Guest webpage https://www.hugo-riemann.de/tord/doc/Jochem_Fleischer/ for Prof. a.D. Burkhard Jochem Fleischer, Univ. Bielefeld (1937 - 2013)

Prof. Dr. a.D. Burkhard Jochem Fleischer (1937 - 2013)

Publications

PhD Students

Research topics

• Calculation of higher-order loop corrections to selected observables in the Standard Model of elementary particle physics;

• Delevlopment of new tensor reduction techniques for n-point one-loop Feynman integrals with arbitrary kinematics;

• Formulation and applications of the Mellin-Barnes approach to Feynman integrals.

Together with T.R. he studied also, with less effort, the general analytical representation of arbitrary one-loop Feynman integrals in arbitrary dimensions.
The basics were worked out in J. Fleischer, F. Jegerlehner, O. Tarasov, A New hypergeometric representation of one loop scalar integrals in d dimensions, published in Nucl.Phys. B672 (2003) 303.
The aim was to develop an algorithm for applications in arbitrary kinematics. This was beyond the scope of the FJT article, but of potential interest for applications.
This project was more ambitious than expected and was much later finished with a new approach:
K.H.Phan, T. Riemann, Scalar 1-loop Feynman integrals as meromorphic functions in space-time dimension d, published in Phys.Lett. B791 (2019) 257.

A summary of results from work of Jochem Fleischer with Andrea Almasy, Ievgen Dubovyk, Janusz Gluza and T.R. on the reduction of 5-point to 7-point one-loop Feynman integrals was basically finished few days before Jochem left us. It is yet mainly unpublished; but see a talk by T.R.

Obituary of Bielefeld University (29 July 2014)

Selected recent talks

2012
"Tensor reduction for one-loop Feynman diagrams"
Talk given at Int. Workshop on Frontiers in Perturbative Quantum Field Theory, Bielefeld University, September 10 - 12, 2012, conf. information

2011

• "NLO tensor reductions"
  Talk given at Int. Conference Matter to the depest, Ustron, Poland, September 2011, conf. information
  
  2010
  
• "NLO tensor reductions"
  Talk given at Silesian Univ. Katowice, Oct. 26, 2010
  
• "NLO tensor reductions for large and small Gram determinants"
  Talk given at Conference on "QCD at the LHC", ETC, Trento, Italy, Sep. 26, 2010
  
• "New results for NLO tensor reductions"
  Talk given at Meeting of SFB/TR9, Berlin, Humboldt-Universität zu Berlin, March 22, 2010
  SFB/TR 9 Meeting 2010
  
  2009
  
• "Reduction of 1-loop Tensor integrals"
  lecture given at CALC 2009, "Helmholtz International School-Workshop on Calculations for Modern and Future Colliders", July 2009, JINR, Dubna, Russia
  HISS-Calc 2009
  
  2007
  
• "Application of Mellin-Barnes representation to the calculation of massive five-point functions in Bhabha scattering"
  Talk given at the Conference on Frontiers in Perturbative Quantum Field Theory, June 14-16 2007, ZiF, Bielefeld
  ZiF Conference 2007