Phenomenology of the ppK+K−ppK^{+}K^{-} system near threshold

In this article studies of the near threshold $pp\to ppK^+K^-$ reaction conducted with the COSY-11 and the ANKE detectors are reviewed. In particular recent investigations on the $K^+K^-$ final state interaction are revisited taking into account updated cross sections of the COSY-11 experiment. These studies resulted in the new value of $K^+K^-$ effective range amounting to: $\mathrm{Re}(b_{K^{+}K^{-}}) = -0.2^{+0.8_{stat}~+0.4_{sys}}_{-0.6_{stat}~-0.4_{sys}}~\mathrm{fm}$ and $\mathrm{Im}(b_{K^{+}K^{-}}) = 1.2^{~+0.5_{stat}~+0.3_{sys}}_{~-0.3_{stat}~-0.3_{sys}}~\mathrm{fm}$. The determined real and imaginary parts of the $K^+K^-$ scattering length were estimated to be: $\left|\mathrm{Re}(a_{K^{+}K^{-}})\right| = 10^{~+17_{stat}}_{~-10_{stat}}~\mathrm{fm}$ and $\mathrm{Im}(a_{K^{+}K^{-}}) = 0^{~+37_{stat}}_{~-10_{stat}}~\mathrm{fm}$.Comment: Proceedings from the II International Symposium on Mesic Nuclei, Cracow, September 22 - 25, 201

Study of the K+K- Interaction at COSY-11

In this article we present studies of the near threshold pp-->ppK+K- reaction in view of the K+K- final state interaction. The investigations include analysis of both the low-energy K+K- invariant mass distributions measured by COSY-11 collaboration at excess energies of Q = 10 MeV and Q = 28 MeV and the near threshold excitation function for the pp-->ppK+K- reaction. As a result of these studies we have estimated the K+K- scattering length more precise compared to the previous analysis based only on the analysis of the differential cross sections.Comment: Proceedings from the MESON2010 conference ,3 pages, 3 figure

Study of the time reversal symmetry in the decay of ortho-Positronium atoms using the J-PET detector

The Jagiellonian Positron Emission Tomograph (J-PET) is a novel device based on organic scintillators being developed at Jagiellonian University in Kraków, Poland. J-PET is an axially symmetric and high acceptance scanner that can be used as a multi-purpose detector system. It is well suited to pursue tests of discrete symmetries in decays of positronium in addition to medical imaging. J-PET enables measurement of both momenta and polarization vectors of annihilation photons. The latter is a unique feature of the J-PET detector which allows study of the time reversal symmetry violation operator constructed solely from the annihilation photons momenta before and after scattering within the detector

Performance of the SABAT neutron-based explosives detector integrated with an unmanned ground vehicle : a simulation study

The effective and safe detection of illicit materials, explosives in particular, is currently of growing importance taking into account the geopolitical situation and increasing risk of a terrorist attack. The commonly used methods of detection are based predominantly on metal detectors and georadars, which show only the shapes of the possible dangerous objects and do not allow for exact identification and risk assessment. A supplementary or even alternative method may be based on neutron activation analysis, which provides the possibility of a stoichiometric analysis of the suspected object and its non-invasive identification. One such sensor is developed by the SABAT collaboration, with its primary application being underwater threat detection. In this article, we present performance studies of this sensor, integrated with a mobile robot, in terms of the minimal detectable quantity of commonly used explosives in different environmental conditions. The paper describes the functionality of the used platform considering electronics, sensors, onboard computing power, and communication system to carry out manual operation and remote control. Robotics solutions based on modularized structures allow the extension of sensors and effectors that can significantly improve the safety of personnel as well as work efficiency, productivity, and flexibility

A new detector concept based on the prompt gamma radiation analysis for In vivo boron monitoring in BNCT

The problem of boron concentration monitoring during the boron neutron capture therapy (BNCT) therapy is one of the main challenges of this type of radiotherapy and is directly related to the nature of the interaction of neutrons with mater. Among the available in vivo methods of boron monitoring positron emission tomography seems to be very promising but it requires a new boron carrier with a β+ emitter, which is not yet clinically available. An alternative solution may be the prompt gamma radiation analysis (PGRA) based on the secondary radiation emitted in the interaction of neutrons with the patient’s tissues. This method requires, however, compact gamma radiation detection systems sustaining high counting rates and characterized by very good energy resolution. In this contribution, we present state-of-the-art solutions for monitoring in BNCT based on PGRA. Moreover, we describe a new concept of such a system based on position-sensitive scintillator detectors equipped with an anti-Compton shield and data analysis supported with modern artificial intelligence algorithms

3D PET image reconstruction based on Maximum Likelihood Estimation Method (MLEM) algorithm

Positron emission tomographs (PET) do not measure an image directly. Instead, they measure at the boundary of the field-of-view (FOV) of PET tomograph a sinogram that consists of measurements of the sums of all the counts along the lines connecting two detectors. As there is a multitude of detectors build-in typical PET tomograph structure, there are many possible detector pairs that pertain to the measurement. The problem is how to turn this measurement into an image (this is called imaging). Decisive improvement in PET image quality was reached with the introduction of iterative reconstruction techniques. This stage was reached already twenty years ago (with the advent of new powerful computing processors). However, three dimensional (3D) imaging remains still a challenge. The purpose of the image reconstruction algorithm is to process this imperfect count data for a large number (many millions) of lines-of-responce (LOR) and millions of detected photons to produce an image showing the distribution of the labeled molecules in space.Comment: 10 pages, 7 figure

Studies of discrete symmetries in decays of positronium atoms

A positronium - a bound state of electron and positron - is an eigenstate of parity and charge conjugation operators which decays into photons. It is a unique laboratory to study discrete symmetries whose precision is limited, in principle, by the effects due to the weak interactions expected at the level of 10−14 and photon-photon interactions expected at the level of 10−9. The Jagiellonian Positron Emission Tomograph (J-PET) is a detector for medical imaging as well as for physics studies involving detection of electronpositron annihilation into photons. The physics case covers the areas of discrete symmetries studies and genuine multipartite entanglement. The J-PET detector has high angular and time resolution and allows for determination of spin of the positronium and the momenta and polarization vectors of annihilation quanta. In this article, we present the potential of the J-PET system for studies of discrete symmetries in decays of positronium atoms