LXXV International Conference «NUCLEUS – 2025. Nuclear physics, elementary particle physics and nuclear technologies»

Modeling collective effects in the extended multi-pomeron exchange model

3 Jul 2025, 11:25

20m

90(3011) (Санкт-Петербургский Государственный Университет )

Oral Section 4. Relativistic nuclear physics, high-energy and elementary particle physics. 4. Relativistic nuclear physics, high-energy and elementary particle physics: Theory

Speaker

Vladimir Kovalenko (Saint Petersburg State University)

Description

A new generalization of the Multipomeron exchange model (MEM) [1-3] for pp collisions is proposed, taking into account the effect of event-by-event string tension fluctuations [4]. It is shown that the new version of the MEM correctly reproduces the characteristic thermal behavior of $p_T$ spectra in a wide energy range. In addition, the new generalization of the MEM improves the description of multiplicity distributions by replacing the Poisson distribution from one string with the discrete Gaussian distribution [5]. Calculations show that the new version of the MEM correctly reproduces the characteristic oscillating behavior of modified combinants in pp collisions over a wide energy range [5]. Simultaneously, the $p_T$-multiplicity correlation functions are shown to be satisfactorily described together with the multiplicity-dependent $p_T$ spectrum [6]. Using results of the Glauber model at the partonic level [7-8], the model is applied for describing the relativistic heavy-ion collisions and strongly intensive fluctuations are calculated as a function of centrality .

The authors acknowledge Saint-Petersburg State University for a research project 103821868.

References:

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