Doctoral Researcher in Optical and Chemical Characterization of Slow Liquid Scintillators for Neutrinoless Double Beta Decay and Rare-Event Searches University of Jyväskylä in Finland

The Department of Physics at the University of Jyväskylä in Finland is recruiting a Doctoral Researcher for a project on the optical and chemical characterization of slow liquid scintillators for neutrinoless double beta decay and other rare-event searches. The position starts on 1 January 2027, or as soon as possible thereafter, and is fixed-term for three and a half years, with the expectation that it leads to the completion of a doctoral thesis.

This doctoral project is embedded in the Academy Research Fellowship project Bridging Detector and Nuclear Physics for Next-Generation Neutrinoless Double Beta Decay with Slow Liquid Scintillators, led by Dr. Mariia Fedkevych and funded by the Research Council of Finland for 2026–2030. The broader scientific goal is to develop the foundations for a future large-scale slow liquid scintillator detector that can search for neutrinoless double beta decay, a rare nuclear process with major implications for neutrino physics and the origin of the matter–antimatter asymmetry of the Universe.

The doctoral researcher will lead the optical and chemical characterization work package, focusing on metal-loaded slow liquid scintillator formulations using isotopes such as Mo, Te, and Se. The work includes sample synthesis and preparation, optical measurements such as absorption and emission spectra, decay-time constants and attenuation lengths, and chemical studies on compatibility, long-term stability, and purification efficiency. Measurements will use methods such as spectrophotometry and time-correlated single-photon counting (TCSPC), and the resulting validated optical parameters will feed directly into Geant4-based optical simulations and machine-learning-based event reconstruction and classification tools.

The project offers an international research environment and close collaboration with Johannes Gutenberg University Mainz and the University of Padova. The doctoral researcher will spend around three months abroad for advanced laboratory measurements and may also take part in in-beam characterization campaigns at INFN Legnaro National Laboratory in Italy. The role combines experimental detector research, optical chemistry, rare-event detector development, and data-driven analysis.

Applicants should have, or be near completion of, a Master’s degree in physics or a related field. Required skills include strong hands-on laboratory ability, basic programming knowledge in Python, C++, or similar, good spoken and written English, interest in international collaboration, and willingness to travel for research visits and beam campaigns. Helpful experience includes optical spectroscopy, photon detection, scintillator characterization, laboratory chemical handling, detector instrumentation, data analysis, and familiarity with Geant4, ROOT, or machine learning methods.

The position is located in Jyväskylä, Finland, where the University of Jyväskylä offers a supportive research community, good working conditions, and a salary starting at about 2500 €/month gross under the Finnish University Salary System, plus a holiday bonus. The university also emphasises research integrity, equality, transparency, and responsible evaluation. Candidates must have permission for postgraduate studies at the University of Jyväskylä and must apply separately for postgraduate study rights after selection.

The application deadline is 30 September 2026. Applications must be submitted in English and PDF format, including a curriculum vitae, a short motivation/cover letter, and the highest degree certificate.