Köln 2004 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HK: Physik der Hadronen und Kerne
HK 14: Poster Session: Heavy Ions
HK 14.3: Poster
Dienstag, 9. März 2004, 13:30–15:30, Foyer
Why a long-lives source can be compatible with HBT measurements — •Thorsten Renk — Technische Universität München
The common interpretation of HBT data measured at top SPS energies leads to apparent source lifetimes of 6–8 fm/c and emission duration of approximately 2–3 fm/c. We investigate a scenario with continuous pion emission from a long-lived (∼ 17 fm/c) thermalized source in order to show that it is not excluded by the data. Starting from a description of the source’s spacetime expansion based on gross thermodynamical properties which is well tested for several observables, we introduce the pion emission function with a contribution from continuous emission during the source’s lifetime and another contribution from final breakup and proceed by calculating the HBT parameters Rout and Rside. The results are compared with experimental data measured at SPS for 158 AGeV central Pb-Pb collisions. We achieve good agreement with the data, provided that some minor modifications of the fireball evolution scenario are made. We find that the parameter Rout is not sensitive to the fireball lifetime, but only to the duration of the final breakup, in spite of the fact that emission takes place throughout the whole lifetime.
Work supported in part by BMBF and GSI.