Aug 12 – 18, 2012
US/Eastern timezone

If you have any questions about the details of the program please contact Bolek Wyslouch

Measurement of Low Mass Electron-Positron Pairs with ALICE Low Mass e+e--Pair

Aug 16, 2012, 4:00 PM
Regency 1/3 and Ambassador

Regency 1/3 and Ambassador

Poster Electroweak probes Poster Session Reception


Christoph Baumann (Johann-Wolfgang-Goethe Univ. (DE)) Markus Kohler (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))


Direct photons are an important probe of the hot and dense medium created in heavy-ion collisions because they do not interact with the medium and therefore carry information of all stages of the collision. At low momenta, thermal emission, which would provide the ideal measurement of temperature of the quark-gluon plasma, is expected to dominate over other sources of direct photons. However, since the fraction of thermal photon is small, the measurement of direct photons is notoriously difficult due to the large background from hadronic decay photons. These difficulties can be overcome by measuring virtual photons detected as internal conversion into electron-positron pairs. ALICE uses its excellent tracking and particle identification capabilities at very low momenta to perform this measurement in the Pb-Pb collisions collected in 2011 at sqrt(s_NN) = 2.76 TeV. Details of the measurement and status of the analysis will be presented.

Primary author

Collaboration ALICE (CERN Geneva, Switzerland)


Dr Alberica Toia (Johann-Wolfgang-Goethe Univ. (DE)) Markus Kohler (GSI - Helmholtzzentrum fur Schwerionenforschung GmbH (DE))

Presentation materials

There are no materials yet.