Search

Your search keyword '"O. Wigger"' showing total 12 results
Start Over Author "O. Wigger" Topic high energy physics::experiment
12 results on '"O. Wigger"'

1. transitions monitored by strong interactions: a new determination of the KL–KS mass difference

Author

R. Le Gac, M. Schafer, P.-R. Kettle, J. R. Fry, R. Gamet, D. Zimmerman, A. Muller, L. Sakeliou, Per Carlson, L. Tauscher, A. Ealet, P. Bargassa, D. Zavrtanik, H.-J. Gerber, P. Bloch, P. Pavlopoulos, M.B. Chertok, P. Weber, F. Blanc, Sotirios Vlachos, T. Ruf, B. L. Roberts, K. Jon-And, Marcin Wladyslaw Wolter, G. Polivka, Panagiotis Kokkas, J. Derre, A. Angelopoulos, B. Pagels, Andrej Filipcic, M. Mikuž, D. Francis, Nikolaos Manthos, Lukas A. Schaller, W. Fetscher, O. Wigger, Jeffrey Boone Miller, E. Gabathuler, R. Rickenbach, Mats Danielsson, F. Henry-Couannier, C. Thibault, M. Fidecaro, O. Behnke, A. Haselden, F. Montanet, C. Eleftheriadis, A. Benelli, F. Leimgruber, A. Schopper, C.W.E. van Eijk, T. Nakada, P.J. Hayman, Michael C. Carroll, Marc Dejardin, R.W. Hollander, I. Papadopoulos, G. Backenstoss, V. Bertin, Elie Aslanides, R. Kreuger, C. Touramanis, Igor Mandić, A. Go, G. Marel, T. Schietinger, F. Touchard, and E. Cawley

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Amplitude, CPT symmetry, High Energy Physics::Phenomenology, High Energy Physics::Experiment, Strangeness, Nuclear Experiment
Abstract

The CPLEAR set-up (modified) has been used to determine the KL–KS mass difference by a method where neutral-kaon strangeness oscillations are monitored through kaon strong interactions, rather than semileptonic decays, thus requiring no assumptions on CPT invariance for the decay amplitudes. The result, Δm=(0.5343±0.0063stat±0.0025syst)×1010ℏ/s, provides a valuable input for CPT tests.

Published
2001
Full Text
View/download PDF

2. Determination of the T- and CPT-violation parameters in the neutral-kaon system using the Bell–Steinberger relation and data from CPLEAR

Author

G. Polivka, Michael C. Carroll, D. Zavrtanik, F. Touchard, M. Wolter, E. Cawley, T. Ruf, C. Touramanis, R. Kreuger, A. Apostolakis, L. Sakeliou, C. Thibault, A. Haselden, P. Weber, G. Marel, O. Behnke, P. Bargassa, L. Tauscher, F. Henry-Couannier, E. Gabathuler, R. Rickenbach, P. Pavlopoulos, J. Derre, C. Eleftheriadis, S. Vlachos, R.W. Hollander, A. Go, F. Leimgruber, P. Carlson, V. Bertin, T. Schietinger, A. Schopper, M.B. Chertok, P.J. Hayman, B.L. Roberts, C.W.E. van Eijk, R. Le Gac, M. Mikuž, E. Aslanides, A. Ealet, Panagiotis Kokkas, J. R. Fry, M. Schafer, Mats Danielsson, I. Papadopoulos, G. Backenstoss, K. Jon-And, P. Bloch, M. Fidecaro, I. Mandić, L.A. Schaller, A. Muller, A. Benelli, D. Francis, N. Manthos, H.-J. Gerber, O. Wigger, R. Gamet, D. Zimmerman, P.-R. Kettle, Jeffrey Boone Miller, F. Blanc, B. Pagels, A. Filipčič, T. Nakada, Marc Dejardin, W. Fetscher, F. Montanet, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), CPLEAR, Lorgeril, Jocelyne, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], Unitarity, 010308 nuclear & particles physics, media_common.quotation_subject, Value (computer science), 01 natural sciences, Asymmetry, Matrix (mathematics), 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Mixing (physics), media_common
Abstract

Data from the CPLEAR experiment, together with the most recent world averages for some of the neutral-kaon parameters, were constrained with the Bell--Steinberger (or unitarity) relation, allowing the T-violation parameter $\ree$ and the CPT-violation parameter $\imd$ of the neutral-kaon mixing matrix to be determined with an increased accuracy: $\ree = (164.9 \pm 2.5)\times 10^{-5}$, $\imd = ( 2.4 \pm 5.0)\times 10^{-5}$. Moreover, the constraint allows the CPT-violation parameter for the neutral-kaon semileptonic decays, $\rey$, to be determined for the first time. The $\Delta S \neq \Delta Q$ parameters $\rexm$ and $\imxp$ are given with an increased accuracy. The quantity $\mathrm{Re}(y~+~x_-)$, which enters the T-violation CPLEAR asymmetry previously published, is determined to be $(0.2 \pm 0.3)\times 10^{-3}$. The value obtained for $\red$ is in agreement with the one resulting from a previous unconstrained fit and has a slightly smaller error.

Published
1999
Full Text
View/download PDF

3. First direct observation of time-reversal non-invariance in the neutral-kaon system

Author

Claudio Santoni, P.-R. Kettle, T. Nakada, Lukas A. Schaller, Danilo Zavrtanik, P. Bloch, R. Gamet, Sotirios Vlachos, Andrej Filipcic, A. Muller, Mats Danielsson, O. Behnke, A. Angelopoulos, V. Bertin, H.-J. Gerber, D. Zimmerman, L. Faravel, M. Fidecaro, M. Schafer, F. Leimgruber, L. Tauscher, P. Carlson, A. Schopper, P. Bargassa, E. Gabathuler, R. Rickenbach, A. Haselden, Jeffrey Boone Miller, P.J. Hayman, C. Thibault, G. Backenstoss, F. Montanet, M. Mikuž, D. Francis, Marcin Wladyslaw Wolter, A. Ealet, T. Ruf, J. Derre, P. Pavlopoulos, P. Weber, R.W. Hollander, C. Eleftheriadis, O. Wigger, R. Le Gac, M.B. Chertok, Nikolaos Manthos, A.J.P.L. Policarpo, Panagiotis Kokkas, E. Aslanides, I. Papadopoulos, K. Jon-And, Stef. Charalambous, J. R. Fry, F. Blanc, G. Polivka, B.L. Roberts, B. Pagels, W. Fetscher, C. Touramanis, F. Henry-Couannier, A. Benelli, C.W.E. van Eijk, Igor Mandić, A. Go, Marc Dejardin, Michael C. Carroll, T. Schietinger, R. Kreuger, A. Apostolakis, G. Marel, E. Cawley, and F. Touchard

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, media_common.quotation_subject, High Energy Physics::Phenomenology, Nuclear Theory, Direct observation, Charge (physics), Strangeness, Asymmetry, Decay time, High Energy Physics::Experiment, Nuclear Experiment, Particle Physics - Experiment, media_common, Lepton
Abstract

We report on the first observation of time-reversal symmetry violation through a comparison of the probabilities of K 0 transforming into K0 and K0 into K 0 as a function of the neutral-kaon eigentime t. The comparison is based on the analysis of the neutral-kaon semileptonic decays recorded in the CPLEAR experiment. There, the strangeness of the neutral kaon at time t=0 was tagged by the kaon charge in the reaction p p → K ± π ∓ K 0 ( K 0 ) at rest, whereas the strangeness of the kaon at the decay time t=τ was tagged by the lepton charge in the final state. An average decay-rate asymmetry 〈 R( K 0 t=0 → e + π − ν t=τ )−R( K 0 t=0 → e − π + ν t=τ ) R( K 0 t=0 → e + π − ν t=τ )+R( K 0 t=0 → e − π + ν t=τ ) 〉=(6.6±1.3 stat ±1.0 syst )×10 −3 was measured over the interval 1 τ S τ S , thus leading to evidence for time-reversal non-invariance.

Published
1998
Full Text
View/download PDF

4. Measurement of CP,T and CPT violation parameters in the Neutral Kaon system at CPLEAR

Author

Andrej Filipcic, D. Francis, Marko Mikuz, A. Benelli, C.W.E. van Eijk, T. Schietinger, R. Le Gac, M. Fidecaro, C. Touramanis, Claude Guyot, E. Cawley, Ph. Schune, João Carvalho, F. Montanet, Frixos A Triantis, S. Vlachos, R. Ferreira-Marques, A. Ealet, P. Bloch, Ioannis Evangelou, Ch Yèche, B. Eckart, Elie Aslanides, F. Blanc, L. Sakeliou, J. R. Fry, C. Santoni, P. Kokkas, C. Kochowski, Marcin Wladyslaw Wolter, I. Papadopoulos, A. Haselden, E. van Beveren, A. Apostolakis, J. Derre, F. Touchard, T. Ruf, B. Pagels, O. Wigger, F. Leimgruber, Igor Mandić, D. Garreta, W. Fetscher, G. Polivka, R.W. Hollander, A. Go, R. Rickenbach, R. Gamet, A. Cody, T. Alhalel, M. Carroll, H.-J. Gerber, O. Behnke, A. Soares, J. Pinto da Cunha, P.R. Kettle, L. Tauscher, C. Felder, Mats Danielsson, R. Adler, E. Machado, P. Fassnacht, E. Hubert, A.J.P.L. Policarpo, A. Schopper, F. Henry-Couannier, D. Zimmerman, P. Carlson, P.J. Hayman, P. Sanders, Marc Dejardin, M.B. Chertok, Jeffrey Boone Miller, P. Weber, E. Gabathuler, V. Bertin, A. Angelopoulos, K. Jon-And, M. Schafer, P. Bargassa, Christopher Bee, Danilo Zavrtanik, R. Kreuger, G. Marel, Michael C. Carroll, L. Faravel, Lukas A. Schaller, T. Nakada, G. Chardin, P. Paylopoulos, G. Backenstoss, Stef. Charalambous, Nikolaos Manthos, A. Liolios, C. Thibault, B. L. Roberts, and C. Eleftheriadis

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Secondary education, Large Hadron Collider, Planck scale, CPT symmetry, Information storage, symbols.namesake, symbols, High Energy Physics::Experiment, Quantum, Research method, Coherence (physics)
Abstract

The CPLEAR experiment at CERN measures the time dependent decay rate asymmetries of initially pure K0 and K 0 states to study CP,T and CPT symmetries in the neutral kaon system. The latest results on η+−, Δm and x are reported, as well as direct tests of T violation and CPT violation in K0- K 0 oscillations. Our results are consistent with CPT invariance and allow for an improved limit on the K0- K 0 mass difference. Further, a possible loss of quantum coherence of the neutral kaon system has been tested to a level near the Planck scale.

Published
1997
Full Text
View/download PDF

5. The CPLEAR-Experiment at CERN

Author

Christopher Bee, Marcin Wladyslaw Wolter, G. Chardin, J. Derre, Mats Danielsson, G. Backenstoss, Ch Yèche, R. Adler, A. Go, B. Eckart, T. Schietinger, A.J.P.L. Policarpo, A. Apostolakis, T. Alhalel, M.B. Chertok, Stef. Charalambous, A. Soares, P. Fassnacht, R. Le Gac, H.-J. Gerber, L. Faravel, D. Garreta, C. Felder, J. R. Fry, K. Jon-And, P. Bargassa, G. Polivka, Lukas A. Schaller, E. Hubert, W. Fetscher, P.R. Kettle, L. Tauscher, A. Haselden, E. Machado, Ph. Schune, D. Francis, Jeffrey Boone Miller, F. Henry-Couannier, A. Ealet, T. Ruf, O. Behnke, Claudio Santoni, Andrej Filipcic, R.W. Hollander, Marc Dejardin, Nikolaos Manthos, Danilo Zavrtanik, D. Zimmerman, Claude Guyot, F. Leimgruber, P. Pavlopoulos, A. Liolios, João Carvalho, F. Montanet, A. Schopper, M. Fidecaro, P. Weber, T. Nakada, P.J. Hayman, J. Pinto Dacunha, R. Ferreira-Marques, P. Sanders, M. Mikuz, I. Papadopoulos, R. Kreuger, Panagiotis Kokkas, O. Wigger, F. Blanc, C. Kochowski, R. Gamet, Ioannis Evangelou, G. Marel, B. Pagels, L. Sakeliou, M. Schafer, Per Carlson, Michael C. Carroll, C. Thibault, B. L. Roberts, C. Eleftheriadis, E. van Beveren, Sotirios Vlachos, F. Touchard, A. Angelopoulos, Igor Mandić, A. Cody, E. Gabathuler, R. Rickenbach, V. Bertin, Elie Aslanides, C. Touramanis, Frixos A Triantis, A. Benelli, C.W.E. van Eijk, E. Cawley, and P. Bloch

Subjects
Nuclear physics, Rest (physics), Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Large Hadron Collider, High Energy Physics::Phenomenology, Measure (physics), High Energy Physics::Experiment, Atomic and Molecular Physics, and Optics
Abstract

The CPLEAR experiment uses tagged K0 and K0 produced in pp annihilation at rest to measure CP-, T- and CPT-violation parameters in the neutral kaon system. The results of these measurements and some implications are reported.

Published
1997
Full Text
View/download PDF

6. The CPLEAR detector at CERN

Author

K. Philippoussis, H. Verweij, G. Backenstoss, P. Bloch, G. Kesseler, A. Haselden, Andrej Filipcic, P. Pavlopoulos, F. Louis, D. Damianoglou, E. Rozaki, Panagiotis Kokkas, Dominique Durand, P.-R. Kettle, M. Bonnet, F. Bal, H.U. Johner, Claude Guyot, M. Steinacher, P. Petit, T. Alhalel, R.W. Hollander, Andras Kerek, Ch Yèche, D.A. Troster, L. Faravel, M. Mikuž, D. Francis, O. Behnke, B. Eckart, Sp. Dedoussis, J. Duclos, K. Sarigiannis, C. Engster, J.P. Bard, E. Gabathuler, M. Dedieu, R. Rickenbach, T. Ruf, Mats Danielsson, R. Adler, N. Dudragne, C. Jacobs, C.P. Marin, P. Weber, Ph. Schune, E. Machado, M. Schafer, V. Bertin, P.F. Harrison, H.-J. Gerber, F. Leimgruber, A. Schopper, K. Jansson, H. Martin, Christopher Bee, L. Sacks, Ioannis Evangelou, W.G. Heyes, P. Gumplinger, M. Dodgson, R. Le Gac, A. Ealet, T. Nakada, H. Postma, E. Hazen, L. Sakeliou, R. Daniel, Ch. Bula, E. Aslanides, Nikolaos Manthos, P Harrison, P.J. Hayman, W. Albrecht, F. Nanni, M. Chardalas, Per Carlson, H. Tschopp, M.B. Chertok, A. Liolios, D. Lecouturier, Ch. Rhême, D. Garreta, J.C. Michau, W. Fetscher, C. Witzig, J. R. Fry, M. Fidecaro, P. Fassnacht, A. Benelli, C.W.E. van Eijk, Christer Fuglesang, G. S. Varner, A. Go, E. Hubert, M. Dröge, K. Jon-And, S. Tatsis, Claudio Santoni, Marc Dejardin, B.L. Roberts, Lukas A. Schaller, A. Calzas, F. Blanc, U. Mall, D. King, R. Gamet, C. Touramanis, T. Geralis, D. Guyon, C. Kochowski, N. Karkour, D. Zimmerman, T. Klados, Frixos A Triantis, Danilo Zavrtanik, F. Henry-Couannier, C. Felder, D. Barraca, B. Pagels, A. Soares, D. Linget, João Carvalho, F. Montanet, L. Tauscher, P. Dechelette, P. Tsilimigras, B. Lofstedt, K. Kontek, Marcin Wladyslaw Wolter, P. Sanders, I. Papadopoulos, J. Derre, F. Pelucchi, P. Maley, O. Wigger, B. van Koningsveld, Jeffrey Boone Miller, A.J.P.L. Policarpo, D. Geiss, T. Lawry, H. Wendler, G. Chardin, Jean-Louis Faure, J. Kern, C. Thibault, C. Eleftheriadis, Stef. Charalambous, D. Warner, G. Polivka, Michael C. Carroll, R. Kreuger, A. Apostolakis, G. Marel, I. Tsamouranis, P. Charra, Sotirios Vlachos, A. Angelopoulos, J. Pinto da Cunha, A. Onofre, T. Schietinger, J. Bennet, Igor Mandić, A. Dijksman, J.P. Vanuxem, Y. Gally, R. Ferreira-Marques, E. van Beveren, F. Touchard, J. A. P. Da Silva, A. Cody, B. Dinkespiller, E. Cawley, E. Watson, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), CPLEAR, Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), and Lorgeril, Jocelyne

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Large Hadron Collider, [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], Physics::Instrumentation and Detectors, 010308 nuclear & particles physics, Cherenkov detector, Detector, Tracking (particle physics), 7. Clean energy, 01 natural sciences, Particle identification, law.invention, Nuclear physics, Time of flight, law, Antiproton, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, Detectors and Experimental Techniques, 010306 general physics, Instrumentation
Abstract

The CPLEAR collaboration has constructed a detector at CERN for an extensive programme of CP-, T- and CPT-symmetry studies using ${\rm K}^0$ and $\bar{\rm K}^0$ produced by the annihilation of $\bar{\rm p}$'s in a hydrogen gas target. The ${\rm K}^0$ and $\bar{\rm K}^0$ are identified by their companion products of the annihilation ${\rm K}^{\pm} \pi^{\mp}$ which are tracked with multiwire proportional chambers, drift chambers and streamer tubes. Particle identification is carried out with a liquid Cherenkov detector for fast separation of pions and kaons and with scintillators which allow the measurement of time of flight and energy loss. Photons are measured with a lead/gas sampling electromagnetic calorimeter. The required antiproton annihilation modes are selected by fast online processors using the tracking chamber and particle identification information. All the detectors are mounted in a 0.44 T uniform field of an axial solenoid of diameter 2 m and length 3.6 m to form a magnetic spectrometer capable of full on-line reconstruction and selection of events. The design, operating parameters and performance of the sub-detectors are described.}

Published
1996
Full Text
View/download PDF

7. Two pion Bose-Einstein correlations in p annihilations at rest

Author

G. Chardin, Jean-Louis Faure, D. Garreta, J. Kern, G. Backenstoss, C. Thibault, C. Eleftheriadis, Ch Yèche, Francois Touchard, B. Eckart, Stef. Charalambous, Christer Fuglesang, G. Polivka, J. Pinto da Cunha, H. Postma, K. Sarigiannis, Sp. Dedoussis, R. Le Gac, J. R. Fry, P. Gumplinger, Andras Kerek, J. Duclos, M. Dejardin, A. Go, Ph. Schune, M. Schafer, T. Ruf, M. Chardalas, A. Onofre, A. Soares, R. Kreuger, A. Ealet, Kerstin Jon-And, Christopher Bee, K. Jansson, Nikolaos Manthos, P. Pavlopoulos, Ioannis Evangelou, G. S. Varner, A. Liolios, A. Schopper, B.L. Roberts, P.J. Hayman, J.P. Miller, E. van Beveren, T. Nakada, R. Garnet, Ch. Bula, P.R. Kettle, L. Tauscher, C. Witzig, V. Bertin, W. Fetscher, E. Machado, O. Wigger, Elie Aslanides, J. K. Bienlein, M. Fidecaro, M. Van den Putte, A. Alhalel, J.C. Dousse, P. Fassnacht, S. Vlachos, O. Wolter, G. Marel, J. Bennet, E. Cawley, Marko Mikuz, A. Apostolakis, Mats Danielsson, D.A. Troester, H.-J. Gerber, R. Adler, Igor Mandić, Danilo Zavrtanik, E. Gabathuler, R. Rickenbach, D. Zimmerman, E. Rozaki, W.G. Heyes, C. Kochowski, P. Carlson, R. Ferreira-Marques, B. Pagels, David Francis, C.W.E. van Eijk, P. Sanders, S. Szilagyi, Theodoros Geralis, A. Angelopoulos, P.F. Harrison, A.J.P.L. Policarpo, P. Bloch, J. Derre, Panagiotis Kokkas, F. Pelucchi, P. Weber, C. Touramanis, R.W. Hollander, Frixos A Triantis, T. Lawry, L.A. Schaller, Claudio Santoni, Andrej Filipcic, H.U. Johner, João Carvalho, F. Montanet, Claude Guyot, C. Felder, M. Dodgson, P. Maley, L. Sakeliou, L. Faravel, and L. Sacks

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Pion, Large Hadron Collider, Nuclear Theory, Detector, High Energy Physics::Experiment, Bose–Einstein correlations, Multiplicity (chemistry), Nuclear Experiment
Abstract

Bose-Einstein (BE) correlations between like-sign charged pions were studied in pp annihilations at rest into four-prong events, using data taken with the CPLEAR detector at LEAR (CERN). A strong enhancement was found in the production of pairs of like-sign pions of similar momenta, with respect to the pairs of unlike-sign pions. The observed BE- enhancement was used to extract the values for the strength λ of the effect and the radius r of the pion emitting source. The extracted value of λ >l is of relevant importance and clearly does not depend on the assumed parametrization of the correlation function. The influence of the normalization and fitting procedure, the detector resolution, the resonances production and decay and the neutral-pion multiplicity cuts, on the size of the pion source and the strength of the effect was investigated.

Published
1993
Full Text
View/download PDF

8. Pion Correlations and Resonance Effects in ppbar Annihilation to 4pi0 at Rest

Author

P. Weber, O. Kortner, V.E. Markushin, M.P. Locher, and O. Wigger

Subjects
Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Resonance, FOS: Physical sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Pion, Pi, Invariant mass, High Energy Physics::Experiment, Invariant (mathematics), Nuclear Experiment, Engineering (miscellaneous), Particle Physics - Experiment
Abstract

We study pi0pi0 correlations in the exclusive reaction ppbar -> 4pi0 at rest with complete reconstruction of the kinematics for each event. The inclusive distribution shows a dip at small invariant mass of the pion pair while a small enhancement in the double differential distribution is observed for small invariant masses of both pion pairs. Dynamical models with resonances in the final state are shown to be consistent with the data while the stochastic HBT mechanism is not supported by the present findings., 17 pages, 12 figures

Published
2002

9. A determination of the CP violation parameter eta(+-) from the decay of strangeness-tagged neutral kaons

Author

T. Nakada, R. Le Gac, E. Aslanides, M. Wolter, T. Ruf, J. R. Fry, E. Cawley, C. Thibault, A. Haselden, A. Muller, V. Bertin, A. Ealet, R. Kreuger, R.W. Hollander, M. Schafer, H.-J. Gerber, F. Blanc, G. Polivka, A. Apostolakis, G. Marel, A. Go, Marc Dejardin, P. Weber, B. Pagels, S. Vlachos, C. Eleftheriadis, Michael C. Carroll, F. Touchard, P.-R. Kettle, D. Zavrtanik, P. Pavlopoulos, Jeffrey Boone Miller, L. Tauscher, W. Fetscher, N. Manthos, A. Filipčič, O. Wigger, O. Behnke, F. Leimgruber, A. Schopper, G. Backenstoss, P.J. Hayman, A. Benelli, Panagiotis Kokkas, C.W.E. van Eijk, Ch Yèche, F. Henry-Couannier, D. Francis, I. Papadopoulos, K. Jon-And, I. Mandić, R. Gamet, C. Touramanis, M. Fidecaro, D. Zimmerman, P. Carlson, L.A. Schaller, B.L. Roberts, L. Sakeliou, P. Bargassa, J. Derre, M. Mikuž, Mats Danielsson, T. Schietinger, M.B. Chertok, E. Gabathuler, R. Rickenbach, F. Montanet, and P. Bloch

Subjects
Physics, Nuclear and High Energy Physics, Antiparticle, Particle physics, cplear, General relativity, Time evolution, Strangeness, Symmetry (physics), Nuclear physics, Antimatter, CP violation, High Energy Physics::Experiment, Particle Physics - Experiment, Coherence (physics)
Abstract

LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.

Published
1999

10. CPLEAR experiment at CERN: Measurement of CP, T and CPT in the neutral kaon system

Author

B. Eckart, C. Touramanis, J. R. Fry, Jeffrey Boone Miller, F. Blanc, Mats Danielsson, Sotirios Vlachos, T. Ruf, R. Adler, Frixos A Triantis, C. Kochowski, B. Pagels, L. Faravel, A. Angelopoulos, M. Mikuž, Marc Dejardin, E. Gabathuler, R. Rickenbach, O. Wigger, J. Pinto da Cunha, A. Haselden, P. Bloch, A. Benelli, C.W.E. van Eijk, A.J.P.L. Policarpo, A. Ealet, W. Fetscher, R.W. Hollander, G. Chardin, A. Muller, P. Weber, M.B. Chertok, D. Garreta, Ph. Schune, G. Backenstoss, Patrick Fassnacht, Lukas A. Schaller, F. Henry-Couannier, Stef. Charalambous, Ioannis Evangelou, Ioannis Papadopoulos, O. Behnke, M. Fidecaro, G. Polivka, R. Gamet, F. Leimgruber, Michael C. Carroll, A. Schopper, P.J. Hayman, Igor Mandić, P. Pavlopoulos, David Francis, R. Kreuger, Elie Aslanides, Claudio Santoni, C. Thibault, T. Nakada, L. Sakeliou, B. L. Roberts, C. Eleftheriadis, T. Schietinger, C. Felder, João Carvalho, Francois Touchard, C. Yeche, R. Ferreira-Marques, Panagiotis Kokkas, P.R. Kettle, L. Tauscher, Andrej Filipcic, Claude Guyot, E. Hubert, Kerstin Jon-And, Nikolaos Manthos, D. Zimmerman, A. Liolios, P. Carlson, F. Montanet, Christopher Bee, A. Go, A. Soares, P. Sanders, E. Machado, P. Bargassa, Danilo Zavrtanik, V. Bertin, M. Schafer, A. Apostolakis, R. Le Gac, Marcin Wladyslaw Wolter, E. van Beveren, J. Derre, A. Cody, H.-J. Gerber, G. Marel, E. Cawley, Lorgeril, Jocelyne, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), CPLEAR, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Semileptonic decay, Particle physics, [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], CPT symmetry, Branching fraction, media_common.quotation_subject, Nuclear Theory, High Energy Physics::Phenomenology, Strangeness, 7. Clean energy, Asymmetry, Nuclear physics, Pion, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, Invariant mass, Nuclear Experiment, media_common, Lepton
Abstract

Using strangeness tagging at production time, CPLEAR measures K0/K0 time-dependent asymmetries in pionic and semileptonic kaon decays. From those, a set of parameters describing CP, T and CPT violation in neutral kaon mixing and decay can be determined. Strangeness tagging at decay time with the lepton charge allows for time-reversal violation to be directly observed with a significance of more than three standard deviations. The precision on each of the CPT violation parameters is discussed. The mass equality of the K0 and K0 is tested within 4.×10−19 GeV.

Published
1997
Full Text
View/download PDF

11. Recent results on CP violation from the CPLEAR experiment

Author

E. Rozaki, E. Aslanides, L. Faravel, Marc Dejardin, P. Weber, Christer Fuglesang, J. Derre, Nikolaos Manthos, P Harrison, R. Le Gac, E. Machado, Ch Yèche, B. Eckart, J. Pinto da Cunha, M. Chardalas, A. Liolios, H. Postma, T. Nakada, J. Duclos, D. Zimmerman, L. Sacks, C. Bula, G. Burgun, T. Ruf, R. Ferreira-Marques, J. Bennet, E. Gabathuler, P. Maley, C. Guyot, A. Apostolakis, V. Bertin, P.-R. Kettle, G. Backenstoss, F. Pelucchi, K. Jansson, F. Montanet, H.U. Johner, P. Fassnacht, A. Schopper, P. Gumplinger, Andras Kerek, S. Szilagyi, T. Lawry, A. Onofre, P.J. Hayman, Ludwig Tauscher, C. Felder, D.A. Troester, Mats Danielsson, R. Adler, C. Witzig, W. Fetscher, J.C. Dousse, T. Alhalel, O. Wigger, Ioannis Evangelou, C.W.E. van Eijk, M. W. Wolter, Theodoros Geralis, L. Sakeliou, A. Go, H.-J. Gerber, J. K. Bienlein, F. Touchard, Per Carlson, C. Touramanis, E. Cawley, C. Kochowski, Philippe Bloch, Frixos A Triantis, W.G. Heyes, A. Ealet, B. Pagels, J. Kern, R.W. Hollander, S. Dedoussis, David Francis, Ph. Schune, K. Jon-And, M. Mikuz, I. Mandić, Jeffrey Boone Miller, Sotirios Vlachos, M. Schafer, R. Gamet, A. Angelopoulos, L.A. Schaller, R. Kreuger, Claudio Santoni, G. Marel, A. Filipčič, João Carvalho, Danilo Zavrtanik, P. Sanders, S. Charalambous, A.J.P.L. Policarpo, G. Varner, M. Dodgson, C. Thibault, C. Eleftheriadis, Jean-Louis Faure, D. Garreta, G. Polivka, R.L. Roberts, K. Sarigiannis, J. R. Fry, P. Pavlopoulos, M. Van den Putte, Christopher Bee, R. Rickenbach, M. Fidecaro, Panagiotis Kokkas, Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Morales A., CPLEAR, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Antiparticle, Meson, 010308 nuclear & particles physics, Strangeness, 7. Clean energy, 01 natural sciences, Atomic and Molecular Physics, and Optics, Nuclear physics, Particle decay, Pair production, Pion, Antimatter, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], CP violation, High Energy Physics::Experiment, 010306 general physics
Abstract

The CPLEAR experiment is aiming at precise CP violation tests using initially pure K0- and K0BAR beams from the intense source provided by the annihilation of the LEAR pBAR-beam in hydrogen. The strangeness tagging efficiency and the systematic errors have been studied and found to be in agreement with the design specifications. The measurement of the differential time asymmetry of the pi+pi- decays allowed the direct observation of differences in the decay rates of particles and antiparticles.The CP violating parameters were determined as \eta+/-\ = (2.32 +/- 0.14) . 10(-3) and phi+/- = 42.3-degrees +/- 4.4-degrees. First results in the reconstruction and analysis of the neutral kaon decays into two neutral pions and the K(e)3 decay are presented. Nuclear Physics B

Published
1992

12. A determination of the CPT violation parameter Re(δ)from the semileptonic decay of strangeness-tagged neutral kaons

Author

A. Angelopoulos, A. Apostolakis, E. Aslanides, G. Backenstoss, P. Bargassa, O. Behnke, A. Benelli, V. Bertin, F. Blanc, P. Bloch, P. Carlson, M. Carroll, E. Cawley, M.B. Chertok, M. Danielsson, M. Dejardin, J. Derre, A. Ealet, C. Eleftheriadis, L. Faravel, W. Fetscher, M. Fidecaro, A. Filipčič, D. Francis, J. Fry, E. Gabathuler, R. Gamet, H.-J. Gerber, A. Go, A. Haselden, P.J. Hayman, F. Henry-Couannier, R.W. Hollander, K. Jon-And, P.-R. Kettle, P. Kokkas, R. Kreuger, R. Le Gac, F. Leimgruber, I. Mandić, N. Manthos, G. Marel, M. Mikuž, J. Miller, F. Montanet, A. Muller, T. Nakada, B. Pagels, I. Papadopoulos, P. Pavlopoulos, G. Polivka, R. Rickenbach, B.L. Roberts, T. Ruf, M. Schäfer, L.A. Schaller, T. Schietinger, A. Schopper, L. Tauscher, C. Thibault, F. Touchard, C. Touramanis, C.W.E. Van Eijk, S. Vlachos, P. Weber, O. Wigger, M. Wolter, D. Zavrtanik, and D. Zimmerman

Subjects
Physics, Semileptonic decay, Nuclear physics, Nuclear and High Energy Physics, Decay time, Particle physics, Zero (complex analysis), High Energy Physics::Experiment, Production (computer science), Strangeness, Full sample, Particle Physics - Experiment, Order of magnitude
Abstract

We have improved by two orders of magnitude the limit currently available for the CPT violation parameter \red . To this purpose we have analyzed the full sample of neutral-kaon decays to \semi\ recorded in the CPLEAR experiment, where the strangeness of the neutral kaons was tagged at production and decay time. An appropriate function of the measured decay rates, including information from the analysis of \pip\pim\ decay channel, gives directly \red . The result $\red = (3.0 \pm 3.3_\mathrm{{stat}} \pm 0.6_\mathrm{{syst}}) \times 10^{-4}$ is compatible with zero. Values for the parameters $\imd$, $\rexm$ and $\imxp$ were also obtained.

Catalog

Books, media, physical & digital resources
See catalog results