Pion-pion correlations in pp at sqrt(S)=900GeV In the EPOS model (ver. 1.90)

1. Pion-pion correlations in pp at sqrt(S)=900GeV In the EPOS model (ver. 1.90) pp@900GeV 2*106 events generated by EPOS Cut on pions: 0.05<pT<2.0GeV/c |y|<1 π+π+ correlation function: QS weight (Coulomb switched off) 1D fit – superposition of two Gaussians: R=1+ λ1exp(-R12Qinv2) + λ2(-R22Qinv2) R.Lednicky, T.Progulova Z.Phys.C 55, 295(1992) Look at: Total, “direct” and “secondary”(from decay) pions K.Mikhailov, December 2009

2. Fathers of π+ in pp@900GeV pp sqrt(s)=900GeV EPOS ver1.90 Code Decay Rate -2230 antiΣ-→nπ+ 0.89 % -2221 antiΔ-→nπ+ 1.53 % -2130 antiΛ→pπ+ 1.82 % -231 antiK*0→Kπ+ 2.86 % -1 direct pion30.24 % 20 Ks0→π-π+ 7.49 % 111 ρ0 →π-π+ 14.63 % 121 ρ+ →π0π+ 14.05 % 131 K*+→Kπ+ 2.95 % 220 η→π-π+π0 3.72 % 221 ω→π-π+π0 11.95 % 330 η'→ηπ-π+ 0.81 % 1111 Δ++→pπ+ 1.19 %

3. CF π+π+ in pp@900GeV

4. Primary and seconadary π+π+

5. Primary and seconadary π+π+

6. ρ, ω and K* inπ+π+ CF π+dirπ+ρ π+dirπ+ω π+dirπ+K*

7. 3D fit and Projections Standard 3D fit of EPOS pipi CF (2e6 events): Chi2/NDF = 1.1 Lambda = 0.27 +/- 0.01 R_out = 0.84 +/- 0.02 R_side = 0.73 +/- 0.01 R_long = 1.42 +/- 0.02 Projections below:

8. Pion-pion correlations in pp at sqrt(S)=900GeV In the QGSM model pp@900GeV 3*106 events generated by QGSM Quark Gluon String Model tuned for pp LHC by UiO group (L. Bravina, E.Zabrodin et al) Cut on pions: 0.05<pT<2.0GeV/c |y|<1 π+π+ correlation function: QS weight and QS+Coulomb 1D fit – superposition of two Gaussians: R=1+ λ1exp(-R12Qinv2) R=1+ λ1exp(-R12Qinv2) + λ2(-R22Qinv2) R.Lednicky, T.Progulova Z.Phys.C 55, 295(1992) R=1-λ-ξ+ λ KCoul (1+exp(-R2Qinv2)) + ξKCoul(1+ a4/(a2+Qinv2)2) A.Kisiel Look at: Total, in progress: “direct” and “secondary”(from decay) pions Malinina Liudmila, December 2009

9. QS only !

10. QS + Coulomb

11. The work is under way.

12. Happy New Year !!!