What information can we obtain from the yield ratio ${\pi }^{-}/{\pi }^{+}$ in heavy-ion collisions ?

Abstract

The recently reported data on the yield ratio ${\pi }^{-}/{\pi }^{+}$ in central rapidity region of heavy-ion collisions are analyzed by theoretical formula which accounts for Coulomb interaction between central charged fragment (CCF) consisting of nearly stopped nucleons with effective charge $Z_{\mbox{\scriptsize eff}}$ and charged pions produced in the same region of the phase space. The Coulomb wave function method is used instead of the usual Gamow factor in order to account for the finite production range of pions, $\beta$. For Gaussian shape of the pion production sources it results in a quasi-scaling in $\beta$ and $Z_{\mbox{\scriptsize eff}}$ which makes determination of parameters $\beta$ and $Z_{\mbox{\scriptsize eff}}$ from the existing experimental data difficult. Only sufficiently accurate data taken in the extreme small $m_T$-$m_{\pi }$ region, where this quasi-scaling is broken, could be used for this purpose.

7 pages, Latex type, 8 figures

References in corpus (4)

• Improved Coulomb Correction Formulae for Bose-Einstein Correlations
• Boundary and Coulomb Effects on Boson Systems in High-Energy Heavy-Ion Collisions
• Revisit of Coulomb effects on pi^{-}/pi^{+} ratio in heavy-ion collisions
• Coulomb corrections for Bose-Einstein correlations in whole momentum transfer region: Proposal of seamless fitting

Cited by in corpus (11)

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• Spectator induced electromagnetic effect on directed flow in heavy ion collisions
• The Spectator Electromagnetic Effect on Charged Pion Spectra in Peripheral Ultrarelativistic Heavy-Ion Collisions
• Effects of retarded electrical fields on observables sensitive to the high-density behavior of nuclear symmetry energy in heavy-ion collisions at intermediate energies
• Central Coulomb Effects on Pion Interferometry
• Quasiscaling in the analysis of the yield ratio ${\pi }^{-}/{\pi }^{+}$: Mathematical structure and estimation of source size
• Coulomb Effect: A Possible Probe for the Evolution of Hadronic Matter
• Analysis of Bose-Einstein correlations in e+e- -> W+W- events including final state interactions