Mu3e Experiment

Search for the forbidden decay
\mu^+ \to e^+ e^+ e^-

The Mu3e experiment is a new search for the lepton-flavour violating decay of a positive muon into two positrons and one electron.

Current news

22. May 2018


Ann-Kathrin Perrevoort successfully defends her PhD thesis on the sensitivity of the Mu3e experiment for new physics and pixel frontend firmware.

Ann-Kathrin Perrevoort studied the sensitivity of the Mu3e experiment for the main search channel using an effective field theory approach and also simulated the performance for searches for two-body decays of the muon and electron-positron resonances. In addition she contributed a core piece of the pixel front-end firmware, namely the real-time time sorting of hits. The thesis is available here

28. March 2018


Zachary Hodge successfully defends his PhD thesis on the Mu3e beam line design and monitoring.

Zachary Hodge made extensive simulations for the Mu3e muon beam line at PSI, including some upgrade of the muon target E at PSI, which is supposed to improve the muon beam rate significantly. He co-developed a monitoring scheme using a scintillating target and a CCD camera for beam characterization and monitoring.

1. March 2018


Meeting on Mu3e detector integration in Wengen

We spent four days in Wengen, Switzerland going over the details of the Mu3e detector integration and discussing the procedures for producing the sub-detectors. Safety, powering, cooling, electronics and readout were also among the topics. Some photos (also of the breaks in the snow) in the Picture gallery.

14. February 2018

Review of Mu3e at PSI

Mu3e has passed a detailed review at the PSI proton accelerator users meeting. Beam time in 2018 was granted for tests of the timing and pixel detectors as well as for further development of the compact muon beam line (CMBL).

27. October 2017


Dorothea vom Bruch successfully defends her Ph.D. thesis on the Mu3e filter farm and MuPix timing behaviour

Dorothea vom Bruch developed and implemented the algorithms for the Mu3e filter farm, showing that just 12 PCs with powerful GPUs are sufficient to reduce over 10 Gbyte/s of data to manageable levels. She also performed detailed studies of the position dependent timing behaviour of the MuPix7 HV-MAPS prototype. She has now successfully defended her thesis in Heidelberg. The thesis is available here.

3. October 2017


First MuPix8 beam test at DESY

We are testing our new large sensor chip, the MuPix8, in the electron beam at DESY, Hamburg. One of the high resolution EUDET telescopes serves as a reference for efficiency and resolution measurements. Have a look at the picture gallery.

27. September 2017


Collaboration meeting in Mainz and new collaborators

In a two day meeting in Mainz we had the pleasure of welcoming four new institutes, namely the universities of Liverpool, Oxford and Bristol as well as University College London to the collaboration. We also discussed progress on all subdetectors and a variety of integration issues.

1. September 2017


MuPix8, our first large sensor, has arrived

We have just received first samples of the MuPix8 chip from the foundry. This is our first large (20mm x 10mm) pixel sensor prototype and a big step on the way to building the Mu3e tracking detector. The prototype will now be thoroughly tested in the labs in Karlsruhe and Heidelberg and will also soon see first beam at DESY in Hamburg, PSI and MAMI in Mainz.

11. August 2017


Felix Berg successfully defends his Ph.D. thesis on the Compact Muon Beam Line (CMBL) for Mu3e

Felix Berg has developed a full simulation of the high intensity, compact muon beam line for Mu3e. Beam tests he performed in the piE5 area have validated his simulations and established the beam setup for phase I of Mu3e. He has successfully defended his thesis at ETH Zürich. The thesis is available here.

13. February 2017


Meeting on future directions with Mu3e in Wengen

We spent four days in Wengen, Switzerland, discussing ideas for physics with the Mu3e apparatus beyond the search for the lepton-flavour violating decay of the muon to three electrons. Collaboration members and theorists presented new ideas for future measurements with the high acceptance, high resolution Mu3e spectrometer using high intensity muon and pion beams at PSI. Technical challenges and promising R&D directions related to high-intensity data taking were also discussed in detail. Picture gallery.
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