Two Pion Correlation In Heavy Ion CollisionsXinhua Li, Jingbo Zhang, Nu Xu |
| The
extracted source parameters Ri (i = side, out, long) are
very close to the two particle separatation
R1-R2. Good news!!! However, this is only true
for Au+Au collisions, for p+p collisions the two parameter sets do not
match. In general, the ones from C2 is much smaller than that from
source distributions and the source is not in Gaussian shape. Question whether the pT dependence speaks about the hydro flow remains though. |
| Due to the decay, the correlation functions are not perfect Gaussian shape and the lambda parameter is less than unity. However, with the time window, Δ=10 fm/c, the correlation functins are much closer to the Gaussian shape and lambda is unity. This means that whence sequential freeze-out occurs, weather due to decay or expansion or due to other mechanism, the correlation function is destored and the lambda parameter becomes less than 1! The sequential freeze-out, at least from the model used here, is more general than resonance decay or expansion! The experimental measured lambda parameter is less than 1 is, in fact, a clear evidence of sequential freeze-out in heavy ion collisions. |
| Due to the decay, the correlation functions are not perfect Gaussian shape and the lambda parameter is less than unity. However, with the time window, 10 < time < 30 fm/c, the correlation functins are much closer to the Gaussian shape and lambda is unity. Again, this means that whence sequential freeze-out occurs, weather due to decay or expansion or due to other mechanism, the correlation function is destored and the lambda parameter becomes less than 1! |
| Clearly, the mT dependence
of the source size parameters are similar for both p+p and Au+Au
collisions. Why? Why? Why? It is ok for Rlong, but I do not understand the Rside and Rout behavior! |