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In this investigation we prepared samples of Cantor alloy, i.e. Fe20Co20Cr20Mn20Ni20 and re-melted them in a nitrogen-argon atmosphere by electric arc to dissolve nitrogen into the ingot, followed by aging for 24 h at 800 °C to precipitate nitride in the ingot. The microstructure, hardness and compressive strength of the three fabricated alloys were characterized and compared. Inductively coupled plasma (ICP) measurement found that high nitrogen content of 3.51 at% was successfully dissolved in the ingot, which is significantly higher than the nitrogen contents in most of the nitrogen-doped high entropy alloys reported so far. The ingot preserved the typical single-phase, face-centered cubic structure of Cantor alloy. After aging the ingot at 800 °C for 24 h, lamellar Cr2N precipitates were found and its volume fraction was estimated to be 3.6%. The Vickers’ hardness of nitrogen-dissolved and aged alloy was increased from 133 HV to 235 HV and 262 HV respectively, while their yield strength increased from 192 MPa to 336 MPa and 416 MPa, respectively.

Luminescence dosimetric properties of inductors and resistors in mobile phones have attracted wide attention for their use in retrospective accident dosimetry. Thermoluminescence (TL) signal following optically stimulated luminescence (OSL) readout, which has been recently shown to be useful for dose re-estimation (Lee et al., 2016), when measured by a Risoe OSL reader without a Hoya U-340 optical filter, was found to be up to 85 times of that recorded with the Hoya filter (with transmission window 270–380 nm, necessary for recording the usual OSL signal) placed in front of the photomultiplier tube (PMT) in the reader. In view of this, a study of dosimetric TL properties, namely sample-to-sample variation, fading, zero-dose signal, minimum measurable dose, effect of room light, dose response and emission spectrum, was undertaken to explore the use of TL of inductors and resistors in new generation mobile phones for accident dosimetry. The hitherto unknown TL emission spectrum was found to exhibit an intense emission beyond 550 nm (peaking at 700 nm) when recorded in the range from 250 nm to 750 nm. Emission below 500 nm was smaller by orders of magnitude than that at 700 nm. As the TL and OSL signals have been attributed to alumina substrates of inductors and resistors, the TL emission spectrum was compared with that of dosimetry grade Al 2 O 3 :C. The emission spectra of inductors and resistors were found to differ significantly, not only from that of Al 2 O 3 :C, but also from each other. Although the differences in TL glow curves, optical emission spectra, fading, etc. Indicated a lack of universality in luminescence properties of alumina substrates in different electronic components, it was concluded that the TL of inductors and resistors in new generation mobile phones offers a better option for accident dosimetry than OSL, with the specific advantage of much lower post-irradiation fading.

In the recent years, intensive research on the application of optically stimulated luminescence (OSL) from alumina rich electronic components, such as resistors and inductors of electronic gadgets, is being carried out for retrospective dosimetry in the event of radiological accidents or terroristic attacks. It was noted that in inductors of mobile phones, the OSL readout did not significantly affect the thermoluminescence (TL) signal of glow peaks above 200 °C which exhibited negligible fading. This effect was exploited to re-estimate the doses by using TL signal (“residual TL”) of the inductors and the resistors which were already subjected to OSL readout for the estimation of the given doses. The dose response of the residual TL signal was also found to be linear up to about 4 Gy for both the inductors and resistors. The estimation of doses by using OSL and the re-estimation by using residual TL was carried out for the nominal doses of 300 mGy, 1700 mGy and 3300 mGy. The estimated doses and the re-estimated doses were in the range of about 80%–97% of the nominal doses for the inductors and in the range of about 76%–111% for the resistors. It was concluded that the residual TL could be used for the re-estimation of doses in some cases of radiological accidents.

The thermoluminescence of different chip cards was measured and analyzed for emergency dosimetry. Three SIM cards that are commonly found in mobile communication providers in South Korea and three smart IC cards that can be purchased online were used for the experiment. Chemical element analysis based on EDS mapping images was carried out and different weight percent of silica was found for each chip card. Glow curves of radiation induced signals through different combinations of optical filters showed blue or red emissions depending on chip cards. Sensitivity change resulting from the thermal stimulation was found to be 1.8 ± 0.27 and 0.5 ± 0.06 for the blue and red emission, respectively. In addition, signal fading resulted in more than 20% of the initial signal remaining 20 days after irradiation, when the 100–150 °C signal is used. Furthermore, the dose response was recorded from 50 mGy to 10 Gy for each chip card.

Phototransferred thermoluminescence (PTTL) of mobile phone display glass (category A) is systematically investigated to develop a robust measurement protocol for its emergency dosimeter usage after an incident with ionizing radiation. First, optimal readout parameters were defined by varying preheat temperature and holding time preceding violet exposure (405 nm). Next, the detection window of the PTTL measurement was adjusted to optimize the ratio between radiation-induced (RIS) and non-radiation-induced signals (nRIS) of the PTTL. Finally, the developed protocol determines PTTL after preheating to 400 °C and holding for 10 s was tested using the detection window centered at 340 nm. Dosimetric properties such as the PTTL reproducibility and dose response were investigated. PTTL signal stability tests showed that the violet PTTL signal originates from deeper and consequently more thermally stable traps. A signal loss of less than 10% after 10.6 days (254 h) storage was observed. Additionally, TL and PTTL spectra were recorded to investigate the luminescence emissions after beta and gamma irradiation and different UV exposures. PTTL emissions are similar to TL emission. Varying UV energy a qualitative comparison demonstrate that the RIS and nRIS PTTL signal intensities increase significantly with decreasing UV stimulation wavelength. In general, the developed PTTL protocol indicates better signal stability and thus some advantages over other techniques, however, further research is needed to test the potential of a new method for physical retrospective dosimetry.

Optically stimulated luminescence (OSL) characteristics of resistors, inductors and integrated-circuit (IC) chips, extracted from new generation smart phones, were investigated for the purpose of retrospective accident dosimetry. Inductor samples were found to exhibit OSL sensitivity about 5 times and 40 times higher than that of the resistors and the IC chips, respectively. On post-irradiation storage, the resistors exhibited a much higher OSL fading (about 80 % in 36 h as compared to the value 3 min after irradiation) than IC chips (about 20 % after 36 h) and inductors (about 50 % in 36 h). Higher OSL sensitivity, linear dose response (from 8.7 mGy up to 8.9 Gy) and acceptable fading make inductors more attractive for accident dosimetry than widely studied resistors.

Radioluminecscence (RL), the light emitted from a material immediately upon ionizing radiation, has been used to detect the dose rate. On the other hand, thermoluminescence (TL) and optically stimulated luminescence (OSL) by the stimulation with the heat and light after irradiation have been used to find out the cumulated radiation dose. Because it was considered as effective to handle these three phenomena in integration to estimate the energy band structure of the material precisely, an algorithm for calculating the glow rapidly and consistently was developed in this study when three types of stimulations including irradiation are applied concurrently or sequentially. The deconvolution using this algorithm can decide the properties contained in the material more precisely because the glows from different stimulations are related frequently to the different aspects of the properties. The computer program to realize the deconvolution by means of these schemes was also developed and it was applied to the glow curves of RL and OSL from Al 2 O 3 :C to evaluate the efficiency of the developed algorithm.

An algorithm was developed to integrally handle excitation by radiation, relaxation and luminescence by thermal or optical stimulation in thermoluminescence (TL) and optically stimulated luminescence (OSL) processes. This algorithm reflects the mutual interaction between traps through a conduction band. Electrons and holes are created by radiation in the beginning, and these electrons move to the trap through the conduction band. These holes move to the recombination center through a valence band. The ratio of the electrons allocated to each trap differs with the recombination probability and these values also relevant to the process of luminescence. Accordingly, the glow curve can be interpreted by taking the rate of electron–hole pairs created by ionizing radiation as a unique initial condition. This method differs from the conventional method of interpreting the measured glow curve with the initial electron concentration allocated to each trap at the end of irradiation. A program using the Visual Studio's C# subsystem was made to realize such a developed algorithm. To verify this algorithm it was applied to LiF:Mg,Cu,Si. The TL glow curve was deconvoluted with a model of five traps, one deep trap and one recombination center (RC).

Lumped parameter models for describing dynamics of the plasma channel in a parallel-plate plasma gun are compared with the experimental results obtained from two plasma guns with different rail geometries. Comparison between the experiments and the numerical calculations reveals that the lumped parameter models can be utilized to describe the dynamic motion of the plasma channel quite well. Parametric study shows that minimizing the line inductance and increasing the charging voltage on a capacitor as well as minimizing the gas injection time for reducing the mass of the plasma channel are the key factors to increase the flow velocity of the plasma jet ejected from the plasma gun.

Thermoluminescence (TL) glow curves of LiF:Mg,Cu,Si were deconvoluted with the introduction of enhanced physical model which envisages that both electrons and holes, produced by ionization radiation and trapped at the respective traps, can be thermally released into the conduction and the valence band, respectively and the holes may also radiatively recombine with electrons at the electron recombination centers. The model is more generalized than the ordinary trap interaction model which only permits the traffic of electrons through the conduction band. An effective numerical analysis method was developed to calculate the glow curve to be compatible with the measured curves. The validity of the numerical method was verified through artificially generated TL glow curves for a wide range of trap parameters. In order to identify TL kinetics of LiF:Mg,Cu,Si with higher accuracy, its glow curves were deconvoluted for two more generalized models, namely, the Schon–Klasens model and the Chen–Pagonis–Lawless model as well as the ordinary trap interactive model. The parameters in the more generalized multi-trap multi-recombination center (MTMR) model were found to be consistent with the quasi-static approximation(QSA) method.

Electrical probe measurements are carried out at the scrape-off-layer (SOL) and divertor regions in order to investigate the characteristics of edge plasmas during H-mode discharges in the Korea Superconducting Tokamak Advanced Research (KSTAR) device. Radial profiles of plasma parameters such as electron temperature Te, plasma density ne, and parallel flow velocity v‖ are measured by using a fast reciprocating Langmuir probe assembly (FRLPA) at the SOL region. From the FRLPA measurements, it is found that the decay length of temperature λTe and that of density λne are 2 ∼ 4 cm and 1 ∼ 3 cm, respectively. The magnitude of v‖ near the last closed flux surface (LCFS) is 4 ∼ 15 km/s. The radial flux due to edge turbulence at the SOL region is investigated by using spectra analysis on electrostatic fluctuation levels such as ion saturation current Ĩis and floating potential $ \tilde{\rm V}_f$ obtained from the FRLPA measurement. The value of the flux is estimated as ∼ 1020 particle m−2 s −1 near the LCFS. The poloidal distribution of the ion saturation current density jis is measured by fixed edge Langmuir probe array (ELPA) at the divertor region, and it is found that the positions of strike points from the ELPA measurement agree well with those reconstructed from the EFIT result using magnetic diagnostic data. From the spectrum analysis on the ELPA measurements at the divertor region during edge localized modes (ELMs) control in the H-mode discharges, it is observed that the magnitude of $ \tilde{\rm j}_{is}$(ω) near strike point decreases when the ELMs are suppressed or mitigated (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

[Purpose] To investigate the inter-rater and test-retest reliability of the sitting-rising test (SRT), the correlations of sitting-rising test scores with measures of strength, balance, community integration and quality of life, as well as the cut-off score which best discriminates people with chronic stroke from healthy older adults were investigated. [Subjects and Methods] Subjects with chronic stroke (n=30) and healthy older adults (n=30) were recruited. The study had a cross-sectional design, and was carried out in a university rehabilitation laboratory. Sitting-rising test performance was scored on two occasions. Other measurements included ankle dorsiflexor and plantarflexor strength, the Fugl-Meyer assessment, the Berg Balance Scale, the timed up and go test, the five times sit-to-stand test, the limits of stability test, and measures of quality of health and community integration. [Results] Sitting-rising test scores demonstrated good to excellent inter-rater and test-retest reliabilities (ICC=0.679 to 0.967). Sitting-rising test scores correlated significantly with ankle strength, but not with other test results. The sitting-rising test showed good sensitivity and specificity. A cut-off score of 7.8 best distinguished healthy older adults from stroke subjects. [Conclusions] The sitting-rising test is a reliable and sensitive test for assessing the quality of sitting and rising movements. Further studies with a larger sample are required to investigate the test's validity.

An efficient computer program has been developed to deconvolute thermoluminescence (TL) glow peaks and optically stimulated (OSL) curves by employing a method of the interactive trap model (ITM). The program is designed to be used easily on the MS Windows-based computer with a graphical user interface. This program could be used to analyze the TL glow curves by using the traditional first-order kinetics (1OK), second-order kinetics (2OK), general order kinetics (GOK), mixed order kinetics (MOK) and the general approximation (GA) method as well as ITM. The program was tested with the generated data and the experimental results of deconvoluted TL glow curves of LiF TLD-100 by assigning five interacting traps and one recombination center. A complete version with full functionalities of this program can be downloaded from the web site http://physica.gnu.ac.kr/TLanal .

Preliminary results of an attempt to prepare LiAlO 2 material with high optically stimulated luminescence (OSL) sensitivity are reported. LiAlO 2 was prepared by melting a stoichiometric mixture of Li 2 CO 3 and Al 2 O 3 powders in a RF heating furnace. CW-OSL signal as recorded on Risoe TL/OSL reader using blue (470 nm) stimulation was found to be up to 16 times of that of Al 2 O 3 :C. The promising characteristics of LiAlO 2 , open up a possibility of an improved material not only for passive dosimetry of mixed fields of neutron and gamma rays but also for online measurements and dose mapping/imaging applications.

Design and performance test results of a newly developed optically stimulated luminescence (OSL) measurement system are presented in this paper. Generally, different types of optical filters are used in OSL reader system to minimize the interference of the stimulation light in the OSL signal. For optically stimulation of , we have arrived at an optimal combination of the filters, i.e., GG420 filter for filtering the stimulating light source, and a combined UG11 and BG39 filter at the detecting window (PMT). By using a high luminance blue LED (Luxeon V), sufficient luminous intensity could be obtained for optically stimulation. By using various control boards, the OSL reader device was successfully interfaced with a personal computer. A software was developed to deliver required commands to operate the OSL reader by using the LabView program (National Instruments, Inc.). In order to evaluate the reliability and the reproducibility of newly designed-OSL reader. Performance testing of the OSL reader was carried out for OSL efficiency, OSL decay curve and signal to noise ratio of the standard OSL material. It was found to be comparable with that of commercial Riso reader system.

The most of the algorithms reported on the deconvolution of the OSL/TL glow curve is basically based on the one trap one recombination center (OTOR) model. In the OTOR model, each individual trap is considered to be independent with each other (mutually exclusive with each other), and the total glow curve is produced solely by the summation of the glow peaks generated from the luminescence emitted by the electrons in one individual trap when transferring to other trap(s). Therefore, there could be a major difference between the model and real physical process of the OSL/TL mechanism. Because the electrons being excited to be in the conduction band barely have past recollection of the original traps, it is widely believed that electrons in one trap can be easily transferred to other trap via the conduction band. Particularly in case of the OSL, the effects of mutual interactions among the traps could be more dominant than those in case of the TL. An algorithm, which can be used to numerically analyze the OSL/TL curves with reflecting the mutual interactions among the individual traps via the conduction band, is developed. This algorithm is able to promptly generate the glow curves for a system with numerous electron traps and recombination centers. Thus, the algorithm can be used to effectively deconvolute the glow curve of a given measurement data.

The LiF:Mg,Cu,Si thermoluminescence materials, recently developed at the laboratory, gain uprising popularity because the materials show several outstanding performance results such as high sensitivities for gamma radiation, flat energy responses with little fluctuation for photons, linear responses over the wide ranges of radiation doses and few residual electrons trapped in the holes. In this study, we investigated the impacts of the Mg concentration and the final thermal treatment conditions on the glow curve structure of LiF:Mg,Cu,Si material to enhance the ratio of high-temperature peak to main peak for the extended application of the two peaks in the high LET radiation dosimetry and in the high-temperature environment. Change in Mg concentration did not affect significantly the ratio of TL responses of high and main dosimetric glow peaks. With Mg concentration in the range from 0.35 to 0.45 mol% and a thermal treatment of 10 min in the range from 400 °C to 440 °C followed by the thermal treatment at 260 °C for 10 min (dual-step thermal treatment) resulted in the highest value of the ratio of TL response of high and main dosimetric glow peaks.

H-beams set up between columns are widely used to support building slabs. However, H-beams have fixed joints and the bending moment at both ends of the beam under uniformly distributed load is twice as great as the moment at its center. Because beam design is based on ultimate moment, its depth gets to be larger, which leads to the problem of smaller available space on each floor. If the ends of H-beam which are vulnerable to ultimate bending moment are additionally reinforced, beam design based on the bending moment at beam center is feasible. In this study, 4 specimens were fabricated for structural experiment with variables of the purpose of end-reinforcing steel plates, bar reinforcement and load transfer method in order to analyze the structural performance of end-reinforced steel frame beams (hereinafter Eco-girder system).

Thermoluminescence (TL) in LiF was found to depend on the use of proper combination of the dopant ions and the optimised preparation procedure. LiF doped with Mg,Cu,Si exhibited high TL sensitivity (55 times that of TLD-100 LiF:Mg,Ti) and insignificant higher temperature glow peak leading to negligible residual TL signal. The occurrence of the dosimetric peak in LiF was found to be a strong function of Mg dopant. The peak temperature and the TL emission spectra of dosimetric glow peak in all samples having Mg, Cu were always found to be the same irrespective of the third dopant which influenced only the intensity of TL emission spectrum. The emission band peaking at 385 nm was assigned to Cu.

A new method to analyze the thermoluminescence (TL) glow curve has been presented. It has been shown that this method is efficient and fast in generating the TL glow curves and can be adopted in a numerical curve fitting for obtaining the relevant TL parameters of a given TL glow curve data. This new method is based on a general approximation (GA) which assumes only that the concentration of the electrons in the conduction band is negligible when compared with the concentration of the electrons in the traps. The GA method has been tested against the reference glow curve data which was generated by the full iteration method without any prior approximation in the one-trap-one-recombination-centre model. By finding the best fit between the reference data and the curves generated by the GA method, the values of the kinetics parameters have been determined. Also, the general order kinetics (GOK) and the peak shape method have been examined. The fitted values of the activation energy and the initial concentration of electron by the GA method match reasonably well with the original value.

Several thermal treatments were studied to improve the TL dosimetric characteristics of the newly developed and highly sensitive LiF:Mg,Cu,Si sintered discs. A treatment of 260 ∘ C for 10 min was found to be able to fully restore the TL sensitivity and glow curve structure of the dosimeters which were otherwise altered by heating to 300 ∘ C . A dual-step thermal treatment of 300 ∘ C for 10 min followed by 260 ∘ C for 10 min was found to be optimum and it also minimized the unwanted glow peaks at higher temperatures, thereby reducing the residual TL signal to about 0.025%. For the reuse, annealing treatment of 260 ∘ C for 10 min was found to cause no noticeable change in the TL sensitivity and glow curve structure for 30 cycles of anneal and readout. An effort was also made to understand the role of dual-step thermal treatment in the light of known conversion of Cu + and Cu 2 + and the changes in precipitates and defect complexes involving Mg, Cu, Si, O and OH ions and their dissolution in LiF by heating.

In this paper, some results of the study on the roles of the dopants in the LiF:Mg,Cu,Na,Si thermoluminescent (TL) material that was developed at the Korea Atomic Energy Research Institute for radiation protection are presented. Although there have been many studies to investigate the roles of the dopants in LiF:Mg,Cu,P TL material in the TL process, there are some discrepancies in the understanding of the roles of Cu and P between various researchers. In case of LiF:Mg,Cu,Na,Si TL material, there are a few studies on the roles of the dopants. Three kinds of samples in each of which one dopant is excluded, and the optimised sample, were prepared for this study. The measurements and analysis of the three-dimensional TL spectra, based on the temperature, wavelength and intensity, and the glow curves for those samples are used in this study. The results show that Mg plays a role in the trapping of the charge carriers and Cu plays a role in the luminescence recombination process; however, the effect of Na and Si on the glow curve structure and the TL emission spectra is much less than that of Mg and Cu. It is considered that Na and Si each plays a role in the improvement of the luminescence efficiency.

A quick and efficient computer program was developed in order to resolve the peaks from the thermoluminescence (TL) glow curve. The program was designed to be easily used on any MS Windows-based computer with a graphical user interface. In this program, a new method based on the general one-trap TL equation was adopted to analyse the TL glow curve with the traditional first-order, second-order and general-order kinetics model. The method described here, general approximation, generates TL glow peaks and interpolates the relevant TL parameters from the glow data. The program was tested with simulated and experimental TL glow data and the results were found to be adequate and reliable.

This study was designed to investigate the in vitro developmental ability and apoptosis of bovine embryos nuclear- transferred (NT) with frozen-thawed or cooled donor cells. Cultured adult bovine ear cells were used as donor cells after sub-culturing to confluence (CC), cooling to 4°C for 48 h, or freezing-thawing (FT). Apoptotic cells in blastocysts were evaluated for apoptosis by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method. Fusion, cleavage and blastocyst rates were 69.0 (167/242), 68.8 (115/167), and 29.9 (50/167) with CC cells, 70.4 (88/125), 69.3 (61/88), and 29.6 (26/88) with cooled cells and 66.1 (117/177), 70.1 (82/117), and 13.7 (16/117) with FT cells, respectively. Blastocyst rates of NT embryos derived from FT cells were significantly lower than those from CC or cooled cells (p

A small plasma gun with parallel-plate configuration is fabricated to generate a bunch of plasma which is similar to ELM (edge localized mode) plasma, by taking advantages of its simplicity and cost-effectiveness. Prior to explore how to control the ELM-like plasma so as to relieve heat load on the divertor target, characteristics of a plasma jet ejected from the plasma gun are investigated using a quadruple Langmuir probe which is appropriate for measuring rapidly varying plasma parameters such as electron density, temperature, and ion velocity at the same time. The plasma density and ion velocity measured at 112 mm away from the exit are 3 × 1019 m−3 and 11 km/s, respectively, which seem to be suitable for investigating next step research on the control of ELM-like plasma using various methods such as electromagnetic waves and high-voltage pulses. Also, the quadruple Langmuir probe is proven to be adequate for use in such experiments.

The glow curve structures for LiF:Mg,Cu,Na,Si TL detectors with various dopant concentrations and sintering temperatures were investigated for the improvement of the glow curve structure and sensitivity of the TL detector. The dopant concentrations were varied over the following ranges: Mg (0– 0.25 mol % ), Cu (0– 0.07 mol % ), Na and Si (0– 1.5 mol % ). With increasing Cu concentration, the intensity of the main peak was intensified and reached a maximum at a concentration of 0.05 mol % . The high-temperature peak was reduced. The dependency of the main peak intensity on the Mg concentration exhibits a sharp maximum at 0.2 mol % . The intensity of the high-temperature peak tends to rise slightly with increasing Mg concentration. It was found that the optimum concentrations of the dopants in the LiF:Mg,Cu,Na,Si TL material are Mg: 0.2 mol % , Cu: 0.05 mol % , Na and Si: 0.9 mol % . The dependency of the main peak intensity on sintering temperature exhibits a very sharp maximum at 830°C. The high-temperature peak was rapidly reduced after 825°C.

Several thermal treatments in the temperature range from 270 °C to 320 °C (each of 10 min) were tested as a final preparation procedure of LiF:Mg,Cu,Si to improve the protocol of TL readout with less residual signal for the LiF:Mg,Cu,Si TLD. This high sensitivity LiF:Mg,Cu,Si TLD exhibited thermal stability much better than that of the well known LiF:Mg,Cu,P. For LiF:Mg,Cu,Si, a readout temperature up to 300 °C did not affect the TL sensitivity and glow curve structure for 12 cycles of exposure and readout following an initial thermal treatment at 295 °C for 10 min. The residual TL signal also remained negligible.

A new computerized glow curve deconvolution (CGCD) algorithm for thermoluminescence(TL) and optically stimulated luminescence (OSL) is presented. The proposed approach can be adopted in a numerical curve fitting for obtaining the relevant trapping parameters of a set of glow data taken with both thermal and optical stimulation. This method is based on the one trap one recombination center (OTOR) model with minimal simplifying assumptions. To demonstrate the ability of the method, a new computer program has been developed and tested with some synthetic OSL data.

The WA95/CHORUS experiment at CERN is a dedicated nu(mu)-nu(tau) oscillation search experiment. Using the wide band neutrino beam of the CERN-SPS accelerator, with an exposure of 2.4 X 10(19) protons on the target, this experiment will explore the domain of small mixing angles down to sin(2) 2 theta(mu tau) approximate to 3 X 10(-4) for mass differences Delta m(2) > 1 eV(2), more than one order of magnitude better than the current limits. The conceptual design of the CHORUS experiment and data on the detector performances are reported.

A search for charm hadron decays into two muons plus one or more hadrons has been carried out using a hybrid emulsion spectrometer. This technique is sensitive to modes with missing neutrals, e.g. π0μ+μ− and ϱ±μ+μ−, as well as to constrained modes having visible invariant masses equal to those of charm states. No evidence for any such decays has been found, which allows upper limits at the 90% confidence level as low as 1.8 × 10−4 to be placed on the branching fractions for charm-changing neutral-current and lepton-number violating decay modes.

In this paper we discuss the various types of realization ofsuq (N+1) algebra. We review theq-deformed Jordan-Schwinger realization forsuq (N+1) algebra. We introduce the general framework for obtaining theq-deformed. Holstein-Primakoff transformation andq-deformed action angle bosonization ofsuq (N+1) algebra.

The relative branching fraction RK = Γ(D0 → K−μ+v)/Γ(D0 → μ−X) has been measured by Fermilab experiment E653, using D0 mesons produced by 600 GeV π−. The semimuonic decay sample of 232 events was identified by the decay chain D ∗+ → D 0 π + , D 0 → μ + h − X , where h is a hadron. The Kμv component was extracted from the joint distribution of these events in the D0 decay variables Mmin and pTh. We find RK = 0.472 ± 0.051 (stat) ± 0.040 (sys), and use a world average of the D0 → Klv branching fraction to obtain the D0 inclusive semimuonic branching fraction B(D0 → μ+X) = (7.67 ± 1.13)%.

In this paper we use the generalized deformed algebra to construct the realization of the generalized deformedsu(2) algebra.

A new method, called graphic scanning, was developed by the Nagoya University Group for emulsion analysis in a hybrid experiment. This method enhances both speed and reliability of emulsion analysis. Details of the application of this technique to the analysis of Fermilab experiment E653 are described.

We report the first observation of the Cabibo disfavored semileptonic decay mode D+ → ρ(770)0 μ+v and measure its decay rate relative to the Cabibbo favored mode D + → K ∗ (892) 0 μ + v to be Λ(D + → ρ(770) 0 μ + v Λ(D + → K ∗ (892) 0 μ + v) = 0.044 0.031 −0.025 ( stat. ) ± 0.014 ( syst. ) . The results are compared to theoretical predictions and to previous experimental upper limits.

A search for charm production in the coherent diffractive dissociation reaction pSi→XSi was carried out for the modes D0→K−π+, D0→K−π+π+π−, and D+→K−π+π+. No charm signals were observed, and the 90% confidence level upper limit for coherent charm pair production was determined to be 26 μb per silicon nucleus. The results are interpreted as an upper limit of 0.2% on the amount of intrinsic charm in the proton.

Upper limits at the 90% confidence level are presented for four- and five-prong semimuonic decays of charm mesons. From a study of four-prong vertices we find B ( D 0 → K − π + π − μ + ν )/ B ( D 0 → K − μ + ν ) B (D 0 → ( K ∗ (892)π) − μ + ν)/B(D 0 → K − μ + ν) . The five-prong vertices yield the result B ( D S + → η ′ μ + ν ) / B ( D S + → φμ + ν )

We present a study of the Cabibbo-allowed semimuonic decay modes of the DS+ produced in 600 GeV c π − -emulsion interactions. From a signal of 18.7±4.9−0.7+0.4 events in the DS+ → oμ+υ channel, the product of production cross section and partial width is measured with respect to that for D + → K ∗0 μ + υ to be ( σ(D S + ) σ(D + )) . (Λ(D S + → oμ + ν)Λ(D + → K ∗0 μ + ν)) = 0.56 ± 0.14 ± 0.12. The form factor ratios in the decay, obtained by fitting to the decay angles and q2, are A 2 (0) 1 (0) = 2.1 −0.5 +0.6 ± 0.2 and V (0) A 1 (0) = 2.3 −0.9 +1.1 ± 0.4 , where A1 (0) and A2 (0) are the axial vector form factors and V(0) is the vector form factor, evaluated at q2 = 0. The first observation of DS+ → (ημ+υ + η'μ+υ) is also reported, and Γ (D S + → (ημ + υ + η'μ + υ)) Γ (D S + → oμ + υ) is determined to be 3.9 ± 1.6.

We report on the production characteristics and total cross section for 9 beauty hadron pairs produced by a 600 GeV/ c π − beam, the first such information in this energy region. The events were detected in the hybrid emulsion spectrometer of Fermilab Experiment E653. The measured pair cross section for all χ F , assuming linear A dependence, is 33±11 (stat.)±6(syst.) nb/nucleon. Fits of the inclusive single-hadron production distribution to the forms d σ d χ F ∝ (1−|χ F −χ 0 |) n and d σ d p T 2 ∝ exp (−bp t 2 ) give n=5.0 −2.1−1.7 +2.7+1.7 , χ 0 =0.06 −0.07−0.03 +0.06+0.02 , and b=0.13 −0.04−0.02 +0.05+0.02 ( GeV /c −2 . .The pairs tend to be produced back-to-back.

The branching ratio for the decay mode D + → K ∗0 μ + ν has been measured with two methods. The first uses D0→K−μ+ν for normalization, and yields the result B( D + → K ∗0 μ + ν)=(3.25±0.71±0.75)% . From this method we also obtain the direct measurement Γ( D + → K ∗0 μ + ν)/Γ( D 0 → K − μ + ν)=0.43±0.09±0.09 . The second method uses the mode D+→K−π+π+ for normalization and yields B( D + → K ∗0 μ + ν)=(4.18±0.66±0.96)% . Combining the results of the two methods yields B( D + → K ∗0 μ + ν)=(3.57±0.96)% .

We present total and differential cross sections for charm mesons produced in 600 GeV/c π- emulsion interactions. Fits to d2σ/dxF dpT2∞ (1−|xF|)nexp (-bpT2) for 676 electronically reconstructed D mesons with xF>0 give n=4.25±0.24 (stat.)±0.23 (syst.) and b=0.76±0.03±0.03 (GeV/c)-2. The total inclusive D+ and D0 cross sections are σ(π-N→D±; xF>0) = 8.66±0.46±1.96μb nucleon and σ(π - N→D 0 D 0 ; x F >0)=22.05±1.37±4.82μb nucleonk, where a linear dependence on the mean atomic weight of the target is assumed. These results are compared to next-to-leading order QCD predictions.