P. Raics

Excel2Genie, a simple and user-friendly Microsoft Excel interface, has been developed to the Genie-2000 Spectroscopic Software of Canberra Industries. This Excel application can directly control Canberra Multichannel Analyzer (MCA), process the acquired data and visualize them. Combination of Genie-2000 with Excel2Genie results in remarkably increased flexibility and a possibility to carry out repetitive data acquisitions even with changing parameters and more sophisticated analysis. The developed software package comprises three worksheets: display parameters and results of data acquisition, data analysis and mathematical operations carried out on the measured gamma spectra. At the same time it also allows control of these processes. Excel2Genie is freely available to assist gamma spectrum measurements and data evaluation by the interested Canberra users. With access to the Visual Basic Application (VBA) source code of this application users are enabled to modify the developed interface according to their intentions.

A part of the excitation function of the $^{232}\mathrm{Th}$(n,2n) reaction was determined by the foil activation method for neutron energies of 6.745, 6.938, 7.190, 7.448, 7.697, 7.944, 8.457, 8.975, 9.445, 9.934, and 10.450 MeV. Neutron flux density was measured using reactions $^{238}\mathrm{U}$(n,f), $^{56}\mathrm{Fe}$(n,p), and $^{27}\mathrm{Al}$(n,\ensuremath{\alpha}). Activity of the $^{231}\mathrm{Th}$ residual nuclei was determined by their low energy \ensuremath{\gamma} transitions detected with a high purity Ge spectrometer. Results of this experiment are compared with renormalized literature data.

The effect of irradiation on the optical absorption edge and thickness of AsSe and As2S3 thin films has been investigated for different doses of 12H, 11H accelerated to energies of 80 and 180 keV. The kinetics and value of the stimulated changes were compared with photo-induced effects of laser illumination at 0.51 and 0.63 μm. It was observed that the optical band gap decreases and the thickness increases for both cases. The penetration length and depth profile of implanted ions with different energies were calculated and proposed for creating layer structures with depth-profiled optical parameters.

This document describes results obtained from the Link alignment system data recorded during the Compact Muon Solenoid (CMS) Magnet Test. A brief description of the system is followed by a discussion of the detected relative displacements (from micrometres to centimetres) between detector elements and rotations of detector structures (from microradians to milliradians). Observed displacements are studied as functions of the magnetic field intensity. In addition, the reconstructed positions of active element sensors are compared to their positions as measured by photogrammetry and the reconstructed motions due to the magnetic field strength are described.

Magnet Cycles and Stability Periods of the CMS Experiment are studied with the Alignment Link System data recorded along the 2008–2013 years of operation. The motions of the mechanical structures due to the magnetic field forces are studied and the mechanical stability of the detector during the physics data taking periods is verified.

A study of the time required for the CMS detector to reach structural equilibrium once the magnetic field is ramped to its operational value of 3.8 T is presented. In addition, the results from a stability monitoring at 3.8 T over an eight-month period are given.

The aim of the investigations was to determine activity concentration of radioactive isotopes in soil samples collected from different provinces of Hungary. Earlier studies have proved that the (222)Rn activity concentration is higher than permitted in some wine cellars. To investigate the reason for this phenomenon, the activity concentration of soil samples was measured. Analyzing (137)Cs isotope activity in samples collected from the area of a watercourse it was possible to determine the silting-up rate. Activity concentrations were measured for red mud originating from an industrial disaster.

Measurements of aerosol activity from the Chernobyl reactor accident are reported. The concentrations of 14 radionuclides were obtained by gamma spectrometry for the period 30 April–9 May, 1986. Gross beta measurements were also done through 11 August 1986 of which137Cs activity concentrations were derived.90Sr activity concentrations were also determined for selected aerosol samples using nondestructive procedure. The time course of contamination observed in Debrecen (Hungary) is discussed in terms of trajectory analysis. Isotopic ratios are also used to trace down routes of contaminated air. In addition, such ratios are also used to characterize the status of the damaged reactor at different times.

Cross sections were determined for the reactions 90Zr(n,α)87mSr, 90Zr(n,p)90mY, 91Zr(n,p)91mY, 92Zr(n,p)92Y, 94Zr(n,α)91Sr, 94Zr(n,p)94Y and 96Zr(n,2n)95Zr using the foil activation technique. Neutrons have been produced via the 2H(d,n)3He reaction with a gas target on a variable energy cyclotron. The samples were irradiated with essentially monoenergetic neutrons at neutron energies of 5.4, 5.9, 6.4, 6.8, 8.2, 8.4, 8.9, 9.4, 10.2, 11.0, 11.6 and 12.3 MeV. Energy and energy spread of neutrons were calculated by the Monte-Carlo method and checked by scanning the neutron resonance absorption curve of 12C around 6.3 Mev. Neutron flux density was determined by reactions 27Al(n,α) and 56Fe(n,p).

Different empirical and semiempirical systematics have been developed to predict unmeasured fission product yields. One of these methods, originally proposed by Musgrove et al. and developed by Cook et al., is used to describe the energy dependence of the mass distribution in neutron-induced fission of 238U utilizing published yield data.The available measured cumulative yields of fission products are collected for monoenergetic 238U(n, f) processes. The mass distributions at approximate neutron energies of 1.5, 2.0, 3.0, 3.9, 5.2, 6.0, 7.0, 7.9, 9.0, and 14.7 MeV are fitted by the sum of five Gaussian functions. The energy dependence of the parameters of the Gaussian functions can also be described by semiempirical formulas. The 2σ error of the mass yields calculated by the fitted parameters can be estimated to be ∼10% in the peak regions and 20% in the valley region for the above neutron energies. The formulas with the given parameters can be useful in estimating unmeasured 238U fission product yields for any monoenergetic and nonmonoenergetic neutron irradiations in the range of 1.5 to 15 MeV. The method has been tested in a study of the 238U fission by neutrons having a Watt spectrum produced in the thermal fission of235U.

The central feature of the CMS Link alignment system is a network of Amorphous Silicon Position Detectors distributed throughout the muon spectrometer that are connected by multiple laser lines. The data collected during the years from 2008 to 2015 is presented confirming an outstanding performance of the photo sensors during more than seven years of operation. Details of the photo sensor readout of the laser signals are presented. The mechanical motions of the CMS detector are monitored using these photosensors and good agreement with distance sensors is obtained.

The World Year of Physics offers an opportunity to amuse secondary school pupils by experiments that they can perform themselves. The experiment described in this article enables them to visualize the invisible world of nuclear particles. The applied detector is particularly suited for classroom experiments.

During the past years our group has built, calibrated, and finally installed all the components of the Muon Barrel Alignment System for the CMS experiment. This paper covers the results of the hardware commissioning, the full system setup and the connection to the CMS Detector Control System (DCS). The step-by-step operation of the system is discussed: from collecting the analog video signals and preprocessing the observed LED images, through controlling the front-end PCs, to forming the measurement results for the CMS DCS. The first measurement results and the initial experiences of the communication with the DCS are also discussed.

Az OTKA altal tamogatott kutatas ket teruletre bonthato. I. A BNL RHIC gyorsitojanak PHENIX kiserleteben a meresekben es a kiserleti adatok analiziseben valo reszvetel: Csoportunk a PHENIX kollaboracio tagjakent dolgozott, munkaja beepult a PHENIX kiserlet kozos eredmenyeibe. Nehany teruleten a csoport hozzajarulasa kulonosen jelentős volt. Igy kiemelendő a jet-elnyomas jelensegenek vizsgalata kulonboző energiaju nehezion utkozesekben illetve az elektreomagneses kalorimeterrel kapcsolatos szimulacios es kalibracios tevekenyseg. II. Reszvetel a CERN-i LHC CMS kiserletenek epiteseben, ezen belul a barrel muon kamrak helyzetmeghatarozo rendszerenek fejlesztese es letrehozasa: a palyazati időszak alatt megepitesre kerult a teljes rendszer, amely lehetőve teszi a CMS barrel muon spektrometeret alkoto 250 nagymeretű driftkamra helyzetenek meghatarozasat szubmillimeteres pontossaggal. | The research activity supported by the OTKA fund can be divided in two groups. I. Participation in the measurements and the physics analysis of the PHENIX experiment at the RHIC accelerator in BNL (USA): our group worked in close collaboration with other members of the experiment so its work was integrated in the common results of the whole collaboration. In some areas, however, the contribution was particularly significant. Two areas can be emphasized, the investigation of jet suppression in heavy ion collisions at different energies and the simulation and calibration of the electromagnetic calorimeter. II. Participation in the construction of the CMS experiment to be installed at the LHC accelerator (CERN, Switzerland), development and construction of the barrel muon position monitoring system: the full system has been completed during the period of the OTKA-support. It allowes us to determine the positions of 250 large-scale drift-chambers forming the barrel muon spectrometer with submillimeter accuracy.

Between 1993 and 1996 a new 14.5 GHz electron cyclotron resonance (ECR) ion source was designed and built at ATOMKI for atomic and plasma physics research. In 1996 the assembling of the ion source has been finished and the first plasma diagnostic (visible and X-ray) measurements were carried out. In this work we started an investigation of the spectral distribution of the visible range of the electromagnetic spectrum. We studied the change of relative line intensities and the Xe2 to Xe1 ratio depending on the pressure inside the plasma. We were able to find spectral lines of Xe2 which are good candidates for plasma diagnostic tools in future investigations.

In the last year as part of the first test of the CMS experiment at CERN [1] called Magnet Test and Cosmic Challenge (MTCC) about 25% of the barrel muon position monitoring system was built and operated. The configuration enabled us to test all the elements of the system and its function in real conditions. The correct operation of the system has been demonstrated. About 500 full measurement cycles have been recorded. In the paper the setup –including the read-out and control is described and the first preliminary results are presented.

In order to be able to match correctly the track elements produced by a muon in the Tracker and the Muon System of the CMS experiment [1] the mutual alignment precision between the Tracker and the Barrel Muon System must be no worse than 100-400 micrometers depending on the radial distance of the muon chambers from the Tracker. To fulfill this requirement an alignment system had to be designed. This system contains subsystems for determining the positions of the barrel and endcap chambers while a third one connects these two to the Tracker. Since the Barrel muon chambers are embedded into the magnet yoke of the experiment a nonconventional alignment method had to be developed. In this paper we restrict ourselves to the Barrel Alignment System and the calibration methods of its components. I. THE BARREL MUON ALIGNMENT SYSTEM The CMS Barrel Muon Alignment System (Fig. 1) is based on an optical network of LED light sources and videocameras. The full system contains very large number of cameras (approx. 600 pcs) and LEDs (approx. 10000 pcs). Overwhelming part of these LEDs are mounted on the 250 barrel muon chambers while the cameras observing these LEDs are mounted on rigid structures called MABs (Module for Alignment of the Barrel). The MABs (36 pieces altogether) are fixed on the iron yoke of the magnet. Furthermore, there are about 300 LEDs and 100 cameras making direct connections between the MABs (called diagonal connections). Finally there are 6 long carbon-fiber bars located inside the barrel muon system containing in total 144 LED light sources allowing direct measurement of the Z coordinates of 24 MABs (where Z direction in the experiment corresponds to the direction of the proton beam path). The results of individual measurements are the positions of the centroids of the images of the LEDs measured by the cameras. In order to be able to reconstruct the positions of the muon chambers additional data -in addition to the measured centroidsis required. These are the parameters of the cameras (magnification, and tilt angles of the sensor with respect to the optical axis of the camera, sensitivity and homogeneity of the video-sensors of the cameras) and the positions of the LEDs on their holders. Also, the positions of the cameras and the LED holders in their embedding objects (muon chambers, MABs, Z-bars) are also needed. These additional data are obtained by the calibration of the elements. Figure 1. CMS Barrel Muon Alignment scheme II. CALIBRATION OF THE COMPONENTS The main requirement on the muon chamber alignment precision is in the range of 100-400 microns. Since this value depends also on the calibration precision of the components, the calibration methods had to be established such that the resulted precision of the full system could meet the above mentioned requirements. The individual calibration steps of the light source-related objects are the LED holder calibration and the barrel muon chamber alignment calibration, while calibration steps of the camera related objects are the camera quality control, the camera calibration and the MAB calibration. A. Light source related objects As it is mentioned above the basic components of the Barrel Muon Alignment System are the LEDs and the cameras. Individual LEDs are grouped into mechanical structures called LED holders containing 10 (for DT chambers), 3 (diagonal LED holders) or 6 (Z-LED holders) LEDs according to the measurement type. During the calibration process positions of the LED centroids in the frame of the LED holder are determined. The optical network requires most of the LED holders to be observed from both sides. This can be solved by introducing an auxiliary frame of reference which can be seen from both sides. Technically, this is a calibration tool containing multimode optical fibers illuminated by noncoherent light sources and shining into both directions. Positions of these light sources are measured in a high precision metrology lab and produce light distributions similar to those of the LEDs to be measured. Since the light spots are observed by cameras there was a requirement to exclude geometrical distortions and the error on centroid calculation caused by the un-even gain on the sensor surface. This has been solved by mounting the calibration tool (and therefore the LED holders) on a precise two-dimensional moving table and by constructing a successive method for moving all the centroids to a predefined position on the sensor surfaces. Therefore LED positions correspond to the position readouts of the moving table. Figure 2. Calibration bench for the LED holders. As the amount of LED holders is very large (>1200 pieces) a highly automated measurement method had to be developed. Both the successive centroid measurements and the control of the moving table and the LED holders are computerized. The operator only has to change the LED holders, identify it and start the measurement. The successive status then can be monitored on the computer console. Also due to the large number of LED holders an effective way of data handling and storage had to be developed. For such a large number of data (five complete measurements of all the LED holders ~ 100 k lines of raw data + 20 k lines of analyzed data) the use of a commercially available database solution is inevitable. Our team decided to use MySQL because it supports all the programming languages used in this calibration process under all operating systems. This database server also had an advantage because its installation requires only a moderate disk space and it is also freely available for research purposes. For data security reasons measurements are recorded as ASCII files which are automatically uploaded as the measurement finishes. Therefore one can assure to have two identical copies of the raw data and in case of critical failure of the database server data can be recuperated by using the same method used for synchronizing the database to the ASCII files. However, storage of data in a relational database provides a very easy way to compare the individual measurements therefore pinpointing any measurement errors based on statistical methods. This statistical analysis and the data recuperation are done by web-based Perl scripts allowing the access to the data from virtually everywhere without the need for special data handling software. Calibration methods of the diagonal and Z-LED holders are very similar to that of those ones described above. Figure 3. Data flow during the LED holder calibration [5] The main goal of the alignment system is to locate the anode wires of the muon chambers with respect to the Tracker. Muon chambers have a construction which doesn’t allow the observation of their anode wires after construction. This construction doesn’t allow either to determine the LED holder’s position with respect to the wires during chamber building. To overcome this problem the following technology has been developed: 1. During construction position of every anode wire (approx. 400 per chamber) is measured during the construction with respect to mechanical reference objects known as corner blocks mounted on each corner of a muon chamber’s Super Layer [2] (4 pieces per Super Layer). Since a muon chamber consists of two or three Super Layers depending on its type, a muon chamber can have eight or twelve corner blocks in total. These corner blocks serve as position references. 2. Since the position measurement of the LED holders is based on a centroid measurement while positions of the corner blocks can be determined by standard survey techniques (photogrammetry) an additional calibration bench had to be built. Here the corner blocks can be located by photogrammetry and the LED holders mounted on the chambers can be measured by cameras with pre-calibrated (known) positions with respect to the calibration bench. For this pre-calibration a specially designed calibration plate containing both optical fiber light sources and target holes for the photogrammetry is used. Internal parameters of these plates could be determined by a metrology laboratory. During the precalibration of the chamber bench these plates are localized by photogrammetry while a simultaneous measurement of the optical fibers has been performed by the cameras. A geometrical reconstruction is able to recuperate both the camera positions and their internal parameters needed for a correct measurement of the LED holders. 3. Applying mathematical transformations the positions of the LED holders can be determined in the chamber’s frame. As a byproduct the localization of all the Super Layers in the chamber’s frame can also be performed. The number of muon chambers to be measured was 264, therefore this calibration step also requires a reliable data handling strategy. Since during LED holder calibration the LED Holder Calibration

This document presents an overview of the induced photocurrents in the Amorphous Silicon Position Detectors used in the network of diode lasers and photo sensors of the CMS Link alignment system recorded during its eleven years of operation. After a description of the sensors characteristics, the layout of the sensors network is discussed. The sensors are distributed throughout the muon spectrometer and connected by laser lines. The data used correspond to readout information obtained during some of the physics runs from 2008 to 2018.

Experimental results for the232Th(n, 2n) reaction have been collected from the literature and evaluated. Updating of the measured cross section has been carried out with recent nuclear data. The recommended excitation function is described by the Pade approximation. Cross sections averaged over the spectra of neutrons from thermal neutron induced fission of235U and spontaneous fission of252Cf are also given.

The Muon Barrel Alignment system is based on the precise measurement of LED positions and signals of different sensors located in several predetermined places of the barrel. These data are collected by 36 PC/104 board computers. The board computers are organized in a network and controlled by a workstation, which communicates with the DCS system providing the precise status information of the barrel muon chambers. The aim of this paper is to describe the communication flow, the data hierarchy, the data structure, and the distribution of the tasks among the elements of the system. The first simulation and test results are also discussed.

Experiments on 50 μm thin PMMA sheets have been performed using a homogeneous 2 MeV proton beam of 5 mm diameter. The irradiations have been carried out at the Debrecen nuclear microprobe facility. For the characterization of the samples DIC microscopy and Twyman–Green interferometry have been used. It was found that the samples melted at a beam intensity dependent critical dose. Numerical calculations including heat transport and heat radiation corroborated the experimental results.

A szerző a Paksi Atomerőműben tortent sulyos uzemzavar es a termeszettudomanyos gondolkodas szinvonala kozotti osszefuggest vizsgalja

For the precise measurement of the positions of the barrel muon chambers in the CMS detector, a Position Monitoring System has been developed. It comprises ~10000 LED lightsources, 600 active pixel sensor monochrome video cameras, 24 tilt and 72 temperature sensors, 36 PC/104 board computers and a master control workstation for controlling the system and collecting and analyzing the data received from the sensors and cameras.

Neutron irradiation tests were performed with broad spectrum p(18MeV)+Be neutrons (En =3.5MeV) to study the neutron induced alterations of COTS (Commercially available Off The Shelf) optical and opto-electronic components (LED light source, LED driver, microcontroller, video camera, optical lens) of the CMS Muon Barrel Alignment system. Results of the tests are presented in this paper.

Neutron and proton irradiation tests were performed to study the radiation induced alterations of COTS (Commercially available Off The Shelf) CMOS active pixel sensors at two facilities. The sensors will be used for the CMS Barrel Muon Alignment system. Results of the tests are presented in this paper.

Statistical reaction model including preequilibrium emission as well as Hauser-Feshbach type contributions was applied to calculate the excitation function for the (n, xn) and (n, f) reactions up to 22 MeV bombarding energy using computer code STAPREF. The level density parameters were kept constant in excitation energy. Smalll variations of the fission threshold and the level density parameters from nuclide to nuclide within the experimental errors make it possible to achieve quite satisfactory agreement with the compilated cross sections above 3 MeV. The theoretical description of the isomeric ratio and the cross sections as a function of the neutron energy for the237Np(n, 2n) reaction may help to give recommendations for the excitation functions. Rotational parameters and decoupling constants were also calculated for ground state deformation and extrapolated to transition state.