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Title: Recent results of the NA48/2 experiment

Abstract

The main goals of the NA48/2 experiment are a search for direct CP - violation in the charged kaon decays, a measurement of the pion scattering lengths using Ke4 decays and an investigation of some rare decays. By using large samples of K{+-} {yields} {pi}{+-}{pi}+{pi}- and K{+-} {yields} {pi}{+-}{pi}0{pi}0 decays, the asymmetries in the linear Dalitz plot slopes Ag = (g+ - g-)/(g+ + g-) were measured with high accuracy for both decay modes. The design of the experiment and the method of analysis provide good control of instrumental charge asymmetries in this measurement. Investigating the two neutral pion effective mass distribution in the K{+-} {yields} {pi}{+-}{pi}0{pi}0 decays, we observed cusp-like anomaly. This anomaly, never observed before, can be interpreted as an effect due to the final state charge exchange process {pi}+{pi}- {yields} {pi}0{pi}0 in the K{+-} {yields} {pi}{+-}{pi}+{pi}- decay. Comparison with theoretical models allowed to obtain a measurement of the pion-pion scattering length with a new technique which has a high precision.

Authors:
 [1]
  1. University of Sofia 'St. Kliment Ohridski', Faculty of Physics, 5 James Bourchier Blvd. 1164 Sofia (Bulgaria)
Publication Date:
OSTI Identifier:
21057128
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 899; Journal Issue: 1; Conference: 6. international conference of the Balkan Physical Union, Istanbul (Turkey), 22-26 Aug 2006; Other Information: DOI: 10.1063/1.2733108; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA). NA48-CERN Collaboration
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACCURACY; ASYMMETRY; CHARGE EXCHANGE; COMPARATIVE EVALUATIONS; CP INVARIANCE; DALITZ PLOT; EFFECTIVE MASS; KAONS MINUS; KAONS PLUS; MULTIPARTICLE SPECTROMETERS; PARTICLE DECAY; PARTICLE IDENTIFICATION; PION-KAON INTERACTIONS; PION-PION INTERACTIONS; PIONS MINUS; PIONS NEUTRAL; PIONS PLUS; SCATTERING LENGTHS

Citation Formats

Marinova, Evelina. Recent results of the NA48/2 experiment. United States: N. p., 2007. Web. doi:10.1063/1.2733108.
Marinova, Evelina. Recent results of the NA48/2 experiment. United States. doi:10.1063/1.2733108.
Marinova, Evelina. Mon . "Recent results of the NA48/2 experiment". United States. doi:10.1063/1.2733108.
@article{osti_21057128,
title = {Recent results of the NA48/2 experiment},
author = {Marinova, Evelina},
abstractNote = {The main goals of the NA48/2 experiment are a search for direct CP - violation in the charged kaon decays, a measurement of the pion scattering lengths using Ke4 decays and an investigation of some rare decays. By using large samples of K{+-} {yields} {pi}{+-}{pi}+{pi}- and K{+-} {yields} {pi}{+-}{pi}0{pi}0 decays, the asymmetries in the linear Dalitz plot slopes Ag = (g+ - g-)/(g+ + g-) were measured with high accuracy for both decay modes. The design of the experiment and the method of analysis provide good control of instrumental charge asymmetries in this measurement. Investigating the two neutral pion effective mass distribution in the K{+-} {yields} {pi}{+-}{pi}0{pi}0 decays, we observed cusp-like anomaly. This anomaly, never observed before, can be interpreted as an effect due to the final state charge exchange process {pi}+{pi}- {yields} {pi}0{pi}0 in the K{+-} {yields} {pi}{+-}{pi}+{pi}- decay. Comparison with theoretical models allowed to obtain a measurement of the pion-pion scattering length with a new technique which has a high precision.},
doi = {10.1063/1.2733108},
journal = {AIP Conference Proceedings},
number = 1,
volume = 899,
place = {United States},
year = {Mon Apr 23 00:00:00 EDT 2007},
month = {Mon Apr 23 00:00:00 EDT 2007}
}