Measurement of the $\omega$ Meson in pp Collisions at the LHC with ALICE

Jun 2, 2020, 7:30 AM
1h 20m


Poster Jets and High Momentum Hadrons Poster session


Jens Robert Luhder (Westfaelische Wilhelms-Universitaet Muenster (DE))


ALICE is a dedicated heavy-ion experiment and focusses on the properties of the Quark-Gluon Plasma (QGP), a state of strongly interacting matter expected to be formed in heavy-ion collisions.
When performing proton-proton collisions, the energy densities reached are in principle not sufficient to form this medium and hence measurements in this system serve as a baseline to understand the influences of the QGP on the particle production.
Furthermore, cross sections of neutral mesons are needed to test QCD-based theory predictions and to constrain Fragmentation Functions as well as Parton Distribution Functions at high momentum.

This poster will cover the measurement of the invariant cross sections of the $\omega$-meson at mid-rapidity in pp collisions with a center of mass energy of $\sqrt{s}=13\,$TeV produced at the LHC Run2 and measured by ALICE.
The $\omega$ is reconstructed via $\omega \rightarrow \pi^+ \pi^- \pi^0$, where the $\pi^0$ decays further in two photons.
In ALICE, the measurement of photons is performed in two different ways:
The first method measures photons via their energy deposits in electromagnetic calorimeters.
The second method is called PCM (Photon Conversion Method) as photons may convert to e$^{+}$-e$^{-}$ pairs when interacting with the detector material. While the e$^{+}$-e$^{-}$ pairs from conversions are identified and measured with help of the Time Projection Chamber (TPC), the charged pions are measured using information of the Inner Tracking System (ITS) in addition.

Contribution type Poster
Track Jets and High Momentum Hadrons
Collaboration (if applicable) ALICE

Primary author

Jens Robert Luhder (Westfaelische Wilhelms-Universitaet Muenster (DE))

Presentation materials