21–25 Sept 2009
INFN - Laboratori Nazionali di Frascati
Europe/Rome timezone
In the following lectures Prof. Zbigniew Was will present main ideas of Monte Carlo methods as used in simulations of physics processes for high energy physics experiments.
In the presentation Prof. Was will use QED distributions because there, in principle, everything can be calculated with arbitrary precision and simulation of tau decays, because in this case input from models to be validated by data is essential.

Principles of Monte Carlo method
  • Rejection
  • Importance Sampling
  • Branches of the Generation
  • Crude Distribution Overall Normalization and Rejection again
  • What is Markovian and non-Markovian algorithm
Phase space
  • Parametrization of Exact n-body Phase Space
  • Multichannel Generation
  • Phase Space Semi-Factorization
Matrix element, case when it is calculable
  • Convergence and Theoretical Errors in case of Experimental Cuts
  • Soft Photons can be ignored
  • QED Infrared Singularities and Negative Weights
  • Useful Properties of Matrix Elements, factorization and exclusive exponentiation
Matrix element, case when it must be deduced from data
  • Matrix Element for Tau Decay
  • Hadronic current constraints from Lorentz and (hints?) from chiral and isospin symmetry
  • Relation to Measurable Distributions
Special Monte carlo techniques
  • Correlated Samples
  • Applications to remove unwanted (known) physics such as bremsstrahlung in decays
  • Event weighted with alternative models for fits

Bibliography (incomplete):
1) Notes of my lectures on similar topic http://cern.ch/~wasm/public/zakopane.ps.gz
2) References on TAUOLA and PHOTOS which I will use as source of examples. In particular:
3) ``PHOTOS: A Universal Monte Carlo for QED radiative corrections. Version 2.0'' E. Barberio and Z. Was Comput. Phys. Commun. 79, 291 (1994)
4) ``The Tau Decay Library Tauola: Version 2.4''S. Jadach, Z. Was, R. Decker and J. H. Kuhn Comput. Phys. Commun.76, 361 (1993)
5) ``Scalar QED, NLO and PHOTOS Monte Carlo'' G. Nanava and Z. Was Eur. Phys. J. C51, 569 (2007)
6) ``Library of SM and anomalous W W gamma couplings for the e+ e- --> f anti-f (n)gamma Monte Carlo programs'', A. Jacholkowska, J. Kalinowski and Z. Was Comput. Phys. Commun. 124, 238 (2000)



Starts
Ends
Europe/Rome
INFN - Laboratori Nazionali di Frascati
Auditorium B. Touschek
Via Enrico Fermi 40 I-00044 Frascati (Rome)
Teacher : Prof. Zbigniew Was (IFJ PAN)

Local Chairs : Danilo Babusci (INFN-LNF), Graziano Venanzoni (INFN - LNF)

Secretary: Rita Bertelli (INFN-LNF)
Tel.: ++39 06 9403 2740
Fax: ++39 06 9403 2582