Fusion, resonances and scattering in 12C+12C reaction
Indian Academy of Sciences (India)
B Sahu; S K Agarwalla; C S Shastry
2003-07-01
The variation of fusion cross-section (fus) with energy in the 12C+12C collision is linked to the underlying resonance phenomenon through the behavior of reaction cross-section (r) of which fus is taken as a part. The calculation of fus is done through an energy-dependent imaginary potential in the optical model potential (OMP). Through dispersion relation, such an imaginary potential gives rise to energy-dependent real potential which is incorporated in the OMP. In our calculation, a form of potential for the nuclear part which has a soft repulsive in-built core is introduced based on similar works done earlier. The calculated results of fus are used to explain the oscillatory structure, astrophysical -factor and the decreasing trend at higher energies of the experimental fus data in the case of 12C+12C system with remarkable success. The potential used for fusion calculation is tested for ﬁtting elastic scattering data at some energies and is found good in forward angles. Further improvement of the ﬁtting of these data is obtained by incorporating a coupling potential in the surface region. About twenty resonances are observed in our calculation in the speciﬁc partial waves and some of them are found close to the experimentally identiﬁed resonances in 12C+12C reaction. Thus, we provide an integrated and comprehensive analysis of fusion, resonance and scattering data in the best studied case of 12C+12C reaction within the framework of optical potential model.
Institute of Scientific and Technical Information of China (English)
YANG Yong-Xu; LI Qing-Run; ZHAO Wei-Qin
2002-01-01
Based on the analyses of the elastic angular distributions,an energy-dependent folding potential for the 12C+12C system is established.This potential has a deep real part,and can reasonably well describe the resonant structure in the 12C+12C elastic scattering in the low-energy region of 10 ～ 70 MeV.
$^{-} - {}^{12}C$ elastic scattering above the resonance using diffraction model
Indian Academy of Sciences (India)
M R Arafah
2008-01-01
Phenomenological analysis of the $^{-}- ^{12}C$ elastic scattering differential cross-section at 400, 486, 500, 584, 663, 672 and 766 MeV is presented. The analysis is made in the diffraction model framework using the recently proposed parametrization of the phase-shift function. Good description of the experimental data is achieved at all energies. Microscopic interpretation of the parameters of the phase-shift function is provided in terms of Helm's model density parameters.
Levels in 13N examined by 12C+p elastic resonance scattering with thick target
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
The elastic resonance scattering of 12C+p has been studied in inverse kinematics via a novel thick target method at GIRAFFE facility of HI-13 tandem accelerator laboratory,Beijing.The recoil protons were measured by a △E-E counter telescope based on a large area double-sided silicon strip detector at laboratory angles around θ0=15°.The excitation function for 12C(p,p)elastic scattering has been obtained over a wide energy range of Ec.m.=0.31-3.45 MeV,which was explained quite well by the R-matrix calculation with known resonance parameters of the first three levels in 13N nucleus.Thus it is demonstrated that the present setup can be directly applied to the study of elastic resonance scattering with secondary radioactive beams.
{sup 12}C+p resonant elastic scattering in the Maya active target
Energy Technology Data Exchange (ETDEWEB)
Sambi, S.; Raabe, R.; Flavigny, F.; Khodery, M. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); Borge, M.J.G. [CERN, PH Department, Geneva (Switzerland); Caamano, M.; Fernandez-Dominguez, B. [Universidade de Santiago de Compostela, Department of Particle Physics, Santiago de Compostela (Spain); Damoy, S.; Grinyer, G.F.; Pancin, J.; Perez-Loureiro, D.; Roger, T. [CEA/DSM - CNRS/IN2P3, Grand Accelerateur National d' Ion Lourds (GANIL), Caen (France); Fynbo, H. [Aarhus University, Department of Physics and Astronomy, Aarhus (Denmark); Gibelin, J. [Universite de Caen, CNRS/IN2P3, LPC Caen, ENSICAEN, Caen Cedex (France); Heinz, A.; Jonson, B.; Nilsson, T.; Thies, R. [Chalmers University of Technology, Department of Physics, Goteborg (Sweden); Orlandi, R. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); Instituto de Estructura de la Materia CSIC, Madrid (Spain); JAEA, ASRC, Tokai-mura (Japan); Randisi, G. [KU Leuven, Instituut voor Kern- en Stralingsfysica, Physics Department, Leuven (Belgium); CEA/DSM - CNRS/IN2P3, Grand Accelerateur National d' Ion Lourds (GANIL), Caen (France); Ribeiro, G.; Tengblad, O. [Instituto de Estructura de la Materia CSIC, Madrid (Spain); Suzuki, D. [Universite Paris-Sud, Institut de Physique Nucleaire, CNRS/IN2P3, Orsay (France); Datta, U. [Saha Institute of Nuclear Physics, Kolkata (India)
2015-03-01
In a proof-of-principle measurement, the Maya active target detector was employed for a {sup 12}C(p, p) resonant elastic scattering experiment in inverse kinematics. The excitation energy region from 0 to 3MeV above the proton breakup threshold in {sup 13}N was investigated in a single measurement. By using the capability of the detector to localize the reaction vertex and record the tracks of the recoiling protons, data covering a large solid angle could be utilized, at the same time keeping an energy resolution comparable with that of direct-kinematics measurements. The excitation spectrum in {sup 13}N was fitted using the R-matrix formalism. The level parameters extracted are in good agreement with previous studies. The active target proved its potential for the study of resonant elastic scattering in inverse kinematics with radioactive beams, when detection efficiency is of primary importance. (orig.)
12C+p resonant elastic scattering in the Maya active target
Sambi, S.; Raabe, R.; Borge, M. J. G.; Caamano, M.; Damoy, S.; Fernández-Domínguez, B.; Flavigny, F.; Fynbo, H.; Gibelin, J.; Grinyer, G. F.; Heinz, A.; Jonson, B.; Khodery, M.; Nilsson, T.; Orlandi, R.; Pancin, J.; Perez-Loureiro, D.; Randisi, G.; Ribeiro, G.; Roger, T.; Suzuki, D.; Tengblad, O.; Thies, R.; Datta, U.
2015-03-01
In a proof-of-principle measurement, the Maya active target detector was employed for a 12C( p, p) resonant elastic scattering experiment in inverse kinematics. The excitation energy region from 0 to 3MeV above the proton breakup threshold in 13N was investigated in a single measurement. By using the capability of the detector to localize the reaction vertex and record the tracks of the recoiling protons, data covering a large solid angle could be utilized, at the same time keeping an energy resolution comparable with that of direct-kinematics measurements. The excitation spectrum in 13N was fitted using the R-matrix formalism. The level parameters extracted are in good agreement with previous studies. The active target proved its potential for the study of resonant elastic scattering in inverse kinematics with radioactive beams, when detection efficiency is of primary importance.
High-spin molecular resonances in 12C + 12C
Uegaki, E.; Abe, Y.
2016-05-01
Resonances observed in the 12C + 12C collisions are studied with a molecular model. At high spins J = 10-18, a stable dinuclear configuration is found to be an equator-equator touching one. Firstly, normal modes have been solved around the equilibrium, with spin J and K-quantum number being specified for rotation of the whole system. Secondly, with respect to large centrifugal energy, Coriolis coupling has been diagonalized among low-lying 11 states of normal-mode excitations, which brings K-mixing. The analyses of decay widths and excitation functions have been done. The molecular ground state exhibits alignments of the orbital angular momentum and the 12C spins, while some of the molecular excited states exhibit disalignments with small widths. Those results are surprisingly in good agreement with the experiments, which will light up a new physical picture of the highspin 12C + 12C resonances.
Microscopic analysis of t+12C scattering
International Nuclear Information System (INIS)
Optical model calculations with double-folded microscopic real central and spin-orbit potentials and an imaginary Woods-Saxon potential have been carried out for previously reported t+12C and 58Ni elastic scattering data. The t+12C calculations are not able to reproduce the changes in the measured analyzing powers as a function of bombarding energy, whereas they do describe the t+58Ni data. This analysis suggests that information about the cluster-core t+12C spin-orbit potential, necessary for cluster structure calculations, cannot be determined without considerably more data. Three-particle-transfer reactions leading to 15N show numerous structures that could appear in the t+12C entrance channel. Excitation functions are needed for both the elastic and 4.43 MeV first excited state in 12C if this scattering is to be understood
12C + 12C resonances by a molecular model
International Nuclear Information System (INIS)
Resonances observed in the 12C + 12C collisions are studied with a molecular model. At high spins J = 12–16, a stable dinuclear configuration is found to be an equator- equator touching one as is obtained in the 28Si + 28Si system. With K-quantum number being specified as rotation-vibration model, normal modes have been solved around the equilibrium, firstly. Furthermore, Coriolis coupling has been investigated by diagonalization among low- lying normal-mode states with K = 0 and K-excitation. It is found that the Coriolis coupling introduces about 30% of K-mixing into the K = 0 molecular ground states of J = 12–16. The analyses of the angular momentum coupling show up a dominance of the lowest L in the inelastic channel of the molecular ground state newly obtained. Thus alignments appear strongly in the inelastic channel, which is in agreement with the explanation by the band crossing model. Discussion is given on ''why disalignments appear in the 28Si + 28Si system, in contrast to the above results''
Angular correlation measurements for {sup 12}C{sup 12}C,{sup 12}C{sup 12}C 3{sup -} scattering
Energy Technology Data Exchange (ETDEWEB)
Wuosmaa, A.H.; Betts, R.R.; Freer, M.
1995-08-01
Previous studies of inelastic {sup 12}C + {sup 12}C scattering to a variety of final states identified significant resonance behavior in a number of different reaction channels. These resonances can be interpreted as either potential scattering resonances, or as population of cluster structures in the compound nucleus {sup 24}Mg, or as some interplay between the two mechanisms. Currently, for many of these resonances the situation remains unclear. One example is a large peak observed in the excitation function for the 3{sup -} - g.s. excitation, identified in previous work performed at the Daresbury Laboratory in England. This peak is observed at the same center-of-mass energy as one observed in the O{sub 2}{sup +}-O{sub 2}{sup +} inelastic scattering channel. That structure was suggested to correspond to exotic deformed configurations in the compound nucleus {sup 24}Mg. As the peak in the 3{sup -} + g.s. exit channel occurs at precisely the same energy as the purported resonance, it is tempting to associate the two. Before such an association can be confirmed or ruled out, further information must be obtained about the 3{sup -} + g.s. structure. In particular, it is important to determine the angular momenta that dominate the 3{sup -} + g.s. structure.
Spin alignment and resonances in the system 12C+12C - a study with a 4π gamma-spectrometer
International Nuclear Information System (INIS)
In order to characterize the resonance behaviour of 12C+12C in the rotational degrees of freedom in the present thesis the alignment of the intrinsic spin(s) in the reactions 12C12C → 12C+12C* (2+, 4.44 MeV) and 12C+12C → 12C*(2+)+12C*(2+) was studied for nine incident energies in the range 19.29 ≤ Ec.m. ≤ 34.65 MeV in dependence on the scattering angle 400 c.m. ≤ 900. From the position-sensitive detection of the particle-particle coincident 4.44-MeV photons by the Darmstadt-Heidelberg crystal-ball spectrometer the scattering amplitudes characterized by the spin-orientation quantum number m for the single-inelastic scattering could be determined nearly completely. Their angular dependence was subjected to a partial wave analysis as its result the angular-momentum distribution is obtained as function of the incident energy and the m quantum number. For the double-inelastic 12C+12C scattering from the 2-photon intensity distribution the probabilities of the correlated alignment of both fragment spins were derived. (orig./HSI)
Is there a giant monopole resonance in 12C
International Nuclear Information System (INIS)
Arguments that the 0+ (Esub(x)=20.3 MeV) state recently found in 12C can be interpreted as a giant resonance are given. The calculations of differential cross sections of the 0+ state excitation in elastic and inelastic scattering of 3He, 4He and 6Li on 12C and compared with experimental data. Using transition densities calculated in the hyperspherical function method it is shown that in the framework of the collective model this single state exhausts the monopole energy weighted sum rules
Energy Technology Data Exchange (ETDEWEB)
Davies, J.A. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Almeida, F.J.D. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Haugen, H.K. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Siegele, R. (Accelerator Lab., McMaster Univ., Hamilton, ON (Canada)); Forster, J.S. (AECL Research, Chalk River Labs., ON (Canada)); Jackman, T.E. (Inst. for Microstructural Sciences, NRC, Ottawa, ON (Canada))
1994-03-01
Extremely strong ([alpha], [alpha]) elastic scattering resonances - more than 100 times the Rutherford value - occur in [sup 16]O at 7.35-7.65 keV and in [sup 12]C at 5.50-5.80 MeV, thus allowing the normal RBS technique to be extended to low-Z components, such as oxygen and carbon. Both resonances have been calibrated over the appropriate 300 keV energy regime with an overall accuracy of [+-]4%. Some recent examples of their use in profiling oxygen and carbon in various substrates are given. (orig.)
Vacuum polarization in sub-coulomb 12C- 12C scattering (II)
Trautmann, D.; Baur, G.; Vetterli, D.; Egelhof, P.; Henneck, R.; Jaskòla, M.; Mühry, H.; Sick, I.
In order to extract the effect of vacuum polarization from 12C- 12C elastic scattering data, a detailed theoretical study of the low-energy Mott cross section is performed. It is shown that the contributions of nuclear interaction, Coulomb excitation, bremsstrahlung can be neglected, while radiative corrections and nuclear polarizability can be described by a small additional potential. Screening by atomic electrons is corrected by a screening function, which acts on all potentials. Relativistic effects are accounted for using the "Todorov equation". In order to overcome numerical difficulties for very long range potentials a WKB approximation and a semiquantal approach are discussed and compared. The study shows that the first-order vacuum-polarization potential contributes most to the correction of the cross section. All other contributions are at least one order of magnitude smaller.
Neutrino neutral-current elastic scattering on 12C
Butkevich, A. V.; Perevalov, D.
2011-01-01
The neutral current elastic scattering of neutrinos on Carbon and $CH_2$ targets is computed using the relativistic distorted-wave impulse approximation with relativistic optical potential. Results for exclusive and inclusive neutrino reactions on ${}^{12}$C target are presented. We show that the nuclear effects on the shape of four-momentum transferred squared distribution $d\\sigma/dQ^2_{QE}$ in neutrino neutral-current and charged-current quasi-elastic scattering are similar. We also calcul...
Dispersion effects in elastic electron scattering from 12C
International Nuclear Information System (INIS)
The results of an experiment, especially designed to investigate to what extent dispersion effects contribute to the reaction mechanism of elastic electron scattering from 12C, are presented and discussed. Particular attention is given to the discussion of corrections to parameters used in the calculation of the cross section. Tables of the resulting cross sections are given for the ground state and for the 2+ and 0+ states at, respectively, 4.439 and 7.655 MeV. The one-photon exchange approximation for elastic electron scattering from 12C is investigated by testing the energy dependence of the form factor in the region of the first diffraction minimum. The energy dependence observed is interpreted in terms of dispersion effects. 109 refs.; 33 figs.; 14 tabs
International Nuclear Information System (INIS)
Full text: The fulfillment of planned works on measurements of differential cross sections of elastic scattering of protons on nuclear 12C at the energy region of 350†1050 keV suggests the preparation of thin self - supporting carbon target. The self - supporting target is necessary in order to perform investigations in the total angular range. In the future last data will be used in order to determine optical potentials and scattering phases for this nuclear in the energy range of astrophysical interest. There was prepared target layer of the 12C with natural composition of carbon and of thickness of 17.4 μg/cm2. The spraying was conducted in the vacuum evaporation installation (VUP - 4) by an electron bombardment method. Carbon was sprayed on a glass plate with previously deposited of layer salt. After a heating during 12 hours at the temperature of 150 oC the film of carbon was floated from glass plate and self - supporting target has been picked up on the specially prepared target frame. In order to determine thickness of target there was used the resonance chamber, installed in the protons channel of the accelerator RAC - 2 - 1 (INP NNC RK), with the help of which there was measured energy loss of the protons beam during the passage through target, disposed in the central chamber. For this purpose there was used the reaction 27Al(p,γ)28Si with narrow resonance with ER = 992 keV and with detection of gamma-quanta with Eγ = 1779 keV. On shift of the resonance ER=992 keV in the reaction 27Al(p,γ)28Si, which takes place owing to protons energy loss in the thickness of carbon film, and using table values of brake quantities S(Ep)[MeV·cm2/g] [1], there was determined thickness of this fine film. Such the method allows to determine thicknesses of films in the interval of (10 † 100) mcg/cm2 with the accuracy of not worse than 5%. In the present work there were carried out measurements of angular distributions of cross sections of the elastic scattering 12C
Elastic α-{sup 12}C scattering at low energies in cluster effective field theory
Energy Technology Data Exchange (ETDEWEB)
Ando, Shung-Ichi [Sunmoon University, School of Mechanical and ICT Convergence Engineering, Asan, Chungnam (Korea, Republic of)
2016-05-15
The elastic α-{sup 12}C scattering at low energies is studied employing an effective field theory in which the α and {sup 12}C states are treated as elementary-like fields. We discuss scales of the theory in the stellar energy region where the {sup 12}C(α, γ){sup 16}O process occurs, and then obtain an expression of the elastic scattering amplitudes in terms of effective-range parameters. Using experimental data of the phase shifts for l=0,1, 2 channels at low energies, for which the resonance regions are avoided, we fix values of the parameters and find that the phase shifts at the low energies are well reproduced by using three effective-range parameters for each channel. Furthermore, we discuss problems and uncertainties of the present approach when the amplitudes are extrapolated to the stellar energy region. (orig.)
An orthogonality condition model treatment of elastic and inelastic (α, 12C) scattering
International Nuclear Information System (INIS)
Elastic and inelastic scattering of α-particles on the deformed nucleus 12C are investigated in the range of incident α-particle energies of 9 to 11 MeV by using the coupled-channel method with orthogonality condition. A doubly folded potential generated by the shell model wave functions of the α-particle and the deformed nucleus 12C is employed for the relative motion between the α-particle and 12C. Good agreement between theory and experiment is obtained for the elastic and inelastic angular distributions and the resonance structures. It is found, from the Born series expansion of the T-matrix, that the orthogonality constraint stresses the effects of the channel-coupling between the elastic and inelastic processes, and it indicates that the DWBA does not work well in this system. (author)
Compound and quasi-compound states in low-energy scattering of nucleons from 12C
Pisent, G; Canton, L; Amos, K; Karataglidis, S; Van der Knijff, D
2005-01-01
A multi-channel algebraic scattering theory has been used to study the properties of nucleon scattering from 12C and of the sub-threshold compound nuclear states, accounting for properties in the compound nuclei to ~10 MeV. All compound and quasi-compound resonances observed in total cross-section data are matched, and on seeking solutions of the method at negative energies, all sub-threshold states in 13C and 13N are predicted with the correct spin-parities and with reasonable values for their energies. A collective-model prescription has been used to define the initiating nucleon-12C interactions and via use of orthogonalizing pseudo-potentials, account is made of the Pauli principle. Information is extracted on the underlying structure of each state in the compound systems by investigating the zero-deformation limit of the results.
Quantum partner-dance in the 12C + 12C system yields sub-Coulomb fusion resonances
International Nuclear Information System (INIS)
A preliminary study of the 12C + 12C sub-Coulomb fusion reaction using the time-dependent wave-packet method is presented. The theoretical sub-Coulomb fusion resonances seem to correspond well with observations. The present method might be a more suitable tool for expanding the cross-section predictions towards lower energies than the commonly used potential-model approximation.
Resonance states in 16O + 16O, 12C + 16O, + 16O and + 12C with modified Morse potentials
Indian Academy of Sciences (India)
B Sahu; L Satpathy
2008-05-01
The resonance states in 16O + 16O, 12C + 16O, + 16O and + 12C are described using modified Morse potential proposed earlier whose success has already been demon-strated in the case of 12C + 12C system. The general validity of such a potential with long range, shallow depth and repulsive soft core determined from the resonance data itself is being examined through the present study of the resonances in the above four systems. In each system, the experimental data of a large number of states have been successfully described with a modified Morse potential. The success points out a common mechanism of the origin of these states, and reaffirms authentically the diatomic-like rotational and vibrational picture of the nuclear molecular resonances proposed previously. The close resemblance between the physics of diatomic molecules and nuclear molecular resonances extending to the level of potential which is Morse type in both the cases - although belong to two different areas of physics - is further strengthened through the present study.
International Nuclear Information System (INIS)
The 12C + 12C reaction is important to understand the nuclear burning in stellar evolution. In this work, we calculate the 12C + 12C microscopic potential based on the effective nucleon-nucleon (NN) interaction and the wave functions of interaction nuclei. The Optical Model analysis for elastic scattering angular distributions of 12C + 12C system at energies near to the Coulomb barrier agrees well with the experimental data, which makes sure the applicability of our obtained potential. The Barrier Penetration Model (BPM) and WKB approximation are applied to estimate the astrophysical S factor, which is reasonable to measurement results. (author)
Spectroscopy of {sup 12}C within the boundary condition for three-body resonant states
Energy Technology Data Exchange (ETDEWEB)
Kurokawa, Chie [Meme Media Laboratory, Hokkaido University, Sapporo 060-8628 (Japan)]. E-mail: chie@nucl.sci.hokudai.ac.jp; Kato, Kiyoshi [Department of Physics, Faculty of Science, Hokkaido University, Sapporo 060-0810 (Japan)
2007-08-01
The 3{alpha}-cluster structure of excited states in {sup 12}C is investigated by taking into account the correct boundary condition for three-body resonant states. In this study, we adopt the Complex Scaling Method (CSM), which enables us to obtain the resonant states that can be described as square integrable states with the same boundary conditions as those of the bound states, and calculate not only resonance energies but also the total decay widths of the 3{alpha} system. We compare the calculated resonance parameters to the experimental data and also to the previous 3{alpha} model results obtained with a bound state approximation. Our results well explain the many observed levels and give an assurance for the presence of the second 2{sup +} state, which is expected by the 3{alpha} model calculations with the approximations of bound state or two-body scattering. As for the negative-parity states, it is considered that the calculated 4{sup -} state is assigned to the observed E{sub x}=13.4MeV state. Through the calculation of channel amplitudes, the obtained third 0{sup +} state is found to have a s-wave dominant and a more dilute structure compared to the second 0{sup +} state.
Refractive effects and Airy structure in inelastic $^{16}$O+$^{12}$C rainbow scattering
Ohkubo, S; Ogloblin, A A; Gloukhov, Yu A; Dem'yanova, A S; Trzaska, W H
2014-01-01
Inelastic $^{16}$O +$^{12}$C rainbow scattering to the $2^+$ (4.44 MeV) state of $^{12}$C was measured at the incident energies, $E_L$ = 170, 181, 200, 260 and 281 MeV. A systematic analysis of the experimental angular distributions was performed using the coupled channels method with an extended double folding potential derived from realistic wave functions for $^{12}$C and $^{16}$O calculated with a microscopic $\\alpha$ cluster model and a finite-range density-dependent nucleon-nucleon force.The coupled channels analysis of the measured inelastic scattering data shows consistently some Airy-like structure in the inelastic scattering cross sections for the first $2^+$ state of $^{12}$C, which is somewhat obscured and still not clearly visible in the measured data. The Airy minimum was identified from the analysis and the systematic energy evolution of the Airy structure was studied. The Airy minimum in inelastic scattering is found to be shifted backward compared with that in elastic scattering.
Further evidence for a dynamically generated secondary bow in $^{13}$C+$^{12}$C rainbow scattering
Ohkubo, S; Ogloblin, A A
2015-01-01
The existence of a secondary bow is confirmed for 13C+12C nuclear rainbow scattering in addition to the 16O+12C system. This is found by studying the experimental angular distribution of 13C+12C scattering at the incident 13C energy $E_L$=250 MeV with an extended double folding (EDF) model that describes all the diagonal and off-diagonal coupling potentials derived from the microscopic wave functions for 12C using a density-dependent nucleon-nucleon force. The Airy minimum at \\theta$ $\\approx$70$^\\circ$, which is not reproduced by a conventional folding potential, is revealed to be a secondary bow generated dynamically by a coupling to the excited state 2+ (4.44 MeV) of 12C. The essential importance of the quadruple {\\it Y2} term (reorientation term) of potential of the excited state 2+ of 12C for the emergence of a secondary bow is found. The mechanism of the secondary bow is intuitively explained by showing how the trajectories are refracted dynamically into the classically forbidden angular region beyond t...
Qu, W. W.; Zhang, G. L.; Terashima, S.; Guo, C. L.; Tanihata, I.; Le, X. Y.; Wang, T. F.; Zhang, X. H.; Sun, Z. Y.; Duan, L. M.; Hu, R. J.; Lu, C. G.; Ma, P.
2016-10-01
To obtain the angular distributions of 12C + 12C elastic scatterings with the incident energies of 200-400A MeV for the study of three-body forces, a detector system was constructed at second Radioactive Ion Beam Line in Lanzhou (RIBLL2) of Institute of Modern Physics (IMP). This system was composed of five plastic scintillation detectors with two read-outs for each detector, a Multi Wire Proportional Chamber (MWPC) and a 4×4 CsI(Tl) array. The 12C beam with the incident energy of 200A MeV on a natural carbon target was used to test this detector system. It is found that the plastic scintillation detector can give the good energy loss (Δ E) and time of flight (TOF) signals, it can also reflect the position information of scattered 12C events. MWPC can precisely provide the trajectories of scattered particles. This system has a very good particle identification ability and can clearly distinguish the scattered 12C particles from the fragments. It can be used for the study of the three-body forces effect for high energy heavy-ion scattering.
Causality principle and nuclear dispersion anomaly in the elastic scattering for α+12C system
Institute of Scientific and Technical Information of China (English)
Abdolmajid Izadpanah
2010-01-01
The optical model analysis of the alpha particle elastic scattering on a carbon target was performed on the basis of the dispersion relation between the real and imaginary parts of the calculated volume integrals. A nuclear dispersion anomaly in an α+12C system was observed and interpreted clearly.
Elastic scattering of 6He from 12C at 38.3 MeV/nucleon
Institute of Scientific and Technical Information of China (English)
DONG Hong-Fei; MA Yin-Qun; MA Zhong-Yu
2009-01-01
The microscopic optical potential of nucleus-nucleus interaction is presented via a folding method with the isospin dependent complex nucleon-nuclear potential, which is first calculated in the framework of the Dirac-Bruecker-Hartree-Fock approach. The elastic scattering data of 6He at 229.8 MeV on 12C target are analyzed within the standard optical model. To take account of the breakup effect of 6He in the reaction an enhancing factor 3 on the imaginary potential is introduced. The calculated 6He+12C elastic scattering differential cross section is in good agreement with the experimental data. Comparisons with results in the double-folded model based on the M3Y nucleon-nucleon effective interaction and the few the body Glauber-model calculations are discussed. Our parameter free model should be of value in the description of nucleus-nucleus scattering, especially unstable nucleus-nucleus systems.
4.2 GeV α-12C Elastic Scattering Based on α-Particle Model
Institute of Scientific and Technical Information of China (English)
YANG Yong-Xu; LU Xiao; LI Qing-Run
2008-01-01
Based on the a-particle model of 12C nucleus, the differential cross sections for α-12 C elastic scattering at incident energy of 4.2 GeV have been calculated within the framework of Glauber multiple scattering theory. The results show that the main features of the measured angular distribution of the cross sections can be reasonably described. The parameterizedα-α scattering amplitude, which is the basic input to construct the α-12C scattering Glauber amplitude in the a-particle model, is obtained by fitting the α-α scattering data.
Elastic scattering and total reaction cross sections for 8Li+12C
International Nuclear Information System (INIS)
Full text: The elastic scattering angular distribution for 8Li on 12C has been measured at ELAB= 23.9 MeV with 8Li radioactive nuclear beam produced by the Radioactive Ion Beams in Brazil facility (RIBRAS). This angular distribution was analysed in terms of optical model with Woods-Saxon and double-folding Sao Paulo potentials. The roles of the breakup and inelastic channels were also investigated with cluster folding and deformed potentials, respectively, through coupled channels calculations. The angular distributions for the proton-transfer 12C(8Li,9Be)11B reaction was also measured at the same energy, simultaneously with the elastic scattering. The spectroscopic factor for the 9Be I 8Li+p> bound system was obtained through DWBA (Distorted-Wave Born Approximation) calculations with the code Fresco, and compared with shell model calculations and other experimental values. The spectroscopic factor obtained was used for normalization of the capture reaction cross section 8Li(p, gamma)9Begs. The depth of the scattered potential obtained was 40,1 +- 1,6 MeV. The astrophysical S-factor curves and the reaction rate for the capture reaction 8Li(p,gamma)9Begs were calculated. Total reaction cross sections for the present system were also extracted from the elastic scattering analysis. A systematic of the reduced reaction cross section obtained from the present and published data on 6;7;8Li isotopes on 12C was performed as a function of energy. (author)
Neutral weak-current two-body contributions in inclusive scattering from {sup 12}C
Energy Technology Data Exchange (ETDEWEB)
Lovato, Alessandro [ANL; Gandolfi, Stefano [LANL; Carlson, Joseph [LANL; Pieper, S. C. [ANL; Schiavilla, Rocco [JLAB, ODU
2014-05-01
An {\\it ab initio} calculation of the sum rules of the neutral weak response functions in $^{12}$C is reported, based on a realistic Hamiltonian, including two- and three-nucleon potentials, and on realistic currents, consisting of one- and two-body terms. We find that the sum rules of the response functions associated with the longitudinal and transverse components of the (space-like) neutral current are largest and that a significant portion ($\\simeq 30$\\%) of the calculated strength is due to two-body terms. This fact may have implications for the MiniBooNE and other neutrino quasi-elastic scattering data on nuclei.
Compton scattering from 12C using tagged photons in the energy range 65 - 115 MeV
Myers, L S; Preston, M F; Anderson, M D; Annand, J R M; Boselli, M; Briscoe, W J; Brudvik, J; Capone, J I; Feldman, G; Fissum, K G; Hansen, K; Henshaw, S S; Isaksson, L; Jebali, R; Kovash, M A; Lewis, K; Lundin, M; MacGregor, I J D; Middleton, D G; Mittelberger, D E; Murray, M; Nathan, A M; Nutbeam, S; O'Rielly, G V; Schröder, B; Seitz, B; Stave, S C; Weller, H R
2014-01-01
Elastic scattering of photons from 12C has been investigated using quasi-monoenergetic tagged photons with energies in the range 65 - 115 MeV at laboratory angles of 60 deg, 120 deg, and 150 deg at the Tagged-Photon Facility at the MAX IV Laboratory in Lund, Sweden. A phenomenological model was employed to provide an estimate of the sensitivity of the 12C(g,g)12C cross section to the bound-nucleon polarizabilities.
Elastic Neutron Scattering at 96 MeV from {sup 12}C and {sup 208}Pb
Energy Technology Data Exchange (ETDEWEB)
Klug, J.; Blomgren, J.; Atac, A. [and others
2003-04-01
A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from {sup 12}C and {sup 208}Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory.
Elastic Neutron Scattering at 96 MeV from 12C and 208Pb
International Nuclear Information System (INIS)
A facility for detection of scattered neutrons in the energy interval 50-130 MeV, SCANDAL (SCAttered Nucleon Detection AssembLy), has recently been installed at the 20-180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from 12C and 208Pb has been studied at 96 MeV in the 10-70 deg interval. The achieved energy resolution, 3.7 MeV, is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated uncertainty, 3 %, is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions, based on phenomenology or microscopic nuclear theory
Elastic neutron scattering at 96 MeV from 12 C and 208 Pb
Klug, J.; Blomgren, J.; Ataç, A.; Bergenwall, B.; Hildebrand, A.; Johansson, C.; Mermod, P.; Nilsson, L.; Pomp, S.; Tippawan, U.; Elmgren, K.; Olsson, N.; Jonsson, O.; Prokofiev, A. V.; Renberg, P.-U.; Nadel-Turonski, P.; Dangtip, S.; Phansuke, P.; Österlund, M.; Le Brun, C.; Lecolley, J. F.; Lecolley, F. R.; Louvel, M.; Marie-Noury, N.; Schweitzer, C.; Eudes, Ph.; Haddad, F.; Lebrun, C.; Koning, A. J.; Ledoux, X.
2003-12-01
A facility for detection of scattered neutrons in the energy interval 50 130 MeV , SCANDAL, has recently been installed at the 20 180 MeV neutron beam line of the The Svedberg Laboratory, Uppsala. Elastic neutron scattering from 12 C and 208 Pb has been studied at 96 MeV in the 10° 70° interval. The achieved energy resolution, 3.7 MeV , is about an order of magnitude better than for any previous experiment above 65 MeV incident energy. The present experiment represents the highest neutron energy where the ground state has been resolved from the first excited state in neutron scattering. A novel method for normalization of the absolute scale of the cross section has been used. The estimated normalization uncertainty, 3% , is unprecedented for a neutron-induced differential cross section measurement on a nuclear target. The results are compared with modern optical model predictions based on phenomenology or microscopic nuclear theory.
He, W B; Cao, X G; Cai, X Z; Zhang, G Q
2014-01-01
It is studied how the $\\alpha$ cluster degrees of freedom, such as $\\alpha$ clustering configurations close to the $\\alpha$ decay threshold in $^{12}$C and $^{16}$O, including the linear chain, triangle, square, kite, and tetrahedron, affect nuclear collective vibrations with a microscopic dynamical approach, which can describe properties of nuclear ground states well across the nuclide chart and reproduce the standard giant dipole resonance (GDR) of $^{16}$O quite nicely. It is found that the GDR spectrum is highly fragmented into several apparent peaks due to the $\\alpha$ structure. The different $\\alpha$ cluster configurations in $^{12}$C and $^{16}$O have corresponding characteristic spectra of GDR. The number and centroid energies of peaks in the GDR spectra can be reasonably explained by the geometrical and dynamical symmetries of $\\alpha$ clustering configurations. Therefore, the GDR can be regarded as a very effective probe to diagnose the different $\\alpha$ cluster configurations in light nuclei.
Study of elastic [alpha]-scattering from [sup 2]H and [sup 12]C at E[sub [alpha
Energy Technology Data Exchange (ETDEWEB)
Morsch, H.P. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France) Inst. fuer Kernphysik, Forschungszentrum Juelich (Germany)); Boivin, M. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Boyard, J.L. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Fuchs, P. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Hennino, T. (Inst. de Physique Nucleaire, 91 Orsay (France)); Jaeckle, V. (Inst. fuer Kernphysik, Forschungszentrum Juelich (Germany)); Jourdain, J.C. (Inst. de Physique Nucleaire, 91 Orsay (France)); Kunne, R. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Murphy, L. (Physics Dept., Rensselaer Polytechnical Inst., Troy, NY (United States)); Plouin, F. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Radvanyi, P. (Lab. National Saturne, IN2P3-CNRS and DSM-CEA, 91 Gif-sur-Yvette (France)); Ramstein, B. (Inst. de
1994-11-01
Elastic scattering of [alpha]-particles from deuterium and [sup 12]C has been investigated using [alpha]-particles from Saturne. The differential cross sections have been analysed within an optical model description using a folding potential. Matter radii extracted at this energy are consistent with radii deduced from electron scattering. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Aguilera, E.F.; Lizcano, D.; Martinez Q, E.; Fernandez, M.C.; Murillo, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Goldberg, V. [Cyclotron Institute, Texas A and M University, College Station, TX 77843 (United States); Skorodumov, B.B.; Rogachev, G. [Physics Department, University of Notre Dame, IN 46556 (United States)
2003-07-01
The excitation function of elastic scattering for the system {sup 12} C + {sup 4} He to energy from 0.5 to 3.5 MeV in the center of mass system (c.m.) was measured. We use a gassy thick target and the technique of inverse kinematics which allows to make measurements at 180 degrees in c.m. Using the R matrix theory those was deduced parameters of the resonances and the results were compared with measurements reported in the literature made with other techniques. (Author)
Energy Technology Data Exchange (ETDEWEB)
Ou, I.; Yamada, Y.; Mori, T.; Yano, T.; Sakuda, M. [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Tamii, A.; Suzuki, T.; Yosoi, M.; Aoi, N.; Ideguchi, E.; Hashimoto, T.; Miki, K.; Ito, T.; Iwamoto, C.; Yamamoto, T. [Research Center for Nuclear Physics (RCNP), Osaka University, Ibaraki, Osaka 567-0047 (Japan); Akimune, H. [Department of Physics, Konan University, Okamoto 8-9-1, Higashinada, Kobe 658-8501 (Japan)
2015-05-15
We propose to measure the γ-ray emission probability from excited states above 5 MeV including giant resonance of {sup 16}O and {sup 12}C as a function of excitation energy in 1-MeV step. Here, we measure both the excitation energy (E{sub x}=5-30MeV) at the forward scattering angles (0°-3°) of the {sup 16}O, {sup 12}C (p, p’) reaction using Grand-Raiden Spectrometer and the energy of γ-rays (E{sub γ}) using an array of NaI(Tl) counters. The purpose of the experiment is to provide the basic and important information not only for the γ-ray production from primary neutral-current neutrino-oxygen (-carbon) interactions but also for that from the secondary hadronic (neutron-oxygen and -carbon) interactions.
International Nuclear Information System (INIS)
We propose to measure the γ-ray emission probability from excited states above 5 MeV including giant resonance of 16O and 12C as a function of excitation energy in 1-MeV step. Here, we measure both the excitation energy (Ex=5-30MeV) at the forward scattering angles (0°-3°) of the 16O, 12C (p, p’) reaction using Grand-Raiden Spectrometer and the energy of γ-rays (Eγ) using an array of NaI(Tl) counters. The purpose of the experiment is to provide the basic and important information not only for the γ-ray production from primary neutral-current neutrino-oxygen (-carbon) interactions but also for that from the secondary hadronic (neutron-oxygen and -carbon) interactions
Resonantly scattering crystals and surfaces
International Nuclear Information System (INIS)
We examine coherence effects from forming a crystal of resonant scatterers by generalising the Fano model for autoionising resonances in electron scattering from atoms to a lattice of such scatterers. (We have in mind the case of neutron scattering from nuclei.) We solve this problem to yield two branches to the dispersion relation for the neutron in general and three when the resonance coincides with a Brillouin Zone boundary. The 'width' of the resonance is enhanced over the isolated nucleus, the best candidate for observation being the 2eV 185Re resonance near the Bragg condition. We use these results to calculate the reflection coefficient from a surface, revealing total external reflection near resonance. We discuss experimental feasibility in both the neutron and electron cases. (author)
Scattering of solitons on resonance
Kiselev, O M; Glebov, S. G.
2004-01-01
We investigate a propagation of solitons for nonlinear Schrodinger equation under small driving force. The driving force passes the resonance. The process of scattering on the resonance leads to changing of number of solitons. After the resonance the number of solitons depends on the amplitude of the driving force.
Quasi-bound alpha resonant states populated by the {sup 12}C({sup 6}Li, d) reaction
Energy Technology Data Exchange (ETDEWEB)
Rodrigues, M.R.D.; Borello-Lewin, T.; Miyake, H.; Horodynski-Matsushigue, L.B.; Duarte, J.L.M.; Rodrigues, C.L.; Souza, M.A. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica; Cunsolo, A.; Cappuzzello, F.; Foti, A.; Agodi, C.; Cavallaro, M. [Istituto Nazionale di Fisica Nucleare (LNS/INFN), Catania (Italy). Lab. Nazionali del Sud; Ukita, G.M. [Universidade de Santo Amaro (UNISA), Sao Paulo, SP (Brazil). Faculdade de Psicologia
2012-07-01
Full text: The alpha cluster phenomenon in the light nuclei structure has been the subject of a long time investigation since the proposal of the Ikeda diagrams [1]. The main purpose of the research program in progress is the investigation of this phenomenon in (x{alpha}) and (x{alpha}+n) nuclei through the ({sup 6}Li, d) alpha transfer reaction [2-4]. Alpha resonant states around the (4{alpha}) threshold in the nucleus {sup 16}O are the focus of the present contribution. In fact, the importance of these resonances at the elements production in stars is recognized, as primarily pointed out by Hoyle in {sup 12}C [6]. The existence of a rotational band with the {alpha} +{sup 12} C (Hoyle) cluster state structure was recently demonstrated by Ohkubo and Hirabayashi [6]. In order to explore this region of interest, measurements of the {sup 12}C({sup 6}Li, d){sup 16}O reaction up to 17 MeV of excitation at an incident energy of 25.5 MeV, have been performed employing the Sao Paulo Pelletron-Enge Split-Pole facility and the nuclear emulsion detection technique (plates Fuji G6B, 50 {mu}m thick). Spectra associated with six scattering angles, from 5 deg to 29 deg in the laboratory frame, each one 50 cm along the focal surface, were measured. Several narrow resonances with a quasi-bound behavior embedded in the continuum were detected and the resolution of 25 keV allowed for the separation of doublets not resolved before [7,8]. The absolute cross sections and the respective deuteron angular distributions were determined and the analysis is in progress. [1] K. Ikeda et al., Prog. Theor. Phys. Suppl. E 68, 464 (1968); H. Horiuchi, K. Ikeda, and Y. Suzuki, ibid. 44, 225 (1978). [2] M.R.D.Rodrigues et al., in12th International Conference on Nuclear Reaction Mechanism, Varenna, Italy, edited by F. Cerutti and A. Ferrari , CERN Proceedings, 2010-2, pp. 331- 335. [3] T. Borello-Lewin et al., Proceedings of SOTANCP2, Brussels, Belgium 2010, edited by P. Descouvemount et al., Int. J
Quasi-Elastic Scattering of 16C from 12C at 47.5 MeV/Nucleon
Institute of Scientific and Technical Information of China (English)
FAN Feng-Ying; ZHENG Tao; YE Yan-Lin; JIANG Dong-Xing; HUA Hui; LI Zhi-Huan; GE Yu-Cheng; LI Xiang-Qing; LOU Jian-Ling; SHI Fan; LV Lin-Hui; CAO Zhong-Xin; NIE Peng-Xuan; LI Qi-Te; SONG Yu-Shou; LU Fei; XU Hu-Shan; HU Zheng-Guo; WANG Meng; ZHANG Xue-Ying; LI Chen; CHEN Ruo-Fu; TANG Bin; XU Zhi-Guo; YUE Ke; ZHANG Ya-Peng; ZANG Yong-Dong; ZHANG Xue-Heng; YAO Xiang-Wu; CHEN Jin-Da; TU Xiao-Lin; ZHANG Jie; WU Da-Peng; BAI Zhen
2009-01-01
Differential cross sections for the quasi-elastic scattering of 16C at 47.5 MeV/nucleon from 12C target are measured.Coupled-channels calculations are carried out and the optical potential parameters are obtained by fitting the experimental angular distribution.
Elastic and inelastic scattering of 800 MeV/c K+- mesons from 12C and 40Ca
International Nuclear Information System (INIS)
Methods and results of an experiment to study the scattering of 800 MeV/c K+- mesons from 12C and 40Ca are presented. The reactions under study include: the four elastic scattering reactions 12C(K+-,K+-) and 40Ca(K+-,K+-), and the four inelastic scattering reactions, 12C(K+-.K+-') to the J/sup P/ = 2+ 4.43 MeV and J/sup P/ = 3- states. The experimental data were obtained using the Hyper-Nuclear Spectrometer and the Low Energy Separated Beam (LESB I) at the Alternating Gradient Synchrotron (AGS) of Brookhaven Laboratory (BNL). Calculations using the program PIRK, an optical potential code, are compared to the elastic data. The results of a second set of calculations, using Glauber theory are also presented. Both sets of calculations use as input: the results of partial wave analyses of kaon nucleon scattering data, and nuclear shapes as determined from the results of electron nucleus scattering experiments. The agreement between the experimental data and the theoretical predictions is reasonable over the angular range of the data, with the exception of Glauber calculations of the K+ elastic scattering. In those cases, the eikonal approximation proves to be a poor approximation. Smaller discrepancies are found in some other cases, indicating the possible need for more sophisticated calculations
(π±, π±' N) reactions on 12C and 208Pb near the giant resonance region
International Nuclear Information System (INIS)
Angular distributions for the 12C(π±, π±' p) and 208Pb(π±, π±' p or n) reactions near the giant resonance region have been measured at Tπ = 180 MeV, and found different between π+ and π- data. This observation is interpreted as evidence for different excitation mechanisms dominating the π--nucleus and π+-nucleus interactions in the giant resonance region of these targets. A comparison with the single-nucleon knock-out distorted-wave impulse approximation calculations shows, even though these calculations underestimate (π±, π±' N) data for both targets, the dominance of direct process for (π+, π+' p) or (π-, π-' n) in contrast to (π-, π-' p) or (π+, π+' n). In the (π+, π+' p) reaction proton-proton hole states are excited directly and appear to have a large probability for direct decay with escape width, whereas in (π-, π-' p) the preferentially excited neutron-neutron hole doorway states couple to resonance states and decay with spreading width. This interpretation led us to suggest that the ratio of cross-sections for inelastic scattering to the giant resonance region should be written in terms of an incoherent sum of cross-sections to neutron and proton doorway states. In a heavy nucleus such as 208Pb, neutron and proton doorway states. In a heavy nucleus such as 208Pb, neutron and proton doorway states contribute incoherently because the different decay processes do not populate the same final states of the residual nucleus
Nanocatalytic resonance scattering spectral analysis
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
The resonance scattering spectral technique has been established using the synchronous scanning technique on spectrofluorometry.Because of its advantages of simplicity,rapidity and sensitivity,it has been widely applied to analyses of proteins,nucleic acids and inorganic ions.This paper summarizes the application of immunonanogold and aptamer modified nanogold(AptAu) catalytic resonance scattering spectral technique in combination with the work of our group,citing 53 references.
Quasi-elastic scattering of 6He, 7Be, and 8B nuclei by 12C nuclei
Kovalchuk, V I
2016-01-01
The observed cross sections of quasi-elastic scattering of 6He, 7Be, and 8B nuclei by 12C nuclei are described within the framework of the diffraction nuclear model and the model of nucleus-nucleus scattering in the high-energy approximation with a double folding potential, for intermediate energies of the incident particles. The calculations make use of realistic distributions of nucleon densities and take account of the Coulomb interaction and inelastic scattering with excitation of low-lying collective states of the target.
Indian Academy of Sciences (India)
I Ahmad; M R Arafah
2006-03-01
Elastic scattering of 800 MeV/c pions by 12C has been studied in the diffraction model with a view to determine pion optical potential by the method of inversion. Finding an earlier diffraction model analysis to be deficient in some respects, we propose a Glauber model based parametrization for the elastic -matrix and show that it provides an exceedingly good fit to the pion-carbon data. The proposed elastic -matrix gives a closed expression for the pion-12C optical potential by the method of inversion in the high energy approximation.
Isoscalar monopole and dipole excitations of cluster states and giant resonances in $^{12}$C
Kanada-En'yo, Yoshiko
2015-01-01
The isoscalar monopole(ISM) and dipole(ISD) excitations in $^{12}$C are theoretically investigated with the shifted antisymmetrized molecular dynamics(AMD) plus $3\\alpha$-cluster generator coordinate method(GCM). The small amplitude vibration modes are described by coherent one-particle one-hole excitations expressed by small shift of single-nucleon Gaussian wave functions within the AMD framework, whereas the large amplitude cluster modes are incorporated by superposing $3\\alpha$-cluster wave functions in the GCM. The coupling of the excitations in the intrinsic frame with the rotation and parity transformation is taken into account microscopically by the angular-momentum and parity projections. The present calculation describes the ISM and ISD excitations in a wide energy region covering cluster modes in the low-energy region and the giant resonances in the high-energy region, though the quantitative description of the high-energy part is not satisfactory. The low-energy ISM and ISD strengths of the cluster...
Measurement of quasi-elastic 12C(p,2p) scattering at high momentum transfer
Mardor, Y.; Aclander, J.; Alster, J.; Barton, D; Bunce, G.; Carroll, A.; Christensen, N.; Courant, H.; Durrant, S.; Gushue, S.; Heppelmann, S.; Kosonovsky, E.; Mardor, I.; Marshak, M.; Makdisi, Y.
1997-01-01
We measured the high-momentum quasi-elastic 12C(p,2p) reaction (at center of mass angle near 90 degrees) for 6 and 7.5 GeV/c incident protons. The three-momentum components of both final state protons were measured and the missing energy and momentum of the target proton in the nucleus were determined. The validity of the quasi-elastic picture was verified up to Fermi momenta of about 450 MeV/c, where it might be questionable. Transverse and longitudinal Fermi momentum distributions of the ta...
Energy Technology Data Exchange (ETDEWEB)
Yoo, Sung Hoon.
1990-05-01
Angular distributions for the {sup 12}C({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} p) and {sup 208}Pb({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} p or n) reactions near the giant resonance region have been measured at T{sub {pi}} = 180 MeV, and found different between {pi}{sup +} and {pi}{sup {minus}} data. This observation is interpreted as evidence for different excitation mechanisms dominating the {pi}{sup {minus}}-nucleus and {pi}{sup +}-nucleus interactions in the giant resonance region of these targets. A comparison with the single-nucleon knock-out distorted-wave impulse approximation calculations shows, even though these calculations underestimate ({pi}{sup {plus minus}}, {pi}{sup {plus minus}}{prime} N) data for both targets, the dominance of direct process for ({pi}{sup +}, {pi}{sup {plus}}{prime} p) or ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} n) in contrast to ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} p) or ({pi}{sup +}, {pi}{sup +}{prime} n). In the ({pi}{sup +}, {pi}{sup +}{prime} p) reaction proton-proton hole states are excited directly and appear to have a large probability for direct decay with escape width, whereas in ({pi}{sup {minus}}, {pi}{sup {minus}}{prime} p) the preferentially excited neutron-neutron hole doorway states couple to resonance states and decay with spreading width. This interpretation led us to suggest that the ratio of cross-sections for inelastic scattering to the giant resonance region should be written in terms of an incoherent sum of cross-sections to neutron and proton doorway states. In a heavy nucleus such as {sup 208}Pb, neutron and proton doorway states. In a heavy nucleus such as {sup 208}Pb, neutron and proton doorway states contribute incoherently because the different decay processes do not populate the same final states of the residual nucleus.
Neutron scattering from 12C in the few-MeV region
International Nuclear Information System (INIS)
Neutron total cross sections of natural carbon are deduced from the observed transmission of approximately monoenergetic neutrons through carbon samples of varying thickness. The measurements extend from approximately equal to 0.1 to 4.5 MeV with resolutions of approximately equal to 2 to 100 keV. Neutron differential-elastic-scattering cross sections of natural carbon are measured from 1.5 to 4.0 MeV at incident-neutron energy intervals of approximately less than 100 keV, over an angular range of approximately equal to 20 to 1600 and with energy resolutions of 20 to 50 keV. The experimental results are interpreted in terms of a multilevel R-function analysis. Results are compared with the large body of measured and evaluated neutron total and scattering cross sections and scattered neutron polarizations reported in the literature. It is suggested that the observed neutron total and scattering cross sections of carbon are physically consistent and suitable for use as a reference standard in experimental studies of neutron processes. The R-function description should provide a convenient description of neutron total and scattering cross sections of carbon as a function of both angle and energy. 88 references
Elastic scattering of intermediate energy protons on 4He and 12C
International Nuclear Information System (INIS)
The elastic angular distribution and polarization of 1.04 GeV protons on 4He and 12C have been analysed using the recently proposed correlated expansion for the Glauber amplitude by retaining terms up to three-body density only. The calculations include Coulomb and spin effects. Using realistic form factors for target nuclei it is found that we need to consider only up to the second-order density term to provide a satisfactory explanation of both kinds of experimental data in the available momentum transfer region. The contribution of the three-body density term is only marginal except in 4He differential cross-section in the c.m. angular range 4500. (author)
Matsumoto, T; Ogata, K; Iseri, Y; Kamimura, M; Chiba, S; Yahiro, M
2004-01-01
We propose a fully quantum-mechanical method of treating four-body nuclear breakup processes in scattering of a projectile consisting of three constituents, by extending the continuum-discretized coupled-channels method. The three-body continuum states of the projectile are discretized by diagonalizing the internal Hamiltonian of the projectile with the Gaussian basis functions. For $^6$He+$^{12}$C scattering at 18 and 229.8 MeV, the validity of the method is tested by convergence of the elastic and breakup cross sections with respect to increasing the number of the basis functions. Effects of the four-body breakup and the Borromean structure of $^6$He on the elastic and total reaction cross sections are discussed.
Energy Technology Data Exchange (ETDEWEB)
Couture, Aaron Joseph [Los Alamos National Laboratory; Detwiler, Rebecca [UNIV OF FL; Gorres, Joachim [UNIV OF NOTRE DAME; Stech, Edward J [UNIV OF NOTRE DAME; Ugalde, Claudio [UNIV OF NOTRE DAME; Wiescher, Michael C F [UNIV OF NOTRE DAME; Heil, Michael [GSI DARMSTADT; Kappeler, Franz [FORSCHUNGSZENTRUM KARLSRUHE; Azuma, Richard E [UNIV OF TORONTO; Buchmann, Lothar [TRIUMF
2009-01-01
Recent global analyses of {sup 12}C({alpha},{gamma}){sup 16}O have incorporated both elastic-scallering and {beta}-decay data in addition to direct measurements. In that context, it has been shown that an improvement in the available elastic-scallering data could help determine the contribution of the two subthreshold states, 6.92(2{sup +}) and 7.12(1{sup -}) MeV, and with excellent statistics could restrict resonance parameters above the threshold. To this end angular distributions of {sup 12}C({alpha}, {alpha}){sup 12}C in the {alpha}-energy range of 2.6-8.2 MeV, at angles from 24 to 166 have been measured at the University of Notre Dame using an array of 32 silicon detectors. Details of the experiment are reported. In the present analysis, the phase shifts have been determined from our previously reported R-matrix fit to these data. The uncertainties in the R-matrix phase shifts ({ell} = 0...6) are derived by a new Monte Carlo analysis technique as described in the article. We provide these phase shifts here for general use, in particular for the improved analysis and extrapolation of the {alpha} radiative capture to low energies.
{sup 16}O resonances near 4α threshold through {sup 12}C({sup 6}Li,d) reaction
Energy Technology Data Exchange (ETDEWEB)
Rodrigues, M. R. D.; Borello-Lewin, T.; Miyake, H.; Horodynski-Matsushigue, L. B.; Duarte, J. L. M.; Rodrigues, C. L.; Faria, P. Neto de [Instituto de Física, Universidade de São Paulo, Caixa Postal 66318, CEP 05314-970, São Paulo, SP (Brazil); Cunsolo, A.; Cappuzzello, F.; Foti, A.; Agodi, C.; Cavallaro, M. [INFN - Laboratori Nazionali del Sud, Via S. Sofia 62, 95125 Catania (Italy); Napoli, M. di; Ukita, G. M. [Faculdade de Psicologia, Universidade de Santo Amaro, R. Prof. Eneas da Siqueira Neto, 340, CEP 04829-300, São Paulo, SP (Brazil)
2014-11-11
Several narrow alpha resonant {sup 16}O states were detected through the {sup 12}C({sup 6}Li,d) reaction, in the range of 13.5 to 17.5 MeV of excitation energy. The reaction was measured at a bombarding energy of 25.5 MeV employing the São Paulo Pelletron-Enge-Spectrograph facility and the nuclear emulsion technique. Experimental angular distributions associated with natural parity quasi-bound states around the 4α threshold are presented and compared to DWBA predictions. The upper limit for the resonance widths obtained is near the energy resolution (15 keV)
Elastic and inelastic scattering of 400 MeV polarised deuterons on 12C, 24Mg, 40Ca nuclei
International Nuclear Information System (INIS)
This research thesis is based on an experiment of scattering of polarised 400 MeV deuterons on 12C, 24Mg, 40Ca nuclei, performed on the Saturne accelerator. The measured observables are the non-polarised cross section, and the powers of vector and tensor analysis. The author describes the experiment running and the installation, presents the various devices from source to detection and acquisition by the computer system. He reports the experiment compilation: reading of magnetic tapes, assessment and taking into account of the different experimental parameters. The calculation of scattering observables (cross section and powers of analysis) is performed by using experimental data. Spectra of these observables are represented for the different excited states of nuclei, after, should the occasion arise, Gaussian decomposition or background subtraction. The author reports the analysis of the obtained results. Results obtained for the three nuclei are compared between each other, and with scattering data for protons at similar energies which have already been measured. An analysis with a microscopic model is performed and the predictions of this model are compared with the obtained results
Second order resonant Raman scattering
Energy Technology Data Exchange (ETDEWEB)
Garcia-Cristobal, A.; Catarero, A. [Valencia Univ. (Spain). Dept. de Fisica Aplicada; Trallero-Giner, C. [Instituto Politecnico Nacional, Mexico City (Mexico). Centro de Investigacion y de Estudios Avanzados
1996-03-01
A theoretical model for resonant Raman scattering by two optical phonons in zincblende-type semiconductors is presented. The effect of Coulomb interaction between electrons and holes is taken into account by introducing discrete and continuous excitonic intermediate states. The model can be applied for laser frequencies below and above the band gap. We consider deformation potential and Froehlich interaction for the electron-one-phonon coupling. The absolute value of the scattering efficiency is evaluated for the L-O-phonons, TO-plus LO-phonon and two-TO-photons Raman processes, around the E{sub o} absorption edge of II-VI compound semiconductors. Comparison with the electron-hole uncorrelated theory and experimental data emphasizes the role if the excitonic effects. (author). 10 refs., 2 figs.
Ivanov, M. V.; Antonov, A. N.; Caballero, J. A.; Megias, G. D.; Barbaro, M. B.; de Guerra, E. Moya; Udías, J. M.
2014-01-01
Charge-current quasielastic (anti)neutrino scattering cross sections on a 12C target are analyzed using a spectral function S (p,E) that gives a scaling function in accordance with the (e ,e') scattering data. The spectral function accounts for the nucleon-nucleon (NN) correlations, it has a realistic energy dependence, and natural orbitals (NOs) from the Jastrow correlation method are used in its construction. In all calculations the standard value of the axial mass MA=1.032 GeV/c2 is used. The results are compared with those when NN correlations are not included, as in the relativistic Fermi gas model, or when harmonic-oscillator single-particle wave functions are used instead of NOs. The role of the final-state interactions (FSIs) on the theoretical spectral and scaling functions, as well as on the cross sections, is accounted for. A comparison of the results for the cases with and without FSI, as well as to results from the phenomenological scaling function obtained from the superscaling analysis, is carried out. Our calculations based on the impulse approximation underpredict the MiniBooNE data but agree with the data from the NOMAD experiment. The possible missing ingredients in the considered theoretical models are discussed.
Cascades of Fano resonances in Mie scattering
Rybin, M. V.; Sinev, I. S.; Samusev, K. B.; Limonov, M. F.
2014-03-01
The interference nature of resonant Mie scattering, which is described within the Fano model, has been demonstrated. The interference is caused by interaction of an incident electromagnetic wave with reemitted waves that correspond to eigenmodes of a scattering particle. Mie scattering due to the interference can be represented in the form of cascades of resonance lines of different shapes, each of which is described by the classical Fano formula. The effect is observed in resonant light scattering by an arbitrary body of revolution and discussed in detail using the example of scattering by an infinite homogeneous dielectric cylinder.
Reinhardt, Tobias P; Bemmerer, Daniel; Stöckel, Klaus; Wagner, Louis
2016-01-01
Resonant nuclear reactions are a powerful tool for the determination of the amount and profile of hydrogen in thin layers of material. Usually, this tool requires the use of a standard of well-known composition. The present work, by contrast, deals with standard-less hydrogen depth profiling. This approach requires precise nuclear data, e.g. on the widely used $^{1}$H($^{15}$N,$\\alpha\\gamma$)$^{12}$C reaction, resonant at 6.4\\,MeV $^{15}$N beam energy. Here, the strongly anisotropic angular distribution of the emitted $\\gamma$-rays from this resonance has been re-measured, resolving a previous discrepancy. Coefficients of (0.38$\\pm$0.04) and (0.80$\\pm$0.04) have been deduced for the second and fourth order Legendre polynomials, respectively. In addition, the resonance strength has been re-evaluated to (25.0$\\pm$1.5)\\,eV, 10\\% higher than previously reported. A simple working formula for the hydrogen concentration is given for cases with known $\\gamma$-ray detection efficiency. Finally, the absolute approach i...
Absolute hydrogen depth profiling using the resonant 1H(15N, αγ)12C nuclear reaction
Reinhardt, Tobias P.; Akhmadaliev, Shavkat; Bemmerer, Daniel; Stöckel, Klaus; Wagner, Louis
2016-08-01
Resonant nuclear reactions are a powerful tool for the determination of the amount and profile of hydrogen in thin layers of material. Usually, this tool requires the use of a standard of well-known composition. The present work, by contrast, deals with standard-less hydrogen depth profiling. This approach requires precise nuclear data, e.g. on the widely used 1 H(15 N, αγ)12 C reaction, resonant at 6.4 MeV 15 N beam energy. Here, the strongly anisotropic angular distribution of the emitted γ -rays from this resonance has been re-measured, resolving a previous discrepancy. Coefficients of (0.38 ± 0.04) and (0.80 ± 0.04) have been deduced for the second and fourth order Legendre polynomials, respectively. In addition, the resonance strength has been re-evaluated to (25.0 ± 1.5) eV, 10% higher than previously reported. A simple working formula for the hydrogen concentration is given for cases with known γ -ray detection efficiency. Finally, the absolute approach is illustrated using two examples.
Energy Technology Data Exchange (ETDEWEB)
Gersch, H.U.; Schobbert, H.; Wohlfarth, D. (Zentralinstitut fuer Kernforschung, Rossendorf bei Dresden (German Democratic Republic))
1983-08-01
The 11.1 MeV 5/sup -/ resonance in the /sup 12/C + /sup 16/O reaction is remeasured and the position of the resonance is determined to be Esub(x)(/sup 28/Si) = (27.881 +- 0.022)MeV. A kinematically complete study of the /sup 12/C(/sup 16/O, ..cap alpha../sup 12/C)/sup 12/C reaction into this resonance is carried out. Particle identification is based on the reaction kinematics. No evidence for a /sup 12/C-..cap alpha..-/sup 12/C component of this resonance is found.
Resonances in Positron-Mg Scattering
Institute of Scientific and Technical Information of China (English)
PENG Yue; CHENG Cheng; ZHOU Ya-Jun
2007-01-01
We present the results for resonances in positron-Mg scattering at low impact energy (0-5.0eV) by using the momentum space coupled-channel optical (CCO) method in momentum space. The S-partial wave resonance at 3.880eV, P-partial wave resonance at 4.020eV, and D-partial wave resonance at 4.267eV are found.
Resonant X-Ray Scattering and Absorption
Collins, S. P.; Bombardi, A.
This chapter outlines some of the basic ideas behind nonresonant and resonant X-ray scattering, using classical or semiclassical pictures wherever possible; specifically, we highlight symmetry arguments governing the observation of X-ray optical effects, such as X-ray magnetic circular dichroism and resonant "forbidden" diffraction. Without dwelling on the microscopic physics that underlies resonant scattering, we outline some key steps required for calculating its rotation and polarization dependence, based on Cartesian and spherical tensor frameworks. Several examples of resonant scattering, involving electronic anisotropy and magnetism, are given as illustrations. Our goal is not to develop or defend theoretical concepts in X-ray scattering, but to bring together existing ideas in a pragmatic and utilitarian manner.
Energy Technology Data Exchange (ETDEWEB)
Wilson, David J. [Old Dominion University, Norfolk, VA
2014-06-23
We have obtained clear signals of resonances in coupled-channel pi K - eta K scattering. Using distillation and a large basis of operators we are able to extract a precise spectrum of energy levels using the variational method. These energies are analysed using inelastic extensions of the Luescher method to obtain scattering amplitudes that clearly describe S, P and D wave resonances, corresponding to the physical K_0^*(1430), the K^*(892) and the K_2^*(1430).
Resonances in Positron-He Scattering
Institute of Scientific and Technical Information of China (English)
XIAO Dan; JIANG Ping-Hui; ZHOU Ya-Jun
2007-01-01
We present the results for resonances in positron-He scattering at low impact energy (19.3-24.0eV) by using the momentum space coupled-channel optical (CCO) method. The S-partial wave resonance at 20.16eV is found for the first time.
Multi-cluster problems: resonances, scattering and condensed states
International Nuclear Information System (INIS)
This talk is mainly concerned with many-body resonances in nuclear physics. We extensively discuss the structure and reactions of multi-cluster systems using the complex scaling method (CSM). We expound three interesting problems in recent studies of multi-cluster systems. First, we discuss four- and five-body resonances in A=7 (7He, 7B) and A=8 (8He, 8C) systems, respectively. The observed states are well explained and many additional states are predicted. Second, the Coulomb breakup reactions of two-neutron halo nuclei and the α-d scattering are investigated using a three-body model with CSM. Finally, we discuss the α-condensate-like states and their symplectic excitation properties in three- and four-α models for 12C and 16O, respectively.
Measurements of the neutron scattering cross sections for 12C, 16O, 40Ca and 56Fe at 14.2 MeV
International Nuclear Information System (INIS)
Double different cross sections and energy-integrated differential ones for elastic and inelastic scattering from 12C, 16O, 40Ca, and 56Fe at 14.2 MeV have been measured at forward angles from 10O to 70O in 10O steps. The experimental data have been compared with the predictions of JENDL-3 as well as those of optical model and DWBA calculations. (author)
Hadron scattering and resonances in QCD
Energy Technology Data Exchange (ETDEWEB)
Dudek, Jozef J. [Old Dominion Univ., Norfolk, VA (United States)
2016-05-01
I describe how hadron-hadron scattering amplitudes are related to the eigenstates of QCD in a finite cubic volume. The discrete spectrum of such eigenstates can be determined from correlation functions computed using lattice QCD, and the corresponding scattering amplitudes extracted. I review results from the Hadron Spectrum Collaboration who have used these finite volume methods to study pi pi elastic scattering, including the rho resonance, as well as coupled-channel pi K, eta K scattering. Ongoing calculations are advertised and the outlook for finite volume approaches is presented.
Hadron scattering and resonances in QCD
Dudek, Jozef J.
2016-05-01
I describe how hadron-hadron scattering amplitudes are related to the eigenstates of QCD in a finite cubic volume. The discrete spectrum of such eigenstates can be determined from correlation functions computed using lattice QCD, and the corresponding scattering amplitudes extracted. I review results from the Hadron Spectrum Collaboration who have used these finite volume methods to study ππ elastic scattering, including the ρ resonance, as well as coupled-channel π >K, ηK scattering. Ongoing calculations are advertised and the outlook for finite volume approaches is presented.
Evidence for L -dependence generated by channel coupling: 16O scattering from 12C at 115.9 MeV
Mackintosh, R. S.
2016-09-01
Background: In earlier work, inversion of S matrix for 330 MeV 16O on 12C resulted in highly undulatory potentials; the S matrix resulted from the inclusion of strong coupling to states of projectile and target nuclei. L -independent S -matrix equivalent potentials for other explicitly L -dependent potentials have been found to be undulatory. Purpose: To investigate the possible implications of the undulatory dynamic polarization potential for an underlying L dependence of the 16O on 12C optical potential. Methods: S matrix to potential, SL→V (r ) , inversion which yields local potentials that reproduce the elastic channel S matrix of coupled channel (CC) calculations, will be applied to the S matrix for 115.9 MeV 16O on 12C. Further, SL for explicitly L -dependent potentials are inverted and the resulting L -independent potentials are characterized and compared with the undulatory potentials found for 16O on 12C. Results: Some of the undulatory features exhibited by the potentials modified by channel coupling for 115.9 MeV 16O on 12C can be simulated by simple parameterized L -dependent potentials. Conclusions: The elastic scattering of 16O by 12C is a particularly favorable case for revealing the effective L dependence of the potential modified by channel coupling. Nevertheless, there is no reason to suppose that undularity is not a generic property leading in many cases to the choice: nucleus-nucleus potentials are (i) smooth and L -dependent, (ii) L -independent and undulatory, or (iii) both.
Inelastic scattering in resonant tunneling
DEFF Research Database (Denmark)
Wingreen, Ned S.; Jacobsen, Karsten Wedel; Wilkins, John W.
1989-01-01
The exact resonant-tunneling transmission probability for an electron interacting with phonons is presented in the limit that the elastic coupling to the leads is independent of energy. The phonons produce transmission sidebands but do not affect the integrated transmission probability or the esc......The exact resonant-tunneling transmission probability for an electron interacting with phonons is presented in the limit that the elastic coupling to the leads is independent of energy. The phonons produce transmission sidebands but do not affect the integrated transmission probability...
Resonance scattering spectroscopy of gold nanoparticle
Institute of Scientific and Technical Information of China (English)
JIANG; Zhiliang; FENG; Zhongwei; LI; Tingsheng; LI; Fang; ZHONG; Fuxin; XIE; Jiyun; YI; Xianghui
2001-01-01
The gold nanoparticles in diameter of 10-95 nm have been prepared by Frens procedure, all of which exhibit a resonance scattering peak at 580 nm. The mechanism of resonance scattering for gold nanoparticle has been considered according to the wave motion theory of nanoparticle in liquid. The principle of superamolecular interface energy band(SIEB) has been set up and utilized to explain the relationship between the diameter and colors for gold nanoparticle in liquid. A novel spectrophotometric ruler for the determination of the diameter has been proposed according to the relationship of the maximum absorption wavelength and diameter.
Scattering by coupled resonating elements in air
Krynkin, Anton; Chong, Alvin Y B; Taherzadeh, Shahram; Attenborough, Keith
2011-01-01
Scattering by (a) a single composite scatterer consisting of a concentric arrangement of an outer N-slit rigid cylinder and an inner cylinder which is either rigid or in the form of a thin elastic shell and (b) by a finite periodic array of these scatterers in air has been investigated analytically and through laboratory experiments. The composite scatterer forms a system of coupled resonators and gives rise to multiple low frequency resonances. The corresponding analytical model employs polar angle dependent boundary conditions on the surface of the N-slit cylinder. The solution inside the slits assumes plane waves. It is shown also that in the low-frequency range the N-slit rigid cylinder can be replaced by an equivalent fluid layer. Further approximations suggest a simple square root dependence of the resonant frequencies on the number of slits and this is confirmed by data. The observed resonant phenomena are associated with Helmholtz-like behaviour of the resonator for which the radius and width of the o...
Resonance Light Scattering Imaging Determination of Heparin
Institute of Scientific and Technical Information of China (English)
Hong Ping GUO; Cheng Zhi HUANG; Jian LING
2006-01-01
A laser-induced resonance light scattering (RLS) imaging method to determine heparin is described based on the high light scattering emission power of the aggregation species of heparin with α, β, γ, δtetra(4-trimethylaminoniumphenyl)prophyrin (TAPP) in solution. By imaging the light scattering signals of the aggregation species, we proposed the method to determine the heparin with a detection range of 0.02 - 0.6 μg/mL and the detection limit (3 σ) of 1.3 ng/mL.
Energy Technology Data Exchange (ETDEWEB)
Csedreki, L., E-mail: csedreki@atomki.mta.hu [Institute for Nuclear Research, Hungarian Academy of Sciences, MTA Atomki, H-4001 Debrecen, P.O. Box 51 (Hungary); Szíki, G.Á. [University of Debrecen, Faculty of Engineering, Department of Basic Technical Studies, H-4028 Debrecen, Ótemető u. 2-4 (Hungary); Szikszai, Z. [Institute for Nuclear Research, Hungarian Academy of Sciences, MTA Atomki, H-4001 Debrecen, P.O. Box 51 (Hungary); Kocsis, I. [University of Debrecen, Faculty of Engineering, Department of Basic Technical Studies, H-4028 Debrecen, Ótemető u. 2-4 (Hungary)
2015-01-01
The observed resonance parameters of the {sup 12}C(d,pγ){sup 13}C reaction in the vicinity of 1450 keV deuteron energy have been determined in a thorough procedure, fitting our recent experimental excitation curve, as well as earlier literature data with the Root Software Package. The resulting energy and width (FWHM) of resonance are 1445.8 ± 0.2 keV and 5.3 ± 0.4 keV, respectively. We propose the application of this resonance as a precise and simple method for accelerator energy calibration when performing DIGE analysis.
Controlling electromagnetic scattering with wire metamaterial resonators
Filonov, Dmitry S; Iorsh, Ivan; Belov, Pavel A; Ginzburg, Pavel
2016-01-01
Manipulation of radiation is required for enabling a span of electromagnetic applications. Since properties of antennas and scatterers are very sensitive to a surrounding environment, macroscopic artificially created materials are good candidates for shaping their characteristics. In particular, metamaterials enable controlling both dispersion and density of electromagnetic states, available for scattering from an object. As the result, properly designed electromagnetic environment could govern waves' phenomena. Here electromagnetic properties of scattering dipoles, situated inside a wire medium (metamaterial) are analyzed both numerically and experimentally. Impact of the metamaterial geometry, dipole arrangement inside the medium, and frequency of the incident radiation on scattering phenomena was studied. It was shown that the resonance of the dipole hybridizes with Fabry-Perot modes of the metamaterial, giving rise to a complete reshaping of electromagnetic properties. Regimes of controlled scattering sup...
Elastic scattering for 16O + 12C at 140 MeV and 218 MeV
International Nuclear Information System (INIS)
In this work, angular distribution of cross sections have been measured for 12C(16O,16O)12C at two energies. The measurements were carried out in 0.50 intervals between 50-19.50C (lab.) at 140 MeV, 4.50-14.50 at 218 MeV. An optical model analysis of these strong structure angular distributions was done. Good fits of the data were obtained using the optical model search code GENOA with a full Woods-Saxon potential form. This yielded parameters subject to considerable ambiguities as it is known to occur for strongly absorbed particles. These ambiguities were explored in detail and it was found that both the real and the imaginary parts present some characteristics that have been found before for the real potential (as Igo relation for continous ambiguities and the fact that potentials with different diffusivities tend to have the same value at the strong absorption radii). It was found, among other results, that the real volume integral, the mean square radius, as well as the total reaction cross section (σsub(r)) cannot be determined unambiguously. A strong correlation was found between σsub(r) and the imaginary diffusivity. A systematic study of how the variation of the potential parameters affects the angular distribution is presented and some features of the diffraction structure of the angular distribution are discussed. (author)
Bystritsky, V. M.; Grozdanov, D. N.; Zontikov, A. O.; Kopach, Yu. N.; Rogov, Yu. N.; Ruskov, I. N.; Sadovsky, A. B.; Skoy, V. R.; Barmakov, Yu. N.; Bogolyubov, E. P.; Ryzhkov, V. I.; Yurkov, D. I.
2016-07-01
The work is devoted to measuring the angular distribution of 4.43-MeV γ-rays produced in inelastic scattering of 14.1-MeV neutrons by 12C nuclei. A portable ING-27 neutron generator (designed and fabricated at VNIIA, Moscow) with a built-in 64-pixel silicon α-detector was used as a source of tagged neutrons. The γ-rays of characteristic nuclear radiation from 12C were detected with a spectrometric system that consisted of 22 γ-detectors based on NaI(Tl) crystals arranged around the carbon target. The measured angular distribution of 4.43-MeV γ-rays is analyzed and compared with the results of other published experimental works.
A Survey of Beam Asymmetries in Semi-exclusive Electron Scattering on {sup 4}He and {sup 12}C
Energy Technology Data Exchange (ETDEWEB)
Dan Protopopescu
2002-12-01
A study of the polarized electron beam asymmetry in semi-exclusive (e,e{prime}p) reactions on {sup 4}He and {sup 12}C over a large kinematic range has been performed. The beam asymmetry A{prime}{sub LT} is related to the imaginary part of the longitudinal-transverse interference and therefore it vanishes in reactions proceeding through a channel with a single dominant mechanism. In quasifree nucleon knockout, the helicity asymmetry provides an unambiguous signature for the interference between direct knockout and rescattering amplitudes. The data were taken in April-May 1999 using polarized beams of energies between 2.2 and 4.4 GeV, with the CEBAF Large Acceptance Spectrometer (CLAS) detector located in Hall B at the Jefferson Laboratory, VA. The measured asymmetries compare well with the theoretical predictions.
Resonance strengths in the 14N(p,gamma)15O and 15N(p,alpha gamma)12C reactions
Marta, Michele; Bemmerer, Daniel; Beyer, Roland; Broggini, Carlo; Caciolli, Antonio; Erhard, Martin; Fülöp, Zsolt; Grosse, Eckart; Gyürky, György; Hannaske, Roland; Junghans, Arnd R; Menegazzo, Roberto; Nair, Chithra; Schwengner, Ronald; Szücs, Tamás; Vezzú, Simone; Wagner, Andreas; Yakorev, Dmitry
2010-01-01
The 14N(p,gamma)15O reaction is the slowest reaction of the carbon-nitrogen-oxygen cycle of hydrogen burning in stars. As a consequence, it determines the rate of the cycle. The 15N(p,alpha gamma)12C reaction is frequently used in inverse kinematics for hydrogen depth profiling in materials. The 14N(p,gamma)15O and 15N(p,alpha gamma)12C reactions have been studied simultaneously, using titanium nitride targets of natural isotopic composition and a proton beam. The strengths of the resonances at Ep = 1058 keV in 14N(p,gamma)15O and at Ep = 897 and 430 keV in 15N(p,alpha gamma)12C have been determined with improved precision, relative to the well-known resonance at Ep = 278 keV in 14N(p,gamma)15O. The new recommended values are \\omega\\gamma = 0.352$\\pm$0.018, 362$\\pm$20, and 22.0$\\pm$0.9\\,eV for their respective strengths. In addition, the branching ratios for the decay of the Ep = 1058 keV resonance in 14N(p,gamma)15O have been redetermined. The data reported here should facilitate future studies of off-resona...
Controlling electromagnetic scattering with wire metamaterial resonators
Filonov, Dmitry S.; Shalin, Alexander S.; Iorsh, Ivan; Belov, Pavel A.; Ginzburg, Pavel
2016-10-01
Manipulation of radiation is required for enabling a span of electromagnetic applications. Since properties of antennas and scatterers are very sensitive to a surrounding environment, macroscopic artificially created materials are good candidates for shaping their characteristics. In particular, metamaterials enable controlling both dispersion and density of electromagnetic states, available for scattering from an object. As the result, properly designed electromagnetic environment could govern waves' phenomena. Here electromagnetic properties of scattering dipoles, situated inside a wire medium (metamaterial) are analyzed both numerically and experimentally. Impact of the metamaterial geometry, dipole arrangement inside the medium, and frequency of the incident radiation on scattering phenomena was studied. It was shown that the resonance of the dipole hybridizes with Fabry-Perot modes of the metamaterial, giving rise to a complete reshaping of electromagnetic properties. Regimes of controlled scattering suppression and super-scattering were observed. Numerical analysis is in an agreement with experiments, performed at the GHz spectral range. The reported approach to scattering control with metamaterials could be directly mapped into optical and infrared spectral ranges by employing scalability properties of Maxwell's equations.
Resonant impurity scattering in the unconventional superconductors
Directory of Open Access Journals (Sweden)
Bang Yunkyu
2012-03-01
Full Text Available In this pedagogical review, I provide comparative studies of the impurity scattering effects on the two typical types of the unconventional superconductors: d-wave and ±s-wave superconductors. For the d-wave superconductor, the main effect of impurity scattering is the formation of the zero energy resonant state by the unitary scatters below Tc. Similarly, in the case of the ±s-wave superconductor, I show that impurity scattering of the unitary limit also forms a resonant bound state, however, not a zero energy but an off-centered bound state inside the superconducting (SC gap, which modifies the density of states (DOS of a fully opened gap to a V-shaped one mimicking the pure d-wave DOS. On the contrary, in the d-wave case, the zero energy bound state modifies the original V-shape DOS into a flat constant one near zero frequency. This contrasting behavior of the impurity effect can be useful to distinguish the gap symmetry of the newly discovered Fe-based superconductors. This contrasting behavior of two SC states with respect to the impurity scattering is demonstrated by numerical calculations of the density of states (DOS, NMR 1/T1 rate and Knight shift K(T.
Energy Technology Data Exchange (ETDEWEB)
Murata, Toru [AITEL Corp., Tokyo (Japan)
1998-03-01
The {sup 12}C({alpha},n){sup 15}O reaction and the {sup 13}C({alpha},n){sup 16}O reaction were analyzed with a resonance formula in the incident {alpha}-particle energy range of 1.0 to 16.0 MeV. With the obtained resonance parameters, branching ratios of the emitted neutrons to the several levels of the residual nucleus and their angular distributions were calculated to obtain the energy spectrum of emitted neutrons. Thick target neutron yield of carbon were also calculated and compared with the experimental data. (author)
Resonance scattering in quantum wells with nanocenters
Satanin, A M
2002-01-01
The study on the Fano resonances is carried out in the 2D systems and their contribution to the residual resistance is calculated. The quantum well, the states whereof interfere with the nanocenters, for example, with the delta-layer donor states or with the quantum points states, is considered as a model. It is shown, that the states, localized on the state centers, lead to the appearance of additional asymmetric peaks in the resistance dependence on the Fermi energy. It is also shown, that the finite radius nanocenters in the 2D electron layers may lead to origination of the Fano resonances in the scattering cross section
Resonances in photon-photon scattering
International Nuclear Information System (INIS)
A quantity called stickiness is introduced which should be largest for J not equal to 0 glueballs and can be measured in two photon scattering and radiative J/psi decay. An argument is reviewed suggesting that light J = 0 glueballs may have large couplings to two photons. The analysis of radiative decays of eta and eta' is reviewed and a plea made to desist from false claims that they are related to GAMMA(π0 → γγ) by SU(3) symmetry. It is shown that two photon studies can refute the difficult-to-refute hypothesis that xi(2220) or zeta(8320) are Higgs bosons. A gallery of rogue resonances and resonance candidates is presented which would usefully be studied in γγ scattering, including especially the low mass dipion. 34 references
Fano resonances in scattering: an alternative perspective
International Nuclear Information System (INIS)
The characteristic features of Fano resonances (also called Feshbach resonances in nuclear physics) are asymmetric line shapes, caused by the interaction between a discrete state and a continuum of states. In a previous paper it has been shown that the interference of the first and second order pole of the Green's function at an exceptional point, as well as the interference of the first order poles in the vicinity of the exceptional point, gives rise to asymmetric scattering cross section profiles. In the present paper we demonstrate that these line profiles are indeed well described by the Beutler-Fano formula, and thus are genuine Fano resonances. Also further away from the exceptional points excellent agreement can be found by introducing energy dependent Fano parameters
Mean-field study of $^{12}$C+$^{12}$C fusion
Chien, Le Hoang; Khoa, Dao T
2016-01-01
The nuclear mean-field potential arising from the $^{12}$C+$^{12}$C interaction at the low energies relevant for the astrophysical carbon burning process has been constructed within the double-folding model, using the realistic nuclear ground-state density of the $^{12}$C nucleus and the effective M3Y nucleon-nucleon (NN) interaction constructed from the G-matrix of the Paris (free) NN potential. To explore the nuclear medium effect, both the original density independent M3Y-Paris interaction and its density dependent CDM3Y6 version have been used in the folding model calculation of the $^{12}$C+$^{12}$C potential. The folded potentials at the different energies were used in the optical model description of the elastic $^{12}$C+$^{12}$C scattering at the energies around and below the Coulomb barrier, as well as in the barrier penetration model to estimate the fusion cross section and astrophysical $S$ factor of the $^{12}$C+$^{12}$C reactions at the low energies. The obtained results are in good agreement wit...
International Nuclear Information System (INIS)
The nuclear burning process proceeds from the conservation of the most abundant element hydrogen to helium, then from helium to carbon and oxygen, and then from these to heavier elements. Some of the key reactions for the carbon and oxygen burning stages of the nucleosynthesis are 12C+12C and 16O+16O leading to all possible final states. This paper contains the experimental measurements of 12C+12C and 16O+16O angular distributions performed at the cyclotron DC-60 in Astana, Kazakhstan. The extracted beam of 16O and 12C was accelerated up to two energies 1.75 and 1.5 MeV/n and then directed to an Al2O3 target of thickness 20 μg/cm2 and a carbon self-supporting target of thickness 17.4 μg/cm2. The angular distribution calculations were performed using both the phenomenological optical potential (SPI-GENOA) code and the double folding potential (FRESCO) code.
Interference scattering effects on intermediate resonance absorption at operating temperatures
International Nuclear Information System (INIS)
Resonance integrals may be accurately calculated using the intermediate resonance (IR) approximation. Results are summarized for the case of an absorber with given potential scattering cross sections and interference scattering parameter admixed with a non absorbing moderator of given cross section and located in a narrow resonance moderating medium. From the form of the IR solutions, it is possible to make some general observations about effects of interference scattering on resonance absorption. 2 figures
Spasova, K.; Lukyanov, V. K.; Kadrev, D. N.; Antonov, A. N.; Zemlyanaya, E. V.; Lukyanov, K. V.; Gaidarov, M. K.
2016-06-01
The elastic scattering cross-sections of 10,11Be on protons and 12C at energy E NN interactions, while the imaginary OP is estimated within the high energy approximation (HEA). The spin-orbit part of the OP is also included. The characteristics of the breakup processes of 11Be on different nuclear targets are also considered. The cross-sections of diffractive breakup and stripping reactions of 11Be on 9Be, 93Nb, 181Ta and 238U at energy E = 63 MeV/nucleon and the longitudinal momentum distributions of 10Be fragments produced in the breakup of 11Be on these nuclei are presented. The results are in a good agreement with the available experimental data, in particular the obtained widths of about 50 MeV/c are closed to the empirical ones.
Elastic and inelastic scattering studies for the systems 12C+28Si and 16O+/sup 28,29,30/Si
International Nuclear Information System (INIS)
Elastic and inelastic excitation functions for the systems 12C+ 28Si and 16O+/sup 28,29,30/Si have been measured at theta/sub c.m./ = 1800 from the Coulomb barrier up to E/sub c.m./ = 45 MeV (12C+28Si), E/sub c.m./ = 52 MeV (16O+28Si), and E/sub c.m./ = 32 MeV (16O+/sup 29,30/Si). Over the whole energy range they all exhibit pronounced and regular broad oscillations (0.50 were taken at five of the maxima and near a minimum of the excitation function for the system 16O+28Si. All angular distributions are oscillatory and exhibit a strong backward rise. The data are discussed in terms of a coherent superposition of a background and a resonant amplitude and in terms of the interference between the internal and barrier wave reflected by a deep optical potential
Fano resonances in scattering: an alternative perspective
Schwarz, Lukas; Cartarius, Holger; Wunner, Günter; Heiss, Walter Dieter; Main, Jörg
2015-08-01
In a previous paper it has been shown that the interference of the first and second order pole of the Green's function at an exceptional point, as well as the interference of the first order poles in the vicinity of the exceptional point, gives rise to asymmetric scattering cross section profiles. In the present paper we demonstrate that these line profiles are indeed well described by the Beutler-Fano formula, and thus are genuine Fano resonances. Also further away from the exceptional points excellent agreement can be found by introducing energy dependent Fano parameters.
Fano resonances in scattering: an alternative perspective
Schwarz, Lukas; Wunner, Günter; Heiss, Walter Dieter; Main, Jörg
2015-01-01
In a previous paper it has been shown that the interference of the first and second order pole of the Green's function at an exceptional point, as well as the interference of the first order poles in the vicinity of the exceptional point, gives rise to asymmetric scattering cross section profiles. In the present paper we demonstrate that these line profiles are indeed well described by the Beutler-Fano formula, and thus are genuine Fano resonances. Also further away from the exceptional points excellent agreement can be found by introducing energy dependent Fano parameters.
International Nuclear Information System (INIS)
The determination of polarization transfer observable for (rvec p, rvec p') reactions in intermediate energies provides a rich source of information on both the effective nucleon-nucleus interaction and the nuclear structure. The primary motivation for this work was to exploit the increased sensitivity predicted for these polarization transfer observable to the spin-dependent terms of the effective interaction used to describe nucleon-nucleus scattering at intermediate energies. To carry out this work the author has designed, built, and calibrated a polarimeter for the focal plane of the high resolution K600 Spectrometer. By using a low-energy beamline polarimeter and this Focal Plane Polarimeter, he has measured the normal-component spin observables DNN', P, and Ay at 200 MeV for the 1+, T = 0 (12.71 MeV) and T = 1 (15.11 MeV) states in 12C and for the 4-, T = 0 (17.79 and 19.80 MeV) and T = 1 (18.98 MeV) states in 16O. Measurements were made at five angles for the 12C transitions, at momentum transfers between 80 and 250 MeV/c, and at three angles for 16O, at momentum transfers of 225 to 400 MeV/c. The transitions chosen for this work have fairly well-determined nuclear structure and unnatural parity which maximizes the predicted sensitivity to the spin-dependent terms of the effective interaction. The results from this work will be used to address questions concerning the need for a relativistic interaction and how to incorporate corrections to the nuclear interaction due to the nuclear medium
The Use of the Scattering Phase Shift in Resonance Physics
Nowakowski, M
2004-01-01
The scattering phase shift encodes a good amount of physical information which can be used to study resonances from scattering data. Among others, it can be used to calculate the continuum density of states and the collision time in a resonant process. Whereas the first information can be employed to examine the evolution of unstable states directly from scattering data, the second one serves as a tool to detect resonances and their properties. We demonstrate both methods concentrating in the latter case on 'exotic' resonances in pi-pi and pi-K scattering.
Observation of resonant lattice modes by inelastic neutron scattering
DEFF Research Database (Denmark)
Bjerrum Møller, Hans; Mackintosh, A.R.
1965-01-01
Observation by inelastic neutron scattering of resonant lattice modes due to small concentration of W atoms in Cr host crystal; frequencies and lifetimes of phonons with frequencies near that of resonant mode are considerably affected by presence of defects.......Observation by inelastic neutron scattering of resonant lattice modes due to small concentration of W atoms in Cr host crystal; frequencies and lifetimes of phonons with frequencies near that of resonant mode are considerably affected by presence of defects....
X-ray resonant magnetic scattering ellipsometer
International Nuclear Information System (INIS)
It is very difficult to characterize the polarization of a synchrotron radiation source in the soft and/or intermediate x-ray energy region particularly from 1 to 2 keV. Conventional multilayer mirror or single-crystal polarimeters do not work over this energy region because their throughput (the reflectivities combined with the phase shift) becomes insignificant. In this paper, we present a new ellipsometer scheme that is able to fully characterize the polarization of synchrotron radiation sources in this energy region. It is based on the dichroic x-ray resonant ferromagnetic scattering that yields information on both the polarization of the x-ray and the material (element specific) dielectric-constant tensor [C.-C. Kao et al., Phys. Rev. B 50, 9599 (1994)] due to the interband ferromagnetic Kerr effect [B.R. Cooper, Phys. Rev. A 139, 1504 (1965)]. copyright 1996 American Institute of Physics
Scattering and Resonances in QCD_2
Frishman, Yitzhak; Frishman, Yitzhak; Karliner, Marek
2002-01-01
Extending previous works on the spectrum of QCD_2, we now investigate the 2D analogue of meson-baryon scattering. We use semi-classical methods, perturbing around classical soliton solutions. We start with the abelian case, corresponding to QED_2 and find that in this case the effective potential is reflectionless. We obtain an explicit expression for the forward phase shift. In the non-abelian case of QCD_2, the method yields a potential which depends on the momentum of the incoming particle. In this case there is both transmission and reflection. In both cases no resonances appear. As a byproduct, we derive the general conditions for a 2D quantum field theoretical action to yield a reflectionless effective potential when one expands in small fluctuations about the classical solution.
Fano resonance scattering in waveguide with an impedance boundary condition
Xiong, Lei; Aurégan, Yves
2015-01-01
Sound propagation in a waveguide lined with one section of locally reactive material is studied by resonance scattering approach. The objective is to understand the effects of mode coupling in the lined section on the transmission. It is shown that a transmission zero is present in the vicinity of a resonance peak when a numerically real resonance frequency of the open lined section (opened to infinities through the rigid parts of the waveguide) is crossed. The transmission zero and immediate resonance peak form a Fano resonance, it has been explained as an interaction between a resonance and the non-resonant background. The real resonance frequency and its corresponding trapped mode are formed by the interferences (couplings) between two neighbor modes with complex resonance frequencies. It is also linked to the avoided crossing of eigenvalues and the exceptional point. The scattering matrix is expressed in terms of a matrix $\\mathsf{H_{eff}}$ which describes approximately the complex resonances in the open ...
Mie scattering as a cascade of Fano resonances.
Rybin, Mikhail V; Samusev, Kirill B; Sinev, Ivan S; Semouchkin, George; Semouchkina, Elena; Kivshar, Yuri S; Limonov, Mikhail F
2013-12-01
We reveal that the resonant Mie scattering by high-index dielectric nanoparticles can be presented through cascades of Fano resonances. We employ the exact solution of Maxwell's equations and demonstrate that the Lorenz-Mie coefficients of the Mie problem can be expressed generically as infinite series of Fano functions as they describe interference between the background radiation originated from an incident wave and narrow-spectrum Mie scattering modes that lead to Fano resonances. PMID:24514559
Scatter-based magnetic resonance elastography
International Nuclear Information System (INIS)
Elasticity is a sensitive measure of the microstructural constitution of soft biological tissues and increasingly used in diagnostic imaging. Magnetic resonance elastography (MRE) uniquely allows in vivo measurement of the shear elasticity of brain tissue. However, the spatial resolution of MRE is inherently limited as the transformation of shear wave patterns into elasticity maps requires the solution of inverse problems. Therefore, an MRE method is introduced that avoids inversion and instead exploits shear wave scattering at elastic interfaces between anatomical regions of different shear compliance. This compliance-weighted imaging (CWI) method can be used to evaluate the mechanical consistency of cerebral lesions or to measure relative stiffness differences between anatomical subregions of the brain. It is demonstrated that CWI-MRE is sensitive enough to reveal significant elasticity variations within inner brain parenchyma: the caudate nucleus (head) was stiffer than the lentiform nucleus and the thalamus by factors of 1.3 ± 0.1 and 1.7 ± 0.2, respectively (P < 0.001). CWI-MRE provides a unique method for characterizing brain tissue by identifying local stiffness variations.
Resonant scattering of surface plasmon polaritons by dressed quantum dots
Energy Technology Data Exchange (ETDEWEB)
Huang, Danhong; Cardimona, Dave [Air Force Research Laboratory, Space Vehicles Directorate, Kirtland Air Force Base, New Mexico 87117 (United States); Easter, Michelle [Department of Mechanical Engineering, Stevens Institute of Technology, 1 Castle Point Terrace, Hoboken, New Jersey 07030 (United States); Gumbs, Godfrey [Department of Physics and Astronomy, Hunter College of the City University of New York, 695 Park Avenue, New York, New York 10065 (United States); Maradudin, A. A. [Department of Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lin, Shawn-Yu [Department of Electrical, Computer and Systems Engineering, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180 (United States); Zhang, Xiang [Department of Mechanical Engineering, 3112 Etcheverry Hall, University of California at Berkeley, Berkeley, California 94720 (United States)
2014-06-23
The resonant scattering of surface plasmon-polariton waves (SPP) by embedded semiconductor quantum dots above the dielectric/metal interface is explored in the strong-coupling regime. In contrast to non-resonant scattering by a localized dielectric surface defect, a strong resonant peak in the spectrum of the scattered field is predicted that is accompanied by two side valleys. The peak height depends nonlinearly on the amplitude of SPP waves, reflecting the feedback dynamics from a photon-dressed electron-hole plasma inside the quantum dots. This unique behavior in the scattered field peak strength is correlated with the occurrence of a resonant dip in the absorption spectrum of SPP waves due to the interband photon-dressing effect. Our result on the scattering of SPP waves may be experimentally observable and applied to spatially selective illumination and imaging of individual molecules.
Resonance elastic scattering and interference effects treatments in subgroup method
Energy Technology Data Exchange (ETDEWEB)
Li, Yun Zhao; He, Qing Ming; Cao, Liang Zhi; Wu, Hong Chun; Zu, Tie Jun [School of Nuclear Science and Technology, Xi' an Jiaotong University, Xi' an (China)
2016-04-15
Based on the resonance integral (RI) tables produced by the NJOY program, the conventional subgroup method usually ignores both the resonance elastic scattering and the resonance interference effects. In this paper, on one hand, to correct the resonance elastic scattering effect, RI tables are regenerated by using the Monte Carlo code, OpenMC, which employs the Doppler broadening rejection correction method for the resonance elastic scattering. On the other hand, a fast resonance interference factor method is proposed to efficiently handle the resonance interference effect. Encouraging conclusions have been indicated by the numerical results. (1) For a hot full power pressurized water reactor fuel pin-cell, an error of about +200 percent mille could be introduced by neglecting the resonance elastic scattering effect. By contrast, the approach employed in this paper can eliminate the error. (2) The fast resonance interference factor method possesses higher precision and higher efficiency than the conventional Bondarenko iteration method. Correspondingly, if the fast resonance interference factor method proposed in this paper is employed, the k{sub inf} can be improved by ∼100 percent mille with a speedup of about 4.56.
Low Frequency Scattering Resonance Wave in Strong Heterogeneity
Liu, Yinbin
2015-01-01
Multiple scattering of wave in strong heterogeneity can cause resonance-like wave phenomenon where signal exhibits low frequency, high intensity, and slowly propagating velocity. For example, long period event in volcanic seismology and surface plasmon wave and quantum Hall effect in wave-particle interactions. Collective behaviour in a many-body system is usually thought to be the source for generating the anomaly. However, the detail physical mechanism is not fully understood. Here I show by wave field modeling for microscopic bubble cloud model and 1D heterogeneity that the anomaly is related to low frequency scattering resonance happened in transient regime. This low frequency resonance is a kind of wave coherent scattering enhancement phenomenon in strongly-scattered small-scale heterogeneity. Its resonance frequency is inversely proportional to heterogeneous scale and contrast and will further shift toward lower frequency with random heterogeneous scale and velocity fluctuations. Low frequency scatterin...
Improved Fokker-Planck Equation for Resonance Line Scattering
Rybicki, G B
2006-01-01
A new Fokker-Planck equation is developed for treating resonance line scattering, especially relevant to the treatment of Lyman alpha in the early universe. It is a "corrected" form of the equation of Rybicki & Dell'Antonio that now obeys detailed balance, so that the approach to thermal equilibrium is properly described. The new equation takes into account the energy changes due to scattering off moving particles, the recoil term of Basko, and stimulated scattering. One result is a surprising unification of the equation for resonance line scattering and the Kompaneets equation. An improved energy exchange formula due to resonance line scattering is derived. This formula is compared to previous formulas of Madau, Meikson, & Rees (1997) and Chen & Miralda-Escud\\'e (2004).
Resonance scattering characteristics of double-layer spherical particles
Institute of Scientific and Technical Information of China (English)
Xuejin Dong; Mingxu Su; Xiaoshu Cai
2012-01-01
Based on the principle of ultrasonic resonance scattering,sound-scattering characteristics of double-layer spherical particles in water were numerically studied in this paper.By solving the equations of the scattering matrix,the scattering coefficient determined by the boundary conditions can be obtained,thus the expression for the sound-scattering function of a single double-layer spherical particle can be derived.To describe the resonance scattering characteristics of a single particle,the reduced scattering cross section and reduced extinction cross section curves were found through numerical calculation.Similarly,the numerically calculated sound attenuation coefficient curves were used to depict the resonance scattering characteristics of monodisperse and polydisperse particles.The results of numerical calculation showed that,for monodisperse particles,the strength of the resonance was mainly related to the particle size and the total number of particles; while for polydisperse particles,it was primarily affected by the particle size,the coverage of the particle size distribution and the particle concentration.
Scalar-Pseudoscalar scattering and pseudoscalar resonances
Albaladejo, M
2010-01-01
The interactions between the f_0(980) and a_0(980) scalar resonances and the lightest pseudoscalar mesons are studied. We first obtain the interacting kernels, without including any ad hoc free parameter, because the lightest scalar resonances are dynamically generated. These kernels are unitarized, giving the final amplitudes, which generate pseudoscalar resonances, associated with the K(1460), \\pi(1300), \\pi(1800), \\eta(1475) and X(1835). We also consider the exotic channels with I=3/2 and I^G=1^+ quantum numbers. The former could be also resonant in agreement with a previous prediction.
Guddala, Sriram; Ramakrishna, S Anantha
2016-01-01
A tri-layer metamaterial perfect absorber of light, consisting of (Al/ZnS/Al) films with the top aluminium layer patterned as an array of circular disk nanoantennas, is investigated for resonantly enhancing Raman scattering from C-60 fullerene molecules deposited on the metamaterial. The metamaterial is designed to have resonant bands due to plasmonic and electromagnetic resonances at the Raman pump frequency (725 nm) as well as Stokes emission bands. The Raman scattering from C60 on the metamaterial with resonantly matched bands is measured to be enhanced by an order of magnitude more than from C60 on metamaterials with off-resonant absorption bands peaked at 1090 nm. The Raman pump is significantly enhanced due to the resonance with a propagating surface plasmon band, while the highly impedance matched electromagnetic resonance is expected to couple out the Raman emission efficiently. The nature and hybridization of the plasmonic and electromagnetic resonances to form compound resonances are investigated by...
Optical Torque from Enhanced Scattering by Multipolar Plasmonic Resonance
Lee, Yoonkyung E; Jin, Dafei; Fang, Nicholas
2014-01-01
We present a theoretical study of the optical angular momentum transfer from a circularly polarized plane wave to thin metal nanoparticles of different rotational symmetries. While absorption has been regarded as the predominant mechanism of torque generation on the nanoscale, we demonstrate numerically how the contribution from scattering can be enhanced by using multipolar plasmon resonance. The multipolar modes in non-circular particles can convert the angular momentum carried by the scattered field, thereby producing scattering-dominant optical torque, while a circularly symmetric particle cannot. Our results show that the optical torque induced by resonant scattering can contribute to 80% of the total optical torque in gold particles. This scattering-dominant torque generation is extremely mode-specific, and deserves to be distinguished from the absorption-dominant mechanism. Our findings might have applications in optical manipulation on the nanoscale as well as new designs in plasmonics and metamateria...
Search for heavy resonances in vector boson scattering
Zhang, Guangyi; The ATLAS collaboration
2016-01-01
If the Higgs boson discovered at the LHC is not exactly the one predicted by the Standard Model the theory becomes strongly coupled at high energy and vector boson scattering violates unitarity in the TeV range. This can be regularised by the introduction of new heavy resonances. These resonances may also couple to quark pairs and can be searched for in their decay to vector or Higgs bosons. The ATLAS detector at the LHC is collecting data at 13 TeV since 2015. A search for new heavy resonances arising from WW scattering in vector boson fusion events using these data is presented. Interference effects between the new resonances and the Standard Model amplitude are fully taken into account. In addition searches for heavy resonances in the decay to a pair of bosons without tagging the initial state are shown.
Resonant Cyclotron Scattering and Comptonization in Neutron Star Magnetospheres
Lyutikov, M; Lyutikov, Maxim; Gavriil, Fotis P.
2006-01-01
Resonant cyclotron scattering of the surface radiation in the magnetospheres of neutron stars may considerably modify the emergent spectra and impede efforts to constraint neutron star properties. Resonant cyclotron scattering by a non-relativistic warm plasma in an inhomogeneous magnetic field has a number of unusual characteristics: (i) in the limit of high resonant optical depth, the cyclotron resonant layer is half opaque, in sharp contrast to the case of non-resonant scattering. (ii) The transmitted flux is on average Compton up-scattered by ~ $1+ 2 beta_T$, where $\\beta_T$ is the typical thermal velocity in units of the velocity of light; the reflected flux has on average the initial frequency. (iii) For both the transmitted and reflected fluxes the dispersion of intensity decreases with increasing optical depth. (iv) The emergent spectrum is appreciably non-Plankian while narrow spectral features produced at the surface may be erased. (v) Optical photons are less affected by resonant Comptonization tha...
Fano resonance scatterings in waveguides with impedance boundary conditions.
Xiong, Lei; Bi, Wenping; Aurégan, Yves
2016-02-01
The resonance scattering theory is used to study the sound propagation in a waveguide with a portion of its wall lined by a locally reacting material. The objective is to understand the effects of the mode coupling in the lined portion on the transmission. It is shown that a zero in the transmission is present when a real resonance frequency of the open system, i.e., the lined portion of the waveguide that is coupled to the two semi-infinite rigid ducts, is equal to the incident frequency. This transmission zero occurs as a Fano resonance-due to the excitation of a trapped mode in the open system. The trapped mode is formed by the interferences of two neighbored modes with complex resonance frequencies. It is also linked to the avoided crossing of eigenvalues of these two modes that occurs near an exceptional point (a subject that has attracted much attention in recent years in different physical domains). The real and complex resonance frequencies of the open system are determined by an equivalent eigenvalue problem of matrix Heff, which describes the eigenvalue problem defined in the finite lined portion (scattering region). With the aid of the eigenvalues and eigenfunctions of matrix Heff, the usual acoustic resonance scattering formula can be extended to describe the coupling effects between the scattering region and the rigid parts of the waveguide. PMID:26936558
Resonant response of electromagnetic scattering from ellipsoid
Gavriloaia, Mihai-Bogdan; Vizireanu, Constantin-Radu; Neamtu, Catalin; Preda, Radu; Achimescu, Emanuel; Halunga, Simona
2015-02-01
Modern radars must provide in a very short time: existence, mobility and shape of objects evolving in airspace. Evaluation of the object shapes through active research by using synthetic aperture radar is limited in time, resolution, and cost. A new way of processing non-stationary signals is presented in this article. Signals are obtained from the reflection of the electromagnetic field by objects with complex shape when they are irradiated with linear frequency modulated signals. The amplitude of reflected signal is variable on the radio-impulse duration depending on object shape, causing a certain electromagnetic signature. This phenomenon is caused by specific electromagnetic resonance. The reflected signal has maximum amplitude when the frequency of the incident wave is the same with the resonant frequency of the investigated object. The structure of an radar target can be decomposed into simple geometric shapes such as spheres, ellipsoids, prisms, and so on. Using resonant effect that ensures pattern recognition is exemplified by an object with an aerodynamic profile accepted in many component elements of the aircraft, namely - an ellipsoid. It is a geometric shape used extensively in aviation, because it has a very low aerodynamic resistance. The resonant response of ellipsoid is evaluated in a decade frequency band, but the pattern recognition of this shape is enough for an octave band. The resonant response is assessed for cross polarization of incident electromagnetic field, as well. As a result, the radio-impulse shape can be used in a data base for pattern recognition.
Ray, Hasi
2007-01-01
The best 3-channel projectile-inelastic [H(1s)+Ps(1s,2s,2p)] close-coupling approximation (CCA) is performed for positronium (Ps) and hydrogen (H) collision considering both the atoms in ground states at the incident channel. The s-wave elastic phase shifts and cross sections in the singlet and triplet channels and the total (or integrated) cross section are studied below inelastic threshold. Resonances in singlet channel using 2-channel and 3-channel projectile-inelastic CCAs confirm earlier prediction [1]. A resonance in triplet channel using 3-channel projectile-inelastic CCA is a new addition.
Resonance scattering of canonical elastic shells in absorbing fluid medium
Institute of Scientific and Technical Information of China (English)
ZHUO Linkai; FAN Jun; TANG Weilin
2008-01-01
Resonance scattering of elastic spherical shell and cylindrical shell while the sur-rounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable resul twould be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surround-ing fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little in fluence on the low-frequency resonance scattering induced by the filler inside the shell.
Resonance magnetic x-ray scattering study of erbium
DEFF Research Database (Denmark)
Sanyal, M.K.; Gibbs, D.; Bohr, J.;
1994-01-01
of this magnetic scattering and analyzed it using a simple model based on electric dipole and quadrupole transitions among atomic orbitals. The line shapes can be fitted to a magnetic structure combining both c-axis-modulated and basal-plane components. Below 18 K, we have observed unusual behavior......The magnetic phases of erbium have been studied by resonance x-ray-scattering techniques. When the incident x-ray energy is tuned near the L(III) absorption edge, large resonant enhancements of the magnetic scattering are observed above 18 K. We have measured the energy and polarization dependence...... of the magnetic scattering as a function of energy, whose origin is not understood....
Resonance propagation in heavy-ion scattering
Indian Academy of Sciences (India)
Bijoy Kundu; B K Jain
2001-06-01
The formalism developed earlier by us for the propagation of a resonance in the nuclear medium in proton–nucleus collisions has been modiﬁed to the case of vector boson production in heavy-ion collisions. The formalism includes coherently the contribution to the observed di-lepton production from the decay of a vector boson inside as well as outside the nuclear medium. The medium modiﬁcation of the boson is incorporated through an energy dependent optical potential. The calculated invariant mass distributions are presented for the -meson production using optical potentials estimated within the VDM and the resonance model. The shift in the invariant mass distribution is found to be small. To achieve the mass shift (of about 200 MeV towards lower mass) as indicated in the high energy heavy-ion collision experiments, an unusually strong optical potential of about -120 MeV is required. We also observe that, for not so heavy nuclear systems and/or for fast moving resonances, the shape, magnitude and peak position of the invariant mass distribution is substantially different if the contributions from the resonance decay inside and outside are summedup at the amplitude level (coherently) or at the cross section level (incoherently).
Self-Consistent Scattering Calculation of Resonant Tunneling Diode Characteristics
Sun, J P; Haddad, G. I.
1998-01-01
We perform a self-consistent calculation of resonant tunneling diode (RTD) I-V characteristics including optical phonon scattering. The self-consistency is obtained by solving the Schrödinger equation and Poisson’s equation iteratively with the Thomas-Fermi approximation used for the device contact regions. For evaluation of phonon-assisted current density, the optical phonon scattering in the quantum well is modeled using the optical model potential. Electron transverse momentum is also inco...
New Physics / Resonances in Vector Boson Scattering at the LHC
Reuter, J; Ohl, T; Sekulla, M
2016-01-01
Vector boson scattering is (together with the production of multiple electroweak gauge bosons) the key process in the current run 2 of LHC to probe the microscopic nature of electroweak symmetry breaking. Deviations from the Standard Model are generically parameterized by higher-dimensional operators, however, there is a subtle issue of perturbative unitarity for such approaches for the process above. We discuss a parameter-free unitarization prescription to get physically meaningful predictions. In the second part, we construct simplified models for generic new resonances that can appear in vector boson scattering, with a special focus on the technicalities of tensor resonances.
Resonant Raman Scattering from Silicon Nanoparticles Enhanced by Magnetic Response
Dmitriev, Pavel A; Milichko, Valentin A; Makarov, Sergey V; Mukhin, Ivan S; Samusev, Anton K; Krasnok, Alexander E; Belov, Pavel A; Kivshar, Yuri S
2016-01-01
Enhancement of optical response with high-index dielectric nanoparticles is attributed to the excitation of their Mie-type magnetic and electric resonances. Here we study Raman scattering from crystalline silicon nanoparticles and reveal that magnetic dipole modes have much stronger effect on the scattering than electric modes of the same order. We demonstrate experimentally a 140-fold enhancement of Raman signal from individual silicon spherical nanoparticles at the magnetic dipole resonance. Our results confirm the importance of the optically-induced magnetic response of subwavelength dielectric nanoparticles for enhancing light-matter interactions.
Fano Resonance Enhanced Nonreciprocal Absorption and Scattering of Light
Directory of Open Access Journals (Sweden)
Ben Hopkins
2015-06-01
Full Text Available We reveal that asymmetric plasmonic nanostructures can exhibit significantly different absorption and scattering properties for light that propagates in opposite directions, despite the conservation of total extinction. We analytically demonstrate that this is a consequence of nonorthogonality of eigenmodes of the system. This results in the necessity for modal interference with potential enhancement via Fano resonances. Based on our theory, we propose a stacked nanocross design whose optical response exhibits an abrupt change between absorption and scattering cross-sections for plane waves propagating in opposite directions. This work thereby proposes the use of Fano resonances to employ nanostructures for measuring and distinguishing optical signals coming from opposite directions.
Resonant Raman scattering from silicon nanoparticles enhanced by magnetic response.
Dmitriev, Pavel A; Baranov, Denis G; Milichko, Valentin A; Makarov, Sergey V; Mukhin, Ivan S; Samusev, Anton K; Krasnok, Alexander E; Belov, Pavel A; Kivshar, Yuri S
2016-05-01
Enhancement of optical response with high-index dielectric nanoparticles is attributed to the excitation of their Mie-type magnetic and electric resonances. Here we study Raman scattering from crystalline silicon nanoparticles and reveal that magnetic dipole modes have a much stronger effect on the scattering than electric modes of the same order. We demonstrate experimentally a 140-fold enhancement of the Raman signal from individual silicon spherical nanoparticles at the magnetic dipole resonance. Our results confirm the importance of the optically-induced magnetic response of subwavelength dielectric nanoparticles for enhancing light-matter interactions. PMID:27113352
Resonances in low-energy positron-alkali scattering
Horbatsch, M.; Ward, S. J.; Mceachran, R. P.; Stauffer, A. D.
1990-01-01
Close-coupling calculations were performed with up to five target states at energies in the excitation threshold region for positron scattering from Li, Na and K. Resonances were discovered in the L = 0, 1 and 2 channels in the vicinity of the atomic excitation thresholds. The widths of these resonances vary between 0.2 and 130 MeV. Evidence was found for the existence of positron-alkali bound states in all cases.
Resonance eigenfunctions in chaotic scattering systems
Indian Academy of Sciences (India)
Martin Sieber
2009-09-01
We study the semiclassical structure of resonance eigenstates of open chaotic systems. We obtain semiclassical estimates for the weight of these states on different regions in phase space. These results imply that the long-lived right (left) eigenstates of the non-unitary propagator are concentrated in the semiclassical limit ħ → 0 on the backward (forward) trapped set of the classical dynamics. On this support the eigenstates display a self-similar behaviour which depends on the limiting decay rate.
Resonantly enhanced Bragg-scattering spectroscopy of an atomic transition
Yang, Xudong; Qiao, Cuifang; Li, Chuanliang; Chen, Fenghua
2016-07-01
A novel resonantly enhanced Bragg-scattering (REBS) spectroscopy from a population difference grating (PDG) is reported. The PDG is formed by a standing-wave (SW) pump field, which periodically modulates the space population distributions of two levels in the 87Rb D1 line. Then, a probe beam, having identical frequency and orthogonal polarization with the SW pump field, is Bragg-scattered by the PDG. The research achievement shows that the Bragg-scattered light is strongest at an atomic transition, and forms an REBS spectrum with a high signal-to-noise ratio and sub-natural linewidth. The observed REBS can be applied in precise frequency measurements.
Chaotic scattering in the regime of weakly overlapping resonances.
Dietz, B; Friedrich, T; Harney, H L; Miski-Oglu, M; Richter, A; Schäfer, F; Weidenmüller, H A
2008-11-01
We measure the transmission and reflection amplitudes of microwaves in a resonator coupled to two antennas at room temperature in the regime of weakly overlapping resonances and in a frequency range of 3-16GHz . Below 10.1GHz the resonator simulates a chaotic quantum system. The distribution of the elements of the scattering matrix S is not Gaussian. The Fourier coefficients of S are used for a best fit of the autocorrelation function of S to a theoretical expression based on random-matrix theory. We find very good agreement below but not above 10.1GHz .
Raman Scattering at Resonant or Near-Resonant Conditions: A Generalized Short-Time Approximation
Institute of Scientific and Technical Information of China (English)
Abdelsalam Mohammed; Yu-Ping Sun; Quan Miao; Hans (A)gren; Faris Gel'mukhanov
2012-01-01
We investigate the dynamics of resonant Raman scattering in the course of the frequency detuning.The dephasing in the time domain makes the scattering fast when the photon energy is tuned from the absorption resonance.This makes frequency detuning to act as a camera shutter with a regulated scattering duration and provides a practical tool of controlling the scattering time in ordinary stationary measurements.The theory is applied to resonant Raman spectra of a couple of few-mode model systems and to trans-1,3,5-hexatriene and guanine-cytosine (G-C) Watson-Crick base pairs (DNA) molecules.Besides some particular physical effects,the regime of fast scattering leads to a simplification of the spectrum as well as to the scattering theory itself.Strong overtones appear in the Raman spectra when the photon frequency is tuned in the resonant region,while in the mode of fast scattering,the overtones are gradually quenched when the photon frequency is tuned more than one vibrational quantum below the first absorption resonance.The detuning from the resonant region thus leads to a strong purification of the Raman spectrum from the contamination by higher overtones and soft modes and purifies the spectrum also in terms of avoidance of dissociation and interfering fluorescence decay of the resonant state.This makes frequency detuning a very useful practical tool in the analysis of the resonant Raman spectra of complex systems and considerably improves the prospects for using the Raman effect for detection of foreign substances at ultra-low concentrations.
Off-the-energy-shell pp scattering in the exclusive proton knockout 12C(p,2p) reaction at 392 MeV
Sumi, T T
2008-01-01
The triple differential cross section (TDX) for the 12C(p,2p) proton knockout reaction from the 1p3/2 single-particle state measured at 392 MeV is investigated by nonrelativistic distorted wave impulse approximation (DWIA) with accurate treatment of the kinematics of the colliding two protons and effects of in-medium modification to the matrix elements of the proton-proton (pp) effective interaction. Some simplifying approximations made in previous studies with DWIA are examined. The off-the-energy-shell matrix elements of the pp effective interaction are shown to play an essential role in describing the asymmetric two peaks of the measured TDX corresponding to the kinematics in which the momentum transfer is fixed.
D Pi scattering and D meson resonances from lattice QCD
Mohler, Daniel; Woloshyn, R M
2012-01-01
The masses and widths of the broad scalar D_0^*(2400) and the axial D_1(2430) charmed-light resonances are extracted by simulating the corresponding D Pi and D* Pi scattering on the lattice. The resonance parameters are obtained using a Breit-Wigner fit of the elastic phase shifts. The resulting D_0^*(2400) mass is 351+/-21 MeV above the spin-average 1/4(m_D+3m_{D*}), in agreement with the experimental value of 347+/-29 MeV above. The resulting D_0^* to D Pi coupling g^{lat}=2.55+/-0.21 GeV is close to the experimental value g^{exp}<=1.92+/-0.14 GeV, where g parametrizes the width $\\Gamma\\equiv g^2p^*/s$. The resonance parameters for the broad D_1(2430) are also found close to the experimental values; these are obtained by appealing to the heavy quark limit, where the neighboring resonance D_1(2420) is narrow. The calculated I=1/2 scattering lengths are a_0=0.81+/-0.14 fm for D Pi and a_0=0.81+/-0.17 fm for D* Pi scattering. The simulation of the scattering in these channels incorporates quark-antiquark as...
E791 Collaboration; Leksanov, A.; Alster, J.; Asryan, G.; Averichev, Y.; Barton, D; Baturin, V.; Bukhtoyarova, N.; Carroll, A.; Heppelmann, S.; Kawabata, T.; Makdisi, Y.; Malki, A.; Minina, E.; Navon, I.
2000-01-01
We present a new measurement of the energy dependence of nuclear transparency from AGS experiment E850, performed using the EVA solenoidal spectrometer, upgraded since 1995. Using a secondary beam from the AGS accelerator, we simultaneously measured $pp$ elastic scattering from hydrogen and $(p,2p)$ quasi-elastic scattering in carbon at incoming momenta of 5.9, 8.0, 9.0, 11.7 and 14.4 GeV/c. This incident momentum range corresponds to a $Q^{2}$ region between 4.8 and 12.7 (GeV/c)$^{2}$. The d...
Resonance structure in elastic scattering of electrons from atomic hydrogen
Energy Technology Data Exchange (ETDEWEB)
Warner, C.D.; King, G.C.; Hammond, P.; Slevin, J.
1986-10-28
High-energy-resolution spectra of electrons scattered elastically from atomic hydrogen have been obtained for incident electron energies of 9.2-10.4 eV and at angles of 33/sup 0/, 54/sup 0/, 70/sup 0/ and 90/sup 0/. The energy spread of the incident electron beam is estimated to be typically 25 meV FWHM. In addition to the /sup 1/S and /sup 3/P resonances which have been reported in earlier studies, a /sup 1/D resonance can be clearly seen and there is some evidence of a resonance state at a higher energy, probably corresponding to a /sup 1/S resonance state. The energies and resonance widths of all these features have been determined.
Resonance structure in elastic scattering of electrons from atomic hydrogen
International Nuclear Information System (INIS)
High-energy-resolution spectra of electrons scattered elastically from atomic hydrogen have been obtained for incident electron energies of 9.2-10.4 eV and at angles of 330, 540, 700 and 900. The energy spread of the incident electron beam is estimated to be typically 25 meV FWHM. In addition to the 1S and 3P resonances which have been reported in earlier studies, a 1D resonance can be clearly seen and there is some evidence of a resonance state at a higher energy, probably corresponding to a 1S resonance state. The energies and resonance widths of all these features have been determined. (author)
Yao, Xiaojun; Müller, Berndt
2016-01-01
We study the dynamical screening effect in the QED plasma on the $\\alpha$-$\\alpha$ scattering at the $^8$Be resonance. Dynamical screening leads to an imaginary part of the potential which results in a thermal width for the resonance and dominates over the previously considered static screening effect. As a result, both the resonance energy and width increase with the plasma temperature. Furthermore, dynamical screening can have a huge impact on the $\\alpha$-$\\alpha$ thermal nuclear scattering rate. For example, when the temperature is around $10$ keV, the rate is suppressed by a factor of about $900$. We expect similar thermal suppressions of nuclear reaction rates to occur in nuclear reactions dominated by an above threshold resonance with a thermal energy. Dynamical screening effects on nuclear reactions can be relevant to cosmology and astrophysics.
Leksanov, A.; Alster, J.; Asryan, G.; Averichev, Y.; Barton, D.; Baturin, V.; Bukhtojarova, N.; Carroll, A.; Schetkovsky, A.; Heppelmann, S.; Kawabata, T.; Malki, A.; Makdisi, Y.; Minina, E.; Navon, I.; Nicholson, H.; Ogawa, A.; Panebratsev, Y.; Piasetzky, E.; Shimanskiy, S.; Tang, A.; Watson, J. W.; Yoshida, H.; Zhalov, D.
2000-12-01
We present a new measurement of the energy dependence of nuclear transparency from AGS experiment E850, performed using the EVA solenoidal spectrometer, upgraded since 1995. Using a secondary beam from the AGS accelerator, we simultaneously measured pp elastic scattering from hydrogen and (p,2p) quasi-elastic scattering in carbon at incoming momenta of 5.9, 8.0, 9.0, 11.7 and 14.4 GeV/c. This incident momentum range corresponds to a Q2 region between 4.8 and 12.7 (GeV/c)2. The detector allowed us to do a complete kinematic analysis for the center-of-mass polar angles in the range 85°-90°. We report on the measured variation of the nuclear transparency with energy and compare the new results with previous measurements.
Resonant proton scattering of $^{22}$Mg and $^{21}$Na
Di julio, D D; Jansson, K; Rudolph, D; Fynbo, H O U; Nilsson, T; Perea martinez, A
In our letter-of-intent, INTC-I-051, we discussed the physics case for scattering and transfer reactions involving light nuclei in the break-out region of the rp-process. The Committee found the physics case compelling and supported the letter-of-intent under the premise that beams of proper quality were developed and that an adequate detector set-up was presented. As these two requirements have been met recently we now propose to study resonant proton scattering of $^{22}$Mg to identify the states at 1.733 MeV and 2.575 MeV in $^{23}$Al that have been reported from the $^{24}$Mg($^{7}$Li,$^{8}$He)$\\,^{23}\\!$Al reaction but that remained unobserved in the only resonant proton scattering experiment performed with $^{22}$Mg so far. In particular we should be able to investigate the character of the proton emission of the 2.575 MeV state which may also have a significant inelastic branch. We also propose to perform resonant proton scattering on $^{21}$Na above $\\alpha$-particle threshold with $^{18}$Ne to study ...
DEFF Research Database (Denmark)
Birkedal, Dan; Shah, Jagdeep; Shchegrov, Andrei V.;
2000-01-01
Resonant Rayleigh scattering from quantum well excitons is investigated using ultrafast spectral interferometry. We isolate the coherent Rayleigh scattering from incoherent luminescence in a single speckle. Averaging the resonant Rayleigh intensity over several speckles allows us to identify...
Resonant magnetic scattering of polarized soft x rays
Energy Technology Data Exchange (ETDEWEB)
Sacchi, M. [Centre Universitaire Paris-Sud, Orsay (France); Hague, C.F. [Universite Pierre et Marie Curie, Paris (France); Gullikson, E.M.; Underwood, J. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)
1997-04-01
Magnetic effects on X-ray scattering (Bragg diffraction, specular reflectivity or diffuse scattering) are a well known phenomenon, and they also represent a powerful tool for investigating magnetic materials since it was shown that they are strongly enhanced when the photon energy is tuned across an absorption edge (resonant process). The resonant enhancement of the magnetic scattering has mainly been investigated at high photon energies, in order to match the Bragg law for the typical lattice spacings of crystals. In the soft X-ray range, even larger effects are expected, working for instance at the 2p edges of transition metals of the first row or at the 3d edges of rare earths (300-1500 eV), but the corresponding long wavelengths prevent the use of single crystals. Two approaches have been recently adopted in this energy range: (i) the study of the Bragg diffraction from artificial structures of appropriate 2d spacing; (ii) the analysis of the specular reflectivity, which contains analogous information but has no constraints related to the lattice spacing. Both approaches have their own specific advantages: for instance, working under Bragg conditions provides information about the (magnetic) periodicity in ordered structures, while resonant reflectivity can easily be related to electronic properties and absorption spectra. An important aspect common to all the resonant X-ray scattering techniques is the element selectivity inherent to the fact of working at a specific absorption edge: under these conditions, X-ray scattering becomes in fact a spectroscopy. Results are presented for films of iron and cobalt.
Resonance electronic Raman scattering in rare earth crystals
Energy Technology Data Exchange (ETDEWEB)
Williams, G.M.
1988-11-10
The intensities of Raman scattering transitions between electronic energy levels of trivalent rare earth ions doped into transparent crystals were measured and compared to theory. A particle emphasis was placed on the examination of the effect of intermediate state resonances on the Raman scattering intensities. Two specific systems were studied: Ce/sup 3 +/(4f/sup 1/) in single crystals of LuPO/sub 4/ and Er/sup 3 +/(4f/sup 11/) in single crystals of ErPO/sub 4/. 134 refs., 92 figs., 33 tabs.
Resonance electronic Raman scattering in rare earth crystals
International Nuclear Information System (INIS)
The intensities of Raman scattering transitions between electronic energy levels of trivalent rare earth ions doped into transparent crystals were measured and compared to theory. A particle emphasis was placed on the examination of the effect of intermediate state resonances on the Raman scattering intensities. Two specific systems were studied: Ce3+(4f1) in single crystals of LuPO4 and Er3+(4f11) in single crystals of ErPO4. 134 refs., 92 figs., 33 tabs
Far-field superresolution by imaging of resonance scattering
Schuster, Gerard T.
2014-10-31
We show that superresolution imaging in the far-field region of the sources and receivers is theoretically and practically possible if migration of resonant multiples is employed. A resonant multiple is one that bounces back and forth between two scattering points; it can also be the multiple between two smoothly varying interfaces as long as the reflection wave paths partially overlap and reflect from the same Fresnel zone. For a source with frequency f, compared to a one-way trip, N round trips in propagating between two scatterers increase the effective frequency by 2N × f and decrease the effective wavelength by λ/(2N). Thus, multiples can, in principle, be used as high-frequency probes to estimate detailed properties of layers. Tests with both synthetic and field data validate this claim. Improved resolution by multiple imaging is not only feasible for crustal reflections, but might be applicable to mantle and core reverberations recorded by earthquake seismologists.
Energy Technology Data Exchange (ETDEWEB)
Takeuchi, Koh [National Institute of Advanced Industrial Science and Technology (AIST), Biomedicinal Information Research Center (BIRC) (Japan); Frueh, Dominique P.; Sun, Zhen-Yu J.; Hiller, Sebastian; Wagner, Gerhard, E-mail: gerhard_wagner@hms.harvard.ed [Harvard Medical School, Department of Biological Chemistry and Molecular Pharmacology (United States)
2010-05-15
We present a {sup 13}C direct detection CACA-TOCSY experiment for samples with alternate {sup 13}C-{sup 12}C labeling. It provides inter-residue correlations between {sup 13}C{sup {alpha}} resonances of residue i and adjacent C{sup {alpha}s} at positions i - 1 and i + 1. Furthermore, longer mixing times yield correlations to C{sup {alpha}} nuclei separated by more than one residue. The experiment also provides C{sup {alpha}}-to-side chain correlations, some amino acid type identifications and estimates for {psi} dihedral angles. The power of the experiment derives from the alternate {sup 13}C-{sup 12}C labeling with [1,3-{sup 13}C] glycerol or [2-{sup 13}C] glycerol, which allows utilizing the small scalar {sup 3}J{sub CC} couplings that are masked by strong {sup 1}J{sub CC} couplings in uniformly {sup 13}C labeled samples.
Resonant scattering and diffraction beamline P09 at PETRA III
Strempfer, J.; Francoual, S.; Reuther, D.; Shukla, D. K.; Skaugen, A.; Schulte-Schrepping, H.; Kracht, T.; Franz, H.
2013-01-01
The resonant scattering and diffraction beamline P09 at PETRA III is designed for X-ray experiments requiring small beams, energy tunability, variable polarization and high photon flux. It is highly flexible in terms of beam size and offers full higher harmonic suppression. A state of the art double phase retarder setup provides variable linear or circular polarization. A high precision Psi-diffractometer and a heavy load diffractometer in horizontal Psi-geometry allow the accommodation of a ...
Resonance scattering of radio waves in the acoustically disturbed ionosphere
International Nuclear Information System (INIS)
It is known that acoustic waves are excited in the atmosphere for a variety of reasons, including seismic oscillations of the earth's surface as a result of earthquakes, volcanic eruptions, explosions, and in the operation of other powerful sources of natural or artificial origin. When sound waves are sufficiently intense, they can create disturbances in the electron density at ionospheric heights. In this paper, we consider the properties of radio wave scattering off such disturbances created by infrasound waves, i.e., we consider Mandel'shtam-Brillouin scattering in the ionosphere. The authors discuss the possibility of a radiophysical enhancement of the effect connected with the phenomenon of resonance scattering of the radiowaves off the disturbances created in the medium by the acoustic wave
Compositeness of the Delta(1232) resonance in pi N scattering
Sekihara, Takayasu; Yamagata-Sekihara, Junko; Yasui, Shigehiro
2015-01-01
We evaluate the $\\pi N$ compositeness of the $\\Delta (1232)$ resonance so as to clarify the internal structure of $\\Delta (1232)$ in terms of the $\\pi N$ component. Here the compositeness is defined as contributions from two-body wave functions to the normalization of the total wave function and is extracted from the $\\pi N$ scattering amplitude. In this study we employ the chiral unitary approach with the interaction up to the next-to-leading order plus a bare $\\Delta$ term in chiral perturbation theory and describe $\\Delta (1232)$ in an elastic $\\pi N$ scattering. Fitting the $\\pi N$ scattering amplitude to the solution of the partial wave analysis, we obtain a large real part of the $\\pi N$ compositeness for $\\Delta (1232)$ comparable to unity and non-negligible imaginary part as well, with which we reconfirm the result in the previous study on the $\\pi N$ compositeness for $\\Delta (1232)$.
Institute of Scientific and Technical Information of China (English)
HU Xiao-li; LIU Sa; LIU Shao-pu; LIU Zhong-fang; SONG Yan-qi
2011-01-01
In a pH=0.65-1.5 NaAc-HCI medium, methylene blue(MB) reacts with 12-tungstophosphoric acid (TPA) by virtue of electrostatic attraction and hydrophobic force to form a 3:2 ion-association complex. As a result,the intensities of resonance Rayleigh scattering(RRS), second-order scattering(SOS) and frequency doubling scattering(FDS) are enhanced greatly. The maximum scattering wavelengths of RRS, SOS and FDS are located at 316, 647 and 311 nm. The increments of scattering intensity(ΔI) are directly proportional to the concentration of MB in a certain range. The methods exhibited high sensitivity, and the detection limits(3σ) for MB are 2.3 ng/mL(RRS method),5.6 ng/mL(SOS method) and 6.4 ng/mL(FDS method), respectively. The effects of coexisting substances have been examined, and the results indicate that the methods have good selectivity. Based on the above researches, a new spectral method for the determination of trace amounts of MB has been developed. It can be applied to the determination of MB in human serum, and the recoveries are 97.5％-105.0％. The results are in good agreement with those obtained by the pharmacopoeia method. In this work, the optimum conditions of the reaction and the influencing factors were investigated. In addition, the reaction mechanism and the reasons of the enhancement of resonance light scattering were discussed.
International Nuclear Information System (INIS)
This research thesis reports the study of the mechanism of emission of alpha particles in the 11B (p, 3 α) reaction with respect to the effects of spins and parities of the various resonances met between 150 keV and 4 MeV. From an experimental point of view, the reaction has been studied by two methods: the detection of alpha particles by a semiconductor-based counter located at a given angle with respect to the beam direction and study of continuous spectra of alpha particles with respect to projectile energies, and recording, for a given resonance, of alpha-alpha coincidences by using the multi-parametric technique with two semiconductor-based sensors with a varying relative angular position. After a discussion of the main characteristics of resonance and of the mechanism of emission of alpha particles, the author first reports the theoretical study of a reaction producing three particles in the final state, and then reports the theoretical calculation of direct alpha spectrum shapes in the case of the 11B (p, 3 α) reaction (statistic hypothesis, hypothesis of interaction with two particles in the final state). The next part reports the experimental study of the 11B (p, 3 α) reaction
Resonant depolarized dynamic light scattering of silver nanoplatelets
Energy Technology Data Exchange (ETDEWEB)
Zimbone, M., E-mail: massimo.zimbone@ct.infn.it [CNR-IMM (Italy); Messina, E. [IPCF-CNR Istituto per i Processi Chimico-Fisici (Italy); Compagnini, G.; Fragalà, M. E. [Dipartimento di Scienze Chimiche (Italy); Calcagno, L. [Dipartimento di Fisica ed Astronomia (Italy)
2015-10-15
Polarized and depolarized dynamic light scattering (DDLS) methodology was carried out on silver nanoplatelets showing strong plasmon-enhanced scattering. The hydrodynamic properties of the nanoparticles were determined by measuring the translation diffusion coefficient for “out resonant” condition and the rotational diffusion coefficient for “in resonant” condition. The results have been interpreted by applying an oblate ellipsoidal model, which allows a direct evaluation of nanoplatelets’ size and shape in agreement with scanning electron microscopy. The characterised nanoplatelets reveal a transversal size of 20 nm and a longitudinal length in the range 65–92 nm. Our investigation shows that DDLS in resonant condition is a simple and powerful technique to determine the size and shape of plasmonic nanoparticles and it can be successfully applied to characterise the dynamics of metallic nanoplatelets.
On the resonance structure in nucleon-nucleon scattering
Kloet, W. M.; Tjon, J. A.
1981-10-01
A possible explanation of resonance-like structure in 1D 2 and 3F 3 proton-proton phase parameters at medium energy is suggested by the analysis of an exactly soluble coupled channel model. Looping in the Argand plot is mainly due to the nucleon-delta branch cut. This effect is already present in the NΔ box diagram, but is modified by higher order multiple scattering. Poles occur close to the NΔ branch point and originate from left-hand singularities in the unphysical sheet.
Resonance Region Structure Functions and Parity Violating Deep Inelastic Scattering
Carlson, Carl E.; Rislow, Benjamin C.
2012-01-01
The primary motive of parity violating deep inelastic scattering experiments has been to test the standard model, particularly the axial couplings to the quarks, in the scaling region. The measurements can also test for the validity of models for the off-diagonal structure functions $F_{1,2,3}^{\\gamma Z}(x,Q^2)$ in the resonance region. The off-diagonal structure functions are important for the accurate calculation of the $\\gamma Z$-box correction to the weak charge of the proton. Currently, ...
Resonant electronic Raman scattering: A BCS-like system
Rodrigues, Leonarde N.; Arantes, A.; Schüller, C.; Bell, M. J. V.; Anjos, V.
2016-05-01
In this paper we investigate the resonant intersubband Raman scattering of two-dimensional electron systems in GaAs-AlGaAs single quantum wells. Self-consistent calculations of the polarized and depolarized Raman cross sections show that the appearance of excitations at the unrenormalized single-particle energy are related to three factors: the extreme resonance regime, the existence of degeneracy in intersubband excitations of the electron gas, and, finally, degeneracy in the interactions between pairs of excitations. It is demonstrated that the physics that governs the problem is similar to the one that gives rise to the formation of the superconducting state in the BCS theory of normal metals. Comparison between experiment and theory shows an excellent agreement.
Measurements and applications of neutron multiple scattering in resonance region
International Nuclear Information System (INIS)
Capture yield of neutrons impinging on a thick material is complicated due to self-shielding and multiple scattering, especially in the resonance region. When the incident neutron energy is equal to a resonance energy of the material, capture probability of the neutron increases with sample thickness and reaches a saturation value P sub(CO). There is a simple relation between P sub(CO) and GAMMA sub(n)/GAMMA and the recoil energy by the Monte-Carlo calculation. To examine validity of the relation, P sub(CO) was measured for 19 resonances in 12 nuclides with thick samples, using a JAERI linac time-of-flight spectrometer with Moxon-Rae type gamma ray detector and transmission type neutron flux monitor. Results of the measurements confirmed the validity. With this relation, the GAMMA sub(n)/GAMMA or GAMMA sub(γ)/GAMMA value can be obtained from the measured P sub(CO), and also the level spins be determined by combining the transmission data. Because of the definition of P sub(CO), determination of the resonance parameters is not sensitive to the sample thickness as far as it is sufficiently thick. (auth.)
Institute of Scientific and Technical Information of China (English)
JIANG,Zhi-Liang(蒋治良); PENG,Zhong-Li(彭忠利); LIU,Shao-Pu(刘绍璞)
2002-01-01
A new resonance scattering spectral (RSS) method for the determination of human serum album (HSA) has been proposed with the resonance scattering enhanced reagent of K3[Fe(CN)6]. In the medium of HCl (2,0× 10-3 mol/L), HSA may combine with [Fe(CN)6]3- by intermolecular forces (mainly by electrostatic force) to form {[Fe (CN)6]3n-HSAm+ }k nanoparticle of the ion-association complexes of HSAm+-[Fe(CN)6]3n-. There is a strongest resonance scattering intensity at 351 nm, owing to the existence of the resonance scattering of the nanoparticle, [Fe(CN)6]3- molecular absorption and the non-distribution of the emission intensity of Xe lamp in the range of 200-1000 nm. In addition, two resonance scattering peaks at 470 and 700 nm were observed. Tne HSA concentration in the range of 0-12 μg/mL is lhear to the resonance scattering intensity at 351 mn. The determination limit of this method is 0.1 μg/mL HSA, about ten-fold lower than that of Coomassie brilliant blue protein assay. This method has been used for the determination of HSA in human serum ami synthetic samples with satisfactory results. The mechanism of enhanced resonance scattering light, the TEM of the particle, the concepts of quasi-elastic absorption and tm-elastic absorption were also discussed.
12C+12C reactions at astrophysical energies: Tests of targets behaviour under beam bombardment
International Nuclear Information System (INIS)
12C(12C,α)20Ne and 12C(12C,p)23Na are the most important reactions during the carbon burning phase in stars. Direct measurements at the relevant astrophysical energy (E=1.5±0.3MeV) are very challenging because of the extremely small cross sections involved and of the high beam-induced background originating from impurities in the targets. In addition, persistent resonant structures at low energies are not well understood and make the extrapolation of the cross section from high energy data very uncertain. As a preliminary step towards the measurements of the 12C(12C,α)20Ne and 12C(12C,p)23Na reactions we intend to investigate the behaviour of targets under beam bombardment, specifically the quantitative measurement of hydrogen and deuterium content of highly pure stable carbon targets in relation to target temperature. Experiments are taking place at the CIRCE accelerator in Caserta, Italy and preliminary results are presented here
Immunonanogold Catalytic Resonance Scattering Spectral Assay of Trace Immunoglobulin M
Institute of Scientific and Technical Information of China (English)
LIANG Ai-Hui; WANG Su-Mei; JIANG Zhi-Liang
2008-01-01
Gold nanoparticles of 10 nm were prepared by the improved method of trisodium citrate, and used to label goat anti-human immunoglobulin M (anti-IgM) to obtain a resonance scattering spectral probe for IgM. In pH 4.5 KH2PO4-Na2HPO4 buffer solution and in the presence of polyethylene glycol, the nanogold-labeled anti-IgM was combined with IgM specifically to form immunogold complex particles. After centrifugation, the immunonanogold in the supernatant catalyzed the reduction of AuCl-4 ions by NH2OH·HCl to form larger size gold particles in pH 1.9 citrate buffer solution, making the resonance scattering intensity at 580 nm enhanced. The amount of the nanogold-labeled anti-IgM in the supernatant decreased with the addition of IgM. The decreased intensity △I580 nm was proportional to the concentration of IgM in the range of 0.06--4.80 ng·mL-1. The regression equation was △I580nm= 14.5c(IgM)+1.8, with a detection limit of 0.03 ng·mL-1 IgM. The method was applied to the determina-tion of IgM in sera of healthy humans, with satisfactory results.
Delta Electroproduction in 12-C
Energy Technology Data Exchange (ETDEWEB)
Steven McLauchlan
2003-01-31
The Delta-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the delta mass indicating that this potential is dependent on the momentum of the delta. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the delta resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4(pie) acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the delta mass was only observed in the exclusive measurements indicating that the delta-nucleus potential is affected by the momentum of the delta.
Institute of Scientific and Technical Information of China (English)
Yuan Bo; Wen Ji-Hong; Wen Xi-Sen
2013-01-01
A locally resonant sonic material (LRSM) is an elastic matrix containing a periodic arrangement of identical local resonators (LRs),which can reflect strongly near their natural frequencies,where the wavelength in the matrix is still much larger than the structural periodicity.Due to the periodic arrangement,an LRSM can also display a Bragg scattering effect,which is a characteristic of phononic crystals.A specific LRSM which possesses both local resonance and Bragg scattering effects is presented.Via the layered-multiple-scattering theory,the complex band structure and the transmittance of such LRSM are discussed in detail.Through the analysis of the refraction behavior at the boundary of the composite,we find that the transmittance performance of an LRSM for oblique incidence depends on the refraction of its boundary and the transmission behaviors of different wave modes inside the composite.As a result,it is better to use some low-speed materials (compared with the speed of waves in surrounding medium) as the LRSM matrix for designing sound blocking materials in underwater applications,since their acoustic properties are more robust to the incident angle.Finally,a gapcoupled LRSM with a broad sub-wavelength transmission gap is studied,whose acoustic performance is insensitive to the angle of incidence.
Scattering resonances of ultracold atoms in confined geometries
Energy Technology Data Exchange (ETDEWEB)
Saeidian, Shahpoor
2008-06-18
Subject of this thesis is the investigation of the quantum dynamics of ultracold atoms in confined geometries. We discuss the behavior of ground state atoms inside a 3D magnetic quadrupole field. Such atoms in enough weak magnetic fields can be approximately treated as neutral point-like particles. Complementary to the well-known positive energy resonances, we point out the existence of short-lived negative energy resonances. The latter originate from a fundamental symmetry of the underlying Hamiltonian. We drive a mapping of the two branches of the spectrum. Moreover, we analyze atomic hyperfine resonances in a magnetic quadrupole field. This corresponds to the case for which both the hyperfine and Zeeman interaction, are comparable, and should be taken into account. Finally, we develop a general grid method for multichannel scattering of two atoms in a two-dimensional harmonic confinement. With our approach we analyze transverse excitations/deexcitations in the course of the collisional process (distinguishable or identical atoms) including all important partial waves and their couplings due to the broken spherical symmetry. Special attention is paid to suggest a non-trivial extension of the CIRs theory developed so far only for the single-mode regime and zero-energy limit. (orig.)
Ruel, Chris
2013-01-01
Demystifying the power of the Oracle 12c database The Oracle database is the industry-leading relational database management system (RDMS) used from small companies to the world's largest enterprises alike for their most critical business and analytical processing. Oracle 12c includes industry leading enhancements to enable cloud computing and empowers users to manage both Big Data and traditional data structures faster and cheaper than ever before. Oracle 12c For Dummies is the perfect guide for a novice database administrator or an Oracle DBA who is new to Oracle 12c. The book covers what
Constraining the 12C+12C fusion cross section for astrophysics
Directory of Open Access Journals (Sweden)
Bucher B.
2015-01-01
Full Text Available The 12C+12C reaction is one of the single most important nuclear reactions in astrophysics. It strongly influences late evolution of massive stars as well as the dynamics of type Ia supernovae and x-ray superbursts. An accurate estimation of the cross section at relevant astrophysical energies is extremely important for modeling these systems. However, the situation is complicated by the unpredictable resonance structure observed at higher energies. Two recent studies at Notre Dame have produced results which help reduce the uncertainty associated with this reaction. The first uses correlations with the isotope fusion systems, 12C+13C and 13C+13C, to establish an upper limit on the resonance strengths in 12C+12C. The other focuses on the specific channel 12C+12C→23Mg+n and its low-energy measurement and extrapolation which is relevant to s-process nucleosynthesis. The results from each provide important constraints for astrophysical models.
Tuning Mie scattering resonances in soft materials with magnetic fields.
Brunet, Thomas; Zimny, Kevin; Mascaro, Benoit; Sandre, Olivier; Poncelet, Olivier; Aristégui, Christophe; Mondain-Monval, Olivier
2013-12-27
An original approach is proposed here to reversibly tune Mie scattering resonances occurring in random media by means of external low induction magnetic fields. This approach is valid for both electromagnetic and acoustic waves. The experimental demonstration is supported by ultrasound experiments performed on emulsions made of fluorinated ferrofluid spherical droplets dispersed in a Bingham fluid. We show that the electromagnet-induced change of droplet shape into prolate spheroids, with a moderate aspect ratio of 2.5, drastically affects the effective properties of the disordered medium. Its effective acoustic attenuation coefficient is shown to vary by a factor of 5, by controlling both the flux density and orientation of the applied magnetic field.
Tuning Mie scattering resonances in soft materials with magnetic fields.
Brunet, Thomas; Zimny, Kevin; Mascaro, Benoit; Sandre, Olivier; Poncelet, Olivier; Aristégui, Christophe; Mondain-Monval, Olivier
2013-12-27
An original approach is proposed here to reversibly tune Mie scattering resonances occurring in random media by means of external low induction magnetic fields. This approach is valid for both electromagnetic and acoustic waves. The experimental demonstration is supported by ultrasound experiments performed on emulsions made of fluorinated ferrofluid spherical droplets dispersed in a Bingham fluid. We show that the electromagnet-induced change of droplet shape into prolate spheroids, with a moderate aspect ratio of 2.5, drastically affects the effective properties of the disordered medium. Its effective acoustic attenuation coefficient is shown to vary by a factor of 5, by controlling both the flux density and orientation of the applied magnetic field. PMID:24483797
Electron- and neutrino-nucleus scattering from the quasielastic to the resonance region
Leitner, T; Alvarez-Ruso, L; Mosel, U
2008-01-01
We present a model for electron- and neutrino-scattering off nucleons and nuclei focussing on the quasielastic and resonance region. The lepton-nucleon reaction is described within a relativistic formalism that includes, besides quasielastic scattering, the excitation of 13 N* and Delta resonances and a non-resonant single-pion background. Recent electron-scattering data is used for the state-of-the-art parametrizations of the vector form factors; the axial couplings are determined via PCAC and, in the case of the Delta resonance, the axial form factor is refitted using neutrino-scattering data. Scattering off nuclei is treated within the GiBUU framework that takes into account various nuclear effects: the local density approximation for the nuclear ground state, mean-field potentials and in-medium spectral functions. Results for inclusive scattering off Oxygen are presented and, in the case of electron-induced reactions, compared to experimental data and other models.
Polaron hopping in olivine phosphates studied by nuclear resonant scattering
Tracy, Sally June
Valence fluctuations of Fe2+ and Fe3+ were studied in a solid solution of LixFePO4 by nuclear resonant forward scattering of synchrotron x rays while the sample was heated in a diamond-anvil pressure cell. The spectra acquired at different temperatures and pressures were analyzed for the frequencies of valence changes using the Blume-Tjon model of a system with a fluctuating Hamiltonian. These frequencies were analyzed to obtain activation energies and an activation volume for polaron hopping. There was a large suppression of hopping frequency with pressure, giving an anomalously large activation volume. This large, positive value is typical of ion diffusion, which indicates correlated motions of polarons, and Li+ ions that alter the dynamics of both. In a parallel study of NaxFePO4, the interplay between sodium ordering and electron mobility was investigated using a combination of synchrotron x-ray diffraction and nuclear resonant scattering. Conventional Mossbauer spectra were collected while the sample was heated in a resistive furnace. An analysis of the temperature evolution of the spectral shapes was used to identify the onset of fast electron hopping and determine the polaron hopping rate. Synchrotron x-ray diffraction measurements were carried out in the same temperature range. Reitveld analysis of the diffraction patterns was used to determine the temperature of sodium redistribution on the lattice. The diffraction analysis also provides new information about the phase stability of the system. The temperature evolution of the iron site occupancies from the Mossbauer measurements, combined with the synchrotron diffraction results give strong evidence for a relationship between the onset of fast electron dynamics and the redistribution of sodium in the lattice. Measurements of activation barriers for polaron hopping gave fundamental insights about the correlation between electronic carriers and mobile ions. This work established that polaron-ion interactions
Resonant inelastic scattering at intermediate X-ray energies
Hague, C F; Journel, L; Gallet, J J; Rogalev, A; Krill, G; Kappler, J P
2000-01-01
We describe resonant inelastic X-ray scattering (RIXS) experiments and magnetic circular dichroism (MCD) in X-ray fluorescence performed in the 3-5 keV range. The examples chosen are X-ray fluorescence MCD of FeRh and RIXS experiments performed at the L/sub 3/ edge of Ce. Fe Rh is antiferromagnetic at room temperature but has a transition to the ferromagnetic state above 400 K. The Rh MCD signal is compared with an augmented spherical wave calculation. The experiment confirms the predicted spin polarization of the Rh 4d valence states. The RIXS measurements on Ce compounds and intermetallics address the problem of mixed valency especially in systems where degeneracy with the Fermi level remains small. Examples are taken from the 2p to (4f5d) /sup +1/ followed by 3d to 2p RIXS for a highly ionic compound CeF /sub 3/ and for almost gamma -like CeCuSi. (38 refs).
Imaging instantaneous electron flow with ultrafast resonant x-ray scattering
Popova-Gorelova, Daria
2015-01-01
We propose a novel way to image dynamical properties of nonstationary electron systems using ultrafast resonant x-ray scattering. Employing a rigorous theoretical analysis within the framework of quantum electrodynamics, we demonstrate that a single scattering pattern from a nonstationary electron system encodes the instantaneous interatomic electron current in addition to the structural information usually obtained by resonant x-ray scattering from stationary systems. Thus, inelastic contributions that are indistinguishable from elastic processes induced by a broadband probe pulse, instead of being a concern, serve as an advantage for time-resolved resonant x-ray scattering. Thereby, we propose an approach combining elastic and inelastic resonant x-ray scattering for imaging dynamics of nonstationary electron systems in both real space and real time. In order to illustrate its power, we show how it can be applied to image the electron hole current in an ionized diatomic molecule.
Scattering of core-shell nanowires with the interference of electric and magnetic resonances.
Liu, Wei; Miroshnichenko, Andrey E; Oulton, Rupert F; Neshev, Dragomir N; Hess, Ortwin; Kivshar, Yuri S
2013-07-15
We study the scattering of normally incident waves by core-shell nanowires, which support both electric and magnetic resonances. Within such nanowires, for p-polarized incident waves, each electric resonance corresponds to two degenerate scattering channels while the magnetic resonance corresponds to only one channel. Consequently, when the electric dipole (ED) and magnetic dipole (MD) are tuned to overlap spectrally, the magnitude of the ED is twice that of the magnetic one, leading to a pair of angles of vanishing scattering. We further demonstrate that the scattering features of nanowires are polarization dependent, and vanishing scattering angles also can be induced by Fano resonances due to the interference of higher-order electric modes with the broad MD mode. PMID:23939129
Fano resonance-induced negative optical scattering force on plasmonic nanoparticles.
Chen, Huajin; Liu, Shiyang; Zi, Jian; Lin, Zhifang
2015-02-24
We demonstrate theoretically that Fano resonance can induce a negative optical scattering force acting on plasmonic nanoparticles in the visible light spectrum when an appropriate manipulating laser beam is adopted. Under the illumination of a zeroth-order Bessel beam, the plasmonic nanoparticle at its Fano resonance exhibits a much stronger forward scattering than backward scattering and consequently leads to a net longitudinal backward optical scattering force, termed Fano resonance-induced negative optical scattering force. The extinction spectra obtained based on the Mie theory show that the Fano resonance arises from the interference of simultaneously excited multipoles, which can be either a broad electric dipole mode and a narrow electric quadrupole mode, or a quadrupole and an octupole mode mediated by the broad electric dipole. Such Fano resonance-induced negative optical scattering force is demonstrated to occur for core-shell, homogeneous, and hollow metallic particles and can therefore be expected to be universal for many other nanostructures exhibiting Fano resonance, adding considerably to the flexibility of optical micromanipulation on the plasmonic nanoparticles. More interestingly, the flexible tunability of the Fano resonance by particle morphology opens up the possibility of tailoring the optical scattering force accordingly, offering an additional degree of freedom to optical selection and sorting of plasmonic nanoparticles. PMID:25635617
Effect of the third π ∗ resonance on the angular distributions for electron-pyrimidine scattering
Mašín, Zdeněk; Gorfinkiel, Jimena D.
2016-07-01
We present a detailed analysis of the effect of the well known third π∗ resonance on the angular behaviour of the elastic cross section in electron scattering from pyrimidine. This resonance, occurring approximately at 4.7 eV, is of mixed shape and core-excited character. Experimental and theoretical results show the presence of a peak/dip behaviour in this energy range, that is absent for other resonances. Our investigations show that the cause of the peak/dip is an interference of background p-wave to p-wave scattering amplitudes with the amplitudes for resonant scattering. The equivalent resonance in pyrazine shows the same behaviour and the effect is therefore likely to appear in other benzene-like molecules. Contribution to the Topical Issue "Advances in Positron and Electron Scattering", edited by Paulo Limao-Vieira, Gustavo Garcia, E. Krishnakumar, James Sullivan, Hajime Tanuma and Zoran Petrovic.
Indian Academy of Sciences (India)
Martin Freer
2014-11-01
The nucleus 12C has a rather significant role in modern nuclear physics, but whose influence can be traced to the work of Hoyle in the 1950s, when it was concluded that there should be a state close to 7.68 MeV responsible for the synthesis of carbon in stellar nucleosynthesis. Although a state at 7.65 MeV was subsequently discovered, its properties have remained something of a mystery until rather recently. This paper explores our current understanding of the structure of 12C, in particular the nature of the Hoyle state.
Magnetism in heterogeneous thin film systems: Resonant X-ray scattering studies
Kortright, J B; Bader, S D; Hellwig, O; Marguiles, D T; Fullerton, E E
2003-01-01
Magnetic and chemical heterogeneity are common in a broad range of magnetic thin film systems. Emerging resonant soft X-ray scattering techniques are well suited to resolve such heterogeneity at relevant length scales. Resonant X-ray magneto-optical Kerr effect measurements laterally average over heterogeneity but can provide depth resolution in different ways, as illustrated in measurements resolving reversible and irreversible changes in different layers of exchange-spring heterostructures. Resonant small-angle scattering measures in-plane heterogeneity and can resolve magnetic and chemical scattering sources in different ways, as illustrated in measurements of granular alloy recording media.
Importance of resonance widths in low-energy scattering of weakly bound light-mass nuclei
Fraser, P. R.; Massen-Hane, K.; Amos, K.; Bray, I.; Canton, L.; Fossión, R.; Kadyrov, A. S.; Karataglidis, S.; Svenne, J. P.; van der Knijff, D.
2016-09-01
What effect do particle-emitting resonances have on the scattering cross section? What physical considerations are necessary when modeling these resonances? These questions are important when theoretically describing scattering experiments with radioactive ion beams which investigate the frontiers of the table of nuclides, far from stability. Herein, a novel method is developed that describes resonant nuclear scattering from which centroids and widths in the compound nucleus are obtained when one of the interacting bodies has particle unstable resonances. The method gives cross sections without unphysical behavior that is found if simple Lorentzian forms are used to describe resonant target states. The resultant cross sections differ significantly from those obtained when the states in the coupled channel calculations are taken to have zero width, and compound-system resonances are better matched to observed values.
An Analysis of the $^{12}$C+$^{12}$C Reaction Using a New Type of Coupling Potential
Boztosun, I
2001-01-01
A new approach has been used to explain the experimental data for the $^{12}$C+$^{12}$C system over a wide energy range in the laboratory system from 32.0 MeV to 126.7 MeV. This new coupled-channels based approach involves replacing the usual first derivative coupling potential by a new, second-derivative coupling potential. This paper first shows and discusses the limitation of the standard coupled-channels theory in the case where one of the nuclei in the reaction is strongly deformed. Then, this new approach is shown to improve consistently the agreement with the experimental data: the elastic scattering, single-2$^{+}$ and mutual-2$^{+}$ excitation inelastic scattering data as well as their 90$^{\\circ}$ elastic and inelastic excitation functions with little energy-dependent potentials. This new approach makes major improvement on all the previous coupled-channels calculations for this system.
Siriwardana, Kumudu; Nettles, Charles B; Vithanage, Buddhini C N; Zhou, Yadong; Zou, Shengli; Zhang, Dongmao
2016-09-20
Existing studies on molecular fluorescence have almost exclusively been focused on Stokes-shifted fluorescence spectroscopy (SSF) in which the emitted photon is detected at the wavelengths longer than that for the excitation photons. Information on fluorophore on-resonance fluorescence (ORF) and resonance Rayleigh scattering (RRS) is limited and often problematic due to the complex interplay of the fluorophore photon absorption, ORF emission, RRS, and solvent Rayleigh scattering. Reported herein is a relatively large-scale systematic study on fluorophore ORF and RRS using the conventional UV-vis extinction and SSF measurements in combination with the recently reported ratiometric resonance synchronous spectroscopic (R2S2, pronounced as "R-Two-S-Two") method. A series of fundamental parameters including fluorophore ORF cross sections and quantum yields have been quantified for the first time for a total of 12 molecular and 6 semiconductor quantum dot (QD) fluorophores. All fluorophore spectra comprise a well-defined Gaussian peak with a full width at half-maximum ranging from 4 to 30 nm. However, the RRS features of fluorophores differ drastically. The effect of fluorophore aggregation on its RRS, UV-vis, R2S2, and SSF spectra was also discussed. This work highlights the critical importance of the combined UV-vis extinction, SSF, and R2S2 spectroscopic measurements for material characterizations. The method and insights described in this work can be directly used for improving the reliability of RRS spectroscopic methods in chemical analysis. In addition, it should pave the way for developing novel R2S2-based analytical applications.
New resonant inelastic X-ray scattering and coherent X-ray scattering station at UE49-SGM, BESSY II
International Nuclear Information System (INIS)
Soft x-ray scattering techniques are powerful probes for the understanding of nano- and atomic-scale phenomena, including magnetism, atomic motion and electronic structure. New beamline UE49-SGM and experimental stations are currently under construction, dedicated to the techniques of resonant inelastic x-ray scattering (RIXS) and coherent x-ray scattering (CXS). This facility will have the unique possibility to combine high-resolution spatial information studies with high-resolution chemically- and atomically-selective spectroscopy studies for a broad range of applications.
Use of nuclear resonant scattering of gamma rays for in vivo measurement of iron
Energy Technology Data Exchange (ETDEWEB)
Vartsky, D.; Wielopolski, L.; Ellis, K.J.; Cohn, S.H.
1981-01-01
A technique for determination of elements in human body in-vivo, utilizing nuclear resonant scattering of gamma rays has been developed. 847 keV photons emitted from a gaseous /sup 56/MnCl/sub 2/ source are resonantly scattered from /sup 56/Fe present in the body. The detection of these gamma rays is used to estimate the iron content of the liver or heart of patients. Details of the calibration procedure and potential molecular effects are described.
Xue, Jin-Hua; Qian, Qiu-Mei; Wang, Yong-Sheng; Meng, Xia-Ling; Liu, Lu
2013-02-01
A novel method of resonance light scattering (RLS) was developed for the analysis of trace metallothioneins (MTs) in human urine. In a CH3COOH-CH3COONa buffer solution of pH 4.5, the formation of a complex between levofloxacin (LEV)-Pd and MTs led to enhance the RLS intensity of the system, and the enhanced RLS intensity at 468 nm was proportional to the concentration of MTs in the range of 0.059-22.4 μg mL-1. The linear regression equation was ΔI = 127.5 ρ (μg mL-1)-88.02 with a correlation coefficient of 0.9992, and the detection limit of 17.8 ng mL-1. The relative standard deviation and the average recovery were 3.8-5.4% (n = 11) and 92.15%, respectively. The proposed method is convenient, reliable and sensitive, and has been used successfully for the determination of trace MTs in human urine samples.
Evidence for Resonance Scattering in the X-ray Spectrum of Zeta Puppis
Leutenegger, Maurice
2008-01-01
We present XMM-Newton Reflection Grating Spectrometer observations of pairs of X-ray emission line profiles from the 0 star Zeta Pup that originate from the same He-like ion. The two profiles in each pair have different shapes and cannot both be consistently fit by models assuming the same wind parameters. We show that the differences in profile shape can be accounted for in a model including the effects of resonance scattering, which affects the resonance line in the pair but not the intercombination line. This implies that resonance scattering is also important in single resonance lines, where its effect is difficult to distinguish from a low effective continuum optical depth in the wind. Thus, resonance scattering may help reconcile X-ray line profile shapes with literature mass-loss rates.
Resonance scattering in the X-ray emission line profiles of Zeta Puppis
Leutenegger, M A; Kahn, S M; Owocki, S P; Paerels, F B S
2007-01-01
We present XMM-Newton Reflection Grating Spectrometer observations of pairs of X-ray emission line profiles from the O star Zeta Pup that originate from the same He-like ion. The two profiles in each pair have different shapes and cannot both be consistently fit by models assuming the same wind parameters. We show that the differences in profile shape can be accounted for in a model including the effects of resonance scattering, which affects the resonance line in the pair but not the intercombination line. This implies that resonance scattering is also important in single resonance lines, where its effect is difficult to distinguish from a low effective continuum optical depth in the wind. Thus, resonance scattering may help reconcile X-ray line profile shapes with literature mass-loss rates.
Configuration resonance in scattering scanning near-field optical microscopy
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
A theoretical model is proposed in order to study the configuration resonance in s-SNOM. The electromagnetic coupling between the sample and the probe tip is described with the quasi-electrostatic field theory. This method permits us to analyze the configurational resonance evoked by the interaction between the probe tip and the sample in s-SNOM intuitively.The resonant conditions for a certain system are presented in an explicit form. On the condition of considering the actual size of the sample dipoles and the probe dipole, we discuss the possibility of realizing the configurational resonance for various material samples. The numerical results indicate that the polarizability of the dielectric probe tip is too small to arouse this resonance, whereas, with the surface plasmon resonance emerging on the metallic nanoparticles, the enhanced polarizability of the metallic probe tip ensures the requirements of fulfilling the resonance.
The limitations of resonant Compton scattering as a gamma-ray burst model
Brainerd, J. J.
1992-01-01
Resonant Compton upscattering is commended as a mechanism that produces a hard gamma-ray spectrum while suppressing X-rays. This model, however, has severe physical and observational limitations. Effective X-ray suppression places a lower limit on the electron density; above this limit X-rays scatter multiple times, so the single-scattering approximation of this mechanism is invalid. Multiple scattering produces a spectrum that is much harder than the single-scattering spectrum. As the Thomson optical depth of a power-law electron beam approaches unity, photon spawning commences at a high rate and physically invalidates the underlying electron distribution. The Compton upscattering model is therefore only valid over a narrow range of electron densities. An observational consequence of this model is the absence of the third cyclotron resonance. Resonant scattering produces gamma-rays that propagate nearly along the magnetic field. The resonant cross section of the third harmonic, which is strongly angle dependent, falls below the Compton continuum for these gamma rays. The observation of a third cyclotron resonance in a gamma-ray burst spectrum would eliminate resonant Compton scattering as a gamma-ray burst process.
Angular dependence of resonant inelastic x-ray scattering : A spherical tensor expansion
Juhin, Amelie; Brouder, Christian; de Groot, Frank
2014-01-01
A spherical tensor expansion is carried out to express the resonant inelastic scattering cross-section as a sum of products of fundamental spectra with tensors involving wavevectors and polarization vectors of incident and scattered photons. The expression presented in this paper differs from that o
α + 12C rotational bands in 16O
International Nuclear Information System (INIS)
The total quantum number N of the α + 12C rotational bands in 16O is determined by a study of α + 12C elastic scattering. The 8+ and 9- states are found around the excitation energy Ex = 30 MeV and they are the member of the known rotational bands. At the same time, the 02+ state (Ex = 6.05 MeV) is found to be dominated by N = 8. (author)
Resonant inelastic X-ray scattering of liquid water
Energy Technology Data Exchange (ETDEWEB)
Nilsson, Anders, E-mail: nilsson@slac.stanford.edu [SUNCAT Ctr Interface Sci and Catalysis, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Department of Physics, AlbaNova University Center, Stockholm University, SE-10691 (Sweden); Tokushima, Takashi [RIKEN/Spring-8, Sayo-cho, Sayo, Hyogo 679-5148 (Japan); Horikawa, Yuka [RIKEN/Spring-8, Sayo-cho, Sayo, Hyogo 679-5148 (Japan); Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Harada, Yoshihisa [RIKEN/Spring-8, Sayo-cho, Sayo, Hyogo 679-5148 (Japan); Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Synchrotron Radiation Research Organization, The University of Tokyo, Sayo-cho, Sayo, Hyogo 679-5165 (Japan); Ljungberg, Mathias P. [Department of Physics, AlbaNova University Center, Stockholm University, SE-10691 (Sweden); Institut de Ciencia de Materials de Barcelona (ICMAB-CSIC), Campus UAB, E-08193 Bellaterra (Spain); Shin, Shik [RIKEN/Spring-8, Sayo-cho, Sayo, Hyogo 679-5148 (Japan); Institute for Solid State Physics (ISSP), The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Synchrotron Radiation Research Organization, The University of Tokyo, Sayo-cho, Sayo, Hyogo 679-5165 (Japan); Pettersson, Lars G.M. [Department of Physics, AlbaNova University Center, Stockholm University, SE-10691 (Sweden)
2013-06-15
Highlights: ► Two peaks are observed in the lone pair region of the XES spectrum of water assigned to tetrahedral and distorted hydrogen bonding configurations. ► The isotope effect observed as different relative peak heights is due to spectral line shape differences. ► The two different hydrogen bonding environments can be related to local structures mimicking either low density water or high density water. -- Abstract: We review recent studies using resonant inelastic X-ray scattering (RIXS) or also here denoted X-ray emission spectroscopy (XES) on liquid water and the assignment of the two sharp peaks in the lone-pair region. Using the excitation energy dependence we connect the two peaks to specific features in the X-ray absorption (XAS) spectrum which have independently been assigned to molecules in tetrahedral or distorted configurations. The polarization dependence shows that both peaks are of 1b{sub 1} origin supporting an interpretation in terms of two structural species, tetrahedral or disordered, which is furthermore consistent with the temperature-dependence of the two peaks. We discuss effects of life-time vibrational interference and how this affects the two components differently and also leads to differences in the relative peak heights for H{sub 2}O and D{sub 2}O. We show furthermore that the inherent structure in molecular dynamics simulations contain the structural bimodality suggested by XES, but this is smeared out in the real structure when temperature is included. We present a discussion around alternative interpretations suggesting that the origin of the two peaks is related to ultrafast dissociation and show evidence that such a model is inconsistent with several experimental observations and theoretical concepts. We conclude that the peaks reflect a temperature-dependent balance in fluctuations between tetrahedral and disordered structures in the liquid. This is well-aligned with theories of water under supercooled conditions and
Resonance-Light-Scattering Study and Line-Shape Simulation of the J Band
Fidder, Henk; Wiersma, Douwe A.
1991-01-01
Line-shape simulations and resonance-light-scattering experiments of the J band in aggregates of pseudoisocyanine are reported. It is concluded that the J band can be described as a disordered Frenkel-exciton band with states that are pseudolocalized on segments of the aggregate chain. The resonance
Energy Technology Data Exchange (ETDEWEB)
Glover, C.J. [Department of Electronic Materials Engineering, Australian National University, Canberra, ACT 0200 (Australia); Schmitt, T. [SLS, Paul Scherrer Institut, PSI West, CH-5232 Villigen PSI (Switzerland); Mattesini, M. [Departamento de Fisica de la Tierra, Astronomia y Astrofisica I, Universidad Complutense de Madrid, E-28040 (Spain); Adell, M.; Ilver, L.; Kanski, J. [Chalmers University of Technology, SE-412 96 Goeteborg (Sweden); Kjeldgaard, L. [MAX-lab, Lund University, P.O. Box 118, SE-22100 Lund (Sweden); Agaker, M. [Department of Physics and Materials Science, Uppsala University, PO Box 530, SE-751 21 Uppsala (Sweden); Martensson, N. [MAX-lab, Lund University, P.O. Box 118, SE-22100 Lund (Sweden); Department of Physics and Materials Science, Uppsala University, PO Box 530, SE-751 21 Uppsala (Sweden); Ahuja, R.; Nordgren, J. [Department of Physics and Materials Science, Uppsala University, PO Box 530, SE-751 21 Uppsala (Sweden); Rubensson, J.-E. [Department of Physics and Materials Science, Uppsala University, PO Box 530, SE-751 21 Uppsala (Sweden)], E-mail: jan-erik.rubensson@fysik.uu.se
2009-07-15
Resonant inelastic soft X-ray scattering at the 3p resonances in crystalline Ge is presented. Both stationary and dispersive features are observed in a wide energy range above as well as below the ionization limits. These observations are in agreement with theoretical predictions based on a two-step model where the initially excited electron has no influence on the emission step. Excess population of states in the conduction band is found, and discussed in terms of attosecond electron dynamics.
Triple-resonant Brillouin light scattering in magneto-optical cavities
Haigh, J A; Ramsay, A J; Ferguson, A J
2016-01-01
An enhancement in Brillouin light scattering of optical photons with magnons is demonstrated in magneto-optical whispering gallery mode resonators tuned to a triple resonance point. This occurs when both the input and output optical modes are resonant with those of the whispering gallery resonator, with a separation given by the ferromagnetic resonance (FMR) frequency. The identification and excitation of specific optical modes allows us to gain a clear understanding of the mode-matching conditions. A selection rule due to wavevector matching leads to an intrinsic single-sideband excitation. Strong suppression of one sideband is essential for one-to-one frequency mapping in coherent optical-to-microwave conversion.
Microscopic description of α-cluster states in {sup 12}C
Energy Technology Data Exchange (ETDEWEB)
Neff, Thomas; Feldmeier, Hans [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany)
2014-07-01
The structure of {sup 12}C is investigated, using both a microscopic α-cluster model and fermionic molecular dynamics (FMD) where individual nucleons are considered as degrees freedom. In the FMD calculation an effective realistic interaction derived in the unitary correlation operator method (UCOM) is employed. By explicitly including {sup 8}Be+α channels resonances and scattering states above the three-α threshold can be investigated. Of particular interest are the second 0{sup +} state, the famous Hoyle state, and the second 2{sup +} state. Monopole and quadrupole transition strengths are analyzed and compared to experiment.
Gómez Camacho, A.
2016-07-01
CDCC calculations of elastic scattering angular distributions for reactions of the weakly bound projectile 6Li with targets 28Si and 58Ni at energies around the Coulomb barrier are presented. Special emphasis is given to account for the effect of couplings from 6Li resonance states l = 2, J π = 3+, 2+, 1+. Similarly, the effect produced by non-resonant state couplings is studied. The convergent calculations are carried out with global α-target and d-target interactions. The calculated elastic scattering angular distributions are in general in good agreement with the measurements for the systems considered in this work. It is found that the calculations with only resonance states are very similar to that with all couplings (resonance+non-resonance). So, the absence of these states have a strong effect on elastic scattering (non-resonance states calculation). It is shown that the effects increase as the collision energy increases. An interpretation of the strength of the different effects is given in terms of the polarization potentials that emerge from the different couplings.
Inclusive results for electron and photon scattering in the resonance region
Buss, O; Mosel, U; Alvarez-Ruso, L
2008-01-01
We present a model for electron scattering off nuclei and photon absorption in the resonance energy region (W <= 2 GeV). The elementary gamma/gamma* N-vertex is described using in-medium kinematics and up-to-date form factors for QE-scattering, pion-production form-factors and resonance helicity amplitudes of the MAID analysis. We find good agreement with inclusive data on electron scattering off Oxygen. For photon absorption in Carbon we find a large impact of the momentum dependent mean-field acting on initial- and final-state baryons.
Stability of Complex-Rotation Method on a Simple Resonant Scattering Problem
Institute of Scientific and Technical Information of China (English)
SHEN Li; WANG Lei; LIU Xiao-Jun; SHI Ting-Yun; LIU Hong-Ping
2008-01-01
@@ The stability of the complex-rotation method in B-spline basis for a simple atomic resonant scattering problem in free field is investigated. The numerical calculation shows that this method has a feature that the solution will not change in a wide range of rotation angle θ. Our determined scattering resonant energies and widths exactly coincide with the popularly accepted values. A new resonance is identified numerically although it is very broad.The norm of the complex eigenvalue, [E], is proposed to investigate and to evaluate the stability of the obtained complex eigenvalues.
Double-confocal resonator for X-ray generation via intracavity Thomson scattering
Energy Technology Data Exchange (ETDEWEB)
Xie, M. [Lawrence Berkeley Lab., CA (United States)
1995-12-31
There has been a growing interest in developing compact X-ray sources through Thomson scattering of a laser beam by a relativistic electron beam. For higher X-ray flux it is desirable to have the scattering to occur inside an optical resonator where the laser power is higher. In this paper I propose a double-confocal resonator design optimized for head-on Thomson scattering inside an FEL oscillator and analyze its performance taking into account the diffraction and FEL gain. A double confocal resonator is equivalent to two confocal resonators in series. Such a resonator has several advantages: it couples electron beam through and X-ray out of the cavity with holes on cavity mirrors, thus allowing the system to be compact; it supports the FEL mode with minimal diffraction loss through the holes; it provides a laser focus in the forward direction for a better mode overlap with the electron beam; and it provides a focus at the same location in the backward direction for higher Thomson scattering efficiency; in addition, the mode size at the focal point and hence the Rayleigh range can be adjusted simply through intracavity apertures; furthermore, it gives a large mode size at the mirrors to reduce power loading. Simulations as well as analytical results will be presented. Also other configurations of intracavity Thomson scattering where the double-confocal resonator could be useful will be discussed.
Institute of Scientific and Technical Information of China (English)
SONG Yan-qi; LIU Shao-pu; LIU Zhong-fang; HU Xiao-li
2011-01-01
In 0.1 mol/L HCl medium,12-tungstophosphoric(TP) acid reacted with matrine(Mat) and oxymatrine(Oxy)to form an ion-association complex.As a result,the new spectra of resonance Rayleigh scattering(RRS),second-order scattering(SOS) and frequency doubling scattering(FDS) appeared and their intensities were enhanced greatly.The maximum scattering wavelengths of RRS,SOS and FDS were located at 370,670 and 390 nm,respectively.The increments of scattering intensity were directly proportional to the concentration of Mat and Oxy in a certain range.Based on this,the method for the determination of matrine and oxymatrine has been established.It has been applied to the determination of matrine and oxymatrine in samples of Radix sophorae flavescentis with satisfactory result.The reaction mechanism and reasons of RRS enhancement were discussed.
Imaging interatomic electron current in crystals with ultrafast resonant x-ray scattering
Popova-Gorelova, Daria
2015-01-01
We demonstrate how the technique of ultrafast resonant x-ray scattering can be applied to imaging dynamics of electronic wave packets in crystals. We study scattering patterns from crystals with electron dynamics in valence bands taking into account that inelastic and elastic scattering events induced by a broad-band probe pulse cannot be separated through the spectroscopy of the scattered photon. As a result, scattering patterns are not determined by the structure factor at the time of measurement, but can encode the instantaneous electron current between scattering atoms. We provide examples of how the interatomic electron current in a periodic structure can be extracted from a single scattering pattern by considering valence electron hole motion in (KBr)$_{108}$ and Ge$_{83}$ clusters.
Shamsudeen, Riyaj; Yu, Kai; Farooq, Tariq
2013-01-01
Expert Oracle RAC 12c is a hands-on book helping you understand and implement Oracle Real Application Clusters (RAC), and to reduce the total-cost-of-ownership (TCO) of a RAC database. As a seasoned professional, you are probably aware of the importance of understanding the technical details behind the RAC stack. This book provides deep understanding of RAC concepts and implementation details that you can apply toward your day-to-day operational practices. You'll be guided in troubleshooting and avoiding trouble in your installation. Successful RAC operation hinges upon a fast-performing netwo
Resonance scattering, absorption and off-centre abundance peaks in clusters of galaxies
Sanders, J S
2006-01-01
A possible explanation for the central abundance dips found from spatially-resolved X-ray spectroscopy of several groups and clusters of galaxies is resonance scattering. A number of the prominent iron emission lines are resonance lines. We construct a unique spectral model which takes account of resonance scattering for several thousand resonance lines, projection effects, photoelectric absorption, and allows direct spectral fitting. We apply our model to Chandra observations of two clusters with pronounced central abundance dips, Centaurus and Abell 2199. The results show that the effect of resonance scattering on emission from the centre of the cluster can be as much as 30 per cent for the Fe-K resonance lines, and 10 per cent for several Fe-L lines, if turbulence is low. The change to the metallicities obtained by fitting low resolution CCD spectra is at most 10 per cent. Accounting for resonance scattering does not remove the central dip. Allowing for internal absorption within the Centaurus significantl...
Nuclear compton scattering in the delta resonance region
Energy Technology Data Exchange (ETDEWEB)
Carrasco, R.C. (Departamento de Tecnologia Informatica y Computacion. Universidad de Alicante. Alicante (Spain))
1994-01-01
We develop a model in which the Compton amplitude at intermediate energies is split into a resonant and a background part. The resonant amplitude and the imaginary part of the background amplitude are calculated using microscopic many body methods. The background real part is obtained by subtracting the resonant one to total real amplitude-evaluated by means of a dispersion relation at forward angles. Uncertainties remain on how to extrapolate this forward real background amplitude to backward angles and we study the repercussion of these uncertainties in the Compton cross section. (Author) 30 refs.
Implications of the ABC Resonance Structure on Elastic Neutron-Proton Scattering
Pricking, Annette; Clement, H
2013-01-01
In recent WASA-at-COSY measurements of the basic double-pionic fusion reactions $pn \\to d\\pi^0\\pi^0$ and $pn \\to d\\pi^+\\pi^-$ a narrow resonance structure with $I(J^P) = 0(3^+)$ in the total cross section has been found. If this constitutes a s-channel resonance in the $pn$ system, then it should cause distinctive consequences in $pn$ scattering. The magnitude of the decay width into the $pn$ channel is estimated and the expected resonance effects in integral and differential $pn$ scattering observables are presented. The inclusion of the resonance improves the description of total cross section data. For the analyzing power a characteristic energy dependence is predicted, which should allow a crucial experimental check of the resonance hypothesis.
Induced two-body scattering resonances from a square-well potential with oscillating depth
Hudson Smith, D.
2016-03-01
In systems of ultracold atoms, pairwise interactions can be resonantly enhanced by a new mechanism which does not rely upon a magnetic Feshbach resonance. In this mechanism, interactions are controlled by tuning the frequency of an oscillating parallel component of the magnetic field close to the Bohr frequency for the transition to a two-atom bound state. The real part of the s-wave scattering length a has a resonance as a function of the oscillation frequency near the Bohr frequency. The resonance parameters can be controlled by varying the amplitude of the oscillating field. The amplitude also controls the imaginary part of a which arises predominantly because the oscillating field converts atom pairs into molecules. For the case of a shallow bound state in the scattering channel, the dimensionless resonance parameters are universal functions of the dimensionless oscillation amplitude.
Narrow Near-Threshold Resonance in e+-He+ Scattering
Institute of Scientific and Technical Information of China (English)
LIU Min-Min; HAN Hui-Li; GU Si-Hong; SHI Ting-Yun
2012-01-01
An independent alternative calculation is performed for narrow near-threshold resonances in the e+-He+ system using the stabilization method in the framework of hyperspherical coordinates (HSSM).A narrow resonance at Er =-0.249995 with width T =1.9 × 10-5,associated with the He2+-Ps(n =1) threshold is confirmed.The resonances around the energies -0.365 and -0.195,predicted by Bhatia and Drachman [Phys.Rev.A 42 (1990)5117] and confirmed by Ho [Phys.Rev.A 53 (1996)3165],do not appear in our calculations.%An independent alternative calculation is performed for narrow near-threshold resonances in the e+-He+ system using the stabilization method in the framework of hyperspherical coordinates (HSSM). A narrow resonance at Er = -0.249995 with width r = 1.9 x 10-5, associated with the He2+-Ps(n = 1) threshold is confirmed. The resonances around the energies -0.365 and -0.195, predicted by Bhatia and Drachman [Phys. Rev. A 42(1990)5117] and confirmed by Ho [Phys. Rev. A 53 (1996) 3165], do not appear in our calculations.
Tunneling effects in resonant acoustic scattering of an air bubble in unbounded water
Directory of Open Access Journals (Sweden)
ANDRÉ G. SIMÃO
2016-06-01
Full Text Available Abstract The problem of acoustic scattering of a gaseous spherical bubble immersed within unbounded liquid surrounding is considered in this work. The theory of partial wave expansion related to this problem is revisited. A physical model based on the analogy between acoustic scattering and potential scattering in quantum mechanics is proposed to describe and interpret the acoustical natural oscillation modes of the bubble, namely, the resonances. In this context, a physical model is devised in order to describe the air water interface and the implications of the high density contrast on the various regimes of the scattering resonances. The main results are presented in terms of resonance lifetime periods and quality factors. The explicit numerical calculations are undertaken through an asymptotic analysis considering typical bubble dimensions and underwater sound wavelengths. It is shown that the resonance periods are scaled according to the Minnaert’s period, which is the short lived resonance mode, called breathing mode of the bubble. As expected, resonances with longer lifetimes lead to impressive cavity quality Q-factor ranging from 1010 to 105. The present theoretical findings lead to a better understanding of the energy storage mechanism in a bubbly medium.
Scattering of electromagnetic pulses by metal nanospheres in the vicinity of a Fano-like resonance
Astapenko, V. A.; Svita, S. Yu.
2015-06-01
In the work, radiation scattering by metal nanospheres in a dielectric matrix in case of ultrashort and long electromagnetic pulses is studied theoretically. Spectral efficiencies of backward and forward scattering by silver nanospheres in glass are calculated with the use of experimental data on the dielectric permittivity of silver. The presence of Fano-like resonances in spectral dependences of scattering efficiency caused by interference of dipole and quadrupole scatterings is shown. Backward and forward scattering of ultrashort pulses is calculated and analyzed. The obtained dependences of the total probability of scattering (during all time of the action of a pulse) on pulse duration demonstrate an essential distinction between an ultrashort case and a long pulse limit.
Scattering of electromagnetic pulses by metal nanospheres in the vicinity of a Fano-like resonance
Energy Technology Data Exchange (ETDEWEB)
Astapenko, V.A.; Svita, S.Yu., E-mail: sergey.svita@gmail.com
2015-06-26
In the work, radiation scattering by metal nanospheres in a dielectric matrix in case of ultrashort and long electromagnetic pulses is studied theoretically. Spectral efficiencies of backward and forward scattering by silver nanospheres in glass are calculated with the use of experimental data on the dielectric permittivity of silver. The presence of Fano-like resonances in spectral dependences of scattering efficiency caused by interference of dipole and quadrupole scatterings is shown. Backward and forward scattering of ultrashort pulses is calculated and analyzed. The obtained dependences of the total probability of scattering (during all time of the action of a pulse) on pulse duration demonstrate an essential distinction between an ultrashort case and a long pulse limit.
Scattering of electromagnetic pulses by metal nanospheres in the vicinity of a Fano-like resonance
International Nuclear Information System (INIS)
In the work, radiation scattering by metal nanospheres in a dielectric matrix in case of ultrashort and long electromagnetic pulses is studied theoretically. Spectral efficiencies of backward and forward scattering by silver nanospheres in glass are calculated with the use of experimental data on the dielectric permittivity of silver. The presence of Fano-like resonances in spectral dependences of scattering efficiency caused by interference of dipole and quadrupole scatterings is shown. Backward and forward scattering of ultrashort pulses is calculated and analyzed. The obtained dependences of the total probability of scattering (during all time of the action of a pulse) on pulse duration demonstrate an essential distinction between an ultrashort case and a long pulse limit
Nucleon Resonances in Meson Nucleon Scattering with Strangeness Production
Waluyo, A.; Bennhold, C.; Haberzettl, H.; Penner, G.; Mosel, U.; Mart, T.
2000-01-01
An effective Lagrangian model in a coupled channels framework is applied to extract nucleon resonance parameters. In the K-matrix approximation, we simultaneously analyze all the available data for the transitions from pi N to five possible meson-baryon final states, pi N, pipi N, eta N, K Lambda, and KSigma, in the energy range from pi N threshold up to W = 2 GeV. In this work, we focus our efforts on the K Sigma channel. In particular, we include a set of Delta resonances around 1900 MeV: t...
Experimental elucidation: microscopic mechanism of resonant X-ray scattering in manganite films
Ohsumi, H; Kiyama, T
2003-01-01
Resonant X-ray scattering experiments have been performed on perovskite manganite La sub 0 sub . sub 5 Sr sub 0 sub . sub 5 MnO sub 3 thin films, which are grown on three distinct perovskite with a coherent epitaxial strain and have a forced ferro-type orbital ordering of Mn 3d orbitals. Using an interference technique, we have successfully observed the resonant X-ray scattering signal from the system having the ferro-type orbital ordering and also revealed the energy scheme of Mn 4p bands. For the forced ferro-type orbital ordering system, the present results evidence that the resonant X-ray scattering signal originates from the band structure effect due to the Jahn-Teller distortion of a MnO sub 6 octahedron, and not from the Coulomb interaction between 3d and 4p electrons. (author)
Resonant Raman scattering theory for Kitaev models and their Majorana fermion boundary modes
Perreault, Brent; Knolle, Johannes; Perkins, Natalia B.; Burnell, F. J.
2016-09-01
We study the inelastic light scattering response in two- (2D) and three-dimensional (3D) Kitaev spin-liquid models with Majorana spinon band structures in the symmetry classes BDI and D leading to protected gapless surface modes. We present a detailed calculation of the resonant Raman/Brillouin scattering vertex relevant to iridate and ruthenate compounds whose low-energy physics is believed to be proximate to these spin-liquid phases. In the symmetry class BDI, we find that while the resonant scattering on thin films can detect the gapless boundary modes of spin liquids, the nonresonant processes do not couple to them. For the symmetry class D, however, we find that the coupling between both types of light-scattering processes and the low-energy surface states is strongly suppressed. Additionally, we describe the effect of weak time-reversal symmetry breaking perturbations on the bulk Raman response of these systems.
Resonant Raman scattering in GaSe and GaS/sub x/Se/sub 1-x/
Energy Technology Data Exchange (ETDEWEB)
Chiang, T.C.; Camassel, J.; Voitchovsky, J.P.; Shen, Y.R.
1976-07-01
Multiphonon resonant Raman scattering up to four phonons in GaSe and one and two phonon resonant Raman scattering in the mixed GaS/sub x/Se/sub 1 - x/ crystals with x less than or equal to 0.23 were investigated. The results can be explained by a simple theory in which the dispersion of the resonance behavior is mainly dominated by resonances with the 1s direct exciton state.
Angular dependence of resonant inelastic x-ray scattering: a spherical tensor expansion
Juhin Amélie; Brouder Christian; Groot Frank
2013-01-01
International audience A spherical tensor expansion is carried out to express the resonant inelastic scattering cross-section as a sum of products of fundamental spectra with tensors involving wavevectors and polarization vectors of incident and scattered photons. The expression presented in this paper differs from that of the influential article by Carra et al. (Phys. Rev. Lett. 74, 3700, 1995) because it does not omit interference terms between electric dipole and quadrupole contribution...
Institute of Scientific and Technical Information of China (English)
Li Li; Wen Ji-Hong; Cai Li; Zhao Hong-Gang; Wen Xi-Sen
2013-01-01
Using the multilayered cylinder model,we study acoustic scattering from a submerged cylindrical shell coated with locally resonant acoustic metamaterials,which exhibit locally negative effective mass densities.A spring model is introduced to replace the traditional transfer matrix,which may be singular in the negative mass region.The backscattering form function and the scattering cross section are calculated to discuss the acoustic properties of the coated submerged cylindrical shell.
Resonance scattering at third-order exceptional points
International Nuclear Information System (INIS)
We analyze scattering cross sections at and near third-order exceptional points (EP3), i.e., points in physical parameter space where three energies and eigenfunctions coincide. At an EP3, the Green’s function contains a pole of third order, in addition to poles of second and first order. We show that the interference of the three pole terms produces a rich variety of line shapes at the exceptional point and in its neighbourhood. This is demonstrated by extending previous work on two harmonic oscillators to a system of three driven coupled damped oscillators. We also discuss the similarities and the differences in the behaviour of the amplitudes in the classical problem and the scattering cross sections in the quantum mechanical problem at the EP3. (paper)
International workshop on resonant X-ray scattering in electrically-ordered systems
International Nuclear Information System (INIS)
The research field of Resonant X-ray Scattering (RXS) has achieved tremendous progress in the last years. Nowadays RXS is rapidly becoming the crucial technique for investigating the subtleties of microscopic magnetism in systems where the ground state properties reflect a delicate balance between several different correlated processes. The aim of this workshop is to discuss present and future possibilities for RXS investigations of electronic order, including studies of charge, magnetic, and multipolar ordered states. The sessions will cover experimental and theoretical aspects of hard and soft X-ray resonant scattering from single crystals and thin films. This document gathers the summaries of the presentations
International workshop on resonant X-ray scattering in electrically-ordered systems
Energy Technology Data Exchange (ETDEWEB)
Collins, S.P.; Pettifer, R.F.; Laundy, D.; Ishida, K.; Kokubun, J.; Giles, C.; Yokaichiya, F.; Song, C.; Lee, K.B.; Ji, S.; Koo, J.; Park, Y.J.; Kim, J.Y.; Park, J.H.; Shin, H.J.; Rhyee, J.S.; Oh, B.H.; Cho, B.K.; Wilkins Stuart, B.; Paixao, J.A.; Caciuffo, R.; Javorsky, P.; Wastin, F.; Rebizant, J.; Detlefs, C.; Bernheoft, N.; Lander, G.H.; Bombardi, A.; Bergevin, F. de; Matteo, S. di; Paolasini, L.; Rodriguez-Carvajal, J.; Carretta, P.; Millet, P.; Caciuffo, R.; Goff, J.P.; Deen, P.P.; Lee, S.; Stunault, A.; Brown, S.; Mannix, D.; McIntyre, G.J.; Ward, R.C.C.; Wells, M.R.; Lorenzo, J.E.; Joly, Y.; Nazarenko, E.; Staub, U.; Srajer, G.; Haskel, D.; Choi, Y.; Lee, D.R.; Lang, J.C.; Meersschaut, J.; Jiang, J.S.; Bader, S.D.; Bouchenoire, L.; Brown, S.D.; Beesley, A.; Herring, A.; Thomas, M.; Thompson, P.; Langridge, S.; Stirling, W.G.; Mirone, A.; Lander, G.; Wilkins, S.; Ward, R.C.C.; Wells, M.R.; Zochowski, S.W.; Garcia, J.; Subias, G.; Blasco, J.; Sanchez, M.C.; Proietti, M.G.; Lovesey, S.W.; Dmitrienko, V.E.; Ovchinnikova, E.N.; Ishida, K.; Kokubun, J.; Kirfel, A.; Collins, S.P.; Laundy, D.; Oreshko, A.P.; Strange, P.; Horne, M.; Arola, E.; Winter, H.; Szotek, Z.; Temmerman, W.M.; Igarashi, J.; Usuda, M.; Takahashi, M.; Matteo, S. di; Bernhoeft, N.; Hill, J.P.; Lang, J.C.; McWhan, D.; Lee, D.R.; Haskel, D.; Srajer, G.; Hatton Peter, D.; Katsumata, K.; Braithwaite, D
2004-07-01
The research field of Resonant X-ray Scattering (RXS) has achieved tremendous progress in the last years. Nowadays RXS is rapidly becoming the crucial technique for investigating the subtleties of microscopic magnetism in systems where the ground state properties reflect a delicate balance between several different correlated processes. The aim of this workshop is to discuss present and future possibilities for RXS investigations of electronic order, including studies of charge, magnetic, and multipolar ordered states. The sessions will cover experimental and theoretical aspects of hard and soft X-ray resonant scattering from single crystals and thin films. This document gathers the summaries of the presentations.
de Escobar, Y N Martinez; Yan, M; Killian, T C
2009-01-01
We demonstrate control of the scattering properties of atomic strontium with an optical Feshbach resonance near the 1S0-3P1 intercombination transition at 689 nm. Significant changes in scattering length on the order of plus/minus 10 a0 can be achieved at large detuning (~10e6 linewidths), and we are able to increase phase space density through enhanced evaporative cooling. Loss rate constants are at least two orders of magnitude smaller than in previous experiments with optical Feshbach resonances, but are three orders of magnitude larger than predicted.
Direct probe of anisotropy in atom-molecule collisions via quantum scattering resonances
Klein, Ayelet; Skomorowski, Wojciech; Żuchowski, Piotr S; Pawlak, Mariusz; Janssen, Liesbeth M C; Moiseyev, Nimrod; van de Meerakker, Sebastiaan Y T; van der Avoird, Ad; Koch, Christiane P; Narevicius, Edvardas
2016-01-01
Anisotropy is a fundamental property of particle interactions. It occupies a central role in cold and ultra-cold molecular processes, where long range forces have been found to significantly depend on orientation in ultra-cold polar molecule collisions. Recent experiments have demonstrated the emergence of quantum phenomena such as scattering resonances in the cold collisions regime due to quantization of the intermolecular degrees of freedom. Although these states have been shown to be sensitive to interaction details, the effect of anisotropy on quantum resonances has eluded experimental observation so far. Here, we directly measure the anisotropy in atom-molecule interactions via quantum resonances by changing the quantum state of the internal molecular rotor. We observe that a quantum scattering resonance at a collision energy of $k_B$ x 270 mK appears in the Penning ionization of molecular hydrogen with metastable helium only if the molecule is rotationally excited. We use state of the art ab initio and ...
Exploring the extended scalar sector with resonances in vector boson scattering
Khan, Najimuddin; Rakshit, Subhendu; Shaw, Avirup
2016-01-01
We show that the study of scalar resonances at various vector boson scattering processes at the Large Hadron Collider can serve as a useful tool to distinguish between different extensions of the scalar sector of the Standard Model. The recent measurement of the Higgs boson properties leaves enough room for the extended scalar sectors to be relevant for such studies. The shape of the resonances, being model dependent, can shed light on the viable parameter space of a number of theoretical models.
Hyper-Raman scattering and three-photon resonant ionization: Competitive effects
International Nuclear Information System (INIS)
A semiclassical theory of hyper-Raman scattering and three-photon resonant ionization via the coupled density-matrix and Maxwell equations is presented. A simplified three-level atom model is obtained, which includes two-photon resonant pumping and time dependent photoionization rates. We consider conditions typically encountered in atomic vapours to simulate numerically pulse propagation. A strong depletion of the photoionization probability in the hyper-Raman field saturation regime is predicted. (author). 17 refs, 8 figs
Correlations between resonances in a statistical scattering model
Gorin, T; Müller, M; Rotter, I; Seligman, T H
1997-01-01
The distortion of the regular motion in a quantum system by its coupling to the continuum of decay channels is investigated. The regular motion is described by means of a Poissonian ensemble. We focus on the case of only few channels K<10. The coupling to the continuum induces two main effects, due to which the distorted system differs from a chaotic system (described by a Gaussian ensemble): 1. The width distribution for large coupling becomes broader than the corresponding $\\chi^2_K$ distribution in the GOE case. 2. Due to the coupling to the continuum, correlations are induced not only between the positions of the resonances but also between positions and widths. These correlations remain even in the strong coupling limit. In order to explain these results, an asymptotic expression for the width distribution is derived for the one channel case. It relates the width of a trapped resonance state to the distance between its two neighboring levels.
Correlations between resonances in a statistical scattering model
Energy Technology Data Exchange (ETDEWEB)
Gorin, T. [Technische Univ. Dresden (Germany). Inst. fuer Theoretische Physik]|[Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany). Inst. fuer Kern- und Hadronenphysik; Dittes, F.M. [Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany). Inst. fuer Kern- und Hadronenphysik; Mueller, M. [Centro Internacional de Ciencias, Cuernavaca (Mexico); Rotter, I. [Technische Univ. Dresden (Germany). Inst. fuer Theoretische Physik]|[Forschungszentrum Rossendorf e.V. (FZR), Dresden (Germany). Inst. fuer Kern- und Hadronenphysik; Seligman, T.H. [Centro Internacional de Ciencias, Cuernavaca (Mexico)
1997-01-01
The distortion of the regular motion in a quantum system by its coupling to the continuum of decay channels is investigated. The regular motion is described by means of a Poissonian ensemble. We focus on the case of only few channels K < 10. The coupling to the continuum induces two main effects, due to which the distorted system differs from a chaotic system (described by a Gaussian ensemble): 1. The width distribution for large coupling becomes broader than the corresponding {chi}{sup 2}{sub K} distribution in the GOE case. 2. Due to the coupling to the continuum, correlations are induced not only between the positions of the resonances but also between positions and widths. These correlations remain even in the strong coupling limit. In order to explain these results, an asymptotic expression for the width distribution is derived for the one channel case. It relates the width of a trapped resonance state to the distance between its two neighboring levels. (orig.)
Toroidal silicon polarization analyzer for resonant inelastic x-ray scattering.
Gao, Xuan; Casa, Diego; Kim, Jungho; Gog, Thomas; Li, Chengyang; Burns, Clement
2016-08-01
Resonant Inelastic X-ray Scattering (RIXS) is a powerful probe for studying electronic excitations in materials. Standard high energy RIXS measurements do not measure the polarization of the scattered x-rays, which is unfortunate since it carries information about the nature and symmetry of the excitations involved in the scattering process. Here we report the fabrication of thin Si-based polarization analyzers with a double-concave toroidal surface, useful for L-edge RIXS studies in heavier atoms such as the 5-d transition metals.
Dynamic neutron scattering on incoherent systems using efficient resonance spin flip techniques
Energy Technology Data Exchange (ETDEWEB)
Häussler, Wolfgang [Heinz Maier-Leibnitz Zentrum, Technische Universität München, D-85748 Garching, Germany and Physik-Department E21, Technische Universität München, D-85748 Garching (Germany); Kredler, Lukas [Physik-Department E21, Technische Universität München, D-85748 Garching (Germany)
2014-05-15
We have performed numerical ray-tracing Monte-Carlo-simulations of incoherent dynamic neutron scattering experiments. We intend to optimize the efficiency of incoherent measurements depending on the fraction of neutrons scattered without and with spin flip at the sample. In addition to conventional spin echo, we have numerically and experimentally studied oscillating intensity techniques. The results point out the advantages of these different spin echo variants and are an important prerequisite for neutron resonance spin echo instruments like RESEDA (FRM II, Munich), to choose the most efficient technique depending on the scattering vector range and the properties of the sample system under study.
Toroidal silicon polarization analyzer for resonant inelastic x-ray scattering
Gao, Xuan; Casa, Diego; Kim, Jungho; Gog, Thomas; Li, Chengyang; Burns, Clement
2016-08-01
Resonant Inelastic X-ray Scattering (RIXS) is a powerful probe for studying electronic excitations in materials. Standard high energy RIXS measurements do not measure the polarization of the scattered x-rays, which is unfortunate since it carries information about the nature and symmetry of the excitations involved in the scattering process. Here we report the fabrication of thin Si-based polarization analyzers with a double-concave toroidal surface, useful for L-edge RIXS studies in heavier atoms such as the 5-d transition metals.
Toroidal silicon polarization analyzer for resonant inelastic x-ray scattering.
Gao, Xuan; Casa, Diego; Kim, Jungho; Gog, Thomas; Li, Chengyang; Burns, Clement
2016-08-01
Resonant Inelastic X-ray Scattering (RIXS) is a powerful probe for studying electronic excitations in materials. Standard high energy RIXS measurements do not measure the polarization of the scattered x-rays, which is unfortunate since it carries information about the nature and symmetry of the excitations involved in the scattering process. Here we report the fabrication of thin Si-based polarization analyzers with a double-concave toroidal surface, useful for L-edge RIXS studies in heavier atoms such as the 5-d transition metals. PMID:27587100
Non-central interactions in 12C(p,p')12C*(1+; 15.11 MeV)
International Nuclear Information System (INIS)
Spin dependent non-central interactions were introduced into nuclear physics when Schwinger proposed the NN tensor interaction to explain the observed quadrupole moment of the deuteron. The present paper discusses the nature of non-central forces that come into play in inelastic scattering of nucleons on 12C
New determination of 12C(α,γ)16O reaction rate
Oulebsir, N.
2015-12-01
The reaction 12C(α,γ)16O was investigated through the direct α-transfer reaction (7Li,t) at 28 and 34 MeV incident energies. We determined the reduced α-widths of the sub-threshold 2+ and 1- states of 16O from the DWBA analysis of the transfer reaction 12C(7Li,t)16O performed at two incident energies. The obtained result for the 2+ and 1- sub-threshold resonances as introduced in the R-matrix fitting of radiative capture and elastic-scattering data to determine the E2 and E1 S-factor from 0.01MeV to 4.2MeV in the center-of-mass energy. After determining the astrophysic factor of 12C(α,γ)16O S(E) with Pierre Descouvement code, I determined numerically the new reaction rate of this reaction at a different stellar temperature (0.06 Gk-2 GK). The 12C(α,γ)16O reaction rate at T9 = 0.2 is [7.21-2.25+2.15] × 10-15 cm3 s-1 mol-1. Some comparisons and discussions about our new 12C(α,γ)16O reaction rate are presented. The agreements of the reaction rate below T9 = 2 between our results and with those proposed by NACRE indicate that our results are reliable, and they could be included in the astrophysical reaction rate network.
Multiple scattering dynamics of fermions at an isolated p-wave resonance
Thomas, Ryan; Tiesinga, Eite; Wade, Andrew C J; Blakie, P Blair; Deb, Amita B; Kjærgaard, Niels
2016-01-01
The wavefunction for indistinguishable fermions is anti-symmetric under particle exchange, which directly leads to the Pauli exclusion principle, and hence underlies the structure of atoms and the properties of almost all materials. In the dynamics of collisions between two indistinguishable fermions this requirement strictly prohibits scattering into 90 degree angles. Here we experimentally investigate the collisions of ultracold clouds fermionic $\\rm^{40}K$ atoms by directly measuring scattering distributions. With increasing collision energy we identify the Wigner threshold for p-wave scattering with its tell-tale dumb-bell shape and no $90^\\circ$ yield. Above this threshold effects of multiple scattering become manifest as deviations from the underlying binary p-wave shape, adding particles either isotropically or axially. A shape resonance for $\\rm^{40}K$ facilitates the separate observation of these two processes. The isotropically enhanced multiple scattering mode is a generic p-wave threshold phenomen...
Resonances in coupled ?K, ?K scattering from lattice QCD
Wilson, David J.; Dudek, Jozef J.; Edwards, Robert G.; Thomas, Christopher E.
2015-01-01
Coupled-channel $\\pi K$ and $\\eta K$ scattering amplitudes are determined by studying the finite-volume energy spectra obtained from dynamical lattice QCD calculations. Using a large basis of interpolating operators, including both those resembling a $q\\bar{q}$ construction and those resembling a pair of mesons with relative momentum, a reliable excited-state spectrum can be obtained. Working at ${m_\\pi=391\\,\\mathrm{MeV}}$, we find a gradual increase in the $J^P=0^+$ $\\pi K$ phase-shift which...
Scattering phase shift for elastic two pion scattering and the rho resonance in lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Gutzwiller, Simone
2012-10-08
In this thesis we use lattice QCD to compute scattering phase shifts for elastic two-pion scattering in the isospin I=1 channel. Using Luescher's formalism, we derive the scattering phase shifts for different total momenta of the two-pion system in a non-rest frame. Furthermore we analyse the symmetries of the non-rest frame lattices and construct 2-pion and rho operators transforming in accordance with these symmetries. The data was collected for a 32{sup 3} x 64 and a 40{sup 3} x 64 lattice with N{sub f}=2 clover improved Wilson fermions at a pion mass around 290 MeV and a lattice spacing of about 0.072 fm.
High-sensitivity pesticide detection using particle-enhanced resonant Raman scattering
Ranjan, Bikas; Saito, Yuika; Verma, Prabhat
2016-03-01
The use of pesticides in agriculture has raised concerns, as even a small residual of pesticide on food can be harmful. It is therefore of great importance to develop a robust technique to detect tiny amounts of pesticides. Although Raman spectroscopy is frequently used for chemical identification, it is not suitable for extremely low molecular concentrations. We propose a technique called particle-enhanced resonant Raman spectroscopy to detect extremely low concentrations of pesticides, where gold nanoparticles of desired plasmonic resonance are synthesized to match the resonance in Raman scattering. We successfully demonstrated the detection of extremely low amounts of pesticides on oranges.
Effective theory calculation of resonant high-energy scattering
Beneke, Martin; Signer, A; Zanderighi, G
2004-01-01
Tests of the standard model and its hypothetical extensions require precise theoretical predictions for processes involving massive, unstable particles. It is well-known that ordinary weak-coupling perturbation theory breaks down due to intermediate singular propagators. Various pragmatic approaches have been developed to deal with this difficulty. In this paper we construct an effective field theory for resonant processes utilizing the hierarchy of scales between the mass of the unstable particle, M, and its width, Gamma. The effective theory allows calculations to be systematically arranged into a series in g^2 and Gamma/M, and preserves gauge invariance in every step. We demonstrate the applicability of this method by calculating explicitly the inclusive line shape of a scalar resonance in an abelian gauge-Yukawa model at next-to-leading order in Gamma/M and the weak couplings. We also discuss the extension to next-to-next-to-leading order and compute an interesting subset of these corrections.
Resonant Scattering off Magnetic Impurities in Graphene: Mechanism for Ultrafast Spin Relaxation
Kochan, D.; Gmitra, M.; Fabian, J.
We give a tutorial account of our recently proposed mechanism for spin relaxation based on spin-flip resonant scattering off local magnetic moments. The mechanism is rather general, working in any material with a resonant local moment, but we believe that its particular niche is graphene, whose measured spin relaxation time is 100-1000 ps. Conventional spin-orbit coupling based mechanisms (Elliott-Yafet or Dyakonov-Perel) would require large concentrations (1000 ppm) of impurities to explain this. Our mechanism needs only 1 ppm of resonant local moments, as these act as local spin hot spots: the resonant scatterers do not appear to substantially affect graphene's measured resistivity, but are dominating spin relaxation. In principle, the local moments can come from a variety of sources. Most likely would be organic molecule adsorbants or metallic adatoms. As the representative model, particularly suited for a tutorial, we consider hydrogen adatoms which are theoretically and experimentally demonstrated to yield local magnetic moments when chemisorbed on graphene. We introduce the scattering formalism and apply it to graphene, to obtain the T-matrix and spin-flip scattering rates using the generalized Fermi golden rule.
Lamb, D. Q.; Wang, J. C. L.; Wasserman, I.
1992-01-01
We explain the relative line strengths in gamma-ray bursts in terms of cyclotron resonant scattering. We describe the line signature of neutron star rotation and discuss the possibility that variations seen in the strengths and widths of the lines in GB780325 and GB870303 are due to rotation.
RESONANT MAGNETIC-X-RAY SCATTERING FROM MIXED-VALENCE TMSE
MCWHAN, DB; ISAACS, ED; CARRA, P; SHAPIRO, SM; THOLE, BT; HOSHINO, S
1993-01-01
The mixed-valent compound TmSe has been studied in its antiferromagnetic state (T
X-ray resonant scattering study of the quadrupolar order in UPd_{3}
DEFF Research Database (Denmark)
McMorrow, D.F.; McEwen, K.A.; Steigenberger, U.;
2001-01-01
Quadrupolar ordering in a 5f electron system has been observed directly for the first time, using x-ray scattering techniques. In UPd(3) at low temperatures satellite peaks appear at (1, 0, l) (orthorhombic notation) with I odd and even. Both sets of peaks show a resonant enhancement of the scatt...
On the Possibility of Resonances in Longitudinally Polarized Vector Boson Scattering
Veltman, M.J.G.; Veltman, H.
1991-01-01
Assuming that no Higgs has been found below 1 TeV, we study the physics of longitudinally polarized vector boson ( ) scattering in the TeV region, using a one loop calculation and partial wave analysis. We show that the occurrence of a resonance in the isospin I = 1 channel depends on a certain para
Institute of Scientific and Technical Information of China (English)
Liu; Xiao-ling; Cai; Ru-xiu; 等
2003-01-01
In this paper, we used resonance light-scattering (RLS) spectroscopy to study the interaction betwwen thiolcontaining pharmaceutical and gold colloid. And for the first time, we proposed that this highly sensitive, gold colloidbased assay using RLS technique may have potential application in detecting thoil-containing substances.
Institute of Scientific and Technical Information of China (English)
Liu Xiao-ling; Cai Ru-xiu; Yuan Hong
2003-01-01
In this paper, we used resonance light-scattering (RLS) spectroscopy to study the interaction between thiol-containing pharmaceutical and gold colloid. And for the first time, we proposed that this highly sensitive, gold colloid-based assay using RLS technique may have potential application in detecting thiol-containing substances.
Nuclear resonant scattering of Synchrotron radiation from nuclei in the Browninan motion
Razdan, Ashok
2001-01-01
The time evolution of the coherent forward scattering of Synchrotron radiation for resonant nuclei in Brownian motion is studied . Apart from target thickness, the appearance of dynamical beats also depends on $\\alpha$ which is the ratio of harmonic force constant to the damping force constant of a harmonic oscillator undergoing Brownian motion.
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
The proton resonant properties in 18Ne, which determine the reaction rate of the key stellar 14O(α,p)17F reaction, have been studied by using a technique of proton resonant elastic scattering of 17F+p. A 4.22 MeV/nucleon 17F radioactive ion (RI) beam was produced via a projectile-fragmentation reaction, and separated by a Radioactive Ion Beam Line in Lanzhou (RIBLL). By bombarding a thick (CH2)n target, the energy spectra of the recoiled protons were measured by two ΔE-E silicon telescopes at the center-of-mass scattering angles of θc.m.≈175°±5°, θc.m.≈152°±8°, respectively. Several proton resonances in 18Ne were ob served clearly. A further R-matrix analysis of the experimental data is under way to determine the resonant parameters. The present work reports the preliminary results briefly.
Van Compernolle, B; Bortnik, J; Pribyl, P; Gekelman, W; Nakamoto, M; Tao, X; Thorne, R M
2014-04-11
Resonant interactions between energetic electrons and whistler mode waves are an essential ingredient in the space environment, and in particular in controlling the dynamic variability of Earth's natural radiation belts, which is a topic of extreme interest at the moment. Although the theory describing resonant wave-particle interaction has been present for several decades, it has not been hitherto tested in a controlled laboratory setting. In the present Letter we report on the first laboratory experiment to directly detect resonant pitch angle scattering of energetic (∼keV) electrons due to whistler mode waves. We show that the whistler mode wave deflects energetic electrons at precisely the predicted resonant energy, and that varying both the maximum beam energy, and the wave frequency, alters the energetic electron beam very close to the resonant energy.
Studies of reaction mechanism in 12C + 12C system at intermediate energy of 28.7 MeV/N
International Nuclear Information System (INIS)
The reaction mechanism in 12C + 12C system at intermediate energy of about 30 MeV/nucleon was studied. The contribution of various reaction mechanisms (inelastic scattering, transfer reactions, compound nucleus reactions, sequential decay following inelastic excitation and transfer) to the total reaction cross section were found. The analysis of inclusive and coincidence spectra shows that sequential fragmentation processes dominate
Nasr, Mamdouh H; Eshrah, Islam A; Abuelfadl, Tamer M
2016-01-01
An eigenmode projection technique (EPT) is developed and employed to solve problems of electromagnetic resonance in closed cavities and scattering from discontinuities in guided-wave structures. The EPT invokes the eigenmodes of a canonical predefined cavity in the solution procedure and uses the expansion of these eigenmodes to solve Maxwell's equations, in conjunction with a convenient choice of port boundary conditions. For closed cavities, resonance frequencies of arbitrary-shaped cavities are accurately determined with a robust and efficient separation method of spurious modes. For waveguide scattering problems, the EPT is combined with the generalized scattering matrix approach to solve problems involving waveguide discontinuities with arbitrary dielectric profiles. Convergence studies show stable solutions for a relatively small number of expansion modes, and the proposed method shows great robustness over conventional solvers in analyzing electromagnetic problems with inhomogeneous materials.
An ab initio study of multiple phonon scattering resonances in silicon germanium alloys
Mendoza, Jonathan; Esfarjani, Keivan; Chen, Gang
2015-05-01
We have computed phonon scattering rates and density of states in silicon germanium alloys using Green's function calculations and density functional theory. This method contrasts with the virtual crystal approximation (VCA) used in conjunction with Fermi's golden rule, which cannot capture resonance states occurring through the interaction of substitutional impurities with the host lattice. These resonances are demonstrated by density of states and scattering rate calculations in the dilute limit and show broadening as the concentration increases. Although these deviations become significant from the VCA at high frequencies, the relaxation times obtained for these phonon modes are small in both the full scattering theory and the VCA, resulting in their negligible contribution to thermal transport.
Advances in gamma ray resonant scattering and absorption long-lived isomeric nuclear states
Davydov, Andrey V
2015-01-01
This book presents the basics and advanced topics of research of gamma ray physics. It describes measuring of Fermi surfaces with gamma resonance spectroscopy and the theory of angular distributions of resonantly scattered gamma rays. The dependence of excited-nuclei average lifetime on the shape of the exciting-radiation spectrum and electron binding energies in the spectra of scattered gamma rays is described. Resonant excitation by gamma rays of nuclear isomeric states with long lifetime leads to the emission and absorption lines. In the book, a new gamma spectroscopic method, gravitational gamma spectrometry, is developed. It has a resolution hundred million times higher than the usual Mössbauer spectrometer. Another important topic of this book is resonant scattering of annihilation quanta by nuclei with excited states in connection with positron annihilation. The application of the methods described is to explain the phenomenon of Coulomb fragmentation of gamma-source molecules and resonant scatt...
Optically resonant magneto-electric cubic nanoantennas for ultra-directional light scattering
Energy Technology Data Exchange (ETDEWEB)
Sikdar, Debabrata, E-mail: debabrata.sikdar@monash.edu; Premaratne, Malin [Advanced Computing and Simulation Laboratory (A chi L), Department of Electrical and Computer Systems Engineering, Monash University, Clayton 3800, Victoria (Australia); Cheng, Wenlong [Department of Chemical Engineering, Faculty of Engineering, Monash University, Clayton 3800, Victoria (Australia); The Melbourne Centre for Nanofabrication, 151 Wellington Road, Clayton 3168, Victoria (Australia)
2015-02-28
Cubic dielectric nanoparticles are promising candidates for futuristic low-loss, ultra-compact, nanophotonic applications owing to their larger optical coefficients, greater packing density, and relative ease of fabrication as compared to spherical nanoparticles; besides possessing negligible heating at nanoscale in contrast to their metallic counterparts. Here, we present the first theoretical demonstration of azimuthally symmetric, ultra-directional Kerker's-type scattering of simple dielectric nanocubes in visible and near-infrared regions via simultaneous excitation and interference of optically induced electric- and magnetic-resonances up to quadrupolar modes. Unidirectional forward-scattering by individual nanocubes is observed at the first generalized-Kerker's condition for backward-scattering suppression, having equal electric- and magnetic-dipolar responses. Both directionality and magnitude of these unidirectional-scattering patterns get enhanced where matching electric- and magnetic-quadrupolar responses spectrally overlap. While preserving azimuthal-symmetry and backscattering suppression, a nanocube homodimer provides further directionality improvement for increasing interparticle gap, but with reduced main-lobe magnitude due to emergence of side-scattering lobes from diffraction-grating effect. We thoroughly investigate the influence of interparticle gap on scattering patterns and propose optimal range of gap for minimizing side-scattering lobes. Besides suppressing undesired side-lobes, significant enhancement in scattering magnitude and directionality is attained with increasing number of nanocubes forming a linear chain. Optimal directionality, i.e., the narrowest main-scattering lobe, is found at the wavelength of interfering quadrupolar resonances; whereas the largest main-lobe magnitude is observed at the wavelength satisfying the first Kerker's condition. These unique optical properties of dielectric nanocubes thus can
Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity
Guddala, Sriram; Dwivedi, Vindesh K.; Vijaya Prakash, G.; Narayana Rao, D.
2013-12-01
Here, we report the photon-plasmon interaction scheme and enhanced field strengths resulted into the amplification of phonon in a novel microcavity. A metal-dielectric microcavity, with unified cavity photonic mode and localized surface plasmon resonances, is visualized by impregnating the gold nanoparticles into the deep see-through nano-sized pores of porous silicon microcavity. The intense optical field strengths resulting from the photon-plasmon interactions are probed by both resonant and non-resonant Raman scattering experiments. Due to photon-plasmon-phonon interaction mechanism, several orders of enhancement in the intensity of scattered Raman Stokes photon (at 500 cm-1) are observed. Our metal nanoparticle-microcavity hybrid system shows the potential to improve the sensing figure of merit as well as the applications of plasmonics for optoelectronics, photovoltaics, and related technologies.
Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity
Energy Technology Data Exchange (ETDEWEB)
Guddala, Sriram; Narayana Rao, D., E-mail: dnr.laserlab@gmail.com, E-mail: dnrsp@uohyd.ernet.in [School of Physics, University of Hyderabad, Hyderabad 500 046 (India); Dwivedi, Vindesh K.; Vijaya Prakash, G. [Nanophotonics Laboratory, Department of Physics, IIT Delhi, New Delhi 110 016 (India)
2013-12-14
Here, we report the photon-plasmon interaction scheme and enhanced field strengths resulted into the amplification of phonon in a novel microcavity. A metal-dielectric microcavity, with unified cavity photonic mode and localized surface plasmon resonances, is visualized by impregnating the gold nanoparticles into the deep see-through nano-sized pores of porous silicon microcavity. The intense optical field strengths resulting from the photon-plasmon interactions are probed by both resonant and non-resonant Raman scattering experiments. Due to photon-plasmon-phonon interaction mechanism, several orders of enhancement in the intensity of scattered Raman Stokes photon (at 500 cm{sup −1}) are observed. Our metal nanoparticle-microcavity hybrid system shows the potential to improve the sensing figure of merit as well as the applications of plasmonics for optoelectronics, photovoltaics, and related technologies.
Resonant scattering of X-ray emission lines in the hot intergalactic medium
Churazov, E; Sazonov, S; Sunyaev, R
2010-01-01
While very often a hot intergalactic medium (IGM) is optically thin to continuum radiation, the optical depth in resonant lines can be of order unity or larger. Resonant scattering in the brightest X-ray emission lines can cause distortions in the surface brightness distribution, spurious variations in the abundance of heavy elements, changes in line spectral shapes and even polarization of line emission. The magnitude of these effects not only depends on the density, temperature and ionization state of the gas, but is also sensitive to the characteristics of the gas velocity field. This opens a possibility to use resonant scattering as a convenient and powerful tool to study IGM properties. We discuss the application of these effects to galaxy clusters.
Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity
International Nuclear Information System (INIS)
Here, we report the photon-plasmon interaction scheme and enhanced field strengths resulted into the amplification of phonon in a novel microcavity. A metal-dielectric microcavity, with unified cavity photonic mode and localized surface plasmon resonances, is visualized by impregnating the gold nanoparticles into the deep see-through nano-sized pores of porous silicon microcavity. The intense optical field strengths resulting from the photon-plasmon interactions are probed by both resonant and non-resonant Raman scattering experiments. Due to photon-plasmon-phonon interaction mechanism, several orders of enhancement in the intensity of scattered Raman Stokes photon (at 500 cm−1) are observed. Our metal nanoparticle-microcavity hybrid system shows the potential to improve the sensing figure of merit as well as the applications of plasmonics for optoelectronics, photovoltaics, and related technologies
Experimental investigation of the 12C+12C fusion at very low energies by direct and indirect methods
International Nuclear Information System (INIS)
The 12C+12C fusion reaction plays a crucial role during stellar evolution. The astrophysically important energy range spans from 1 MeV to 3 MeV. However, its cross section has not been determined with enough precision, despite numerous studies, due to the extremely low reaction cross sections and the large experimental background. To allow measurements of the 12C+12C fusion at astrophysical energies, we developed an efficient thick-target method using large-area silicon strip detectors. Further measurements at even lower energies will be performed using coincidences between a silicon-detector and a Ge-detector array, at the high-current accelerator under construction at the University of Notre Dame. Since the coincidence method does not allow obtaining information about the channels without gamma-ray emission, a solenoid spectrometer has been constructed for complementary measurements. Meanwhile, we are also investigating the 24Mg(α, α') reaction using the Grand Raiden Spectrometer at RCNP to search for potential resonances in the 12C+12C fusion reaction. Preliminary results from these measurements will be presented.
A Model of Resonance Scattering on Curved Quantum Wires
Exner, Pavel
A model of electron motion in a curved quantum wire of a finite length 2D attached to a pair of macroscopic electrodes is studied. Regarding the problem as a two-dimensional one, we model the electrodes as halfplanes and the quantum wire as a line segment joining them; it supports a potential which is a combination of a constant transversal-mode energy and an attractive curvature-induced term. We show that the bound states which may be present at an infinite quantum wire turn into resonances and that spectral concentration is valid as D .Translated AbstractEin Modell der Resonanzstreuung auf gekrümmten, dünnen DrähtenDas Modell einer Elektronenbewegung in einem gekrümmten, ultradünnen Draht der Länge 2D, der zwei makroskopische Elektroden verbindet, wird untersucht. Das Modell als zweidimensional betrachtend, nehmen wir die Elektroden als Halbebenen und den Draht als verbindendes Liniensegment. Das Potential ist eine Kombination aus konstanter Transversalmoden-energie und einem anziehenden, von der Krümmung hervorgerufenen Term. Wir zeigen, daß der gebundene Zustand, der im unendlich langen Draht auftreten kann, in Resonanzen übergeht, und die Spektraldichte für D gilt.
Papazoglou, S.; Hamhaber, U.; Braun, J.; Sack, I.
2007-02-01
A method based on magnetic resonance elastography is presented that allows measuring the weldedness of interfaces between soft tissue layers. The technique exploits the dependence of shear wave scattering at elastic interfaces on the frequency of vibration. Experiments were performed on gel phantoms including differently welded interfaces. Plane wave excitation parallel to the planar interface with corresponding motion sensitization enabled the observation of only shear-horizontal (SH) wave scattering. Spatio-temporal filtering was applied to calculate scattering coefficients from the amplitudes of the incident, transmitted and reflected SH-waves in the vicinity of the interface. The results illustrate that acoustic wave scattering in soft tissues is largely dependent on the connectivity of interfaces, which is potentially interesting for imaging tissue mechanics in medicine and biology.
Low-energy $DD^{*+}$ Scattering and the Resonance-like Structure $Z_c(3900)$
Chen, Ying; Lei, Yu-Hong; Li, Ning; Liang, Jian; Liu, Chuan; Liu, Hang; Liu, Jin-Long; Liu, Liuming; Liu, Yong-Fu; Liu, Yu-Bin; Liu, Zhaofeng; Ma, Jian-Ping; Wang, Zhan-Lin; Yang, Yi-Bo; Zhang, Jian-Bo
2014-01-01
In this exploratory lattice study, low-energy scattering of $D$ and $D^*$ meson are analyzed using lattice QCD with $N_f=2$ twisted mass fermion configurations with three pion mass values. The calculation is performed within single-channel L\\"uscher's finite-size formalism. The threshold scattering parameters, namely the scattering length $a_0$ and the effective range $r_0$, for the $s$-wave scattering in $J^P=1^+$ channel are extracted. For the cases in our study, the interaction between the two charmed mesons is weakly repulsive. Our lattice results therefore do not support the possibility of a shallow bound state for the two charmed mesons for the pion mass values we studied. This calculation provides some useful information on the nature of the newly discovered resonance-like structure $Z_c(3900)$ by various experimental groups.
Directional Fano Resonances at Light Scattering by a High Refractive Index Dielectric Sphere
Tribelsky, Michael I; Litman, Amelie; Eyraud, Christelle; Moreno, Fernando
2016-01-01
In this research, we report the experimental evidence of the directional Fano resonances at the scattering of a plane, linearly polarized electromagnetic wave by a homogeneous dielectric sphere with high refractive index and low losses. We observe a typical asymmetric Fano profile for the intensity scattered in, practically, any given direction, while the overall extinction cross section remains Lorentzian. The phenomenon is originated in the interference of the selectively excited electric dipolar and quadrupolar modes. The selectivity of the excitation is achieved by the proper choice of the frequency of the incident wave. Thanks to the scaling invariance of the Maxwell equations, in these experiments we mimic the scattering of the visible and near IR radiation by a nanoparticle made of common superconductor materials (Si, Ge, GaAs, GaP) by the equivalent scattering of a spherical particle of 18 mm in diameter in the microwave range. The theory developed to explain the experiments extends the conventional F...
International Nuclear Information System (INIS)
Inelastic scattering of 84 MeV/u 170 projectiles have been used to excite the giant resonances (GR) in various nuclei ranging from A=60 to A=232. For the isoscalar giant quadrupole resonance (ISGQR), the energy and width of the resonance, as well as the EWSR obtained from the measured cross sections, are in agreement with the known systematics for A>40. The observed GMR strengths are close to 100% EWRS and are consistent with other recent experimental results using heavy ion projectiles. These results lead to a somewhat different picture than that provided by previous studies using light projectiles. Strength is also observed at high excitation energy. The analysis of these resonances is in progress. Our study of the fission decay of GR in 232 Th leads to a somewhat different conclusion than previously deduced from data obtained with light ion projectiles, where no evidence for the fission decay of the ISGQR has been found. In the present work, due to the very good peak-to-continuum ratio, a structure is observed in the fission coincidence spectrum around 10 MeV which can be attributed to the fission decay of giant resonances. The measured fission probability is consistent with a statistical decay of the ISGQR. 10 figs
Valence neutrons' role in the collisions 13C+12C and 13C+13C
International Nuclear Information System (INIS)
The resonant behaviour is not limited to collisions between α-like nuclei: resonance structures have been observed in the direct channels for the 13C+12C and 13C+13C collisions; in the contrary, the resonances observed in the fusion channels are not so pronounced as in the 12C+12C case: the valence neutrons increase the number of reaction channels and the density of states in the states in the compound nuclei, the resonances are therefore 'washed out' and it is difficult to observe them experimentally
International Nuclear Information System (INIS)
Flux-averaged and flux-integrated cross sections for quasi-elastic neutrino charged-current scattering on nuclei are analyzed. It is shown that the flux-integrated differential cross sections are less dependent on nuclear models than the flux-averaged ones. We calculate these cross sections using the relativistic distorted-wave impulse approximation and relativistic Fermi gas model with the Booster Neutrino Beamline flux and compare the results with the recent MiniBooNE experimental data. Within these models an axial mass MA is extracted from a fit of the measured dσ/dQ2 cross section. The extracted value of MA=1.37±0.05 GeV/c2 is consistent with the MiniBooNE result. While the measured and calculated double differential cross sections dσ/dTdcosθ generally agree, the Fermi gas model predictions are typically lower than data at low muon energies and scattering angles.
Δ33 resonance in pion nucleus elastic, single, and double charge exchange scattering
International Nuclear Information System (INIS)
The Δ33 resonance is strongly excited in pion-nucleon scattering, but there is clearly only a limited amount of information that can be learned in scattering the pion from an isolated nucleon. One learns that there is a resonance of mass 1232 MeV, width 115 MeV, and, if one is willing to introduce a dynamical model, something about the off-shell extension of the amplitude. One stands to learn much more from pion-nucleus scattering because in this case the Δ33 resonance has an opportunity to scatter from nucleons, and how this occurs is not well understood. What do we know about the Δ-N interaction for pion-nucleus scattering. The isobar-hole model was invented to deal directly with the Δ33-nucleus dynamics, and a phenomenological determination of the isobar shell-model potential was attempted. The unknown dynamics deltaU/sub Δ/ is contained in a central isoscalar spreading potential of strength W0 and a spin orbit potential deltaU0 = W0rho + spin-orbit. The real part of W0rho is measured relative to the nucleon-nucleus potential. From a more theoretical point of view, one would like to be able to calculate deltaU/sub Δ/, including its isospin dependence, from an underlying dynamical model which is formulated in terms of the basic effective meson-baryon couplings. Some salient properties of these couplings can be determined from models of quark-bag structure, which raises the exciting possibility of learning about these fundamental issues from pion scattering. Attempts at Los Alamos to build a theoretical framework to deal with these and other issues are described
Non-resonant Mie scattering: Emergent optical properties of core-shell polymer nanowires
Khudiyev, Tural; Huseyinoglu, Ersin; Bayindir, Mehmet
2014-04-01
We provide the in-depth characterization of light-polymer nanowire interactions in the context of an effective Mie scattering regime associated with low refractive index materials. Properties of this regime sharply contrast with these of resonant Mie scattering, and involve the formation of strictly forward-scattered and coupling-free optical fields in the vicinity of core-shell polymer nanowires. Scattering from these optical fields is shown to be non-resonant in nature and independent from incident polarization. In order to demonstrate the potential utility of this scattering regime in one-dimensional (1D) polymeric nanostructures, we fabricate polycarbonate (PC) - polyvinylidene difluoride (PVDF) core-shell nanowires using a novel iterative thermal drawing process that yields uniform and indefinitely long core-shell nanostructures. These nanowires are successfully engineered for novel nanophotonics applications, including size-dependent structural coloration, efficient light capture on thin-film solar cells, optical nano-sensors with ultrahigh sensitivity and a mask-free photolithography method suitable for the straightforward production of 1D nanopatterns.
Braicovich, L; Dellea, G; Tacon, M Le; Sala, M Moretti; Morawe, C; Peffen, J-Ch; Supruangnet, R; Yakhou, F; Ghiringhelli, G; Brookes, N B
2014-01-01
Resonant Inelastic X-ray Scattering (RIXS) in the soft x-ray range is an element-specific energy-loss spectroscopy used to probe the electronic and magnetic excitations in strongly correlated solids. In the recent years, RIXS has been progressing very quickly in terms of energy resolution and understanding of the experimental results, but the interpretation of spectra could further improve, sometimes decisively, from a full knowledge of the polarization of incident and scattered photons. Here we present the first implementation, in a high resolution RIXS spectrometer used to analyze the scattered radiation, of a device allowing the measurement of the degree of linear polarization. The system, based on a graded W/B4C multilayer mirror installed in proximity of the CCD detector, has been installed on the AXES spectrometer at the ESRF; it has been fully characterized and it has been used for a demonstration experiment at the Cu L3 edge on a high-Tc superconducting cuprate. The loss in efficiency suffered by the ...
Energy Technology Data Exchange (ETDEWEB)
Braicovich, L., E-mail: lucio.braicovich@polimi.it; Minola, M.; Dellea, G.; Ghiringhelli, G. [CNR-SPIN and Dipartimento di Fisica, Politecnico di Milano, piazza Leonardo Da Vinci 32, Milano I-20133 (Italy); Le Tacon, M. [Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany); Moretti Sala, M.; Morawe, C.; Peffen, J.-Ch.; Yakhou, F.; Brookes, N. B. [European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble F-38043 (France); Supruangnet, R. [Synchrotron Light Research Institute, Nakhon Ratchasima (Thailand)
2014-11-15
Resonant Inelastic X-ray Scattering (RIXS) in the soft x-ray range is an element-specific energy-loss spectroscopy used to probe the electronic and magnetic excitations in strongly correlated solids. In the recent years, RIXS has been progressing very quickly in terms of energy resolution and understanding of the experimental results, but the interpretation of spectra could further improve, sometimes decisively, from a full knowledge of the polarization of incident and scattered photons. Here we present the first implementation, in a high resolution soft-RIXS spectrometer used to analyze the scattered radiation, of a device allowing the measurement of the degree of linear polarization. The system, based on a graded W/B{sub 4}C multilayer mirror installed in proximity of the CCD detector, has been installed on the AXES spectrometer at the ESRF (European Synchrotron Radiation Facility); it has been fully characterized and it has been used for a demonstration experiment at the Cu L{sub 3} edge on a high-T{sub c} superconducting cuprate. The loss in efficiency suffered by the spectrometer equipped with this test facility was a factor 17.5. We propose also a more advanced version, suitable for a routine use on the next generation of RIXS spectrometers and with an overall efficiency up to 10%.
One phonon resonant Raman scattering in semiconductor quantum wires: Magnetic field effect
Energy Technology Data Exchange (ETDEWEB)
Betancourt-Riera, Re., E-mail: rbriera@posgrado.cifus.uson.mx [Instituto Tecnologico de Hermosillo, Avenida Tecnologico S/N, Colonia Sahuaro, C.P. 83170, Hermosillo, Sonor, (Mexico); Departamento de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, C.P. 83190, Hermosillo, Sonora (Mexico); Betancourt-Riera, Ri. [Instituto Tecnologico de Hermosillo, Avenida Tecnologico S/N, Colonia Sahuaro, C.P. 83170, Hermosillo, Sonora (Mexico); Nieto Jalil, J.M. [Tecnologico de Monterrey-Campus Sonora Norte, Bulevar Enrique Mazon Lopez No. 965, C.P. 83000, Hermosillo, Sonora (Mexico); Riera, R. [Departamento de Investigacion en Fisica, Universidad de Sonora, Apartado Postal 5-088, C.P. 83190, Hermosillo, Sonora (Mexico)
2013-02-01
We have developed a theory of one phonon resonant Raman scattering in a semiconductor quantum wire of cylindrical geometry in the presence of an external magnetic field distribution, parallel to the cylinder axis. The effect of the magnetic field in the electron and hole states, and in the Raman scattering efficiency, is determinate. We consider the electron-phonon interaction using a Froehlich-type Hamiltonian, deduced for the case of complete confinement phonon modes by Comas and his collaborators. We also assume T=0 K, a single parabolic conduction and valence bands. The spectra are discussed for different magnetic field values and the selection rules for the processes are also studied.
Asano, Motoki; Özdemir, Şahin Kaya; Ikuta, Rikizo; Yang, Lan; Imoto, Nobuyuki; Yamamoto, Takashi
2016-01-01
We report the first observation of stimulated Brillouin scattering (SBS) with Brillouin lasing, and Brillouin-coupled four-wave-mixing (FWM) in an ultra-high-Q silica microbottle resonator. The Brillouin lasing was observed at the frequency of $\\Omega_B=2\\pi\\times10.4$ GHz with a threshold power of $0.45$ mW. Coupling between Brillouin and FWM was observed in both backward and forward scattering directions with separations of $2\\Omega_B$. At a pump power of $10$ mW, FWM spacing reached to 7th and 9th order anti-Stokes and Stokes, respectively.
DEFF Research Database (Denmark)
de Lasson, Jakob Rosenkrantz; Kristensen, Philip Trøst; Mørk, Jesper
2012-01-01
We present a multiple-scattering formalism for simulating scattering of electromagnetic waves on spherical inhomogeneities in 3D. The formalism is based on the Lippmann-Schwinger equation and the electromagnetic Green's tensor and applies an expansion of the electric field on spherical wavefuncti...... wavefunctions. As an example, we analyze localized surface plasmons in chains of Ag spheres, and show how the resonances of such systems depend sensitively on the polarization of the incoming field, the spacing between the particles and the number of particles in the chain....
Resonant Rayleigh scattering of exciton-polaritons in multiple quantum wells
DEFF Research Database (Denmark)
Malpuech, Guillaume; Kavokin, Alexey; Langbein, Wolfgang Werner;
2000-01-01
A theoretical concept of resonant Rayleigh scattering (RRS) of exciton-polaritons in multiple quantum wells (QWs) is presented. The optical coupling between excitons in different QWs can strongly affect the RRS dynamics, giving rise to characteristic temporal oscillations on a picosecond scale....... Bragg and anti-Bragg arranged QW structures with the same excitonic parameters are predicted to have drastically different RRS spectra. Experimental data on the RRS from multiple QWs show the predicted strong temporal oscillations at small scattering angles, which are well explained by the presented...... theory....
Roca, L
2012-01-01
We present a way to evaluate the scattering of unstable particles quantized in a finite volume with the aim of extracting physical observables for infinite volume from lattice data. We illustrate the method with the $\\pi\\rho$ scattering which generates dynamically the axial-vector $a_1(1260)$ resonance. Energy levels in a finite box are evaluated both considering the $\\rho$ as a stable and unstable resonance and we find significant differences between both cases. We discuss how to solve the problem to get the physical scattering amplitudes in the infinite volume, and hence phase shifts, from possible lattice results on energy levels quantized inside a finite box.
Resonance scattering in the X-ray emission lines profiles of ζ Puppis
Leutenegger, M. A.; Cohen, D. H.; Kahn, S. M.; Owocki, S. P.; Paerels, F. B. S.
2008-01-01
We present XMM-Newton Reflection Grating Spectrometer observations of pairs of X-ray emission line profiles from the O star ζ Pup that originate from the same He-like ion. The two profiles in each pair have different shapes and cannot both be consistently fit by models assuming the same wind parameters. We show that the differences in profile shape can be accounted for in a model including the effects of resonance scattering, which affects the resonance line in the pair but not the intercombi...
Resonance scattering in the X-ray emission line profiles of Zeta Puppis
Leutenegger, M. A.; Cohen, D. H.; Kahn, S. M.; Owocki, S. P.; Paerels, F. B. S.
2007-01-01
We present XMM-Newton Reflection Grating Spectrometer observations of pairs of X-ray emission line profiles from the O star Zeta Pup that originate from the same He-like ion. The two profiles in each pair have different shapes and cannot both be consistently fit by models assuming the same wind parameters. We show that the differences in profile shape can be accounted for in a model including the effects of resonance scattering, which affects the resonance line in the pair but not the interco...
Evidence for a scalar $\\kappa(900)$ resonance in $\\pi$-K scattering
Black, D; Sannino, F; Schechter, J
1998-01-01
Motivated by the $1/N_c$ expansion, we study a simple model in which the pi-K scattering amplitude is the sum of a current-algebra contact term and resonance pole exchanges. This phenomenological model is crossing symmetric and, when a putative light strange scalar meson, kappa, is included, satisfies the unitarity bounds to well above 1 GeV. The model also features chiral dynamics, vector meson dominance and appropriate interference between the established scalar K*(1430) resonance and its predicted background. We briefly discuss the physical significance of the results and directions for further work.
Collision times in pi-pi and pi-K scattering and spectroscopy of meson resonances
Kelkar, N G; Khemchandani, K P
2003-01-01
Using the concept of collision time (time delay) introduced by Eisenbud and Wigner and its connection to on-shell intermediate unstable states, we study mesonic resonances in pi-pi and pi-K scattering. The time-delay method proves its usefulness by revealing the spectrum of the well-known rho- and K*-mesons and by supporting some speculations on rho-mesons in the 1200 MeV region. We use this method further to shed some light on more speculative meson resonances, among others the enigmatic scalars. We confirm the existence of chiralons below 1 GeV in the unflavoured and strange meson sector.
Forward dispersion relations for pion-kaon scattering and the K*0(800) resonance
Rodas, A
2016-01-01
We review our recent analysis of $\\pi K$ scattering data in terms of forward dispersion relations, and also present the parameters of the strange resonances. This work consists of fits to the data that are constrained to satisfy analyticity requirements. The method yields a set of simple and consistent parameterizations that are compatible with forward dispersion relations up to 1.6 GeV while still describing the data. We also obtain the pole parameters of the $K^*_0(800)$ and the $K^*(892)$ resonances.
A DNA biosensor based on resonance light scattering using unmodified gold bipyramids
International Nuclear Information System (INIS)
We report on a novel biosensor for determining sequence-specific DNA. It is based on resonance light scattering (RLS) caused by the aggregation of gold bipyramids. These display localized surface plasmon resonance and can be used as a bioprobe. The absorption spectra and the transmission electron micrographs provide visual evidence of the aggregation of the gold bipyramids in the presence of DNA. The RLS intensity of the gold bipyramids increases with the concentration of the target DNA. The method was successfully applied to the determination of a 30-mer single-stranded oligonucleotide and works over the 0.1-10 nM concentration range. (author)
Nunes, A.; Zanetti, F. M.; Lyra, M. L.
2016-10-01
In this work, we study the transmission characteristics of a two-channels coupler model system using the Boundary Wall Method (BWM) to determine the solution of the corresponding scattering problem of an incident plane wave. We show that the BWM provides detailed information regarding the transmission resonances. In particular, we focus on the case of single channel input aiming to explore the energy switching performance of the coupler. We show that the coupler geometry can be tailored to allow for the first transmission resonances to be predominantly transmitted on specific output channels, an important characteristic for the realization of logical operations.
Ferrari, Eugenio; Spezzani, Carlo; Fortuna, Franck; Delaunay, Renaud; Vidal, Franck; Nikolov, Ivaylo; Cinquegrana, Paolo; Diviacco, Bruno; Gauthier, David; Penco, Giuseppe; Ribič, Primož Rebernik; Roussel, Eleonore; Trovò, Marco; Moussy, Jean-Baptiste; Pincelli, Tommaso; Lounis, Lounès; Manfredda, Michele; Pedersoli, Emanuele; Capotondi, Flavio; Svetina, Cristian; Mahne, Nicola; Zangrando, Marco; Raimondi, Lorenzo; Demidovich, Alexander; Giannessi, Luca; de Ninno, Giovanni; Danailov, Miltcho Boyanov; Allaria, Enrico; Sacchi, Maurizio
2016-01-01
The advent of free-electron laser (FEL) sources delivering two synchronized pulses of different wavelengths (or colours) has made available a whole range of novel pump-probe experiments. This communication describes a major step forward using a new configuration of the FERMI FEL-seeded source to deliver two pulses with different wavelengths, each tunable independently over a broad spectral range with adjustable time delay. The FEL scheme makes use of two seed laser beams of different wavelengths and of a split radiator section to generate two extreme ultraviolet pulses from distinct portions of the same electron bunch. The tunability range of this new two-colour source meets the requirements of double-resonant FEL pump/FEL probe time-resolved studies. We demonstrate its performance in a proof-of-principle magnetic scattering experiment in Fe-Ni compounds, by tuning the FEL wavelengths to the Fe and Ni 3p resonances.
Ferrari, Eugenio; Spezzani, Carlo; Fortuna, Franck; Delaunay, Renaud; Vidal, Franck; Nikolov, Ivaylo; Cinquegrana, Paolo; Diviacco, Bruno; Gauthier, David; Penco, Giuseppe; Ribič, Primož Rebernik; Roussel, Eleonore; Trovò, Marco; Moussy, Jean-Baptiste; Pincelli, Tommaso; Lounis, Lounès; Manfredda, Michele; Pedersoli, Emanuele; Capotondi, Flavio; Svetina, Cristian; Mahne, Nicola; Zangrando, Marco; Raimondi, Lorenzo; Demidovich, Alexander; Giannessi, Luca; De Ninno, Giovanni; Danailov, Miltcho Boyanov; Allaria, Enrico; Sacchi, Maurizio
2016-01-01
The advent of free-electron laser (FEL) sources delivering two synchronized pulses of different wavelengths (or colours) has made available a whole range of novel pump–probe experiments. This communication describes a major step forward using a new configuration of the FERMI FEL-seeded source to deliver two pulses with different wavelengths, each tunable independently over a broad spectral range with adjustable time delay. The FEL scheme makes use of two seed laser beams of different wavelengths and of a split radiator section to generate two extreme ultraviolet pulses from distinct portions of the same electron bunch. The tunability range of this new two-colour source meets the requirements of double-resonant FEL pump/FEL probe time-resolved studies. We demonstrate its performance in a proof-of-principle magnetic scattering experiment in Fe–Ni compounds, by tuning the FEL wavelengths to the Fe and Ni 3p resonances. PMID:26757813
X-ray resonance scattering in a spherically symmetric coronal model
Haisch, B. M.; Claflin, E. S.
1985-01-01
In the solar corona the opacities of some of the prominent X-ray emission lines are on the order of tau of about I over typical coronal path lengths. A particular solution of the radiative transfer problem involving an extended, spherically symmetric coronal shell radiating isotropic, homogeneous emission in which single-scattering also takes place is presented and discussed. Within the context of this simplified model, it is found that scattered radiation is an important contribution to the total emergent resonance line flux and that for the He-like family of resonance (r), intercombination (i), and forbidden (f) lines, the ratio G = (f + i)/r would decrease as a function of optical depth for disk-center emission in an extended spherically symmetric corona.
Liu, Xiaoling; Yuan, Hong; Pang, Daiwen; Cai, Ruxiu
2004-01-01
In this paper, we used resonance light scattering (RLS) spectroscopy to study the interaction between thiol-containing pharmaceutical-thiamazole and gold colloid. At pH 5.2, the resonance light scattering spectrum of gold nanoparticles has a maximum peak at 555 nm and the RLS intensity is enhanced by trace amount of thiamazole due to the interaction between thiamazole and gold colloid. The binding of colloidal gold to thiamazole results in ligand-induced aggregation of colloidal gold, which was characterized by RLS spectrum, ultraviolet-visible (UV-Vis) spectrum, and transmission electron microscopy (TEM). Based upon the study, we proposed a highly sensitive, gold colloid-based assay using RLS spectrum to detect pharmaceuticals for the first time. The mechanism of binding interaction between Au colloid and thiamazole was also discussed.
Resonance Light Scattering Spectra of Silver Thiocyanate System and its Application in Analysis
Institute of Scientific and Technical Information of China (English)
Chang Yin LU; Zhi Hui HAN; Sheng Yuan YANG
2005-01-01
A novel determination method of Ag+ was established. In acetic acid-sodium acetate buffer (pH 5.0) medium, Ag+ reacts with SCN- to form AgSCN in the presence of TritonX-100,which results in an increase of resonance light scattering (RLS) and giving a new RLS spectrum.The maximum RLS peak was at 585 nm. The enhancement of resonance light scattering at 585nm was proportional to the concentration of Ag+ ranging from 0.0045-4.00 μg mL-1 (r=0.9991),and the detection limit was 1.37 ng mL-1 with the recovery of 97.70%～104.80%.
We intend to measure the structure of the unbound nucleus $^{21}$Al via resonance elastic and inelastic scattering with an active target. There are many goals: \\\\ a) to locate the 1/2$^{+}$ level in $^{21}$Al that brings information on the Thomas-Ehrman shift, \\\\ b) to measure the energy spectrum of $^{21}$Al which is a N=8 isotone with the resonance elastic scattering reaction, \\\\ c) to investigate via inelastic scattering the strength of core excitations in the existence of narrow unbound resonances beyond the proton drip-line.
Importance of resonance widths in low-energy scattering of weakly-bound light-mass nuclei
Fraser, P R; Amos, K; Bray, I; Canton, L; Fossion, R; Kadyrov, A S; Karataglidis, S; Svenne, J P; van der Knijff, D
2016-01-01
What effect do particle-emitting resonances have on the scattering cross section? What physical considerations are necessary when modelling these resonances? These questions are important when theoretically describing scattering experiments with radioactive ion beams which investigate the frontiers of the table of nuclides, far from stability. Herein, a novel method is developed that describes resonant nuclear scattering from which centroids and widths in the compound nucleus are obtained when one of the interacting bodies has particle unstable resonances. The method gives cross sections without unphysical behavior that is found if simple Lorentzian forms are used to describe resonant target states. The resultant cross sections differ significantly from those obtained when the states in the coupled channel calculations are taken to have zero width, and compound-system resonances are better matched to observed values.
Sub-coulombian fusion of 12 C + 12 C measured with the γ rays improved technique
International Nuclear Information System (INIS)
In this work we report the measurements carried out in the National Institute of Nuclear Research of Mexico (ININ) for the absolute section of fusion of the system 12 C + 12 C in an interval of energy of Ec.m. 4.5-6.5 MeV with fine steps of 75 keV. The objective of measuring in fine steps is to register all the existent resonances. To be able to obtain an absolute normalization of the cross section, it was applied a method that allows to measure simultaneously the one number of projectiles that arrive to the target, as well as the numbers of nuclei in the target, even when this doesn't stay constant. In the chapter 2 the experimental procedure it is described, it is carried out with detail the analysis of the data and the results are shown. Later on the chapter 3 it is described with detail the method used for the absolute normalization, that is to say the form of obtaining the quantities Np and ηT of the equation is explained and the obtained results are presented. Additionally in the chapter 4 it was carried out a theoretical analysis applying models as that of barrier penetration and the optical model combined with the Breit-Wigner theory with the purpose of being able to reproduce the resonances of the excitation function. In the chapter 5 the concept of S-Astrophysicist factor it is introduced and this value is calculated for our data. Finally in the chapter 6 the conclusions of this work are presented. (Author)
Schwarm, F -W; Falkner, S; Pottschmidt, K; Wolff, M T; Becker, P A; Sokolova-Lapa, E; Klochkov, D; Ferrigno, C; Fuerst, F; Hemphill, P B; Marcu-Cheatham, D M; Dauser, T; Wilms, J
2016-01-01
Electron cyclotron resonant scattering features (CRSFs) are observed as absorption-like lines in the spectra of X-ray pulsars. A significant fraction of the computing time for Monte Carlo simulations of these quantum mechanical features is spent on the calculation of the mean free path for each individual photon before scattering, since it involves a complex numerical integration over the scattering cross section and the (thermal) velocity distribution of the scattering electrons. We aim to numerically calculate interpolation tables which can be used in CRSF simulations to sample the mean free path of the scattering photon and the momentum of the scattering electron. The tables also contain all the information required for sampling the scattering electron's final spin. The tables were calculated using an adaptive Simpson integration scheme. The energy and angle grids were refined until a prescribed accuracy is reached. The tables are used by our simulation code to produce artificial CRSF spectra. The electron...
REX: A Monte Carlo simulation of thick gas target resonant scattering reactions
Energy Technology Data Exchange (ETDEWEB)
Curtis, N., E-mail: n.curtis@bham.ac.uk; Walshe, J.
2015-10-11
A Monte Carlo code has been developed to simulate resonant scattering reactions using the thick gas target technique in inverse kinematics. Results are presented for the {sup 4}He({sup 20}Ne,α){sup 20}Ne reaction at 70 MeV, and compared to an experimental measurement which utilised an array of segmented silicon strip detectors. In the case studied, angular straggling in the chamber window is found to dominate the excitation energy resolution.
Microscopic theory of resonant soft x-ray scattering in systems with charge order
Benjamin, David Isaiah; Abanin, Dmitry; Abbamonte, Peter; Demler, Eugene A.
2012-01-01
We present a microscopic theory of resonant soft-x-ray scattering that accounts for the delocalized character of valence electrons. Unlike past approaches based on local form factors, our functional determinant method treats realistic band structures. This method builds upon earlier theoretical work in mesoscopic physics and accounts for excitonic effects as well as the orthogonality catastrophe arising from interaction between the core hole and the valence band electrons. We show that the tw...
Spin degrees of freedom in electron nucleon scattering in the resonance region
International Nuclear Information System (INIS)
Some aspects of using polarized electrons and/or polarized targets in electron-nucleon scattering experiments are discussed. Polarization measurements can be used to extend the knowledge of nucleon form-factor measurements to higher Q2 and are indispensable for a model-independent extraction of the helicity amplitudes of exclusive meson production. Measurements of polarization asymmetries may also help in revealing the excitation of weaker resonances
Direct probe of anisotropy in atom-molecule collisions via quantum scattering resonances
Klein, Ayelet; Shagam, Yuval; Skomorowski, Wojciech; Żuchowski, Piotr. S.; Pawlak, Mariusz; Janssen, Liesbeth M. C.; Moiseyev, Nimrod; van de Meerakker, Sebastiaan Y. T.; van der Avoird, Ad; Koch, Christiane P.; Narevicius, Edvardas
2016-01-01
Anisotropy is a fundamental property of particle interactions. It occupies a central role in cold and ultra-cold molecular processes, where long range forces have been found to significantly depend on orientation in ultra-cold polar molecule collisions. Recent experiments have demonstrated the emergence of quantum phenomena such as scattering resonances in the cold collisions regime due to quantization of the intermolecular degrees of freedom. Although these states have been shown to be sensi...
Institute of Scientific and Technical Information of China (English)
TANG XiaoLing; LIU ZhongFang; LIU ShaoPu; HU XiaoLi
2007-01-01
In pH 4.5 Britton-Robinson (BR) buffer solution, erythrosin (ET) can react with diphenhydramine (DP) to form a 1:1 ion-association complex, which not only results in the change of the absorption spectra, but also results in the great enhancement of resonance Rayleigh scattering (RRS) and the quenching of fluorescence. Furthermore, a new RRS spectrum will appear, and the maximum RRS wavelength was located at about 580 nm.In this work, the spectral characteristics of the absorption, fluorescence and RRS, the optimum conditions of the reaction and the properties of an analytical chemistry were investigated. A sensitive, simple and new method for the determination of DP by using erythrosin as a probe has been developed. The detection limits for DP were 0.0020 μg/mL for RRS method, 0.088 μg/mL for absorption method and 0.094 μg/mL for fluorophotometry. There was a linear relationship between the absorbance, RRS and fluorescence intensities and the drug concentration in the range of 0.0067-2.0, 0.29-6.4 and 0.31-3.2 μg/mL, respectively. The effects of the interaction of diphenhydramine and erythrosin on the absorption, fluorescence and resonance Rayleigh scattering spectra were discussed. In light polarization experiment, the polarization of RRS at maximum wavelength was measured to be P = 0.9779, and it revealed that the RRS spectrum of DP-ET complex consists mostly of resonance scattering and few resonance fluorescence. In this study, enthalpy of formation and mean polarizability were calculated by AM1 quantum chemistry method. In addition, the reaction mechanism and the reasons for the enhancement of scattering spectra and the energy transfer between absorption, fluorescence and RRS were discussed.
Measuring velocity of sound with nuclear resonant inelastic x-ray scattering
Hu, Michael Y.; Sturhahn, Wolfgang; Toellner, Thomas S.; Mannheim, Philip D.; Brown, Dennis E.; Zhao, Jiyong; Alp, E. Ercan
2002-01-01
Nuclear resonant inelastic x-ray scattering is used to measure the projected partial phonon density of states of materials. A relationship is derived between the low-energy part of this frequency distribution function and the sound velocity of materials. Our derivation is valid for harmonic solids with Debye-like low-frequency dynamics. This method of sound velocity determination is applied to elemental, composite, and impurity samples which are representative of a wide variety of both crysta...
Alpha clustering in Ti isotopes: 40,44,48Ca + α resonant scattering
Directory of Open Access Journals (Sweden)
Bailey Sam
2016-01-01
Full Text Available Measurements were made of the 4He(40,44,48Ca,α resonant scattering reactions at 180° and up to Ec.m. ~ 11.5MeV, using the Thick Target Inverse Kinematics technique. These measurements are discussed, with a focus on assessing their usefulness for investigating α-clustering in medium mass 44,48,52Ti nuclei.
Choi, M S; Lee, S H
1999-01-01
The inherent background coefficients that exactly describe the background amplitudes in the scattered field have been presented for the scattering of plane acoustic waves by a system of concentrically multilayered solid and/or fluid shells submerged in a fluid. The coefficients have been obtained by replacing the mechanical surface admittance function with the zero-frequency limit of the admittance function for the analogous fluid system, where the shear wave speeds in the solid layers are set to zero. By taking advantage of the concept of incoming and outgoing waves, we find the surface admittance function for the fluid system in such a form that the analytical generalization for any number of layers and the physical interpretation are very easy. The background coefficients obtained are independent of the bulk wave speeds in the system: they depend on the mass densities and the thickness of the shells. With increasing frequency, the inherent background undergoes a transition from the soft to the rigid backgr...
Resonant elastic X-ray scattering in chemistry and materials science
Helliwell, J. R.; Helliwell, M.; Kaucic, V.; Logar, N. Z.
2012-06-01
The applications of anomalous scattering for locating metal atoms and discriminating between different elements has increased when optimised with synchrotron X-radiation.The on-resonance effect enhances the targeted elemental signal and allows small occupancies to be determined, including in situations of a mixed metal population at a single atomic site. Thus the applications of resonant elastic X-ray scattering in biological, inorganic and materials chemistry is being widely applied to single crystals, which is our emphasis, but also powders, fibres, solutions, amorphous and thin film states of matter. Recent developments have included the use of high photon energies (upto 100 keV) as well as softer X-rays (2 keV). The various instrument and technical capabilities have improved in the last 15 years. This ease of measurement of the resonant scattering signals along with absorption edge shifts indicates an expansion to the measurement of multiple data sets, to allow monitoring of redox changes. Whilst crystal structure determination in biological crystallography has been revolutionised by the MAD method, it is not a requirement for chemical or materials crystallography, as other phasing techniques are routine. Synchrotron source upgrades will allow nano-sized X-ray beams to be more widely available. The new X-ray lasers suggest new capabilities too.
Resonance Raman scattering and excitonic spectra in TlInS{sub 2} crystals
Energy Technology Data Exchange (ETDEWEB)
Zalamai, V.V. [Institute of Applied Physics, Academy of Sciences of Moldova, 5 Academy Street, 2028 Chisinau, Republic of Moldova (Moldova, Republic of); Stamov, I.G. [T.G. Shevchenko State University of Pridnestrovie, 25 Oktyabrya Street 107, 3300 Tiraspol, Republic of Moldova (Moldova, Republic of); Syrbu, N.N., E-mail: sirbunn@yahoo.com [Technical University of Moldova, 168 Stefan cel Mare Avenue, 2004 Chisinau, Republic of Moldova (Moldova, Republic of); Ursaki, V.V. [Institute of Applied Physics, Academy of Sciences of Moldova, 5 Academy Street, 2028 Chisinau, Republic of Moldova (Moldova, Republic of); Dorogan, V. [Technical University of Moldova, 168 Stefan cel Mare Avenue, 2004 Chisinau, Republic of Moldova (Moldova, Republic of)
2015-04-15
The excitons ground and excited states for E∥a and E∥b polarizations in absorption and reflection spectra of TlInS{sub 2} crystals were detected. The fundamental parameters of excitons and bands were determined at k=0. The resonance Raman spectra were investigated in the region of excitons transitions. The resonance Raman scattering spectra with participation of optical phonons that are active at the center of Brillouin zone were identified. The Raman scattering in Y(YX)Z and Y(ZX)Z geometries at 10 K with excitation by He–Ne laser was researched. Energies of phonons with A{sub g} and B{sub g} symmetries were determined. It was shown that the number of modes at 10 K was two times lower than expected according to theoretical calculations. - Highlights: • The resonance Raman scattering in geometry Y(YX)Z and Y(ZX)Z at 10 K was investigated. • Energies of phonons with A{sub g} and B{sub g} symmetries were determined. • The experimental and theoretical calculations completely conform if crystals are described by symmetry group D{sub 4h}{sup 15}. • The main parameters of excitons and bands were determined. • The model of electron transitions in k=0 was suggested.
Diffuse Surface Scattering in the Plasmonic Resonances of Ultra-Low Electron Density Nanospheres
Monreal, R Carmina; Apell, S Peter
2015-01-01
Localized surface plasmon resonances (LSPRs) have recently been identified in extremely diluted electron systems obtained by doping semiconductor quantum dots. Here we investigate the role that different surface effects, namely electronic spill-out and diffuse surface scattering, play in the optical properties of these ultra-low electron density nanosystems. Diffuse scattering originates from imperfections or roughness at a microscopic scale on the surface. Using an electromagnetic theory that describes this mechanism in conjunction with a dielectric function including the quantum size effect, we find that the LSPRs show an oscillatory behavior both in position and width for large particles and a strong blueshift in energy and an increased width for smaller radii, consistent with recent experimental results for photodoped ZnO nanocrystals. We thus show that the commonly ignored process of diffuse surface scattering is a more important mechanism affecting the plasmonic properties of ultra-low electron density ...
Institute of Scientific and Technical Information of China (English)
DUAN Hui; LIU Zhong-Fang; LIU Shao-Pu; KONG Ling
2008-01-01
Heated in a boiling water bath, penicillin antibiotics such as amoxicillin, ampicillin, sodium cloxacillin, sodium carbenicillin and sodium benzylpenicillin could react with K3[Fe(CN)6] to form combined products in a dilute HCl medium.As a result, resonance Rayleigh scattering (RRS) intensity was enhanced greatly and new RRS spectra appeared.The maximum scattering wavelengths of the five combined products are all located at 330 nm.The scattered intensity increments (△I) of the combined products are directly proportional to the concentrations of the antibiotics in a certain range.The methods exhibit high sensitivity, and the detection limits for the five penicillin antibiotics are between 4.61 and 5.62 ng·mL-1.The spectral characteristics of RRS and the optimum reaction conditions were investigated.The mechanism of reaction and the reasons for the enhancement of resonance light scattering were discussed.The effects of coexisting substances have been examined, and the results indicated that the method had a good selectivity.It can be applied to the determination of penicillin antibiotics in capsule, tablet, human serum and urine samples.
An Effective Math Model for Eliminating Interior Resonance Problems of EM Scattering
Directory of Open Access Journals (Sweden)
Zhang Yun-feng
2015-01-01
Full Text Available It is well-known that if an E-field integral equation or an H-field integral equation is applied alone in analysis of EM scattering from a conducting body, the solution to the equation will be either nonunique or unstable at the vicinity of a certain interior frequency. An effective math model is presented here, providing an easy way to deal with this situation. At the interior resonant frequencies, the surface current density is divided into two parts: an induced surface current caused by the incident field and a resonance surface current associated with the interior resonance mode. In this paper, the presented model, based on electric field integral equation and orthogonal modal theory, is used here to filter out resonant mode; therefore, unique and stable solution will be obtained. The proposed method possesses the merits of clarity in concept and simplicity in computation. A good agreement is achieved between the calculated results and those obtained by other methods in both 2D and 3D EM scattering.
Liu, Z. Z.; Zhang, Q.; Xiao, J. J.
2016-01-01
We study the optical properties associated with both the polariton gap and the Bragg gap in periodic resonator-waveguide coupled systems, based on the temporal coupled mode theory and the transfer matrix method. Using the complex band and the transmission spectrum, it is feasible to tune the interaction between multiple Bragg scattering and local resonance, which may give rise to analogous phenomena of electromagnetically induced transparency (EIT). We further design a plasmonic slot waveguide side-coupled with local plasmonic resonators to demonstrate the EIT-like effects in the near-infrared band. Numerical calculations show that realistic amounts of metal Joule loss may destroy the interference and the total absorption is enhanced in the transparency window due to the near zero group velocity of the guiding wave.
Scattering properties of vein induced localized surface plasmon resonances on a gold disk
Amin, Muhammad
2011-12-01
It is demonstrated via simulations that a gold nano-disk with a non-concentric cavity supports localized surface plasmon resonances over a frequency band that includes the visible and the near-infrared parts of the spectrum. The charge distribution on the disk indicates that the two distinct peaks in the scattering cross section are due to the (hybridized) higher-order plasmon modes; plasmon hybridization that involves the dipole modes of the disk and the cavity enforces the "coupling" of the plane-wave excitation to the originally-dark higher-order modes. It is further demonstrated that the resonance frequencies can be tuned by varying the radius of the embedded non-concentric cavity. The near-field enhancement observed at these two tunable resonance frequencies suggests that the proposed structure can be used as a substrate in surface enhanced spectroscopy applications. © 2011 IEEE.
Extending resonant inelastic X-ray scattering to the extreme ultraviolet
Directory of Open Access Journals (Sweden)
L. Andrew eWray
2015-05-01
Full Text Available In resonant inelastic X-ray scattering (RIXS, core hole resonance modes are used to enhance coupling between photons and low energy electronic degrees of freedom. Resonating with shallow core holes accessed in the extreme ultraviolet (EUV can provide greatly improved energy resolution at standard resolving power, but has been found to often yield qualitatively different spectra than similar measurements performed with higher energy X-rays. This paper uses experimental data and multiplet-based numerical simulations for the M-edges of Co-, Ni- and Cu-based Mott insulators to review the properties that distinguish EUV RIXS from more commonly performed higher energy measurements. Key factors such as the origin of the strong EUV elastic line and advantages of EUV spectral functions over soft X-ray RIXS for identifying intrinsic excitation line shapes are discussed.
Liu, Z Z; Xiao, J J
2015-01-01
We study the optical properties associated to both the polariton gap and the Bragg gap in periodic resonator-waveguide coupled system, based on the temporal coupled mode theory and the transfer matrix method. By the complex band and the transmission spectrum, it is feasible to tune the interaction between multiple Bragg scattering and the local resonance, which may give rise to analogous phenomena of electromagnetically induced transparency (EIT). We further design a plasmonic slot waveguide side-coupled with local plasmonic resonator to demonstrate the EIT-like effects in the near-infared band. Numerical calculations show that realistic amount of metal Joule loss may destroy the interference and the total absorption is enhanced in the transparency windwo due to the near zero group velocity of the guiding wave.
International Nuclear Information System (INIS)
High-resolution neutron transmission and differential elastic scattering measurements have been made on samples of nitrogen from 0.5 eV to 10 MeV at the Oak Ridge Electron Linear Accelerator (ORELA). For the transmission measurement several different detectors were used at various flight path lengths, with high-purity nitrogen gas samples. The data have been corrected for the dead time of the time digitizer and for several small backgrounds. For the scattering measurements six detectors were placed at various angles inside an evacuated scattering chamber at 200 meters from the neutron producing target. The sample was silicon nitride held in a thin graphite container. Scattering from carbon and silicon samples was also measured to correct for these materials and calibrate the relative efficiencies of the scattering detectors. The data have been corrected for dead time and for a constant background. A preliminary analysis has been completed to obtain parameters of the resonances up to 4.8 MeV
Bakker, E J; Lambert, Eric J. Bakker & David L.
1998-01-01
We have made the first detection of circumstellar absorption lines of the 12C13C (Phillips) system 1-0 band and the 12C16O first-overtone 2-0 band in the spectrum of the post-AGB star HD56126 (IRAS07134+1005). The rotational temperatures are lower for molecules with a higher permanent dipole moment. Derived relative column densities ratios are 12C12C/12C13C=36+-13, 12C16O/(12C12C+12C13C)=606+-230, and 12C16O/(12C14N+13C14N)=475+-175. The isotopic exchange reaction for 12C12C is too slow to significantly alter the 12C12C/12C13C ratio and the 12C12C to 12C13C ratio a good measure of half the carbon isotope ratio: 12C/13C=2 X 12C12C/12C13C=72+-26. A fit of the 12C12C excitation model of van Dishoeck & Black (1982) to the relative population distribution of 12C12C yields n sigma / I = 3.3 +- 1.0 X 1e-14. At r=1e16cm this translates in n=1.7e7cm-3 and dM/dt=2.5e-4Msol/year.
Energy Technology Data Exchange (ETDEWEB)
Takeuchi, Koh; Gal, Maayan [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States); Takahashi, Hideo; Shimada, Ichio [National Institute of Advanced Industrial Science and Technology, Biomedicinal Information Research Center (Japan); Wagner, Gerhard, E-mail: gerhard_wagner@hms.harvard.edu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States)
2011-01-15
Described here is a set of three-dimensional (3D) NMR experiments that rely on CACA-TOCSY magnetization transfer via the weak {sup 3}J(C{sub {alpha}}C{sub {alpha}}) coupling. These pulse sequences, which resemble recently described {sup 13}C detected CACA-TOCSY (Takeuchi et al. 2010) experiments, are recorded in {sup 1}H{sub 2}O, and use {sup 1}H excitation and detection. These experiments require alternate {sup 13}C-{sup 12}C labeling together with perdeuteration, which allows utilizing the small {sup 3}J(C{sub {alpha}}C{sub {alpha}}) scalar coupling that is otherwise masked by the stronger {sup 1}J{sub CC} couplings in uniformly {sup 13}C labeled samples. These new experiments provide a unique assignment ladder-mark that yields bidirectional supra-sequential information and can readily straddle proline residues. Unlike the conventional HNCA experiment, which contains only sequential information to the {sup 13}(C{sub {alpha}}) of the preceding residue, the 3D hnCA-TOCSY-caNH experiment can yield sequential correlations to alpha carbons in positions i-1, i + 1 and i-2. Furthermore, the 3D hNca-TOCSY-caNH and Hnca-TOCSY-caNH experiments, which share the same magnetization pathway but use a different chemical shift encoding, directly couple the {sup 15}N-{sup 1}H spin pair of residue i to adjacent amide protons and nitrogens at positions i-2, i-1, i + 1 and i + 2, respectively. These new experimental features make protein backbone assignments more robust by reducing the degeneracy problem associated with the conventional 3D NMR experiments.
K-edge resonant x-ray magnetic scattering from a transition-metal oxide: NiO
DEFF Research Database (Denmark)
Hill, J.P.; Kao, C.C.; McMorrow, D.F.
1997-01-01
We report the observation of resonant x-ray magnetic scattering in the vicinity of the Ni K edge in the antiferromagnet NiO. An approximately twofold increase in the scattering is observed as the incident photon energy is tuned through a pre-edge feature in the absorption spectrum, associated wit...
Ainslie, M.A.; Leighton, T.G.
2011-01-01
Perhaps the most familiar concepts when discussing acoustic scattering by bubbles are the resonance frequency for bubble pulsation, the bubbles' damping, and their scattering and extinction cross-sections, all of which are used routinely in oceanography, sonochemistry, and biomedicine. The apparent
Spatial measure of reaction size in proton scattering
Ito, Makoto; Iwasaki, Masataka; Otani, Reiji; Tomita, Masashi
2016-06-01
The microscopic coupled-channel (MCC) calculations for proton + 12C inelastic scattering are performed in the energy range of Ep = 29.95 MeV to 65 MeV. The nuclear interactions for the proton -12C system are constructed from the folding model, which employs the internal wave function of 12C, obtained from the 3α resonating group method (3α RGM), and an effective nucleon-nucleon interaction of the density-dependent Michigan three-range Yukawa (DDM3Y). The MCC calculation with the 3α RGM + DDM3Y nicely reproduces all of the differential cross sections for elastic and inelastic scattering in the angular range of θc.m. = 30° to 120°. We introduce a scattering radius, which characterizes a spatial size of the scattering area, from partial wave decompositions of an angle-integrated cross section. The scattering radii for the elastic scattering and the various inelastic channels, which involve the rotational or vibrational excitations and the 3α excitations in 12C, are derived. We found that the scattering radii for the inelastic channels with a well developed 3α structure are strongly enhanced in comparison to the scattering radii for the elastic and collective channels. This enhancement of the scattering radius for the 3α channel strongly suggests that the scattering radius is sensitive to a size of the intrinsic structure of the finally excited state in the scattering process.
Higher lying resonances in low-energy electron scattering with carbon monoxide
Dora, Amar; Chakrabarti, Kalyan
2016-01-01
R-matrix calculations on electron collisions with CO are reported whose aim is to identify any higher-lying resonances above the well-reported and lowest $^2\\Pi$ resonance at about 1.6~eV. Extensive tests with respect to basis sets, target models and scattering models are performed. The final results are reported for the larger cc-pVTZ basis set using a 50 state close-coupling (CC) calculation. The Breit-Wigner eigenphase sum and the time-delay methods are used to detect and fit any resonances. Both these methods find a very narrow $^2\\Sigma^+$ symmetry Feshbach-type resonance very close to the target excitation threshold of the b $^3\\Sigma^+$ state which lies at 12.9 eV in the calculations. This resonance is seen in the CC calculation using cc-pVTZ basis set while a CC calculation using the cc-pVDZ basis set does not produce this feature. The electronic structure of CO$^-$ is analysed in the asymptotic region, 45 molecular states are found to correlate with states dissociating to an anion and an atom. Electr...
Lorenz-Mie theory for 2D scattering and resonance calculations
Gagnon, Denis
2015-01-01
This PhD tutorial is concerned with a description of the two-dimensional generalized Lorenz-Mie theory (2D-GLMT), a well-established numerical method used to compute the interaction of light with arrays of cylindrical scatterers. This theory is based on the method of separation of variables and the application of an addition theorem for cylindrical functions. The purpose of this tutorial is to assemble the practical tools necessary to implement the 2D-GLMT method for the computation of scattering by passive scatterers or of resonances in optically active media. The first part contains a derivation of the vector and scalar Helmholtz equations for 2D geometries, starting from Maxwell's equations. Optically active media are included in 2D-GLMT using a recent stationary formulation of the Maxwell-Bloch equations called steady-state ab initio laser theory (SALT), which introduces new classes of solutions useful for resonance computations. Following these preliminaries, a detailed description of 2D-GLMT is presente...
Bound and scattering properties in waveguides around free-space Feshbach resonance
Wang, Gaoren; Giannakeas, Panogiotis; Schmelcher, Peter
2016-05-01
The two-body bound and scattering properties in an one-dimensional (1D) harmonic waveguide in the vicinity of free-space magnetic Feshbach resonances are investigated based on the local frame transformation approach. The multichannel characteristics of the interatomic interaction is taken into account. We examine the crossing between the bound state in the waveguide and the ground level of the transverse confinement, i.e. when the bound state crosses the scattering threshold in the waveguide and turns into a continuum state. For s-wave collision, the crossing occurs at the magnetic field where the effective 1D interaction strength g1 D vanishes, and the effective 1D scattering length a1 D diverges. This observation indicates that the molecular formation or atom loss signal in a harmonic waveguide is expected at the magnetic field where a1 D is infinite. Molecule formation is absent at position of the confinement induced resonance which is characterized by the divergence of g1 D . Financial support from Alexander von Humboldt Foundation is acknowledged.
Farnesi, Daniele; Berneschi, Simone; Cosi, Franco; Righini, Giancarlo C; Soria, Silvia; Nunzi Conti, Gualtiero
2016-01-01
Dielectric microspheres can confine light and sound for a length of time through high quality factor whispering gallery modes (WGM). Glass microspheres can be thought as a store of energy with a huge variety of applications: compact laser sources, highly sensitive biochemical sensors and nonlinear phenomena. A protocol for the fabrication of both the microspheres and coupling system is given. The couplers described here are tapered fibers. Efficient generation of nonlinear phenomena related to third order optical non-linear susceptibility Χ((3)) interactions in triply resonant silica microspheres is presented in this paper. The interactions here reported are: Stimulated Raman Scattering (SRS), and four wave mixing processes comprising Stimulated Anti-stokes Raman Scattering (SARS). A proof of the cavity-enhanced phenomenon is given by the lack of correlation among the pump, signal and idler: a resonant mode has to exist in order to obtain the pair of signal and idler. In the case of hyperparametric oscillations (four wave mixing and stimulated anti-stokes Raman scattering), the modes must fulfill the energy and momentum conservation and, last but not least, have a good spatial overlap. PMID:27078752
Energy Technology Data Exchange (ETDEWEB)
Martinez Q, E.; Aguilera, E.F.; Rosales, P. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)
2002-07-01
A fusion process analysis of the {sup 12} C + {sup 12} C reaction is done, using the LILITA program. The analysis consisted mainly in varying the value of the Levels density parameter, determining on this way the value of such parameter which reproduces better the contribution of the different channels of fusion-evaporation of particles for this system at different energies. Moreover a comparison with measures done in the Instituto Nacional de Investigaciones Nucleares is realized. (Author)
Jusserand, B.; Fainstein, A.; Ferreira, R.; Majrab, S.; Lemaitre, A.
2011-01-01
We report on confined exciton resonances of acoustic and folded acoustic phonon light scattering in a GaAs/AlAs multi-quantum-well. Significant variations of the line shifts and widths are observed across the resonance and quantitatively reproduced in terms of the polariton dispersion. This high resolution Brillouin study brings new unexpectedly detailed informations on the polariton dynamics in confined systems.
Theoretical Studies of Direct and Resonant Reactive Scattering Involving Three-Body Systems.
Lutrus, Chen Kwee
The validity of DWBA method is checked to study the direct process for atom-diatomic molecule collisions. The DWBA results for the relative product rotational state distribution for H + D_2 to HD + D are demonstrated to be in good agreement with experimental observations and quasi-classical calculations. Direct comparison between the DWBA and exact close-coupling calculations for the reactive scattering angular distributions of H + H_2 to H_2 + H shows that the structures of angular distribution between the two methods are similar, and the effect of coupling strongly affects the absolute magnitude of cross sections but not the structure of normalized angular distributions. Information theoretic analysis of rotational surprisal is presented for the reactive collision process of H + D_2 to HD + D. Propensity of near linear surprisal at low collision energies and of deviation from linearity at higher collision energies is found. The theoretical formalism of resonance involving three-body systems is presented. Mathematically the three-body quasi-bound state is represented as a linear combination two-body quasi-bound states in terms of each arrangement. Its reduction to the effective two-body representation of the transition amplitude leads to Feshbach's theory of resonance, thus validating our three-body resonant scattering theory. A rigorous derivation of the T matrix is presented to study the effects of direct and resonant reactive scattering processes of e + AB to A + B^-. Analysis of dissociative attachment processes e + H_2 to H + H^- and e + HCl to H + Cl^- is presented, with emphasis on the roles of the direct and resonant processes in the total cross sections. Furthermore, Argand diagram analysis of the transition amplitude for the two dissociative attachment processes is performed. It is found that strong resonance is present in e + HClto H + Cl^-, but not in e + H_2 to H + H^ -. A new recursion relation for the evaluation of overlap between the Morse
DEFF Research Database (Denmark)
Abdali, Salim; Johannessen, Christian; Nygaard, Jesper;
2007-01-01
Using Surface enhanced ROA (SEROA), novel results are achieved by combining Raman Optical Activity (ROA) and resonance Surface Enhanced Raman Scattering (SERRS), applied on myoglobin. The novelty of this work is ascribed the first time reporting on chiral results of a study performed on a protein...... has shown that the SERS effect behaves consequently, depending on the concentration ratio of each component, i.e., myoglobin, Ag colloids and NaCl. Accordingly, it is shown here that SERS intensity has its maximum at certain concentration of these components, whereas below or above this value......, the intensity decreases. The optimization results can be considered as a completion of the hitherto known phenomenon "dilution effect", which takes only account for higher concentrations. Furthermore, the optimization of the parameters seems to be necessary for a successful SEROA measurement, which enables...
Studies of reaction mechanism in {sup 12}C + {sup 12}C system at intermediate energy of 28.7 MeV/N
Energy Technology Data Exchange (ETDEWEB)
Magiera, A. [Inst. of Physics, Jagiellonian Univ., Cracow (Poland)
1996-12-31
The reaction mechanism in {sup 12}C + {sup 12}C system at intermediate energy of about 30 MeV/nucleon was studied. The contribution of various reaction mechanisms (inelastic scattering, transfer reactions, compound nucleus reactions, sequential decay following inelastic excitation and transfer) to the total reaction cross section were found. The analysis of inclusive and coincidence spectra shows that sequential fragmentation processes dominate. 100 refs, 45 figs, 1 tab
Institute of Scientific and Technical Information of China (English)
WU Zhen-Dong; XU Xin-Xing; BAI Chun-Lin; YU Ning; JIA Fei; LIN Cheng-Jian; ZHANG Huan-Qiao; LIU Zu-Hua; YANG Feng; AN Guang-Peng; ZHANG Chun-Lei; ZHANG Gao-Long; JIA Hui-Ming
2009-01-01
The optical potential parameters for the halo nucleus system 6He+12 C are extracted from fits to the measured angular distributions of 11B(7 Li, 6He)12C reaction at energies of 18.3 and 28.3 MeV with distorted-wave Born approximation analysis. The characters of the obtained optical potential parameters are basically consistent with the results extracted from the fits to the elastic-scattering angular distributions in the literature.
Quasi-particle interference of heavy fermions in resonant x-ray scattering
Gyenis, András; da Silva Neto, Eduardo H.; Sutarto, Ronny; Schierle, Enrico; He, Feizhou; Weschke, Eugen; Kavai, Mariam; Baumbach, Ryan E.; Thompson, Joe D.; Bauer, Eric D.; Fisk, Zachary; Damascelli, Andrea; Yazdani, Ali; Aynajian, Pegor
2016-01-01
Resonant x-ray scattering (RXS) has recently become an increasingly important tool for the study of ordering phenomena in correlated electron systems. Yet, the interpretation of RXS experiments remains theoretically challenging because of the complexity of the RXS cross section. Central to this debate is the recent proposal that impurity-induced Friedel oscillations, akin to quasi-particle interference signals observed with a scanning tunneling microscope (STM), can lead to scattering peaks in RXS experiments. The possibility that quasi-particle properties can be probed in RXS measurements opens up a new avenue to study the bulk band structure of materials with the orbital and element selectivity provided by RXS. We test these ideas by combining RXS and STM measurements of the heavy fermion compound CeMIn5 (M = Co, Rh). Temperature- and doping-dependent RXS measurements at the Ce-M4 edge show a broad scattering enhancement that correlates with the appearance of heavy f-electron bands in these compounds. The scattering enhancement is consistent with the measured quasi-particle interference signal in the STM measurements, indicating that the quasi-particle interference can be probed through the momentum distribution of RXS signals. Overall, our experiments demonstrate new opportunities for studies of correlated electronic systems using the RXS technique.
Light scattering resonances in arbitrarily shaped one-dimensional reentrant surfaces
Negrete-Regagnon, Pedro; Hernandez-Walls, Rafael; Ruiz-Cortes, Victor
2000-09-01
Multiple scattering and shape-related effects are an active and important field of research in the area of diffraction and scattering of electromagnetic waves by rough surfaces. Most of the rigorous numerical techniques for dealing with this problem were limited to the treatment of single-valued surfaces. We have extended the formulation of Mendoza- Suarez and Mendez (1997) for dealing with multi-valued profile functions in order to study the scattering of reentrant surfaces or cavities in both, the near and far-field. We have evaluated the near-field in circular cavities with narrow entrances, as well as in the case of clusters of rods or cylinders. Resonant frequencies are clearly identified for these structures. We have also found that our model could be useful to predict wave-induced oscillations in harbors of arbitrary geometry. This comes form the fact that the mathematical formulation of the problem of light scattering by cavities (in the case of p polarization) is similar to the one employed in the case of harbors of arbitrary shape, when a water wave arrives at its entrance (Hwang and Tuck, 1970; Lee, 1971). The results obtained with our model are in close agreement with previously reported theories and experimental data.
Dubrovich, V K
2016-01-01
Within the framework of a flat cosmological model a propagation of an instantaneous burst of isotropic radiation is considered from the moment of its beginning at some initial redshift z0 to the moment of its registration now (at z=0). We take into account Thomson scattering by free electrons and scattering in La and Lb lines of primordial hydrogen and in lines 1s2 - 1s2p, 1s3p (1S-1P*) of HeI. It is shown that relative amplitude of spectrum distortions caused by scattering in these lines may be from 1000 to 10000 times greater than maximum possible amplitude due to scattering in subordinate lines considered in our previous paper (Dubrovich, Grachev, 2015). In a linear approximation on the optical thickness in the lines the profiles of distortions in resonance lines turn out to be purely in absorption and do not depend on both direction and distance to the burst center in contradistinction to the profiles in subordinate lines. The profiles contain jumps on frequencies corresponding to appearance of a source (...
Binding equilibrium of I- to serum albumin with resonance Rayleigh scattering
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The binding equilibrium between I- and human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by means of the resonance Rayleigh scattering (RRS) and equilibrium dialysis. It has been found for the first time that RRS and multiple frequency scattering (MFS) are enhanced as the I- binding to the HSA and BSA, but fluorescence quenches. The equilibrium dialysis results suggest that the binding of I- to HSA and BSA fits a phase-distribution model other than Scatchard model, and that the order of magnitude of its phase-distribution constant was found to be 104. It is most probable that Cl- or other anion ions influence the binding of I- by changing the ionic strength in the solution. The dialysis at different pH indicates that the binding mechanism is due to the electrostatic forces between the I- and protonated basic amino-acid residues.
The Photochemical Study of HSA and BSA with Resonance Light-Scattering and Fluorescence Spectra
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The resonance light-scattering (RLS) of human serum albumin (HSA) and bovine serum albumin (BSA) is reported for the first time, and applied to study photochemical reaction of HSA and BSA. The fact of photocrosslinking self-association effect in HSA and BSA solutions is identified by the enhancement of RLS. The fluorescence quenching at about 350 nm and 700 nm proves that tryptophan (Trp) residues are one of the photochemical activity sites in HSA and BSA molecules. The Rayleigh scattering (RS) spectra of HSA and BSA that were neglected in fluorescence spectra before are found at about 296 nm, 592 nm and 888 nm for the first time, and are of adventageous to studying the aggregation of HSA or BSA. The possible photochemical reaction mechanism is also proposed.
Pion scattering and electro-production on nucleons in the resonance region in chiral quark models
Sirca, Simon; Fiolhais, Manuel; Alberto, Pedro
2011-01-01
Pion scattering and electro-production amplitudes have been computed in a coupled-channel framework incorporating quasi-bound quark-model states, based on the Cloudy Bag model. All relevant low-lying nucleon resonances in the P33, P11, and S11 partial waves have been covered, including the Delta(1232), the N*(1440), N*(1535), and N*(1650). Consistent results have been obtained for elastic and inelastic scattering (two-pion, eta-N, and K-Lambda channels), as well as for electro-production. The meson cloud has been shown to play a major role, in particular in electro-magnetic observables in the P33 and P11 channels.
Institute of Scientific and Technical Information of China (English)
Lian Hui Chen; Yi Jian; Hong Qun Luo; Shao Pu Liu; Xiao Li Hu
2007-01-01
In an acetic acid-sodium acetate buffer solution of pH 3.6-6.8, a compound complex was formed between sodium hyaluronate (abbreviated as SH) and some basic bisphenylnaphthylmethane dyes, leading to a great enhancement of the intensity of resonance Rayleigh scattering (RRS) and giving a new RRS spectrum, with its maximum scattering peak near 280 nm. It was also found that the intensity of RRS was directly proportional to the concentration of SH near the range between 0 and 3.0 mg/L. Based on these facts, a sensitive method for the determination of SH has been established. The method had good selectivity, and has been used for the determination of total amounts of SH in samples with satisfactory results. For the NB-SH system, the detection limit of SH was down to 13.7 ng/mL.
Design of narrow-band Compton scattering sources for nuclear resonance fluorescence
Albert, F.; Anderson, S. G.; Gibson, D. J.; Marsh, R. A.; Wu, S. S.; Siders, C. W.; Barty, C. P. J.; Hartemann, F. V.
2011-05-01
The design of narrow-band Compton scattering sources for specific applications using nuclear resonance fluorescence (NRF) is presented. NRF lines are extremely narrow (ΔE/Ẽ10-6) and require spectrally narrow sources to be excited selectively and efficiently. This paper focuses on the theory of spectral broadening mechanisms involved during Compton scattering of laser photons from relativistic electron beams. It is shown that in addition to the electron beam emittance, energy spread, and the laser parameters, nonlinear processes during the laser-electron interaction can have a detrimental effect on the gamma-ray source bandwidth, including a newly identified weakly nonlinear phase shift accumulated over the effective interaction duration. Finally, a design taking these mechanisms into consideration is outlined.
Binding equilibrium of I~- to serum albumin with resonance Rayleigh scattering
Institute of Scientific and Technical Information of China (English)
梁宏; 沈星灿; 蒋治良; 何锡文; 申泮文
2000-01-01
The binding equilibrium between l- and human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by means of the resonance Rayleigh scattering (RRS) and equilibrium dialysis. It has been found for the first time that RRS and multiple frequency scattering (MFS) are enhanced as the l- binding to the HSA and BSA, but fluorescence quenches. The equilibrium dialysis results suggest that the binding of l- to HSA and BSA fits a phase-distribution model other than Scsitchard model, and that the order of magnitude of its phase-distribution constant was found to be 104. It is most probable that Cl~ or other anion ions influence the binding of P by changing the ionic strength in the solution. The dialysis at different pH indicates that the binding mechanism is due to the electrostatic forces between the T-and protonated basic amino-acid residues.
Extrinsic Spin Hall Effect Induced by Resonant Skew Scattering in Graphene
Ferreira, Aires; Rappoport, Tatiana G.; Cazalilla, Miguel A.; Castro Neto, A. H.
2015-03-01
We show that the extrinsic spin Hall effect can be engineered in monolayer graphene by decoration with small doses of adatoms, molecules, or nanoparticles originating local spin-orbit perturbations. The analysis of the single impurity scattering problem shows that intrinsic and Rashba spin-orbit local couplings enhance the spin Hall effect via skew scattering of charge carriers in the resonant regime. The solution of the transport equations for a random ensemble of spin-orbit impurities reveals that giant spin Hall currents are within the reach of the current state of the art in device fabrication. The spin Hall effect is robust with respect to thermal fluctuations and disorder averaging. The author acknowledges support from the National Research Foundation-Competitive Research Programme through Grant No. R-144-000-295-281.
Local versus nonlocal $\\alpha\\alpha$ interactions in $3\\alpha$ description of $^{12}$C
Suzuki, Y; Descouvemont, P; Fujiwara, Y; Matsumura, H; Orabi, M; Theeten, M
2008-01-01
Local $\\alpha \\alpha$ potentials fail to describe $^{12}$C as a $3\\alpha$ system. Nonlocal $\\alpha \\alpha$ potentials that renormalize the energy-dependent kernel of the resonating group method allow interpreting simultaneously the ground state and $0^+_2$ resonance of $^{12}$C as $3\\alpha$ states. A comparison with fully microscopic calculations provides a measure of the importance of three-cluster exchanges in those states.
The 12C* Hoyle state in the inelastic 12C + 12C reaction and in 24Mg* decay
Morelli, L.; Bruno, M.; D'Agostino, M.; Baiocco, G.; Gulminelli, F.; Abbondanno, U.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gramegna, F.; Mabiala, J.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.
2016-08-01
The reaction 12C + 12C at 95 MeV has been studied at the Legnaro Laboratories of INFN with the GARFIELD + RCo apparatus. Data have been analyzed in order to investigate the decay of the Hoyle state of 12C*. Two different data selections have been made. The first one corresponds to peripheral binary collisions where the quasi-projectile is excited to the Hoyle state and the target has been left in the ground state. The second selection allows for studying central events with the formation of a 24Mg* and the Hoyle state is obtained as a step of the decay chain. The characteristics of the Hoyle state decay are very similar in the two samples and point to a mainly sequential decay through the population of an intermediate 8Begs, with a small contribution (˜1.1%) from simultaneous three α-particle processes.
Band dispersion of MgB sub 2 , graphite and diamond from resonant inelastic scattering
Sokolov, A V; Leitch, S; Moewes, A; Kortus, J; Finkelstein, L D; Skorikov, N A; Xiao, C; Hirose, A
2003-01-01
The quantitative band mapping for MgB sub 2 , graphite and diamond are realized using resonant inelastic x-ray scattering (RIXS) measurements. RIXS shows distinct dispersive features when the excitation energy is tuned near B 1s and C 1s thresholds, which are assigned to the calculated energy bands using k sup->-momentum conservation. The agreement between experiment and theory suggests that electron-electron interactions are not important for MgB sub 2 , which behaves like a conventional metal and is well described by band theory.
Theoretical and experimental study of resonant inelastic X-ray scattering for NiO
International Nuclear Information System (INIS)
Resonant inelastic X-ray scattering (RIXS) spectra for Ni 2p to 3d excitation and 3d to 2p de-excitation of NiO are studied both theoretically and experimentally. Theoretical calculations with a single impurity Anderson model (SIAM) describe the charge transfer (CT) and d-d excitations in RIXS, and detailed study is made for the CT energy. High resolution RIXS measurements reveal the precise d-d excitation structure and its polarization dependence, and they are well reproduced by the SIAM calculation
Theoretical and experimental study of resonant inelastic X-ray scattering for NiO
Energy Technology Data Exchange (ETDEWEB)
Kotani, A. [RIKEN Harima Institute, 1-1-1 Kouto, Mikazuki-cho, Sayo-gun, Hyogo, 679-5148 (Japan) and Photon Factory, Institute of Materials Structure Science, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)]. E-mail: kotani@spring8.or.jp; Matsubara, M. [Laboratory of Physics, Helsinki University of Technology, P.O. Box 1100, FIN-02015 HUT (Finland); Uozumi, T. [College of Engineering, Osaka Prefecture University, Sakai, Osaka 599-8531 (Japan); Ghiringhelli, G. [INFM-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Fracassi, F. [INFM-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Dallera, C. [INFM-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Tagliaferri, A. [INFM-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy); Brookes, N.B. [European Synchrotron Radiation Facility, B.P. 220, 38043 Grenoble Cedex (France); Braicovich, L. [INFM-Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan (Italy)
2006-11-15
Resonant inelastic X-ray scattering (RIXS) spectra for Ni 2p to 3d excitation and 3d to 2p de-excitation of NiO are studied both theoretically and experimentally. Theoretical calculations with a single impurity Anderson model (SIAM) describe the charge transfer (CT) and d-d excitations in RIXS, and detailed study is made for the CT energy. High resolution RIXS measurements reveal the precise d-d excitation structure and its polarization dependence, and they are well reproduced by the SIAM calculation.
Energy Technology Data Exchange (ETDEWEB)
Jungmann, C.R.; Weigmann, H. (Commission of the European Communities, Geel (Belgium). Central Bureau for Nuclear Measurements); Mewissen, L.; Poortmans, F. (Centre d' Etude de l' Energie Nucleaire, Mol (Belgium)); Cornels, E. (Rijksuniversitair Centrum te Antwerpen (Belgium)); Theobald, J.P. (Technische Hochschule Darmstadt (Germany, F.R.). Inst. fuer Kernphysik)
1982-09-27
Neutron transmission experiments were performed on /sup 32/S between 0.18 MeV and 19 MeV and differential elastic scattering experiments up to 2 MeV. The resonance parameters, including spin and parity, were determined up to 1.7 MeV. The distribution of neutron strength was determined for ssub(1/2), psub(1/2), psub(3/2), dsub(3/2), dsub(5/2) and f-wave levels, and is compared to recent model calculations. The isotopic purity of some possible T = 3/2 isobaric analog states was deduced from their neutron widths.
X-ray suppression in gamma-ray bursts through resonant Compton scattering
Brainerd, J. J.
1992-01-01
An X-ray that scatters with an electron in the first Landau level of a strong magnetic field is converted into a gamma ray. This process has a resonant cross section at X-ray energies and is therefore highly likely to occur even when the first Landau level is sparsely populated. Converted X-rays are cyclotron absorbed, maintaining the equilibrium between the cyclotron photon density and the population of the first Landau level. By suppressing a neutron star's black body emission, this mechanism can produce a gamma-ray burst with a low X-ray flux.
Tallur, Siddharth
2013-01-01
Finite photon lifetimes for light fields in an opto-mechanical cavity impose a bandwidth limit on displacement sensing at mechanical resonance frequencies beyond the loaded cavity photon decay rate. Opto-mechanical modulation efficiency can be enhanced via multi-GHz transduction techniques such as piezo-opto-mechanics at the cost of on-chip integration. In this paper, we present a novel high bandwidth displacement sense scheme employing Rayleigh scattering in photonic resonators. Using this technique in conjunction with on-chip electrostatic drive in silicon enables efficient modulation at frequencies up to 9.1GHz. Being independent of the drive mechanism, this scheme could readily be extended to piezo-opto-mechanical and all optical transduced systems.
Proton resonance elastic scattering of $^{30}$Mg for single particle structure of $^{31}$Mg
The single particle structure of $^{31}$Mg, which is located in the so-called “island of inversion”, will be studied through measuring Isobaric Analog Resonances (IARs) of bound states of $^{31}$Mg. They are located in the high excitation energy of $^{31}$Al. We are going to determine the spectroscopic factors and angular momenta of the parent states by measuring the excitation function of the proton resonance elastic scattering around 0 degrees in the laboratory frame with around 3 MeV/nucleon $^{30}$Mg beam. The present study will reveal the shell evolution around $^{32}$Mg. In addition, the spectroscopic factor of the (7/2)$^{−}$ state which was not yet determined experimentally, may allow one to study the shape coexistence in this nucleus.
Cooperative resonances in light scattering from two-dimensional atomic arrays
Shahmoon, Ephraim; Lukin, Mikhail D; Yelin, Susanne F
2016-01-01
We consider light scattering off a two-dimensional (2D) dipolar array and show how it can be tailored by properly choosing the lattice constant of the order of the incident wavelength. In particular, we demonstrate that such arrays can operate as nearly perfect mirrors for a wide range of incident angles and frequencies close to the individual atomic resonance. These results can be understood in terms of the cooperative resonances of the surface modes supported by the 2D array. Experimental realizations are discussed, using ultracold arrays of trapped atoms and excitons in 2D semiconductor materials, as well as potential applications ranging from atomically thin metasurfaces to single photon nonlinear optics and nanomechanics.
Jurna, Martin; Garbacik, Erik T; Korterik, Jeroen P; Herek, Jennifer L; Otto, Cees; Offerhaus, Herman L
2010-09-15
In coherent anti-Stokes Raman scattering (CARS), the emitted signal carries both amplitude and phase information of the molecules in the focal volume. Most CARS experiments ignore the phase component, but its detection allows for two advantages over intensity-only CARS. First, the pure resonant response can be determined, and the nonresonant background rejected, by extracting the imaginary component of the complex response, enhancing the sensitivity of CARS measurements. Second, selectivity is increased via determination of the phase and amplitude, allowing separation of individual molecular components of a sample even when their vibrational bands overlap. Here, using vibrational phase contrast CARS (VPC-CARS), we demonstrate enhanced sensitivity in quantitative measurements of ethanol/methanol mixtures and increased selectivity in a heterogeneous mixture of plastics and water. This powerful technique opens a wide range of possibilities for studies of complicated systems where overlapping resonances limit standard methodologies. PMID:20731373
Resonant scattering of light in a near-black-hole metric
Stadnik, Y V; Flambaum, V V; Berengut, J C
2012-01-01
We show that low-energy photon scattering from a body with radius $R$ slightly larger than its Schwarzschild radius $r_s$ resembles black-hole absorption. This absorption occurs via capture to one of the many long-lived, densely packed resonances that populate the continuum. The lifetimes and density of these meta-stable states tend to infinity in the limit $r_s \\to R$. We determine the energy averaged cross-section for particle capture into these resonances and show that it is equal to the absorption cross-section for a Schwarzschild black hole. Thus, a non-singular static metric may trap photons for arbitrarily long times, making it appear completely `black' before the actual formation of a black hole.
Duan, Sai; Luo, Yi
2015-01-01
The Raman intensity can be well described by the famous Albrecht equation that consists of $A$ and $B$ terms. It has become a textbook knowledge that the contribution from Albrecht's $A$ term can be neglected without loss of accuracy for non-resonant Raman scattering processes. However, as demonstrated in this study, we have found that this widely accepted long-standing assumption fails drastically for totally symmetric vibration modes of molecules. Perturbed first principles calculations for water molecule show that strong constructive interference between the $A$ and $B$ terms occurs for the Raman intensity of the symmetric O-H stretching mode, which can account for about 40% of the total intensity. Meanwhile, a minor destructive interference is found for the angle bending mode. The state to state mapping between the Albrecht's theory and the perturbation theory allows us to verify the accuracy of the widely employed perturbation method for the dynamic/resonant Raman intensities. The model calculations show...
Observation of Λ-hypernuclei in the reaction 12C(π+,K+)/sub Λ/12C
International Nuclear Information System (INIS)
The observation of Λ-hypernuclear levels in /sub Λ/12C by associated production through the (π+,K+) reaction is reported. Spectrometers used in the measurements are discussed. The /sub Λ/12C excitation energy spectra were recorded at laboratory scattering angles of 5.60, 10.30, and 15.20. The spectra show two major peaks - one attributed to the ground state, and one about 11 MeV higher in excitation. The peak near 11 MeV excitation energy is believed to be almost entirely composed of a multiplet of three J/sup π/ = 2+ states. Relativistic DWBA calculations imply support for the expectation that higher spin states are preferentially populated in the (π+,K+) reaction, compared to the (K-,π-) reaction in which lower spin states are excited. 29 refs., 40 figs
Energy Technology Data Exchange (ETDEWEB)
Milner, E.C.
1985-12-01
The observation of ..lambda..-hypernuclear levels in /sub ..lambda..//sup 12/C by associated production through the (..pi../sup +/,K/sup +/) reaction is reported. Spectrometers used in the measurements are discussed. The /sub ..lambda..//sup 12/C excitation energy spectra were recorded at laboratory scattering angles of 5.6/sup 0/, 10.3/sup 0/, and 15.2/sup 0/. The spectra show two major peaks - one attributed to the ground state, and one about 11 MeV higher in excitation. The peak near 11 MeV excitation energy is believed to be almost entirely composed of a multiplet of three J/sup ..pi../ = 2/sup +/ states. Relativistic DWBA calculations imply support for the expectation that higher spin states are preferentially populated in the (..pi../sup +/,K/sup +/) reaction, compared to the (K/sup -/,..pi../sup -/) reaction in which lower spin states are excited. 29 refs., 40 figs.
S-, P- and D-wave resonances in positronium-sodium and positronium-potassium scattering
Adhikari, S K; Adhikari, Sadhan K.; Mandal, Puspajit
2001-01-01
Scattering of positronium (Ps) by sodium and potassium atoms has been investigated employing a three-Ps-state coupled-channel model with Ps(1s,2s,2p) states using a time-reversal-symmetric regularized electron-exchange model potential fitted to reproduce accurate theoretical results for PsNa and PsK binding energies. We find a narrow S-wave singlet resonance at 4.58 eV of width 0.002 eV in the Ps-Na system and at 4.77 eV of width 0.003 eV in the Ps-K system. Singlet P-wave resonances in both systems are found at 5.07 eV of width 0.3 eV. Singlet D-wave structures are found at 5.3 eV in both systems. We also report results for elastic and Ps-excitation cross sections for Ps scattering by Na and K.
Schreck, Simon; Pietzsch, Annette; Kennedy, Brian; Såthe, Conny; Miedema, Piter S.; Techert, Simone; Strocov, Vladimir N.; Schmitt, Thorsten; Hennies, Franz; Rubensson, Jan-Erik; Föhlisch, Alexander
2016-01-01
Thermally driven chemistry as well as materials’ functionality are determined by the potential energy surface of a systems electronic ground state. This makes the potential energy surface a central and powerful concept in physics, chemistry and materials science. However, direct experimental access to the potential energy surface locally around atomic centers and to its long-range structure are lacking. Here we demonstrate how sub-natural linewidth resonant inelastic soft x-ray scattering at vibrational resolution is utilized to determine ground state potential energy surfaces locally and detect long-range changes of the potentials that are driven by local modifications. We show how the general concept is applicable not only to small isolated molecules such as O2 but also to strongly interacting systems such as the hydrogen bond network in liquid water. The weak perturbation to the potential energy surface through hydrogen bonding is observed as a trend towards softening of the ground state potential around the coordinating atom. The instrumental developments in high resolution resonant inelastic soft x-ray scattering are currently accelerating and will enable broad application of the presented approach. With this multidimensional potential energy surfaces that characterize collective phenomena such as (bio)molecular function or high-temperature superconductivity will become accessible in near future.
Simulation and analysis of 13N+p elastic resonance scattering
Institute of Scientific and Technical Information of China (English)
WANG You-Bao; QIN Xing; WANG Bao-Xiang; LIU Wei-Ping; LI Zhi-Hong; BAI Xi-Xiang; LIAN Gang; GUO Bing; ZENG Sheng; SU Jun; LI Yun-Ju; JIANG Chao
2009-01-01
The 13N+p elastic resonance scattering has been studied at the secondary radioactive beam facility of CIAE in inverse kinematics via a thick-target method. The excitation function for the 13N(p,p) scattering was obtained in the energy interval of Ecm ≈0.5--3.2 MeV with a 13N secondary beam of (47.8±1.5) MeV. Carefulanalysis of the secondary beam components and extensive Monte-Carlo simulations enable the resolution of the experimental proton spectra. The resonance parameters for five low-lying levels in 140 were deduced by R- matrix fitting calculations with MULTI7 and SAMMY-M6-BETA. The present results show general agreement with those from a recent similar work, and thus confirm the observation of a new 0- level at 5.7 MeV in 14O with an improved width of 400(45) keV.
Bystritsky, V M; Glavanakov, I V; Grabmayr, P; Krechetov, Yu F; Saigushkin, O K; Schuvalov, E N; Tabachenko, A N; Krechetov, Yu. F
2002-01-01
The differential cross section for the $^{12}$C$(\\gamma,\\pi^{+}p)$ reaction has been measured in the $\\Delta$(1232) resonance region at high recoil momenta of the residual nuclear system. The data are analyzed under the assumption that the formation of the $\\pi^+p$ pairs may be interpreted as a $\\gamma\\Delta^{++}\\to\\pi^+p$ process which takes place on a $\\Delta^{++}$ preexisting in the target nucleus. Estimates of the $\\Delta^{++}$ momentum distribution $\\rho_{\\Delta^{++}}(\\bar{p})$=0.17 fm$^3$ for a mean momentum $\\bar{p}=300\\pm49$ MeV/c as well as the number of $\\Delta$ isobars per nucleon $N_\\Delta=0.017$ were obtained for $^{12}$C.
Implantation effects on resonant Raman scattering in CdTe and Cd 0.23Hg 0.77Te
Ramsteiner, M.; Lusson, A.; Wagner, J.; Koidl, P.; Bruder, M.
1990-04-01
We have studied In + implanted CdTe and Cd 0.23Hg 0.77Te by resonant Raman scattering. The laser excitation was in resonance with the EO + Δ O band gap in CdTe or the E1 gap in Cd 0.23Hg 0.77Te. Under these conditions dipole forbidden but defect ind scattering by one longitudinal optical (LO) phonon as well as Fröhlich-induced two-LO phonon scattering is observed. In both cases scattering is found to be strongly affected by ion implantation. In + was implanted at an ion energy of 350 keV with doses ranging from 10 11 to 5×10 14 ions/cm 2. The intensity ratio of the one-LO phonon lines is found to be a quantitative measure of the implantation damage in CdTe and Cd 0.23Hg 0.77Te even for doses as low as 10 11 ions/cm 2. It is shown that the observed effects of implantation damage on resonant Raman scattering by LO phonons are due to a broadening and an energy shift of the corresponding resonances in the Raman scattering efficiency.
12C(02+)+α molecular states in a microscopic four α model
International Nuclear Information System (INIS)
The 16O nucleus is investigated within a 12C+α four α multicluster model. The generator coordinate method combined with the microscopic R-matrix method is used to determine bound and resonant states. The 12C nucleus is described by 3 α clusters located at the apexes of isosceles triangles. We optimize the generator coordinates to get a reasonable description of the 02+–01+ energy gap, where the 02+ is the so-called Hoyle state, considered as a 3 α state. Our calculations mainly focus on resonances located near the 12C(02+)+α threshold. We emphasize the difficulty to interpret broad resonant states and we show that bound state approximation methods are not well adapted in the context of our study. An R-matrix analysis suggests the existence of 0+, 2+ and 4+ molecular states which present a significant 12C(02+)+α structure, and which may form a rotational band
Yang, Shin Nan; Tiator, L
2011-01-01
We present the results on P11 resonances obtained with Dubna-Mainz-Taipei (DMT) dynamical model for pion-nucleon scattering and pion electromagnetic production. The extracted values agree well, in general, with PDG values. One pole is found corresponding to the Roper resonance and two more resonances are definitely needed in DMT model. We further find indication for a narrow P11 resonance at around 1700 MeV with a width of around 50 MeV in both pi-N and gamma-pi reactions.
Investigation of resonant Raman scattering in type II GaAs/AlAs superlattices
Choi, H
2001-01-01
GAMMA-related Type I outgoing RR spectra within several theoretical models. Thereby, the mechanisms of the Type II RR scattering, the origins of the RR lineshape and the polarisation dependence, are fully explained, clarifying the spectral features observed in the GaAs zone-centre optic phonon region. The Type II resonance also allows the observation of zone boundary (X-point) phonons from intervalley (IV) scattering. A model of the IV electron-phonon interaction involving X conduction band electrons and zone boundary phonons in Type II SLs is presented. With the predicted SL selection rules for IV scattering, the simultaneous observation of both the zone-boundary longitudinal acoustic and optic phonons can be understood and the spectral features quantitatively explained. As a consequence of the band alignment in GaAs/AIAs superlattices (SLs) and the indirect nature of bulk AIAs, quantum confinement can be used to engineer a Type II system. This produces an electron population in the AIAs longitudinal (X sub ...
Fiber optic particle plasmon resonance sensor based on plasmonic light scattering interrogation
Energy Technology Data Exchange (ETDEWEB)
Lin, H.Y.; Huang, C.H. [Center for Nano Bio-Detection, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621 (China); Chau, L.K. [Center for Nano Bio-Detection, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621 (China); Department of Chemistry and Biochemistry, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621 (China); Advanced Institute of Manufacturing with High-tech Innovations, National Chung Cheng University, 168 University Road, Minhsiung, Chiayi 621 (China)
2012-11-15
A highly sensitive fiber optic particle plasmon resonance sensor (FO-PPR) is demonstrated for label-free biochemical detection. The sensing strategy relies on interrogating the plasmonic scattering of light from gold nanoparticles on the optical fiber in response to the surrounding refractive index changes or molecular binding events. The refractive index resolution is estimated to be 3.8 x 10{sup -5} RIU. The limit of detection for anti-DNP antibody spiked in buffer is 1.2 x 10{sup -9} g/ml (5.3 pM) by using the DNP-functionalized FO-PPR sensor. The image processing of simultaneously recorded plasmonic scattering photographs at different compartments of the sensor is also demonstrated. Results suggest that the compact sensor can perform multiple independent measurements simultaneously by means of monitoring the plasmonic scattering intensity via photodiodes or a CCD. The potential of using a combination of different kinds of noble metal nanoparticles with different types of functionalized probes in multiple cascaded detection windows on a single fiber to become an inexpensive and ultrasensitive linear-array sensing platform for higher-throughput biochemical detection is provided. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Bremsstrahlung from nuclear scattering at low energy near a resonance. Final report
International Nuclear Information System (INIS)
The understanding of almost all low-energy reaction processes depends upon a distorted wave Born approximation (DWBA) analysis. DWBA procedures, in turn, depend crucially upon a correct optical model description of the projectile-target elastic scattering process. An assumption that the potential is local together with measurements of the elastic scattering data at all energies (0 -infinity) would completely determine that potential, including its off-shell or short-range properties. However, one does not have the luxury of knowing the elastic scattering phase shifts for all energies nor are we so naive as to believe that the potential is completely local. Thus, an alternative approach is called for. The present proposal describes a program to contribute to the general understanding of nuclear reactions by determining as many of the off-shell properties of the proton-nucleus interaction as possible through the study of the proton-nucleus bremsstrahlung process. We seek to establish the limits of validity of a model independent analysis of these reactions in the neighborhood of a resonance or a breakup threshold, and to utilize the differences between this analysis and the data to elucidate those off-shell constraints which any valid proton-nucleus model interaction must satisfy. The bremsstrahlung process provides a method for determining the off-shell properties of the proton-nucleus potential, and the Brooklyn College program offers a unique opportunity to measure these crucial aspects of the low energy proton-nucleus interaction. 18 references
Development of Resonant Soft X-ray Scattering for Polymer Systems at Advanced Light Source
Wang, Cheng; Hexemer, Alexander; Nasiatka, James; Chan, Elaine; Padmore, Howard
2010-03-01
It is envisioned that many polymer applications will rely on the heterogeneous morphologies of polymer blends or block copolymers to yield specific functional properties, such as organic light-emitting diodes and photovoltaics. Over the past few years, it has been strongly demonstrated that scattering at soft x-ray energies near the carbon K-edge yields chemically specific and enhanced contrast, thereby enabling structural studies of heterogeneous polymer films with thicknesses of only tens of nanometers. Resonant soft x-ray scattering (RSoXS) will provide the capability for a high-resolution chemical probe with interfacial sensitivity. We will discuss here the development of a dedicated RSoXS setup at the ALS Beamline 11.0.1, which is an elliptically polarized undulator beamline that covers the energy range of 200-1300 eV. It can accommodate a large variety of thin film samples and scattering geometries, including transmission, specular and off-specular reflection, as well as grazing incidence geometries, that will enable users to study both laterally- and depth-resolved structures. The generality, strength, and ease of RSoXS will have significant and immediate impacts in many areas of polymer science and technology. This will be achieved through systematic, collaborative studies of materials with potentially high impact applications.
Fiber optic particle plasmon resonance sensor based on plasmonic light scattering interrogation
International Nuclear Information System (INIS)
A highly sensitive fiber optic particle plasmon resonance sensor (FO-PPR) is demonstrated for label-free biochemical detection. The sensing strategy relies on interrogating the plasmonic scattering of light from gold nanoparticles on the optical fiber in response to the surrounding refractive index changes or molecular binding events. The refractive index resolution is estimated to be 3.8 x 10-5 RIU. The limit of detection for anti-DNP antibody spiked in buffer is 1.2 x 10-9 g/ml (5.3 pM) by using the DNP-functionalized FO-PPR sensor. The image processing of simultaneously recorded plasmonic scattering photographs at different compartments of the sensor is also demonstrated. Results suggest that the compact sensor can perform multiple independent measurements simultaneously by means of monitoring the plasmonic scattering intensity via photodiodes or a CCD. The potential of using a combination of different kinds of noble metal nanoparticles with different types of functionalized probes in multiple cascaded detection windows on a single fiber to become an inexpensive and ultrasensitive linear-array sensing platform for higher-throughput biochemical detection is provided. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Energy Technology Data Exchange (ETDEWEB)
Takemoto, Hiroki; Horiuchi, Hisashi [Kyoto Univ. (Japan). Dept. of Physics; Ono, Akira
1997-05-01
In general, self-conjugate 4n-nuclei have anomalous excited states with the excitation energy 10-15 MeV, which are recognized to be generated by the change of the structure from the shell-model-like one into the cluster one due to the activation of the clustering degrees of freedom. In AMD (Antisymmetrized Molecular Dynamics) fermic nature of nucleons is treated exactly, because the wave function of A-body system is antisymmetrized by a Slater determinant. Hence Pauli principle has been fully incorporated in AMD. As a result, it was concluded that the features of {sup 12}C fragmentation are originated from the activation of alpha-cluster degrees of freedom by indicating the excitation energy spectra of {sup 12}C before its breakup at the dynamical stage. Excitation energy spectrum before {sup 12}C breakup into any fragments consists of two components. One distributes in the range 7-15 MeV and the other in the range above 15 MeV. Accordingly, the features is related to those excited states excited states of {sup 12}C that is considered to have the cluster structure. (G.K.)
Gold split-ring resonators (SRRs) as substrates for surface-enhanced raman scattering
Yue, Weisheng
2013-10-24
We used gold split ring resonators (SRRs) as substrates for surface-enhanced Raman scattering (SERS). The arrays of SRRs were fabricated by electron-beam lithography in combination with plasma etching. In the detection of rhodamine 6G (R6G) molecules, SERS enhancement factors of the order of 105 was achieved. This SERS enhancement increased as the size of the split gap decrease as a consequence of the matching between the resonance wavelength of the SRRs and the excitation wavelength of SERS. As the size of the split gap decreased, the localized surface plasmon resonance shifted to near the excitation wavelength and, thus, resulted in the increase in the electric field on the nanostructures. We used finite integration method (FIT) to simulate numerically the electromagnetic properties of the SRRs. The results of the simulation agreed well with our experimental observations. We anticipate this work will provide an approach to manipulate the SERS enhancement by modulating the size of split gap with SRRs without affecting the area and structural arrangement. © 2013 American Chemical Society.
Transition from resonances to surface waves in pi^+-p elastic scattering
De Micheli, Enrico
2013-01-01
In this article we study resonances and surface waves in $\\pi^+$--p scattering. We focus on the sequence whose spin-parity values are given by $J^p = {3/2}^+,{7/2}^+, {11/2}^+, {15/2}^+,{19/2}^+$. A widely-held belief takes for granted that this sequence can be connected by a moving pole in the complex angular momentum (CAM) plane, which gives rise to a linear trajectory of the form $J = \\alpha_0+\\alpha' m^2$, $\\alpha'\\sim 1/(\\mathrm{GeV})^2$, which is the standard expression of the Regge pole trajectory. But the phenomenology shows that only the first few resonances lie on a trajectory of this type. For higher $J^p$ this rule is violated and is substituted by the relation $J\\sim kR$, where $k$ is the pion--nucleon c.m.s.-momentum, and $R\\sim 1$ fm. In this article we prove: (a) Starting from a non-relativistic model of the proton, regarded as composed by three quarks confined by harmonic potentials, we prove that the first three members of this $\\pi^+$-p resonance sequence can be associated with a vibrationa...
Yao, De-Liang; Siemens, D.; Bernard, V.; Epelbaum, E.; Gasparyan, A. M.; Gegelia, J.; Krebs, H.; Meißner, Ulf-G.
2016-05-01
We present the results of a third order calculation of the pion-nucleon scattering amplitude in a chiral effective field theory with pions, nucleons and delta resonances as explicit degrees of freedom. We work in a manifestly Lorentz invariant formulation of baryon chiral perturbation theory using dimensional regularization and the extended on-mass-shell renormalization scheme. In the delta resonance sector, the on mass-shell renormalization is realized as a complex-mass scheme. By fitting the low-energy constants of the effective Lagrangian to the S- and P -partial waves a satisfactory description of the phase shifts from the analysis of the Roy-Steiner equations is obtained. We predict the phase shifts for the D and F waves and compare them with the results of the analysis of the George Washington University group. The threshold parameters are calculated both in the delta-less and delta-full cases. Based on the determined low-energy constants, we discuss the pion-nucleon sigma term. Additionally, in order to determine the strangeness content of the nucleon, we calculate the octet baryon masses in the presence of decuplet resonances up to next-to-next-to-leading order in SU(3) baryon chiral perturbation theory. The octet baryon sigma terms are predicted as a byproduct of this calculation.
Cao, Xing; Ni, Binbin; Liang, Jun; Xiang, Zheng; Wang, Qi; Shi, Run; Gu, Xudong; Zhou, Chen; Zhao, Zhengyu; Fu, Song; Liu, Jiang
2016-02-01
This is a companion study to Liang et al. (2014) which reported a "reversed" energy-latitude dispersion pattern of ion precipitation in that the lower energy ion precipitation extends to lower latitudes than the higher-energy ion precipitation. Electromagnetic ion cyclotron (EMIC) waves in the central plasma sheet (CPS) have been suggested to account for this reversed-type ion precipitation. To further investigate the association, we perform a comprehensive study of pitch angle diffusion rates induced by EMIC wave and the resultant proton loss timescales at L = 8-12 around the midnight. Comparing the proton scattering rates in the Earth's dipole field and a more realistic quiet time geomagnetic field constructed from the Tsyganenko 2001 (T01) model, we find that use of a realistic, nondipolar magnetic field model not only decreases the minimum resonant energies of CPS protons but also considerably decreases the limit of strong diffusion and changes the proton pitch angle diffusion rates. Adoption of the T01 model increases EMIC wave diffusion rates at > ~ 60° equatorial pitch angles but decreases them at small equatorial pitch angles. Pitch angle scattering coefficients of 1-10 keV protons due to H+ band EMIC waves can exceed the strong diffusion rate for both geomagnetic field models. While He+ and O+ band EMIC waves can only scatter tens of keV protons efficiently to cause a fully filled loss cone at L > 10, in the T01 magnetic field they can also cause efficient scattering of ~ keV protons in the strong diffusion limit at L > 10. The resultant proton loss timescales by EMIC waves with a nominal amplitude of 0.2 nT vary from a few hours to several days, depending on the wave band and L shell. Overall, the results demonstrate that H+ band EMIC waves, once present, can act as a major contributor to the scattering loss of a few keV protons at lower L shells in the CPS, accounting for the reversed energy-latitude dispersion pattern of proton precipitation at low
Inelastic resonant M-scattering of X-rays from Gd metal with inner-shell excitation
International Nuclear Information System (INIS)
The paper presents results on resonant inner-shell scattering in Gd across the M5 threshold; the scattering channel with formally a 4 p hole in the final state is studied. Two scattering channels are in competition: one at constant transferred energy and another at constant outgoing energy. The branching ratio of the process at constant transferred energy is about 5%. It's isolated the many-body satellite structure of the formally 4p3/2 final hole state and it's discussed the importance of the multiplet splitting and of the super Coster-Kronig conversion of this state into another final state with two 4 d holes. The results with resonant M5 excitation are also compared with those of non-resonant excitation well above the M4 threshold. Guidelines for future research are briefly presented
On the \\phi(1020)f_0(980) S-wave scattering and the Y(2175) resonance
Alvarez-Ruso, L; Alarcon, J M
2009-01-01
We have studied the \\phi(1020)f_0(980) S-wave scattering at energies around threshold employing chiral Lagrangians coupled to vector mesons through minimal coupling. The interaction kernel is obtained by considering the f_0(980) as a K\\bar{K} bound state. The Y(2175) resonance is generated in this approach by the self-interactions between the \\phi(1020) and the f_0(980) resonances. We are able to describe the e^+e^-\\to \\phi(1020)f_0(980) recent scattering data to test experimentally our scattering amplitudes, concluding that the Y(2175) resonance has a large \\phi(1020)f_0(980) meson-meson component.
International Nuclear Information System (INIS)
Discovery of Moessbauer effect in a nuclear transition was a remarkable development. It revealed how long-lived nuclear states with relatively low energies in the kiloelectron volt (keV) region can be excited without recoil. This new effect had a unique feature involving a coupling between nuclear physics and solid-state physics, both in terms of physics and sociology. Physics coupling originates from the fact that recoilless emission and absorption or resonance is only possible if the requirement that nuclei have to be bound in a lattice with quantized vibrational states is fulfilled, and that the finite electron density on the nucleus couples to nuclear degrees of freedom leading to hyperfine interactions. thus, Moessbauer spectroscopy allows peering into solid-state effects using unique nuclear transitions. Sociological aspects of this coupling had been equally startling and fruitful. The interaction between diverse scientific communities, who learned to use Moessbauer spectroscopy proved to be very valuable. For example, biologists, geologists, chemists, physics, materials scientists, and archeologists, all sharing a common spectroscopic technique, also learned to appreciate the beauty and intricacies of each other's fields. As a laboratory-based technique, Moessbauer spectroscopy matured by the end of the 1970s. Further exciting developments took place when accelerator-based techniques were employed, like synchrotron radiation or 'in-beam'Moessbauer experiments with implanted radioactive ions. More recently, two Moessbauer spectrometers on the surface of the Mars kept the technique vibrant and viable up until present time. In this chapter, the authors look into some of the unique aspects of nuclear resonance excited with synchrotron radiation as a probe of condensed matter, including magnetism, valence, vibrations, and lattice dynamics, and review the development of nuclear resonance inelastic x-ray scattering (NRIXS) and synchrotron Moessbauer spectroscopy
Wang, D; Subedi, R; Deng, X; Ahmed, Z; Allada, K; Aniol, K A; Armstrong, D S; Arrington, J; Bellini, V; Beminiwattha, R; Benesch, J; Benmokhtar, F; Camsonne, A; Canan, M; Cates, G D; Chen, J -P; Chudakov, E; Cisbani, E; Dalton, M M; de Jager, C W; De Leo, R; Deconinck, W; Deur, A; Dutta, C; Fassi, L El; Flay, D; Franklin, G B; Friend, M; Frullani, S; Garibaldi, F; Giusa, A; Glamazdin, A; Golge, S; Grimm, K; Hafidi, K; Hansen, O; Higinbotham, D W; Holmes, R; Holmstrom, T; Holt, R J; Huang, J; Hyde, C E; Jen, C M; Jones, D; Kang, H; King, P; Kowalski, S; Kumar, K S; Lee, J H; LeRose, J J; Liyanage, N; Long, E; McNulty, D; Margaziotis, D J; Meddi, F; Meekins, D G; Mercado, L; Meziani, Z -E; Michaels, R; Mihovilovic, M; Muangma, N; Myers, K E; Nanda, S; Narayan, A; Nelyubin, V; Nuruzzaman,; Oh, Y; Parno, D; Paschke, K D; Phillips, S K; Qian, X; Qiang, Y; Quinn, B; Rakhman, A; Reimer, P E; Rider, K; Riordan, S; Roche, J; Rubin, J; Russo, G; Saenboonruang, K; Saha, A; Sawatzky, B; Shahinyan, A; Silwal, R; Sirca, S; Souder, P A; Suleiman, R; Sulkosky, V; Sutera, C M; Tobias, W A; Waidyawansa, B; Wojtsekhowski, B; Ye, L; Zhao, B; Zheng, X
2013-01-01
We report on parity-violating asymmetries in the nucleon resonance region measured using $5 - 6$ GeV longitudinally polarized electrons scattering off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the $\\Delta(1232)$, and provide a verification of quark-hadron duality in the nucleon electroweak $\\gamma Z$ interference structure functions at the 10-15% level. The results are of particular interest to models relevant for calculating the $\\gamma Z$ box-diagram corrections to elastic parity-violating electron scattering measurements.
Bachelier, Guillaume; Mlayah, A.; Cazayous, M.; Groenen, J.; Zwick, Antoine; Carrère, Hélène; Bedel, Eléna; Arnoult, Alexandre; Rocher, A.; Ponchet, A.
2003-01-01
Raman measurements on a thick GaAsN layer and on GaAsN/GaAs quantum well structures are reported. The scattering was excited close to resonance with the N-induced E+ transition, and detected in both Stokes and anti-Stokes regions including the low-frequency range around the Rayleigh line. A broad continuous scattering due to acoustic phonons is observed on the thick GaAsN layer. Calculations of the Raman efficiency showed that localization and mixing of the resonant electronic states well acc...
Resonances in rotationally inelastic scattering of NH{sub 3} and ND{sub 3} with H{sub 2}
Energy Technology Data Exchange (ETDEWEB)
Ma, Qianli; Dagdigian, Paul J., E-mail: pjdagdigian@jhu.edu [Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218-2685 (United States); Avoird, Ad van der, E-mail: A.vanderAvoird@theochem.ru.nl; Meerakker, Sebastiaan Y. T. van de [Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Loreau, Jérôme [Service de Chimie Quantique et Photophysique C. P. 160/09, Université Libre de Bruxelles (ULB), 50 Ave. F. D. Roosevelt, 1050 Brussels (Belgium); Alexander, Millard H., E-mail: mha@umd.edu [Department of Chemistry and Biochemistry and Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742-2021 (United States)
2015-07-28
We present theoretical studies on the scattering resonances in rotationally inelastic collisions of NH{sub 3} and ND{sub 3} molecules with H{sub 2} molecules. We use the quantum close-coupling method to compute state-to-state integral and differential cross sections for the NH{sub 3}/ND{sub 3}–H{sub 2} system for collision energies between 5 and 70 cm{sup −1}, using a previously reported potential energy surface [Maret et al., Mon. Not. R. Astron. Soc. 399, 425 (2009)]. We identify the resonances as shape or Feshbach resonances. To analyze these, we use an adiabatic bender model, as well as examination at the scattering wave functions and lifetimes. The strength and width of the resonance peaks suggest that they could be observed in a crossed molecular beam experiment involving a Stark-decelerated NH{sub 3} beam.
Energy Technology Data Exchange (ETDEWEB)
Lutrus, C.K.; Suck Salk, S.H.
1989-01-01
Resonances for rearrangement collisions (reactive scattering) involving the two dissociative attachment processes, e+HCl..-->..H+Cl/sup -/ and e+H/sub 2/..-->..H+H/sup -/, are examined. It is shown from the Argand-diagram representation of transition amplitudes that strong resonance is present in the former but not in the latter. That is, the strong resonance is evidenced by the clear exhibition of a phase change by ..pi.. in a counterclockwise direction in the Argand diagram as the collision energy increases. Such a manifest phase change is absent in the dissociative attachment process of e+H/sub 2/..-->..H+H/sup -/. This is attributed to the presence of equally strong, direct, and resonant scattering processes, and to the strong influence of mutually destructive interference.
Lutrus, C. K.; Suck Salk, S. H.
1989-01-01
Resonances for rearrangement collisions (reactive scattering) involving the two dissociative attachment processes, e+HCl-->H+Cl- and e+H2-->H+H-, are examined. It is shown from the Argand-diagram representation of transition amplitudes that strong resonance is present in the former but not in the latter. That is, the strong resonance is evidenced by the clear exhibition of a phase change by π in a counterclockwise direction in the Argand diagram as the collision energy increases. Such a manifest phase change is absent in the dissociative attachment process of e+H2-->H+H-. This is attributed to the presence of equally strong, direct, and resonant scattering processes, and to the strong influence of mutually destructive interference.
Vieira, H S
2016-01-01
We study the scattering and the resonant frequencies (quasispectrum) of charged massive scalar waves by Kerr-Newman-Kasuya spacetime (dyon black hole). The equations of motion are written into a Heun form, and its analytical solutions are obtained. We obtain the resonant frequencies expression and the general exact regular partial wave solution. The special cases of the Kerr and Schwarzschild black holes are analyzed and the solutions are shown.
The 12C(12C,α)20Ne and 12C(12C,p)23Na reactions at the Gamow peak via the Trojan Horse Method
Tumino, A.; Spitaleri, C.; Cherubini, S.; Guardo, L.; Gulino, M.; Indelicato, I.; La Cognata, M.; Lamia, L.; Pizzone, R. G.; Puglia, S. M. R.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Spartá, R.
2016-05-01
A measurement of the 12C(14N,α20Ne)2H and 12C(14N,p23Na)2Hreactions has been performed at a 14N beam energy of 30.0 MeV. The experiment aims to explore the extent to which contributing 24Mg excited states can be populated in the quasi-free reaction off the deuteron in 14N. In particular, the 24Mg excitation region explored in the measurement plays a key role in stellar carbon burning whose cross section is commonly determined by extrapolating high-energy fusion data. From preliminary results, α and proton channels are clearly identified. In particular, ground and first excited states of 20Ne and 23Na play a major role.
$^{12}$C nuclear reaction measurements for hadrontherapy.
B. Braunn, B; G. Ban, G; J.Colin, J; D. Cussol, D; J.M. Fontbonne, J M; F.R.. Lecolley, F R; C. Pautard, C; Haas, F; Lebhertz, D; Rousseau, M; Stuttge, L; Chevallier, M; Dauvergne, D; Le Foulher, F; Ray, C; Testa, E; Testa, M; Salsac, M D
2010-01-01
Hadrontherapy treatments require a very high precision on the dose deposition ( 2.5% and 1-2mm) in order to keep the benefits of the precise ions’ ballistic. The largest uncertainty on the physical dose deposition is due to ion fragmentation. Up to now, the simulation codes are not able to reproduce the fragmentation process with the required precision. To constraint the nuclear models and complete fragmentation cross sections databases; our collaboration has performed an experiment on May 2008 at GANIL with a 95 MeV/u 12C beam. We have measured the fluence, energy and angular distributions of charged fragments and neutrons coming from nuclear reactions of incident 12C on thick water-like PMMA targets. Preliminary comparisons between GEANT4 (G4BinaryLightIonReaction) simulations and experimental data show huge discrepancies.
The 12C(12C,α20Ne and 12C(12C,p23Na reactions at the Gamow peak via the Trojan Horse Method
Directory of Open Access Journals (Sweden)
Tumino A.
2016-01-01
Full Text Available A measurement of the 12C(14N,α20Ne2H and 12C(14N,p23Na2Hreactions has been performed at a 14N beam energy of 30.0 MeV. The experiment aims to explore the extent to which contributing 24Mg excited states can be populated in the quasi-free reaction off the deuteron in 14N. In particular, the 24Mg excitation region explored in the measurement plays a key role in stellar carbon burning whose cross section is commonly determined by extrapolating high-energy fusion data. From preliminary results, α and proton channels are clearly identified. In particular, ground and first excited states of 20Ne and 23Na play a major role.
Surface-enhanced resonance Raman scattering spectroscopy of single R6G molecules
Institute of Scientific and Technical Information of China (English)
Zhou Zeng-Hui; Liu Li; Wang Gui-Ying; Xu Zhi-Zhan
2006-01-01
Surface-enhanced resonance Raman scattering (SERRS) of Rhodamine 6G (R6G) adsorbed on colloidal silver clusters has been studied. Based on the great enhancement of the Raman signal and the quench of the fluorescence, the SERRS spectra of R6G were recorded for the samples of dye colloidal solution with different concentrations. Spectral inhomogeneity behaviours from single molecules in the dried sample films were observed with complementary evidences, such as spectral polarization, spectral diffusion, intensity fluctuation of vibrational lines and even "breathing" of the molecules. Sequential spectra observed from a liquid sample with an average of 0.3 dye molecules in the probed volume exhibited the expected Poisson distribution for actually measuring 0, 1 or 2 molecules. Difference between the SERRS spectra of R6G excited by linearly and circularly polarized light were experimentally measured.
Resonance light scattering determination of 6-mercaptopurine coupled with HPLC technique
Li, Ai Ping; Peng, Jing Dong; Zhou, MingQiong; Zhang, Jin
2016-02-01
A simple, fast, costless, sensitive and selective method of resonance light scattering coupled with HPLC was established for the determination of 6-mercaptopurine in human urine sample. In a Britton-Robinson buffer solution of pH 5.5, the formation of coordination complex between 6-mercaptopurine and metal palladium (II) led to enhance the RLS intensity of the system. The RLS signal was detected by fluorescence detector at λex = λem = 315 nm. The analytical parameters were provided by the coupled system, the linear of 6-mercaptopurine response from 0.0615 to 2.40 μg L- 1 and the limit of detection (S/N = 3) was 0.05 μg L- 1. The presented method has been applied to determine 6-mercaptopurine in human urine samples which obtained satisfactory results. Moreover, the reaction mechanism and possible reasons for enhancement of RLS were fully discussed.
Resonance Rayleigh Scattering Method for the Determination of Raloxifene with Evans Blue
Institute of Scientific and Technical Information of China (English)
FAN,Li(范莉); LIU,Shao-Pu(刘绍璞); YANG,Da-Cheng(杨大成); HU,Xiao-Li(胡小莉)
2002-01-01
The intensity of resonance Rayleigh scattering ( RRS ) of Evans blue (EB) or raloxifene hydrochloride (Ralo) is very weak,but it can be enhanced significantly and a new RRS spectrum appears when both of them interact to form an ion-assaciafion complex in sodium acetate-hydrochloric acid buffer solution at pH 1.8. The intensity of RRS is directly proportional to the concentration of Ralo in the range of 0-8.3 μg@mL-1, and the detection limit for Ralo (σ=3) is 18.9 ng@mL-1. The method has high sensitivity and fairly good selectivity. Based on the above evidences, a new facile method for the determination of trace amount of Ralo has been established with satisfactory results.
Institute of Scientific and Technical Information of China (English)
2008-01-01
It was found that multi-walled carbon nanotubes (MWNTs) could catalyze the redox reaction between chlorauric acid (HAuCl4) and reductive drugs such as tetracycline hydrochloride (TC), producing gold nanoparticles (Au NPs). By measuring the plasmon resonance light scattering (PRLS) signals of the resulting Au NPs, tetracycline hydrochloride can be detected simply and rapidly with a linear range of 4―26 μmol/L, a correlated coefficient (r ) of 0.9955, and a limit of detection (3σ) of 6.0 nmol/L. This method has been successfully applied to the detection of tetracycline hydrochloride tablets in clinic with the recovery of 101.9% and that of fresh urine samples with the recovery of 98.3%―102.0%.
International Nuclear Information System (INIS)
High-resolution neutron transmission, capture and differential elastic scattering measurements have been made for 58Ni-enriched targets at the Oak Ridge Electron Linear Accelerator (ORELA) from the eV to the MeV region. The three sets of data were analyzed simultaneously from 10 to 450 keV, and the transmission analysis was extended to 650 keV. For the 52 s-wave resonances observed between 10 and 650 keV, the average level spacing, D0, and the strength function, S0, are 12.2 +- 1.0 keV and (3.1 +- 0.6) x 10-4, respectively
Bairamov, B. Kh.
2016-04-01
This paper reports on the formation of complexes consisting of isolated free-standing crystalline semiconductor quantum dots, for example, nc-Si/SiO2, functionalized by short oligonucleotides, for example, the single-stranded system d(20G, 20T). Here, d are deoxyribonucleotides, G and T are guanine and thymine nucleotides, respectively. It has been found that these complexes are unique objects for the elucidation of the specific features in the manifestation of new quantum-size effects in biomacromolecules. It has been demonstrated that the possibility exists of detecting and recording, in such complexes of biomacromolecules, spectrally selective resonance enhancement of Raman scattering intensity in fluctuations of nucleotide molecules due to coherent nonradiative transfer of a photoexcited electron and a hole at the interface of the complex. This dynamic optical imaging of spectral responses can be of applied interest for the development of nanobiophotonic technologies.
The optical/ultraviolet excess of isolated neutron stars in the resonant cyclotron scattering model
Institute of Scientific and Technical Information of China (English)
Hao Tong; Ren-Xin Xu; Li-Ming Song
2011-01-01
X-ray dim isolated neutron stars are peculiar pulsar-like objects,characterized by their Planck-like spectrum.In studying their spectral energy distributions,optical/ultraviolet (UV) excess is a long standing problem.Recently Kaplan et al.measured the optical/UV excess for all seven sources,which is understandable in the resonant cyclotron scattering (RCS) model previously addressed.The RCS model calculations show that the RCS process can account for the observed optical/UV excess for most sources.The flat spectrum of RX J2143.0+0654 may be due to contributions from the bremsstrahlung emission of the electron system in addition to the RCS process.
Institute of Scientific and Technical Information of China (English)
HU Po; HUANG ChengZhi; ZHANG Li
2008-01-01
It was found that multi-walled carbon nanotubes (MWNTs) could catalyze the redox reaction between chlorauric acid (HAuCl4) and reductive drugs such as tetracycline hydrochloride (TC), producing gold nanoparticles (Au NPs). By measuring the plasmon resonance light scattering (PRLS) signals of the resulting Au NPs, tetracycline hydrochloride can be detected simply and rapidly with a linear range of 4-26 μmol/L, a correlated coefficient (r) of 0.9955, and a limit of detection (3σ) of 6.0 nmol/L. This method has been successfully applied to the detection of tetracycline hydrochloride tablets in clinic with the recovery of 101.9% and that of fresh urine samples with the recovery of 96.3%-102.0%.
Institute of Scientific and Technical Information of China (English)
2008-01-01
Silver nanoparticles were prepared under a microwave high-pressure condition using citric acid sodium as a reducer while the excess citrate was removed under high speed centrifugation. There is a resonance scattering (RS) peak at 470 nm for silver nanoparticles. In a pH 4.0 HAc-NaAc buffer solution, hydroxyl radicals from the Fenton reaction can oxidize silver nanoparticles to Ag+, resulting in the RS intensity decreasing. The decreased RS intensity at 470 nm (△I 470 nm) is linear with respect to the concentration of H2O2 (C) in the range of 0.27-7.56 μmol/L with a detection limit of 0.23 μmol/L. Its regression equation is △I 470 nm = 24.3 C + 13.8 with a correlation coefficient of 0.9959. This method was applied to screening the antioxidants with satisfactory results.
Institute of Scientific and Technical Information of China (English)
LIANG AiHui; ZHANG NanNan; JIANG ZhiLiang; LIU RongJin
2008-01-01
Silver nanoparUcles were prepared under a microwave high-pressure condition using citric acid so-dium as a reducer while the excess citrate was removed under high speed centrifugation. There is a resonance scattering (RS) peak at 470 nm for silver nanoparticles. In a pH 4.0 HAc-NaAc buffer solution, hydroxyl radicals from the Fenton reaction can oxidize silver nanoparticles to Ag+, resulting in the RS intensity decreasing. The decreased RS intensity at 470 nm (△/470nm) is linear with respect to the con-centration of H2O2 (C) in the range of 0.27-7.56 μmol/L with a detection limit of 0.23 μmol/L. Its regres-sion equation is △/470nm= 24.3 C + 13.8 with a correlation coefficient of 0.9959. This method was applied to screening the antioxidants with satisfactory results.
Non-Fermi Liquid Behavior Induced by Resonant Diquark-pair Scattering in Heated Quark Matter
Kitazawa, M; Nemoto, Y; Kitazawa, Masakiyo; Kunihiro, Teiji; Nemoto, Yukio
2005-01-01
We show how the quasiparticle picture of quarks changes near but above the critical temperature T_c of the color-superconducting phase transition in the heated quark matter. We demonstrate that a non-Fermi liquid behavior of the matter develops drastically when the diquark coupling constant is increased owing to the coupling of the quark with the pairing soft mode: We clarify that the depression and eventually the appearance of a gap structure in the spectral function as well as the anomalous quark dispersion relation of the quark can be understood in terms of the resonant scattering between the incident quark and a particle near the Fermi surface to make the pairing soft mode.
Isoscalar $\\pi\\pi$ scattering and the $\\sigma$ meson resonance from QCD
Briceno, Raul A; Edwards, Robert G; Wilson, David J
2016-01-01
We present for the first time a determination of the energy dependence of the isoscalar $\\pi\\pi$ elastic scattering phase-shift within a first-principles numerical lattice approach to QCD. Hadronic correlation functions are computed including all required quark propagation diagrams, and from these the discrete spectrum of states in the finite volume defined by the lattice boundary is extracted. From the volume dependence of the spectrum we obtain the $S$-wave phase-shift up to the $K\\overline{K}$ threshold. Calculations are performed at two values of the $u,d$ quark mass corresponding to $m_\\pi = 236, 391$ MeV and the resulting amplitudes are described in terms of a $\\sigma$ meson which evolves from a bound-state below $\\pi\\pi$ threshold at the heavier quark mass, to a broad resonance at the lighter quark mass.
Resonant magnetic X-ray scattering studies of heavy fermion superconductors
Energy Technology Data Exchange (ETDEWEB)
Gaulin, B.D. (Department of Physics and Astronomy, McMaster University, Hamilton, ON (Canada)); Isaacs, E.D. (AT and T Bell Laboratories, Murray Hill, NJ 07973 (United States)); Lussier, J.G. (Department of Physics and Astronomy, McMaster University, Hamilton, ON (Canada)); Reimers, J.N. (Department of Physics and Astronomy, McMaster University, Hamilton, ON (Canada)); Gibbs, D. (Physics Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)); Zschack, P. (Oak Ridge Institute for Science and Education, Brookhaven National Laboratory, Upton, NY 11973 (United States)); Schroeder, A. (Department of Physics and Astronomy, McMaster University, Hamilton, ON (Canada)); Taillefer, L. (Laboratoire Louis-Neel, CNRS, 38042, Grenoble (France)); Garrett, J.D. (Department of Physics and Astronomy, McMaster University, Hamilton, ON (Canada))
1994-04-01
The uranium-based heavy fermion superconductors which are known to display weak antiferromagnetism at low temperatures are well suited to study by the newly developed resonant magnetic X-ray scattering technique. We review recent synchrotron X-ray scattering studies of the magnetic behavior of UPd[sub 2]Al[sub 3] and URu[sub 2]Si[sub 2] and the interaction between magnetism and superconductivity in these materials. These measurements show resolution-limited magnetic Bragg peaks in UPd[sub 2]Al[sub 3] in contrast to those in URu[sub 2]Si[sub 2]. The order parameter as measured at the (0 0 [l brace]1[r brace]/[l brace]2[r brace]) magnetic reciprocal lattice position in UPd[sub 2]Al[sub 3] is different from that at (0, 0, [l brace]3[r brace]/[l brace]2[r brace]), the latter of which indicates a strong anomaly at T[sub N1] similar 11.8 K below the sharp onset of the antiferromagnetic phase at T[sub N] similar 14.5 K. Finally, the behavior of the (0 0 [l brace]1[r brace]/[l brace]2[r brace]) order parameter is smooth for T[<=]T[sub C]=2.00[+-]0.04 K. ((orig.))
Tomographic imaging of flourescence resonance energy transfer in highly light scattering media
Soloviev, Vadim Y.; McGinty, James; Tahir, Khadija B.; Laine, Romain; Stuckey, Daniel W.; Mohan, P. Surya; Hajnal, Joseph V.; Sardini, Alessandro; French, Paul M. W.; Arridge, Simon R.
2010-02-01
Three-dimensional localization of protein conformation changes in turbid media using Förster Resonance Energy Transfer (FRET) was investigated by tomographic fluorescence lifetime imaging (FLIM). FRET occurs when a donor fluorophore, initially in its electronic excited state, transfers energy to an acceptor fluorophore in close proximity through non-radiative dipole-dipole coupling. An acceptor effectively behaves as a quencher of the donor's fluorescence. The quenching process is accompanied by a reduction in the quantum yield and lifetime of the donor fluorophore. Therefore, FRET can be localized by imaging changes in the quantum yield and the fluorescence lifetime of the donor fluorophore. Extending FRET to diffuse optical tomography has potentially important applications such as in vivo studies in small animal. We show that FRET can be localized by reconstructing the quantum yield and lifetime distribution from time-resolved non-invasive boundary measurements of fluorescence and transmitted excitation radiation. Image reconstruction was obtained by an inverse scattering algorithm. Thus we report, to the best of our knowledge, the first tomographic FLIM-FRET imaging in turbid media. The approach is demonstrated by imaging a highly scattering cylindrical phantom concealing two thin wells containing cytosol preparations of HEK293 cells expressing TN-L15, a cytosolic genetically-encoded calcium FRET sensor. A 10mM calcium chloride solution was added to one of the wells to induce a protein conformation change upon binding to TN-L15, resulting in FRET and a corresponding decrease in the donor fluorescence lifetime. The resulting fluorescence lifetime distribution, the quantum efficiency, absorption and scattering coefficients were reconstructed.
Yao, De-Liang; Bernard, V; Epelbaum, E; Gasparyan, A M; Gegelia, J; Krebs, H; Meißner, Ulf-G
2016-01-01
We present the results of a third order calculation of the pion-nucleon scattering amplitude in a chiral effective field theory with pions, nucleons and delta resonances as explicit degrees of freedom. We work in a manifestly Lorentz invariant formulation of baryon chiral perturbation theory using dimensional regularization and the extended on-mass-shell renormalization scheme. In the delta resonance sector, the on mass-shell renormalization is realized as a complex-mass scheme. By fitting the low-energy constants of the effective Lagrangian to the $S$- and $P$-partial waves a satisfactory description of the phase shifts from the analysis of the Roy-Steiner equations is obtained. We predict the phase shifts for the $D$ and $F$ waves and compare them with the results of the analysis of the George Washington University group. The threshold parameters are calculated both in the delta-less and delta-full cases. Based on the determined low-energy constants, we discuss the pion-nucleon sigma term. Additionally, in ...
Energy Technology Data Exchange (ETDEWEB)
Garcia de Abajo, F.J. (Departamento de Ciencias de la Computacion e Inteligencia Artificial, Facultad de Informatica, Universidad del Pais Vasco, Apartado 649, 20080 San Sebastian (Spain)); Ponce, V.H.; Echenique, P.M. (Departamento de Fisica de Materiales, Facultad de Quimica, Universidad del Pais Vasco, Apartado 1072, 20080 San Sebastian (Spain))
1994-01-15
The resonant coherent interaction of an ion with an oriented crystal surface, under grazing-incidence conditions with respect to a special direction of the crystal, gives rise to electron loss to the continuum from electronic bound states of the ion. The calculations presented below predict large probabilities for electron emission due to this mechanism. The electrons are emitted with well defined energies, expressed in terms of the condition of resonance. Furthermore, the emission takes place around certain preferential directions, which are determined by both the latter condition and the symmetry of the surface lattice. Our calculations for MeV He[sup +] ions scattered at a W(001) surface along the [l angle]100[r angle] direction with glancing angle of 0--2 mrad indicate a yield of emission close to 1. Using heavier projectiles, one obtains smaller yields, but still large enough to be measurable in some cases (e.g., [approx]0.9 for 53 MeV B[sup 4+] and an angle of incidence of 1 mrad). Besides, the initial bound state is energy shifted due to the interaction with both the crystal potential and the velocity-dependent image potential. This results in a slight shift of the peaks of emission, which suggests a possible spectroscopy for analyzing the dynamical interaction of electronic bound states with solid surfaces.
Evidence for a New Resonance from Polarized Neutron-Proton Scattering
Adlarson, P; Bardan, W; Bashkanov, M; Bergmann, F S; Berlowski, M; Bhatt, H; Buescher, M; Ciepa, H Calen I; Clement, H; Coderre, D; Czerwinski, E; Demmich, K; Doroshkevich, E; Engels, R; Erven, A; Erven, W; Eyrich, W; Fedorets, P; Foehl, K; Fransson, K; Goldenbaum, F; Goslawski, P; Goswami, A; Grigoyev, K; Gullstroem, C -O; Hauenstein, F; Heijkenskjoeld, L; Hejny, V; Hodana, M; Hoistad, B; Huesken, N; Jany, A; Jany, B R; Jarczyk, L; Johansson, T; Kamys, B; Kemmerling, G; Khan, F A; Khoukaz, A; Kirrilov, D A; Kistryn, S; Kleines, H; Klos, B; Krapp, M; Krzemien, W; Kulessa, P; Kupsc, A; Lalwani, K; Lersch, D; Lorentz, B; Magiera, A; Maier, R; Marciniewski, P; Marianski, B; Mikirtychiants, M; Morsch, H -P; Moskal, P; Ohm, H; Ozerianska, I; del Rio, E Perez; Piskunov, N M; Podkopal, P; Prasuhn, D; Pricking, A; Pszczel, D; Pysz, K; Pysniak, A; Redmer, C F; Ritman, J; Roy, A; Rudy, Z; Sawant, S; Schadmand, S; Sefzick, T; Serdyuk, V; Siudak, R; Skorodko, T; Skurzok, M; Smyrski, J; Sopov, V; Stassen, R; Stepaniak, J; Stephan, E; Sterzenbach, G; Stockhorst, H; Stroeher, H; Szczurek, A; Taeschner, A; Trzcinski, A; Varma, R; Wagner, G J; Wolke, M; Wronska, A; Wuestner, P; Wurm, P; Yamamoto, A; Yurev, L; Zabierowski, J; Zielinski, M J; Zink, A; Zlomanczuk, J; Zupranski, P; Zurek, M; Workman, R L; Briscoe, W J; Strakovsky, I I
2014-01-01
Exclusive and kinematically complete high-statistics measurements of quasifree polarized $\\vec{n}p$ scattering have been performed in the energy region of the narrow resonance structure $d^*$ with $I(J^P) = 0(3^+)$, $M~\\approx$~2380~MeV/$c^2$ and $\\Gamma \\approx$ 70 MeV observed recently in the double-pionic fusion channels $pn \\to d\\pi^0\\pi^0$ and $pn \\to d\\pi^+\\pi^-$. The experiment was carried out with the WASA detector setup at COSY having a polarized deuteron beam impinged on the hydrogen pellet target and utilizing the quasifree process $\\vec{d}p \\to np + p_{spectator}$. That way the $np$ analyzing power $A_y$ was measured over a large angular range. The obtained $A_y$ angular distributions deviate systematically from the current SAID SP07 NN partial-wave solution. Incorporating the new $A_y$ data into the SAID analysis produces a pole in the $^3D_3 - ^3G_3$ waves as expected from the $d^*$ resonance hypothesis.
Fano resonance and the hidden order in URu2 Si 2 probed by quasiparticle scattering spectroscopy*
Park, W. K.; Greene, L. H.; Bauer, E. D.; Tobash, P. H.; Ronning, F.; Lu, X.; Sarrao, J. L.; Thompson, J. D.
2011-03-01
The nature of the hidden order transition occurring at 17.5 K in URu 2 Si 2 remains puzzling despite intensive investigations over the past two and half decades. Recent experimental and theoretical developments render it a timely subject to probe the hidden order state using quasiparticle tunneling and scattering techniques. We report on the Fano resonance in pure and Rh-doped URu 2 Si 2 single crystals using point-contact spectroscopy. The conductance spectra reproducibly reveal asymmetric double peak structures slightly off-centered around zero bias with the two peaks merging well above the hidden order transition temperature. An analysis using the Fano resonance model in a Kondo lattice [1] shows that the conductance peaks arise from the hybridization gap opening. Our estimated gap size agrees well with those reported from other measurements. We will present experimental results over a wide parameter space including temperature and doping dependences and discuss their underlying physics. M. Maltseva, M. Dzero, and P. Coleman, Phys. Rev. Lett. 103, 206402 (2009). * The work at UIUC is supported by the U.S. DOE under Award Nos. DE-FG02-07ER46453 and DE-AC02-98CH10886, and the work at LANL is carried out under the auspices of the U.S. DOE, Office of Science.
Leutenegger, Maurice A.; Owocki, Stanley P.; Kahn, Steven M.; Paerels, Frits B. S.
2006-01-01
We fit the Doppler profiles of the He-like triplet complexes of \\ion{O}{7} and \\ion{N}{6} in the X-ray spectrum of the O star $\\zeta$ Puppis, using XMM-Newton RGS data collected over $\\sim 400$ ks of exposure. We find that they cannot be well fit if the resonance and intercombination lines are constrained to have the same profile shape. However, a significantly better fit is achieved with a model incorporating the effects of resonance scattering, which causes the resonance line to become more...
International Nuclear Information System (INIS)
Calculations of elastic scattering angular distributions for reactions of the weakly bound projectile 6Li with targets 144Sm and 208Pb at energies above the barrier, are performed with the Continuum Discretized Coupled-Channel method (CDCC). Ground, resonant and nonresonant continuum states of 6Li are included up to some maximum energy εmax for which convergence is achieved. In the three-body system, global interactions are used for the α-target and d - target sub-systems. The effect of continuum resonant states of 6Li, i.e., l = 2, jπ = 3+, 2+ and 1+ on elastic scattering angular distributions is investigated by extracting these states from the continuum space. It is found that the calculated elastic scattering angular distributions are in good agreement with the measurements for most of the cases studied where consideration of couplings to continuum states is essential. It is also found that the resonance character of the continuum states is in some cases important to obtain agreement with the data
DEFF Research Database (Denmark)
Mortensen, Asger; Rønnow, Henrik Moodysson; Bruus, Henrik;
2000-01-01
The magnetic resonance at 41 meV observed in neutron scattering studies of YBa2Cu3O7 holds a key position in the understanding of high-T-c, superconductivity. Within the SO(5) model for superconductivity and antiferromagnetism, we have calculated the effect of an applied magnetic field on the neu...
In situ resonant Raman scattering and reversible photoinduced structural change in YBa2Cu3O6+x
DEFF Research Database (Denmark)
Osada, M.; Käll, M.; Bäckström, J.;
2005-01-01
or absence of a specific Raman scattering resonance. A comparison of the spectral efficiencies for this photoswitching with analogous data for the persistent photoconductivity and photoconductivity quenching effects suggests that the two phenomena have the same microscopic origin. We argue that the effects...
Schnitzer, Cheryl S.; Reim, Candace Lawson; Sirois, John J.; House, Paul G.
2010-01-01
Advanced chemistry students are introduced to surface-enhanced resonance Raman scattering (SERRS) by studying how sodium copper chlorophyllin (CuChl) adsorbs onto silver colloids (CuChl/Ag) as a function of pH. Using both SERRS and visible extinction spectroscopy, the extent of CuChl adsorption and colloidal aggregation are monitored. Initially at…
DEFF Research Database (Denmark)
Birkedal, Dan; Shah, Jagdeep; Pfeiffer, L. N.
1999-01-01
the coherent field associated with Rayleigh component using ultrafast spectral interferometry or Tadpole, thus, obtaining substantial and new information of the nature of resonant secondary emission. Our observation demonstrates that Rayleigh scattering from static disorder is inherently a non-ergodic process...
SOLUTION DYNAMICS BY LINE-SHAPE ANALYSIS, RESONANCE LIGHT-SCATTERING AND FEMTOSECOND 4-WAVE-MIXING
NIBBERING, ETJ; DUPPEN, K; WIERSMA, DA
1992-01-01
The results of line shape analysis, resonance light scattering and femtosecond four-wave mixing measurements are reported on several organic molecules in solution. It is shown that a Brownian oscillator model for line broadening provides a full description for the optical dynamics in aprotic solutio
Resonant magnetic x-ray scattering study of phase transitions in UPd[sub 2]Al[sub 3
Energy Technology Data Exchange (ETDEWEB)
Gaulin, B.D.; Gibbs, D.; Isaacs, E.D.; Lussier, J.G.; Reimers, J.N.; Schroeder, A.; Taillefer, L.; Zschack, P. (Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1 (Canada) Physics Department, Brookhaven, National Laboratory, Upton, New York 11973 (United States) AT T Bell Laboratories, Murray Hill, New Jersey 07973 (United States) Laboratoire Louis-Neel, Centre Nationale de la Recherche Scientifique, Grenoble (France) Oak Ridge Institute for Science and Education, Brookhaven National Laboratory, Upton, New York 11973 (United States))
1994-08-08
Resonant magnetic x-ray scattering measurements were performed on a single microcrystallite at the surface of a polycrystalline boule of the antiferromagnetic, heavy fermion superconductor UPd[sub 2]Al[sub 3]. These measurements show a strong anomaly in the order parameter at 11.8 K, below [ital T][sub [ital N
International Nuclear Information System (INIS)
Excitation functions have been measured for elastic scattering of polarized protons from 206Pb and 208Pb, and for inelastic scattering to collective states in 206Pb (2+, 0.8033 MeV; 3-, 2.647 MeV) and 208Pb (3-, 2.6145 MeV). Both differential cross sections and analyzing powers were measured at theta/sub lab/ = 1200, 1350, 1500, and 1650, for E/sub p/ = 14.25 to 18 MeV. Fits to the excitation-function data were obtained using scattering amplitudes consisting of sums of resonant and non-resonant parts. The resonances are the isobaric analogs (IARs) of 7 low-lying states in 209Pb and 35 in 207Pb. The fits to the elastic-scattering data are excellent; for the inelastic scattering the fit is very good for the 2+ state but only fair for the 3- states. For each IAR, the energy, the total width, and the partial width and mixing phase in each channel were obtained. Also, new spin assignments were made for a number of parent states in 207Pb. The theory of Bund and Blair was used to find the spectroscopic amplitudes, which provide information on the wave functions for the parent states in 207Pb and 209Pb and for the 3- states in 206Pb and 208Pb. These spectroscopic amplitudes were then checked for internal consistency and compared with the results of other experiments and with theoretical predictions
The first direct measurement of 12C(12C,n)23Mg at stellar energies
Bucher, B; Fang, X; Heger, A; Almaraz-Calderon, S; Alongi, A; Ayangeakaa, A D; Beard, M; Best, A; Browne, J; Cahillane, C; Couder, M; deBoer, R J; Kontos, A; Lamm, L; Li, Y J; Long, A; Lu, W; Lyons, S; Notani, M; Patel, D; Paul, N; Pignatari, M; Roberts, A; Robertson, D; Smith, K; Stech, E; Talwar, R; Tan, W P; Wiescher, M; Woosley, S E
2015-01-01
Neutrons produced by the carbon fusion reaction 12C(12C,n)23Mg play an important role in stellar nucleosynthesis. However, past studies have shown large discrepancies between experimental data and theory, leading to an uncertain cross section extrapolation at astrophysical energies. We present the first direct measurement that extends deep into the astrophysical energy range along with a new and improved extrapolation technique based on experimental data from the mirror reaction 12C(12C,p)23Na. The new reaction rate has been determined with a well-defined uncertainty that exceeds the precision required by astrophysics models. Using our constrained rate, we find that 12C(12C,n)23Mg is crucial to the production of Na and Al in Pop-III Pair Instability Supernovae. It also plays a non-negligible role in the production of weak s-process elements as well as in the production of the important galactic gamma-ray emitter 60Fe.
International Nuclear Information System (INIS)
In the nucleus 208Pb giant multipole resonances up to excitation energies of Esub(x) = 35 MeV were looked for by medium resolution inelastic electron scattering. Twelve spectra were taken up at incident energies of E0 = 45-65 MeV under scattering angles from upsilon = 930 to 1650. The cross sections extracted from this were analyzed by means of DWBA calculations using RPA amplitudes from a model with separable residual interaction. On the base of this analysis for the first time it could be shown that the maximum in the electron scattering cross section at Esub(x) approx.= 14 MeV can be consistently described as superposition of the Jsup(π) = 1-, ΔT = 1 with a Jsup(π) = 0+, ΔT = 0 giant resonance. Furthermore the spectra under backward scattering angles indicate the existence of a magnetic excitation at Esub(x) approx.= 15 MeV which is interpreted as Jsup(π) = 3+ giant resonance. Besides under forward angles a further weak excitation at Esub(x) approx.= 14.6 MeV appears which is very well compatible with Jsup(π) = 2+. At Esub(x) = 17.5 MeV a Jsup(π) = 3- resonance was found which recently is observed also in (α, α') experiments and therefore gets a ΔT = 0 assignment. A further resonance at Esub(x) approx.= 21 MeV has also a Jsup(π) = 3- character but has to be partly assigned to a Jsup(π) = 1-, ΔT = 0 excitation. At Esub(x) = 23.8 MeV a Jsup(π) = 2+ excitation was found which gets because of model predictions a ΔT = 1 assignment. (orig./HSI)
Kuraptsev, A. S.; Sokolov, I. M.; Fofanov, Ya. A.
2016-03-01
We analyze resonant light scattering from a dense and disordered ensemble of motionless point-like scatters with uniform (on average) spatial distribution of the density. The average interatomic distance is considered comparable with the resonant wavelength and the mean free path of photon. The inhomogeneity of dipole-dipole interaction near the surface is discussed. Angular distribution of the light scattered from a medium in a slab geometry is calculated. The total reflected light power P and the reflectivity R depending on the optical thickness of a medium bz are analyzed. It is shown that in the case of small optical thickness (bz ≪ 1) P(bz) ∝ bz2 and R(bz) ∝ bz. With further increasing of the optical thickness we observe oscillations of the dependencies P(bz) and R(bz). The attenuation coefficient of these oscillations is discussed.
Scattering resonance of elastic wave and low-frequency equivalent slow wave
Meng, X.; Liu, H.; Hu, T.; Yang, L.
2015-12-01
Transmitted wave occurs as fast p-wave and slow p-wave in certain conditions when seismic waves travel through inhomogeneous layers. Energy of slow p-waves is strongest at some frequency band, but rather weak at both high frequency band and low frequency band, called scattering resonance. For practical seismic exploration, the frequency of slow p-wave occurs is below 10Hz, which cannot be explained by Biot's theory which predicts existence of the slow p-wave at ultrasonic band in the porous media. The slow p-wave equation have been derived, but which only adapted to explaining slow p-wave in the ultrasonic band. Experimental observations exhibit that slow p-wave also exists in nonporous media but with enormous low-velocity interbeds. When vertical incidence, elastic wave is simplified as compressing wave, the generation of slow waves is independent on shear wave. In the case of flat interbed and gas bubble, Liu (2006) has studied the transmission of acoustic waves, and found that the slow waves below the 10Hz frequency band can be explained. In the case of general elastic anisotropy medium, the tiheoretical research on the generation of slow waves is insufficient. Aiming at this problem, this paper presents an exponential mapping method based on transmitted wave (Magnus 1954), which can successfully explain the generation of the slow wave transmission in that case. Using the prediction operator (Claerbout 1985) to represent the transmission wave, this can be derived as first order partial differential equation. Using expansions in the frequency domain and the wave number domain, we find that the solutions have different expressions in the case of weak scattering and strong scattering. Besides, the method of combining the prediction operator and the exponential map is needed to extend to the elastic wave equation. Using the equation (Frazer and Fryer 1984, 1987), we derive the exponential mapping solution for the prediction operator of the general elastic medium
Electroweak coupling measurements from polarized Bhabha scattering at the Z{sup 0} resonance
Energy Technology Data Exchange (ETDEWEB)
Pitts, K.T.
1994-03-01
The cross section for Bhabha scattering (e{sup +}e{sup {minus}} {yields} e{sup +}e{sup {minus}}) with polarized electrons at the center of mass energy of the Z{sup 0} resonance has been measured with the SLD experiment at the Stanford Linear Accelerator Center during the 1992 and 1993 runs. The electroweak couplings of the electron are extracted. At small angles the measurement is done in the SLD Silicon/Tungsten Luminosity Monitor (LMSAT). A detailed description of the design, construction, commissioning and operation of the LMSAT is provided. The integrated luminosity for 1992 is measured to be L = 420.86{plus_minus}2.56 (stat){plus_minus}4.23 (sys) nb{sup {minus}1}. The luminosity asymmetry for polarized beams is measured to be A{sub LR}(LUM) = (1.7 {plus_minus} 6.4) {times} 10{sup {minus}3}. The large angle polarized Bhabha scattering reveals the effective electron vector and axial vector couplings to the Z{sup 0} through the measurement of the Z{sup 0} {yields} e{sup +}e{sup {minus}} partial width, {Gamma}{sub ee}, and the parity violation parameter, A{sub e}. From the combined 1992 and 1993 data the effective electron vector and axial vector couplings are measured to be {bar g}{sub v}{sup e} = {minus}0.0495{plus_minus}0.0096{plus_minus}0.0030, and {bar g}{sub {alpha}}{sup e} = {minus}0.4977{plus_minus}0.0035{plus_minus}0.0064 respectively. The effective weak mixing angle is measured to be sin{sup 2}{theta}{sub W}{sup eff} = 0.2251{plus_minus}0.0049{plus_minus}0.0015. These results are compared with other experiments.
Institute of Scientific and Technical Information of China (English)
YI,Ao-Er; LIU,Zhong-Fang; LIU,Shao-Pu; KONG,Ling
2008-01-01
In pH 5.0-5.4 HOAc-NaOAc buffer solution, clindamycin (Clin) could react with Pd(II) to form a 1 : 1 cati-onic chelate, which could further react with halofluorescein dyes such as diiodofluorescein (DIP), erythrosine (Ery) and eosin Y (EY) to form 1:1 ion-association complexes. As a result, not only the absorption and fluorescence spectra were changed, but also the resonance Rayleigh scattering (RRS) intensities enhanced greatly and new RRS spectra appeared. The three reaction products had characteristic RRS spectra and their maximum RRS wavelengths were located at 285 (DIP system), 287 (Ery system) and 321 (EY system) nm, respectively. The scattering intensities were proportional to the concentration of Clin in certain range which could be applied to determine Clin. The linear ranges and detection limits of Clin were 0.025-2.1μg·mL-1 and 7.8 ng·mL-1 for the DIP system, 0.053-2.4μg·mL-1 and 16.0 ng·mL-1 for the Ery system, 0.038-2.4μg·mL-1 and 11.0 ng·mL-1 for the EY system, respectively. In this work, the optimum reaction conditions and the foreign substances were investigated. A simple, sensitive and fast method was developed for the determination of Clin either in the pharmaceutical form or in the human body fluid. Moreover, the composition, structure, reaction mechanism of the ternary complexes and their effects on the absorption, fluorescence and RRS spectra as well as the reasons of RRS enhancement were discussed.
Arsenic speciation by X-ray spectroscopy using resonant Raman Scattering
Energy Technology Data Exchange (ETDEWEB)
Sanchez, H.J.; Leani, J.J. [Universidad Nacional de Cordoba, Cba (Argentina); Perez, C.A. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil)
2012-07-01
Full text: The toxicity of arsenic species is widely known. A realistic evaluation of the risk posed by As depends on accurate determination of As speciation, because its toxicity and mobility varies with oxidation state and chemical environment. The most toxic species are inorganic As (III) and As (V) called respectively arsenite or trivalent arsenic, and arsenate or pentavalent arsenic. Recently, x-ray Resonant Raman Scattering spectroscopy has been successfully employed to determine the oxidation state of metals. In this work we use RRS spectroscopy to perform arsenic speciation. The measurements were carried out in XRF station of the D09B-XRF beamline at the Brazilian synchrotron facility (LNLS, Campinas). Mineral samples of As in different oxidation states (As(III) and AS(V)), and two biological forms of arsenic (monomethylarsonic acid (MMA(V) and dimethylarsinic acid DMA(V)) were analysed. The samples were diluted, deposited on silicon wafers and allowed to dry. The amount of liquid deposited on the reflector before evaporation was 20 microliters for all the specimens. These samples were irradiated with monochromatic photons of 11816 eV, i.e., below the K-edge of arsenic in order to inspect the Raman emissions. The measuring lifetime was 3600 sec for each sample. Spectra were analysed with specific programs for spectrum analysis using non-conventional functions for data fitting, i.e., modified Voight functions (for Compton peaks), Gaussian functions for fluorescent and for low intensity peaks (such as escape peaks and other contributions), and polynomial functions for the background. Raman peaks were fitted using specific functions. In this work we have shown that resonant Raman scattering spectroscopy can be used to analyse arsenic species. The method is very simple and reliable. The most important feature of this method relies in the possibility of using the same spectrometer of XRF analysis or TXRF analysis. In this way, practically in the same experiment
Structure of the Hoyle State in 12C
International Nuclear Information System (INIS)
The first excited 0+ state in 12C (Hoyle state) has been predicted to be a dilute self-bound gas of bosonic α particles, similar to a Bose-Einstein condensate. To clarify this conjecture, precise electron scattering data on form factors of the ground state and the transition to the Hoyle state are compared with results of the fermionic molecular dynamics model, a microscopic α-cluster model, and an α-cluster model with reduced degrees of freedom (in the spirit of a Bose-Einstein condensed state). The data indicate clearly a dilute density with a large spatial extension of the Hoyle state. A closer inspection of the model calculations, which reproduce the experimental findings, reveals that the term Bose-Einstein condensation of three α particles must not be taken too literally
Energy Technology Data Exchange (ETDEWEB)
Laveissiere, Geraud; Degrande, Natalie; Jaminion, Stephanie; Jutier, Christophe; Todor, Luminita; Di Salvo, Rachele; Van Hoorebeke, L.; Alexa, L.C.; Anderson, Brian; Aniol, Konrad; Arundell, Kathleen; Audit, Gerard; Auerbach, Leonard; Baker, F.; Baylac, Maud; Berthot, J.; Bertin, Pierre; Bertozzi, William; Bimbot, Louis; Boeglin, Werner; Brash, Edward; Breton, Vincent; Breuer, Herbert; Burtin, Etienne; Calarco, John; Cardman, Lawrence; Cavata, Christian; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chen, Jian-Ping; Chudakov, Eugene; Cisbani, Evaristo; Dale, Daniel; De Jager, Cornelis; De Leo, Raffaele; Deur, Alexandre; D' Hose, Nicole; Dodge, Gail; Domingo, John; Elouadrhiri, Latifa; Epstein, Martin; Ewell, Lars; Finn, John; Fissum, Kevin; Fonvieille, Helene; Fournier, Guy; Frois, Bernard; Frullani, Salvatore; Furget, Christophe; Gao, Haiyan; Gao, Juncai; Garibaldi, Franco; Gasparian, Ashot; Gilad, Shalev; Gilman, Ronald; Glamazdin, Oleksandr; Glashausser, Charles; Gomez, Javier; Gorbenko, Viktor; Grenier, Philippe; Guichon, Pierre; Hansen, Jens-Ole; Holmes, Richard; Holtrop, Maurik; Howell, Calvin; Huber, Garth; Hyde, Charles; Incerti, Sebastien; Iodice, Mauro; Jardillier, Johann; Jones, Mark; Kahl, William; Kamalov, Sabit; Kato, Seigo; Katramatou, A.T.; Kelly, James; Kerhoas, Sophie; Ketikyan, Armen; Khayat, Mohammad; Kino, Kouichi; Kox, Serge; Kramer, Laird; Kumar, Krishna; Kumbartzki, Gerfried; Kuss, Michael; Leone, Antonio; LeRose, John; Liang, Meihua; Lindgren, Richard; Liyanage, Nilanga; Lolos, George; Lourie, Robert; Madey, Richard; Maeda, Kazushige; Malov, Sergey; Manley, D.; Marchand, Claude; Marchand, Dominique; Margaziotis, Demetrius; Markowitz, Pete; Marroncle, Jacques; Martino, Jacques; McCormick, Kathy; McIntyre, Justin; Mehrabyan, Surik; Merchez, Fernand; Meziani, Zein-Eddine; Michaels, Robert; Miller, Gerald; Mougey, Jean; Nanda, Sirish; Neyret, Damien; Offermann, Edmond; Papandreou, Zisis; Perdrisat, Charles; Perrino, R.; Petratos, Gerassimos; Platchkov, Stephane; Pomatsalyuk, Roman; Prout, David; Punjabi, Vina; Pussieux, Thierry; Quemener, Gilles; Ransome, Ronald; Ravel, Oliver; Real, Jean-Sebastien; Renard, F.; Roblin, Yves; Rowntree, David; Rutledge, Gary; Rutt, Paul; Saha, Arunava; Saito, Teijiro; Sarty, Adam; Serdarevic, A.; Smith, T.; Smirnov, G.; Soldi, K.; Sorokin, Pavel; Souder, Paul; Suleiman, Riad; Templon, Jeffrey; Terasawa, Tatsuo; Tiator, Lothar; Tieulent, Raphael; Tomasi-Gustaffson, E.; Tsubota, Hiroaki; Ueno, Hiroaki; Ulmer, Paul; Urciuoli, Guido; Van De Vyver, R.; van der Meer, Rob; Vernin, Pascal; Vlahovic, B.; Voskanyan, Hakob; Voutier, Eric; Watson, J.W.; Weinstein, Lawrence; Wijesooriya, Krishni; Wilson, R.; Wojtsekhowski, Bogdan; Zainea, Dan; Zhang, Wei-Ming; Zhao, Jie; Zhou, Z.-L.
2009-01-01
We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e,e'p)? exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the W-dependence at fixed Q2=1 GeV2, and for the Q2-dependence at fixed W near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q2-dependence is smooth. The measured ratio of H(e,e'p)? to H(e,e'p)?0 cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data at the highest W (1.8-1.9 GeV) show a striking Q2-independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.
International Nuclear Information System (INIS)
Graphical abstract: Raman scattering (RS) of light by crystals was studied theoretically taking into account the electron-electron and electron-phonon interactions. The partial diagonalization of the Hamiltonian using unitary transformation was fulfilled. It allowed the structure of the many phonon repetition of bands to be described as a function of the electron-phonon interaction constant. It is shown that the spectral relations obtained for the scattering intensity can describe both the RS and the resonance RS (RRS) processes. Numerical modelling calculations for different parameters were carried out and comparisons with the experimental data for CdS and ZnO crystals were made. Highlights: → Raman scattering of light by crystals studied theoretically. → Electron-electron and electron-phonon interactions taken into account. → Structure of many phonon repetition of bands described. → Both Raman and resonance Raman scattering covered. → Comparisons with experimental data for CdS and ZnO crystals. - Abstract: Raman scattering (RS) of light by crystals was studied theoretically taking into account the electron-electron and electron-phonon interactions. The partial diagonalization of the Hamiltonian using unitary transformation was fulfilled. It allowed the structure of the many phonon repetition of bands to be described as a function of the electron-phonon interaction constant. It is shown that the spectral relations obtained for the scattering intensity can describe both the RS and the resonance RS (RRS) processes. Numerical modelling calculations for different parameters were carried out and comparisons with the experimental data for CdS and ZnO crystals were made.
Resonant Raman and micro-Raman scattering from Si matrix with unburied beta-FeSi2 nanolayers.
Marinova, M; Baleva, M; Zlateva, G
2008-02-01
Samples, representing Si matrix with nanolayers of the semiconducting beta-FeSi2 silicide are studied by Raman scattering. The unpolarized Raman spectra of the samples are measured in two different configurations. It is found that the characteristic beta-FeSi2 Raman modes are seen in the spectra, taken at incident angle of about 45 degrees , while only comparatively intensive broad feature is detected in a back-scattering geometry. The difference in the spectra is interpreted with the appearance of surface polariton modes of the optical phonons in the nanosized layers in near back-scattering geometry. The resonant Raman scattering is investigated at incident light angle of about 45 degrees and the energies of the interband transitions in the investigated energy range are determined. It is known that the resonant Raman scattering appears to be even more precise method for the determination of the interband transitions energies than the modulation spectroscopy. Thus we claim that the energies determined here are firstly determined with such a precision. PMID:18464405
Li, Qin; Tan, Xuanping; Zheng, Xiaobo; Tang, Weiwei; Yang, Jidong
2015-11-01
A novel resonance Rayleigh scattering method was developed for the determination of fast green (FCF) in grape wine. In pH 2.5 Britton Robinson (BR) buffer solution, the scattering signal of acridine orange (AO) was remarkably enhanced after adding trace amount of FCF and forming an ion-association complex, which not only resulted in the change of absorption spectrum, fluorescence spectra, but also led to a significant enhancement of resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS), and second order scattering (SOS). The linear ranges and detection limits for RRS, SOS and FDS were 2-45 × 10-6 mol L-1, 2-24 × 10-6 mol L-1, 2-20 × 10-6 mol L-1, and 8.0 × 10-8 mol L-1, 4.7 × 10-7 mol L-3, 1.0 × 10-7 mol L-3, respectively. In this work, the optimum conditions, the influencing factors and the effects of coexisting substances on the reaction were investigated. The method can be applied to the determination of FCF in grape wine and the results were satisfactory.
α-clustering effects in dissipative 12C + 12C reactions at 95 MeV
Baiocco, G.; Morelli, L.; Gulminelli, F.; D'Agostino, M.; Bruno, M.; Abbondanno, U.; Barlini, S.; Bini, M.; Carboni, S.; Casini, G.; Cinausero, M.; Degerlier, M.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Raduta, Ad. R.
2013-05-01
Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at Laboratori Nazionali di Legnaro. A comparison to a dedicated Hauser-Feshbach calculation allows us to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from statistical behavior are observed in α yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for six-α decay.
\\alpha-clustering effects in dissipative 12C+12C reactions at 95 MeV
Baiocco, G; Gulminelli, F; D'Agostino, M; Bruno, M; Abbondanno, U; Barlini, S; Bini, M; Carboni, S; Casini, G; Cinausero, M; Gramegna, M Degerlier F; Kravchuk, V L; Marchi, T; Olmi, A; Pasquali, G; Piantelli, S; Raduta, Ad R
2013-01-01
Dissipative 12C+12C reactions at 95 MeV are fully detected in charge with the GARFIELD and RCo apparatuses at LNL. A comparison to a dedicated Hauser-Feshbach calculation allows to select events which correspond, to a large extent, to the statistical evaporation of highly excited 24Mg, as well as to extract information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain. Residual deviations from a statistical behaviour are observed in \\alpha yields and attributed to the persistence of cluster correlations well above the 24Mg threshold for 6 \\alpha's decay.
Hydride generation-resonance Rayleigh scattering and SERS spectral determination of trace Bi.
Liang, Xiaojing; Wen, Guiqing; Liu, Qingye; Liang, Aihui; Jiang, Zhiliang
2016-09-01
In acidic solutions, Bi(III) was reduced by NaBH4 to form BiH3 gas. Using I3(-)graphene oxide (GO) as absorption solution, the BiH3 gas reacted with I3(-) to form I(-) that resulted in the I3(-) concentration decreasing. In the absence of BiH3, the I3(-) concentration was high, and as receptors it was closed to the surfaces of GO which was as donors. Then the surface plasmon resonance Rayleigh scattering (RRS) energy of GO transfers to I3(-) heavily, and results in the RRS quenching severely. With the increase of the Bi(III) concentration, the receptors and the RRS energy transfer (RRS-ET) decreased, so the RRS intensity enhanced linearly at 370nm. The RRS intensity was linear to the Bi(III) concentration in 0.05-5.5μmol/L, with a detection limit of 4ng/mL Bi. A new RRS-ET spectral method was developed for the determination of trace Bi(III). Using I3(-) as the absorption solution, silver nanorod (AgNR) as sol substrate and Vitoria blue B (VBB) as molecular probe, a SERS method was developed for detection of Bi. PMID:27214274
Central Elemental Abundance Ratios in the Perseus Cluster Resonant Scattering or SN Ia Enrichment?
Dupke, R A; Dupke, Renato A.; Arnaud, Keith A.
2001-01-01
We have determined elemental abundance ratios in the core of the Perseus cluster for several elements. These ratios indicate a central dominance of SN Ia ejecta similar to that found for A496, A2199 and A3571 (Dupke & White 2000). Simultaneous analysis of ASCA spectra from SIS1, GIS 2&3 shows that the ratio of Ni to Fe abundances is ~ (3.4 +- 1.1) times Solar within the central 4'. This ratio is consistent with (and more precise than) that observed in other clusters whose central regions are dominated by SN Ia ejecta. Such a large Ni over-abundance is predicted by "Convective Deflagration" explosion models for SN Ia such as "W7" but is inconsistent with delayed detonation models. We note that with current instrumentation the NiK(alpha) line is confused with FeK(beta) and that the Ni over-abundance we observe has been interpreted by others as an anomalously large ratio of FeK(beta) to FeK(alpha) caused by resonant scattering in the FeK(alpha) line. We argue that a central enhancement of SN Ia ejecta an...
Huang, H Y; Jia, C J; Chen, Z Y; Wohlfeld, K; Moritz, B; Devereaux, T P; Wu, W B; Okamoto, J; Lee, W S; Hashimoto, M; He, Y; Shen, Z X; Yoshida, Y; Eisaki, H; Mou, C Y; Chen, C T; Huang, D J
2016-01-01
Measurements of spin excitations are essential for an understanding of spin-mediated pairing for superconductivity; and resonant inelastic X-ray scattering (RIXS) provides a considerable opportunity to probe high-energy spin excitations. However, whether RIXS correctly measures the collective spin excitations of doped superconducting cuprates remains under debate. Here we demonstrate distinct Raman- and fluorescence-like RIXS excitations of Bi1.5Pb0.6Sr1.54CaCu2O(8+δ). Combining photon-energy and momentum dependent RIXS measurements with theoretical calculations using exact diagonalization provides conclusive evidence that the Raman-like RIXS excitations correspond to collective spin excitations, which are magnons in the undoped Mott insulators and evolve into paramagnons in doped superconducting compounds. In contrast, the fluorescence-like shifts are due primarily to the continuum of particle-hole excitations in the charge channel. Our results show that under the proper experimental conditions RIXS indeed can be used to probe paramagnons in doped high-Tc cuprate superconductors. PMID:26794437
Zhang, Weiai; Ma, Caijuan; Su, Zhengquan; Bai, Yan
2016-11-01
This paper describes a highly sensitive and accurate approach using aniline blue (AB) (water soluble) as a probe to determine chitosan (CTS) through Resonance Rayleigh scattering (RRS). Under optimum experimental conditions, the intensities of RRS were linearly proportional to the concentration of CTS in the range from 0.01 to 3.5μg/mL, and the limit of detection (LOD) was 6.94ng/mL. Therefore, a new and highly sensitive method based on RRS for the determination of CTS has been developed. Furthermore, the effect of molecular weight of CTS and the effect of the degree of deacetylation of CTS on the accurate quantification of CTS was studied. The experimental data was analyzed by linear regression analysis, which indicated that the molecular weight and the degree of deacetylation of CTS had no statistical significance and this method could be used to determine CTS accurately. Meanwhile, this assay was applied for CTS determination in health products with satisfactory results. PMID:27294549
Variations in the Cyclotron Resonant Scattering Features during 2011 outburst of 4U 0115+63
Iyer, N; Dewangan, G C; Bhattacharya, D; Seetha, S
2015-01-01
We study the variations in the Cyclotron Resonant Scattering Feature (CRSF) during 2011 outburst of the high mass X-ray binary 4U 0115+63 using observations performed with Suzaku, RXTE, Swift and INTEGRAL satellites. The wide-band spectral data with low energy coverage allowed us to characterize the broadband continuum and detect the CRSFs. We find that the broadband continuum is adequately described by a combination of a low temperature (kT ~ 0.8 keV) blackbody and a power-law with high energy cutoff (Ecut ~ 5.4 keV) without the need for a broad Gaussian at ~ 10 keV as used in some earlier studies. Though winds from the companion can affect the emission from the neutron star at low energies (< 3 keV), the blackbody component shows a significant presence in our continuum model. We report evidence for the possible presence of two independent sets of CRSF lines with fundamentals at ~ 11 keV and ~ 15 keV. These two sets of CRSF lines could arise from spatially distinct emitting regions. We also find evidence ...
Extracting the resonance parameters from experimental data on scattering of charged particles
Vaandrager, P
2016-01-01
A new parametrization of the multi-channel S-matrix is used to fit scattering data and then to locate the resonances as its poles. The S-matrix is written in terms of the corresponding "in" and "out" Jost matrices which are expanded in the Taylor series of the collision energy E around an appropriately chosen energy E0. In order to do this, the Jost matrices are written in a semi-analytic form where all the factors (involving the channel momenta and Sommerfeld parameters) responsible for their "bad behaviour" (i.e. responsible for the multi-valuedness of the Jost matrices and for branching of the Riemann surface of the energy) are given explicitly. The remaining unknown factors in the Jost matrices are analytic and single-valued functions of the variable E and are defined on a simple energy plane. The expansion is done for these analytic functions and the expansion coefficients are used as the fitting parameters. The method is tested on a two-channel model, using a set of artificially generated data points wi...
Probing a scattering resonance in Rydberg molecules with a Bose-Einstein condensate
Schlagmüller, Michael; Nguyen, Huan; Lochead, Graham; Engel, Felix; Böttcher, Fabian; Westphal, Karl M; Kleinbach, Kathrin S; Löw, Robert; Hofferberth, Sebastian; Pfau, Tilman; Pérez-Ríos, Jesús; Greene, Chris H
2015-01-01
We present spectroscopy of a single Rydberg atom excited within a Bose-Einstein condensate. We not only observe the density shift as discovered by Amaldi and Segre in 1934, but a line shape which changes with the principal quantum number n. The line broadening depends precisely on the interaction potential energy curves of the Rydberg electron with the neutral atom perturbers. In particular, we show the relevance of the triplet p-wave shape resonance in the Rydberg electron-Rb(5S) scattering, which significantly modifies the interaction potential. With a peak density of 5.5x10^14 cm^-3, and therefore an inter-particle spacing of 1300 a0 within a Bose-Einstein condensate, the potential energy curves can be probed at these Rydberg ion - neutral atom separations. We present a simple microscopic model for the spectroscopic line shape by treating the atoms overlapped with the Rydberg orbit as zero-velocity, uncorrelated, point-like particles, with binding energies associated with their ion-neutral separation, and ...
Xiang, Haiyan; Dai, Kaijin; Luo, Qizhi; Duan, Wenjun; Xie, Yang
2011-01-01
A novel resonance light scattering (RLS) method was developed for the determination of resveratrol based on the interaction between resveratrol and methylene blue (MB). It was found that at pH 8.69, the weak RLS intensity of MB was remarkably enhanced by the addition of trace amount of resveratrol with the maximum peak located at 385.0 nm. Under the optimum conditions, a good linear relationship between the enhanced RLS intensities and the concentrations of resveratrol was obtained over the range of 2.0-14.0 μg ml -1 with the detection limit (3 σ) of 0.63 μg ml -1. The results of the analysis of resveratrol in synthetic samples and human urine are satisfactory, which showed it may provide a more sensitive, convenient, rapid and reproducible method for the detection of resveratrol, especially in biological and pharmaceutical field. In this work, the characteristics of RLS, absorption and fluorescence spectra of the resveratrol-MB system, the influencing factors and the optimum conditions of the reaction were investigated.
High-resolution resonant inelastic soft X-ray scattering applied to liquids
Energy Technology Data Exchange (ETDEWEB)
Rubensson, Jan-Erik, E-mail: jan-erik.rubensson@fysik.uu.se [Department of Physics and Astronomy, Uppsala University, Box 516, S-751 20 Uppsala (Sweden); Hennies, Franz [Department of Physics and Astronomy, Uppsala University, Box 516, S-751 20 Uppsala (Sweden); MAX-lab, Lund University, Box 118, S-221 00 Lund (Sweden); Pietzsch, Annette [MAX-lab, Lund University, Box 118, S-221 00 Lund (Sweden)
2013-06-15
Highlights: ► Vibrational excitations in liquids resolved in RIXS are observed. ► Soft vibrational modes are quenched in the RIXS process. ► Intermolecular dipole–dipole interaction influences spectral features. ► Influence of room temperature is excitations observed. -- Abstract: The brilliance of modern synchrotron radiation sources and capabilities of new instrumentation facilitate resonant inelastic soft X-ray scattering of liquids and molecular materials with high spectral quality. Especially, when the energy resolution approaches the natural line widths a detailed analysis provides information about local potential surfaces, dynamic coupling between nuclear and electronic degrees of freedom, and intermolecular interactions. After briefly commenting on various sample handling systems we review the recent high-resolution RIXS results on liquid acetone. The experimental RIXS spectra excited at the O K edge demonstrate that the CO stretching mode dominates the vibrational progressions, and that softer modes are little affected by the nuclear dynamics in the intermediate state. It is shown that intermolecular coupling can be neglected in this specific case, and it is predicted that such interaction significantly broadens spectral features in liquids with larger dipole–dipole interaction. Analysis of the data further shows that initial state thermal excitations at room temperature have a noticeable influence on the spectral features.
Solution Properties of Mixed Starch/Chitosan Revealed by Resonance Light Scattering
Institute of Scientific and Technical Information of China (English)
HU Yong; FU Xiong; CHEN Xu-dong; ZHONG Nan-jing
2012-01-01
The association behavior of starch and chitosan and the dilute solution properties of the starch/chitosan complex were investigated by means of resonance light scattering(RLS) spectra.The interaction between starch and chiotsan was proved by RLS.Based on the results,the appropriate association condition was selected.However,the solution property of starch/ehitosan was affected greatly by external factors such as pH value and metal ionic strength.The change of pH,which causes the irreversible transition of solution from transparent into murky,provides some important information of partitioning behavior of the complex in solution.The durative enhancement of RLS intensity for the complex exhibited two inflexions and a plateau in the presence of a certain amount of Fe3+.It indicates that Fe3+ not only increases the RLS intensity,but also induces the micell-aggregate transition of the complex in solution.Moreover,the thermodynamic parameters for micell formation process at different temperatures,based on the RLS values,were calculated.
Probing an Electron Scattering Resonance using Rydberg Molecules within a Dense and Ultracold Gas.
Schlagmüller, Michael; Liebisch, Tara Cubel; Nguyen, Huan; Lochead, Graham; Engel, Felix; Böttcher, Fabian; Westphal, Karl M; Kleinbach, Kathrin S; Löw, Robert; Hofferberth, Sebastian; Pfau, Tilman; Pérez-Ríos, Jesús; Greene, Chris H
2016-02-01
We present spectroscopy of a single Rydberg atom excited within a Bose-Einstein condensate. We not only observe the density shift as discovered by Amaldi and Segrè in 1934, but a line shape that changes with the principal quantum number n. The line broadening depends precisely on the interaction potential energy curves of the Rydberg electron with the neutral atom perturbers. In particular, we show the relevance of the triplet p-wave shape resonance in the e^{-}-Rb(5S) scattering, which significantly modifies the interaction potential. With a peak density of 5.5×10^{14} cm^{-3}, and therefore an interparticle spacing of 1300 a_{0} within a Bose-Einstein condensate, the potential energy curves can be probed at these Rydberg ion-neutral atom separations. We present a simple microscopic model for the spectroscopic line shape by treating the atoms overlapped with the Rydberg orbit as zero-velocity, uncorrelated, pointlike particles, with binding energies associated with their ion-neutral separation, and good agreement is found. PMID:26894707
Liang, Aihui; Wang, Yaohui; Wen, Guiqing; Zhang, Xinghui; Luo, Yanghe; Jiang, Zhiliang
2016-04-15
The stable silver nanorod (AgNR) sol in red was prepared by the two-step procedure of NaBH4-H2O2 and citrate heating reduction, and it exhibited a strong resonance Rayleigh scattering (RRS) peak at 346 nm. In pH 3.8 HAc-NaAc buffer solution, tea polyphenols (TP) reacted with ammonium molybdate (AM) to form yellow organic molybdate (OM) as receptor that was closed to the donor of AgNR, the RRS energy transfer (RRS-ET) takes place, owing to the overlapping between the AgNR RRS spectra and OM absorption spectra. When TP concentration increased, the RRS intensity decreased due to the RRS-ET increasing. So, a simple and sensitive AgNR surface plasmon RRS-ET analytical platform was fabricated to detect trace TP in the range of 0.05-0.85 μg/mL, with a detection limit of 0.03 μg/mL TP. The TP in tea samples was analyzed by this RRS-ET analysis platform, with satisfactory results.
Study of 22Al radioactivity and spectroscopy by resonant elastic scattering
International Nuclear Information System (INIS)
This thesis describes two studies which explore the structure of proton-rich nuclei. The first of these concerned an investigation of the β-delayed charged particle decay of 22Al. The experiment was carried out using the LISE3 spectrometer at GANIL and permitted the energies of the β-p, β-2p and β-α transitions together with the corresponding branching ratios to be determined with an improved precision over earlier work. In addition the coincidences with γ-rays were measured for the first time allowing the decay scheme to be reconstructed. Comparison with shell model calculations using the code OXBASH and the mirror nucleus 22F allowed the spin and parity and the mass of 22Al g.s. as well as levels in 22Mg to be deduced. The experimentally determined Gamow-Teller strength was found to be in good agreement at low excitation energies with a shell model calculation employing an effective operator. The second study concerned the development of resonant elastic scattering in inverse kinematics as a spectroscopic tool. Extensive simulations were carried out to ascertain the feasibility of such experiments as well as to optimise the set-up. In the context of the later, particular attention was paid to the final resolution. Experiments subsequently undertaken at GANIL with stable and radioactive beams demonstrated that the technique will be a powerful spectroscopic tool for use with radioactive beams with characteristics similar to those that will be furnished by SPIRAL. (author)
Institute of Scientific and Technical Information of China (English)
HE Youqiu; LIU Shaopu; LIU Qin; LIU Zhongfang; HU Xiaoli
2005-01-01
The interaction between gold nanoparticle and safranine T (ST) has been studied with resonance Rayleigh scattering (RRS) spectra, absorption and fluorescence spectra. In the pH 5 solution, citrate [(H2L)2-] self-assembles on the surface of positively-charged gold nanoparticle, which results in the [(Au)n(H2L)m]x- complex. In other words, one of carboxylate oxygens in (H2L)2- moves inward and combines with gold nanoparticle. The other carboxylate oxygens moves outward to form a supermolecular complex anion with x negative charges. Then by virtue of electrostatic attraction, hydrophobic force and charge transfer action, the complex anion binds with ST cation to form a new ion-association complex. Here (H2L)2- acts as a bridge. The formation of the complex results in the significant enhancement of RRS intensity, the appearance of new RRS spectrum, the red shift of plasma absorption band of gold nanoparticle as well as the decrease in the absorbance and fluorescence quenching for safranine T. In this work, the interaction between gold nanoparticle and ST on the RRS, absorption and fluorescence spectra has been investigated. The reason why RRS intensity increases greatly and the reaction mechanism have been inquired. The results show that RRS spectra can not only be used to study nanoparticle and reaction product, but also are a sensitive means to characterize and detect nanoparticles.
Yamaguchi, H; Wakabayashi, Y; Kubono, S; Hashimoto, T; Hayakawa, S; Kawabata, T; Iwasa, N; Teranishi, T; Kwon, Y K; Binh, D N; Khiem, L H; Duy, N N
2012-01-01
The resonance structure in $^{11}$C is particularly of interest with regard to the astrophysical $^{7}$Be($\\alpha$, $\\gamma$) reaction, relevant at high temperature, and to the $\\alpha$-cluster structure in $^{11}$C. The measurement was to determine unknown resonance parameters for the high excited states of $^{11}$C. In particular, the $\\alpha$ decay width can be useful information to discuss $\\alpha$ cluster structure in $^{11}$C. New measurements of the $^{7}$Be+$\\alpha$ resonant scattering and the $^{7}$Be($\\alpha$, $p$)$^{10}$B reaction in inverse kinematics were performed for center-of-mass energy up to 5.5 MeV, and the resonances at excitation energies of 8.9--12.7 MeV in the compound $^{11}$C nucleus were studied. Inelastic scattering of $^{7}$Be+$\\alpha$ and the $^{7}$Be($\\alpha$, $p_1$)$^{10}$B$^*$ reaction were also studied with a simultaneous $\\gamma$-ray measurement. The measurements were performed at the low-energy RI beam facility CRIB (CNS Radioactive Ion Beam separator) of the Center for Nucl...
Sub-Doppler resonances in the back-scattered light from random porous media infused with Rb vapor
Villalba, S; Lenci, L; Bloch, D; Lezama, A; Failache, H
2013-01-01
We report on the observation of sub-Doppler resonances on the back-scattered light from a random porous glass medium with rubidium vapor filling its interstices. The sub-Doppler spectral lines are the consequence of saturated absorption where the incident laser beam saturates the atomic medium and the back-scattered light probes it. Some specificities of the observed spectra reflect the transient atomic evolution under confinement inside the pores. Simplicity, robustness and potential miniaturization are appealing features of this system as a spectroscopic reference.
Enhancement of the nuclear forward glory effect in the {sup 11}Be + {sup 12}C system
Energy Technology Data Exchange (ETDEWEB)
Ostrowski, A.N.; Roussel-Chomaz, P.; Villari, A.C.C. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Lepine-Szily, A.; Lichtenthaeler Filho, R. [Sao Paulo Univ., SP (Brazil); Alamanos, N. [CEA Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee; Brandan, M.E. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico). Inst. de Fisica
1996-12-31
The possibility of obtaining information on peculiarities in the density distributions of light exotic nuclei from elastic scattering data by using the modified Generalized Optical Theorem for charged particles is studied. It is shown that model independent information on the forward nuclear scattering amplitude can be obtained. This quantity probes the outer part of the underlying scattering potential and is therefore sensitive to `halo-like` tails in the matter distribution. In the presence of such a tail a strong enhancement of the forward nuclear scattering amplitude at 0 deg is obtained. To demonstrate that this enhancement is even stronger that the one due to the well-established nuclear forward glory effect, synthetic data for the `non halo` {sup 10}Be+{sup 12}C and the `neutron-halo` {sup 11}Be+{sup 12}C systems are compared in the glory angular domain. (author). 17 refs.
Energy Technology Data Exchange (ETDEWEB)
Rosales M, P
2005-07-01
In this work we report the measurements carried out in the National Institute of Nuclear Research of Mexico (ININ) for the absolute section of fusion of the system {sup 12} C + {sup 12} C in an interval of energy of E{sub c.m.} 4.5-6.5 MeV with fine steps of 75 keV. The objective of measuring in fine steps is to register all the existent resonances. To be able to obtain an absolute normalization of the cross section, it was applied a method that allows to measure simultaneously the one number of projectiles that arrive to the target, as well as the numbers of nuclei in the target, even when this doesn't stay constant. In the chapter 2 the experimental procedure it is described, it is carried out with detail the analysis of the data and the results are shown. Later on the chapter 3 it is described with detail the method used for the absolute normalization, that is to say the form of obtaining the quantities N{sub p} and {eta}{sub T} of the equation is explained and the obtained results are presented. Additionally in the chapter 4 it was carried out a theoretical analysis applying models as that of barrier penetration and the optical model combined with the Breit-Wigner theory with the purpose of being able to reproduce the resonances of the excitation function. In the chapter 5 the concept of S-Astrophysicist factor it is introduced and this value is calculated for our data. Finally in the chapter 6 the conclusions of this work are presented. (Author)
Study and realization of heavy ion detectors. Application to the reaction 12C+24Mg
International Nuclear Information System (INIS)
The present study deals with elastic and inelastic scattering of 24 to 44 MeV center of mass 24Mg ions by 12C. The Strasbourg Q3D magnetic spectrograph has been used to measure the 1800 c.m. scattering cross-sections in detecting the corresponding recoiling ions at THETAsub(Lab) = 00. Statistical fluctuations are probably present. The 1,5 m long position sensitive focal plan hybride counter is described
Energy Technology Data Exchange (ETDEWEB)
Muñoz, Jorge A. [Intel Corporation, Information Technology Research, Hillsboro, OR 97124 (United States); Fultz, Brent [California Institute of Technology, Department of Applied Physics and Materials Science, Pasadena, CA 91125 (United States)
2015-07-23
Recent measurements of the phonon spectra of several Au-rich alloys of face-centered-cubic Fe-Au using inelastic neutron scattering and nuclear-resonant inelastic x-ray scattering are summarized. The Wills-Harrison model, accounting for charge transfer upon alloying, is used to explain the observed negative excess vibrational entropy of mixing, which increases the miscibility gap temperature in the system by an estimated maximum of 550 K and we adjudicate to a charge transfer from the Fe to the Au atoms that results in an increase in the electron density in the free-electron-like states and in stronger sd-hybridization. When Au is the solvent, this softens the Fe–Fe bonds but stiffens the Au–Au and Au–Fe bonds which results in a net stiffening relative to the elemental components.
Directory of Open Access Journals (Sweden)
J. P. Morgan
2012-06-01
Full Text Available We report X-ray resonant magnetic scattering studies of a Permalloy artificial square ice nanomagnet array, focussing on the field-driven evolution of the sum Σ and difference Δ signals of left and right handed circularly polarized synchrotron X-rays at different lateral positions in reciprocal space Qx. We used X-rays tuned to the Fe L3 resonance energy, with the scattering plane aligned along a principal symmetry axis of the array. Details of the specular Δ hysteresis curve are discussed, following the system magnetization from an initial demagnetized state. The periodic structure gives rise to distinct peaks at in-plane reciprocal Bragg positions, as shown by fitting Σ(Qx to a model based on a simple unit cell structure. Diffraction order-dependent hysteresis in Δ is observed, indicative of the reordering of magnetization on the system's two interpenetrating sublattices, which markedly deviates from an ideal Ising picture under strong applied fields.
Study of two- and multi-particle correlations in 12C+24Mg and 12C+208Pb reactions at E=35 AMeV
Directory of Open Access Journals (Sweden)
Quattrocchi L.
2016-01-01
Full Text Available Two and multi particle correlations from the decay of sources produced in 12C+24Mg and 12C+208Pb collisions at E=35 AMeV have been studied by using the forward part (1° < θlab < 30° of the CHIMERA multi-detector. Correlations and invariant mass spectroscopy are used to explore simultaneous and sequential decays of resonances in light isotopes with Z∼3-6, produced in peripheral collisions via the break-up of excited quasi-projectiles. Among them we mention 5Li, 6Li, 6Be, 8Be and the astrophysically important state in 12C decaying into three alpha particles. Results and future perspectives at the INFN-LNS will be presented.
Energy Technology Data Exchange (ETDEWEB)
Ghrayeb, Shadi Z. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mechanical and Nuclear Engineering; Ougouag, Abderrafi M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States); Ouisloumen, Mohamed [Westinghouse Electric Company, Cranberry Township, PA (United States); Ivanov, Kostadin N. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Mechanical and Nuclear Engineering
2014-01-01
A multi-group formulation for the exact neutron elastic scattering kernel is developed. It incorporates the neutron up-scattering effects, stemming from lattice atoms thermal motion and accounts for it within the resulting effective nuclear cross-section data. The effects pertain essentially to resonant scattering off of heavy nuclei. The formulation, implemented into a standalone code, produces effective nuclear scattering data that are then supplied directly into the DRAGON lattice physics code where the effects on Doppler Reactivity and neutron flux are demonstrated. The correct accounting for the crystal lattice effects influences the estimated values for the probability of neutron absorption and scattering, which in turn affect the estimation of core reactivity and burnup characteristics. The results show an increase in values of Doppler temperature feedback coefficients up to -10% for UOX and MOX LWR fuels compared to the corresponding values derived using the traditional asymptotic elastic scattering kernel. This paper also summarizes the results done on this topic to date.
Lin, F.
2015-01-01
The controversy about the glass transition on the nanoscale, e.g., the glass transition temperature (Tg ) of polymer thin films, is not fully resolved. The nanoscale dynamic behavior is strongly affected by the boundary conditions of the samples. Polymer thin films are ideal systems to study the dynamics of polymer chains under different confinements, which I varied in this thesis to gain more and better insight into this problem. rnrnResonance Enhanced Dynamic Light Scattering (REDLS) is a m...
Resonant Inelastic X-ray Scattering of Rare-Earth and Copper Systems
International Nuclear Information System (INIS)
Rare earths and copper systems were studied using X-ray absorption spectroscopy (XAS) and resonant inelastic X-ray scattering (RIXS). The use of monochromased synchotron radiation and improved energy resolution for RIXS made possible to obtain valuable information on the electronic structure in 4f, 5f and 3d systems. Experimental results for rare-earths (Ho, Gd, Cm, U, Np, Pu) were analyzed by atomic multiplet theory based on the Hartree-Fock calculations. The inelastic scattering structures in RIXS spectra at 5d edge of actinides found to be sensitive to actinide oxidation states in different systems. Comparison of experimental and calculated Cm 5d RIXS spectra gave direct information about valency of the 248-curium isotope in oxide. Scientific understanding of processes that control chemical changes of radioactive species from spent fuel is improved by studying interactions of actinide ions (U, Np, Pu) with corroded iron surfaces. RIXS measurements at the actinide 5d edge found to be sensitive to actinide oxidation states in different systems. Comparison of experimental and calculated Cm 5d RIXS spectra gave direct information about valency of the 248 curium isotope in oxide. Scientific understanding of processes that control chemical changes of radioactive species from spent fuel is improved by studying interactions of actinide ions (U, Np, Pu) with corroded iron surfaces. RIXS measurements at the actinide 5d edge indicate the reduction of U(VI), NP(V) and Pu(VI) to U(IV), Np(IV) and Pu(IV) by presence of iron ions. This thesis is also addressed to the study of changes in the electronic structure of copper films during interaction with synthetic groundwater solutions. The surface modifications induced by chemical reactions of oxidized 100 Angstrom Cu films with CL-, SO42- and HCO3- ions in aqueous solutions with various concentrations were studied in-situ using XAS. It was shown that the pH value, the concentration of Cl- ion and presence of HC3- ion in the
Zhou, Mingqiong; Peng, Jingdong; He, Rongxing; He, Yuting; Zhang, Jing; Li, Aiping
2015-02-01
A reliable and versatile high performance liquid chromatography coupled with resonance Rayleigh scattering method was established for the determination of three fluoroquinolones, including levofloxacin, norfloxacin and enrofloxacin in water sample and human urine sample. In pH 4.4-4.6 Britton-Robinson buffer medium, the fluoroquinolones separated by high performance liquid chromatography could react with erythrosine to form 1:1 ion-association complexes, which could make contributions to the great enhancement of RRS. The resonance Rayleigh scattering signal was recorded at λex = λem = 330 nm. The resonance Rayleigh scattering spectral characteristics of the drugs and the experimental conditions such as pH, detection wavelength, erythrosine concentration, flow rate, the length of reaction tube were studied. Quantum chemistry calculation, Fourier transform infrared spectroscopy and absorption spectroscopy were used to discuss the reaction mechanism. The recoveries of samples added standard ranged from 97.53% to 102.00%, and the relative standard deviation was below 4.64%. The limit of detection (S/N = 3) of 0.05-0.12 μg mL-1 was reached, and the linear regression coefficients were all above 0.999. The proposed method was proved as a simple, low cost and high sensitivity method.
Monreal, R Carmina; Apell, S Peter
2016-01-01
The detailed understanding of the physical parameters that determine Localized Surface Plasmon Resonances (LSPRs) is essential to develop new applications for plasmonics. A relatively new area of research has been opened by the identification of LSPRs in low carrier density systems obtained by doping semiconductor quantum dots. We investigate theoretically how diffuse surface scattering of electrons in combination with the effect of quantization due to size (QSE) impact the evolution of the LSPRs with the size of these nanosystems. Two key parameters are the length $R_0$ giving the strength of the QSE and the velocity $\\beta_T$ of the electronic excitations entering in the length scale for diffuse surface scattering. While the QSE itself only produces a blueshift in energy of the LSPRs, the diffuse surface scattering mechanism gives to both energy and linewidth an oscillatory-damped behavior as a function of size, with characteristic lengths that depend on material parameters. Thus, the evolution of the LSPRs...
Burova, T. G.; Shcherbakov, R. S.
2016-05-01
Quantum-mechanical calculations of the intensity distribution in the resonant Raman scattering spectra of aqueous solutions of tyrosine excited by laser radiation with wavelengths of 244, 229, 218, 200, and 193 nm, as well as in the nonresonant Raman scattering spectrum excited at a wavelength of 488 nm, are performed. Satisfactory agreement is achieved between the calculation results and the experimental data. It is shown that the changes in the intensity distribution observed in the spectra with a change in the excitation wavelength from 244 to 193 nm correlate with the determined changes in the contribution made by excited electronic states into the scattering tensor components. It is noted that it is necessary to take into account the Herzberg-Teller effect and that the number of excited electronic states taken into account considerably affects the calculated relative intensities of lines. The possibility of existence of several tyrosine conformers in aqueous solution at room temperature is shown.
International Nuclear Information System (INIS)
The angular dependence of the tensor Ayy and vector Ay analyzing powers in the inelastic scattering of deuterons with a momentum of 9.0 GeV/c on hydrogen and carbon has been measured. The range of measurements corresponds to the baryonic resonance excitation with masses of ∼2.2-2.6 GeV/c2. The Ayy data, being in good agreement with the previous results, demonstrate an approximate t scaling up to -1.5 (GeV/c)2. The large values of Ay show a significant role of the spin-dependent part of the elementary amplitude of the NN → NN* reaction. The results of the experiment are compared with model predictions of the plane-wave impulse approximation
PREFACE: REXS 2013 - Workshop on Resonant Elastic X-ray Scattering in Condensed Matter
Beutier, G.; Mazzoli, C.; Yakhou, F.; Brown, S. D.; Bombardi, A.; Collins, S. P.
2014-05-01
The aim of this workshop was to bring together experts in experimental and theoretical aspects of resonant elastic x-ray scattering, along with researchers who are new to the field, to discuss important recent results and the fundamentals of the technique. The meeting was a great success, with the first day dedicated to students and new researchers in the field, who received introductory lectures and tutorials. All conference delegates were invited either to make an oral presentation or to present a poster, accompanied by a short talk. The first two papers selected for the REXS13 proceedings (Grenier & Joly and Helliwell) give a basic background to the theory of REXS and applications across a wide range of scientific areas. The remainder of the papers report on some of the latest scientific results obtained by applying the REXS technique to contemporary problems in condensed matter, materials and x-ray physics. It is hoped that these proceedings provide a snapshot of the current status of a vibrant and diverse scientific technique that will be of value not just to those who attended the workshop but also to any other reader with an interest in the subject. Local Scientific Committee REXS13 International Scientific Advisory Committee M Altarelli, European XFEL, Germany F de Bergevin, European Synchrotron Radiation Facility, France J Garcia-Ruiz, Universidad de Zaragoza, Spain A I Goldman, Iowa State University, USA M Goldmann, Institut Nanosciences, France T Schulli, European Synchrotron Radiation Facility, France C R Natoli, Laboratori Nazionali de Frascati, Italy G Materlik, Diamond Light Source, UK L Paolasini, European Synchrotron Radiation Facility, France U Staub, Paul Scherrer Institut, Switzerland K Finkelstein, Cornell University, USA Y Murakami, Photon Factory, Japan REXS13 Local Scientific Committee G Beutier, CNRS Grenoble, France C Mazzoli, Politecnico di Milano, Italy F Yakhou, European Synchrotron Radiation Facility, France S D Brown, XMaS UK CRG
Energy Technology Data Exchange (ETDEWEB)
Leutenegger, M.A.; /Columbia U.; Owocki, S.P.; /Bartol Research Inst.; Kahn, S.M.; /KIPAC, Menlo Park; Paerels, F.B.S.; /Columbia U.
2006-10-10
We fit the Doppler profiles of the He-like triplet complexes of O VII and N VI in the X-ray spectrum of the O star {zeta} Pup, using XMM-Newton RGS data collected over {approx} 400 ks of exposure. We find that they cannot be well fit if the resonance and intercombination lines are constrained to have the same profile shape. However, a significantly better fit is achieved with a model incorporating the effects of resonance scattering, which causes the resonance line to become more symmetric than the intercombination line for a given characteristic continuum optical depth {tau}{sub *}. We discuss the plausibility of this hypothesis, as well as its significance for our understanding of Doppler profiles of X-ray emission lines in O stars.
Institute of Scientific and Technical Information of China (English)
He Ping; Li Si-Ning; Fan Rong-Wei; Li Xiao-Hui; Xia Yuan-Qin; Yu Xin; Chen De-Ying
2012-01-01
Femtosecond time-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy is used to investigate gaseous molecular dynamics.Due to the spectrally broad laser pulses,usually poorly resolved spectra result from this broad spectroscopy.However,it can be demonstrated that by the electronic resonance enhancement optimization control a selective excitation of specific vibrational mode is possible.Using an electronically resonance-enhanced effect,iodine molecule specific CARS spectroscopy can be obtained from a mixture of iodine-air at room temperature and a pressure of 1 atm (corresponding to a saturation iodine vapour as low as about 35 Pa).The dynamics on either the electronically excited state or the ground state of iodine molecules obtained is consistent with previous studies (vacuum,heated and pure iodine) in the femtosecond time resolved CARS spectroscopy,showing that an effective method of suppressing the non-resonant CARS background and other interferences is demonstrated.
International Nuclear Information System (INIS)
In the present work the phenomenon of fine structure in the region of the isoscalar giant quadrupole resonance in a number of heavy and medium-heavy nuclei is systematically investigated for the first time. High energy-resolution inelastic proton scattering experiments were carried out in September-October 2001 and in October 2003 at the iThemba LABS cyclotron facility in South Africa with an incident proton energy of 200 MeV. The obtained data with the energy resolution of triangle E58Ni,89Y,90Zr,120Sn,142Nd,166Er,208Pb), thereby establishing the global character of this phenomenon. Fine structure can be described using characteristic energy scales, appearing as a result of the decay of collective modes towards the compound nucleus through a hierarchy of couplings to complex degrees of freedom. For the extraction of the characteristic energy scales from the spectra an entropy index method and a novel technique based on the wavelet analysis are utilized. The global analysis of available data shows the presence of three groups of scales, according to their values. To the first group belong the scales with the values around and below 100 keV, which were detected in all the nuclei studied. The second group contains intermediate scales in the range of 100 keV to 1 MeV. These scales show large variations depending on the nuclear structure of the nucleus. The largest scales above 1 MeV are classified to the third group, describing the global structure of the resonance (the width). The interpretation of the observed scales is realized via the comparison with microscopic model calculations including the coupling of the initial one-particle-one-hole excitations to more complex configurations. A qualitative agreement of the experimentally observed scales with those obtained from the theoretical predictions supports the suggestion of the origin of fine structure from the coupling to the two-particle-two-hole states. However, quantitatively, large deviations are observed for
Measurement of the ^12C+^12C Fusion Reaction with MUSIC
Carnelli, P. F. F.; Almaraz-Calderon, S.; Henderson, D.; Rehm, K. E.; Albers, M.; Alcorta, M.; Bertone, P. F.; Esbensen, H.; Fernandez-Niello, J. O.; Jiang, C. L.; Lighthall, J. C.; Marley, S. T.; Palchan-Hazan, T.; Pardo, R. C.; Paul, M.
2012-10-01
The fusion of the ^12C+^12C system is of great interest in nuclear structure and nuclear astrophysics. Above the Coulomb barrier, the excitation function of this system exhibits oscillations, which are not well understood. There is also a significant discrepancy between the experimental fusion cross-section and recent coupled-channel calculations that is not present in other carbon systems. To address these issues, we have re-measured the fusion excitation function for ^12,13C+^12C in the energy range of 10 MeV MUSIC) detector. The gas of the ionization chamber (CH4) served as both the target material and the counter gas. One of the main advantages of this method is that the excitation function is measured over a large range of energies using only one beam energy. This method has been proven to be successful and it will be used to measure fusion reactions in other light systems. The experimental results will be presented and compared to previous experimental data and theoretical models.
Chang, Shanshan; Zhu, Zhengping; Ni, Binbin; Cao, Xing; Luo, Weihua
2016-10-01
Several extremely low-frequency (ELF)/very low-frequency (VLF) wave generation experiments have been performed successfully at High-Frequency Active Auroral Research Program (HAARP) heating facility and the artificial ELF/VLF signals can leak into the outer radiation belt and contribute to resonant interactions with energetic electrons. Based on the artificial wave properties revealed by many of in situ observations, we implement test particle simulations to evaluate the effects of energetic electron resonant scattering driven by the HAARP-induced ELF/VLF waves. The results indicate that for both single-frequency/monotonic wave and multi-frequency/broadband waves, the behavior of each electron is stochastic while the averaged diffusion effect exhibits temporal linearity in the wave-particle interaction process. The computed local diffusion coefficients show that, the local pitch-angle scattering due to HARRP-induced single-frequency ELF/VLF whistlers with an amplitude of ∼10 pT can be intense near the loss cone with a rate of ∼10-2 rad2 s-1, suggesting the feasibility of HAARP-induced ELF/VLF waves for removal of outer radiation belt energetic electrons. In contrast, the energy diffusion of energetic electrons is relatively weak, which confirms that pitch-angle scattering by artificial ELF/VLF waves can dominantly lead to the precipitation of energetic electrons. Moreover, diffusion rates of the discrete, broadband waves, with the same amplitude of each discrete frequency as the monotonic waves, can be much larger, which suggests that it is feasible to trigger a reasonable broadband wave instead of the monotonic wave to achieve better performance of controlled precipitation of energetic electrons. Moreover, our test particle scattering simulation show good agreement with the predictions of the quasi-linear theory, confirming that both methods are applied to evaluate the effects of resonant interactions between radiation belt electrons and artificially generated
Institute of Scientific and Technical Information of China (English)
2007-01-01
In pH 4.5 Britton-Robinson(BR)buffer solution,erythrosin(ET)can react with diphenhydramine(DP)to form a 1:1 ion-association complex,which not only results in the change of the absorption spectra,but also results in the great enhancement of resonance Rayleigh scattering(RRS)and the quenching of fluorescence.Furthermore,a new RRS spectrum will appear,and the maximum RRS wavelength was located at about 580 nm.In this work,the spectral characteristics of the absorption,fluorescence and RRS,the optimum conditions of the reaction and the properties of an analytical chemistry were inves- tigated.A sensitive,simple and new method for the determination of DP by using erythrosin as a probe has been developed.The detection limits for DP were 0.0020μg/mL for RRS method,0.088μg/mL for absorption method and 0.094μg/mL for fluorophotometry.There was a linear relationship between the absorbance,RRS and fluorescence intensities and the drug concentration in the range of 0.0067-2.0, 0.29-6.4 and 0.31-3.2μg/mL,respectively.The effects of the interaction of diphenhydramine and erythrosin on the absorption,fluorescence and resonance Rayleigh scattering spectra were discussed. In light polarization experiment,the polarization of RRS at maximum wavelength was measured to be P =0.9779,and it revealed that the RRS spectrum of DP-ET complex consists mostly of resonance scat- tering and few resonance fluorescence.In this study,enthalpy of formation and mean polarizability were calculated by AM1 quantum chemistry method.In addition,the reaction mechanism and the rea- sons for the enhancement of scattering spectra and the energy transfer between absorption,fluores- cence and RRS were discussed.
Resonant X-ray scattering and multipolar order in actinide dioxides
International Nuclear Information System (INIS)
Full text of publication follows: The discovery in 2002 of electric quadrupole ordering in the NpO2 opened a new chapter in the understanding of the low-temperature ground states of actinide dioxides, insulating compounds with the simple cubic CaF2 crystal structure and general formula U1-xNpxO2 (0 ≤ x ≤ 1). The phenomenon found at 25 K in NpO2 is that the 5f charge distribution develops an anisotropic component, with long-range ordering of the charge quadrupoles driven by a primary magnetic octupolar order parameter belonging to the totally symmetric irreducible representation of L = 3 in D3d symmetry (□1). The experiments consist of tuning the photon energy to the actinide M absorption edge (at which photon energy core 3d electrons are promoted to the partially occupied 5f valence states), and then, once the repeat of the anisotropic charge distribution is known, to measure the azimuthal distribution of the scattered resonant x-ray intensity. This intensity distribution is related to the symmetry of the 5f anisotropic charge distribution. The experiments were performed at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, with the single crystals mounted in ITU. NpO2 shows no measurable magnetic dipole component. In 2003 experiments were performed on a single crystal with x = 0.25. Dipole ordering was found on both the U and Np ions, and quadrupolar ordering was also found associated with both ions. However, these were different from those in pure NpO2. Whereas a longitudinal (L) 3-k configuration was found for NpO2, the x = 0.25 sample was found to have a transverse (T) 3-k configuration. The understanding of these different configurations then allowed an experiment to be performed in 2005 on a single crystal of UO2. The azimuthal dependence of the intensity from non-specular reflections reveals 3-k T anti-ferro-electric-quadrupolar order also UO2. The complication in UO2 is that both dipole ordering and an internal distortion of the
Low energy excitations in iridates studied with Resonant Inelastic X-ray Scattering
Liu, Xuerong
2013-03-01
In the iridium oxides, the strong spin-orbit coupling (SOC) of the 5d iridium electrons entangles the orbital and spin degrees of freedom, providing opportunities for exotic magnetic states with highly anisotropic exchange interactions. At the same time, the spatially extended 5d electrons are expected to have much stronger hybridization with the oxygen 2p orbitals, comparing with that in 3d transition element compounds. Both factors make crystal symmetry and local environment crucial in determining the electronic and magnetic properties of the iridates. We present here our resonant inelastic X-ray scattering (RIXS) studies of a number of octahedrally coordinated iridates with special structures, exploring these effects. In particular, for the 1-D spin 1/2 chain compound, Sr3CuIrO6, the wavefunction of the hole in the t2g manifold was reconstructed based on the RIXS spectra. Our results show that it is significantly modified from the isotropic shape expected for Jeff = 1 / 2 states in the strong SOC limit, due to the distortion of the oxygen octahedral cage. This distortion is comparable to, or smaller than, that present in most iridates and thus this work emphasizes the importance of local symmetry for the iridate families. Further, the magnetic excitations of this material were also measured. A large gap of ~30 meV, was found, comparable to the magnetic dispersion bandwidth. This is in contrast to the gapless dispersion expected for linear chain with isotropic Heisenberg exchange interaction. We also studied Na4Ir3O8 which has a hyperkagome lattice, and is a candidate quantum spin liquid. Here, a low energy continuum is observed below the d-d excitations. Optical conductivity measurements performed on the same sample and polarization dependence of the RIXS signal suggest that these excitations are magnetic in origin, agreeing with the spin-liquid state prediction. The work at Brookhaven was supported by the U.S. Department of Energy, Division of Materials Science
International Nuclear Information System (INIS)
Highlights: •The high specificity of RIXS ideally suits time-resolved measurements. •Methods relating to the core hole lifetime cover the low femtosecond regime. •Pump-probe methods are used starting at sub-ps time scales. •FELs and synchrotrons are useful for pump-probe studies. •Examples from solid state dynamics and molecules are discussed. -- Abstract: Dynamics in materials typically involve different degrees of freedom, like charge, lattice, orbital and spin in a complex interplay. Time-resolved resonant inelastic X-ray scattering (RIXS) as a highly selective tool can provide unique insight and follow the details of dynamical processes while resolving symmetries, chemical and charge states, momenta, spin configurations, etc. In this paper, we review examples where the intrinsic scattering duration time is used to study femtosecond phenomena. Free-electron lasers access timescales starting in the sub-ps range through pump-probe methods and synchrotrons study the time scales longer than tens of ps. In these examples, time-resolved resonant inelastic X-ray scattering is applied to solids as well as molecular systems
Wang, Jian; Liu, Zhongfang; Liu, Jiangtao; Liu, Shaopu; Shen, Wei
2008-03-01
In pH 4.4-4.5 Britton-Robinson (BR) buffer solution, fluoroquinolone antibiotics (FLQs) including ciprofloxacin (CIP), norfloxacin (NOR), levofloxacin (LEV) and lomefloxacin (LOM) could react with erythrosine (Ery) to form 1:1 ion-association complexes, which not only resulted in the changes of the absorption spectra and the quenching of fluorescence, but also resulted in the great enhancement of resonance Rayleigh scattering (RRS). These offered some indications of the determination of fluoroquinolone antibiotics by spectrophotometric, fluorescence and resonance Rayleigh scattering methods. The detection limits for fluoroquinolone antibiotics were in the range of 0.097-0.265 μg/mL for absorption methods, 0.022-0.100 μg/mL for fluorophotometry and 0.014-0.027 μg/mL for RRS method, respectively. Among them, the RRS method had the highest sensitivity. In this work, the spectral characteristics of the absorption, fluorescence and RRS, the optimum conditions of the reactions and the properties of the analytical chemistry were investigated. The methods have been successfully applied to determination of some fluoroquinolone antibiotics in human urine samples and tablets. Taking CIP-Ery system as an example, the charge distribution, the enthalpy of formation and the mean polarizability were calculated by density function theory (DFT) method. In addition, the reasons for the enhancement of scattering spectra were discussed.
Analysis of Order Formation in Block Copolymer Thin Films UsingResonant Soft X-Ray Scattering
Energy Technology Data Exchange (ETDEWEB)
Virgili, Justin M.; Tao, Yuefei; Kortright, Jeffrey B.; Balsara,Nitash P.; Segalman, Rachel A.
2006-11-27
The lateral order of poly(styrene-block-isoprene) copolymer(PS-b-PI) thin films is characterized by the emerging technique ofresonant soft X-ray scattering (RSOXS) at the carbon K edge and comparedto ordering in bulk samples of the same materials measured usingconventional small-angle X-ray scattering. We show resonance using theoryand experiment that the loss of scattering intensity expected with adecrease in sample volume in the case of thin films can be overcome bytuning X-rays to the pi* resonance of PS or PI. Using RSOXS, we study themicrophase ordering of cylinder- and phere-forming PS-b-PI thin films andcompare these results to position space data obtained by atomic forcemicroscopy. Our ability to examine large sample areas (~;9000 mu m2) byRSOXS enables unambiguous identification of the lateral lattice structurein the thin films. In the case of the sphere-forming copolymer thin film,where the spheres are hexagonally arranged, the average sphere-to-spherespacing is between the bulk (body-centered cubic) nearest neighbor andbulk unit cell spacings. In the case of the cylinder-forming copolymerthin film, the cylinder-to-cylinder spacing is within experimental errorof that obtained in the bulk.
{sup 12}C(0{sub 2}{sup +})+α molecular states in a microscopic four α model
Energy Technology Data Exchange (ETDEWEB)
Dufour, M., E-mail: mdufour@iphc.cnrs.fr [IPHC Bat27, IN2P3–CNRS/Université Louis Pasteur BP28, F-67037 Strasbourg Cedex 2 (France); Descouvemont, P., E-mail: pdesc@ulb.ac.be [Physique Nucléaire Théorique et Physique Mathématique, C.P. 229, Université Libre de Bruxelles (ULB), B 1050 Brussels (Belgium)
2014-07-15
The {sup 16}O nucleus is investigated within a {sup 12}C+α four α multicluster model. The generator coordinate method combined with the microscopic R-matrix method is used to determine bound and resonant states. The {sup 12}C nucleus is described by 3 α clusters located at the apexes of isosceles triangles. We optimize the generator coordinates to get a reasonable description of the 0{sub 2}{sup +}–0{sub 1}{sup +} energy gap, where the 0{sub 2}{sup +} is the so-called Hoyle state, considered as a 3 α state. Our calculations mainly focus on resonances located near the {sup 12}C(0{sub 2}{sup +})+α threshold. We emphasize the difficulty to interpret broad resonant states and we show that bound state approximation methods are not well adapted in the context of our study. An R-matrix analysis suggests the existence of 0{sup +}, 2{sup +} and 4{sup +} molecular states which present a significant {sup 12}C(0{sub 2}{sup +})+α structure, and which may form a rotational band.
Soman, M. R.; Hall, D. J. (David John); Tutt, J. H.; Murray, N. J.; Holland, A. D.; Schmitt, T.; Raabe, J.; Schmitt, B.
2011-01-01
The Super Advanced X-ray Emission Spectrometer (SAXES) at the Advanced Resonant Scattering (ADRESS) beamline of the Swiss Light Source is a high-resolution X-ray spectrometer used as an end station for Resonant Inelastic X-ray Scattering from 400 eV to 1600 eV. Through the dispersion of photons across a CCD, the energy of scattered photons may be determined by their detected spatial position. The limiting factor of the energy resolution is currently the spatial resolution achieved with the CC...
Tribelsky, M I
2015-01-01
A detailed analytical inspection of light scattering by a particle with high refractive index m+i\\kappa and small dissipative constant \\kappa is presented. We have shown that there is a dramatic difference in the behavior of the electromagnetic field within the particle (inner problem) and the scattered field outside it (outer problem). With an increase in m at fix values of the other parameters, the field within the particle asymptotically converges to a periodic function of m. The electric and magnetic type Mie resonances of different orders overlap substantially. It may lead to a giant concentration of the electromagnetic energy within the particle. At the same time, we demonstrate that identical transformations of the solution for the outer problem allow to present each partial scattered wave as a sum of two partitions. One of them corresponds to the m-independent wave, scattered by a perfectly reflecting particle and plays the role of a background, while the other is associated with the excitation of a s...
Thermal properties of light nuclei from 12C + 12C fusion-evaporation reactions
Morelli, L.; Baiocco, G.; D'Agostino, M.; Gulminelli, F.; Bruno, M.; Abbondanno, U.; Appannababu, S.; Barlini, S.; Bini, M.; Casini, G.; Cinausero, M.; Degerlier, M.; Fabris, D.; Gelli, N.; Gramegna, F.; Kravchuk, V. L.; Marchi, T.; Olmi, A.; Pasquali, G.; Piantelli, S.; Valdré, S.; Raduta, Ad R.
2014-07-01
The 12C + 12C reaction at 95 MeV has been studied through the complete charge identification of its products by means of the GARFIELD+RCo experimental set-up at INFN Laboratori Nazionali di Legnaro (LNL). In this paper, the first of a series of two, a comparison to a dedicated Hauser-Feshbach calculation allows selecting a set of dissipative events which corresponds, to a large extent, to the statistical evaporation of highly excited 24Mg. Information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain is also extracted. The set of data puts strong constraints on the behaviour of the level density (LD) of light nuclei above the threshold for particle emission. In particular, a fast increase of the LD parameter with excitation energy is supported by the data. Residual deviations from a statistical behaviour are seen in two specific channels, and tentatively associated with a contamination from direct reactions and/or α-clustering effects. These channels are studied in further details in the second paper of the series.
Thermal properties of light nuclei from $^{12}$C+$^{12}$C fusion-evaporation reactions
Morelli, L; D'Agostino, M; Gulminelli, F; Bruno, M; Abbondanno, U; Appannababu, S; Barlini, S; Bini, M; Casini, G; Cinausero, M; Degerlier, M; Fabris, D; Gelli, N; Gramegna, F; Kravchuk, V L; Marchi, T; Pasquali, G; Piantelli, S; Valdré, S; Raduta, Ad R
2014-01-01
The $^{12}$C+$^{12}$C reaction at 95 MeV has been studied through the complete charge identification of its products by means of the GARFIELD+RCo experimental set-up at INFN Laboratori Nazionali di Legnaro (LNL). In this paper, the first of a series of two, a comparison to a dedicated Hauser-Feshbach calculation allows to select a set of dissipative events which corresponds, to a large extent, to the statistical evaporation of highly excited $^{24}$Mg. Information on the isotopic distribution of the evaporation residues in coincidence with their complete evaporation chain is also extracted. The set of data puts strong constraints on the behaviour of the level density of light nuclei above the threshold for particle emission. In particular, a fast increase of the level density parameter with excitation energy is supported by the data. Residual deviations from a statistical behaviour are seen in two specific channels, and tentatively associated with a contamination from direct reactions and/or $\\alpha$-clusteri...
Interplay between structure and magnetism in HoxPr1-x alloys. 2. Resonant x-ray magnetic scattering
DEFF Research Database (Denmark)
Vigliante, A.; Christensen, M.J.; Hill, J.P.;
1998-01-01
X-ray-scattering techniques have been used to study the crystal and magnetic structures of HoxPr1-x alloys in the form of thin films. Three distinct crystal structures are found as a function of concentration x, each of which has a characteristic magnetic structure. For x greater than or equal to 0.......6 a hexagonal-close-packed phase is found with the magnetic moments ordered in a basal-plane helix, whereas for 0.4 less than or equal to x... hexagonal-close-packed and remain nonmagnetic down to the lowest temperatures studied. Using x-ray magnetic resonance scattering techniques, we demonstrate that a small, static spin-density wave is induced within the alloy 5d band at both the Pr and Ho sites in both of the magnetically ordered phases...
Ye, Lingling; Wen, Guiqing; Ouyang, Huixiang; Liu, Qingye; Liang, Aihui; Jiang, Zhiliang
2016-04-01
Gold nanoparticles (AuNP) have catalysis on the reaction of HAuCl4-H2O2. The produced AuNP have strong resonance Rayleigh scattering (RRS) effect and surface-enhanced resonance Raman scattering (SERS) effect when Victoria blue B (VBB) and rhodamine S (RhS) were used as probes. The increased RRS/SERS intensity respond linearly with the concentration of gold nanoparticles (AuNPB) which synthesized by NaBH4 over 0.038–76 ng/mL, 19–285 ng/mL, 3.8–456 ng/mL respectively. Four kinds of tested nanoparticles have catalysis on the HAuCl4-H2O2 particles reaction. Thus, a novel nanocatalysis surface plasmon resonance-scattering (SPR-S) analytical platform was developed for AuNP. The DNAzyme strand hybridized with the substrate strand to form double-stranded DNA (dsDNA) which couldn’t protect AuNPc to aggregate to AuNPc aggregations, having strong RRS effect. Upon addition of Pb2+, dsDNA could be cracked by Pb2+ to produce single-stranded DNA (ssDNA) that adsorbed on the AuNPc surface to form AuNPc-ssDNA conjugates. The conjugates have strong catalysis on HAuCl4-H2O2 reaction. With increased Pb2+ concentration, the concentration of AuNPc-ssDNA increased and lead to the catalytic activity stronger. The increased RRS intensity responds linearly with Pb2+ concentration over 16.7–666.7 nmol/L. The SERS intensity responded linearly with the concentration of Pb2+ over 50–500 nmol/L.
A setup for resonant inelastic soft x-ray scattering on liquids at free electron laser light sources
International Nuclear Information System (INIS)
We present a flexible and compact experimental setup that combines an in vacuum liquid jet with an x-ray emission spectrometer to enable static and femtosecond time-resolved resonant inelastic soft x-ray scattering (RIXS) measurements from liquids at free electron laser (FEL) light sources. We demonstrate the feasibility of this type of experiments with the measurements performed at the Linac Coherent Light Source FEL facility. At the FEL we observed changes in the RIXS spectra at high peak fluences which currently sets a limit to maximum attainable count rate at FELs. The setup presented here opens up new possibilities to study the structure and dynamics in liquids.
Skipetrov, S E
2016-01-01
We use the random Green's matrix model to study the scaling properties of the localization transition for scalar waves in a three-dimensional (3D) ensemble of resonant point scatterers. We show that the probability density $p(g)$ of normalized decay rates of quasi-modes $g$ is very broad at the transition and in the localized regime and that it does not obey a single-parameter scaling law. The latter holds, however, for the small-$g$ part of $p(g)$ which we exploit to estimate the critical exponent $\
Institute of Scientific and Technical Information of China (English)
Qin WEI; Dan WU; Yan LI; Jun Hong WANG; Yan LIU; Bin DU
2005-01-01
Based on the enhancement of resonance light scattering (RLS) of m-nitrophenylfluorone-Mo(Ⅵ) complex by protein, a novel method for protein microdetermination in Tween 20microemulsion has been developed. Under optimum condition, the linear ranges of bovine serum albumin are 0 ～ 0.03 μg.mL-1 with detection limits of 3.10 ng.mL-1. Most of amino acids and metal ions do not interfere. The method can be applied to determination of residual protein in penicillin Na salt and penicillin G potassium salt samples with satisfactory results.
Mu-Tian, Cheng; Wei-Wei, Zong; Gen-Long, Ye; Xiao-San, Ma; Jia-Yan, Zhang; Bing, Wang
2016-06-01
We investigate theoretically single photon transport properties in coupled-resonator waveguide coupling with a nanocavity interacting with an external mirror. By using the discrete coordinates approach, transmission and reflection amplitudes of the propagating single photon in the waveguide are obtained. The influence of the coupling strength between the nanocavity and the external mirror on the single photon scattering spectra is discussed. We also extend the results to the waveguide with linear and quadratic form dispersion relations. Supported by the National Natural Science Foundation of China under Grant Nos. 11105001 and 61472282, the Anhui Provincial Natural Science Foundation under Grant Nos. 1408085QA22, 1608085MA09, and 1508085MF129.
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
In this study,based on its enhancement effect on resonance light scattering (RLS) of fluorosurfactant (FSN)-capped gold nanoparticles (GNPs),we reported a simple approach for the rapid sensing of captopril. Under optimum conditions,the lowest detectable concentration of captopril through this approach (S/N=3) was 0.01μg/mL. The calibration curve was linear over the range of 0.08-4.0μg/mL for the detection of captopril. The recoveries of captopril were found to fall in the range between 99% and 100%. We have...
Resonant inelastic soft x-ray scattering of CdS: a two-dimensional electronic structure map approach
Weinhardt, L.
2010-01-01
Resonant inelastic x-ray scattering (RIXS) with soft x-rays is uniquely suited to study the elec-tronic structure of a variety of materials, but is currently limited by low (fluorescence yield) count rates. This limitation is overcome with a new high-transmission spectrometer that allows to measure soft x-ray RIXS "maps." The S L2,3 RIXS map of CdS is discussed and compared with density functional calculations. The map allows the extraction of decay channel-specific "absorp-tion spectra," giv...
Benjamin, David; Klich, Israel; Demler, Eugene
2014-06-20
We show that a simple model of noninteracting quasiparticles accurately describes resonant inelastic x-ray scattering (RIXS) experiments in the hole-doped cuprate superconductors. Band structure alone yields signatures previously attributed to collective magnetic modes, such as the dispersing peaks and nontrivial polarization dependence found in several experiments. We conclude that RIXS data can be explained without positing the existence of magnetic excitations that persist with increasing doping. In so doing we develop a formalism for RIXS in itinerant electron systems that accounts for the positively charged core hole exactly and discover a mechanism by which the core hole produces polarization dependence mimicking that of a magnetic system. PMID:24996103
Laporta, V; Tennyson, J
2016-01-01
Resonant vibrational-excitation cross sections and rate constants for electron scattering by molecular oxygen are presented. Transitions between all 42 vibrational levels of O$_2(\\textrm{X}\\ ^3\\Sigma_g^- $) are considered. Molecular rotations are parameterized by the rotational quantum number $J$ which is considered in the range 1 to 151. The lowest four resonant states of O$_2^-$, $^2\\Pi_g$, $^2\\Pi_u$, $^4\\Sigma_u^-$ and $^2\\Sigma_u^-$, are taken into account. The calculations are performed using the fixed-nuclei R-matrix approach to determine the resonance positions and widths, and the boomerang model to characterize the nuclei motion. Two energy regions below and above 4~eV are investigated: the first one is characterized by sharp structures in the cross section, and the second by a broad resonance peaked at 10~eV. The computed cross sections are compared with theoretical and experimental results available in literature for both the energy regions, and are made available for use by modelers. The effect of ...
ELECTRONIC STRUCTURE OF CLUSTER ASSEMBLED Al12C (Si) SOLID
Institute of Scientific and Technical Information of China (English)
QUAN HONG-JUN; GONG XIN-GAO
2000-01-01
The electronic structures of the cluster-assembled solid Al12C (Si) are studied by the ab initio method. We find that Al12C (Si) can solidify into a van der Waals solid. The electronic band structures show very weak dispersion. The main features in the electronic structure of cluster are retained in the solid, and an energy gap up to about 1.5 eV is observed for Al12C and Al12Si solids.
Indian Academy of Sciences (India)
B J Roy; A Parmar; T Nandi; Biraja Mohanty; M Oswal; Sunil Kumar; A Jhingan; V Jha; D C Biswas
2016-01-01
Cross-sections for one- and multinucleon transfer reactions, namely, 58Ni(12C, 13C), 58Ni(12C, 11C), 58Ni(12C, 11B), 58Ni(12C, 10B), 58Ni(12C, 10Be), 58Ni(12C, 9Be), 58Ni(12C, 8Be.s.), 58Ni(12C, 7Be), 58Ni(12C, 7Li) and 58Ni(12C, 6Li) have been measured at an incident energy of 60 MeV. The reaction cross-section for the corresponding transfer channels in the system 12C+56Fe have also been measured under the same kinematical conditions. Angular distribution of the elastic scattering cross-section is measured at 60 MeV. The measured elastic scattering angular distributions for these two systems have been analysed using the optical model search code SFRESCO and the potential parameters are extracted. The multinucleon transfer data are analysed to obtain cross-section dependence on the number of nucleons transferred and on the ground state -values. The transfer probabilities for multinucleon stripping are extracted. A detailed comparison in the multiparticle stripping and elastic scattering cross-sections between these two systems are made to understand the mechanism of multinucleon transfer and possible role of two extra protons in 58Ni target nucleus as compared to the 56Fe core.
On the inner Double-Resonance Raman scattering process in bilayer graphene
Mafra, D. L.; Moujaes, E. A.; Nunes, R. W.; Pimenta, M. A.
2010-01-01
The dispersion of phonons and the electronic structure of graphene systems can be obtained experimentally from the double-resonance (DR) Raman features by varying the excitation laser energy. In a previous resonance Raman investigation of graphene, the electronic structure was analyzed in the framework of the Slonczewski-Weiss-McClure (SWM) model, considering the outer DR process. In this work we analyze the data considering the inner DR process, and obtain SWM parameters that are in better a...
Yang, Bin; Lv, Sifang; Chen, Feng; Liu, Chan; Cai, Changqun; Chen, Chunyan; Chen, Xiaoming
2016-03-17
A novel resonance light scattering sensor based on the molecularly imprinted polymers (MIPs) technique was developed for specific recognition of the trace quantities of papain (Pap). In this sensor, as the specific recognition element, an excellent biocompatibility of protein-imprinted polymer without fluorescent materials was easily prepared, which based on the effective synthesis of mussel-inspired bionic polydopamine (PDA) on the surface of SiO2 nanoparticles (SiO2@PDA NPs). This recognition element could capture the target protein selectively, which led to the enhancement of resonance light scattering intensity with the increasing of the target protein concentration. The sensor was applied to determine Pap in the linear concentration range of 2.0-20.0 nM with a correlation coefficient r = 0.9966, and a low detection limit of 0.63 nM. The relative standard deviation for 14 nM of Pap was 1.02% (n = 7). In addition, the specificity study confirmed the resultant Pap-imprinted SiO2@PDA NPs had a high-selectivity to Pap, and the practical analytical performance was further examined by evaluating the detection of Pap in the dietary supplement with satisfactory results, with good recoveries of 97.5-105.3%. PMID:26920781
The phi(1020) a0(980) S-wave scattering and hints for a new vector-isovector resonance
Alvarez-Ruso, L; Alarcon, J M
2010-01-01
We have studied the phi(1020)a0(980) S-wave scattering at threshold energies employing chiral Lagrangians coupled to vector mesons by minimal coupling. The interaction is described without new free parameters by considering the scalar isovector a0(980) resonance as dynamically generated in coupled channels, and demanding that the recently measured e+ e- -> phi(1020) f0(980) cross section is reproduced. For some realistic choices of the parameters, the presence of a dynamically generated isovector companion of the Y(2175) is revealed. We have also investigated the corrections to the e+ e- -> phi(1020) pi0 eta reaction cross section that arise from phi(1020)a0(980) re-scattering in the final state. They are typically large and modify substantially the cross section. For a suitable choice of parameters, the presence of the resonance would manifest itself as a clear peak at sqrt{s}~2.03 GeV in e+ e- -> phi(1020) pi0 eta.
Temporal coupled-mode theory for Fano resonance in light scattering by a single obstacle
Ruan, Zhichao
2009-01-01
We present a theory for Fano interference in light scattering by individual obstacle, based on a temporal coupled-mode formalism. This theory is applicable for obstacles that are much smaller than the incident wavelength, or for systems with two-dimensional cylindrical or three-dimensional spherical symmetry. We show that for each angle momentum channel, the Fano interference effect can be modeled by a simple temporal coupled-mode equation, which provides a line shape formula for scattering and absorption cross-section. We validate the analysis with numerical simulations. As an application of the theory, we design a structure that exhibits strong absorption and weak scattering properties at the same frequency.
Ding, Yadan; Cong, Tie; Chu, Xueying; Jia, Yan; Hong, Xia; Liu, Yichun
2016-07-01
Highly sensitive, specific, and selective immunoassays are of great significance for not only clinical diagnostics but also food safety, environmental monitoring, and so on. Enzyme-linked immunosorbent assays and fluorescence-based and electrochemical immunoassays are important intensively investigated immunoassay techniques. However, they might suffer from low sensitivity or false-positive results. In this work, a simple, reliable, and ultrasensitive magnetic-bead-based immunoassay was performed using biofunctionalized ZnS semiconductor nanocrystals as resonant Raman probes. The resonant Raman scattering of ZnS nanocrystals displays evenly spaced multi-phonon resonant Raman lines with narrow bandwidths and has strong resistance to environmental variation due to the nature of the electron-phonon interaction, thus rendering reliable signal readout in the immunoassays. The superparamagnetic Fe3O4 nanoparticles facilitated greatly the separation, purification, and concentration processes. It is beneficial for both reducing the labor intensity and amplifying the detection signals. The immobilization of antibodies on the surface of magnetic beads, the preparation of resonant Raman probes, and the immunological recognition between the antibody and analyte all occurred in the liquid phase, which minimized the diffusion barriers and boundary layer constraints. All these factors contributed to the ultralow detection limit of human IgG, which was determined to be about 0.5 fM (∼0.08 pg/ml). It is nearly the highest sensitivity obtained for IgG detection. This work shall facilitate the design of nanoplatforms for ultrasensitive detections of proteins, DNAs, bacteria, explosives, and so on. Graphical abstract An ultrasensitive magnetic-bead-based immunoassay was performed using multi-phonon resonant Raman lines of ZnS nanoparticles as detection signals. PMID:27173389
Investigation of the electronic structure of CuO by means of resonant X-ray Raman scattering
Doering, G
2001-01-01
excited state. By means of a perturbation theoretical treatment of the Coulomb interaction between the core-hole and the 3d-electrons an expression for the cross-section of the shakeup-process is derived. Thereby the observed excitation energy dependence of the shakeup-satellite's intensity and its position in the energy loss spectrum can be explained. Furthermore, its intensity shows a strong dependence on the scattering angle in certain scattering geometries. By means of a model calculation this dependence is attributed to a polarisation-effect. In this thesis the electronic structure of CuO is investigated utilizing resonant X-ray Raman Scattering. The special properties of this transition metal oxide are emphasized and the potential of the method is shown. First it is explained how one can draw conclusions about the unoccupied density of states of CuO and its symmetry from measurements of the copper K-alpha fluorescence by using an excitation energy of a few eV below the absorption threshold. By this mean...
DEFF Research Database (Denmark)
Rusch, W.; Appel-Hansen, Jørgen; Klein, C;
1976-01-01
constraint points. An experimental technique using a forward-scattering range is used to measure the IFR's of square and circular cylinders in an anechoic chamber. These experimental results are compared with the theory, and their implications on aperture blocking losses and boresight cross polarization...
Statistical distribution of resonance parameters for inelastic scattering of fast neutrons
International Nuclear Information System (INIS)
This paper deals with the application of statistical method for the analysis of nuclear reactions related to complex nuclei. It is shown that inelastic neutron scattering which occurs by creation of a complex nucleus in the higher energy range can be treated by statistical approach
Pygmy dipole resonance in 124Sn populated by inelastic scattering of 17O
Directory of Open Access Journals (Sweden)
L. Pellegri
2014-11-01
Full Text Available The γ decay from the high-lying states of 124Sn was measured using the inelastic scattering of 17O at 340 MeV. The emitted γ rays were detected with high resolution with the AGATA demonstrator array and the scattered ions were detected in two segmented ΔE–E silicon telescopes. The angular distribution was measured both for the γ rays and the scattered 17O ions. An accumulation of E1 strength below the particle threshold was found and compared with previous data obtained with (γ,γ′ and (α,α′γ reactions. The present results of elastic scattering, and excitation of E2 and E1 states were analysed using the DWBA approach. From this comprehensive description the isoscalar component of the 1− excited states was extracted. The obtained values are based on the comparison of the data with DWBA calculations including a form factor deduced using a microscopic transition density.
Pygmy dipole resonance in {sup 124}Sn populated by inelastic scattering of {sup 17}O
Energy Technology Data Exchange (ETDEWEB)
Pellegri, L. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Bracco, A., E-mail: angela.bracco@mi.infn.it [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Crespi, F.C.L.; Leoni, S.; Camera, F. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Lanza, E.G. [INFN Sezione di Catania, I-95123 Catania (Italy); Kmiecik, M.; Maj, A. [The Henryk Niewodniczański Institute of Nuclear Physics, PAN, 31-342 Krakow (Poland); Avigo, R. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Benzoni, G.; Blasi, N.; Boiano, C. [INFN Sezione di Milano, I-20133 Milano (Italy); Bottoni, S. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Brambilla, S. [INFN Sezione di Milano, I-20133 Milano (Italy); Ceruti, S. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); Giaz, A.; Million, B. [INFN Sezione di Milano, I-20133 Milano (Italy); Morales, A.I.; Nicolini, R.; Vandone, V. [INFN Sezione di Milano, I-20133 Milano (Italy); Dipartimento di Fisica, Università degli studi di Milano, I-20133 Milano (Italy); and others
2014-11-10
The γ decay from the high-lying states of {sup 124}Sn was measured using the inelastic scattering of {sup 17}O at 340 MeV. The emitted γ rays were detected with high resolution with the AGATA demonstrator array and the scattered ions were detected in two segmented ΔE–E silicon telescopes. The angular distribution was measured both for the γ rays and the scattered {sup 17}O ions. An accumulation of E1 strength below the particle threshold was found and compared with previous data obtained with (γ,γ{sup ′}) and (α,α{sup ′}γ) reactions. The present results of elastic scattering, and excitation of E2 and E1 states were analysed using the DWBA approach. From this comprehensive description the isoscalar component of the 1{sup −} excited states was extracted. The obtained values are based on the comparison of the data with DWBA calculations including a form factor deduced using a microscopic transition density.
Rong, Zhen; Wang, Chongwen; Wang, Junfeng; Wang, Donggen; Xiao, Rui; Wang, Shengqi
2016-10-15
A surface-enhanced resonance Raman scattering (SERRS) sensor was developed for the ultrasensitive detection of cancer biomarkers. Capture antibody-coated silver shell magnetic nanoparticles (Fe3O4@Ag MNPs) were utilized as the CEA enrichment platform and the SERRS signal amplification substrate. Gold nanorods (AuNRs) were coated with a thin silver shell to be in resonance with the resonant Raman dye diethylthiatricarbocyanine iodide (DTTC) and the excitation wavelength at 785nm. The silver-coated AuNRs (Au@Ag NRs) were then modified with detection antibody as the SERRS tags. Sandwich immune complexes formed in the presence of the target biomarker carcinoembryonic antigen (CEA), and this formation induced the plasmonic coupling between the Au@Ag NRs and Fe3O4@Ag MNPs. The SERRS signal of DTTC molecules located in the coupled plasmonic nanostructures was significantly enhanced. As a result, the proposed SERRS sensor was able to detect CEA with a low limit of detection of 4.75fg/mL and a wide dynamic linear range from 10fg/mL to 100ng/mL. The sensor provides a novel SERRS strategy for trace analyte detection and has a potential for clinical applications. PMID:27149164
One-Dimensional Discrete Stark Hamiltonian and Resonance Scattering by Impurities
Dmitrieva, L A; Melnikov, Yu B; Kuperin, Yu.A.; Melnikov, Yu.B.
1997-01-01
A one-dimensional discrete Stark Hamiltonian with a continuous electric field is constructed by extension theory methods. In absence of the impurities the model is proved to be exactly solvable, the spectrum is shown to be simple, continuous, filling the real axis; the eigenfunctions, the resolvent and the spectral measure are constructed explicitly. For this (unperturbed) system the resonance spectrum is shown to be empty. The model considering impurity in a single node is also constructed using the operator extension theory methods. The spectral analysis is performed and the dispersion equation for the resolvent singularities is obtained. The resonance spectrum is shown to contain infinite discrete set of resonances. One-to-one correspondence of the constructed Hamiltonian to some Lee-Friedrichs model is established.
Search for narrow resonances in $\\pi p$ elastic scattering from the EPECUR experiment
Gridnev, A; Andreev, V A; Bordyuzhin, I G; Briscoe, W J; Filimonov, Ye A; Golubev, V V; Kalinkin, D V; Koroleva, L I; Kozlenko, N G; Kozlov, V S; Krivshich, A G; Kuznetsov, V A; Morozov, B V; Nesterov, V M; Novinsky, D V; Ryltsov, V V; Sadler, M; Strakovsky, I I; Sulimov, A D; Sumachev, V V; Svirida, D N; Tarakanov, V I; Trautman, V Yu; Workman, R L
2016-01-01
The analysis of high-precision $\\pi^{\\pm}p \\to \\pi^{\\pm}p$ cross section data from the EPECUR Collaboration based on the multichannel $K$-matrix approach is presented.The sharp structures seen in these data are studied in terms of both opening thresholds and new resonance contributions. Some prominent features are found to be due to the opening $K\\Sigma$ channel. However, a complete description of the data is improved with the addition of two narrow resonant structures at $W\\sim 1.686$ and $W\\sim 1.720$ GeV. These structures are interpreted as manifestations of $S_{11}$ and $P_{11}$ resonances. The underlying nature of the observed phenomena is discussed.
Wang*, Hai; Li, Shujing; Zhang, Chunhong; Xie, Changde; Peng, Kunchi
2009-01-01
The laser spectroscopy with a narrow linewidth and high signal to noise ratio (S/N) is very important in the precise measurement of optical frequencies. Here, we present a novel high-resolution backward resonance Bragg-scattering (RBS) spectroscopy from a population difference grating (PDG). The PDG is formed by a standing-wave (SW) pump field in thermal 87Rb vapor, which periodically modulates the space population distribution of two levels in the 87Rb D1 line. A probe beam, having the identical frequency and the orthogonal polarization with the SW pump field, is Bragg-scattered by the PDG. Such Bragg-scattered light becomes stronger at an atomic resonance transition, which forms the RBS spectrum with a high S/N and sub-natural linewidth. Using the scheme of the coherent superposition of the individual Rayleigh-scattered light emitted from the atomic dipole oscillators on the PDG, the experimentally observed RBS spectroscopy is theoretically explained.
International Nuclear Information System (INIS)
Complete γ-decay in the 12C(12C,γ)24Mg and 12C(16O,γ)28Si reactions has been measured at energies close to the Coulomb Barrier using the DRAGON spectrometer and its associated BGO γ-array at the TRIUMF facility. The experimental data show an important feeding of doorway states around 10-11 MeV in both reactions. Comparisons with simulations allow to extract the full capture cross section and the main spin involved in the process. Different models are confronted to the results: completely statistical, semi-statistical with an unique entrance spin and cluster. The resolution of the BGO enables to eliminate a fully statistical scenario but is not enough to disentangle the two remaining scenarios. It is shown that the future PARIS array composed of the recently developed LaBr3 scintillators will have capabilities to distinguish between these two scenarios. (authors)
International Nuclear Information System (INIS)
A complete description of vector Bessel (vortex) beams in the context of the generalized Lorenz–Mie theory (GLMT) for the electromagnetic (EM) resonance scattering by a dielectric sphere is presented, using the method of separation of variables and the subtraction of a non-resonant background (corresponding to a perfectly conducting sphere of the same size) from the standard Mie scattering coefficients. Unlike the conventional results of standard optical radiation, the resonance scattering of a dielectric sphere in air in the field of EM Bessel beams is examined and demonstrated with particular emphasis on the EM field’s polarization and beam order (or topological charge). Linear, circular, radial, azimuthal polarizations as well as unpolarized Bessel vortex beams are considered. The conditions required for the resonance scattering are analyzed, stemming from the vectorial description of the EM field using the angular spectrum decomposition, the derivation of the beam-shape coefficients (BSCs) using the integral localized approximation (ILA) and Neumann–Graf’s addition theorem, and the determination of the scattering coefficients of the sphere using Debye series. In contrast with the standard scattering theory, the resonance method presented here allows the quantitative description of the scattering using Debye series by separating diffraction effects from the external and internal reflections from the sphere. Furthermore, the analysis is extended to include rainbow formation in Bessel beams and the derivation of a generalized formula for the deviation angle of high-order rainbows. Potential applications for this analysis include Bessel beam-based laser imaging spectroscopy, atom cooling and quantum optics, electromagnetic instrumentation and profilometry, optical tweezers and tractor beams, to name a few emerging areas of research
Energy Technology Data Exchange (ETDEWEB)
Mitri, F.G., E-mail: F.G.Mitri@ieee.org [Chevron, Area 52 Technology–ETC, 5 Bisbee Ct., Santa Fe, NM 87508 (United States); Li, R.X., E-mail: rxli@mail.xidian.edu.cn [School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071 (China); Collaborative Innovation Center of Information Sensing and Understanding, Xidian University, Xi’an 710071 (China); Guo, L.X. [School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071 (China); Collaborative Innovation Center of Information Sensing and Understanding, Xidian University, Xi’an 710071 (China); Ding, C.Y. [School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071 (China)
2015-10-15
A complete description of vector Bessel (vortex) beams in the context of the generalized Lorenz–Mie theory (GLMT) for the electromagnetic (EM) resonance scattering by a dielectric sphere is presented, using the method of separation of variables and the subtraction of a non-resonant background (corresponding to a perfectly conducting sphere of the same size) from the standard Mie scattering coefficients. Unlike the conventional results of standard optical radiation, the resonance scattering of a dielectric sphere in air in the field of EM Bessel beams is examined and demonstrated with particular emphasis on the EM field’s polarization and beam order (or topological charge). Linear, circular, radial, azimuthal polarizations as well as unpolarized Bessel vortex beams are considered. The conditions required for the resonance scattering are analyzed, stemming from the vectorial description of the EM field using the angular spectrum decomposition, the derivation of the beam-shape coefficients (BSCs) using the integral localized approximation (ILA) and Neumann–Graf’s addition theorem, and the determination of the scattering coefficients of the sphere using Debye series. In contrast with the standard scattering theory, the resonance method presented here allows the quantitative description of the scattering using Debye series by separating diffraction effects from the external and internal reflections from the sphere. Furthermore, the analysis is extended to include rainbow formation in Bessel beams and the derivation of a generalized formula for the deviation angle of high-order rainbows. Potential applications for this analysis include Bessel beam-based laser imaging spectroscopy, atom cooling and quantum optics, electromagnetic instrumentation and profilometry, optical tweezers and tractor beams, to name a few emerging areas of research.
Search for 28Si cluster states through the 12C+16O radiative capture
Courtin, S; Haas, F; Lebhertz, D; Jenkins, D G; Hutcheon, D A; Davis, C; Ruiz, C
2012-01-01
The 12C+16O resonant radiative capture reaction has been studied at 5 bombarding energies between Elab = 15.4 and 21.4 MeV, around the Coulomb barrier, at the Triumf laboratory (Vancouver, Canada) using the Dragon 0{\\deg} spectrometer and the associated BGO array. The most remarquable result is the previously unobserved decay path through 28Si doorway states of energies around 12 MeV leading to the measurement of new capture cross-sections. The feeding of specific, deformed states in 28Si from the resonances is discussed, as well as the selective feeding of 1^+ T=1 states around 11 MeV.
Scattering Resonance States and Partial Potential Energy Surface of Reaction I+HI(v=0)→IH(v′=0)+I
Institute of Scientific and Technical Information of China (English)
SUN Xiao-min; WANG Hua-yang; CAI Zheng-ting; FENG Da-cheng; BIAN Wen-sheng
2005-01-01
The partial potential energy surface of the I+HI→IH+I reaction involving the translational and vibrational motions has been constructed at the QCISD(T)//MP4SDQ level with the pseudo potential method that is helpful to interpreting the scattering resonance states. The lifetimes of the scattering resonance states in the title reaction obtained from the partial potential energy surface are about 90-120 fs, which agrees with the result of high-resolved threshold photodetachment spectroscopy of anion IHI- measured by Neumark.
International Nuclear Information System (INIS)
The experimental part of this report consists of measuring the optical absorbance of a collection of silver oblate spheroidal particulates as a function of wavelength, polarization, and angle of incidence. The method of producing such a collection is described along with measuring a few of the important characteristics like particle size, separation, and density. The experimental data are then compared with theoretical absorbances calculated using scattering and absorption cross sections. The cross sections are derived using a dipole approximation. 46 refs., 26 figs
Narrow 'barrier-resonance' states in elastic α-particle scattering
International Nuclear Information System (INIS)
Groups of narrow states with a rotational-like structure are observed from the Coulomb barrier up to an excitation energy of about 35 MeV in 28 Si. The properties of these states observed in α-particle elastic scattering will be described. There are a few, if any, models on the market that are able to explain the experimental findings in a consistent way. (author)
Collective Thomson scattering of a high power electron cyclotron resonance heating beam in LHD
DEFF Research Database (Denmark)
Kubo, S.; Nishiura, M.; Tanaka, K.;
2010-01-01
Collective Thomson scattering (CTS) system has been constructed at LHD making use of the high power ECRH system in LHD. The necessary features for CTS, high power probing beams and receiving beams, both with well defined Gaussian profile and with the fine controllability, are endowed in the ECRH ...... and applied to derive the bulk and high energy ion components for several combinations of NBI heated plasmas....
Frequency shifts of resonant modes of the Sun due to near-surface convective scattering
Bhattacharya, Jishnu; Antia, H M
2015-01-01
Measurements of oscillation frequencies of the Sun and stars can provide important independent constraints on their internal structure and dynamics. Seismic models of these oscillations are used to connect structure and rotation of the star to its resonant frequencies, which are then compared with observations, the goal being that of minimizing the difference between the two. Even in the case of the Sun, for which structure models are highly tuned, observed frequencies show systematic deviations from modeled frequencies, a phenomenon referred to as the "surface term." The dominant source of this systematic effect is thought to be vigorous near-surface convection, which is not well accounted for in both stellar modeling and mode-oscillation physics. Here we bring to bear the method of homogenization, applicable in the asymptotic limit of large wavelengths (in comparison to the correlation scale of convection), to characterize the effect of small-scale surface convection on resonant-mode frequencies in the Sun....
Resonant scattering and charm showers in ultrahigh-energy neutrino interactions
Wilczek, F.
1985-01-01
Electron antineutrinos with energy of about 7 x 10 to the 6th GeV have much-enhanced cross sections due to W-boson production off electrons. Possible signals due to cosmic-ray sources are estimated. Higher-energy antineutrinos can efficiently produce a W accompanied by radiation. Another possibility, which could lead to shadowing at modest depths, is resonant production of a charged Higgs particle. The importance of muon production by charm showers in rock is pointed out.
International Nuclear Information System (INIS)
Resonant inelastic X-ray scattering (RIXS) technique is applied to gain insight into the local electronic structure in liquid phase. The approach combines a liquid micro-jet and an X-ray emission spectrometer (XES) both installed in the recently developed LiXEdrom experimental station. Here we demonstrate how the combined approach enables investigation of the hydrogen bonding network in water and of chemical bonding in different solvents. In addition, the probe of energy transfer and electron dynamics at the metal–solvent interface is achieved by comparing the integrated RIXS intensities of the different radiative decay channels of the 2p core-hole of 3d transition-metals. The integrated RIXS intensities build the partial and the inverse partial X-ray fluorescence yields that allow for absorption measurements free from background signal of other elements or saturation effects
Lu, Y.; Frano, A.; Bluschke, M.; Hepting, M.; Macke, S.; Strempfer, J.; Wochner, P.; Cristiani, G.; Logvenov, G.; Habermeier, H.-U.; Haverkort, M. W.; Keimer, B.; Benckiser, E.
2016-04-01
We present a combined study of Ni K -edge resonant x-ray scattering and density functional calculations to probe and distinguish electronically driven ordering and lattice distortions in nickelate heterostructures. We demonstrate that due to the low crystal symmetry, contributions from structural distortions can contribute significantly to the energy-dependent Bragg peak intensities of a bond-ordered NdNiO3 reference film. For a LaNiO3-LaAlO3 superlattice that exhibits magnetic order, we establish a rigorous upper bound on the bond-order parameter. We thus conclusively confirm predictions of a dominant spin density wave order parameter in metallic nickelates with a quasi-two-dimensional electronic structure.
Malinina, L V; Augustyniak, W; Boivin, M; Boyard, J L; Dahl, R; Drews, M; Ellegaard, C; Fahri, L; Gaarde, C; Hennino, T; Jourdain, J C; Kagarlis, M A; Kravtsov, A V; Künne, R A; Larsen, J C; Morsch, P; Mylnikov, V A; Orichtchin, E M; Perdrisat, C F; Piskunov, N M; Prokofiev, A N; Punjabi, V; Radvanyi, P; Ramstein, B; Razmyslovich, B V; Roy-Stephan, M; Sitnik, I M; Skousen, M; Strokovsky, E A; Tkach, I I; Tomasi-Gustafsson, E; Volkov, S S; Zhdanov, A A; Zupranski, P
2001-01-01
A study of inelastic scattering of polarized 3.73 GeV/c deuterons on protons in the energy region of the Roper N*(1440) and the {DELTA}(1232) resonances excitation has been performed in an exclusive experiment at LNS (Laboratoire National SATURNE, Saclay, France) using the SPES-{pi} setup.Tensor and vector analyzing powers of pion production for the reactions d + p {\\to} d + n + pi^{+}, d + p {\\to} d + p + pi^{0}, d + p {\\to} d + N + pi pi have been measured as functions of the squared deuteron 4-momentum transfer t, of the effective mass of the subsystems (N pi), (N pi pi) and of the pion emission angle. A strong dependence of these analyzing powers upon the pion emission angle is observed. It is found that A_{yy} values for the considered reaction channels are systematically larger than the known inclusive {p (d, d {\\prime}) X} world data at the nearest beam energy.
International Nuclear Information System (INIS)
An avalanche photodiode detector has been commissioned to measure weak resonant x-ray magnetic scattering (RXMS) from induced magnetic polarizations in Cu layers in exchange-coupled Co/Cu multilayers using circularly polarized x-rays from synchrotron sources. The detector can count x-rays at rates of 107 photons s-1, giving good estimates of the RXMS at superlattice Bragg peaks in a reasonably short time when count losses due to the time structure of the synchrotron x-rays are corrected for. RXMS superlattice Bragg peaks as small as 1 x 10-4 in flipping ratio have been measured from a Co/Cu multilayer at the K absorption edge of Cu. The data are fitted by an oscillatory model magnetization profile in the Cu layers derived from a Ruderman-Kittel-Kasuya-Yosida theory of exchange coupling adapted to a planar geometry
Quasi-zero dimensional CuB2O4: a resonant inelastic X-ray scattering case study
Energy Technology Data Exchange (ETDEWEB)
Hancock, J.N.
2010-04-29
We explore the general phenomenology of resonant inelastic scattering (RIXS) using CuB{sub 2}O{sub 4}, a network of CuO{sub 4} plaquettes electronically isolated by B{sup +3} ions. Spectra show a small number of well-separated features, and we exploit the simple electronic structure to explore RIXS phenomenology by developing a calculation which allows for intermediate-state effects ignored in standard approaches. These effects are found to be non-negligible and good correspondence between our model and experiment leads to a simple picture of such phenomenology as the genesis of d {yields} d excitations at the K edge and intermediate-state interference effects.