Inclusive meson production in 3.5 GeV pp collisions studied with the HADES spectrometer

Journal Article · Thu Aug 05 04:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3483432· OSTI ID:21426491

Rustamov, Anar ^[1]

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1. Helmholtzzentrum fuer Schwerionenforschung (GSI), Darmstadt (Germany)

We present the inclusive di-electron invariant-mass spectrum from p+p interactions at 3.5 GeV kinetic beam energy. It is a very important reference for the study of vector meson production off the nucleus, recently investigated by HADES in p+{sup 93}Nb reactions at the same beam energy. Up to invariant masses of 0.6 GeV/c{sup 2} the main contributions to the e{sup +}e{sup -} spectrum are {pi}{sup 0},{eta}, {omega} and {Delta} Dalitz decays. In the vector-meson region a clear peak corresponding to the {omega} direct decay is reconstructed with {approx_equal}2% mass resolution. Subtracting this peak from the spectrum allows to investigate additional sources, in particular the {rho} meson. Indeed, the latest results from HSD and UrQMD calculations show different distributions for the shape of the {rho} meson at these energies. Therefore it is important to experimentally understand the production mechanism of the {rho} meson in elementary reactions. Besides the spectral shape of the mesons, their inclusive production cross sections are also not known at these energies. Due to the large and flat acceptance of the HADES spectrometer for e{sup +}e{sup -} masses above 0.2 GeV/c{sup 2} and for P{sub T}<1GeV/c, acceptance corrections are to a large extent model independent. This allows us to extract the preliminary inclusive cross section values for the meson productions at these energies.

• OSTI ID: 21426491
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 1257; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
BARYON REACTIONS
BARYON-BARYON INTERACTIONS
BOSONS
CHARGED-PARTICLE REACTIONS
CHIRAL SYMMETRY
CROSS SECTIONS
DECAY
ELECTRONS
ELEMENTARY PARTICLES
ENERGY RANGE
ETA MESONS
FERMIONS
FIELD THEORIES
GEV RANGE
HADRON REACTIONS
HADRON-HADRON INTERACTIONS
HADRONS
INTERACTIONS
LEPTONS
MASS
MASS RESOLUTION
MASS SPECTRA
MATTER
MEASURING INSTRUMENTS
MESONS
MULTIPARTICLE SPECTROMETERS
NIOBIUM 93 TARGET
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUCLEON-NUCLEON INTERACTIONS
OMEGA-782 MESONS
PARTICLE DECAY
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PIONS
PIONS NEUTRAL
POSITRONS
PROTON REACTIONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
RESOLUTION
REST MASS
RHO-770 MESONS
SPECTRA
SPECTROMETERS
SYMMETRY
TARGETS
VECTOR MESONS