Direct measurement of the Chudakov effect

Virkus T., Thomsen H. D., Uggerhoj E., Uggerhoj U. I., Ballestrero S., Sona P., ...More

PHYSICAL REVIEW LETTERS, vol.100, no.16, 2008 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 100 Issue: 16
  • Publication Date: 2008
  • Doi Number: 10.1103/physrevlett.100.164802
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Istanbul University Affiliated: No


Experimental results for the restricted energy loss of pairs created from 1-178 GeV photons in a thin Au target and subsequently passing a CCD detector are presented. It is shown that pairs-when detected close to the creation vertex-suffer a reduced energy loss due to the internal screening of the charges constituting the pair. Furthermore, the ability to measure directly the energy of the pair by calorimetry enables a comparison with theory as a function of energy. The observed phenomenon is in good qualitative agreement with general expectations from the Chudakov effect but indicates a quantitative disagreement with either of two mutually disagreeing theories.