International Nuclear Information System (INIS)

The production of three vector bosons in #gamma# #gamma# collisions studying the reactions #gamma# + #gamma# #-># W"+ + W"- + Z"0 and #gamma# + #gamma# #-># W"+ + W"- + #gamma#. 12 refs., 4 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

Three possibilities to observe the Higgs-top interaction at future {gamma}{gamma}-colliders are discussed: (a) associated Higss production via the {gamma}{gamma}{yields}tanti tH reaction, (b) Higgs obliged radiative correction to the {gamma}{gamma}{yields}tanti t channel, (c) Higgs resonance production via {gamma}{gamma}{yields}H{yields}ZZ. The results obtained show windows of the Higss mass where the Yukawa interaction of the Higss with the top quark can be studied at {gamma}{gamma}-colliders. (orig.).

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The collisions of high energy photons produced at an electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the standard model. The luminosity and energy of the colliding photons produced by backscattering laser beams is expected to be comparable to that of the primary e"+e"- collisions. In this overview, we shall focus on tests of electroweak theory in photon-photon annihilation, particularly #gamma##gamma##->#W"+W"-, #gamma##gamma##->#Higgs bosons, and higher-order loop processes, such as #gamma##gamma##->##gamma##gamma#, Z#gamma# and ZZ. Since each photon can be resolved into a W"+W"- pair, high energy photon-photon collisions can also provide a remarkably background-free laboratory for studying WW collisions and annihilation. We also review high energy #gamma##gamma# tests of quantum chromodynamics, ...

Energy Technology Data Exchange (ETDEWEB)

Measurements of {gamma}-ray, {gamma}{gamma}-coincidence and internal conversion electron spectra from the {sup 106}Cd({alpha},n{gamma}){sup 109}Sn reaction were carried out at 15-20 MeV {alpha}-particle bombarding energies with Ge(HP) {gamma}-ray and superconducting magnetic lens plus Si(Li) electron spectrometers. The energies, relative intensities, internal conversion coefficients and coincidence relations of the {sup 109}Sn transitions were determined, and a more complete, consistent level scheme has been deduced. Spin and parity values have been determined from the internal conversion coefficients, the bombarding-energy dependence of the side-feeding intensities of the states and the available {gamma}-ray angular distribution data. The level scheme was interpreted in the framework of the quasi-particle shell model.

Energy Technology Data Exchange (ETDEWEB)

Carbide reactions occurring in a precipitation-hardening gamma/gamma-prime Ni-Cr alloy during prolonged high-temperature aging are investigated experimentally. It is found that the decomposition of primary MC carbides, which is accompanied by the precipitation of M23C6 particles, may lead to void nucleation and growth. The effect of carbide transformations on the residual properties of the material at temperatures above the equicohesion temperature is observed at the late stages of aging only. 6 references.

International Nuclear Information System (INIS)

The Albedo Theory was applied in order to develop an one-group algorithm for coupled neutron-gamma shielding calculations. The configuration analyzed consists of multilayered plane systems, where a incident neutron current generates gamma radiation through neutron-gamma reactions. The results obtained by Albedo Method and ANISN code have shown excellent agreement. (author)

Energy Technology Data Exchange (ETDEWEB)

Detailed level and decay schemes and the experimental reaction and decay data on which they are based are presented for nuclei with mass number A = 242; the experimental data are evaluated. Adopted values for level and ..gamma..-ray energies, ..gamma..-intensities, as well as other nuclear properties are given.

International Nuclear Information System (INIS)

The energy level schemes of tin isotopes produced in the heavy ion reactions are presented. The using of #gamma# spectroscopy technique is also described. 4 refs, 12 figs.

Energy Technology Data Exchange (ETDEWEB)

The energy and intensity of gamma rays as seen in thermal neutron capture are presented. Only those (n,..cap alpha..), E = thermal, reactions for which the residual nucleus mass number is greater than or equal to 45 are included. These correspond to evaluations published in Nuclear Data Sheets. The publication source data are contained in the Evaluated Nuclear Structure Data File (ENSDF). The data presented here do not involve any additional evaluation. Appendix I lists all the residual nuclides for which the data are included here. Appendix II gives a cumulated index to A-chain evaluations including the year of publication. The capture gamma ray data are given in two tables - the Table 1 is the list of all gamma rays seen in (n,..gamma..) reaction given in the order of increasing energy; the Table II lists the gamma rays according to the ...

International Nuclear Information System (INIS)

With the development of an array of highly-segmented germanium detectors, it now becomes possible to perform in-flight #gamma#-ray spectroscopy experiments on intermediate energy beams with unprecedented #gamma#-ray energy resolution. Presented in this report are examples of two techniques in which SeGA, the most highly-segmented operational germanium array for in-flight spectroscopy with fast beams, was used for the detection of #gamma# rays. SeGA used in conjunction with a high-resolution magnetic spectrograph (S800) to detect the reaction residues in coincidence represents a powerful combination for in-beam #gamma#-ray studies.

International Nuclear Information System (INIS)

We conducted (n, #gamma#) and (d, p) reactions leading to "8"7", "8"8", "8"9"Sr in addition to "8"8Sr (d, t) "8"7Sr and 24 keV neutron capture in "8"8Sr. (orig./HSI).

Energy Technology Data Exchange (ETDEWEB)

Measurements of neutron and gamma-ray penetrations in an iron shield were performed up to a 60-cm depth in a tightly coupled source shield configuration with the fast-neutron reactor YAYOI as a source. Rates of neutron reactions and gamma-ray dose rates in the iron shield were obtained using activation foils and thermoluminescent dosimeters. Analyses of the experiments were made by using the DOT-III code with coupled neutron and gamma-ray cross sections from ENDF/B-IV and POPOP4 libraries. To obtain the source condition for the iron shield analyses, the calculated spectrum was adjusted to the measured reaction rates at the reactor shield boundary. The calculated neutron and gamma-ray distributions in the iron shield show fairly good agreement with the experiments. The effect of difference in Bondarenko-type self-shielding factors on the analyses of the iron ...

Energy Technology Data Exchange (ETDEWEB)

We have studied the signals for a heavy Higgs boson in the processes {gamma}{gamma}{yields}WWWW, and {gamma}{gamma}{yields}WWZZ at a photon linear collider. The results are based on the first complete tree-level calculation for these reactions. We show that, with a forward ``spectator`` W tag, and a central ``spectator`` W veto to suppress backgrounds from transverse W, Z production, the invariant mass spectrum of central WW, ZZ pairs is sensitive to Higgs bosons with a mass up to 1 TeV in a 2-TeV linear collider. ((orig.)).

Energy Technology Data Exchange (ETDEWEB)

The phase transformations and properties of a precipitation-hardened Ni-Cr-based alloy are investigated as a function of C, B, Nb, and Cr contents. It is found that the primary role of Nb consists in the formation of an independent phase, delta-Ni3Nb, a part of a gamma/gamma-prime-delta eutectoid (for high C and B concentrations) and in stimulating the gamma-sigma reaction consecutively with the gamma double prime-delta reaction (for low C and B concentrations). In both cases, the long-term strength characteristics of the Nb-alloyed system are relatively low. The substitution of boron for carbon contributes to a reduction in the number of nucleation sites for topologically close-packed phases and to the formation of more stable (with respect to excess compounds) M3B2 and MB2 borides. The high-boron material exhibits better properties and phase stability under mechanical and thermal ...

International Nuclear Information System (INIS)

The #gamma#-ray spectrum emitted after thermal neutron capture in "8"7Sr was studied at the ILL high flux reactor with pair- and intrinsic Ge-spectrometers. 661 transitions were assigned to the reaction "8"7Sr(n,#gamma#)"8"8Sr and 205 of them were placed into a "8"8Sr level scheme of 47 levels. This represents 88% of the observed intensity. The level energies were determined with a precision of better than 22 ppm; the neutron binding energy was determined as 11 112.69 (22) keV. To aid the analysis high resolution particle spectra of the reaction "8"7Sr(d,p)"8"8Sr were measured at 20 MeV deuteron energy with the Munich Q3D spectrometer. 85 states were observed with this reaction. The data helped to establish newly found levels and to differentiate between primary and secondary transitions in the (n,#gamma#) data. The observed level densities and primary ...

Energy Technology Data Exchange (ETDEWEB)

{gamma}-Butyrolactone-based electrolytes have been used as the operating electrolytes for aluminum electrolytic capacitors. The chemical stability of these electrolytes at elevated temperatures has been examined by monitoring the decrease in their electrolytic conductivities. The deteriorated electrolytes were analyzed by gas and liquid chromatography and the conductivity decrease was directly correlated with the loss of acid components. In quaternary ammonium hydrogen maleate/{gamma}-butyrolactone electrolytes, the maleate anion decomposed by decarboxylation resulting in a complex polymer containing polyester and polyacrylate structures. Quaternary ammonium benzoate/{gamma}-butyrolactone electrolytes decomposed by SN2 reactions giving alkyl benzoates and trialkylamines. The deterioration of the carboxylate salt/{gamma}-butyrolactone electrolytes was accelerated by electrolysis. ...

Energy Technology Data Exchange (ETDEWEB)

{gamma}-ray excitation functions have been measured for the interaction of fast neutrons with {sup 48}Ti (neutron energy from 1 MeV to 250 MeV). The Los Alamos National Laboratory spallation neutron source, at the LANSCE/WNR facility, provided a ''white'' neutron beam which is produced by bombarding a natural W target with a pulsed proton beam. The prompt-reaction {gamma} rays were measured with the large-scale Compton-suppressed Ge spectrometer, GEANIE. Neutron energies were determined by the time-of-flight technique. Excitation functions were converted to partial {gamma}-ray cross sections, taking into account the dead-time correction, the target thickness, the detector efficiency, and neutron flux (monitored with an in-line fission chamber). The data analysis is presented here for neutron energies between 1 to 20 MeV. Partial {gamma}-ray cross ...

International Nuclear Information System (INIS)

Evaluated spectroscopic data for all nuclei with mass number A = 216 are presented together with the relevant level schemes from radioactive decay and nuclear reaction studies. The experimental data are evaluated, inconsistencies and discrepancies are noted, and adopted values for level and #gamma#-ray energies, #gamma# intensities, as well as for other nuclear properties are given. The present evaluation supersedes the earlier one on A = 216 by A. Artna-Cohen (1997Ar04), published in Nuclear Data Sheets 80, 157 (1997).

Energy Technology Data Exchange (ETDEWEB)

A comment on the letter by T. Kajino and A. Arima Phys. Rev. Lett. 52, 739 (1984).

International Nuclear Information System (INIS)

A facility for studying photon-neutron reactions under a braking #gamma#-beam with an energy of up to 26 MeV from a betratron includes Saratov-2, SM-4A, and IBM AT-386 microcomputers. Neutron detectors, pulsed braking radiation dosimeters, and the devices to control the betatron energy are described.

Science.gov (United States)

In terms of the reduced potential energy barrier ? = ?uTS/kT, the rate coefficients for chemical reactions are usually expressed as proportional to e-?. The coupling between vibrational modes of the medium to the reaction coordinate leads to a proportionality of the regularized gamma function of Euler Q(a,?) = ?(a,?)/?(a), with a being the number of modes coupled to the reaction coordinate. In this work, the experimental rate coefficients at various temperatures for several chemical reactions were fitted to the theoretical expression in terms of Q(a,?) to determine the extent of its validity and generality. The new expression affords lower deviations from the experimental points in 29 cases out of 38 and it accounts for the curvature in the logarithmic plots of rate coefficients versus inverse temperature. In the absence of tunneling, conventional theories predict the curvature of ...

International Nuclear Information System (INIS)

Radiation modification on liquid retention properties of native cassava starch, gelatinized at 85"0C, by graft copolymerization with acrylonitrile was carried out by mutual irradiation to #gamma#-rays. A thin aluminium foil was used to cover the inner wall of the reaction vessel so that the extent of homo polymer could be reduced to be less than 1.6% with a distilled water retention value of 665 g/g of the dry weight of the saponified grafted product. Confirmations of graft copolymerization and saponification reactions were made by the infrared spectrophotometric technique. The combined effect of radiation parameters in terms of an irradiation time and a dose rate to the same total dose on the extent of grafting reaction expressed in terms of grafting parameters which directly influenced liquid retention values was evaluated in conjunction with statistical analysis.

International Nuclear Information System (INIS)

A large area Bragg curve spectroscopy (BCS) detector and a position sensitive parallel grid avalanche counter have been developed to study heavy ion reactions, such as inelastic excitations and few nucleon transfer reactions near the Coulomb barrier. Reasonably good resolutions have been achieved for energy, atomic number and angle. A theoretical investigation on the mass dependence of the Bragg peak signal from the BCS detector, shows that there is a negligible mass dependence related to the geometry of the detector. The mass number of the heavy ions which cannot be obtained by the above method, has been identified by detecting the corresponding characteristic gamma rays from the product nuclei with two large solid angle gamma ray detectors. (orig.).

International Nuclear Information System (INIS)

An experimental study was performed in order to study the nuclear structure in odd--odd In isotopes. Low lying nuclear energy levels in "1"1"0In and "1"1"2In were determined from de-excitation #gamma#-rays produced with "1"0"7AG(#alpha#,n#gamma#)"1"1"0In, "1"0"8Pd("6Li,4n#gamma#)"1"1"0In, "1"0"9Ag(#alpha#,n#gamma#)"1"1"2In and "1"1"0Pd("6Li,4n#gamma#)"1"1"2In reactions. In addition, the "1"1"4In energy level structure was investigated with the "1"1"0Pd("7Li,3n#gamma#)"1"1"4In reaction. Properties of de-excitation #gamma#-rays were determined from #gamma#--#gamma# coincidence excitation and angular distribution measurements conducted with Ge(Li) and Ge(intr.) #gamma#-ray detectors. A sequence of intraconnected levels in each of "1"1"0 "1"1"2 "1"1"4In were ...

International Nuclear Information System (INIS)

The electromagnetic field due to an air explosion is here studied: neutron and the gamma-rays, generated by neutronic reactions, deposit energy which ionizes atmosphere; recoil electrons are also created by gamma collisions. This data set allows to solve the Maxwell equations which manage the electromagnetic field. The TRIPOLI-2 code studies the coupled neutron-gamma transport in 3D- geometries by the Monte Carlo method. The code has been modified to calculate the photon energy deposited in matter and the recoil electron current created by Compton effect. The method is tested wiht a simple case; then neutron and gamma transport is studied in air kerma, deposited photon energy, electron current are calculated as functions of space and time and the contributions of the different neutronic reactions are separately evaluated. The calculations presented here are only ...

Energy Technology Data Exchange (ETDEWEB)

The reaction {gamma}d{yields}{pi}{sup +}nn is calculated up to order {chi}{sup 5/2} in chiral perturbation theory, where {chi} denotes the ratio of the pion to the nucleon mass. Special emphasis is put on the role of nucleon recoil corrections that are the source of contributions with fractional power in {chi}. Using the known near-threshold production amplitude for {gamma}p{yields}{pi}{sup +}n as the only input, the total cross-section for {gamma}d{yields}{pi}{sup +}nn is described very well. A conservative estimate suggests that the theoretical uncertainty for the transition operator amounts to 3% for the computed amplitude near threshold. (orig.)

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

The proton beam has an advantage of the sharp dose falloff in dose distribution called Bragg peak while conventional radiation therapy modalities such as photons exhibit considerable amount of exit dose. To take advantage of this property it is important to know the exact location of the distal dose falloff. An error can cause overdose to the normal tissue or underdose to the tumor volume. The only way of finding out the dose distribution in-situ in particle therapy is to measure the gammas produced by nuclear reactions with tissue materials. Two kinds of gammas can be used: one is prompt gamma and the other is coincident gamma from the positron-emission isotopes. We chose to detect prompt gammas, and developed a prompt gamma scanning system (PGS). The proton beams of the proton therapy facility at National Cancer Center were used. The ...

International Nuclear Information System (INIS)

The deferred luminescence (isothermal luminescence -ITL- and thermoluminescence - RTL) emitted by Chlorella cells after #gamma# irradiation at 77 K has been investigated. The decay kinetics of ITL as well as the effect of illumination of both ITL and RTL show that trapped electrons take part in the recombination reactions which give rise to both emissions, and that ITL can be attributed to electron tunnelling. Most strains of Chlorella studied present similar RTL glow curves, the only exceptions found being Chlorella vulgaris (green and bleached strains).

Energy Technology Data Exchange (ETDEWEB)

Energy conservation and local energy deposition are investigated in the context of coupled-particle (i.e., neutrons, gamma rays, and charged particles) transport analysis. For charged particles, the concept of group splitting the 1 = 0 transfer matrix to ensure both particle and energy conservation is introduced. Although these procedures are more complex than those found in the usual neutron or coupled-neutron gamma-ray problem, they yield a consistent approach for the calculation of local energy deposition.

International Nuclear Information System (INIS)

The #pi#g_9_/_2 band structure in "1"2"1Cs is obtained. The experiment was performed at the HI-13 MV tandem accelerator of China Institute of Atomic Energy. The excited states of "1"2"1Cs were populated via the reaction "1"1"2Sn("1"2C, p2n). The #gamma#-#gamma# coincidence data were taken with five BGO-AC HpGe detectors at beam energy of 60 Mev. The energy-level schemes of "1"2"1Cs is presented.

Energy Technology Data Exchange (ETDEWEB)

To understand more fully the mechanism of enzyme-catalyzed phospho group transfer, the stereochemical course at phosphorus of four enzymes has been determined. First, using adenosine (..gamma..-(S)-/sup 16/O, /sup 17/O, /sup 18/O)triphosphate as the substrate, the reaction catalyzed by creatine kinase has been found to proceed with overall inversion of configuration at phosphorus. Second, using adenosine (..beta..-(S)-/sup 16/O, /sup 17/O, /sup 18/O)diphosphate as the substrate, the reaction catalyzed by adenylate kinase has been found also to proceed with overall inversion. Third, the reaction catalyzed by phosphoenolpyruvate carboxylase has been studied using ((S/sub p/)-/sup 16/O, /sup 17/O)thiophospoenolpyruvate as the substrate in H/sub 2/ /sup 18/O. Fourth, using adenosine 5'-O-((..gamma..S/sub p/)-..beta gamma..-/sup ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

Ferrite of system, namely Ni_1_-_xZn_xFe_2O_4 with x = (0.0, 0.2, 0.4, 0.6, 0.8, 1.0), have been prepared by solid state reaction to investigate the effect of gamma rays irradiations using Co"6"0 source on the cation distribution, structural and magnetic properties. The unirradiated and irradiated samples were then subjected to characterization techniques such as X-ray diffraction, magnetization and AC susceptibility. The results of these characterizations are found to be different for irradiated from that of the pristine sample. The modifications in respect of irradiated samples are explained in terms of the ion-induced disorder. The important result of #gamma#-irradiation on the cation distribution, structural and magnetic properties is the change of ratio Fe"2"+/Fe"3"+. Possible reasons on the results are proposed.

International Nuclear Information System (INIS)

Using indigenously developed computer program, coupled neutron gamma multi-group libraries have been generated from MA TXS-NJOY files. The MATXS format contains all the details for each reaction. Temperature and dilution factor dependent cross-sections have been generated and used in discrete ordinates method for benchmark studies of fast critical experiments. We have analyzed criticality benchmarks, which includes CSEWG fast critical benchmarks, "2"3"3U and Pu spheres and enriched uranium spheres using 30-group neutron cross-sections. Neutron and gamma spectra for spheres with point neutron source at the center, are also calculated with 42-group coupled neutron gamma cross-sections. (author)

Energy Technology Data Exchange (ETDEWEB)

A spectroscopic study is performed for high spin states of {sup 55}Fe, {sup 55}Co and {sup 57}Ni. To populate the investigated residues with a relevant cross section, the fusion evaporation reactions of {sup 30}Si({sup 28}Si, 2pn){sup 55}Fe, {sup 30}Si({sup 28}Si, 2pn){sup 55}Co and {sup 4}He({sup 54}Fe, n){sup 57}Ni were chosen. To identify the new {gamma} transitions and to build the energy level schemes, {gamma}-{gamma} coincidence techniques together with excitation functions were employed. Angular distributions and {gamma}-{gamma} angular correlations allowed us to assign the spin values of the nuclear states. The previous level scheme of {sup 55}Fe is extended into the region between 6.5-11 MeV of excitation energy, up to spin 27/2, while the yrast decay pathos of {sup 57}Ni and {sup 55}Co are reported here for the first time. Experimental data are fairly well reproduced by Glaudemans' ...

Energy Technology Data Exchange (ETDEWEB)

The excitation function of ({alpha},{ital xn}) reactions on {sup 191}Ir (abundance 37.3%) and on {sup 193}Ir (abundance 62.7%) has been measured for the 17--55 MeV alpha-particle bombarding energy range. The stacked foil activation technique and {gamma}-ray spectroscopy were used to determine the cross sections. The experimental data were compared with calculated values obtained by means of a geometry-dependent hybrid model. The initial exciton number {ital n}{sub 0}=4 with {ital n}=2, {ital p}=2, and {ital h}=0 gives the best agreements with the presently measured results. To calculate the excitation function theoretically a computer code was used. This set of excitation functions provides a data basis for probing the validity of combined equilibrium and preequilibrium reaction models in a considerable energy range.

International Nuclear Information System (INIS)

We studied the solvent extraction behavior of astatine and found the anomalous behavior of this element similar to radioiodine. Astatine was extracted into CS_2 from acidic solution over a wide range of carrier iodine concentration. The distribution ratios of astatine were determined by measuring the #gamma#-ray from 210 At with a NaI(Tl) detector. A drastic change was observed around at 10"-"4 mol/l as in the case of 131 l. This tendency is well explained by the kinematics of the chemical reactions concerned. (author).

Energy Technology Data Exchange (ETDEWEB)

Applying a total energy absorption {gamma}-ray detector composed of 12 bricks (5x5 cm{sup 2}, 7.5 cm thick) of Bi{sub 4}Ge{sub 3}O{sub 12}(BGO) scintillators, the absolute measurement of capture cross sections for Au and Sb has been made in an energy region between 0.01 eV and 10 eV using the linac time-of-flight method. Incident thermal neutron flux was absolutely determined by using the BGO detection system with a Sm sample. To extend the neutron flux measurement from the thermal neutron region to higher neutron energy, the {sup 10}B(n, {alpha} {gamma}) reaction was applied. Absolute capture yield for the relevant capture sample was obtained by the saturated capture yield at a large resonance of the sample. Gold was selected to investigate the application of the BGO detection system to the absolute measurement of the capture cross sections, since the {sup 197}Au(n, {gamma}){sup 198}Au ...

International Nuclear Information System (INIS)

Experimental excitation functions for deuteron-induced reactions up to 20 MeV on high purity natural hafnium were measured with the activation method using a stacked foil irradiation technique. Metallic hafnium foils with thickness of 10 #mu#m were stacked together with 50 #mu#m thick aluminium and 12 #mu#m thick titanium foils. The aluminium foils served as energy absorber while the titanium foils were used to monitor the energy and intensity of the bombarding deuteron beam. From a detailed remeasurement of the complete excitation function of the "n"a"tTi(d,x)"4"8V monitor reaction it was possible to adopt the proper incident energy and beam intensity by comparing the results with the recommended values. High resolution off-line gamma-ray spectrometry was applied to assess the activity of each foil. From the measured activity independent and/or cumulative elemental or isotopic cross section data for production of Ta, Hf ...

Energy Technology Data Exchange (ETDEWEB)

The flux of cosmic ray antiprotons with kinetic energies between /approximately/1 and 15 GeV is /approximately/5 times greater than the flux predicted on the basis of the leaky-box model. This excess is attributed to secondary antineutron production in compact sources. Because the antineutrons are not confined by the magnetic field of the compact source, they leave the interaction site, decay in interstellar space and account for the apparent excess cosmic ray antiproton flux. The escape and decay of neutrons produced in association with the antineutrons is a source of cosmic ray protons. Observations of the angular variation of the intensity and spectral shape of 100 MeV ..gamma..-rays produced by neutron-decay protons in the reaction p + p ..-->.. ..pi../sup 0/ ..-->.. 2..gamma.. could reveal compact-source cosmic ray production sites. COS-B observations of spectral hardening near point sources, and future ...

Energy Technology Data Exchange (ETDEWEB)

Short communication.

International Nuclear Information System (INIS)

The possibility to transform the future linear e"+e"-colliders into the #gamma#e and #gamma##gamma# colliders with approximately the same energies and luminosities was shown earlier. Their properties are compared from the point of view of possible physical investigations on them. 10 refs.; 1 tab.

International Nuclear Information System (INIS)

The emission of #alpha# particles in coincidence with the most deeply inelastic heavy-ion reactions has been studied for "1"8"1Ta + "1"6"5Ho at 1354 MeV laboratory energy and /sup nat/Ag + "8"4Kr at 664 MeV. #alpha# particle energy spectra and angular distributions, in coincidence with a projectile-like fragment, were acquired both in the reaction plane and out of the reaction plane at a fixed in-plane angle. The in-plane data for both systems are employed to show that the bulk of the #alpha# particles in coincidence with the deep-inelastic exit channel can be explained by evaporation from the fully accelerated fragments. Average velocity diagrams, #alpha#-particle energy spectra as a function of angle in several rest frames, and #alpha#-particle angular distributions are presented. The out-of-plane #alpha# particle angular distributions and the #gamma#-ray multiplicities are used to study the transfer ...

International Nuclear Information System (INIS)

When the history of neutrons is considered, three large discoveries are recalled, that is, the discovery of neutrons by Chadwick in 1932, the discovery of the nuclear fission of uranium by Hahn and Strassmann in 1938, and the continuation of chain reaction in nuclear fission by Fermi and others in 1942. In neutron capture reaction, the reaction cross section can become very large. The fields of research, to which neutrons have contributed most as the experimental probe, are neutron activation analysis and neutron diffraction. The development of the prompt gamma ray analyzer at the JRR-3M in Japan Atomic Energy Research Institute is reported. This method eliminates the various defects in ordinary neutron activation analysis. By installing the cold neutron source with hydrogen cooling in the JRR-3M, the new field of research was opened. As the combination of a lead-moderated spectrometer and an electron ...

International Nuclear Information System (INIS)

Cross-sections for "8"4Sr(n, 2n)"8"3Sr, "8"6Sr(n, 2n)"8"5"mSr, "8"6Sr(n, 2n)"8"5Sr, "8"8Sr(n, 2n)"8"7"mSr, "8"4Sr(n, p)"8"4Rb, "8"6Sr(n, p)"8"6Rb, "8"8Sr(n, p)"8"8Rb and "8"8Sr(n, #alpha#)"8"5"mKr reactions have been measured at neutron energies from 13.5 to 14.6 MeV using activation technique and by means of #gamma#-ray spectrometry. The neutron flux was determined using the monitor reaction "9"3Nb(n, 2n)"9"2"mNb and the neutron energies were measured by the method of cross-section ratios for "9Zr(n, 2n)"8"9Zr to "9"3Nb (n, 2n)"9"2"mNb reactions. The results of present work are compared with data published previously.

Energy Technology Data Exchange (ETDEWEB)

A new method of determining the nuclear level density is presented. This method is based on the statistical analysis of the partial width fluctuations appearing in an excitation function of the radiative proton capture. The method was applied in the case of the /sup 88/Sr(p,..gamma..sub(..omega..))/sup 89/Y and /sup 89/Y(p,..gamma..sub(..omega..))/sup 90/Zr reactions. The density of levels with spin I/sup -/ in /sup 90/Zr and the densities of levels with spins 1/2/sup +/ and 3/2/sup +/ in /sup 89/Y at excitation energies from 10.9 to 11.6 MeV and from 9.3 to 10.8 MeV respectively, were determined with an uncertainty of about 35%.

International Nuclear Information System (INIS)

Upon irradiation of aqueous ethylene glycol/water solutions of native chloroperoxidase (CPO) with "6"0Co-gamma rays at 77K one observes the one-electron reduction of the enzyme active site by radiolytically generated thermolyzed electrons. In the present study the first absorption spectrum of a low-spin ferrous form of CPO is reported which has peaks at 438, 532 and 563 nm, similar to those observed previously for cytochrome P-450. All previously described ferrous forms of CPO are high spin. In order to observe the final results of the CPO reaction with electrons, the spectral changes of native enzyme after room temperature-gamma-irradiation have also been investigated. Evidence of changes is also presented probably connected with disruption of the tertiary structure of enzyme, correlated with decrease of enzyme activity.

British Library Electronic Table of Contents (United Kingdom)

Summary CAG trinucleotide repeat length in the nuclear polymerase gamma gene (POLg) has been shown to be associated with men with reduced fertility. The present study investigated the frequency of CAG repeat length genotypes and three exonuclease motifs of the POLg in relation to the frequency of mitochondrial nucleotide substitutions. DNA from semen samples of 93 normozoospermic men and 192 non-normozoospermic men was isolated and the specific regions of the genes were amplified by polymerase chain reactions (PCR) and sequenced to identify mutations. The genotypic frequencies of pooled POLg CAG repeat lengths, =10/!=10 heterozygotes and !=10/!=10 homozygotes, were significantly different between normozoospermic and non-normozoospermic men (p p POLg genotype. Of the 17 men with non-synonym...

Energy Technology Data Exchange (ETDEWEB)

Regularities in the radiation cross-linking of low-density polyethylene under various conditions of ..gamma..-irradiation were studied. It is shown that at the 0.5 GPa pressure and 450 K the gel formation is initiated at doses of about 1 kGy, i.e. at doses 10 times as low as compared to normal conditions. Abnormally high rate of radiation cross-linking at high temperature and high pressure is an evidence of changes in the mechanism of polyethylene, radiation cross-linking, i.e. of the process transition from nonchain to chain conditions. Decrease in the potential barriers of macroradical reactions with macromolecules is the most probable reason of change in the polymer cross-linking nature.

International Nuclear Information System (INIS)

The radiation induced reactions in LDPE in the presence of phenolic type antioxidants have been studied. It was shown that various antioxidants can influence the polyethylene network formation and the radical yield in different ways. The dependence of network structure on absorbed doses was determined by gel analysis, hot-set test and extraction of antioxidants for samples irradiated with accelerated electrons. It was found that the antioxidants eluted from polyethylene in higher percentage influence polymer crosslinking to a smaller degree. The ESR studies of #gamma#-irradiated blends of polyethylene with antioxidant indicate the presence of alkyl and phenoxyl radicals. The role of antioxidant molecules on radiation induced reactions in polyethylene-antioxidant systems is considered. The correlation between the network structure and the type of additive in polyethylene is also discussed. (author).

International Nuclear Information System (INIS)

The radioactive isotopes of lead are reviewed with respect to their choice for in vitro tracer studies. The #gamma#-photon energy and absence of particle emission in the decay of "2"0"3Pb makes it particularly suitable for these applications. Reaction yields of "2"0"3Pb using "2"0"3Tl targets and proton, deuteron, "3He and "4He beams are listed. Using the preferred reaction "2"0"3Tl (d, 2n)"2"0"3Pb with a 15 MeV deuteron beam, yields of about 75 #mu#Ci #mu#Ahr"-"1, after chemical separation, are reported. Details of target design and chemical separation are given. (U.K.).

International Nuclear Information System (INIS)

This paper describes a reactor design to facilitate a room-temperature nuclear fusion/fission reaction to generate heat without generating unwanted neutrons, gamma rays, tritium, or other radioactive products. The room-temperature fusion/fission reaction involves the sequential triggering of billions of single-molecule, "6LiD 'fusion energy pellets' distributed in lattices of a palladium ion accumulator that also acts as a catalyst to produce the molecules of "6LiD from a solution comprising D_2O, "6LiOD with D_2 gas bubbling through it. The D_2 gas is the source of the negative deuterium ions in the "6LiD molecules. The next step is to trigger a first nuclear fusion/fission reaction of some of the "6LiD molecules, according to the well-known nuclear reaction: "6Li + D #-># 2"4He + 22.4 MeV. The highly energetic alpha particles ("4He nuclei) generated by this nuclear ...

International Nuclear Information System (INIS)

There is an urgent need to improve the reliability of screening cargo containers for illicit nuclear material that may be hidden there for terrorist purposes. A screening system is described for detection of fissionable material hidden in maritime cargo containers. The system makes use of a low intensity neutron beam for producing fission; and the detection of the abundant high-energy #gamma# rays emitted in the #beta#-decay of short-lived fission products and #beta#-delayed neutrons. The abundance of the delayed #gamma# rays is almost an order of magnitude larger than that of the delayed neutrons normally used to detect fission and they are emitted on about the same time scale as the delayed neutrons, i.e., #approx#1 min. The energy and temporal distributions of the delayed #gamma# rays provide a unique signature of fission. Because of their high energy, these delayed #gamma# rays penetrate loW--Z ...

Energy Technology Data Exchange (ETDEWEB)

The isomer /sup 242m/Am with a half-life of 141 yr. is obtained from a (n,..gamma..) capture reaction with /sup 241/Am. The latter is a decay product of /sup 241/Pu. The isomer /sup 242m/Am has the highest known thermal fission cross section. The cross sections of this isomer are evaluated. Unit cell calculations show that nuclear systems with /sup 242m/Am require less fuel by a factor of 2 to 100 compared to conventional fuels. These results indicate that potential applications of americium fuel exist, particularly for space reactors.

International Nuclear Information System (INIS)

The effect of variations of the fundamental constants on the thermonuclear rate of the triple alpha reaction, "4He(#alpha##alpha#, #gamma#)"1"2C, that bridges the gap between "4He and "1"2C is investigated. We have followed the evolution of 15 and 60 M#centre dot# zero metallicity stellar models, up to the end of core helium burning. They are assumed to be representative of the first (Population III) stars. The calculated oxygen carbon abundances resulting from helium burning can then be used to constrain the variation of the fundamental constants.

Energy Technology Data Exchange (ETDEWEB)

The excitation function of the {sup 64}Ni({alpha},p){sup 67}Cu reaction was measured from threshold up to 24 MeV in order to investigate the possibility of production of the {beta}{sup -}-emitting therapeutic radioisotope {sup 67}Cu (T{sub 1/2}=61.9 h). Two stacks of thin metallic self-supporting foils of {sup 64}Ni (enrichment 77.8%) prepared by electrolytic deposition were irradiated by {alpha}-particle beams. The radioactivity was determined via HPGe detector {gamma}-ray spectrometry. Some {sup 67}Ga activity (which emits the same {gamma}-rays as {sup 67}Cu), formed via the {sup nat}Cu({alpha},x){sup 67}Ga process on trace copper impurity in the Ni foils, was also observed. Corrections were done for {sup 67}Ga activity contribution and for the {sup 67}Cu activity escape fraction from the thin Ni-foil. The maximum cross section of the {sup 64}Ni({alpha},p){sup 67}Cu reaction amounts to 34 mb at 22 ...

International Nuclear Information System (INIS)

In order to optimize the production of "2"0"1Tl and "6"7Ga using the (p, xn) reactions on enriched "2"0"3Tl and "6"8Zn targets we established a new set of cross section curves for the most relevant reactions. Target stacks made of up to 15 thin (50 #mu#m) natural Tl or Zn foils interleaved with brass degradation foils were irradiated with incident proton energies from 42 to 10 MeV in overlapping experiments. Yields for "2"0"0","2"0"1","2"0"2"m","2"0"3","2"0"4"mPB and "6"6","6"7","6"8Ga were computed from measured #gamma# emission rates. Where possible, cross section curves for the nuclear reactions involved were computed. Thick target yields and contamination ratios for enriched targets were derived and show good agreement with results from actual production runs. (orig.).

Energy Technology Data Exchange (ETDEWEB)

There is an increasing interest in using radioisotopes of rare earth elements for internal radiotherapy and for imaging in nuclear medicine. {sup 177}Lu is one of the promising radionuclides. This article reports on the first measurements of the excitation function for the production of {sup 177}Lu with proton-beam energies up to 17 MeV on natural hafnium targets. The experimental cross sections for the reaction {sup nat}Hf(p,x){sup 177}Lu were obtained by the activation of a stacked-foil target and subsequent gamma spectrometry. Theoretical cross sections were calculated up to 35 MeV with the EMPIRE nuclear reaction model code. The measured and calculated cross sections were used for deriving the thick-target yields and for estimating the production of other nuclides than {sup 177}Lu. Measured production cross sections of {sup 175,176,177,178}Ta on the same target are also presented.

Science.gov (United States)

Cross sections for (n,2n) (n,p) (n,{alpha}), and (n,d*){sup 1} reactions have been measured on ruthenium isotopes at the neutron energies of 13.5 to 14.8 MeV using the activation technique in combination with high-resolution gamma-ray spectroscopy. Data are reported for the following reactions: {sup 104}Ru(n,2n){sup 103}Ru, {sup 98}Ru(n,2n){sup 97}Ru, {sup 96}Ru(n,2n){sup 95}Ru, {sup 96}Ru(n,p){sup 96}Tc{sup g}, {sup 96}Ru(n,p){sup 96}Tc{sup m}, {sup 104}Ru(n,p){sup 104}Tc, {sup 102}Ru(n,p){sup 102}Tc{sup m}, {sup 104}Ru(n,{alpha}){sup 101}Mo, {sup 102}Ru(n,{alpha}){sup 99}Mo, {sup 96}Ru(n,{alpha}){sup 93}Mo{sup m}, and {sup 96}Ru(n,d*){sup 95}Tc{sup m}. Results were discussed and compared with the previous works.

International Nuclear Information System (INIS)

It is proposed to measure the spot sizes and polarization of #gamma# beams of future #gamma#e and #gamma##gamma# colliders detecting e"+e"- pairs produced as a result of interaction of high energy #gamma# quanta with density modulated and not modulated laser photons. The quantum electrodynamics cross sections, necessary numerical results as well as a short comparison of the proposed method with some other methods are given. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This work concerns the development of nuclear energy and nuclear waste management in particular. Two parts of this study can be distinguished. In the first part (theoretical), a thorium-plutonium fuel based on MOX and dedicated for PWR was investigated in order to transmute plutonium in a potentially low waste fuel cycle. It was shown that this type of fuel is not regenerative but could be used for a transition to the industrial thorium fuel cycle without building new reactors. Thanks to moderated neutron spectra and high loaded actinide mass in the core, U-233 is quickly created ({approx}300 kg/y) for a loss of about {approx}1200 kg of fissile plutonium. In the second part (experimental), we have developed and built a new reaction chamber to measure neutron cross sections of actinides by alpha-gamma spectroscopy. This experimental device (in principle transportable) was commissioned in the high flux reactor of ILL Grenoble. Neutron flux was ...

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We summarize the predictions of different models for total #gamma##gamma# cross-sections. The experimentally observed rise of #sigma#_#gamma#_#gamma# with s radical _#gamma#_#gamma#, faster than that for #sigma#_p_-_b_a_r_p, #sigma#_#gamma#_p is in agreement with the predictions of the Eikonalized Minijet Models as opposed to those of the Regge-Pomeron models. We then show that a measurement of #sigma#_#gamma#_#gamma# with an accuracy of < or approx. 8-9% (6-7%) is necessary to distinguish among different Regge-Pomeron type models (the different parameterisations of the EMM models) and a precision of < or approx. 20% is required to distinguish the predictions of the EMMs and of those models which treat 'photon like a proton', for the energy range 300< s radical_#gamma#_#gamma# <500 GeV. We further show that the difference in model predictions for ...

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... coincidence spectrometry decay excited states gamma spectra half-life

Energy Technology Data Exchange (ETDEWEB)

Large-scale field tracer experiments have been conducted on Ulchin, Wolsung and Daeduk sites for the purpose of validating FADAS and of analyzing the environmental characteristics around the nuclear sites. The most influential factor in atmospheric dispersion is the meteorological condition. During the experiment, meteorological data were measured on the release point and the selected positions among sampling points. Once radioactive materials are released to the atmosphere, members of public may be exposed through the environmental media such as air, soil and foods. Therefore, to protect the public, adequate countermeasures should be taken at due time for those exposure pathways. both processes, of justification and optimization are applied to a countermeasure simultaneously for decision-making. The work scope of Biological research for the radiation protection had contained the search of biological microanalytic methods for assessing the health effect by ...

Science.gov (United States)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at /sup 88/Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in /sup 87/Sr and /sup 89/Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic.) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,..gamma..) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to /sup 88/Sr(d,t)/sup ...

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The Gamma Physics (GaP) program of physical phenomena investigation is proposed on #gamma#p, #gamma#e and #gamma##gamma# colliders at TeV energies. The program contains specialized software (CompHEP system) created for automation of particle interaction processes calculations in the framework of various gauge models. Preliminary physical results are presented (heavy quark production, W, Z production, supersymmetry etc.), and further software development is suggested. (R.P.) 22 refs., 8 figs., 4 tabs.

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Intact rat fat cell exposed to 12.5 ..mu..M (..gamma..-32P)ATP incorporate label into specific proteins within minutes. By solubilizing the reaction mixture with SDS which bypasses the subcellular fractionation steps, the labeled proteins can be identified in autoradiographs of SDS-PAGE gels. The most prominently labeled protein has an M/sub r/ of 42,000. Localization of this component to the cell surface can be made on the basis of inhibition of phosphorylation by addition of a protein derived from the rat brain with protein kinase inhibitory property, susceptibility of the phosphorylated protein to the tryptic digestion, inhibition of phosphorylation of this protein after brief exposure to melittin. To rule out the possibility that the cell surface protein might be a mitochondrial contaminant from broken cells, /sup 32/Pi-labeled and (..gamma..-/sup 32/P)ATP-labeled cells were chromatographed on a rabbit anti-pyruvate ...

Energy Technology Data Exchange (ETDEWEB)

The primary E1, M1 and E2 ..gamma..-radiation in /sup 87,88,89/Sr observed after thermal neutron capture was compared with the predictions of single particle and giant resonance models. The nuclei feature a wide range of neutron binding energies between 6.3 and 11.1 MeV, which makes a 5.5 MeV spectrum of primary transition energies available for investigation. The (n, ..gamma..) reaction was used to estimate the parameters of the spin-flip M1 giant resonance in strontium. The total energy weighted M1 strength of this resonance exceeds the results of shell model and random phase approximation calculations for /sup 90/Zr by a factor of 3-4. The E1 strengths were found to agree with the established giant dipole resonance model. The few data on primary E2 transitions do not allow to differentiate between the giant quadrupole resonance and the single particle models.

Energy Technology Data Exchange (ETDEWEB)

The use of radiochemical detectors in the A approx. = 90 mass region to measure 14 MeV neutron fluences is investigated from the standpoint of cross section sensitivities. Specifically, /sup 90/Zr and /sup 89/Y neutron-induced cascades leading to the production of /sup 89/Zr, /sup 88/Zr, /sup 88/Y, and /sup 87/Y are studied in a one-energy-group approximation, and the sensitivities of the measured ratios R/sub Z/ = /sup 88/Zr//sup 89/Zr and R/sub Y/ = /sup 87/Y//sup 88/Y to the input cross sections are delineated. The most sensitive cross section in each cascade is the cross section that dominates the production of the final isotope in the chain. Only one of the isomeric levels in /sup 90/Zr contributes importantly to the Zr cascade. Burnback (n,..gamma..) and burnup (n,p) reactions are also considered. The (n,..gamma..) effects are small, but (n,p) effects can be substantial due to low energy enhancements of (n,p) cross ...

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This work concerns the study of the nuclear superdeformation phenomenon in the rare earth region (A {approx} 150). The superdeformed (SD) states in Gadolinium and Dysprosium isotopes were produced via heavy-ion induced reactions and studied with the (EUROGAM EUROpean GAmma-ray Microscope) gamma multidetector array. Precise level attenuation method (DSAM). From the derived quadrupole moments, we find large differences in deformation between the yrast bands in neighbour nuclei explained in terms of the case of nuclei corresponding to an axis ratio of 2:1, the shell gaps are not fixed at a specific particle number and deformation. Furthermore the present results indicate that the deformations associated with identical bands are different supporting the picture that mass and deformation changes tend to compensate in SB bands with the same moments of inertia. (author). 114 refs.

International Nuclear Information System (INIS)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a "2"3"8U target with a beam of "7"0Zn at an energy of E_l_a_b=460 MeV. Prompt #gamma# rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

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An accurate neutronics calculation of a local thermal environment within a fast reactor presents a major challenge. A method was previously described that used Monte Carlo techniques within a macrocell to make accurate and reasonably efficient design calculations for such an environment. This method is now being further optimized for the calculation of "2"3"8Pu production in the Fast Flux Test Facility (FFTF). Here, it is not only important to determine the "2"3"8Pu production from neutron capture in "2"3"7Np, but also to calculate the production of the contamination isotope "2"3"6Pu from high-energy (n,2n) and (#gamma#,n) reactions. The power of the Monte Carlo method to automatically include geometry and energy self-shielding is retained by optimization using fission neutron source biasing in both space and energy.

Science.gov (United States)

It is shown that level-density expressions cannot adequately represent or substitute for level structure information when making calculations of the Hauser-Feshbach type for cross sections or isomer-ratios for nuclei in the first few MeV above their ground state. It is stated that such discrete level information should include both experimentally confirmed and theoretically predicted levels. The utility of discrete level information to optimize level density calculations, to compute isomer ratios, in deriving dipole strength functions, and in the analysis of primary gamma ray spectra is emphasized, especially for nuclei far from the line of stability. 29 refs., 12 figs., 6 tabs. (DWL)

International Nuclear Information System (INIS)

Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by #gamma#-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H_5_0 according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from "4"0K contained in the samples. (author).

International Nuclear Information System (INIS)

As a contribution to the US/Japan cooperative program in fusion neutronics, we have prepared a library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and their correlations). This 74-group library, called COVFILS-2, is being used at Los Alamos and at the University of California at Los Angeles in the sensitivity and uncertainty analysis of the Li_2O integral experiment recently performed at the Fast Neutron Source (FNS) in Japan. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are H, "6Li, "7Li, Be, C, N, O, Na, Al, Si, Cr, Fe, Ni, and Pb.

Energy Technology Data Exchange (ETDEWEB)

A gas core fission reactor that utilizes americium in place of uranium is examined for potential utilization as a nuclear rocket for space propulsion. The isomer [sup 242m]Am with a half life of 141 years is obtained from an (n, [gamma]) capture reaction with [sup 241]Am, and has the highest known thermal fission cross section. We consider a 7500 MW reactor, whose propulsion characteristics with [sup 235]U have already been established, and re-examine it using americium. We find that the same performance can be achieved at a comparable fuel density, and a radial size reduction (of both core and moderator/reflector) of about 70%.

Energy Technology Data Exchange (ETDEWEB)

In the framework of nuclear waste transmutation studies, the Mini-INCA project has been initiated at CEA/DSM with objectives to determine optimal conditions for transmutation and incineration of minor actinides (MA) in high intensity neutron fluxes. Our experimental tools based on alpha- and gamma-spectroscopy of the samples and the development of micro fission chambers could gather either microscopic information on nuclear reactions (total or partial cross sections for neutron capture and/or fission reactions) or macroscopic information on transmutation and incineration potentials. Neutron capture cross sections of selected actinides ({sup 241}Am, {sup 242}Am, {sup 242}Pu, {sup 237}Np) have already been measured at ILL, showing some discrepancies when compared to evaluated data libraries but in overall good agreement with recent data. The studies and possibilities offer by the MEGAPIE project to assess neutronic ...

Energy Technology Data Exchange (ETDEWEB)

The properties of the triplet of low-lying states in {sup 101}Mo have been studied through spectroscopy of the {gamma} radation following thermal neutron capture in {sup 100}Mo and {beta}-decay of {sup 101}Nb and through a measurement of the proton angular distributions in the {sup 100}Mo(d, p) reaction with 14 MeV deuteron energy. The half-lives of the 13.5 keV state and the 57.0 keV 5/2{sup +} state have been measured as 226(7) and 133(7) ns, respectively. These values and the quadrupole/dipole mixing ratios of the 13.5 keV and 43.5 keV transitions yield spin and parity 3/2{sup +} for the 13.5 keV level. The E2 components in the 13.5 (3/2{sup +}->1/2{sup +}) and 43.5 keV (5/2{sup +}->3/2{sup +}) transitions are {le} 8x10{sup -4} and 54(9)%, respectively. The possibility of an additional state near to the 57.0 keV level is discussed. IBFM/PTQM calculations, taking into consideration the transitional character of the {sup 100}Mo boson ...

International Nuclear Information System (INIS)

The manufacture and use of wood/plastic composite (WPC) as an example of wood matrix and wood sawdust/plastic composites (SDP) as an example of plastic matrix are reviewed. The raw material for WPC are mostly vinyl monomers, particularly methyl methacrylate and styrene. The reaction in WPC polymerization is radical polymerization. Researches on the radiation sources mostly resulted in gamma-ray. Electron beam can be applied only to thin products. The future use of WPC may be for furnitures, sporting goods, decorative parts and the like. Vital study on the reduction of manufacturing costs is required, for example, the improvement of reaction and the adoption of continuous process must be considered. The raw materials for SDP are wood sawdust, vinyl monomer (mostly methyl methacrylate) and resins. Electron beam accelerators are the most preferable radiation source because of its high efficiency and safe operation. SDP shows ...

Science.gov (United States)

Pd-Ag bimetallic catalysts, supported on gamma-Al2O3, have been evaluated as exhaust catalysts for methanol-fueled vehicles. Laboratory studies have shown that a 0.01% Pd-5% Ag catalyst has greater CO and CH3OH oxidation activity than either 0.01% Pd or 5% Ag catalysts alone. Moreover, Pd and Ag interact synergistically in the bimetallic catalyst to produce greater CO and CH3OH oxidation rates and lower yields of methanol partial oxidation products than expected from a mixture of the single-component catalysts. The Pd-Ag synergism results from Pd promoting the rate of O2 adsorption and reaction with CO and CH3OH on Ag. Rate enhancement by the bimetallic catalyst is greatest at short reactor residence times where the oxygen adsorption rate limits the overall reaction rate.

International Nuclear Information System (INIS)

The cross sections of neutral tensor mesons T=a_2, f, f', ... production in the exclusive #gamma##gamma##->#TT' or semiexclusive #gamma##gamma##->#TX processes (three gluon exchange) in the semihard region s>>vertical stroketvertical stroke>1 GeV"2 are calculated. The relation of investigated processes to the problem of perturbative Odderon is discussed. The possibility of measurements at LEP and at a future #gamma##gamma#-colliders is discussed too. (orig.).

International Nuclear Information System (INIS)

We study the signals for composite vector leptoquarks in e"+e- colliders (CERN e"+e- collider LEP II, Next Linear Collider, and CERN Linear Collider) through their effects on the production of jet pairs, as well as their single and pair productions. We also analyze their production in #gamma#e and #gamma##gamma# collisions.

Energy Technology Data Exchange (ETDEWEB)

The angular ..gamma gamma..-correlations for nuclei of Sr even-even isotopes with A=82, 84, 86, 88 were measured. Multipole structurs of ..gamma..-transtion series and th coefficients multipole mixing were determined.

Science.gov (United States)

The gamma spectrum and gamma - gamma coincidences of /sup 177/W were measured with a Ge(Li) detector. A level scheme was proposed for /sup 177/Ta. (tr-auth)

Energy Technology Data Exchange (ETDEWEB)

We present methods to measure the beam polarizations and the luminosity of [gamma][gamma] colliders at TeV energy scale. The beam polarizations of a [gamma][gamma] collider can easily be monitored by comparing the numbers of events of the processes [gamma][gamma] [yields] l[sup +]l[sup -] and [gamma][gamma] [yields] W[sup +] W[sup -], where l means e or [mu]. The luminosity of a [gamma][gamma] collider is also measurable by the event rate of W boson pair productions and the light lepton pair productions. (orig.)

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... charge-exchange reactions dwba finite-range interactions helium 3 reactions

Energy Technology Data Exchange (ETDEWEB)

A recently developed neutron diagnostic probe system has the potential to satisfy a significant number of van-mobile and fixed- portal requirements for nondestructive verification of sealed munitions and detection of contraband explosives and drugs. The probe is based on a unique associated-particle sealed-tube neutron generator (APSTNG) that interrogates the object of interest with a low-intensity beam of 14-MeV neutrons generated from the deuterium-tritium reaction and that detects the alpha-particle associated with each neutron. Gamma-ray spectra of resulting neutron inelastic scattering and fission reactions identify nuclides associated with all major chemicals in chemical warfare agents, explosives, and drugs, as well as many pollutants and fissile and fertile special nuclear material. Flight times determined from determined from detection times of the gamma-rays and alpha-particles yield a ...

International Nuclear Information System (INIS)

The National Ignition Facility (NIF) is a proposed Department of Energy facility which will contribute to the resolution of important Defense Program and inertial fusion energy issues for energy production in the future. The NIF will consist of a laser system with 192 independent beamlets transported to a target chamber. The target chamber is a multi-purpose structure that provides the interface between the target and the laser optics. The chamber must be capable of achieving moderate vacuum levels in reasonable times; it must remain dimensionally stable within micron tolerances, provide support for the optics, diagnostics, and target positioner; it must minimize the debris from the x-ray and laser light environments; and it must be capable of supporting external neutron shielding. The chamber must also be fabricated from a low neutron activation material. The fusion reaction in the target gives off neutrons, x-ray and gamma rays. The x-rays ...

Energy Technology Data Exchange (ETDEWEB)

Ni catalysts supported on {gamma}-Al{sub 2}O{sub 3}, CeO{sub 2} and CeO{sub 2}-Al{sub 2}O{sub 3} systems were tested for catalytic CO{sub 2} reforming of methane into synthesis gas. Ni/CeO{sub 2}-Al{sub 2}O{sub 3} catalysts showed much better catalytic performance than either CeO{sub 2}- or {gamma}-Al{sub 2}O{sub 3}-supported Ni catalysts. CeO{sub 2} as a support for Ni catalysts produced a strong metal-support interaction (SMSI), which reduced the catalytic activity and carbon deposition. However, CeO{sub 2} had positive effect on catalytic activity, stability, and carbon suppression when used as a promoter in Ni/{gamma}-Al{sub 2}O{sub 3} catalysts for this reaction. A weight loading of 1-5wt% CeO{sub 2} was found to be the optimum. Ni catalysts with CeO{sub 2} promoters reduced the chemical interaction between nickel and support, resulting in an increase in reducibility and stronger dispersion of ...

International Nuclear Information System (INIS)

A #gamma##gamma# collider would extend and complement the physics capability of a linear collider; e.g. it would be suitable for direct measurement of the partial decay width of a Higgs boson into two gamma quanta. This paper discusses choice of laser parameters, luminosity optimization, electron and laser parameters for a gamma- gamma collider as a second interaction region for the Next Linear Collider, laser path, and the lasers. It is concluded that a gamma- gamma collider is technically feasible; however it will require a significant investment in preparatory R ampersand D.

International Nuclear Information System (INIS)

We investigate the chargino production process #gamma##gamma# #-># (W-tilde)"+(W-tilde)"- at high energy #gamma##gamma# colliders in the framework of the minimal supersymmetric standard model (MSSM). Here the high energy #gamma# beams are obtained by the backward Compton scattering of the laser flush by the electron in the basic linear TeV ee colliders. We consider the polarization of the laser photons as well as the electron beams. Appropriate beam polarization could be effective to enhance the cross section to for us extract the signal from the dominant background #gamma##gamma# #-># W"+W"-. (author).

Energy Technology Data Exchange (ETDEWEB)

Cross sections for some electro- and photoinduced spallation reactions on {sup 27}Al and {sup 51}V are measured in the energy region 130 MeV to 580 MeV with the activation method. Comparisons are made with calculations based on the Dalitz formalism for virtual photon spectra, and Monte Carlo calculations based on a cascade evaporation model, respectively. By use of Bremsstrahlung with end-point energies from threshold to 750 MeV, the yields for photo- production of{pi}{sup -}leading to ground and isomeric states in {sup 197}Hg are measured with the activation method. The activity from the Hg-isotopes were measured after a chemical separation of Hg from the target material. The yields and isomeric ratios are compared with impulse approximation calculations. For the photoproduction of {sup 195m}Hg and {sup 192}Hg from {sup 197}Au, the yields were measured. The experimental mean cross sections are compared with data from other experiments and with cascade evaporation ...

International Nuclear Information System (INIS)

Short communication.

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

Short communication.

International Nuclear Information System (INIS)

German 2003 p. 24 Germany Klemz, G. Moenig, K. Sekaric, J. Stahl,

Energy Technology Data Exchange (ETDEWEB)

The cross sections of neutral tensor mesons T=a{sub 2}, f, f', ... production in the exclusive {gamma}{gamma}{yields}TT' or semiexclusive {gamma}{gamma}{yields}TX processes (three gluon exchange) in the semihard region s>>vertical stroketvertical stroke>1 GeV{sup 2} are calculated. The relation of investigated processes to the problem of perturbative Odderon is discussed. The possibility of measurements at LEP and at a future {gamma}{gamma}-colliders is discussed too. (orig.).

International Nuclear Information System (INIS)

... correlation beta-minus decay coincidence spectrometry experimental data

International Nuclear Information System (INIS)

The results that can be expected by e#gamma# and #gamma##gamma# colliders in future are summarized. e#gamma# and #gamma##gamma# colliders have many fine possibilities, and are the economical selection for utilizing future e"+e"- colliders more effectively. e#gamma# and #gamma##gamma# colliders were proposed by former USSR researchers at the beginning of 1980s, but recently, the prospect of realizing future e"+e"- collision type linear accelerator projects has become high, they have become to be considered seriously as the option of remodeling them. The high energy photon beam of e#gamma# and #gamma##gamma# colliders is obtained by causing Compton reverse scattering, irradiating laser beam to the electron beam of e"+e"- accelerators. The production of #gamma#-beam is explained. As for the physics ...

Energy Technology Data Exchange (ETDEWEB)

In the framework of the equivalence theorem the one-loop helicity amplitudes and cross section for the double Higgs production process {gamma}{gamma}{yields}HH are calculated. It is shown that the cross section is measurable at TeV {gamma}{gamma} colliders and is marginally sensitive to the triple-Higgs variation. (orig.).

Energy Technology Data Exchange (ETDEWEB)

The complementarity of e{sup +}e{sup -} and {gamma}{gamma} colliders to discover and explore new physics beyond the Standard Model (SM) is discussed. After briefly surveying a number of various new physics scenarios, we concentrate in detail on signatures for Large Extra Dimensions via the process {gamma}{gamma}{yields}WW.

Energy Technology Data Exchange (ETDEWEB)

The complementarity of e{sup +}e{sub {minus}} and gamma-gamma colliders to discover and explore new physics beyond the Standard Model (SM) is discussed. After briefly surveying a number of various new physics scenarios the authors concentrate in detail on signatures for Large Extra Dimensions via the process gamma-gamma --> WW.

Energy Technology Data Exchange (ETDEWEB)

The results that can be expected by e{gamma} and {gamma}{gamma} colliders in future are summarized. e{gamma} and {gamma}{gamma} colliders have many fine possibilities, and are the economical selection for utilizing future e{sup +}e{sup -} colliders more effectively. e{gamma} and {gamma}{gamma} colliders were proposed by former USSR researchers at the beginning of 1980s, but recently, the prospect of realizing future e{sup +}e{sup -} collision type linear accelerator projects has become high, they have become to be considered seriously as the option of remodeling them. The high energy photon beam of e{gamma} and {gamma}{gamma} colliders is obtained by causing Compton reverse scattering, irradiating laser beam to the electron beam of e{sup +}e{sup -} accelerators. The production of {gamma}-beam is ...

International Nuclear Information System (INIS)

We investigate the sparticle production processes e#gamma# #-># e tilde(Z tilde)_1 and #gamma##gamma# #-># (f tilde)(f tilde and bar) at high energy e#gamma# and #gamma##gamma# colliders in the framework of the minimal supersymmetric standard model (MSSM). It will be shown that the e#gamma# colliders would be more suitable in searching for the heavy selectrons than ee colliders because of the low mass threshold of the process e#gamma# #-># (e tilde)(Z tilde)_1. We show that the standard background processes e#gamma# #-># #nu#W and eZ can be suppressed in terms of initial beam polarization as well as the kinematical cuts on the energy and angle of the final electron. Moreover, it will be argued that the experimental measurements of the cross sections for the processes e#gamma# #-># (e tilde)(Z tilde)_1 and ...

Energy Technology Data Exchange (ETDEWEB)

A radiochemical charged particle activation procedure for production and separation of carrier free {sup 52,56}Mn, {sup 55,56,58}Co and {sup 56,57}Ni has been developed. The radioisotopes produced on bombardment of an iron foil target with a 40 MeV {alpha}-particle beam through the nuclear reactions, Fe({alpha}, {alpha}pxn){sup 52,56}Mn, Fe({alpha}, pxn){sup 55,56,58}Co and Fe({alpha}, nx){sup 56,57}Ni, have been separated by LLX. The target element and the activation products have been sequentially separated from an HCl medium using diethylether and the liquid anion exchanger, TIOA, as extractants. Extent of separation and purity of the carrier free radiotracers at different stages of their LLX separation have been verified by taking recourse to {gamma}-ray spectrometry. (Author).

International Nuclear Information System (INIS)

The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical conductivity and dielectric strength and impaired optical properties such as reduced transparency and luminescence of windows and fiber optics during irradiation. In preparation for construction and operation of these new facilities, the fusion diagnostics community needs to work with materials scientists to develop a better understanding of radiation effects, and to undertake a testing program aimed at developing workable solutions for this multi-faceted problem. A unique ...

International Nuclear Information System (INIS)

"8"3Rb was produced from rubidium by a (#gamma#,2n)-reaction. The specific activity in the irradiated samples of RbCl was 0.2 to 0.3mCi"8"3Rb/gRb. For the separation of the sup(83m)Kr in the liquid phase the cation exchanger Dowex-50WX12 proved to be a suitable carrier. sup(83m)Kr was eluted by bidistilled water. The yield ranged from 85-95%, at an elution time of 3 minutes. The decontamination factor was > 10"6. The separation of sup(83m)Kr in the gaseous phase was effected by floating a "8"3Rb loaded column with an elution gas. The best results were obtained with a generator containing aluminium oxide as carrier for "8"3Rb. The yield of sup(83m)Kr was 90-100%, the decontamination factor > 10"4, the time needed for the separation 20-60 seconds. All generators proved to be very safe even after long time of use. (orig.).

Science.gov (United States)

We report a new measurement of the exclusive electroproduction reaction {gamma}*p{yields}{pi}{sup 0}p to explore the evolution from soft nonperturbative physics to hard processes via the Q{sup 2} dependence of the magnetic (M{sub 1+}), electric (E{sub 1+}), and scalar (S{sub 1+}) multipoles in the N{yields}{delta} transition. 9000 differential cross section data points cover W from threshold to 1.4 GeV/c{sup 2}, 4{pi} center-of-mass solid angle, and Q{sup 2} from 3 to 6 GeV{sup 2}/c{sup 2}, the highest yet achieved. It is found that the magnetic form factor G{sub M}* decreases with Q{sup 2} more steeply than the proton magnetic form factor, the ratio E{sub 1+}/M{sub 1+} is small and negative, indicating strong helicity nonconservation, and the ratio S{sub 1+}/M{sub 1+} is negative, while its magnitude increases with Q{sup 2}.

Energy Technology Data Exchange (ETDEWEB)

We have carried out theoretical calculations for the production of the long-lived isomers {sup 93m}Nb({1/2}{sup {minus}}, 16y), {sup 121m}Sn(11/2{minus}, 55 yr), {sup 166m}Ho(7-, 1200 yr), {sup 184m}Re(8+, 165 d), {sup 186m}Re(8+, 2{times}10{sup 5} yr), {sup 178m}Hf(16+, 31 yr), {sup 179m}Hf(25/2-, 25 d), {sup 192m}Ir(9+, 241 yr), all of which pose potential radiation activation problems in nuclear fusion reactors. We consider (n, 2n), (n,n{prime}), and (n, {gamma}) production modes and compare our results both with experimental data (where available) and systematic. We also investigate the dependence of the isomeric cross section ratio on incident neutron energy for the isomers under consideration. The statistical Hauser-Feshbach plus preequilibrium code GNASH was used for the calculations. Where discrete state experimental information was lacking, rotational band members above the isomeric state, which can be justified theoretically but have not been ...

Energy Technology Data Exchange (ETDEWEB)

We analyze the potential of the e{sup +}e{sup -} linear colliders, operating in the e{gamma} and {gamma}{gamma} modes, to probe anomalous quartic vector-boson interactions through the multiple production of W's and Z's. We examine all SU(2){sub L}(circle times)U(1){sub Y} chiral operators of order p{sup 4} that lead to new four-gauge-boson interactions but do not alter trilinear vertices. We show that the e{gamma} and {gamma}{gamma} modes are able not only to establish the existence of a strongly interacting symmetry breaking sector but also to probe for anomalous quartic couplings of the order of 10{sup -2} at 90% C.L. Moreover, the information gathered in the e{gamma} mode can be used to reduce the ambiguities of the e{sup +}e{sup -} mode.

Science.gov (United States)

New sets of cross sections for the production of krypton isotopes from targets of Rb, Sr, Y, and Zr were constructed primarily on the bases of experimental excitation functions for Kr production from Y. These cross sections were used to calculate galactic-cosmic-ray and solar-proton production rates for Kr isotopes in the moon. Spallation Kr data obtained from ilmenite separates of rocks 10017 and 10047 are reported. Production rates and isotopic ratios for cosmogenic Kr observed in ten well-documented lunar samples and in ilmenite separates and bulk samples from several lunar rocks with long but unknown irradiation histories were compared with predicted rates and ratios. The agreements were generally quite good. Erosion of rock surfaces affected rates or ratios for only near-surface samples, where solar-proton production is important. There were considerable spreads in predicted-to-observed production rates of /sup 83/Kr, due at least in part to uncertainties in chemical abundances. ...

International Nuclear Information System (INIS)

Page 1. ANALYSIS OF REACTION MIXTURE OF LAURIC ACID WITH MONO-

CERN Document Server

An electroweak singlet scalar can couple to pairs of vector bosons through loop-induced dimension five operators. Compared to a Standard Model Higgs boson, the singlet decay widths in the diphotons and Z gamma channels are generically enhanced, while decays into massive final states like WW and ZZ are kinematically disfavored. The overall event rates into gamma gamma and Z gamma can exceed the Standard Model expectations by orders of magnitude. Such a singlet may appear as a resonant signal in the gamma gamma and Z gamma channels, even with a mass above the WW kinematic threshold.

International Nuclear Information System (INIS)

Corrosion testings of model alloys, corresponding by chemical composition to simple and complex-alloyed #gamma#- and #gamma#'-phases of nickel heat-resistant alloys are conducted in sodium sulfate and chloride melts. It is ascertained that heat resistant nickel alloys containing over 50 % of hardening #gamma#'-phase, are subject to disastrous sulfide corrosion (SC). Resistance against SC alloys containing below 50 % of #gamma#'-phase is determined by the resistance of #gamma#-solid solution. 10 refs., 3 figs., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

Incorporation of /sup 32/P from (gamma-32P)ATP into tyrosine residues of the insulin-like growth factor (IGF)-II receptor was observed in a Triton X-100-insoluble fraction of rat adipocyte plasma membranes. IGF-II receptor phosphorylation proceeded to a stoichiometry of approximately 0.5 mol of phosphate/IGF-II binding site after 10 min of incubation at 4 degrees C. A Km for ATP of 6 microM was calculated for this phosphorylation reaction. Addition of IGF-II caused an approximately 2-fold increase in tyrosine phosphorylation of the IGF-II receptor in this preparation. In contrast, phosphorylation of angiotensin II by the Triton X-100 washed membranes was not stimulated by IGF-II. Incubation of purified receptor immobilized on IGF-II agarose or of receptor-enriched low density microsomal membranes with (gamma-32P)ATP did not result in appreciable incorporation of (/sup 32/P)phosphate into the IGF-II receptor nor into ...

Energy Technology Data Exchange (ETDEWEB)

Gamma-irradiation of isolated rat liver mitochondria with up to 475 Gy leading to hydrated electrons (G = 1.9, corrected for reaction with solutes), 30 Gy leading to carbohydrate radicals, (G = 5.6), 100 Gy leading to superoxide radicals (G = 6.2), and 130 Gy leading to formate radicals (G = 6.2) showed no effects on the rate of oxygen uptake in various respiratory states, the respiratory control ratio, or the adenosine diphosphate to atomic oxygen ratio. Typical values were 0.020-0.100 nmol O/sub 2/ s/sup -1/ mg protein/sup -1/ for State 1 respiration, 0.25-0.33 nmol O/sub 2/ s/sup -1/ mg protein/sup -1/ for State 4 respiration and 0.65-1.10 nmol O/sub 2/ s/sup -1/ mg protein/sup -1/ for State 3 respiration. Typical respiratory control ratios ranged from 2.0-3.5 for succinate and 4.0-6.5 for a 1:1 glutamate: malate substrate mixture. Adenosine diphosphate to atomic oxygen ratios with succinate as substrate varied from 1.6 to 1.9. In situ and ...

Energy Technology Data Exchange (ETDEWEB)

Decay processes of H{sub 2}{sup -} anions in {gamma}-rays-irradiated solid parahydrogen were studied by using ESR spectrometer. The following interesting results were obtained. First, the initial amount of ortho-H{sub 2}{sup -} anions in the {gamma}-irradiated solid parahydrogen was three times as large as those of para-H{sub 2}{sup -} anions. Second, the amount of para-H{sub 2}{sup -} anions decreases faster than that of ortho-H{sub 2}{sup -} anions upon storage of the irradiated samples at 4.2 K. Third, the decay rate of H{sub 2}{sup -} anions is accelerated by the addition of D{sub 2} molecules. Forth, H{sub 2}{sup -} anions at 2.2 K decay faster than at 4.2 K. According to the parity conservation rule in a homonuclear diatomic molecule, the energy of ortho-H{sub 2}{sup -} anions at the ground state is lower than that of para-H{sub 2}{sup -} anions, whereas that of ortho-H{sub 2} molecules is higher than that of para-H{sub 2} molecules at ...

International Nuclear Information System (INIS)

Radioisotopes of Pb(II) have been of some interest in radioimmunotherapy and radioimmunoimaging (RII). However, the absence of a kinetically stable bifunctional chelating agent for Pb(II) has hampered its use for these applications. "2"0"3Pb (T_1_/_2=52.02 h) has application potential in RII, with a #gamma#-emission that is ideal for single photon emission computerized tomography, whereas "2"1"2Pb (T_1_/_2=10 h) is a source of highly cytotoxic #alpha#-particles via its decay to its "2"1"2Bi (T_1_/_2=60 min) daughter. The synthesis of the novel bifunctional chelating agent 2-(4-isothiocyanotobenzyl)-1,4,7,10-tetraaza-1,4,7,10-tetra-(2-carbamoyl methyl)-cyclododecane (4-NCS-Bz-TCMC) is reported herein. The Pb[TCMC]"2"+ complex was less labile to metal ion release than Pb[DOTA]"2"- at pH 3.5 and below in isotopic exchange experiments. In addition to increased stability to Pb"2"+ ion release at low pH, the bifunctional TCMC ligand was found to have many other ...

Energy Technology Data Exchange (ETDEWEB)

We present theoretical calculations for the production of the long-lived isomers: {sup 121m}Sn (11/2-, 55 yr), {sup 166m}Ho(7-, 1200 yr), {sup 184m}Re(8+, 165 d), {sup 186m}Re(8+, 2{times}10{sup 5} yr), {sup 178m}Hf(16+, 31 yr), {sup 179m}Hf(25/2-, 25 d), {sup 192m}Ir(9+, 241 yr), all which pose potential radiation activation problems in nuclear fusion reactors if produced in 14-MeV neutron-induced reactions. We consider mainly (n,2n) production modes, but also (n,n{sup {prime}}) and (n,{gamma}) where necessary, and compare our results both with experimental data (where available) and systematics. We also investigate the dependence of the isomeric cross section ratio on incident neutron energy for the isomers under consideration. The statistical Hauser-Feshbach plus preequilibrium code GNASH was used for the calculations. Where discrete state experimental information was lacking, rotational band members above the isomeric state, which can be ...

International Nuclear Information System (INIS)

We calculate the cross sections for the single production of doubly charged dileptons, both scalar and vector, at e"+e"-, e#gamma#, and #gamma##gamma# colliders at #sq root#s =500 GeV and 1 TeV. The e#gamma# mode is by far the most promising---dileptons whose coupling is as weak as #approx#10"-"4#alpha#_e_m can be observed, for masses virtually up to the kinematic limit. Dileptons of mass up to #sq root#s can also be seen in e"+e"- and #gamma##gamma# colliders, for couplings of order #alpha#_e_m. In all three colliders, most of the cross section comes from events in which the only particles detected are e"-e"- (or #mu#"-#mu#"- or #tau#"-#tau#"-), the decay products of the dilepton, yielding an unmistakable experimental signature.

Energy Technology Data Exchange (ETDEWEB)

We perform an optimal-observable analysis of the final charged-lepton/b-quark momentum distributions in {gamma}{gamma}{yields}t t-bar {yields}lX/bX for various beam polarizations in order to study possible anomalous t t-bar {gamma}, tbW and {gamma}{gamma}H couplings, which could be generated by SU(2) x U(1) gauge-invariant dimension-6 effective operators. We find optimal beam polarizations that will minimize the uncertainty in determination of those non-standard couplings. We also compare e e-bar and {gamma}{gamma} colliders from the viewpoint of the anomalous-top-quark-coupling determination.

Energy Technology Data Exchange (ETDEWEB)

CMSX-4 superalloy laser beam welds were investigated by transmission electron microscopy and atom probe field-ion microscopy (APFIM). The weld microstructure consisted of fine (10- to 50-nm) irregularly shaped {gamma}` precipitates (0.65 to 0.75 volume fraction) within the {gamma} matrix. APFIM compositions of the {gamma} and {gamma}` phases were found to be different from those in the base metal. Concentration profiles across the {gamma} and {gamma}` phases showed extensive variations of Cr, Co and Al concentrations as a function of distance within the {gamma} phase. Calculated lattice misfits near the {gamma}/{gamma}` interface in the welds are positive values compared to the negative values for base metal. (orig.).

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

... alpha reactions angular distribution energy-level transitions iridium 185 iridium

International Nuclear Information System (INIS)

... compilation fission products j codes mixed oxide fuels neutron reactions

CERN Document Server

Using $\\gamma \\gamma J/\\psi, J/\\psi \\ra e^+ e^-$ and $\\mu^+ \\mu^-$ events from a sample of $14.0\\times 10^6$ $\\psip$ decays collected with the BESII detector, the branching fractions for $\\psip\\ra \\pi^0\\J$, $\\eta\\J$, and $\\psi(2S)\\ar\\gamma\\chi_{c1},\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi$ are measured to be $B(\\psip\\ra \\pi^0\\J) = (1.43\\pm0.14\\pm0.13)\\times 10^{-3}$, $B(\\psip\\ra \\eta\\J) = (2.98\\pm0.09\\pm0.23)%$, $B(\\psi(2S)\\ar\\gamma\\chi_{c1}\\ar\\gamma\\gamma\\jpsi) = (2.81\\pm0.05\\pm 0.23)%$, and $B(\\psi(2S)\\ar\\gamma\\chi_{c2}\\ar\\gamma\\gamma\\jpsi) = (1.62\\pm0.04\\pm 0.12)%$.

UK PubMed Central (United Kingdom)

The phagocytic and killing abilities of heifer mammary gland macrophages (M phi) and neutrophils were evaluated after exposure to recombinant bovine interferon-gamma (rBoIFN-gamma) stimulation in vitro....Full Text Available

CERN Document Server

The CKM angle $\\gamma/\\phi_{3}$ had been measured by two B-factories, the PEPII collider for the BaBar experiment and the KEKB collider for the Belle experiments. The present paper reports recent progress in $\\gamma/\\phi_{3}$.

UK PubMed Central (United Kingdom)

In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted by two steps of dehydrochlorination to a chemically unstable intermediate, 1,3,4,6-tetrachloro-1,4-cyclohexadiene...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We present the efficient technique to extract the signal of the intermediate mass Higgs boson from the backgrounds at future {gamma}{gamma} colliders. For a clear Higgs detection, it is important to fit the original electron accelerator energy depending on the Higgs mass, to set the polarization of the photon beams and to apply the efficient b quark tagging method. we demonstrate the extraction of information of Higgs parameters and the new physics from the observable physical quantities. It is clearly shown that a future {gamma}{gamma} collider will have a rich potential for study on the new physics, as well as the Higgs physics. (author).

International Nuclear Information System (INIS)

Compton backscattering of laser photons near the interaction point of an e"+e"- or e"-e"- collider can be used to produce a #gamma#-#gamma# or #gamma#-e"- collider. This paper describes the laser requirements, including pulse duration, intensity, energy, and wavelength, for such a collider. For most of the proposed, next generation, e"+e"- colliders, the laser wavelength should be in the near-infrared, with a pulse duration of 1 ps or less and an energy of similar 1 J per pulse. Current chirped pulse amplification laser systems in solid state lasing materials are well suited to meet these requirements. These systems are described. ((orig.)).

International Nuclear Information System (INIS)

... alpha particles beta particles gamma radiation lead hot cells bricks shielding

International Nuclear Information System (INIS)

The production of pairs of doubly charged vector bileptons is studied at future #gamma##gamma# colliders. The unpolarized cross section for the #gamma##gamma##->#Y"-"-Y"+"+ subprocess is analytically calculated and convoluted to predict the number of events in the complete e"+e"-#->##gamma##gamma##->#Y"-"-Y"+"+ process. The gauge or nongauge character of the vector bilepton Y"#+-#"#+-# is discussed. It is found that, as a consequence of its spectacular signature, as it decays dominantly into two identical charged leptons, and also due to its charge contents, which significantly enhance the cross section, the detection of this class of particles with mass in the sub-TeV region can be at the reach of these colliders. The model-independent nature of our results is stressed.

CERN Document Server

Il package software GESIS per la gestione di sistemi spettrometrici gamma

International Nuclear Information System (INIS)

The possibility of gamma-absorption identification of the analyzed substance is considered. the basic provisions of the proposed method are concentrated on the example of carbohydrates and hydrocarbons. The above method is tested experimentally on polyethylenes and polystyrene

International Nuclear Information System (INIS)

Sentinel node (SN) scintigraphy for cervical and vulvar cancer guides the gynaecological oncologist in finding the metastatic lymph nodes during lymphadenectomy. The role of the surgical gamma probe in the sentinel node concept in gynaecological oncology is to localise (SN) both intra-operatively and transcutaneously. Intra-operative hand-held collimated gamma probes are increasingly used for detection of the sentinel lymph node. A comparative evaluation of handheld gamma probes: Neoprobe 1500, Europrobe, Gamma Finder, Gamma Ray Prospector GRP1 and GPR2 was performed using different detection methods. Laboratory tests were performed in which sensitivity, spatial resolution and angular sensitivity were evaluated. The results for each gamma probe were summarised and discussed. Awareness of a gamma probes capabilities and limitations should be ...

CERN Document Server

Determination of absorbed dose in a patient irradiated by beams of x or gamma rays in radiotherapy procedures

Energy Technology Data Exchange (ETDEWEB)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

An experiment has been performed to investigate the chemical reaction between the liquid phases of the eutectic lithium-lead (Li/sub 17/Pb/sub 83/) and water. The reactants and products were constrained within a closed reaction vessel, allowing the extent of reaction to be determined from the partial pressure of the hydrogen reaction product. The data from the tests showed that the extent of reaction did not depend upon the water temperature. The data also indicated that the extent of reaction passed through a maximum as the initial liquid metal temperature was varied from 350 to 500 C, and a model was developed to explain this behavior. 11 refs., 3 figs.

International Nuclear Information System (INIS)

State-of-the-art approaches for the calculation of gamma heating in LMFBR core, blanket and reflector regions have been evaluated, with particular emphasis on coupled neutron-gamma methods/cross section sets. The major source of calculational error was found to be the apparent failure to impose a mass-energy balance on total gamma energy yield from neutron capture and other interactions in the preparation of representative neutron-gamma cross section sets. The applicability of many simplifying assumptions was demonstrated, including: volume-weighted homogenization, insensitivity to the shape of the gamma-source-spectrum, gamma energy deposition equal to gamma energy source more than 10 cm inside large zones of uniform composition, and the negligible effect of bremsstrahlung. A simple one-group method was developed to permit rapid, accurate ...

Energy Technology Data Exchange (ETDEWEB)

Short communication. 2 figs.

International Nuclear Information System (INIS)

The heavy Higgs bosons H,A of the minimal supersymmetric extension of the Standard Model can be produced as resonances in high-energy #gamma##gamma# colliders. Prospects of the search for these particles in bb-bar and neutralino-pair final states are studied in this report. Heavy Higgs bosons can be found with masses up to about 70-80% of the initial e"+e"- collider energy for moderate values of tan #beta#, i.e. in areas of the parameter space not accessible at other colliders.

Science.gov (United States)

The research sponsored by this grant was conducted in two fields of high-energy astrophysics:

International Nuclear Information System (INIS)

We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states b-barb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state t-bart may be enhanced up to two orders of magnitude.

Energy Technology Data Exchange (ETDEWEB)

We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the one of the top quark, at future Linear Colliders operating in {gamma}{gamma} mode at the TeV energy scale. Final states with one or two H{sup {+-}} bosons are considered, as produced by both tree- and loop-level interactions. (orig.)

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Short communication

Energy Technology Data Exchange (ETDEWEB)

The gamma-ray spectrum following neutron capture on /sup 87/Sr was measured at 3 neutron energies: E/sub n/ = thermal, 2 keV, and 24 keV. Gamma rays were detected in a three-crystal Ge(Li)-NaI-NaI pair spectrometer. Gamma-ray intensities deduced from these spectra by spectral unfolding are presented.

International Nuclear Information System (INIS)

... electron spin resonance gamma radiation lipids lyophilization lysozyme radicals

International Nuclear Information System (INIS)

We have constructed a Monte Carlo generator (the corresponding FORTRAN code can be obtained from the authors upon request) for lowest-order predictions for the processes #gamma##gamma##->#4f and #gamma##gamma##->#4f#gamma# in the standard model and extensions thereof by an effective #gamma##gamma#H coupling as well as anomalous triple and quartic gauge-boson couplings. Polarization is fully supported, and a realistic photon beam spectrum can be taken into account. For the processes #gamma##gamma##->#4f all helicity amplitudes are explicitly given in a compact form. The presented numerical results contain, in particular, a survey of cross sections for representative final states and their comparison to results obtained with the program package Whizard/Madgraph. The impact of a realistic beam spectrum on cross sections and distributions is illustrated. Moreover, the size of ...

CERN Document Server

This note studies the single production of scalar or vector diquarks at the LHeC collider.

International Nuclear Information System (INIS)

In 1998, research began at Idaho National Engineering and Environmental Laboratory to investigate the application of "6Li and "7Li isotopes to the measurement of neutron and gamma radiation. Various size pairs of "6Li and "7Li based detectors were exposed to mixed neutron and gamma radiation. Experiments demonstrated that these detectors could be used to measure low level neutron radiation in the presence of high level gamma radiation. (author)

Energy Technology Data Exchange (ETDEWEB)

The working group reviewed the main difficulties foreseen in doing physics at a gamma-gamma collider. They discussed the requirements for the detector, calculated some of the signal and background rates, compared methods of measuring luminosity, looked at how to get the laser beams in, investigated ways of sweeping aside the electrons and considered ways of disposing of the used beams. No overwhelming obstacles were found but important questions still need to be answered. ((orig.)).

International Nuclear Information System (INIS)

Short communication.

Energy Technology Data Exchange (ETDEWEB)

A multi-group neutron-gamma cross-section library in DTF-IV format is supplemented with electron production matrix to generate a coupled neutron-gamma-electron library. This is realized by estimating the contributions from Compton scattering, pair production and photoelectric effect to the electron production cross-sections. A novel application of this new library, which involves transport of neutrons, gammas and electrons, for estimating the Compton current due to a pulse of radiation in air is discussed.

Science.gov (United States)

... PHYSICS ATOMIC AND MOLECULAR PHYSICS AND SPECTROSCOPY NUCLEAR PHYSICS & ELEMENTARY PARTICLE PHYSICS. ...

Energy Technology Data Exchange (ETDEWEB)

Possible anomalous top-quark couplings induced by SU(2)xU(1) gauge-invariant dimension-6 effective operators were studied in the process of ttbar productions and decays at polarized {gamma}{gamma} colliders. Two CP-violating asymmetries, a linear-polarization asymmetry and a circular-polarization asymmetry, were computed including both non-standard ttbar{gamma} and {gamma}{gamma}H couplings. An optimal-observable analysis for the process {gamma}{gamma}{yields}ttbar{yields}l{sup {+-}} was performed in order to estimate the precision for determination of all relevant non-standard couplings, including the anomalous tbW coupling.

International Nuclear Information System (INIS)

We consider single production of leptoquarks (LQ's) at e"+e- and #gamma##gamma# colliders, for two values of the center-of-mass energy: #sq root#s =500 GeV and 1 TeV. We find that LQ's which couple within the first generation are observable for LQ masses almost up to the kinematic limit, both at e"+e- and #gamma##gamma# colliders, for an LQ coupling strength equal to #alpha#_e_m. The cross sections for single production of second- and third-generation LQ's at e"+e- colliders are too small to be observable. In #gamma##gamma# collisions, on the other hand, second-generation LQ's with masses much larger than #sq root#s /2 can be detected. However, third-generation LQ's can be seen at #gamma##gamma# colliders only for masses at most #approx# #sq root#s /2, making their observation more probable via the pair production mechanism.

International Nuclear Information System (INIS)

We consider the possibility of detecting a heavy Higgs boson (m_H>2m_Z) in proposed #gamma##gamma# colliders through the semileptonic mode #gamma##gamma##->#H#->#ZZ#->#q bar ql"+l-. We show that due to the nonmonochromatic nature of the photon beams produced by the laser-backscattering method, the resultant cross section for Higgs production is much smaller than the on-resonance cross section, and generally decreases with increasing collider energy. Although continuum ZZ production is expected to be negligible, we demonstrate the presence of, and calculate sizable backgrounds from, #gamma##gamma##->#l"+l-Z,q bar qZ, with Z#->#q bar q,l"+l-, respectively, and #gamma##gamma##->#t bar t#->#b bar bl"+l-#nu# bar #nu#. This channel may be used to detect a Higgs boson of mass m_H up to around 350 GeV at a 0.5 TeV e"+e- collider, assuming a nominal yearly luminosity of 10--20 fb"-"1.

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A method of detecting explosives in a vehicle includes providing a first rack on one side of the vehicle, the rack including a neutron generator and a plurality of gamma ray detectors; providing a second rack on another side of the vehicle, the second rack including a neutron generator and a plurality of gamma ray detectors; providing a control system, remote from the first and second racks, coupled to the neutron generators and gamma ray detectors; using the control system, causing the neutron generators to generate neutrons; and performing gamma ray spectroscopy on spectra read by the gamma ray detectors to look for a signature indicative of presence of an explosive. Various apparatus and other methods are also provided.

CERN Document Server

The notion of intuitionistic fuzzy set was introduced by Atanassov as a generalization of the notion of fuzzy set. In this paper we apply this concept of Atanassov to ideals, prime ideals and semiprime ideals of gamma semigroups in order to obtain some characterization theorems. We also introduce the notion of Atanassov's intuitionistic fuzzy ideal extension in a gamma semigroup and investigate some of their important properties. A regular gamma semigroup has been characterized in terms of Atanasov's intutionistic fuzzy ideal. Characterization of prime ideal of a gamma semigroup has also been obtained in terms of Atanassov's intutionistic fuzzy ideal extension.

Energy Technology Data Exchange (ETDEWEB)

In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited ...

International Nuclear Information System (INIS)

... states helium 3 reactions ion sources mev range 10-100 neutron spectrometers

UK PubMed Central (United Kingdom)

The effects of temperatures, durations of treatment, and derivations from spermatophores or spermaries on in vitro acrosome reaction of the spermatozoa in the Chinese mitten crab Eriocheir sinensis...Full Text Available

Science.gov (United States)

We briefly reviewed and summarized the experimental study on {beta}-delayed proton decays published by our group over the last 8 years, namely the experimental observation of {beta}-delayed proton decays of nine new nuclides in the rare-earth region near the proton drip line and five nuclides in the mass 90 region with N{approx}Z by utilizing the p-{gamma} coincidence technique in combination with a He-jet tape transport system. In addition, important technical details of the experiments were provided. The experimental results were compared to the theoretical predictions of some nuclear models, resulting in the following conclusions. (1) The experimental half-lives for {sup 85}Mo, {sup 92}Rh, as well as the predicted 'waiting point' nuclei {sup 89}Ru and {sup 93}Pd were 5-10 times longer than the macroscopic-microscopic model predictions of Moeller et al. [At. Data Nucl. Data Tables 66,131(1997)]. These data considerably influenced the predictions ...

Energy Technology Data Exchange (ETDEWEB)

The symmetrical complexes [{sup 99m}Tc][TcN(R{sub 2}PS{sub 2}){sub 2}] [R = CH{sub 3}, CH{sub 2}CH{sub 3}, CH{sub 2}CH{sub 2}CH{sub 3}, CH{sub 2}(CH{sub 3}){sub 2}], and the unsymmetrical complex [{sup 99m}Tc][TcN(Me{sub 2}PS{sub 2})(Et{sub 2}PS{sub 2})] have been prepared, at tracer level, through a two-step procedure involving the preliminary formation of a prereduced technetium nitrido intermediate followed by substitution reaction onto this species by the appropriate dithiophosphinate ligand [R{sub 2}PS{sub 2}]Na. The chemical identity of the resulting complexes have been established by comparison with the corresponding {sup 99}Tc-analogs prepared, at macroscopic level, by reacting the complex [{sup 99}TcNCl{sub 4}] [n-Bu{sub 4}N] (n-Bu = n-butyl) with an excess of ligand in methanol, and characterized by elemental analyses and spectroscopic techniques. The complexes are neutral and lipophilic, and possess a square pyramidal geometry, with an apical Tc N group ...

International Nuclear Information System (INIS)

Prompt fission neutron energy spectra for "2"3"5U and "2"3"9Pu have been measured for fission neutron energies greater than the energy of the incident neutrons inducing fission. The measurements were undertaken to investigate the shape dependence of the fission neutron spectra upon both the incident neutron energy and the mass of the nucleus undergoing fission. Measurements were made for both nuclides at incident neutron energies of 0.50, 1.50, 2.50 and 3.50 MeV. The data are presented either as relative yields or as ratios of measured spectra to that of "2"3"5U at 0.50 MeV. Incident neutrons were produced by the "7Li(p,n)"7Be reaction using a pulsed, bunched proton beam from the 5.5 MV Van de Graaff accelerator at the University of Massachusetts Lowell Radiation Laboratory. Fission neutrons were detected by a thin liquid scintillator with good time resolution capabilities. Neutron energies were determined by time-of-flight techniques with pulse-shape ...

International Nuclear Information System (INIS)

Tritium is produced in large quantities at heavy water nuclear power reactors via the neutron activation reaction "2H(n,#gamma#)"3H. At Wolsung nuclear power plant which has a CANDU reactor, the tritium concentrations in coolant and in moderator systems are 1.5 Ci/Kg-D_2O and 35 Ci/kg-D_2O, respectively, after 12 years of operation. The airborne tritium concentration in main access area is normally less than 5 MPCa except short-term peaks. The average tritium concentrations in main access controlled areas are normally less than 100 MPCa. Tritium is mainly present in the air of workplace of CANDU reactors as a tritiated water vapour. Airborne tritiated water vapour enters the workers body via inhalation and absorption through skin and can result in a significant dose. The occupational doses from tritium at Wolsung NPP have been maintained below 1 man-Sv per year so far. The tritium contribution to the total plant man-Sv changes between 30 ...

International Nuclear Information System (INIS)

Modern nuclear spectroscopy boosts the study of the nuclear matter towards extreme conditions: large excitation energies, high spins, and new nuclear species with unusual ratio between the numbers of neutrons and protons. One of the 'exotic' nuclear regions, practically not studied until now, is the upper part of the N=Z line, from about N#approx#Z#approx#36 to Sn-100, probably the heaviest bound nucleus with N=Z. These nuclei lie close to the proton-drip line. Due to their special composition, it is expected that their study will reveal some phenomena which are less encountered in the nuclei studied till now. In particular, of outstanding interest is the fact that these are the only nuclei which may provide information on the properties of the neutron-proton pairing forces. In spite of its large interest, this nuclear region is exceedingly difficult to reach with the present techniques. The lecture follows the latest results and efforts in the study of the heaviest nuclei with ...

International Nuclear Information System (INIS)

We briefly reviewed and summarized the experimental study on #beta#-delayed proton decays published by our group over the last 8 years, namely the experimental observation of #beta#-delayed proton decays of nine new nuclides in the rare-earth region near the proton drip line and five nuclides in the mass 90 region with N#approx#Z by utilizing the p-#gamma# coincidence technique in combination with a He-jet tape transport system. In addition, important technical details of the experiments were provided. The experimental results were compared to the theoretical predictions of some nuclear models, resulting in the following conclusions. (1) The experimental half-lives for "8"5Mo, "9"2Rh, as well as the predicted 'waiting point' nuclei "8"9Ru and "9"3Pd were 5-10 times longer than the macroscopic-microscopic model predictions of Moeller et al. [At. Data Nucl. Data Tables 66,131(1997)]. These data considerably influenced the predictions of the mass abundances of the ...

Energy Technology Data Exchange (ETDEWEB)

The O({alpha}) electroweak radiative corrections to {gamma}{gamma}{yields}WW{yields}4f within the electroweak standard model are calculated in double-pole approximation (DPA). Virtual corrections are treated in DPA, leading to a classification into factorizable and non-factorizable contributions, and real-photonic corrections are based on complete lowest-order matrix elements for {gamma}{gamma}{yields}4f+{gamma}. Soft and collinear singularities appearing in the virtual and real corrections are combined alternatively in two different ways, namely by using the dipole subtraction method or by applying phase-space slicing. The radiative corrections are implemented in a Monte Carlo generator called Coffer {gamma}{gamma} - the computer code can be obtained from the authors upon request - which optionally includes anomalous triple and quartic gauge-boson couplings in addition and performs a convolution over ...

Energy Technology Data Exchange (ETDEWEB)

In this report, I surveyed physics potential of the {gamma}{gamma} option of a linear e{sup +}e{sup -} collider with the following questions in mind: What new discovery can be expected at a {gamma}{gamma} collider in addition to what will be learned at its 'parent' e{sup +}e{sup -} linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e{sup -} beams, we find that a {gamma}{gamma} collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e{sup -}e{sup -} system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a {gamma}{gamma} collider. CP property ...

Energy Technology Data Exchange (ETDEWEB)

We present the effects of heavy CP-even (H) and CP-odd (A) Higgs bosons on the production cross section of the process {gamma}{gamma}{yields}tt at the energy around the mass poles of the Higgs bosons. It is found that interference between H and A with small mass gap, as well as the ones between Higgs bosons and continuum, contributes to the cross section, if the photon beams are polarized and if we observe the helicity of the top quarks. It is demonstrated in the framework of the minimal supersymmetric extension of the standard model that the H and A contributions can be sizable at future {gamma}{gamma} colliders for small values of tan {beta}. The methods to measure the CP-parity of the Higgs boson are also presented. The statistical significance of detecting the Higgs signals and measuring the Higgs CP-parity is evaluated. (orig.)

International Nuclear Information System (INIS)

"1"0"1Mo is one of the key nuclides in diagnosing fission burn-up. However, it's difficult to measure its nuclear decay data due to its short half-life. Present study concerns in the measurements of #gamma#-ray emission probabilities, P_#gamma#, of "1"0"1Mo and "1"0"1Tc using the balance of scheme method and the entire process recording. The P_#gamma# of "1"0"1Mo by the entire process recording is about 5% lower than that by using the balance of scheme method. The P_#gamma# of "1"0"1Tc using the two methods agree each other very well. So, it seems the #gamma#-ray emission probabilities as well as measurement method still need study further for "1"0"1Mo. (authors)

Energy Technology Data Exchange (ETDEWEB)

One of the main challenges for a high energy {gamma}{gamma} collider is the high repetition rate required for the laser-electron-beam collisions to convert into high energy gamma beams. State-of-the-art, high power lasers have a much lower repetition rate than that of the electron pulses. It is therefore highly desirable that the same laser pulse can be reused. As an example, for NLC where beams collide at 120 Hz, within each collision cycle there are 90 electron bunches separated by 1.4 ns between successive bunches. We show, by invoking a recently invented laser optical box, that the laser pulses can be reused for the entire train of bunches within each collision cycle. ((orig.)).

Science.gov (United States)

PMID:17236670

Energy Technology Data Exchange (ETDEWEB)

Possible explanations are given for the observed asymmetry of the analyzing power in several (rho,..pi../sup -/) reactions.

Norwegian Open Research Archives (NORA)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.