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Expanding the synergy between MOFs and solid-state nanochannels: robust anchoring of enzymes for iontronic biosensing
No full textSearch for near-threshold multi-neutron resonances with (p,2p) reactions in neutron-rich nuclei at R3B
No full textMultiplicity dependence of ϒ production at forward rapidity in pp collisions at = 13 TeV
No full textThe measurement of ϒ(1S), ϒ(2S), and ϒ(3S) yields as a function of the charged-particle multiplicity density, dNch/dη, using the ALICE experiment at the LHC, is reported in pp collisions at = 13 TeV. The ϒ meson yields are measured at forward rapidity (2.5 < y<4) in the dimuon decay channel, whereas the charged-particle multiplicity is defined at central rapidity (|η|<1). Both quantities are divided by their average value in minimum bias events to compute the self-normalized quantities. The increase of the self-normalized ϒ(1S), ϒ(2S), and ϒ(3S) yields is found to be compatible with a linear scaling with the self-normalized dN/dη, within the uncertainties. The self-normalized yield ratios of excited-to-ground ϒ states are compatible with unity within uncertainties. Similarly, the measured double ratio of the self-normalized ϒ(1S) to the self-normalized J/ψ yields, both measured at forward rapidity, is compatible with unity for self-normalized charged-particle multiplicities beyond one. The measurements are compared with theoretical predictions incorporating initial or final state effects
Light neutral-meson production in pp collisions at = 13 TeV
No full textThe momentum-differential invariant cross sections of π and η mesons are reported for pp collisions at = 13 TeV at midrapidity (|y| < 0.8). The measurement is performed in a broad transverse-momentum range of 0.2 < p< 200 GeV/c and 0.4 < p< 60 GeV/c for the π and η, respectively, extending the p coverage of previous measurements. Transverse-mass-scaling violation of up to 60% at low transverse momentum has been observed, agreeing with measurements at lower collision energies. Transverse Bjorken x (x) scaling of the π cross sections at LHC energies is fulfilled with a power-law exponent of n = 5.01 ± 0.05, consistent with values obtained for charged pions at similar collision energies. The data are compared to predictions from next-to-leading order perturbative QCD calculations, where the π spectrum is best described using the CT18 parton distribution function and the NNFF1.0 or BDSS fragmentation function. Expectations from PYTHIA8 and EPOS LHC overestimate the spectrum for the π and are not able to describe the shape and magnitude of the η spectrum. The charged-particle multiplicity dependent π and η p spectra show the expected change of the spectral shape, characterized by a flatter slope with increasing multiplicity. This is demonstrated across a broad transverse-momentum range and up to events with a charged-particle multiplicity exceeding five times the mean value in minimum bias collisions. The η/π ratio depends on the charged-particle multiplicity for p< 4 GeV/c. PYTHIA8 and EPOS LHC qualitatively explain this behavior with an increasing contribution from the feed-down of heavier particles to the π spectrum
Investigating the and dynamics with femtoscopy in pp collisions at TeV
No full textThe interaction between pions and nucleons plays a crucial role in hadron physics. It represents a fundamental building block of the low-energy QCD dynamics and is subject to several resonance excitations. This work studies the dynamics using femtoscopic correlations in high-multiplicity pp collisions at TeV measured by ALICE at the LHC. As the final-state interaction between protons and pions is well constrained by scattering experiments and the study of pionic hydrogen, the results give access to information on the particle-emitting source in pp collisions using the femtoscopy methods. The scaling of the source size of primordial protons and pions against their pair transverse mass is extracted. The results are compared with the source sizes studied with p–p, , and – pairs by ALICE in the same collision system and are found to be in agreement for the different particle pairs. This reinforces recent findings by ALICE of a common emission source for all hadron-pairs in pp collisions at LHC energies. Furthermore, the systems are studied using three-particle femtoscopy in pp collisions at TeV. The presence of three-body effects is analyzed utilizing the cumulant expansion method. In this formalism, the known two-body interactions are subtracted in order to isolate the three-body effects. For both, and , a non-zero cumulant is found, indicating effects beyond pairwise interactions. These results give information on the coupling of the pion to multiple nucleons
Investigating the p- and p-p- dynamics with femtoscopy in pp collisions at TeV
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