Identified particle femtoscopy in Pb-Pb collisions with ALICE at the LHC

20 May 2014, 16:30
spectrum (darmstadtium)



Board: I-04
Poster Correlations and Fluctuations Poster session


Hans Beck (Johann-Wolfgang-Goethe Univ. (DE))


Two-particle momentum correlations carry important information about the space-time characteristics of the particle emission region. Femtoscopic correlations at low relative momentum arise from quantum statistics (for identical particle pairs) and final-state interactions (for both identical and non-identical pairs) and are used to probe the homogeneity lengths of the emitting source. Hydrodynamic models predict a decrease of these homogeneity lengths with increasing pair transverse mass ($m_{\rm T}$), which has been confirmed by pion analyses. Femtoscopic analyses of heavier particles are able to extend the $m_{\rm T}$ range and thus further constrain theoretical models. Femtoscopic correlations are also important for studying two-particle systems whose scattering interaction is not well-known. They can be used to extract information about the interaction, such as scattering lengths and effective ranges. We present measurements of two-particle femtoscopic correlations of several identical and non-identical systems of mesons and baryons measured by ALICE in $\sqrt{s_{\rm NN}}$ = 2.76 TeV Pb-Pb collisions. One-dimensional radii ($R_{\rm inv}$) and $\lambda$ parameters for various particle types are extracted, with which an approximate $m_{\rm T}$-scaling is seen beyond the range of previous pion analyses. Fit parameters are also compared with theoretical model predictions.
On behalf of collaboration: ALICE

Primary author

Hans Beck (Johann-Wolfgang-Goethe Univ. (DE))

Presentation Materials