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The three-dimensional reconstruction of particle tracks in a time projection chamber is a challenging task that requires advanced classification and fitting algorithms. In this work, we have developed and implemented a novel algorithm based on the Random Sample Consensus Model (RANSAC). The RANSAC is used to classify tracks including pile-up, to remove uncorrelated noise hits, as well as to reconstruct the vertex of the reaction. The algorithm, developed within the Active Target Time Projection Chamber (AT-TPC) framework, was tested and validated by analyzing the 4 He+ 4 He reaction. Results, performance and quality of the proposed algorithm are presented and discussed in detail.

The Active-Target Time Projection Chamber (AT-TPC) was recently built and commissioned at the National Superconducting Cyclotron Laboratory at Michigan State University. This gas-filled detector uses an active-target design where the gas acts as both the tracking medium and the reaction target. Operating inside a 2T solenoidal magnetic field, the AT-TPC records charged particle tracks that can be reconstructed to very good energy and angular resolutions. The near- 4 π solid angle coverage and thick target of the detector are well-suited to experiments with low secondary beam intensities. In this paper, the design and instrumentation of theAT-TPC are described along with the methods used to analyze the data it produces. A simulation of the detector’s performance and some results from its commissioning with a radioactive 46 Ar beam are also presented.

The Active Target Time Projection Chamber (AT-TPC) project at the National Superconducting Cyclotron Laboratory (NSCL) is a novel Active Target designed to study nuclear reactions induced by low-intensity exotic beams. The AT-TPC acts as a tracking medium and target at the same time, providing excellent angular (1 ° ) and energy resolution (3% FWHM) and high luminosity . The AT-TPC offers a broad range of applications within the low-energy nuclear physics domain. Resonant scattering and transfer reactions are typically performed with Active Targets using beams with energies spanning from 1 to 10 A MeV and with intensities as low as 100 pps. The AT-TPC is also a promising tool for experiments where the observables of interest require higher beam energies (above 100 A MeV ). In particular, inelastic scattering reactions on light targets, where the recoil particle has a very low kinetic energy (less than 1 MeV), can be performed with such a device. In this work, we discuss aspects of the AT-TPC experimental program, focusing on experiments that leverage the outstanding capabilities this detector offers. In addition, we introduce a conceptual design for a new Time Projection Chamber detector for specific measurements of reactions using special gases as targets.

The present paper gives an overview of the status of an ongoing project aiming at the development of a fast neutron imaging system for investigating two-phase flows primarily in the context of nuclear fuel bundle development. Other potential subjects for investigations include steam explosions for severe accident research and liquid metal two-phase flows for Gen IV reactor systems. The project is carried out in the form of a feasibility study that should enable estimation of the ultimate imaging capabilities achievable. The imaging system used in the feasibility study consists of a compact, deuterium–deuterium fusion based neutron generator and dedicated imaging detectors. For the latter two promising concepts are developed in parallel: one is based on an array of plastic scintillators coupled with silicon photomultipliers, the other on a special multi-foil recoil proton converter coupled to a position sensitive charge readout using a micro pattern gas detector.

We present our studies of prostatic Zn concentration measurements, carried out in the light of a novel prostate cancer (CAP) diagnosis method proposed by us. The method is based on in vivo prostatic Zn mapping by XRF trans-rectal probe. We report on the extensive clinical studies, intended to assess the validity of the novel proposed diagnostic method. Zn content was measured in vitro in needle-biopsy samples from several hundreds of patients, and was correlated with histological findings and other patient parameters. For this purpose, a technique of absolute Zn content determination in approximately 1mm(3) fresh tissue samples by XRF was developed. The experimental details and the main clinical-evaluation results are presented. We further outline the suggested design of the XRF trans-rectal probe for an efficient in vivo detection and mapping of the Zn fluorescence radiation from the prostate through the rectal wall. Laboratory phantom studies, a preliminary design concept and its expected performance are also reported.

We briefly present the principal properties of THGEM detectors, in standard and in noble gases (Xe, Kr, Ar and Ne), and shortly discuss their potential applications in accelerator- and non-accelerator-based experiments. UV-photon imaging in RICH, tracking of ionizing particles, large-volume TPCs for rare-events, sampling elements in digital calorimetry, ionization and scintillation recording from noble-liquid detectors, X-ray and neutron radiography etc.