Microcanonical Jet-fragmentation in proton-proton collisions at LHC Energy

In this paper, we show that the distribution of the longitudinal momentum fraction of charged hadrons $dN/dz$ inside jets stemming from proton-proton collisions at $\sqrt{s}$ = 7 TeV center of mass energy can be described by a statistical jet-fragmentation model. This model combines microcanonical statistics and super-statistics induced by multiplicity fluctuations. The resulting scale dependence of the parameters of the model turns out to be similar to what was observed in electron-positron annihilations in Urmossy, Barnaf\"oldi, and Bir\'o.Comment: 7 pages, 8 figure

Generalised Tsallis Statistics in Electron-Positron Collisions

The scaling of charged hadron fragmentation functions to the Tsallis distribution for $0.01 \lessapprox x \lessapprox 0.2$ is presented for various $e^+e^-$ collision energies. A possible microcanonical generalisation of the Tsallis distribution is proposed, which gives good agreement with measured data up to $x\approx1$. The proposal is based on superstatistics and a $KNO$ like scaling of multiplicity distributions in $e^+e^-$ experiments.Comment: 9 pages, 18 figure

Jet mass dependence of fragmentation in positron-proton collisions

We propose the characterization of fragmentation functions by the energy fraction $\tilde{x}$ a hadron takes away from the energy of the jet measured in the frame co-moving with the jet. Besides, we propose the usage of the jet mass as the fragmentation scale $\tilde{Q}$. We show that these two Lorentz-invariant variables emerge naturally in a microcanonical ensemble with conserved four-momentum. Then, we construct a statistical hadronisation model, in which, two features of the hadronic final states in various high-energy reactions (power law spectra and negative-binomial multiplicity distributions) can be connected simply. Finally, we analyse the scale dependence of the parameters of the model (power of the spectrum and mean energy per hadron) in the $\phi^{3}$ theory. Fitting fragmentation functions in diffractive positron-proton collisions, we obtain a prediction for the jet mass dependence of the hadron multiplicity distribution inside jets

Fragmentation in the ϕ3 theory and the LPHD hypothesis

We present analytic solution of the Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) equation at leading order (LO) in the φ3 theory in 6 space-time dimen- sions. If the φ3 model was the theory of strong interactions, the obtained solution would describe the distribution of partons in a jet. We point out that the local parton- hadron duality (LPHD) conjecture does not work in this hypothetical situation. That is, treatment of hadronisation of shower partons is essential for the description of hadron distributions in jets stemming from proton-proton (pp) collisions at √s = 7 TeV and from electron-positron (e+e−) annihilations at various collision energies. We use a statistical model for the description of hadronisation