These fields are sufficiently intense to produce large numbers of electron, muon and tauon pairs, as well as other more massive particles. « lessĭuring the collision of heavy-ions at relativistic velocities, law transient electromagnetic fields are formed in a space-time region near the collision. References: and references in this article. At lower energies (i.e., at the CERN SPS), caution should be exercised because STARlight does not account for the longitudinal momentum transfer to the nucleus this is larger at low beam energies. Restrictions: The program is focused on ultra-relativistic collisions at Brookhaven's RHIC (Relativistic Heavy Ion Collider) and CERN's LHC (Large Hadron Collider), with final states that are visible in a central detector. Particle decays and the final angular distributions are calculated for each event. With these look-up tables, the program generates final states. For certain final states, a second two-dimensional look-up table, giving the transverse momentum distribution, as a function of rapidity, is also used. The dimensions of the table are selectable, allowing the user to choose the desired accuracy. Solution method: The program generates a two dimensional look-up table of the production cross-section as a function of final state rapidity and mass. The second step includes the decay of any unstable particles produced in the reaction, with appropriate consideration of particle spins and parity. Second, STARlight generates Monte Carlo events which can be used to determine cross-sections within specific kinematic constraints or for studies of detector efficiencies. First, it calculates the cross-sections for the reaction of interest, as a function of W (photon–Pomeron or two-photon center of mass energy), Y (final state rapidity) and pT (final state transverse momentum). Nature of problem: The cross-section for ultra-peripheral collisions is obtained by integrating the photon fluxes in transverse impact parameter space, subject to the requirement (which is also impact parameter dependent) that the colliding nuclei do not interact hadronically. Program summary Program Title: STARlight (v2.2) Program Files doi: Licensing provisions: GNU GPLv3 Programming Language: C++ External Routines: PYTHIA 8.2 and DPMJET 3.0 are needed for some final states. We present a program, STARlight, that calculates the cross-sections for a variety of UPC final states and also creates, via Monte Carlo simulation, events for more » use in determining detector efficiency. In these interactions, the collision geometry plays a major role. Photonuclear interactions produce vector meson states or more general photonuclear final states, while two-photon interactions can produce lepton or meson pairs, or single mesons. In these collisions, the two colliding nuclei interact electromagnetically, via two-photon or photonuclear interactions, but not hadronically they effectively miss each other. Ultra-peripheral collisions (UPCs) have been a significant source of study at RHIC and the LHC. Authors: Bottcher, C Strayer, M R Publication Date: Research Org.: Oak Ridge National Lab., TN (USA) Sponsoring Org.: DOE/ER OSTI Identifier: 7253146 Report Number(s): CONF-8906270-3 ON: DE90008404 TRN: 90-026782 DOE Contract Number: AC05-84OR21400 Resource Type: Conference Resource Relation: Conference: Summer school of computational atomic and nuclear physics, Sewanee, TN (USA), 26 Jun - Country of Publication: United States Language: English Subject: 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS ELECTROMAGNETIC INTERACTIONS PAIR PRODUCTION MUON PAIRS TAU PARTICLES ALGORITHMS CROSS SECTIONS ELECTRONS EQUATIONS OF MOTION FORM FACTORS HAMILTONIANS HEAVY ION REACTIONS MATRIX ELEMENTS MONTE CARLO METHOD PION MINUS-PROTON INTERACTIONS S MATRIX SEMICLASSICAL APPROXIMATION T INVARIANCE TRANSVERSE MOMENTUM BASIC INTERACTIONS CHARGED-PARTICLE REACTIONS DIFFERENTIAL EQUATIONS ELEMENTARY PARTICLES EQUATIONS FERMIONS HADRON-HADRON INTERACTIONS HEAVY LEPTONS INTERACTIONS INVARIANCE PRINCIPLES LEPTONS LINEAR MOMENTUM MATHEMATICAL LOGIC MATHEMATICAL OPERATORS MATRICES MESON-BARYON INTERACTIONS MESON-NUCLEON INTERACTIONS NUCLEAR REACTIONS PARTIAL DIFFERENTIAL EQUATIONS PARTICLE INTERACTIONS PARTICLE PROPERTIES PION-NUCLEON INTERACTIONS PION-PROTON INTERACTIONS POSTULATED PARTICLES QUANTUM OPERATORS 645202* - High Energy Physics- Particle Interactions & Properties-Theoretical- Electromagnetic Interactions & Properties
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