Nov 25 – 27, 2013
Europe/Zurich timezone

WITCH, a Penning Trap Experiment for Weak Interaction Studies

Nov 25, 2013, 5:30 PM
The Globe (CERN)

The Globe



Tomica Porobic (Katholieke Universiteit Leuven (BE))


One of the goals of precision measurements in nuclear beta decay is the search for deviations from the Standard Model that would point to new physics. Within the Standard Model, beta decay is described by the V-A theory but exotic contributions are experimentally not excluded with high precision. The primary aim of the WITCH experiment [1] at the ISOLDE/CERN facility is the precise determination of the beta-neutrino angular correlation coefficient, a, which is in the case of 35 Ar sensitive to a possible scalar contribution. For that purpose, a scattering-free source consisting of two Penning traps is combined with a MAC-E retardation spectrometer to probe the energy of recoiling daughter nuclei. The first daughter recoil energy spectrum was obtained in June 2011 in the decay of 35 Ar, allowing for a first albeit still crude determination of a [2]. After significant upgrades of the system, an online run in November 2012 resulted in data of much higher quality. Presently, this dataset is being analyzed. This contribution will focus on recent results and outlook of the WITCH experiment.

Primary author

Tomica Porobic (Katholieke Universiteit Leuven (BE))


Andreas Knecht (Paul Scherrer Institut) Claire Couratin (LPC-Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, Caen, France) Dalibor Zakoucky (Acad. of Sciences of the Czech Rep. (CZ)) Etienne Lienard (U) Ferenc Glück (K) Gilles Ban (LPC-Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, Caen, France) Marcus Beck (WWU Muenster) Martin Breitenfeldt (Katholieke Universiteit Leuven (BE)) Michael Tandecki (TRIUMF (CA)) Nathal Severijns (Katholieke Universiteit Leuven (BE)) Paul Finlay (Katholieke Universiteit Leuven (BE)) Simon Van Gorp (Inst. of Physical and Chemical Research (JP)) Soti Gergely (Katholieke Universiteit Leuven (BE)) Valentin Kozlov (KIT - Karlsruhe Institute of Technology (DE)) Xavier Fabian (LPC-Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, Caen, France) Xavier Flechard (LPC-Caen, ENSICAEN, Université de Caen, CNRS/IN2P3, Caen, France)

Presentation materials