28 research outputs found
Hypertriton Production in p-Pb Collisions at âsNN = 5.02 TeV
The study of nuclei and antinuclei production has proven to be a powerful
tool to investigate the formation mechanism of loosely bound states in
high-energy hadronic collisions. The first measurement of the production of
in p-Pb collisions at = 5.02
TeV is presented in this Letter. Its production yield measured in the rapidity
interval -1 < y < 0 for the 40% highest multiplicity p-Pb collisions is . The measurement is compared with the expectations of statistical
hadronisation and coalescence models, which describe the nucleosynthesis in
hadronic collisions. These two models predict very different yields of the
hypertriton in small collision systems such as p-Pb and therefore the
measurement of is crucial to distinguish between them.
The precision of this measurement leads to the exclusion with a significance
larger than 6 of some configurations of the statistical hadronisation,
thus constraining the production mechanism of loosely bound states
Measurement of the non-prompt D-meson fraction as a function of multiplicity in proton-proton collisions at = 13 TeV
The fractions of non-prompt (i.e. originating from beauty-hadron decays) D0
and D+ mesons with respect to the inclusive yield are measured as a function of the
charged-particle multiplicity in proton-proton collisions at a centre-of-mass energy of âs =
13 TeV with the ALICE detector at the LHC. The results are reported in intervals of
transverse momentum (pT) and integrated in the range 1 < pT < 24 GeV/c. The fraction
of non-prompt D0 and D+ mesons is found to increase slightly as a function of pT in
all the measured multiplicity intervals, while no significant dependence on the charged-
particle multiplicity is observed. In order to investigate the production and hadronisation
mechanisms of charm and beauty quarks, the results are compared to PYTHIA 8 as well
as EPOS 3 and EPOS 4 Monte Carlo simulations, and to calculations based on the colour
glass condensate including three-pomeron fusion
General balance functions of identified charged hadron pairs of (pi,K,p) in Pb-Pb collisions at 2.76 TeV
First measurements of balance functions (BFs) of all combinations of identified charged hadron ( Ï , K, p)
pairs in PbâPb collisions at âsNN = 2.76 TeV recorded by the ALICE detector are presented. The BF
measurements are carried out as two-dimensional differential correlators versus the relative rapidity
(delta-y) and azimuthal angle (delta-Ï) of hadron pairs, and studied as a function of collision centrality. The delta-Ï
dependence of BFs is expected to be sensitive to the light quark diffusivity in the quarkâgluon plasma.
While the BF azimuthal widths of all pairs substantially decrease from peripheral to central collisions, the
longitudinal widths exhibit mixed behaviors: BFs of Ï Ï and cross-species pairs narrow significantly in
more central collisions, whereas those of KK and pp are found to be independent of collision centrality.
This dichotomy is qualitatively consistent with the presence of strong radial flow effects and the existence
of two stages of quark production in relativistic heavy-ion collisions. Finally, the first measurements of
the collision centrality evolution of BF integrals are presented, with the observation that charge balancing
fractions are nearly independent of collision centrality in PbâPb collisions. Overall, the results presented
provide new and challenging constraints for theoretical models of hadron production and transport in
relativistic heavy-ion collisions
Application of fuzzy consensus for oral pre-cancer and cancer susceptibility assessment
Health questionnaire data assessment conventionally relies upon statistical analysis in understanding disease susceptibility using discrete numbers and fails to reflect physicianâs perspectives and missing narratives in data, which play subtle roles in disease prediction. In addressing such limitations, the present study applies fuzzy consensus in oral health and habit questionnaire data for a selected Indian population in the context of assessing susceptibility to oral pre-cancer and cancer. Methodically collected data were initially divided into age based small subgroups and fuzzy membership function was assigned to each. The methodology further proposed the susceptibility to oral precancers (viz. leukoplakia, oral submucous fibrosis) and squamous cell carcinoma in patients considering a fuzzy rulebase through If-Then rules with certain conditions. Incorporation of similarity measures using the Jaccard index was used during conversion into the linguistic output of fuzzy set to predict the disease outcome in a more accurate manner and associated condition of the relevant features. It is also expected that this analytical approach will be effective in devising strategies for policy making through real-life questionnaire data handling
Multiplicity dependence of light-flavor hadron production in pp collisions at s =7 TeV
Comprehensive results on the production of unidentified charged particles, ϱ, K±, KS0, Kâ(892)0, p, p, Ï(1020), Î, Î, Î-, Î+, Ω-, and Ω+ hadrons in proton-proton (pp) collisions at s=7 TeV at midrapidity (|y|<0.5) as a function of charged-particle multiplicity density are presented. In order to avoid autocorrelation biases, the actual transverse momentum (pT) spectra of the particles under study and the event activity are measured in different rapidity windows. In the highest multiplicity class, the charged-particle density reaches about 3.5 times the value measured in inelastic collisions. While the yield of protons normalized to pions remains approximately constant as a function of multiplicity, the corresponding ratios of strange hadrons to pions show a significant enhancement that increases with increasing strangeness content. Furthermore, all identified particle-to-pion ratios are shown to depend solely on charged-particle multiplicity density, regardless of system type and collision energy. The evolution of the spectral shapes with multiplicity and hadron mass shows patterns that are similar to those observed in p-Pb and Pb-Pb collisions at Large Hadron Collider energies. The obtained pT distributions and yields are compared to expectations from QCD-based pp event generators as well as to predictions from thermal and hydrodynamic models. These comparisons indicate that traces of a collective, equilibrated system are already present in high-multiplicity pp collisions