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Related papers: $\gamma\gamma$ Event Generators

200 papers

Event generators in high-energy nuclear and particle physics play an important role in facilitating studies of particle reactions. We survey the state-of-the-art of machine learning (ML) efforts at building physics event generators. We…

High Energy Physics - Phenomenology · Physics 2021-12-30 Yasir Alanazi , N. Sato , Pawel Ambrozewicz , Astrid N. Hiller Blin , W. Melnitchouk , Marco Battaglieri , Tianbo Liu , Yaohang Li

The light unflavoured meson $\eta/\eta^{\prime}$ decays are valuable for testing non-perturbative quantum chromodynamics and exploring new physics beyond the Standard Model. This paper describes a series of event generators, including…

High Energy Physics - Experiment · Physics 2017-12-11 Nian Qin , Zhen-Yu Zhang , Shuang-Shi Fang , Xiang Zhou , Lin-Lin Du , Hao-Xue Qiao

The search for quartic anomalous gauge couplings at LEP requires appropriate predictions for the radiative processes e+ e- \to \nu\bar\nu \gamma\gamma, e+ e- \to q\bar{q}\gamma\gamma and e+ e- \to 4 fermions+\gamma. Matrix elements are…

High Energy Physics - Phenomenology · Physics 2009-11-07 G. Montagna , M. Moretti , O. Nicrosini , M. Osmo , F. Piccinini

We analyze various perturbative mechanisms for the production of jet events containing rapidity gaps in $e^+e^-$ annihilation at LEP200 energies. We found that the processes $e^+e^- \to \gamma^* \gamma^*, \gamma^* Z, Z Z, WW \to 4~ jets$…

High Energy Physics - Phenomenology · Physics 2009-09-25 H. J. Lu

I describe the optimizing matrix element generator O'Mega and Wolfgang Kilian's event generator generator WHIZARD. These tools cooperate in the automated production of efficient unweighted event generators for linear collider physics.

High Energy Physics - Phenomenology · Physics 2009-10-31 Thorsten Ohl

A real photon has a complicated nature, whereby it may remain unresolved or fluctuate into a vector meson or a perturbative q-qbar pair. Based on this picture, we previously presented a model for gamma-p events that is based on the presence…

High Energy Physics - Phenomenology · Physics 2007-05-23 Gerhard A. Schuler , Torbjorn Sjostrand

A partisan review of some of the most important $\gamma\gamma$ channels accessible at LEP 2, with special stress on the measurement of the photon structure function $F_{2}^{\gamma}$ and on associated problems with Monte Carlo modelling.

High Energy Physics - Experiment · Physics 2008-11-26 D. J. Miller

The Searches Working Group discussed a variety of topics relating to present and future measurements of searches at LEP 2. The individual contributions are included separately.

A real photon has a complicated nature, whereby it may remain unresolved or fluctuate into a vector meson or a perturbative q-qbar pair. In gamma-gamma events, this gives three by three combinations of the nature of the two incoming…

High Energy Physics - Phenomenology · Physics 2011-02-15 Gerhard A. Schuler , Torbjörn Sjöstrand

The precise knowledge of the beam energy, E_beam, at the LEP collider is important to reduce the systematic uncertainty on the W mass. The measurements by the LEP energy group can be cross checked using Z recoil events. Preliminary results…

High Energy Physics - Experiment · Physics 2007-05-23 Christian Rosenbleck

This contribution lists challenges of Monte Carlo event generators for future lepton, especially linear colliders. A lot of the recent development benefits from the achievements at the Large Hadron Collider (LHC), but several aspects are…

High Energy Physics - Phenomenology · Physics 2024-12-19 Jürgen Reuter

Double-tag events in two-photon collisions are studied using the L3 detector at LEP centre-of-mass energies from root(s)=189 GeV to 209 GeV. The cross sections of the e+e- -> e+e- hadrons and gamma*gamma* -> hadrons processes are measured…

High Energy Physics - Experiment · Physics 2012-08-27 L3 Collaboration

A calculation of the hard bremsstrahlung process e+ e- -> mu+ mu- gamma gamma is presented and compared with recent results from the L3 Collaboration.

High Energy Physics - Phenomenology · Physics 2009-10-22 K. Kołodziej , F. Jegerlehner , G. J. van Oldenborgh

To improve the performance of long text generation, recent studies have leveraged automatically planned event structures (i.e. storylines) to guide story generation. Such prior works mostly employ end-to-end neural generation models to…

Computation and Language · Computer Science 2022-10-20 Chen Tang , Zhihao Zhang , Tyler Loakman , Chenghua Lin , Frank Guerin

Radiative returns to the Z resonance (Zgamma events) provide a method to determine the centre-of-mass energy of the high energy e+e- colliders and already at LEP2. The method is applied for the data collected with the ALEPH detector in 1997…

High Energy Physics - Experiment · Physics 2012-08-27 ALEPH Collaboration

The cross sections for the reaction $\gamma\gamma\rightarrow 4\ell$ in proton--proton collisions are calculated at the LHC energies. We show that the purely electroweak process $\gamma\gamma\rightarrow 4\ell$ can be studied at the LHC and…

High Energy Physics - Phenomenology · Physics 2016-08-24 Mateusz Dyndal , Laurent Schoeffel

The HERWIG event generator was widely used throughout the workshop, particularly in the emulation of Supersymmetric and Higgs processes in the context of the Minimal Supersymmetric Standard Model. We briefly review here its main features in…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. Moretti

This paper proposes a distributed scheme with different estimators for the event-triggered formation control of polytopic homogeneously scheduled linear parameter-varying (LPV) multi-agent systems (MAS). Each agent consists of a…

Systems and Control · Electrical Eng. & Systems 2023-01-02 Gerald Gebhardt , Hamideh Saadabadi , Herbert Werner

We have developed an event generator for direct-photon production in hadron collisions, including associated two-jet production in the framework of the GR@PPA event generator. The event generator consistently combines $\gamma$ + 2-jet…

High Energy Physics - Phenomenology · Physics 2016-06-22 Shigeru Odaka , Yoshimasa Kurihara