Find in Library

Transverse momentum spectra of negative and positive pions produced at mid-(pseudo)rapidity in inelastic or non-single-diffractive proton-proton collisions over a center-of-mass energy, <inline-formula> <math display="inline"> <semantics> <msqrt> <mi>s</mi> </msqrt> </semantics> </math> </inline-formula>, range from a few GeV to above 10 TeV are analyzed by the blast-wave fit with Boltzmann (Tsallis) distribution. The blast-wave fit results are well fitting to the experimental data measured by several collaborations. In a particular superposition with Hagedorn function, both the excitation functions of kinetic freeze-out temperature (<inline-formula> <math display="inline"> <semantics> <msub> <mi>T</mi> <mn>0</mn> </msub> </semantics> </math> </inline-formula>) of emission source and transverse flow velocity (<inline-formula> <math display="inline"> <semantics> <msub> <mi>β</mi> <mi>T</mi> </msub> </semantics> </math> </inline-formula>) of produced particles obtained from a given selection in the blast-wave fit with Boltzmann distribution have a hill at <inline-formula> <math display="inline"> <semantics> <mrow> <msqrt> <mi>s</mi> </msqrt> <mo>≈</mo> <mn>10</mn> </mrow> </semantics> </math> </inline-formula> GeV, a drop at dozens of GeV, and then an increase from dozens of GeV to above 10 TeV. However, both the excitation functions of <inline-formula> <math display="inline"> <semantics> <msub> <mi>T</mi> <mn>0</mn> </msub> </semantics> </math> </inline-formula> and <inline-formula> <math display="inline"> <semantics> <msub> <mi>β</mi> <mi>T</mi> </msub> </semantics> </math> </inline-formula> obtained in the blast-wave fit with Tsallis distribution do not show such a complex structure, but a very low hill. In another selection for the parameters or in the superposition with the usual step function, <inline-formula> <math display="inline"> <semantics> <msub> <mi>T</mi> <mn>0</mn> </msub> </semantics> </math> </inline-formula> and <inline-formula> <math display="inline"> <semantics> <msub> <mi>β</mi> <mi>T</mi> </msub> </semantics> </math> </inline-formula> increase generally quickly from a few GeV to about 10 GeV and then slightly at above 10 GeV, there is no such the complex structure, when also studying nucleus-nucleus collisions.