Abstract
The PHENIX collaboration presents first measurements of low-momentum (0.41 GeV/c) direct-photon yield dNγdir/dη is a smooth function of dNch/dη and can be well described as proportional to (dNch/dη)α with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high pT (>5 GeV/c), but when results from different collision energies are compared, an additional sNN-dependent multiplicative factor is needed to describe the integrated-direct-photon yield. © 2019 authors. Published by the American Physical Society.
Original language | English |
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Article number | 022301 |
Journal | Physical Review Letters |
Volume | 123 |
Issue number | 2 |
DOIs | |
Publication status | Published - 2019 Jul 10 |
Subject classification (UKÄ)
- Subatomic Physics
Free keywords
- Heavy ions
- Photons
- Au+Au collisions
- Collision energies
- Collision systems
- Large Hadron Collider
- Multiplicative factors
- Relativistic Heavy Ion Collider
- Scaling behavior
- Ultrarelativistic heavy ion collision
- Colliding beam accelerators