Analyzing the correlation between thermal and kinematic parameters in various multiplicity classes within 7 and 13 TeV pp collisions

Abstract We investigate the transverse momentum spectra of identified particles at 7 and 13 TeV in pp collisions in the framework of the blast wave model with Tsallis statistics (TBW). Based on experimental data by ALICE Collaboration, we observe that the model describes the p T spectra well with the common Tsallis temperature ( T ) and flow velocity ( β T ) but separate non-extensive parameters ( q ) for baryons and mesons. The parameter dependence on multiplicity as well as on collision energy is investigated, and a strong dependence on the former while a weak dependence on the latter is reported. The extracted parameters in this work consist of the initial temperature ( T i ), the average transverse momentum (〈 p T 〉), the Tsallis temperature ( T ), the flow velocity ( β T ), and the non-extensive parameter ( q ). These parameters are found to increase a little with increasing energy, however, they (except the parameter q ) decrease significantly with decreasing multiplicity. We observe that β T drops to zero at high multiplicity , while, T and q do not change their behavior. Furthermore, our analysis explore the correlations among different parameters, including associations with the charged particle multiplicity per unit pseudorapidity ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:msub> <mml:mi>N</mml:mi> <mml:mi>ch</mml:mi> </mml:msub> <mml:mo stretchy="true">/</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi>η</mml:mi> <mml:mo stretchy="false">〉</mml:mo> </mml:math> ). The correlations between T and β T , T and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:msub> <mml:mi>N</mml:mi> <mml:mi>ch</mml:mi> </mml:msub> <mml:mo stretchy="true">/</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi>η</mml:mi> <mml:mo stretchy="false">〉</mml:mo> </mml:math> , β T and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:msub> <mml:mi>N</mml:mi> <mml:mi>ch</mml:mi> </mml:msub> <mml:mo stretchy="true">/</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi>η</mml:mi> <mml:mo stretchy="false">〉</mml:mo> </mml:math> , T i and 〈 p T 〉 and T i and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:msub> <mml:mi>N</mml:mi> <mml:mi>ch</mml:mi> </mml:msub> <mml:mo stretchy="true">/</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi>η</mml:mi> <mml:mo stretchy="false">〉</mml:mo> </mml:math> demonstrates a positive relationship, while, the correlation between T and q − 1, and q − 1 and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:msub> <mml:mi>N</mml:mi> <mml:mi>ch</mml:mi> </mml:msub> <mml:mo stretchy="true">/</mml:mo> <mml:mi mathvariant="normal">d</mml:mi> <mml:mi>η</mml:mi> <mml:mo stretchy="false">〉</mml:mo> </mml:math> is negative. Finally, we implement an extra flow correction on the T parameter. Our findings reveal that the Doppler-corrected temperature parameter aligns closely with the T in scenarios with lower multiplicities. However, as the multiplicity increases, a noticeable divergence emerges between these parameters, indicating a widening separation between them.

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