Event topology and multiplicity dependence of $\rm{K}^{∗}(892)^{0}$ production in proton+proton collisions with ALICE at the LHC and probing TeV collisions through particle production and transport properties

Year
2021
Degree
PhD
Author
Rath, Rutuparna
Mail
rutuparna.rath@cern.ch
Institution
Indian Institute of Technology Indore (IN)
Abstract

In this thesis, we have studied the effect of event-topology (transverse spherocity) on the production of $\rm{K}^{∗}(892)^{0}$ resonance particle, which has a lifetime of $\sim$10$^{-24}s$. This lifetime is comparable to the hadronic phase lifetime of the system produced in ultra-relativistic nucleon-nucleon or nuclear collisions. $\rm{K}^{∗}(892)^{0}$ is sensitive to the hadronic phase effects such as rescattering and regeneration processes, which might affect the yield and shape of the transverse momentum spectra. In addition, event shape observables like transverse spherocity are sensitive to the hard and soft processes. They are useful tools to distinguish the isotropic and jetty-dominated events in pp collisions. Studying the dependence of the yield of resonance on transverse spherocity and multiplicity allows us to understand the resonance production mechanism with event topology and system size, respectively. In this thesis, we observe that low multiplicity pp collisions are more dominated by jetty-like events whereas high multiplicity pp collisions are highly populated with isotropic-like events. In high multiplicity pp collisions, it is found that the low transverse momentum region is more dominated by isotropic-like events whereas the high transverse momentum region is dominated mostly by jetty-like events. Moreover, we have also studied the integrated yield, mean transverse momentum, and particle ratio to long-lived stable particles. Furthermore, the measurements in small systems done using the ALICE detector are compared with results obtained from models such as PYTHIA8, EPOS-LHC, etc. Also, these results are helpful for the tuning of Quantum Chromodynamics inspired event generators. In this thesis, we have also carried out several phenomenological studies to understand the behaviour of chemical and kinetic freeze-out parameters in pp collisions, the dependence of transport coefficients like thermal conductivity, electrical conductivity, and hall conductivity with temperature, chemical potential, and strength of magnetic field using relativistic Boltzmann transport equation with relaxation time approximation and the particle production in nuclear collisions with deformed Xe nuclei using A Multi-Phase Transport model (AMPT).

Supervisors
Sahoo, Raghunath (IIT Indore)
Report number
CERN-THESIS-2021-236
Date of last update
2021-12-21