It is with deep sadness that we inform you that on March 19, 2025, passed away
a long-time employee of the The Henryk Niewodniczański Institute of Nuclear Physics Polish Academy of Sciences in Kraków.
We express our deepest condolences to the family and loved ones.
Directors, Scientific Council and Employees
of the The Henryk Niewodniczański Institute of Nuclear Physics
Polish Academy of Sciences
The farewell will take place on March 21, at 12:30 p.m. in the chapel at the Crematorium at Wielogórska Street 16.
On March 19, 2025, we say goodbye to the dearly missed Dr. Witold Męczyński, a retired employee of the Department of Nuclear Structure at the Institute of Nuclear Physics PAS, our colleague and dear friend, and for younger generations of physicists – a dedicated mentor. Despite his exceptional cheerfulness, unwavering optimism, and unbreakable spirit, which gave him strength in his struggle with the illness he faced in recent times, today, unexpectedly for his family and friends, he has left us.
For over 40 years, Witek was associated with the experimental group of our Department, tirelessly delving into the mysteries of nuclear structure, particularly through the construction and continuous improvement of nuclear radiation detection equipment. He was the driving force behind research programs carried out in foreign institutes and accelerator laboratories, including JINR in Dubna, KFA in Jülich, LNL in Legnaro, HMI in Berlin, IRES in Strasbourg, and GSI in Darmstadt. One notable example of the devices he built is the Recoil Filter Detector (RFD), which still serves us today in gamma spectroscopy studies of nuclei produced in heavy-ion beam
reactions. 
Witek also worked on the design of Europe's largest gamma-ray spectrometer – AGATA.
He coordinated Poland’s contribution to this project and was a member of the steering committee of this collaboration. In the final years of his professional career, Witek devoted himself to developing the research infrastructure at the Cyclotron Centre Bronowice of IFJ PAN. Thanks to his vision and vast experience, the proton beam experimental hall was designed and equipped not only in accordance with the highest global standards but also with consideration for the most sophisticated needs of experimenters. We continue to benefit from his innovative solutions in the numerous experiments conducted here every day.
Knowledge and competence, but also openness and camaraderie, were the qualities that earned Witek friends among physicists all over the world. The Zakopane Conference on Nuclear Physics, organized by our Department for over half a century and often chaired by Witek, particularly benefited from these traits. The family-like atmosphere of these meetings, which he helped create, became a hallmark of the Zakopane Conferences, which remain to this day one of the most important gatherings of the global nuclear physics community.
In his final years, Witek lived in his hometown of Zamość, surrounded by his loved ones and a group of his beloved pets – cats and dogs. This time, his talents and boundless energy were channeled into the comprehensive renovation of his historic house, where we often visited, admiring his dedication and determination as a host sharing future plans for expanding this charming estate—plans which, sadly, he will no longer realize.