism for light-and charm-hadron formation, with analogous multiplicity dependence. The p T-integrated ratios, extrapolated down to p T = 0, do not show a significant dependence on multiplicity within the uncertainties. * See Appendix A for the list of collaboration members Charm-hadron yield ratios versus multiplicity in pp at √ s = 13 TeV ALICE Collaboration
HAL (Le Centre pour la Communication Scientifique Directe), Jul 7, 2021
The production of K * (892) 0 and φ (1020) mesons in proton-proton (pp) and lead-lead (Pb-Pb) col... more The production of K * (892) 0 and φ (1020) mesons in proton-proton (pp) and lead-lead (Pb-Pb) collisions at √ s NN = 5.02 TeV has been measured using the ALICE detector at the Large Hadron Collider (LHC). The transverse momentum (p T) distributions of K * (892) 0 and φ (1020) mesons have been measured at midrapidity (|y| < 0.5) up to p T = 20 GeV/c in inelastic pp collisions and for several Pb-Pb collision centralities. The collision centrality and collision energy dependence of the average transverse momenta agree with the radial flow scenario observed with stable hadrons, showing that the effect is stronger for more central collisions and higher collision energies. The K * 0 /K ratio is found to be suppressed in Pb-Pb collisions relative to pp collisions: this indicates a loss of the measured K * (892) 0 signal due to rescattering of its decay products in the hadronic phase. In contrast, for the longer-lived φ (1020) mesons, no such suppression is observed. The nuclear modification factors (R AA) of K * (892) 0 and φ (1020) mesons are calculated using pp reference spectra at the same collision energy. In central Pb-Pb collisions for p T > 8 GeV/c, the R AA values of K * (892) 0 and φ (1020) are below unity and observed to be similar to those of pions, kaons, and (anti)protons. The R AA values at high p T for K * (892) 0 and φ (1020) mesons are in agreement within uncertainties for √ s NN = 5.02 and 2.76 TeV. * See Appendix A for the list of collaboration members K * (892) 0 and φ (1020) in pp and Pb-Pb collisions at √ s NN = 5.02 TeV ALICE Collaboration K * (892) 0 and φ (1020) in pp and Pb-Pb collisions at √ s NN = 5.02 TeV ALICE Collaboration K * (892) 0 and φ (1020) resonances in Pb-Pb collisions at √ s NN = 5.02 TeV. K * (892) 0 and φ (1020) in pp and Pb-Pb collisions at √ s NN = 5.02 TeV ALICE Collaboration √ s NN = 5.02 TeV ALICE Collaboration K * (892) 0 and φ (1020) in pp and Pb-Pb collisions at √ s NN = 5.02 TeV ALICE Collaboration
HAL (Le Centre pour la Communication Scientifique Directe), May 25, 2021
One of the big challenges for nuclear physics today is to understand, starting from first princip... more One of the big challenges for nuclear physics today is to understand, starting from first principles, the effective interaction between hadrons with different quark content. First successes have been achieved utilizing techniques to solve the dynamics of quarks and gluons on discrete space-time lattices. Experimentally, the dynamics of the strong interaction have been studied by scattering hadrons off each other. Such scattering experiments are difficult or impossible for unstable hadrons and hence, high quality measurements exist only for hadrons containing up and down quarks. In this work, we demonstrate that measuring correlations in the momentum space between hadron pairs produced in ultrarelativistic proton--proton collisions at the CERN LHC provides a precise method to obtain the missing information on the interaction dynamics between any pair of unstable hadrons. Specifically, we discuss the case of the interaction of baryons containing strange quarks (hyperons). We demonstra...
Physical Review Letters, 2021
Physical Review Letters, 2021
The European Physical Journal C, 2020
The measurement of the azimuthal-correlation function of prompt D mesons with charged particles i... more The measurement of the azimuthal-correlation function of prompt D mesons with charged particles in pp collisions at $$\sqrt{s} =5.02\ \hbox {TeV}$$ s = 5.02 TeV and p–Pb collisions at $$\sqrt{s_{\mathrm{NN}}} = 5.02\ \hbox {TeV}$$ s NN = 5.02 TeV with the ALICE detector at the LHC is reported. The $$\mathrm{D}^{0}$$ D 0 , $$\mathrm{D}^{+} $$ D + , and $$\mathrm{D}^{*+} $$ D ∗ + mesons, together with their charge conjugates, were reconstructed at midrapidity in the transverse momentum interval $$3< p_\mathrm{T} < 24\ \hbox {GeV}/c$$ 3 < p T < 24 GeV / c and correlated with charged particles having $$p_\mathrm{T} > 0.3\ \hbox {GeV}/c$$ p T > 0.3 GeV / c and pseudorapidity $$|\eta | < 0.8$$ | η | < 0.8 . The properties of the correlation peaks appearing in the near- and away-side regions (for $$\Delta \varphi \approx 0$$ Δ φ ≈ 0 and $$\Delta \varphi \approx \pi $$ Δ φ ≈ π , respectively) were extracted via a fit to the azimuthal correlation functions. The shape ...
Physics Letters B, 2021
In quantum scattering processes between two particles, aspects characterizing the strong and Coul... more In quantum scattering processes between two particles, aspects characterizing the strong and Coulomb forces can be observed in kinematic distributions of the particle pairs. The sensitivity to the interaction potential reaches a maximum at low relative momentum and vanishing distance between the two particles. Ultrarelativistic heavy-ion collisions at the LHC provide an abundant source of many hadron species and can be employed as a measurement method of scattering parameters that is complementary to scattering experiments. This study confirms that momentum correlations of particles produced in Pb-Pb collisions at the LHC provide an accurate measurement of kaon-proton scattering parameters at low relative momentum, allowing precise access to the K − p → K − p process. This work also validates the femtoscopic measurement in ultrarelativistic heavy-ion collisions as an alternative to scattering experiments and a complementary tool to the study of exotic atoms with comparable precision. In this work, the first femtoscopic measurement of momentum correlations of K − p (K + p) and K + p (K − p) pairs in Pb-Pb collisions at centre-of-mass energy per nucleon pair of √ s NN = 5.02 TeV registered by the ALICE experiment is reported. The components of the K − p complex scattering length are extracted and found to be f 0 = −0.91 ± 0.03(stat) +0.17 −0.03 (syst) and f 0 = 0.92 ± 0.05(stat) +0.12 −0.33 (syst). The results are compared with chiral effective field theory predictions as well as with existing data from dedicated scattering and exotic kaonic atom experiments.
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Papers by SERPİL YALÇIN KUZU