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Research orientated towards the liquid-phase chemistry of homologues of the SuperHeavy Elements (SHEs) has been carried out at the Department of Nuclear Chemistry, Czech Technical University (CTU) in Prague in the recent couple of years. As a part of this research, a versatile apparatus for on-line aqueous chemistry of SHEs and their homologues is under development. One of the key features of the apparatus is the direct dissolution of radionuclide-carrying aerosols from a gas phase into an aqueous phase. In this work we describe coupling of the Particle-Into-Liquid Sampler (PILS), originally developed as a sampling system for the determination of aerosol composition by ion chromatography, with the Gas-Jet Transport (GJT) system that delivers cyclotron-produced Nuclear Reaction Products (NRPs) from a Recoil-Transfer Chamber (RTC) to the laboratory. The NRPs delivered to the laboratory are in the form of species adsorbed onto the surface of solid KCl aerosol particulates (adsorption takes place in the RTC) and such a mixed phase must be promptly and effectively transferred into a stream of an aqueous phase, in order to account for extreme instability and scarcity of a superheavy element. Compared to systems that have been used for this purpose in the past, the experimental layout of PILS-GJT turned out to be very promising, as its pilot test provided sufficient PILS efficiencies (40%–58%) and a very high gas-liquid (V/V) mixing ratio (up to 5800). These parameters also make the system suitable for future coupling with various microfluidic chemistry systems. • Direct gas-into-liquid dissolution of solid aerosol particulates. • Gas-jet transport system coupling with Particle Into Liquid Sampler. • Apparatus for aqueous chemistry of homologues of superheavy elements. [ABSTRACT FROM AUTHOR]

A new M odul A r R obotic G as-jet targ E t (MARGE) system for chemistry studies with homologues of SuperHeavy Elements (SHEs) was designed, constructed, and successfully tested on a beam line at the U-120M accelerator in NPI in Řež, near Prague. The installation of the MARGE system represents an important milestone in research in the field of homologues of SHEs in the Czech Republic. The MARGE system utilizes a robotic target switching mechanism that is remotely controlled from the laboratory. A significant advantage of this functionality is that targets can be switched without personnel having to enter the cyclotron vault, which greatly reduces the radiation exposure of the personnel, as well as prevents long delays due to the necessary cool-down time. The MARGE system is completely modular, allowing for easy upgrades or maintenance. One of the modules houses a new four-pole beam position monitor, which allows for more precise ion beam focusing and on-line diagnostics, when compared with the previous circular one-pole design. The heart of the MARGE system, the Recoil-Transfer Chamber (RTC) module, is designed as a standalone building block with the possibility of stacking multiple RTC modules. In this way, the residual beam exiting the first module can be used to produce radionuclides in a second RTC module, thus enabling the simultaneous collection and transport of atoms recoiling from more than one target foil. The system was tested during two experimental campaigns in spring and autumn of 2021. This included an optimization of the transport yield of prepared radionuclides, and a measurement of the cross sections of the following reactions: 197Au (3He, 6n) 194m Tl, 165Ho (3He, 5n) 163Tm, nat Pd (3He, xn) 104Cd, and nat Pd (3He, yn) 105Cd. The transport yield reached during the pilot test was 38 ± 2%. The performance of the system, comprising two stacked RTC modules, was verified during the third campaign in autumn of 2022. • Modular robotic cyclotron-target switching system. • Recoil-transfer chamber and gas-jet transport system for chemistry of homologues of superheavy elements. • Relative measurement of cross sections. [ABSTRACT FROM AUTHOR]