Newsletter I/2026

Ten scientific projects at the Heinz Maier-Leibnitz Zentrum (MLZ) are being funded with around €7.6 million by the Federal Ministry of Research, Technology and Space (BMFTR). The funding began in January 2026 as part of the so-called ErUM-Pro programme, for a period of three years. ErUM stands for ‘Exploration of the Universe and Matter’.

NEPOMUC's 5-fold switch in the Experimental Hall. © Bernhard Ludewig, FRM II / TUM

NEPOMUC's 5-fold switch in the Experimental Hall. © Bernhard Ludewig, FRM II / TUM

Prof. Dr Christoph Hugenschmidt from Technical University of Munich (TUM) is delighted that no fewer than six projects, totalling just under €4.7 million, will benefit NEPOMUC, the world’s most intense positron source at FRM II. One project involves replacing the Anger cameras at NEPOMUC with new detectors. Thanks to them, scattered photons can be measured with three times higher spatial resolution.

The SuSpect (Surface Spectrometer) project will “measure both structure and element concentration on a single sample surface”, says Christoph Hugenschmidt.

The positron instruments in 2021 - still in the Experimental Hall. They are currently being moved to the Neutron Guide Hall East. © Bernhard Ludewig, FRM II / TUM

The positron instruments in 2021 - still in the Experimental Hall. They are currently being moved to the Neutron Guide Hall East. © Bernhard Ludewig, FRM II / TUM

Three further positron projects are being led by the University of the Bundeswehr (UniBw) Munich. One involves Dr Werner Egger developing and constructing a pulsed positron beam system (L-PLEPS), which is intended to be accessible also to industry for the investigation of defects in thin films of semiconductors and membranes.

With micrometre-level precision, the scanning positron microscope can detect defect distributions in samples. Project leader Prof. Dr Günther Dollinger from UniBW Munich explains: “Our aim is to significantly improve the resolution and performance of the scanning positron microscope.”

Positrons from NEPOMUC also play a central role in the collaborative project “PosiLac”, led by Dr Michael Mayerhofer of the UniBW Munich and Dr Robert Heine of Johannes Gutenberg University Mainz. The funding will be invested in the 3D printing of a high-frequency resonator.

Johanna Jochum und Lukas Beddrich doing instrument scientist's stuff. © Astrid Eckert, FRM II/ TUM

Johanna Jochum und Lukas Beddrich doing instrument scientist's stuff. © Astrid Eckert, FRM II/ TUM

Dr Johanna Jochum from FRM II at TUM is responsible for two of the new projects at the RESEDA neutron resonance spin echo spectrometer, with a total of 1.8 million euros. “The TIGER project aims to equip RESEDA for operation with thermal neutrons,” explains Johanna Jochum, who heads the RESEDA instrument team. The second project focuses on integrating focusing neutron optics into RESEDA particularly for small samples or measurements under pressure.

Working at ANTARES. © Bernhard Ludewig, FRM II / TUM

Working at ANTARES. © Bernhard Ludewig, FRM II / TUM

“To monitor the water level in electrolysis cells accurately, we need to examine the cell as it is operating. Thanks to a grant of €670,000, we can develop such a test setup for the instrument ANTARES explains Dr Michael Schulz, Deputy Scientific Director at FRM II. The project is led by Dr Joey Disch at the University of Freiburg.

The irradiation room of MEDAPP. © Wenzel Schürmann, FRM II/ TUM

The irradiation room of MEDAPP. © Wenzel Schürmann, FRM II/ TUM

Medical research also benefits from €500,000 funding. “We can now investigate and further develop the boron-neutron capture at the MEDAPP instrument – and thus contribute to making this form of therapy more targeted and precise,” says Dr Tobias Chemnitz, project leader and instrument scientist at MEDAPP.

Naomi Dieng (MLZ)

LaDiff is our new triple-axis spectrometer with a Larmor diffraction option. We are currently in the construction phase and aim to complete the instrument in time for the arrival of neutrons.

But it is not completely new in the neutron world: The cold three axis spectrometer FLEXX from BER 1 (HZB) had been transferred to Garching to start a second life of scientific use at the MLZ.

Due to the proximity of the instrument to the visitors’ gallery and the offices in the Neutron Guide Hall West (former MIRA location), a large biological shielding is being constructed. We have just completed the stainless steel structure and are now proceeding with the lead shielding to “decorate” our steel framework.

Biological shielding of LaDiff: A layer of stainless steel, as shown in the picture, will support the lead shielding that will be installed around the instrument in the coming months.

© MLZ

A section of the neutron guide NL6, together with the LaDiff monochromator shielding in focus. Preparations for installing the biological shielding are visible on the dance floor.

© MLZ

The multianalyser unit of LaDiff consists of 31 chanels in Q, visible here. Each channel contains five analyser-detector units, resulting in a total of 155 detectors. The detector electronics are mounted on top.

© MLZ

The monochromator shielding from the FLEXX TAS instrument has been upgraded and is being reused at LaDiff, fed by the NL6 neutron guide. The new placement of the monochromator shielding at its final location has been completed, and the neutron guides’ vacuum has been successfully tested and is now ready to receive neutrons.

In parallel, and in close collaboration with our Detector Group, we have carried out tests on the multianalyser / detector array, also inherited from FLEXX. This multianalyser serves as an optional component for the secondary spectrometer, particularly useful when rapid mapping of dispersions in (Q, ω) is required by our users.

We continue working intensively to bring the project to completion and are very much looking forward to the restart!

Markos Skoulatos (MLZ)

The construction works at TOPAS are going at full steam! For the past few years, the instrument has been assembled and installed in the Neutron Guide Hall East, and will add new possibilities to the suite of the MLZ instruments by means of time-of-flight (TOF) spectroscopy with thermal neutrons. The ambitious goal for the instrument is to allow for polarization analysis, a challenging task for the TOF technique.

There is a lot going on at TOPAS. In the gallery you can see some snapshots comparing the state a year ago and today. They clearly illustrate how many components and kilometers of cables go into assembling a complex instrument. Last year the neutron choppers were installed at TOPAS, the heart of the instrument. The set of two Fermi choppers and one disc chopper rotate at high frequencies at a synchronized rate to provide neutrons with the required energy.

TOPAS gallery 01

TOPAS is situated in the center of the Neutron Guide Hall East. The view from the gallery on the back side of the instrument shows the state in late 2024. The main components were installed, and there was still plenty of free space on the top level.

© Forschungszentrum Jülich GmbH

TOPAS gallery 02

Today, many more components are installed. Starting from the bottom, we have the main pump and the chimney connection to the detector chamber. The chamber is illustrated on the colorful poster. The black electronics cabinet coordinates the work of the detector tubes. In the back, Harald is inspecting the vacuum controls of the detector chamber.

© Forschungszentrum Jülich GmbH

TOPAS gallery 03

View from ground level inside the hutch. Engineers are finalizing the installation of the vacuum housing in which the choppers and neutron guides reside. On the right is the large detector chamber, which will hold cryogenic pressure.

© Forschungszentrum Jülich GmbH

TOPAS gallery 04

The space is much more filled now. In the center we have the large shiny housing of the disc chopper, and the movable shielding to the left of it. To the right, the cryopump is mounted and connected to the evacuation pump. These are crucial elements of the vacuum system that will ensure cryogenic pressure in the detector chamber and low background measurements.

© Forschungszentrum Jülich GmbH

TOPAS gallery 05

Fermi chopper being lifted by the crane to be mounted in the neutron guide. This chopper is the last in the chopper cascade of TOPAS. It sits close to the sample and monochromatizes the neutron pulse. It is mounted in the bore situated between two sets of coils, see the brown wiring, which will be used to control the polarization direction of incoming neutrons.

© Forschungszentrum Jülich GmbH

TOPAS gallery 06

Engineers from Forschungszentrum Jülich GmbH, Marko and Andi, are performing tests of the choppers. The vacuum housing where the choppers reside was pumped to low pressure to reduce air resistance of spinning parts. The choppers were rotating at hundreds of hertz and were controlled by the software Marko is using on his laptop. There is quite a bit of electronics to control the chopper cascade, occupying two cabinets that Andi is looking into. The tests were successful! The choppers were running at full speed and could be controlled remotely. The official commissioning of the chopper cascade will be done in June 2026.

© Forschungszentrum Jülich GmbH

TOPAS gallery 07

Vladimir is testing the detector array of TOPAS. The detector control electronics are in the cabinet located on the gallery level. The detector chamber, where 288 helium tubes are mounted, is below Vladimir on the ground level.

© Forschungszentrum Jülich GmbH

TOPAS gallery 08

First picture from the TOPAS detector. The detectors were running for a few days to collect background counts and show a uniform blue picture. The helium tubes are arranged in an array that acts as a two-dimensional detector. The voltage of each tube is carefully monitored to provide optimal conditions for neutron detection. Next step is to run measurement with artificial neutron source.

© Forschungszentrum Jülich GmbH

TOPAS gallery 09

Part of the team behind TOPAS: Simon, Christoph, Achim, and Michal. A dedicated team of engineers and scientists is carrying out the detailed work of installing and testing the equipment, while coordinating the efforts of multiple engineering groups responsible for electronics, choppers, and detectors. Around 10 people are involved in the core work on TOPAS, supported by many service groups from Forschungszentrum Jülich GmbH and MLZ.

© Forschungszentrum Jülich GmbH

This year, TOPAS entered the crucial stage of cold commissioning. It involves testing the instrument’s main components without neutrons. The choppers were spun at high vacuum, which they require for high-frequency operation. Equally important, the detector tubes were tested by performing background measurements. Now we put all the components together to act as a single instrument: TOPAS. So far so good, the commissioning is going according to the established plan, and we are getting ready for hot commissioning with neutrons, when the reactor restarts.

Michal Stekiel (JCNS@MLZ)

© MLZ

© MLZ

After 26 years leading the FRM II detector group, Karl Zeitelhack entered his well-deserved retirement at the end of January.

Karl founded the FRM II detector group in 2000, having previously worked on detector development for heavy-ion physics at the TUM Physics Department just across the road. In the early years he built the group from the ground up, establishing the personnel and infrastructure that would support detector development at FRM II for decades.

Alongside this, Karl played a key role in setting up many of the first instruments at FRM II. Following the start of the reactor in 2004, he led the flux measurements from the cold source, an important milestone in commissioning the facility.

Karl Zeitelhack 1999

Karl during the installation of the HADES RICH detector at GSI Helmholtzzentrum für Schwerionenforschung at Darmstadt.

© unknown

Karl Zeitelhack 2006

Karl conducting detector test measurements at TREFF in 2006. TREF is the FRM II’s test beam line.

© FRM II/ TUM

Throughout his career, Karl worked to strengthen collaboration between detector groups worldwide, building an excellent international network that continues to this day. A central element is the International Collaboration for the Development of Neutron Detectors (ICND), which Karl chaired from its inception in 2010. The group also participated in the European FP6 and FP7 programmes for neutron detector development.

Karl Zeitelhack 2010_01

Happy faces during the installation of the SANS-1 detector bank at FRM II! (Karl: third from the left).

© FRM II/ TUM

Karl Zeitelhack 2010_02

Joint measurements at the ILL with colleagues from around the world (Karl: second from the left).

© ILL

Under his leadership, the detector group began its programme of large in-house detector production, starting with the Stress-Spec MWPC and later developing large-area curved detectors for ERWIN and DMC at PSI. Most recently, a vertically curved detector for Stress-Spec has entered production.

Karl Zeitelhack 2021

Karl during the assembly of the ERWIN detector inside the detector group cleanroom in 2021.

© MLZ

Karl Zeitelhack 2024

The Erwin detector finally installed at the instrument! Learn more about the trip from the lab to the instrument here.

© FRM II/ TUM

Karl Zeitelhack 2023

Karl (left) and Christoph Hauf (instrument scientist at FIREPOD) happily receiving delivery of detectors for the instrument!

© FRM II/ TUM

Karl said farewell to colleagues at an extremely well-attended reception, reflecting the respect and appreciation he has earned over the years. We thank Karl for his many contributions and wish him all the very best for the future.

Alan Howard (MLZ)

© private

© private

I am Noah, the new first instrument scientist for POWTEX. I will take part in its commissioning, ensure everything works when neutrons arrive, and continue advancing the AIXtal analysis suite (https://doi.org/10.5281/zenodo.15094877).

My involvement with POWTEX began with a student project on the instrument’s neutron guide about nine years ago and has stuck with me ever since. After years of theoretical work and development (https://doi.org/10.3390/qubs8040030, https://doi.org/10.18154/RWTH-2025-10487, https://doi.org/10.1107/S1600576723002819) I am thrilled to finally see the instrument actually running!

© ESS

© ESS

Hej! I am Robin and excited to have joined the neutron imaging team at MLZ as the new group leader. With a background in engineering and materials science, I bring perspectives from nine years at the University of Tennessee / ORNL and 11 years at ESS, including a five-year secondment to HZB.

I look forward to leveraging synergies on the TUM campus to advance neutron imaging and connect it more closely with scattering techniques. Looking forward to meeting y’all!

Want to know more about me? Find the list of my publications at Google Scholar.

Participants mingling. © MLZ

Participants mingling. © MLZ

232 MLZ users took up the invitation to the User Meeting in December. Not only did they have to travel to a new venue, they also found themselves in a new setup. Instead of the usual hotel, we moved to a colourful conference centre with a ping pong table! We also said goodbye to the seven parallel workshops on the first day, which meant that we were able to start with a warm welcome from the MLZ directors.

Stephan Paul (centre) with the MLZ Prize, surrounded by MLZ Directors Christian Pfleiderer (left) and Martin Müller (right). © MLZ

Stephan Paul (centre) with the MLZ Prize, surrounded by MLZ Directors Christian Pfleiderer (left) and Martin Müller (right). © MLZ

They updated the participants on the current status of FRM II in relation to the planned restart, after which they presented the 2025 MLZ award to Stephan Paul of TUM. In his awardee talk, he took the participants back to the moments immediately following the Big Bang. In the afternoon, three parallel sessions covered topics such as structural chemistry, hydrogen-metal interactions, and polymers and proteins. In the evening, a traditional Bavarian dinner ensured a good atmosphere and plenty of conversation

An attentive audience during the talks. © MLZ

An attentive audience during the talks. © MLZ

The second day began with two scientific plenary talks. Hanna Barriga (KTH Stockholm) discussed lipid nanoparticles and their characterisation. The aim is to help design these complex little helpers for drug delivery. Jasper Landman (University of Wageningen) captivated the audience with his work on the superstructures of pulse proteins.

Christian Felder presenting the evolution of data management at MLZ. © FRM II/ TUM

Christian Felder presenting the evolution of data management at MLZ. © FRM II/ TUM

The second part of the morning session was dedicated to preparations for the restart. Here, different groups presented their approaches. Manuel Suárez Anzorena (MLZ), head of the Sample Environment Group, presented the ongoing equipment tests to ensure the instruments are ready for use. Anatoly Senyshyn (MLZ) talked about the diffractometer group and their different approach. While SPODI is a well-known workhorse, ERWIN and FIREPOD will need to be commissioned. Henrich Frielinghaus (JCNS@MLZ) then described the situation with the SANS machines, which will indeed be affected by the absence of the cold source, and presented ideas on how to manage this situation. Christian Felder (JCNS@MLZ) concluded the session with a live demonstration of the new data management workflow. This involves automated data acquisition via the NICOS instrument control system, an Electronic Lab Notebook, and the option to download all data. The login and access to this workflow is realised via GhOST, which makes things much more convenient for users!

Lively discussions during the poster session. © MLZ

Lively discussions during the poster session. © MLZ

The User Meeting ended with the traditional poster session. There, it was great to finally have beer again, as the last few didn’t offer any. It created a relaxed atmosphere to talk to people and plan future collaborations.