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Extracting temperature and transverse flow by fitting transverse mass spectra and HBT radii together

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 Added by Ronghua He
 Publication date 2016
  fields
and research's language is English




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Single particle transverse mass spectra and HBT radii of identical pion and identical kaon are analyzed with a blast-wave parametrization under the assumptions local thermal equilibrium and transverse expansion. Under the assumptions, temperature parameter $T$ and transverse expansion rapidity $rho$ are sensitive to the shapes of transverse mass $m_text T$ spectrum and HBT radius $R_text{s}(K_text T)$. Negative and positive correlations between $T$ and $rho$ are observed by fitting $m_text{T}$ spectrum and HBT radius $R_text s (K_text T)$, respectively. For a Monte Carlo simulation using the blast-wave function, $T$ and $rho$ are extracted by fitting $m_T$ spectra and HBT radii together utilizing a combined optimization function $chi^2$. With this method, $T$ and $rho$ of the Monte Carlo sources can be extracted. Using this method for A Multi-Phase Transport model (AMPT) at RHIC energy, the differences of $T$ and $rho$ between pion and kaon are observed obviously, and the tendencies of $T$ and $rho$ vs collision energy $sqrt{s_text{NN}}$ are similar with the results extracted directly from the AMPT model.

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