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In this study, the mechanical and thermophysical properties of carbon fiber-reinforced polyethersulfone are investigated. To enhance the interfacial interaction between carbon fibers and the polymer matrix, the surface modification of carbon fibers by thermal oxidation is conducted. By means of AFM and X-ray spectroscopy, it is determined that surface modification changes the morphology and chemical composition of carbon fibers. It is shown that surface modification dramatically increases the mechanical properties of the composites. Thus, flexural strength and the E-modulus of the composites reinforced with modified fibers reached approximately 962 MPa and 60 GPa, respectively, compared with approximately 600 MPa and 50 GPa for the composites reinforced with the initial ones. The heat deflection temperatures of the composites reinforced with the initial and modified fibers were measured. It is shown that composites reinforced with modified fibers lose their stability at temperatures of about 211 °C, which correlates with the glass transition temperature of the PES matrix. The thermal conductivity of the composites with different fiber content is investigated in two directions: in-plane and transverse to layers of carbon fibers. The obtained composites had a relatively high realization of the thermal conductive properties of carbon fibers, up to 55–60%.

We explore the photoproduction mechanisms for charged and neutral pion pairs off a heavy nucleus at threshold. We calculate the production of charged pairs in the Coulomb field of the nucleus in the Born approximation using explicit expressions for the differential cross sections and their connection with the total cross-section. The production of sigma mesons at threshold and their subsequent decay into pions is an important mechanism and is investigated quantitatively in a framework that can be used for both charged and neutral pions. Sigma mesons can be produced via electromagnetic (photon exchange) or strong (omega exchange) interactions. For neutral pions, another important production mechanism consists of the two-step process where charged pions are produced first and then charge exchange into two neutral pions. Differential and total cross sections are computed for each production mechanism.

The article clarifies the concept of in-house interview as an interview of employees or job candidates, organized by the security service of a private company, identifies the types of in-house interview, clarifies the concept of confession. The two-stage model of inquest and some indicators of lying, which are used by the authors during the in-house interview, are described. The indicators correlating with lying in the course of service interview - the latent verbal aggression, lying strategies, presence of textual bridges and lacunas, separate elements of mimic and kinetic behavior are offered. The two-step model of Reed’s inquest, known as “Reed’s Nine Steps to Getting a Confession”; the approach of domestic psychologist L. B. Filonov, the authors’ approach to organizing the process of getting a confession within a service interview are partially described. The psychological mechanisms that make it possible to obtain previously unknown information during in-house interviews, which can be used in any kind of interviews and interrogations, are considered.

Recently collated scientific data on the management of C1 clinical class of chronic venous disorders; wide prevalence of the disease and high variability amongst medical practitioners in relation to managing this category of patients and absence of any regulatory documents has prompted the development of clinical guidelines for the treatment of patients with reticular varicose veins and telangiectasias of the lower extremities and various parts of the body. These guidelines have been developed by a self-regulated organization Association “The National College of Phlebology”. The purpose of the de novo guidelines is to systematize the existing evidence and offer minimal standards of care for chronic venous disorders in C1 patients.

Elastic electron–proton scattering (e–p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, rp. In 2010, a new method using muonic hydrogen atoms1 found a substantial discrepancy compared with previous results2, which became known as the ‘proton radius puzzle’. Despite experimental and theoretical efforts, the puzzle remains unresolved. In fact, there is a discrepancy between the two most recent spectroscopic measurements conducted on ordinary hydrogen3,4. Here we report on the proton charge radius experiment at Jefferson Laboratory (PRad), a high-precision e–p experiment that was established after the discrepancy was identified. We used a magnetic-spectrometer-free method along with a windowless hydrogen gas target, which overcame several limitations of previous e–p experiments and enabled measurements at very small forward-scattering angles. Our result, rp = 0.831 ± 0.007stat ± 0.012syst femtometres, is smaller than the most recent high-precision e–p measurement5 and 2.7 standard deviations smaller than the average of all e–p experimental results6. The smaller rp we have now measured supports the value found by two previous muonic hydrogen experiments1,7. In addition, our finding agrees with the revised value (announced in 2019) for the Rydberg constant8—one of the most accurately evaluated fundamental constants in physics. A magnetic-spectrometer-free method for electron–proton scattering data reveals a proton charge radius 2.7 standard deviations smaller than the currently accepted value from electron–proton scattering, yet consistent with other recent experiments.

Aim. The purpose is to determine the hazard class and hydraulic activity of the blast-furnace slag fractions and substantiate the way of their utilization. The study deals with the blast furnace slags from Zaporizhstal, Dnieper Metallurgical Combine (DMC), ArcelorMittal Kryvyi Rig, Illich Iron & Steel Works (Mariupol Metallurgical Combine - MMC) and Alchevsk MC (AMC). Methods. The mineral composition of the slags was determined using X-ray phase analysis on a Siemens D500 diffractometer. The elemental composition of the slag fractions was determined by electron probe microanalysis on a JSM-6390 LV scanning electron microscope with an X-ray microanalysis system. The hazard class was determined by calculating the toxicity indices. Results. In the fractions of blast furnace slags, silicate minerals of three systems were found: CaO‒SiO2, CaO‒Al2O3‒SiO2 and СаО‒MgO‒SiO2. The hydraulic activity of slags is quite high, it is determined by the mass fraction of hydraulically active minerals: bredigite, larnite, akermanite, pseudowollastonite; by titrimetry according to the amount of absorbed lime and the content of unbound CaO. The impurity elements S, F, Cl, P, Mn, and Ti were found in slags. The calculation of the total hazard indices showed that all the studied fractions of blast furnace slags belong to hazard class III (moderately hazardous). Conclusions. The analyzed slag fractions can be used as sorbents in the treatment of waste water and secondary raw materials at roasting and hydration when producing binders, which ensures a decrease in the content of toxic components in the finished product to comply with hazard class IV., Цель. Определить класс опасности и гидравлическую активность фракций доменных шлаков и обосновать направление их утилизации. Исследование касается доменных шлаков Запорожстали, Днепровского металлургического комбината (ДМК), АрселорМиттал Кривой Рог, Мариупольского МК и Алчевского МК. Методы. Минеральный состав шлаков определяли с помощью рентгенофазового анализа на дифрактометре Siemens D500. Элементный состав фракций шлаков определяли электронно-зондовым микроанализом на сканирующем электронном микроскопе JSM-6390 LV с системой микрорентгеновского анализа. Класс опасности определяли при расчете индексов токсичности и суммарных индексов опасности. Результаты. Во фракциях доменных шлаков обнаружены силикатные минералы трех систем: CaO‒SiO2, CaO‒Al2O3‒SiO2 и СаО‒MgO‒SiO2. Гидравлическая активность шлаков достаточно высока, она определена по массовой доле гидравлически активных минералов: бредигита, ларнита, окерманита, псведоволластонита; титриметрически по количеству поглощенной извести и содержанию несвязанной СаО. Как элементы-примеси в шлаках найдены S, F, Cl, P, Mn и Ti. Все исследованные фракции доменных шлаков относятся к III классу опасности (умеренно опасные). Выводы. Исследованные шлаковые фракции могут использоваться в качестве сорбентов при очистке сточных вод и вторичного сырья в производстве вяжущих материалов при обжиге и гидратации, что обеспечивает снижение содержания токсичных компонентов в готовой продукции до соответствия IV классу опасности., Мета. Визначити клас небезпеки і гідравлічну активність фракцій доменних шлаків і обґрунтувати напрям їх утилізації. Дослідження стосується доменних шлаків Запоріжсталі, Дніпровського металургійного комбінату (ДМК), АрселорМіттал Кривий Ріг, Маріупольського МК і Алчевського МК. Методи. Мінеральний склад шлаків визначали за допомогою рентгенофазового аналізу на дифрактометрі Siemens D500. Елементний склад фракцій шлаків визначали електронно-зондовим мікроаналізом на скануючому електронному мікроскопі JSM-6390 LV з системою мікрорентгеновского аналізу. Клас небезпеки визначали при розрахунку індексів токсичності і сумарних індексів небезпеки. Результати. У фракціях доменних шлаків виявлені силікатні мінерали трьох систем: CaO‒SiO2, CaO‒Al2O3‒SiO2 і СаО‒MgO‒SiO2. Гідравлічна активність шлаків досить висока, вона визначена по масовій частці гідравлічно активних мінералів: бредигіта, ларніта, окерманіта, псведоволастоніта; титруванням за кількістю поглиненого вапна і вмістом незв'язаного СаО. Як елементи-домішки в шлаках знайдені S, F, Cl, P, Mn і Ti. Всі досліджені фракції доменних шлаків відносяться до III класу небезпеки (помірно небезпечні). Висновки. Досліджені шлакові фракції можуть використовуватися в якості сорбентів при очищенні стічних вод і вторинної сировини у виробництві в'яжучих матеріалів при випалюванні і гідратації, що забезпечує зниження вмісту токсичних компонентів у готовій продукції до відповідності IV класу небезпеки.

We report measurements of the photon beam asymmetry Σ for the reaction γp→K+Σ0 (1193) using the GlueX spectrometer in Hall D at Jefferson Lab. Data were collected by using a linearly polarized photon beam in the energy range of 8.2–8.8 GeV incident on a liquid hydrogen target. The beam asymmetry Σ was measured as a function of the Mandelstam variable t , and a single value of Σ was extracted for events produced in the u channel. These are the first exclusive measurements of the photon beam asymmetry Σ for the reaction in this energy range. For the t channel, the measured beam asymmetry is close to unity over the t range studied, − t = ( 0.1 – 1.4 ) ( GeV / c ) 2 , with an average value of Σ = 1.00 ± 0.05 . This agrees with theoretical models that describe the reaction via the natural-parity exchange of the K ∗ (892) Regge trajectory. A value of Σ = 0.41 ± 0.09 is obtained for the u channel integrated up to − u = 2.0 ( GeV / c ) 2 .

Testing the chiral anomaly Pi mesons, also known as pions, consist of a quark and an antiquark and are extremely unstable. Neutral pions have a lifetime of only ∼80 attoseconds, decaying into two photons. Quantum chromodynamics (QCD), the theory of quarks and gluons, predicts this decay and the associated lifetime using the mechanism of broken chiral symmetry—the so-called chiral anomaly. Measuring the lifetime to high precision then provides a benchmark for theories that aim to improve on this original prediction. Larin et al. measured this lifetime with an uncertainty that was half that of the previous most precise result (see the Perspective by Meyer). The measured value was consistent with the original QCD prediction and less consistent with other theoretical approaches. Science , this issue p. 506 ; see also p. 469

We report on the measurement of the beam asymmetry Σ for the reactions → γ p → p η and → γ p → p η ′ from the GlueX experiment using an 8.2–8.8-GeV linearly polarized tagged photon beam incident on a liquid hydrogen target in Hall D at Jefferson Laboratory. These measurements are made as a function of momentum transfer − t with significantly higher statistical precision than our earlier η measurements and are the first measurements of η ′ in this energy range. We compare the results to theoretical predictions based on t -channel quasiparticle exchange. We also compare the ratio of Σ η to Σ η ′ to these models as this ratio is predicted to be sensitive to the amount of s ¯ s exchange in the production. We find that photoproduction of both η and η ′ is dominated by natural parity exchange with little dependence on − t .

The cross section of atomic electron Compton scattering $\gamma + e \rightarrow \gamma^\prime + e^\prime $ was measured in the 4.40--5.475 GeV photon beam energy region by the {\em PrimEx} collaboration at Jefferson Lab with an accuracy of 2\% and less. The results are consistent with theoretical predictions that include next-to-leading order radiative corrections. The measurements provide the first high precision test of this elementary QED process at beam energies greater than 0.1 GeV., Comment: 6 pages, 4 figures

Elastic electron-proton scattering (e-p) and the spectroscopy of hydrogen atoms are the two methods traditionally used to determine the proton charge radius, r

We report on the measurement of the γp→J/ψp cross section from Eγ=11.8 GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39 GeV-2 at 10.7 GeV average energy. The LHCb pentaquark candidates Pc+ can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(Pc+→J/ψp) and cross sections σ(γp→Pc+)×B(Pc+→J/ψp). © 2019 American Physical Society.

The Jefferson Laboratory PrimEx Collaboration has developed and implemented a method to control the tagged photon flux in photoprocluction experiments at the 1% level over the photon energy range from 4.9 to 5.5 GeV. This method has been successfully implemented in a high precision measurement of the neutral pion lifetime. Here, we outline the experimental equipment and the analysis techniques used to accomplish this. These include the use of a total absorption counter for absolute flux calibration, a pair spectrometer for online relative flux monitoring, and a new method for post-bremsstrahlung electron counting. (C) 2014 Elsevier B.V. All rights reserved.

The results of studying the variability of the geochemical parameters of the layers of the Sartamskii upland peatbog in the south of Tyumen oblast based on the radiocarbon time scale are given. Four basic types of peat and stages of peat deposits formation in the Holocene are distinguished: the organomineral layer of the sediments in a paleolake (up to 5065 ± 60 years ago), the low moor layer (4300–4900 years ago), the transitional layer (3100–4300 years ago), and the high moor peat (250–3100 years ago). The upper peat layer (last 200–300 years) significantly differs from its main portion; in particular, it is characterized by an increased ash content and the accumulation of a number of elements. The relationship between the various characteristics of the deposit is analyzed using principal component analysis, and the conditions of the formation of the peat deposit in different time periods are estimated, including the climatic conditions (in relative units). The anthropogenic signal of the accumulation of some elements in wetland systems is identified.

Problem. Industrial waste accumulating in dumps, in many cases, have valuable technical properties, so they can be considered as secondary resources. Тhe study of the properties and modification of slags under various conditions requires an integrated approach, including different analysis. Goal . Based on the selected experimental methods to justify the resource value of Zaporizhstal waste blast furnace slag. Methodology . The methods of the study were X-ray diffraction, gamma-spectrometry, spectrographic analysis and electron-probe microanalysis. Results. X-ray phase analysis revealed the minerals of the blast-furnace slags in the crystalline state: rankinite 3CaO∙2SiO 2 , quartz SiO 2 , gehlenite 2CaO∙Al 2 O 3 ∙SiO 2 , bredigit α-2CaO∙SiO 2 , okermanit 2CaO∙MgO∙2SiO 2 , pseudowollastonite α-CaO∙SiO 2 . The mass fraction of the glassy component is calculated, which is half the mass of Zaporizhstal blast furnace slag. The elemental composition of the slag, determined by electron probe microanalysis, made it possible to characterize its fractions from the standpoint of toxicity. The elements potassium, sodium, sulfur, chlorine, copper and titanium, which are not included in the composition of minerals, were recorded using a scanning electron microscope, which gives grounds for assuming that they are sorbed by the surface of mineral particles. Micrographs of the surface of the particles of blast furnace slag indicate a high degree of loosening with the presence of needle-like and plate-like crystals, which determines the sorption properties of the slag. The maximum content of potassium, sodium and titanium is characteristic of the 2.5–5 mm fraction. Slag contains an insignificant amount (

The pattern of the electrochemical ionization and passivation of Cu 62 Zn brass in chloride solutions with different compositions is studied. The electrochemical dissolution of Cu 62 Zn alloy is shown to be controlled by ionization of the copper component in the alloy. The dissolution selectivity of the brass Cu 62 Zn components and the modification of the surface of the alloy during electrochemical etching in chloride solutions are studied. The uniform electrochemical dissolution of α-brass in an acid medium was found to occur in the presence of chlorine ions and an Fe3+ oxidizing agent.

Osteomyelitis of skull belongs to the rare necrotic infections of bones. Its distribution is about1.5% from osteomyelitis of the flat bones. During last 10 years in Russian neuro-surgical literature are no data covering this issue. Foreign publications review observations about single cases. This work describes clinical case of successful surgical treatment of frontal bone osteomyelitis, complicated by abscess in forehead part of brain.

The chronic pelvic pain in women is a problem more often is being discussed by gynecologists and urologists. In the neurological practice pelvic pain occur quite rarely. Conservative treatment of chronic pelvic pain is little effective. The case history of successful relief of chronic neurogenic pelvis pain using a permanent electrostimulation of the sacral plexus is described.

The paper reports geochemical parameters of units in a peat bed in a raised bog in the southern Tyumen territory. Based on radiocarbon dates and the variability of the geochemical data, the following four evolutionary stages of the bed in the Holocene are distinguished: an ancient lake (5600–5750 years B.P.), low-land-bog peat (4550–5600 years B.P.), transitional-type peat (4200–4550 years B.P.), raised-bog peat. The major-component technique was applied to analyze relations between various parameters of the bed and evaluate the variations in the condition under which the bog evolved with time, including climatic conditions (in relative units). An anthropogenic signal of the accumulation of certain metals in bog systems is distinguished.

We report the first observation of two Cabibbo-suppressed decay modes, Ξ c + → Σ + π − π + and Ξ c + → Σ − π + π + . We observe 59 ± 14 over a background of 87, and 22 ± 8 over a background of 13 events, respectively, for the signals. The data were accumulated using the SELEX spectrometer during the 1996–1997 fixed target run at Fermilab, chiefly from a 600 GeV / c Σ − beam. The branching ratios of the decays relative to the Cabibbo-favored Ξ c + → Ξ − π + π + are measured to be B ( Ξ c + → Σ + π − π + ) / B ( Ξ c + → Ξ − π + π + ) = 0.48 ± 0.20 , and B ( Ξ c + → Σ − π + π + ) / B ( Ξ c + → Ξ − π + π + ) = 0.18 ± 0.09 , respectively. We also report branching ratios for the same decay modes of the Λ c + relative to Λ c + → p K − π + .

It was shown that the CuCl layers deposited on copper chemically and electrochemically from copper-ammonia solutions were different. The layer formed chemically was loose, and that formed on the anode, dense. During multilayer copper passivation, the chemically deposited CuCl layer interfered with the formation of electrochemical CuCl and Cu2O layers.

A setup is developed at the Institute for Theoretical and Experimental Physics for studying cumulative processes in hA and AA interactions with photon and π0-meson production in the central region of rapidities at high transverse momenta. Lead glass calorimeters and a charged particle rejection system are the main components of the setup. A fast trigger for a high-energy cumulative particle, based on detection of Cherenkov radiation in the lead glasses, is realized in the setup.

One of the main trends in the development of materials for the body and other parts of automobiles is the greater use of high-strength steels, this being done in order to make the vehicle safer and lighter. The need for this change stems from the continual tightening of standards on tailpipe emissions. The largest metallurgical companies that presently make automobile sheet have been working with the main Russian automobile manufacturers to develop steels with improved commercial properties. This article presents results from studies conducted to optimize the technology used to make rolled products of high-strength, ultralow-carbon steels 01YuTB an 01YuPTB for the automotive industry. The optimized technology includes heat treatment in a continuous annealing furnace. Emphasis should be given to developing technical recommendations on how to optimally combine strength, stampability, and a guaranteed level of the BH-effect (BH2 ≥ 30–40 N/mm2) in the production of automobile sheet of strength class K180, as well as BH steels of strength class K220 or higher.

Artifacts observed in the indirect covariance NMR spectrum of HSQC-TOCSY data have recently been analyzed and a method for their elimination proposed. More recently, unsymmetrical covariance processing has been applied HSQC and HMBC spectral data to afford long-range carbon-carbon correlation information equivalent to that obtained from n, 1-, 1, n- and m,n-ADEQUATE spectra. We now wish to describe the results obtained through the application of unsymmetrical covariance processing of HSQC and COSY or TOCSY data, which affords the equivalent of HSQC-COSY and HSQC-TOCSY data in a fraction of the time required to record these spectra directly and with considerably higher sensitivity.

We observe a signal for the doubly charmed baryon Ξ c c + in the decay mode Ξ c c + → p D + K − to complement the previous reported decay Ξ c c + → Λ c + K − π + in data from SELEX, the charm hadroproduction experiment at Fermilab. In this new decay mode we observe an excess of 5.62 events over a combinatoric background estimated by event mixing to be 1.38 ± 0.13 events. The mixed background has Gaussian statistics, giving a signal significance of 4.8σ. The Poisson probability that a background fluctuation can produce the apparent signal is less than 6.4 × 10 −4 . The observed mass of this state is 3518 ± 3 MeV / c 2 , consistent with the published result. Averaging the two results gives a mass of 3518.7 ± 1.7 MeV / c 2 . The observation of this new weak decay mode confirms the previous SELEX suggestion that this state is a double charm baryon. The relative branching ratio for these two modes is 0.36 ± 0.21 .

Indirect covariance NMR offers an alternative method of extracting spin–spin connectivity information via the conversion of an indirect-detection heteronuclear shift-correlation data matrix to a homonuclear data matrix. Using an IDR (inverted direct response)-HSQC-TOCSY spectrum as a starting point for the indirect covariance processing, a spectrum that can be described as a carbon–carbon COSY experiment is obtained. These data are analogous to the autocorrelated 13C–13C double quantum INADEQUATE experiment except that the indirect covariance NMR spectrum establishes carbon–carbon connectivities only between contiguous protonated carbons. Cyclopentafuranone and the complex polynuclear heteroaromatic naphtho[2′,1′:5,6]-naphtho[2′,1′:4,5]thieno[2,3-c]quinoline are used as model compounds. The former is a straightforward example because of its well-resolved proton spectrum, while the latter, which has considerable resonance overlap in its congested proton spectrum, gives rise to two types of artifact responses that must be considered when using the indirect covariance NMR method. Copyright © 2005 John Wiley & Sons, Ltd.

Coherent Λπ− production on Pb of 600 GeV Σ− hyperons has been studied with the SELEX facility at Fermilab. Using the Primakoff formalism, we set a 90% CL upper limit on the radiative decay width Γ[Σ(1385)−→Σ−γ] s ≈1.385 GeV to be 56±16 μb.

The production of $D_s^-$ relative to $D_s^+$ as a function of $x_F $ with 600 GeV/c $\Sigma^-$ beam is measured in the interval $0.15 < x_F < 0.7$ by the SELEX (E781) experiment at Fermilab. The integrated charge asymmetries with 600 GeV/c $\Sigma^-$ beam ($0.53\pm0.06$) and $\pi^-$ beam ($0.06\pm0.11$) are also compared. The results show the $\Sigma^-$ beam fragments play a role in the production of $D_s^-$, as suggested by the leading quark model., Comment: 11 pages, 5 figures, submitted to Physics Letter B

The investigation of an inside local corrosion of a blast-furnace gas pipe is reported; the corrosivity of dust slurry is revealed. A version of galvanic cathodic protection with anodes made of an Al–Zn alloy is suggested. In laboratory conditions, it enables one to attain a protective effect of 85%.

We report on the measurement of the one-dimensional charged kaon correlation functions using 600~GeV/{\it c} $\Sigma^-$, $\pi^-$ and 540~GeV/{\it c} $p$ beams from the SELEX~(E781) experiment at the Fermilab Tevatron. $K^{\pm}K^{\pm}$ correlation functions are studied for three transverse pair momentum, $k_T$, ranges and parameterized by a Gaussian form. The emission source radii, $R$, and the correlation strength, $\lambda$, are extracted. The analysis shows a decrease of the source radii with increasing kaon transverse pair momentum for all beam types., Comment: 8 pages, 4 figures, 1 table

Evaluation of epidemic situation by non-poliomyelitis enterovirus infections in Krasnodar region in multi-year dynamics and characterization of clinical course of enterovirus serous meningitis in hospitalize patients.Retrospective analysis of non-poliomyelitis enterovirus infection epidemi process manifestations during 2002-2012 in Krasnodar region territory based on data of Center of Hygien and Epidemiology in Krasnodar Region.Clinical-epidemiologic characteristics of enterovirus infections in Krasnodar region are presented. Landscape ofenteroviruses isolated from the environment of some territories of the region and from the biological material of patients with various diseases is demonstrated. Clinical features ofenterovirus meningitis course are characterized.Enterovirus transmission b contact route was established to be the most frequent. A lack of pathognomonic symptoms and awareness o physicians of various specialties regarding diagnostics of this infection are the clinical problems of non-po liomyelitis enterovirus diseases.

The charge-exchange reaction K + Xe → K 0 pXeis investigated using the data of the DIANA experiment. The distribution of the pK 0 effective mass shows a promi- nent enhancement near 1538 MeV formed by nearly 80 events above the background, whose width is consistent with being entirely due to the experimental resolution. Under the selections based on a simulation of K + Xe collisions, the statistical signif- icance of the signal reaches 5.5�. We interpret this observation as strong evidence for formation of a pentaquark baryon with positive strangeness, � + (uudd¯), in the charge-exchange reaction K + n → K 0 p on a bound neutron. The mass of the � + baryon is measured as m(� + ) = 1538 ± 2 MeV. Using the ratio between the num- bers of resonant and non-resonant charge-exchange events in the peak region, the intrinsic width of this baryon resonance is determined as ( � + ) = 0.34±0.10 MeV.

Made available in DSpace on 2022-04-28T19:55:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2001-12-13 The σ- mean squared charge radius has been measured in the space-like Q2 range 0.035-0.105 GeV2/c2 by elastic scattering of a σ- beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain (rch2σ- = (0.61 ± 0.12(stat.) ± 0.09(syst.)) fm2. The proton and π- charge radii were measured as well and are consistent with results of other experiments. Our result agrees with the recently measured strong interaction radius of the σ-. © 2001 Elsevier Science B.V. All rights reserved. Ball State University, Muncie, IN 47306 Bogazici University, Bebek 80815 Istanbul Carnegie-Mellon University, Pittsburgh, PA 15213 Centro Brasiliero de Pesquisas Físicas, Rio de Janeiro Fermilab, Batavia, IL 60510 Institute for High Energy Physics, Protvino Institute of High Energy Physics, Beijing Institute of Theoretical and Experimental Physics, Moscow Max-Planck-Institut für Kernphysik, 69117 Heidelberg Moscow State University, Moscow Petersburg Nuclear Physics Institute, St. Petersburg Tel Aviv University, 69978 Ramat Aviv Universidad Autónoma de San Luis Potosó, San Luis Potosi Universidade Federal da Paraiba, Paraíba University of Bristol, Bristol BS8 1TL University of Iowa, IA City, IA 52242 University of Michigan-Flint, Flint, MI 48502 University of Rome 'La Sapienza' and INFN, Rome University of SãoPaulo, São Paulo University of Trieste and INFN, Trieste Imperial College, London SW7 2BZ Boston Consulting Group, Munchen Siemens Medizintechnik, Erlangen Deutsche Bank AG, Eschborn Infineon Technologies AG, München University of Karlsruhe, Karlsruhe Instituto de Fisica da Universidade Estadual de Campinas UNICAMP, SP Universität Freiburg, Freiburg Physik-Department Technische Universität München, Garching Lucent Technologies, Naperville, IL Instituto de Física Teórica da Universidade Estadual Paulista, São Paulo Max-Planck-Institut fur Physik, Munchen SPSS Inc., Chicago, IL University of Alabama at Birmingham, Birmingham, AL 35294, London DOE, Germantown, MD Instituto de Física Teórica da Universidade Estadual Paulista, São Paulo

We report new precision measurements of the lifetimes of the {Lambda}{sup +}{sub c} and D{sup 0} from SELEX, the charm hadroproduction experiment at Fermilab. Based upon 1630 {Lambda}{sup +}{sub c} and 10210 D{sup 0} decays we observe lifetimes of {tau}[{Lambda}{sup +}{sub c}]=198.1{+-} 7.0{+-}5.6 fs and {tau}[D{sup 0}]=407.9{+-}6.0{+-}4 .3 fs .

Total cross sections for Sigma- and pi- on beryllium, carbon, polyethylene and copper as well as total cross sections for protons on beryllium and carbon have been measured in a broad momentum range around 600GeV/c. These measurements were performed with a transmission technique adapted to the SELEX hyperon-beam experiment at Fermilab. We report on results obtained for hadron-nucleus cross sections and on results for sigma_tot(Sigma- N) and sigma_tot(pi- N), which were deduced from nuclear cross sections.

We report the first observation of the Cabibbo-suppressed charm baryon decay Xi(+)(c)-->pK(-)pi(+). We observe 150+/-22+/-5 events for the signal. The data were accumulated using the SELEX spectrometer during the 1996-1997 fixed target run at Fermilab, chiefly from a 600 GeV/c Sigma(-) beam. The branching fractions of the decay relative to the Cabibbo-favored Xi(+)(c)-->Sigma+K-pi(+) and Xi(+)(c)-->Xi(-)pi(+)pi(+) are measured to be B(Xi(+)(c)-->pK(-)pi(+))/B(Xi(+)(c)-->Sigma+K-pi(+)) = 0.22+/-0. 06+/-0.03 and B(Xi(+)(c)-->pK(-)pi(+))/B(Xi(+)(c)-->Xi(-)pi(+)pi(+)) = 0.20+/-0.04+/-0.02, respectively.

1. Achieving total reductions of 40–80% for steel 01 YuT ensures high mechanical properties (σy=151–176 N/mm2,σB=294–318 N/mm2, δ4=42–47%) and high values of the strain-hardening index (n=0.233–0.251), regardless of the annealing variant (continuous annealing furnace, bell-type furnaces). 2. Increasing the reductions made during the cold reduction of steel 01YuT to values within the range 75–84% increases the number of grains with the {111} orientation and decreases the number of grains with the {110} orientation. Both of these orientation changes improve the stampability of the steel and result in high values for the coefficient of normal plastic anisotropy and the ductility coefficient (Kdc=11.1–19.0;R=1.96–2.08). 3. The annealing of steel 01YuT with small reductions (40.5, 52.4%) results in a deterioration of the texture of the metal and a decrease in the coefficient of normal plastic anisotropy (Kdc=4.3–7.1;R=1.20–1.45).

There has been measured the crystallization temperature of supercooled Bi particles versus their size in the 3–100 nm range in island films on amorphous carbon substrates. Crystallization temperature is found to decrease with particle size decreasing and the supercooling vanishes for particles of 2–3 nm in diameter. The results obtained are analyzed in the frame of the classic theory of crystallization.

High precision measurements of the differential cross sections for $\pi^0$ photoproduction at forward angles for two nuclei, $^{12}$C and $^{208}$Pb, have been performed for incident photon energies of 4.9 - 5.5 GeV to extract the ${\pi^0 \to \gamma\gamma}$ decay width. The experiment was done at Jefferson Lab using the Hall B photon tagger and a high-resolution multichannel calorimeter. The ${\pi^0 \to \gamma\gamma}$ decay width was extracted by fitting the measured cross sections using recently updated theoretical models for the process. The resulting value for the decay width is $\Gamma{(\pi^0 \to \gamma\gamma)} = 7.82 \pm 0.14 ~({\rm stat.}) \pm 0.17 ~({\rm syst.}) ~{\rm eV}$. With the 2.8% total uncertainty, this result is a factor of 2.5 more precise than the current PDG average of this fundamental quantity and it is consistent with current theoretical predictions., Comment: 4 pages, 5 figures

The data on the reactions K^+Xe --> K^0 \gamma X and K^+Xe --> K^+ \gamma X, obtained with the bubble chamber DIANA, have been analyzed for possible radiative decays of the \Theta^+(1540) baryon: \Theta^+ --> K^0 p \gamma and \Theta^+ --> K^+ n \gamma. No signals have been observed, and we derive the upper limits \Gamma(\Theta^+ --> K^0 p \gamma) / \Gamma(\Theta^+ --> K^0 p) < 0.032 and \Gamma(\Theta^+ --> K^+ n \gamma) / \Gamma(\Theta^+ --> K^+ n) < 0.041 which, using our previous measurement of \Gamma(\Theta^+ --> KN) = (0.39+-0.10) MeV, translate to \Gamma(\Theta^+ --> K^0 p \gamma) < 8 keV and \Gamma(\Theta^+ --> K^+ n \gamma) < 11 keV at 90% confidence level. We have also measured the cross sections of K^+ -induced reactions involving emission of a neutral pion: \sigma(K^+n --> K^0 p \pi^0) = (68+-18) \mub and \sigma(K^+N --> K^+ N \pi^0) = (30+-8) \mub for incident K^+ momentum of 640 MeV., Comment: 8 pages

The PrimEx detector has been built for high precision measurement of the neutral pion lifetime via the Primakoff effect. PrimEx physics data have been collected during October 2004 run at Jefferson Lab. Detailed study of systematics performed during this year allowed to estimate systematic error more precise. The extracted preliminary result for the π0 radiative decay has 2.1% statistical and 1.6% systematic error.

Recent advances in the photon tagging facilities together with the novel, high resolution fast calorimetry made possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths, needed for testing the symmetry breaking effects in QCD, from these measurements at small angles is done by the Primakoff method. This method requires theoretical treatment of all processes participating in these reactions at the same percent level. The most updated description of general processes, including the nuclear coherent amplitude, is done in our previous paper. In this work, based on the framework of Glauber multiple scattering theory, we obtain analytical expressions for the incoherent cross section of the photoproduction of pseudoscalar mesons off nuclei accounting for the mesons absorption in nuclei and Pauli suppression at forward production angles. As illustrations of the obtained formulas, we calculate the incoherent cross section for photoproduction from a closed shell nucleus, 16^O, and from an unclosed shell nucleus, 12^C. These calculations allow one to compare different approaches and estimate their impact on the incoherent cross section of the processes under consideration., Comment: 12 pages,2 figures

With the advent of new photon tagging facilities and novel experimental technologies it has become possible to perform photoproduction cross section measurements of pseudoscalar mesons on nuclei with a percent level accuracy. The extraction of the radiative decay widths from these measurements at forward angles is done by the Primakoff method, which requires theoretical treatment of all processes participating in these reactions at the same percent level. In this work we review the theoretical approach to meson photoproduction amplitudes in the electromagnetic and strong fields of nuclei at forward direction. The most updated description of these processes are presented based on the Glauber theory of multiple scattering. In particular, the effects of final state interactions, corrections for light nuclei, and photon shadowing in nuclei are discussed., Comment: 22 pages, 8 figures