The Department of Physics is seeking to recruit a Doctoral Researcher in Optical and Chemical Characterisation of Slow Liquid Scintillators for Neutrinoless Double Beta Decay and Rare-Event Searches, starting 1 January 2027, or as soon as possible thereafter, for a period of three and a half years. The position is fixed-term, as it is expected to lead to the completion of the doctoral thesis.
The position is part of the Academy Research Fellowship project "Bridging Detector and Nuclear Physics for Next-Generation Neutrinoless Double Beta Decay with Slow Liquid Scintillators" (PI: Dr. Mariia Fedkevych, Research Council of Finland, 2026–2030). The project aims to establish the experimental and theoretical foundations for a future large-scale slow Liquid Scintillator (LS) detector capable of searching for neutrinoless double beta decay (0νββ) — a rare nuclear process that, if observed, would prove that neutrinos are their own antiparticles and help to explain the origin of the matter–antimatter asymmetry of the Universe. With slow LS, it is possible to achieve Cherenkov–scintillation (C/S) separation by chemically tuning the emission-time profile of the scintillator, obtaining both calorimetric and topological information within a scalable medium suitable for tonne-scale rare-event experiments.
The doctoral researcher will be the main researcher responsible for the optical and chemical characterization work package of the project, which focuses on metal-loaded slow LS formulations (Mo, Te, Se) as candidates for isotope-loaded detectors. The work is conducted in close collaborations with our international collaborators in Johannes Gutenberg University Mainz and University of Padova, where the doctoral researcher will spend a research stay of approximately three months for advanced laboratory measurements.
The main tasks of the doctoral researcher include:
- synthesis and preparation of slow-LS samples with varying metal-organic dopant concentrations;
- measurement of optical properties (absorption and emission spectra, decay-time constants, attenuation lengths) using spectrophotometry and time-correlated single-photon counting (TCSPC);
- evaluation of chemical compatibility, long-term stability, and purification efficiency;
- building a database of validated optical parameters. This database will serve as direct input to the Geant4-based optical simulations and ML-based event reconstruction and classification tools being developed within the broader project, linking the doctoral researcher's experimental work to the detector simulation and data analysis efforts.
The student will also have an opportunity to participate in in-beam characterization campaigns at INFN Legnaro National Laboratory (LNL, Italy) and contribute to scientific publications, project reports and scientific events.
Who should apply
We are looking for a motivated candidate with a strong background in physics and an interest in experimental detector research and development work at the intersection of particle physics, nuclear physics, and optical chemistry. Applicants should hold, or be close to completing, a Master’s degree in physics or a related field.
The following qualifications are required:
- good experimental hands-on skills and interest in laboratory work;
- basic knowledge of scientific programming (Python, C++, or similar);
- good written and spoken English;
- interest in international collaboration and willingness to travel for research visits and beam campaigns.
The following skills and experience are considered advantageous for the position:
- experience in optical spectroscopy, photon detection, or scintillator characterization;
- experience in a laboratory environment involving chemical handling or detector instrumentation;
- experience with data analysis;
- familiarity with particle physics simulation tools (Geant4, ROOT) or machine learning methods.
The tasks of a Doctoral Researcher focus on research aiming at the completion of a doctoral thesis, doctoral studies, assisting teaching tasks, and other related tasks to these. The duties, qualification requirements, and the language skills of Doctoral Researchers are stipulated by the University of Jyväskylä Regulations and language skills guidelines (Doctoral Students). In addition, the Doctoral Researcher must have a permission for post-graduate studies at the University of Jyväskylä. After selection, the selected person must apply for postgraduate study rights through a separate application procedure from the Faculty of Mathematics and Science.
What we offer
Come to Jyväskylä, Finland, and join our vibrant and inspiring community!
At the University of Jyväskylä, you will be a valued member of our community with a unique opportunity to contribute to international research. You will become part of our international and multidisciplinary community that prioritizes the wellbeing of each individual. Our lively campus provides excellent opportunities for maintaining an active and healthy lifestyle.
Finland, named the world’s happiest country for consecutive years since 2018, offers a high standard of living with free education (also in English), affordable childcare, generous family benefits, and comprehensive healthcare. Work–life balance is highly valued in Finland, and employees enjoy four to six weeks of annual holiday. Jyväskylä is located in central Finland, just three hours by train from the capital Helsinki. Part of the Finnish Lakeland, the city offers easy access to nature and a range of outdoor, sports and exercise activities. As a major centre of education with a large student population, it also features a vibrant cultural scene. For more information about the University of Jyväskylä, the city of Jyväskylä, and living in Finland, see the University's International Staff Guide.
Salaries are based on job demands and employees’ performance following the Finnish University Salary System. The salary for a Doctoral Researcher is determined based on the task-specific demand level 2–4 for teaching and research staff. The starting salary will be approximately 2500 €/month (gross income). A holiday bonus is paid to all employees. With progress of thesis work, the salary will be revised in accordance with the Collective Agreement of Finnish Education Employers. A trial period of six months will be used in the beginning of the employment.
We offer good working conditions for researchers and promote the principles of HR Excellence in Research, HRS4R. The Human Resources Strategy for Researchers (HRS4R) is based on the values of the European Charter for Researchers & The Code of Conduct for the Recruitment of Researchers (Charter & Code). JYU is committed to fairness, consistency and transparency in selection decisions, and undertakes the recommendations for the responsible evaluation of a researcher in Finland. JYU has signed the DORA Declaration. By signing the agreement, JYU is committed to complying with the CoARA principles.
How to apply?
The application documents that should be included in English and in PDF format:
- A Curriculum vitae, composed according to good scientific practice and considering the template for researcher´s curriculum vitae by The Finnish Advisory Board on Research Integrity.
- A short and free-form motivation/cover letter (max 2 pages), including your research interests, career goals and previous experience and merits in relation to the qualifications for this position.
- Degree certificate (highest degree).
We look forward to receiving your application in our recruitment system by September 30, 2026.
For further information, please contact Academy Research Fellows, Dr. Mariia Fedkevych ([email protected]) or Dr. Kai Loo ([email protected]).
Our application process is transparent, professional and international. We communicate openly with the applicants throughout the recruitment process. We value equality and diversity in our work community and encourage qualified applicants to apply for this position.
