1) Construction of optical atomic clocks
At the FAMO National Laboratory at the NCU Institute of Physics in Toruń, a unique system of two optical clocks using ultracold strontium atoms in an optical lattice was constructed and launched. This is the result of a long-term FAMO KL research program and the culmination of the project “Construction of a Polish Optical Atomic Clock (POZA)” coordinated by the group of Professor Czesław Radzewicz from the University of Warsaw and implemented jointly by the groups of Professors Wojciech Gawlik and Jerzy Zachorowski from the Jagiellonian University and researchers from the NCU Institute of Physics.
These clocks are currently the most accurate measuring instruments and frequency standards in the country. Only the most developed countries in the world have devices of this type and similar accuracy. The clocks operating in Toruń enabled the world’s most accurate direct measurement of the clock transition frequency 1S0–3P0 in the bosonic isotope 88Sr [P. Morzyński et al., Scientific Reports 5 (2015), 17495-17499]. This achievement was the beginning of ultrahigh resolution spectroscopy (of the order of 10-17) in Poland. The constructed optical clocks were also used in dark matter studies and, for the first time in the world, as a frequency reference for a radio telescope within the VLBI network during measurements at the Astronomical Observatory in Piwnice. Our optical atomic clocks are used in many international scientific projects, financed from both European and Polish sources. Examples include physics projects within the H2020 Quantum Flagship initiative or metrology projects in consortia of the European Association of National Metrology Institutes (EURAMET).
2) Development of a new method for searching for dark matter
Scientists from the Institute of Physics (NCU) have developed an innovative research tool that gives a real chance of detecting dark matter in the form of topological defects and conducted the first experiment of this type, providing a limit on the strength of the coupling of hypothetical dark matter with the fields of the standard model. Developing experimental techniques oriented to go beyond the standard model is crucial for the development of physics, because it can help solve the most fundamental problems of modern science, such as the structure of dark matter, the variability of physical constants or the unification of the theory of gravity and the standard model. Scientists have broken another barrier between ultra-precise optical metrology and astronomy, thus opening the way to astronomical observations of a completely new type. This approach makes it possible to easily synchronize currently operating optical atomic clocks in different countries, which will enable the creation of a global observatory listening for the presence of topological defects in dark matter. This prospect is met with great interest on an international scale, and the result itself has been published [P. Wcisło et al., Nature Astronomy 1 (2016), 0009/1-6]. It should be emphasized that this achievement (starting from the development of the concept, through the construction of the apparatus and carrying out the measurement, to the analysis and interpretation of the data) was obtained in its entirety by researchers from the Institute of Physics, NCU.
4) SOCT in human eye research
Spectral Optical Coherence Tomography (SOCT) is a cutting-edge imaging technique widely used today to capture detailed pictures of the internal structures of the human eye. The concept was first described in 1995, and just four years later, physicists from Toruń, Poland, built the world’s first SOCT device. A major milestone came in 2002 when images of the tissues of a healthy volunteer’s human eye were successfully produced. SOCT proved to be more sensitive than earlier optical tomography methods, delivering higher-quality images. The technology continued to improve, and by 2004, physicists at the Faculty of Physics, Astronomy, and Informatics (WFAiIS) in Toruń developed a clinical prototype that set the standard for the world’s first commercial SOCT tomograph. In 2006, the Polish company Optopol launched the Copernicus SOCT, the first high-speed SOCT device, and by 2007, it had captured 20% of the global market. According to Poland’s Ministry of Economy, the spectral OCT tomograph is one of three, alongside graphene and infrared photodetectors, “Polish photonic products that have achieved a world-class level and commercial success on the global market”.
5) Studies of world cultural heritage paintings using optical coherence tomography
In the years 2009-2014 a group of scientists form the Institute of Physics and from the Institute for the Study, Conservation and Restoration of Cultural Heritage, Faculty of Fine Arts, both of Nicolaus Copernicus University, working in consortium 21 partners of the project CHARISMA of EU 7th Framework Programme developed specialised, portable very high resolution optical coherence tomograph (OCT) designed especially for non-invasive examination of cultural heritage objects. Inspection of such objects is always carried out at the invitation of the object’s owner or curator and contributes to better understanding of the structure of the work of art and to determination of its state of preservation. It is necessary, among others, for proper planning of conservation and restoration campaign. Without this knowledge such treatments would be burdened with a high risk of damage to the object and therefore are necessary especially in case of most valuable artworks. It should be emphasized that the group headed by prof. Piotr Targowski and comprising researchers form the Institute of Physics and from the Institute for the Study, Conservation and Restoration of Cultural Heritage as one of the few in the word has access to most valuable and best-known works of art. Among others, due to co-operation with Opficio delle Pietre Dure in Florence, it was possible to examine the monumental “Adoration of the Magi” by Leonardo da Vinci from the collection of Uffizi Gallery in Florence and also an attributed to Leonardo and his studio “The Landsdowne Virgin of the Yarnwinder” from a private collection. In 2013, by invitation of Royal Institute for Cultural Heritage (KIK/IRPA) in Brussels, panels from “Ghent Altarpiece” by van Eyck brothers was examined with OCT. In 2014 again for Opificio and for Galleria Nazionale delle Marche, Urbino “The Portrait of a Young Woman”, also known as “La Muta”, by Raphael was investigated. In 2016, by invitation of Cultural Heritage Agency of the Netherlands (RCE) the “Historical Painting 1626” by Rembrandt Harmenszoon van Rijn from the collection of Rijksmuseum in Amsterdam and famous “The Sunflowers” by Vincent van Gogh from van Gogh Museum were examined. This last session was a part of the broad examination campaign of this picture, carried out under Horison 2020 IPERION CH project, within MOLAB offer. In addition to the NCU (OCT) also University of Amsterdam and RCE (restoration issues), University of Antwerp (MaXRF), and The Università degli Studi di Perugia (FTIR) were involved. Among artworks in Polish collections the most precious objects examined were “The Last Judgment” by Hans Memling from the National Museum in Gdańsk and “The Passion of Christ” from the St. James Church in Toruń.
OCT tomography is under development in the Institute of Physics NCU mostly for medicine diagnostic, especially in ophthalmology. When applied for examination of works of art, in the case of easel paintings it enables the assessment of the condition, thickness and number of varnish layers, the analysis of the structure of glaze layers and the precise identification of the range of former restoration interventions. It can also be used for precise evaluation of the effectiveness and safety of planned restoration treatments such as removal of unwanted layers of varnishes and overpaintings. In addition to easel paintings, OCT is also used to study, among others, historic glass, amber artwork, glaze layers on ceramic and for inspection of other transparent coatings like furniture polish and lacquer.
Prof. Targowski is a President of the Governing Board of Polish Research Consortium for Heritage Science E-RIHS.PL
6) Discovery of extrasolar planetary systems
With the discovery of the first planetary system around other star than our own Sun by the NCU graduate Aleksander Wolszczan in 1992 a new research area in astronomy was opened: search for and characterization of extrasolar planetary systems. Toruń Center for Astronomy is an active player in this area from the very beginning.
Krzysztof Goździewski and Cezary Migaszewski presented numerous papers devoted to dynamical analysis of extrasolar multiplanetary systems. Their papers presenting detailed studies of HD 82943 [Goździewski & Maciejewski 2001, ApJ 563, L81] or HR 8799 [Goździewski & Migaszewski 2009, MNRAS, 397, 14; 2014, MNRAS 440, 3140] may serve as excellent examples of their work.
Andrzej Niedzielski and his coworkers, in collaboration with Aleksander Wolszczan (PennState), are authors of a series of papers announcing discovery of around 30 extrasolar planetary systems (and counting), mainly around evolved stars [e.g. Niedzielski et al. 2007, ApJ, 669, 1534; 2009 ApJ, 707, 768; 2015, A&A, 573, 36] within the PennState-Toruń Planet Search. A detailed characteristics of the nearly thousand stars searched for planets within this project was also presented [cf. Deka-Szymankiewicz, Niedzielski et al. 2018 A&A 615, 31 and references therein]. This project resulted in many theses as well.
Gracjan Maciejewski is exploiting the novel technique of transit timing variation (TTV) in search for additional component in known transiting exoplanet systems. The most spectacular result so far are the spinning-down of WASP-12 b planet orbit through tidal interactions [Maciejewski et al. 2016, A&A 588, L6] and detailed activity study in WASP-10 [Maciejewski et al. 2011, MNRAS 411, 1204].
7) Discovery of periodic and alternating flares of the methanol and water masers in high-mass star-forming regions
A team of radio astronomers including Marian Szymczak, Anna Bartkiewicz, Marcin Gawroński, Paweł Wolak, and Mateusz Olech has discovered 34.4 day periodic flares of the 6.7 GHz methanol and 22 GHz water masers coupled in mutually exclusive pattern in one of the star forming regions monitored using the Torun 32 m dish. The methanol maser flares could be triggered by infrared photons which flux is modulated by cyclic accretion instabilities in a cicrcumstellar of protobinary disc. The accretion rate in a binary system may vary with the orbital phase switching between the methanol and water maser favouring conditions. This discovery is a part of the unique systematic, long-term monitoring of cosmic masers done at the NCU.
Publications:
M. Szymczak et al., Monthly Notices of the Royal Astronomical Society 459 (2016), L56-L60
M. Szymczak et al., Monthly Notices of the Royal Astronomical Society 474 (2018), 219-253