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One of the basic parameters in the use of thermoluminescent detectors is the angular characteristics, i.e. receiving different signals depending on the angle of radiation exposure. The TLD detector is typically installed in a slide/badge and here the angular characteristics may have an influence, adding non-uniform coverage of the detectors with filters for the correct determination of the dose as a function of energy, because the energy characteristics are usually not flat. As part of the work, special MCP-N (LiF:Mg, Cu, P) detectors of various shapes were prepared to improve the angular characteristics. The detectors were round pellets with the same circular shape with a diameter of 4.5 mm, and a modified form inside (large and small drilled holes) or a modified surface (cavity or hemisphere). For comparison, standard MCP-N type detectors were used. Detectors in special boxes were exposed to X-rays with an energy of 80 keV. The radiation beam was formed by a medical X-ray apparatus adapted for experiments at the Warsaw University of Technology in Warsaw. Exposures were made for angles of 0, 30, 45, 50, and 90° for a dose of 1.5 mGy. Results show that it is possible to improve the angular characteristics for detectors with modified shapes. Better angular characteristics will allow for more accurate measurements, in particular in comparison tests, for accreditation and other calibrations. Especially improved angular dependence detectors could be useful for H*(10) environmental measurements. • Thermoluminescent detectors (TLD). • Angular dependence. • Environmental thermoluminescent detector. • Dose measurements. [ABSTRACT FROM AUTHOR]

In its statement on tissue reactions approved on 21st April 2011, the International Commission on Radiological Protection ( ICRP, 2012 ) reviewed its recommendation concerning the equivalent dose limit for the eye lens and reduced the dose limits for occupationally exposed persons to 20 mSv in a year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv. This limit was approved and written down in the new EURATOM (European Atomic Energy Community) directive 2013/59 and in the IAEA (International Atomic Energy Agency) BSS (Basic Safety Standard) of July 2014. For that reason, the necessity to monitor the eye lens may become more important than it was before. However, specially dedicated dosemeters for the dose quantity Hp(3) are using very rarely. Commonly use are only whole body personal dosemeters for the personal dose equivalent quantities Hp(10) worn on the trunk and ring dosemeters worn on finger to measure the quantity Hp(0.07). Therefore, in this work it was investigated whether dosemeters from routine use calibrated in terms of Hp(10) and Hp(0.07) and worn on thyroid collar and protective apron could deliver similar results like dedicated eye lens dosemeter worn close to the eyes. The results show that the best method if dedicated eye lens dosimeters is not used is to measure doses in terms of Hp(0.07) on the thyroid collar (Pearson product, r=0.85). Obtained results shows also importance of proper localization of eye lens dosimeter (close to the eye, from side of the X-ray source). [ABSTRACT FROM AUTHOR]

Erasure of the thermoluminescence (TL) signal on detector readout is considered to be a disadvantage of TL dosimetry, as post-readout dose reassessment is then impossible in principle. A method of dose reassessment based on phototransferred thermoluminescence (PTTL) has been developed at the Institute of Nuclear Physics, Polish Academy of Sciences (IFJ PAN) and applied to MTS-N (LiF:Mg,Ti) detectors. We demonstrate the possibility of applying PTTL for dose reassessment in MTS-N TL detectors routinely applied in the dosimetric service at IFJ PAN. Readings of TL detectors exposed to relatively high doses by the customers of our dosimetry service can now be reassessed using our automatic readers. A major obstacle in applying the PTTL method at lower exposures is the presence of residual dose accumulated in LiF:Mg,Ti detectors after many field exposure and readout cycles. Since most of the TL detectors in our service have been already used for a long time (e.g. for over 10 years in the case of some detector batches), we find that our PTTL method of dose reassessment is possible only in detectors which had received doses exceeding 5 mSv. [ABSTRACT FROM AUTHOR]

We report results of measurements of Hp(10) from whole body dosimeters (about 53 thousand readouts), of Hp(0.07) from finger ring dosimeters (23 thousand readouts) and of Hp(3) from eye lens dosimeters (100 readouts), issued in the years 2010-12 to over 150 medical departments in Poland which apply X-rays in radiology, interventional radiology (haemodynamic, angiology, cardiac surgery), urology, orthopaedics, electrophysiology or electro-cardiology. In all measurements thermoluminescence detectors (TLD) were used: the well-known standard MTS-N (LiF:Mg, Ti) for whole body and extremity dosimetry, and the high-sensitivity MCP-N (LiF:Mg, Cu, P) for eye lens dosimetry and environmental monitoring. We analysed the data base of the accredited Laboratory of Individual and Environmental Dosimetry (LADIS) at the Institute of Nuclear Physics PAN which offers its dosimetry service to these departments on a regular basis. We found that in the population of radiation workers that studied over the years 2010-2012 in 84%, 87%, and 34% of Hp(10), Hp(0.07) and Hp(3) measurements, respectively, the level of 0.1 mSv/quarter did not exceed, indicating lack of their occupational exposure. In the remaining 16%, 13% and 66% of individual cases, the 0.1 mSv/quarter exceeded, occasionally reaching several hundreds of mSv/quarter. [ABSTRACT FROM AUTHOR]

Abstract: The thermoluminescent (TLD) method is one of the most commonly used in dose measurements in radiation protection dosimetry. Due to its many advantages this method is widely spread. However, TLD has especially one disadvantage which is very inconvenient: the dose information in already read detectors is erased and in routine standard way the dose can not be reassessed. The positive is that this shortcoming can be eliminated by applying UV radiation. After first readout the same detector can be subjected to UV exposure and then read once again to reassess the dose. This method for reassessment of dose is based on phototransferred thermoluminescence (PTTL). In an irradiated TL detector deep traps are not emptied during the first readout. During exposure to UV, electrons are transferred from deep traps to shallower dosimetric traps. This TL signal emerging during the second readout following UV illumination is called phototransferred thermoluminescence. A method for reassessment of dose in a previously readout TLD is presented in this work. Experiments show that the method works well within region of doses between 5 and 50 mGy, but could be applied for higher doses as well. The efficiency of dose reassessment reaches about 17 percent of the first readout. The method could be a noticeable improvement in TLD dosimetry, giving more opportunities for better control and reliability of measurements. [Copyright &y& Elsevier]

Abstract: Following the recent ICRP recommendation to decrease the limit of occupational exposure to the eye lens from 150 mSv to 20 mSv/year, a dedicated individual eye-lens dosemeter, EYE-D™, was developed at the IFJ PAN. This dosemeter uses MCP-N (LiF:Mg,Cu,P) thermoluminescent detectors covered with a polyamide capsule and was so far optimized to achieve a flat photon energy and angular response for X-ray exposures typical in interventional radiology. To verify the applicability of this eye-lens dosemeter in external β-ray fields which arise, e.g. in nuclear medicine procedures, we measured and calculated its β-ray energy and angular response. Measurements, applying β-rays from Sr-90/Y-90 isotope, were performed at the Beta Secondary Standard type 2 (BSS 2) in CLOR. Calculations, using the PENELOPE Monte Carlo transport code which simulates coupled electron and photon transport in arbitrary materials, were performed for P-32, K-42 and Sr-90/Y-90 fields to simulate doses received by the eye lens within the human body. PENELOPE Monte Carlo transport code was also used to calculate doses received with EYE-D™ detectors. We found good agreement between the measured and calculated energy and angular responses which confirms the suitability of this dosemeter in assessing Hp(3) to estimate the eye lens. Obtained results and conclusions, however preliminary, conform with current ICRP recommendations when performing individual radiation protection dosimetry in external β-ray fields occurring in nuclear industry and nuclear medicine activities. [Copyright &y& Elsevier]

Abstract: Using a two-dimensional thermo luminescent (TL) system consisting of MCP-N (LiF:Mg,Cu,P) TL detectors and self-developed TLD reader with a CCD camera (TL-CCD reader) a method of distinguishing between static and dynamic radiation exposure to X-rays was developed. MCP-N TL detectors installed in the RADOS dosimetry badge were covered with non-uniform Pb and Cu filters. Quantitative identification of the static exposure cases was performed by analyzing the distribution of pixel intensity in the images obtained in the TL-CCD reader (). We demonstrate the possibility of automatically distinguishing cases of static exposure for doses as low as 5 mSv, up to mean X-ray energies of 250 keV and for exposure angles up to 60°. [Copyright &y& Elsevier]

Abstract: We performed individual dose measurements, in terms of Hp(10) for the whole body, Hp(0,07) for the extremities (hands) and Hp(3) for the eyes, for medical personnel (technical staff, nurses and medical doctors) in three nuclear medicine departments. One conventional diagnostic scintigraphy department, where Tc-99m, I-131 and Sm-153 were applied, and two PET-CT departments where F-18 was applied in preparation and application procedures, were studied. A novel eye lens dosemeter was used, designed to evaluate Hp(3) directly. From our measurements we obtained ratios of Hp(3)/Hp(10) ranging between 0.7 and 1.1 indicating that in nuclear medicine procedures eye lens doses could probably be estimated from Hp(10) values and that exceeding the present annual dose limit to eye lens (150 mSv) is very unlikely. The relationship between different individual doses can indicate the quality of radiation protection in a nuclear medicine department. [Copyright &y& Elsevier]

Abstract: We have measured inclusive data on -meson production in pp collisions at COSY Jülich close to the hyperon production threshold and determined the hyperon–nucleon invariant mass spectra. The spectra were decomposed into three parts: Λp, and . The cross section for the channel was found to be much smaller than a previous measurement in that excess energy region. The data together with previous results at higher energies are compatible with a phase space dependence. [ABSTRACT FROM AUTHOR]

Due to their low radioactivity background, underground physics laboratories offer a unique possibility for investigating extremely rare phenomena like proton decay, dark matter signals or neutrino physics/astrophysics related issues. The knowledge of the natural radioactivity background is essential for the success of an underground physics experiment. The following measurements of the natural radioactivity background, in the foreseen location of an underground physics laboratory in the salt layer, in the Polkowice-Sieroszowice copper mine are presented: concentration of natural radio-isotopes from in situ obtained gamma-ray spectra and from alpha spectroscopy of rock samples, radon concentration in the air and the dose determination. [ABSTRACT FROM AUTHOR]

Abstract: The reaction was measured at and with a high missing mass resolution in order to study the Λp final state interaction. The large final state enhancement near the Λp threshold can be described using the standard Jost-function approach. The singlet and triplet scattering lengths and effective ranges are deduced by fitting simultaneously the Λp invariant mass spectrum and the total cross section data of the free Λp scattering. [Copyright &y& Elsevier]

Abstract: In view of the implementation of beam-monitoring sensors for CERN''s Large Hadron Collider (LHC), and also in order to validate Thermoluminescence Detectors as a versatile tool to measure ionizing radiation doses in mixed fields at hadron colliders such as the LHC, chemical vapor deposition diamond sensors have been evaluated and calibrated at CERN''s Proton Synchrotron accelerator. Special attention was paid to understanding whether lithiumfluoride thermoluminescence detectors are suitable as measuring devices in these radiation fields. [Copyright &y& Elsevier]

We have performed an experiment to search for the bound state of η meson in nuclei. We have measured the reaction p + 27Al → 3He + p + π- + X at recoil-free kinematics. An η meson possibly produced in this reaction would be thus almost at rest in the laboratory system and could therefore be bound with high probability, if bound nuclear η states exist. The decay of such a state through the N*(1535) resonance would lead to a proton-π- pair emitted in opposite directions. For these conditions we find some indication of such a bound state. An upper limit of ≈ 0.5 nb for the formation cross section is found. [ABSTRACT FROM AUTHOR]

Abstract: The angular distributions of the unpolarised differential cross section and tensor analysing power of the reaction have been measured at an excess energy of 16.6 MeV. The ambiguities in the partial-wave description of these data are made explicit by using the invariant amplitude decomposition. This allows the magnitude of the s-wave amplitude to be extracted and compared with results published at lower energies. In this way, firmer bounds could be obtained on the scattering length of the ηα system. The results do not, however, unambiguously prove the existence of a quasi-bound ηα state. [Copyright &y& Elsevier]

The extracted s-wave scattering amplitude from both the polarized and unpolarized d + d → 4He + η reaction at 2385.5 MeV/c allowed to determine the scattering length which fulfills the requirements for bound η. In the p + 27Al → 3He + p + π- + X reaction studied at recoil free kinematics the η meson is produced almost at rest and so it can be bound with enhanced probability. This state proceeds via N*(1535) resonance and the decay products proton and pion emitted into opposite direction are detected in concidence with 3He produced at zero degree. Under these conditions some hints for bound state can be observed with an upper limit of the cross section of ≈ 0.5 nb. [ABSTRACT FROM AUTHOR]

The charge and relative velocity distributions of forward emitted fragments in the 22Ne + 9Be reaction at bombarding energy of 40AMeV are presented. Experimental results are compared with the quantum molecular dynamics (QMD) model taking into account in calculations the mean field-like effects and the two-body scattering term. In the theoretical analysis a subsequent statistical decay of excited primary reaction products following the QMD predictions is applied. The assumption of two scenarios responsible for production of forward emitted fragments results in a good representation of the data suggesting a preferential contribution of the mean field-like effects in production mechanism. [ABSTRACT FROM AUTHOR]

Abstract: A new threshold Cherenkov detector has been built for the detection of charged pions in the focal plane of a magnetic spectrograph. Silica aerogel with refractive index of is applied as a radiator. The detector exhibits a very high detection efficiency for pions with momenta . Using two Cherenkov detectors in series a very high pion suppression factor of was achieved. [Copyright &y& Elsevier]

Abstract: To distinguish between static and dynamic (normal) exposure of personal TL dosimeters, a model of radiation deposition and of TL light transport in the TLD dosimeter is proposed. The RADOS dosimeter badge using MCP-N (LiF:Mg,Cu,P) TL detectors with standard filters replaced by special Pb and Cu filters with a pattern of holes or inserts was modelled. The photon radiation transport in the dosimeter and energy deposition in the TL detector were simulated by the Penelope Monte Carlo transport code. The model of TL light transport within the TL pellet takes into account the distribution of energy deposition in the TL detector, light self-absorption in the detector and reflection of TL light of the heating planchet. The shape and hole pattern of the filters were optimized with respect to best distinction between static and dynamic exposures. The results of calculations were verified experimentally by exposing RADOS badges with modified filters to beams of low energy X-rays directed at various angles. [Copyright &y& Elsevier]

An experiment to search for the bound state of η meson in nuclei has been performed at COSY, Juelich using the ENSTAR detector and Big Karl magnetic spectrometer. Reaction (p,3He) on 27Al target has been used to search for the η-mesic nucleus 25Mgη in the missing mass distribution from the measured 3He particles. A preliminary figure of 1.5 nb for the upper limit of the formation cross section of η-nucleus bound state has been determined. [ABSTRACT FROM AUTHOR]

Abstract: Several processes of meson production in proton–deuteron collisions have been measured simultaneously using a calibrated magnetic spectrograph. Among these processes, the η meson is seen clearly as a sharp missing-mass peak on a slowly varying background in the reaction. Knowing the kinematics of the other reactions with well determined masses, it is possible to deduce a precise mass for the η meson. The final result, , is significantly lower than that found by the recent NA48 measurement, though it is consistent with values obtained in earlier counter experiments. [Copyright &y& Elsevier]

Abstract: The positively charged pions produced in proton–proton collisions at a beam momentum of 1640 MeV/c were measured in the forward direction with a high resolution magnetic spectrograph. The missing mass distribution shows the bound state (deuteron) clearly separated from the pn continuum. Despite the very good resolution, there is no evidence for any significant production of the pn system in the spin-singlet state. However, the cross section ratio is about twice as large as that predicted from S-wave final-state-interaction theory and it is suggested that this is due to D-state effects in the pn system. [Copyright &y& Elsevier]

An environmental radiation monitoring system using standard MTS-N (LiF:Mg, Ti) and high-sensitive thermoluminescent LiF:Mg,Cu,P (MCP-N) detectors was applied to control the radiation exposure over the area of the Institute of Nuclear Physics (INP) in Kraków. First environmental measurements using MTS-N detectors began in 1970 at five locations and were continued during the Chernobyl accident at six sites. In March 1987 high-sensitive MCP-N detectors read out in a manual TL reader were first introduced into service at the INP. Since 1992 about 60 locations over an area of the INP were selected for quarterly dose rate measurements, using an automatic TLD system based on MTS-N detectors placed in cards. In 2002 MTS-N detectors were replaced by high-sensitive MCP-N pellets.The dose rate in long-term measurements changed over the last 30 years. The average gamma dose rate over the area of INP in the years 1975–1978 was 63 nGy-1. After the Chernobyl accident the gamma dose rate increased to 880 nGyh-1. In December 1986 the dose rate at the location place decreased to 103 nGyh-1. At present, the average dose rate has returned to the pre-Chernobyl level of about 68 nGyh-1. Construction and beam tests of a new isochronous cyclotron at the INP resulted in highly enhanced environmental dose rates at several monitored INP sites. In this work results of almost 11 years of environmental indoor and outdoor measurements with thermoluminescent detectors are summarised. [Copyright &y& Elsevier]

The properties of LiF:Mg,Ti (distributed as, e.g., TLD-100 or MTS-N), the most frequently used thermoluminescent detector, have been optimised for measurements of sparsely ionising radiation (gamma rays), typically encountered in radiation protection or clinical dosimetry. However, these detectors need also to be applied in conditions of mixed-field dosimetry with a high-LET component, such as those encountered in heavy ion beams or in space.At the Institute of Nuclear Physics in Kraków a new type of LiF:Mg,Ti detector (named MTT) has been recently developed through modification of its dopant composition. This composition is intended to increase the detection efficiency after a dose of high-LET radiation. The concentration of dopants in the MTT material is: CMg=50 ppm, and CTi=120 ppm, i.e. about a three times less of magnesium and about 10 times more of titanium content, compared with the standard MTS-N. The MTT TL detectors feature an increased relative efficiency to high-LET radiation, which for 5 MeV alpha-particles is about twice that of standard LiF:Mg,Ti. The response of MTT detectors has been studied in charged particle beams of the HIMAC accelerator in Chiba, Japan and in Dubna, Russia. The main foreseen application of MTT detectors are dose measurements in space. The dose after high-LET exposure can be estimated from the difference of the response of MTS and MTT detectors. In the near future MTT detectors will be applied in the “Matroshka” experiment. Within this experiment a specially constructed human phantom will be exposed in free space (outside the International Space Station) for 1 year. The phantom will incorporate a few thousand measuring points enabling radiation doses to particular organs to be determined. [Copyright &y& Elsevier]

It has been argued recently that the so-called nuclear modification factor (RAA) is an observable useful for identifying the quark–gluon plasma. We discuss the effect of Fermi motion in nuclei on RAA at CERN SPS and BNL RHIC energies. Contrary to the simple intuition, rather large effects are found for CERN SPS. The Fermi motion in nuclei contributes significantly to the Cronin effect. The effect found is qualitatively similar to the one observed experimentally at CERN energies and similar to the one obtained in the models of multiple scattering of initial partons. We predict different size of the effect for different types of hadrons, especially at low energies. [ABSTRACT FROM AUTHOR]

The paper describes modifications of the Ju¨lich magnetic spectrometer Big Karl needed to study meson production and especially to investigate charge symmetry breaking effects—an experiment that requires a high-precision measurement. New elements that have been added to Big Karl have extended the spectrometer capabilities to a much wider momentum range. The new features also facilitate simultaneous detection of particles with very different rigidities. The experimental methods for improving background and determining relative acceptance of the spectrometer at various rigidities are presented. [Copyright &y& Elsevier]

The Forward Wall Detector (FWD) is designed to identify projectile-like fragments from heavy-ion reactions at the CELSIUS storage ring in Uppsala, Sweden. FWD covers the polar angle from 3.9° to 11.7° with geometrical efficiency of 81%. The single-detection module can be either of phoswich type (10 mm fast plastic+80 mm CsI(Tl)) or ΔE−E telescope (750 μm Si+80 mm CsI(Tl)). It is expected to have charge identification up to Z=18 and mass resolution for H and He isotopes. [Copyright &y& Elsevier]

Abstract: A quantitative method was developed to distinguish cases of static and dynamic exposure of personal dosimetric badge with thermoluminescence (TL) detectors. Standard RADOS badge with LiF:Mg,Cu,P (MCP-N) detectors with a modified, non-uniform Pb filter, were exposed in X-rays and γ-rays and evaluated using TL reader with CCD camera. From the frequency distribution of pixel intensity the coefficient of static exposure ws was calculated which was next used to quantify the static exposure. This method was successfully applied to identify the cases of static exposure for X-rays energies up to approximately 150 keV, at different angles of irradiation and doses exceeding 5 mSv. The procedure will be applied in the routine dosimetric service at IFJ PAN. [Copyright &y& Elsevier]

It has been seven years from the ICRP Statement on tissue reactions containing the recommendations for an equivalent dose limit for the lens of the eye of 20 mSv per year for workers (ICRP, 2012), and has been 7 years since Laboratory of Individual and Environmental Dosimetry (LADIS) introduced in practice eye lens doses measurement. The reduction of the limit for occupational exposure for the lens of the eye needs adequate approaches for eye protection and eye dose monitoring. The most accurate method for monitoring the equivalent dose to the lens of the eye is to measure the personal dose equivalent Hp(3) with a dedicated dosimeter worn as close as practicable to the eye. To measure eye lens doses in terms of this quantity a dosemeter and an appropriate method has been introduced in the largest dosimetry service in Poland. This paper presents historically the introduction of eye lens dosimetry in routine measurements and an analysis of the exposure results of the eye lens dose sl. Results of measurements of Hp(3) from eye lens dosemeters (almost 5000 quarterly readouts), issued in the years 2012–2018 were reported. In measurements EYE-DTM dosemeter developed within ORAMED EU project (Vanhavere et al., 2011) and high-sensitivity MCP-N (LiF:Mg, Cu, P) thermoluminescence detectors were used. The frequency distribution of eye lens dose measurements performed using specially dedicated dosemeters, via their Hp(3) operational values, over 3-month periods, after subtraction of natural background in 74% cases are below 0.1 mSv. In the case of the new operational quantity, Hp(3) the number of workers, which exceed the new limit during 7 years monitoring period was 48 (1%). The study showed considerable uncertainties associated with the assessment of eye lens dose from the commonly used whole body dosemeters on the chest in terms of Hp(10) and ring dosemeters on the finger which measures skin doses in terms of Hp(0.07). Therefore, only monitoring of the eyes with specific dosemeters for yearly follow-up can provide accurate annual doses. • Improvement of eye lens dosimetry to interventional radiology and cardiology staff and to nucelar medicine. • The obtained dosimetry data could be used for epidemiological studies to assess retrospectively eye lens dose. • 5000 Readouts of eye lens doses are presented. [ABSTRACT FROM AUTHOR]

Patient kerma–area product P KA , cumulative kerma in the air K IRP , fluoroscopic time t, personal dose equivalent (in terms of Hp(10), Hp(0.07) and Hp(3)) for most common interventional cardiology procedures were measured. P KA and K IRP measurements were used for patients and thermoluminescent dosimetry for the personnel. Dosemeters for personal doses measurements containing MCP-N (LiF: Mg, Cu, P) type thermoluminescence detectors (TLDs), were read out at the Institute of Nuclear Physics Polish Academy of Science (IFJ PAN) dosimetry service. The patient and personal doses were similar to those reported by other authors. The mean values of total kerma–area product (P KA ) were 22.7 (7.3–50.9) Gy·cm 2 for coronary angiography (CA) and 43.1 (3.2–86.4) Gy·cm 2 for percutaneous coronary intervention (PCI). In general, doses received by the staff performing PCI procedures were found to be systematically higher than those after CA procedures, by some 30% or more. Within the medical team, operators always received the highest doses, followed by nurses and technicians. Maximum eye lens doses, skin doses and whole body doses were 165 μSv, 962 μSv and 30 μSv per procedure, respectively. Annual eye lens doses received by the operators, especially in PCI procedures, may well exceed the value of the recently recommended annual dose limit of 20 mSv and should be monitored. No meaningful correlation could be established between occupational doses and patient exposure, however some degree of correlation was observed between values of dose to the eye lens and whole body dose. [ABSTRACT FROM AUTHOR]

The goal of the present work was to conduct an initial screening survey of several types of TL and OSL detectors, aimed at searching for the indication of the presence of dose rate effects. The study has been performed on ten different materials: LiF:Mg,Ti; LiF:Mg,Cu,P; CaF 2 :Dy; Al–P glass; YAP:Mn; CaSO 4 :Dy; Al 2 O 3 :C; BeO; MgB 4 O 7 :Ce.Li and quartz. Gamma-ray dose rates ranged from 0.1 mGy/h to 90 Gy/h. No clear evidence of dose rate effects was found for any material. In two cases (MgB 4 O 7 :Ce,Li and BeO) some irregularities of the response were observed, which require further investigations but most probably they are not attributable to the dose rate influence. • The analysis of TL/OSL detectors in a wide range of radiation doses was conducted • No clear evidence of dose rate (ranged 0.1 mGy/h - 90 Gy/h) effects was found • In case of MgB 4 O 7 :Ce,Li some irregularities of the response was observed [ABSTRACT FROM AUTHOR]

Abstract: A new detection system KRATTA, Kraków Triple Telescope Array, is presented. This versatile, low threshold, broad energy range system has been built to measure the energy, emission angle, and isotopic composition of light charged reaction products. It consists of 38 independent modules which can be arranged in an arbitrary configuration. A single module, covering actively about 4.5msr of the solid angle at the optimal distance of 40cm from the target, consists of three identical, thick, large area photodiodes, used also for direct detection, and of two CsI(1500ppm Tl) crystals of 2.5 and 12.5cm length, respectively. All the signals are digitally processed. The lower identification threshold, due to the thickness of the first photodiode, has been reduced to about 2.5MeV for protons ( of Si equivalent) by applying a pulse shape analysis. The pulse shape analysis allowed also to decompose the complex signals from the middle photodiode into their ionization and scintillation components and to obtain a satisfactory isotopic resolution with a single readout channel. The upper energy limit for protons is about 260MeV. The whole setup is easily portable. It performed very well during the ASY-EOS experiment, conducted in May 2011 at GSI. The structure and performance of the array are described using the results of Au+Au collisions at 400MeV/nucleon obtained in this experiment. [Copyright &y& Elsevier]

The longitudinal velocity and isotopic distributions of forward emitted fragments have been measured in the 11B (32.9 AMeV) + 9Be (27Al,197Au) reactions. The range of isotopes from Helium to Nitrogen has been observed. The particular interest of this experiment has been to investigate the influence of direct and dissipative processes on the fragment production for different targets. The fast velocity component characterized by a Gaussian shape is rather well described in the frame of simple statistical fragmentation model, but with smaller value of the width of the distribution. Isotopic and velocity distributions have been compared to Universal Parameterization model implemented in the LISE + + code. Increased yields of 4He and 7Li isotopes are observed as a possible influence of the cluster structure of the 11B nuclei on the total reaction mechanisms. [ABSTRACT FROM AUTHOR]

Thermoluminescent (TL) detectors are an established method for passive dose measurement. Over the last several years MCP-N (LiF:Mg,Cu,P) detectors have been widely used in modern TL dosimetry due to their very high sensitivity (at the microgray level) and their simple signal-dose relation. Their dose response does not show any supralinearity up to saturation at about 1 kGy. Only recently we have discovered their quite unexpected proper- ties at high and ultra-high doses, which enable us to use them for measurements of doses from micrograys up to a megagray. Significant changes of the glow-curve shape occur for doses higher than a few kGy and what is most important, a new peak appears in their glow-curve at exposures above 50 kGy, the position of which shifts towards higher temperatures with increasing dose. The presented method is based on these properties. This method is also a promising way of measurements of doses in mixed radiation fields. [ABSTRACT FROM AUTHOR]

A comparison of the close–to–threshold total cross section for the η' production in pp → ppη' and pn → pnη' reactions constitutes a tool to investigate the η' meson structure and the reaction mechanism in the channels of isospin I = 0 and I = 1 and may provide insight into the flavour-singlet (perhaps also into gluonium) content of the η' meson. In this contribution we present preliminary results of measurement of the quasi-free production of the η' meson in the proton-neutron collisions conducted using the COSY-11 facility. [ABSTRACT FROM AUTHOR]

We have measured excitation function for dp → pppπ- reaction near the η production threshold. We observe an enhancement of the counting rate above the threshold which can originate from the production of the η meson in the reaction dp → 3He η and its subsequent absorption on neutron in the 3He nucleus leading to creation of the pπ- pair. [ABSTRACT FROM AUTHOR]