The relation between the photonuclear E1 sum rule and the effective orbital g-factor
Energy Technology Data Exchange (ETDEWEB)
Bentz, Wolfgang E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Arima, Akito
2004-05-17
The connection between the enhancement factor (1+{kappa}) of the photonuclear E1 sum rule and the orbital angular momentum g-factor (g{sub l}) of a bound nucleon is investigated in the framework of the Landau-Migdal theory for isospin asymmetric nuclear matter. Special emphasis is put on the role of gauge invariance to establish the {kappa}-g{sub l} relation. By identifying the physical processes which are taken into account in {kappa} and g{sub l}, the validity and limitations of this relation will be discussed. The connections to the collective excitations and to nuclear Compton scattering are also shown.
International Nuclear Information System (INIS)
Arenhoevel, H.; Drechsel, D.; Weber, H.J.
1978-01-01
Generalized sum rules are derived by integrating the electromagnetic structure functions along lines of constant ratio of momentum and energy transfer. For non-relativistic systems these sum rules are related to the conventional photonuclear sum rules by a scaling transformation. The generalized sum rules are connected with the absorptive part of the forward scattering amplitude of virtual photons. The analytic structure of the scattering amplitudes and the possible existence of dispersion relations have been investigated in schematic relativistic and non-relativistic models. While for the non-relativistic case analyticity does not hold, the relativistic scattering amplitude is analytical for time-like (but not for space-like) photons and relations similar to the Gell-Mann-Goldberger-Thirring sum rule exist. (Auth.)
DEFF Research Database (Denmark)
T. Frandsen, Mads; Masina, Isabella; Sannino, Francesco
2011-01-01
We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models.......We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models....
Damanik, Asan
2018-03-01
Neutrino mass sum-rele is a very important research subject from theoretical side because neutrino oscillation experiment only gave us two squared-mass differences and three mixing angles. We review neutrino mass sum-rule in literature that have been reported by many authors and discuss its phenomenological implications.
'Sum rules' for preequilibrium reactions
International Nuclear Information System (INIS)
Hussein, M.S.
1981-03-01
Evidence that suggests a correct relationship between the optical transmission matrix, P, and the several correlation widths, gamma sub(n), found in nsmission matrix, P, and the several correlation widths, n, found in multistep compound (preequilibrium) nuclear reactions, is presented. A second sum rule is also derived within the shell model approach to nuclear reactions. Indications of the potential usefulness of the sum rules in preequilibrium studies are given. (Author) [pt
Sum rules in classical scattering
International Nuclear Information System (INIS)
Bolle, D.; Osborn, T.A.
1981-01-01
This paper derives sum rules associated with the classical scattering of two particles. These sum rules are the analogs of Levinson's theorem in quantum mechanics which provides a relationship between the number of bound-state wavefunctions and the energy integral of the time delay of the scattering process. The associated classical relation is an identity involving classical time delay and an integral over the classical bound-state density. We show that equalities between the Nth-order energy moment of the classical time delay and the Nth-order energy moment of the classical bound-state density hold in both a local and a global form. Local sum rules involve the time delay defined on a finite but otherwise arbitrary coordinate space volume S and the bound-state density associated with this same region. Global sum rules are those that obtain when S is the whole coordinate space. Both the local and global sum rules are derived for potentials of arbitrary shape and for scattering in any space dimension. Finally the set of classical sum rules, together with the known quantum mechanical analogs, are shown to provide a unified method of obtaining the high-temperature expansion of the classical, respectively the quantum-mechanical, virial coefficients
Sum rules for collisional processes
International Nuclear Information System (INIS)
Oreg, J.; Goldstein, W.H.; Bar-Shalom, A.; Klapisch, M.
1991-01-01
We derive level-to-configuration sum rules for dielectronic capture and for collisional excitation and ionization. These sum rules give the total transition rate from a detailed atomic level to an atomic configuration. For each process, we show that it is possible to factor out the dependence on continuum-electron wave functions. The remaining explicit level dependence of each rate is then obtained from the matrix element of an effective operator acting on the bound orbitals only. In a large class of cases, the effective operator reduces to a one-electron monopole whose matrix element is proportional to the statistical weight of the level. We show that even in these cases, nonstatistical level dependence enters through the dependence of radial integrals on continuum orbitals. For each process, explicit analytic expressions for the level-to-configuration sum rules are given for all possible cases. Together with the well-known J-file sum rule for radiative rates [E. U. Condon and G. H. Shortley, The Theory of Atomic Spectra (University Press, Cambridge, 1935)], the sum rules offer a systematic and efficient procedure for collapsing high-multiplicity configurations into ''effective'' levels for the purpose of modeling the population kinetics of ionized heavy atoms in plasma
Polarizability sum rules in QED
International Nuclear Information System (INIS)
Llanta, E.; Tarrach, R.
1978-01-01
The well founded total photoproduction and the, assumed subtraction free, longitudinal photoproduction polarizability sum rules are checked in QED at the lowest non-trivial order. The first one is shown to hold, whereas the second one turns out to need a subtraction, which makes its usefulness for determining the electromagnetic polarizabilities of the nucleons quite doubtful. (Auth.)
International Nuclear Information System (INIS)
Frandsen, Mads T.; Masina, Isabella; Sannino, Francesco
2011-01-01
We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays; we show how they can be used to predict the positron fraction at energies not yet explored by current experiments, and to constrain specific models.
Sum rules for neutrino oscillations
International Nuclear Information System (INIS)
Kobzarev, I.Yu.; Martemyanov, B.V.; Okun, L.B.; Schepkin, M.G.
1981-01-01
Sum rules for neutrino oscillations are obtained. The derivation of the general form of the s matrix for two stage process lsub(i)sup(-)→ν→lsub(k)sup(+-) (where lsub(i)sup(-)e, μ, tau, ... are initial leptons with flavor i and lsub(k)sup(+-) is final lepton) is presented. The consideration of two stage process lsub(i)sup(-)→ν→lsub(k)sup(+-) gives the possibility to take into account neutrino masses and to obtain the expressions for the oscillating cross sections. In the case of Dirac and left-handed Majorana neutrino is obtained the sum rule for the quantities 1/Vsub(K)σ(lsub(i)sup(-)→lsub(K)sup(+-)), (where Vsub(K) is a velocity of lsub(K)). In the left-handed Majorana neutrino case there is an additional antineutrino admixture leading to lsub(i)sup(-)→lsub(K)sup(+) process. Both components (neutrino and antineutrino) oscillate independently. The sums Σsub(K)1/Vsub(k)σ(lsub(i)sup(-) - lsub(K)sup(+-) then oscillate due to the presence of left-handed antineutrinos and right-handed neutrinos which do not take part in weak interactions. If right-handed currents are added sum rules analogous to considered above may be obtained. All conclusions are valid in the general case when CP is not conserved [ru
Momentum sum rules for fragmentation functions
International Nuclear Information System (INIS)
Meissner, S.; Metz, A.; Pitonyak, D.
2010-01-01
Momentum sum rules for fragmentation functions are considered. In particular, we give a general proof of the Schaefer-Teryaev sum rule for the transverse momentum dependent Collins function. We also argue that corresponding sum rules for related fragmentation functions do not exist. Our model-independent analysis is supplemented by calculations in a simple field-theoretical model.
QCD Sum Rules, a Modern Perspective
Colangelo, Pietro; Colangelo, Pietro; Khodjamirian, Alexander
2001-01-01
An introduction to the method of QCD sum rules is given for those who want to learn how to use this method. Furthermore, we discuss various applications of sum rules, from the determination of quark masses to the calculation of hadronic form factors and structure functions. Finally, we explain the idea of the light-cone sum rules and outline the recent development of this approach.
Sum rules in the response function method
International Nuclear Information System (INIS)
Takayanagi, Kazuo
1990-01-01
Sum rules in the response function method are studied in detail. A sum rule can be obtained theoretically by integrating the imaginary part of the response function over the excitation energy with a corresponding energy weight. Generally, the response function is calculated perturbatively in terms of the residual interaction, and the expansion can be described by diagrammatic methods. In this paper, we present a classification of the diagrams so as to clarify which diagram has what contribution to which sum rule. This will allow us to get insight into the contributions to the sum rules of all the processes expressed by Goldstone diagrams. (orig.)
Superconvergent sum rules for the normal reflectivity
International Nuclear Information System (INIS)
Furuya, K.; Zimerman, A.H.; Villani, A.
1976-05-01
Families of superconvergent relations for the normal reflectivity function are written. Sum rules connecting the difference of phases of the reflectivities of two materials are also considered. Finally superconvergence relations and sum rules for magneto-reflectivity in the Faraday and Voigt regimes are also studied
Current algebra sum rules for Reggeons
Carlitz, R
1972-01-01
The interplay between the constraints of chiral SU/sub 2/*SU/sub 2/ symmetry and Regge asymptotic behaviour is investigated. The author reviews the derivation of various current algebra sum rules in a study of the reaction pi + alpha to pi + beta . These sum rules imply that all particles may be classified in multiplets of SU/sub 2/*SU/sub 2/ and that each of these multiplets may contain linear combinations of an infinite number of physical states. Extending his study to the reaction pi + alpha to pi + pi + beta , he derives new sum rules involving commutators of the axial charge with the reggeon coupling matrices of the rho and f Regge trajectories. Some applications of these new sum rules are noted, and the general utility of these and related sum rules is discussed. (17 refs).
Study of QCD medium by sum rules
Energy Technology Data Exchange (ETDEWEB)
Mallik, S [Saha Institute of Nuclear Physics, Calcutta (India)
1998-08-01
Though it has no analogue in condensed matter physics, the thermal QCD sum rules can, nevertheless, answer questions of condensed matter type about the QCD medium. The ingredients needed to write such sum rules, viz. the operator product expansion and the spectral representation at finite temperature, are reviewed in detail. The sum rules are then actually written for the case of correlation function of two vector currents. Collecting information on the thermal average of the higher dimension operators from other sources, we evaluate these sum rules for the temperature dependent {rho}-meson parameters. Possibility of extracting more information from the combined set of all sum rules from different correlation functions is also discussed. (author) 30 refs., 2 figs.
Fixed mass and scaling sum rules
International Nuclear Information System (INIS)
Ward, B.F.L.
1975-01-01
Using the correspondence principle (continuity in dynamics), the approach of Keppell-Jones-Ward-Taha to fixed mass and scaling current algebraic sum rules is extended so as to consider explicitly the contributions of all classes of intermediate states. A natural, generalized formulation of the truncation ideas of Cornwall, Corrigan, and Norton is introduced as a by-product of this extension. The formalism is illustrated in the familiar case of the spin independent Schwinger term sum rule. New sum rules are derived which relate the Regge residue functions of the respective structure functions to their fixed hadronic mass limits for q 2 → infinity. (Auth.)
A Bayesian analysis of QCD sum rules
International Nuclear Information System (INIS)
Gubler, Philipp; Oka, Makoto
2011-01-01
A new technique has recently been developed, in which the Maximum Entropy Method is used to analyze QCD sum rules. This approach has the virtue of being able to directly generate the spectral function of a given operator, without the need of making an assumption about its specific functional form. To investigate whether useful results can be extracted within this method, we have first studied the vector meson channel, where QCD sum rules are traditionally known to provide a valid description of the spectral function. Our results show a significant peak in the region of the experimentally observed ρ-meson mass, which is in agreement with earlier QCD sum rules studies and suggests that the Maximum Entropy Method is a strong tool for analyzing QCD sum rules.
Sum rules for nuclear collective excitations
International Nuclear Information System (INIS)
Bohigas, O.
1978-07-01
Characterizations of the response function and of integral properties of the strength function via a moment expansion are discussed. Sum rule expressions for the moments in the RPA are derived. The validity of these sum rules for both density independent and density dependent interactions is proved. For forces of the Skyrme type, analytic expressions for the plus one and plus three energy weighted sum rules are given for isoscalar monopole and quadrupole operators. From these, a close relationship between the monopole and quadrupole energies is shown and their dependence on incompressibility and effective mass is studied. The inverse energy weighted sum rule is computed numerically for the monopole operator, and an upper bound for the width of the monopole resonance is given. Finally the reliability of moments given by the RPA with effective interactions is discussed using simple soluble models for the hamiltonian, and also by comparison with experimental data
3He electron scattering sum rules
International Nuclear Information System (INIS)
Kim, Y.E.; Tornow, V.
1982-01-01
Electron scattering sum rules for 3 He are derived with a realistic ground-state wave function. The theoretical results are compared with the experimentally measured integrated cross sections. (author)
Gaussian sum rules for optical functions
International Nuclear Information System (INIS)
Kimel, I.
1981-12-01
A new (Gaussian) type of sum rules (GSR) for several optical functions, is presented. The functions considered are: dielectric permeability, refractive index, energy loss function, rotatory power and ellipticity (circular dichroism). While reducing to the usual type of sum rules in a certain limit, the GSR contain in general, a Gaussian factor that serves to improve convergence. GSR might be useful in analysing experimental data. (Author) [pt
The Gross-Llewellyn Smith sum rule
International Nuclear Information System (INIS)
Scott, W.G.
1981-01-01
We present the most recent data on the Gross-Llewellyn Smith sum rule obtained from the combined BEBC Narrow Band Neon and GGM-PS Freon neutrino/antineutrino experiments. The data for the Gross-Llewellyn Smith sum rule as a function of q 2 suggest a smaller value for the QCD coupling constant parameter Λ than is obtained from the analysis of the higher moments. (author)
Electronuclear sum rules for the lightest nuclei
International Nuclear Information System (INIS)
Efros, V.D.
1992-01-01
It is shown that the model-independent longitudinal electronuclear sum rules for nuclei with A = 3 and A = 4 have an accuracy on the order of a percent in the traditional single-nucleon approximation with free nucleons for the nuclear charge-density operator. This makes it possible to test this approximation by using these sum rules. The longitudinal sum rules for A = 3 and A = 4 are calculated using the wave functions of these nuclei corresponding to a large set of realistic NN interactions. The values of the model-independent sum rules lie in the range of values calculated by this method. Model-independent expressions are obtained for the transverse sum rules for nuclei with A = 3 and A = 4. These sum rules are calculated using a large set of realistic wave functions of these nuclei. The contribution of the convection current and the changes in the results for different versions of realistic NN forces are given. 29 refs., 4 tabs
Transition sum rules in the shell model
Lu, Yi; Johnson, Calvin W.
2018-03-01
An important characterization of electromagnetic and weak transitions in atomic nuclei are sum rules. We focus on the non-energy-weighted sum rule (NEWSR), or total strength, and the energy-weighted sum rule (EWSR); the ratio of the EWSR to the NEWSR is the centroid or average energy of transition strengths from an nuclear initial state to all allowed final states. These sum rules can be expressed as expectation values of operators, which in the case of the EWSR is a double commutator. While most prior applications of the double commutator have been to special cases, we derive general formulas for matrix elements of both operators in a shell model framework (occupation space), given the input matrix elements for the nuclear Hamiltonian and for the transition operator. With these new formulas, we easily evaluate centroids of transition strength functions, with no need to calculate daughter states. We apply this simple tool to a number of nuclides and demonstrate the sum rules follow smooth secular behavior as a function of initial energy, as well as compare the electric dipole (E 1 ) sum rule against the famous Thomas-Reiche-Kuhn version. We also find surprising systematic behaviors for ground-state electric quadrupole (E 2 ) centroids in the s d shell.
Sum rules for quasifree scattering of hadrons
Peterson, R. J.
2018-02-01
The areas d σ /d Ω of fitted quasifree scattering peaks from bound nucleons for continuum hadron-nucleus spectra measuring d2σ /d Ω d ω are converted to sum rules akin to the Coulomb sums familiar from continuum electron scattering spectra from nuclear charge. Hadronic spectra with or without charge exchange of the beam are considered. These sums are compared to the simple expectations of a nonrelativistic Fermi gas, including a Pauli blocking factor. For scattering without charge exchange, the hadronic sums are below this expectation, as also observed with Coulomb sums. For charge exchange spectra, the sums are near or above the simple expectation, with larger uncertainties. The strong role of hadron-nucleon in-medium total cross sections is noted from use of the Glauber model.
QCD sum rules in a Bayesian approach
International Nuclear Information System (INIS)
Gubler, Philipp; Oka, Makoto
2011-01-01
A novel technique is developed, in which the Maximum Entropy Method is used to analyze QCD sum rules. The main advantage of this approach lies in its ability of directly generating the spectral function of a given operator. This is done without the need of making an assumption about the specific functional form of the spectral function, such as in the 'pole + continuum' ansatz that is frequently used in QCD sum rule studies. Therefore, with this method it should in principle be possible to distinguish narrow pole structures form continuum states. To check whether meaningful results can be extracted within this approach, we have first investigated the vector meson channel, where QCD sum rules are traditionally known to provide a valid description of the spectral function. Our results exhibit a significant peak in the region of the experimentally observed ρ-meson mass, which agrees with earlier QCD sum rules studies and shows that the Maximum Entropy Method is a useful tool for analyzing QCD sum rules.
A bayesian approach to QCD sum rules
International Nuclear Information System (INIS)
Gubler, Philipp; Oka, Makoto
2010-01-01
QCD sum rules are analyzed with the help of the Maximum Entropy Method. We develop a new technique based on the Bayesion inference theory, which allows us to directly obtain the spectral function of a given correlator from the results of the operator product expansion given in the deep euclidean 4-momentum region. The most important advantage of this approach is that one does not have to make any a priori assumptions about the functional form of the spectral function, such as the 'pole + continuum' ansatz that has been widely used in QCD sum rule studies, but only needs to specify the asymptotic values of the spectral function at high and low energies as an input. As a first test of the applicability of this method, we have analyzed the sum rules of the ρ-meson, a case where the sum rules are known to work well. Our results show a clear peak structure in the region of the experimental mass of the ρ-meson. We thus demonstrate that the Maximum Entropy Method is successfully applied and that it is an efficient tool in the analysis of QCD sum rules. (author)
Vacuum structure and QCD sum rules
International Nuclear Information System (INIS)
Shifman, M.A.
1992-01-01
The method of the QCD sum rules was and still is one of the most productive tools in a wide range of problems associated with the hadronic phenomenology. Many heuristic ideas, computational devices, specific formulae which are useful to theorists working not only in hadronic physics, have been accumulated in this method. Some of the results and approaches which have originally been developed in connection with the QCD sum rules can be and are successfully applied in related fields, as supersymmetric gauge theories, nontraditional schemes of quarks and leptons, etc. The amount of literature on these and other more basic problems in hadronic physics has grown enormously in recent years. This volume presents a collection of papers which provide an overview of all basic elements of the sum rule approach and priority has been given to the works which seemed most useful from a pedagogical point of view
Inverse-moment chiral sum rules
International Nuclear Information System (INIS)
Golowich, E.; Kambor, J.
1996-01-01
A general class of inverse-moment sum rules was previously derived by the authors in a chiral perturbation theory (ChPT) study at two-loop order of the isospin and hypercharge vector-current propagators. Here, we address the evaluation of the inverse-moment sum rules in terms of existing data and theoretical constraints. Two kinds of sum rules are seen to occur: those which contain as-yet undetermined O(q 6 ) counterterms and those free of such quantities. We use the former to obtain phenomenological evaluations of two O(q 6 ) counterterms. Light is shed on the important but difficult issue regarding contributions of higher orders in the ChPT expansion. copyright 1996 The American Physical Society
Systematics of strength function sum rules
Directory of Open Access Journals (Sweden)
Calvin W. Johnson
2015-11-01
Full Text Available Sum rules provide useful insights into transition strength functions and are often expressed as expectation values of an operator. In this letter I demonstrate that non-energy-weighted transition sum rules have strong secular dependences on the energy of the initial state. Such non-trivial systematics have consequences: the simplification suggested by the generalized Brink–Axel hypothesis, for example, does not hold for most cases, though it weakly holds in at least some cases for electric dipole transitions. Furthermore, I show the systematics can be understood through spectral distribution theory, calculated via traces of operators and of products of operators. Seen through this lens, violation of the generalized Brink–Axel hypothesis is unsurprising: one expects sum rules to evolve with excitation energy. Furthermore, to lowest order the slope of the secular evolution can be traced to a component of the Hamiltonian being positive (repulsive or negative (attractive.
Vacuum structure and QCD sum rules
International Nuclear Information System (INIS)
Shifman, M.A.
1992-01-01
The method of the QCD sum rules was and still is one of the most productive tools in a wide range of problems associated with the hadronic phenomenology. Many heuristic ideas, computational devices, specific formulae which are useful to theorists working not only in hadronic physics, have been accumulated in this method. Some of the results and approaches which have been originally developed in connection with the QCD sum rules can be and are successfully applied in related fields, such as supersymmetric gauge theories, nontraditional schemes of quarks and leptons, etc. The amount of literature on these and other more basic problems in hadronic physics has grown enormously in recent years. This collection of papers provides an overview of all basic elements of the sum rule approach. Priority has been given to those works which seemed most useful from a pedagogical point of view
Sum rules for the quarkonium systems
International Nuclear Information System (INIS)
Burnel, A.; Caprasse, H.
1980-01-01
In the framework of the radial Schroedinger equation we derive in a very simple way sum rules relating the potential to physical quantities such as the energy eigenvalues and the square of the lth derivative of the eigenfunctions at the origin. These sum rules contain as particular cases well-known results such as the quantum version of the Clausius theorem in classical mechanics as well as Kramers's relations for the Coulomb potential. Several illustrations are given and the possibilities of applying them to the quarkonium systems are considered
Integrals of Lagrange functions and sum rules
Energy Technology Data Exchange (ETDEWEB)
Baye, Daniel, E-mail: dbaye@ulb.ac.be [Physique Quantique, CP 165/82, Universite Libre de Bruxelles, B 1050 Bruxelles (Belgium); Physique Nucleaire Theorique et Physique Mathematique, CP 229, Universite Libre de Bruxelles, B 1050 Bruxelles (Belgium)
2011-09-30
Exact values are derived for some matrix elements of Lagrange functions, i.e. orthonormal cardinal functions, constructed from orthogonal polynomials. They are obtained with exact Gauss quadratures supplemented by corrections. In the particular case of Lagrange-Laguerre and shifted Lagrange-Jacobi functions, sum rules provide exact values for matrix elements of 1/x and 1/x{sup 2} as well as for the kinetic energy. From these expressions, new sum rules involving Laguerre and shifted Jacobi zeros and weights are derived. (paper)
Pentaquarks in QCD Sum Rule Approach
International Nuclear Information System (INIS)
Rodrigues da Silva, R.; Matheus, R.D.; Navarra, F.S.; Nielsen, M.
2004-01-01
We estimate the mass of recently observed pentaquak staes Ξ- (1862) and Θ+(1540) using two kinds of interpolating fields, containing two highly correlated diquarks, in the QCD sum rule approach. We obtained good agreement with the experimental value, using standard continuum threshold
Sum rule approach to nuclear vibrations
International Nuclear Information System (INIS)
Suzuki, T.
1983-01-01
Velocity field of various collective states is explored by using sum rules for the nuclear current. It is shown that an irrotational and incompressible flow model is applicable to giant resonance states. Structure of the hydrodynamical states is discussed according to Tomonaga's microscopic theory for collective motions. (author)
Old tensor mesons in QCD sum rules
International Nuclear Information System (INIS)
Aliev, T.M.; Shifman, M.A.
1981-01-01
Tensor mesons f, A 2 and A 3 are analyzed within the framework of QCD sum rules. The effects of gluon and quark condensate is accounted for phenomenologically. Accurate estimates of meson masses and coupling constants of the lowest-lying states are obtained. It is shown that the masses are reproduced within theoretical uncertainty of about 80 MeV. The coupling of f meson to the corresponding quark current is determined. The results are in good aqreement with experimental data [ru
Singlet axial constant from QCD sum rules
International Nuclear Information System (INIS)
Belitskij, A.V.; Teryaev, O.V.
1995-01-01
We analyze the singlet axial form factor of the proton for small momentum transferred in the framework of QCD sum rules using the interpolating nucleon current which explicitly accounts for the gluonic degrees of freedom. As the result we come to the quantitative prediction of the singlet axial constant. It is shown that the bilocal power corrections play the most important role in the analysis. 21 refs., 3 figs
Beautiful mesons from QCD spectral sum rules
International Nuclear Information System (INIS)
Narison, S.
1991-01-01
We discuss the beautiful meson from the point of view of the QCD spectral sum rules (QSSR). The bottom quark mass and the mixed light quark-gluon condensates are determined quite accurately. The decay constant f B is estimated and we present some arguments supporting this result. The decay constants and the masses of the other members of the beautiful meson family are predicted. (orig.)
Limiting law excess sum rule for polyelectrolytes.
Landy, Jonathan; Lee, YongJin; Jho, YongSeok
2013-11-01
We revisit the mean-field limiting law screening excess sum rule that holds for rodlike polyelectrolytes. We present an efficient derivation of this law that clarifies its region of applicability: The law holds in the limit of small polymer radius, measured relative to the Debye screening length. From the limiting law, we determine the individual ion excess values for single-salt electrolytes. We also consider the mean-field excess sum away from the limiting region, and we relate this quantity to the osmotic pressure of a dilute polyelectrolyte solution. Finally, we consider numerical simulations of many-body polymer-electrolyte solutions. We conclude that the limiting law often accurately describes the screening of physical charged polymers of interest, such as extended DNA.
Robinson's radiation damping sum rule: Reaffirmation and extension
International Nuclear Information System (INIS)
Mane, S.R.
2011-01-01
Robinson's radiation damping sum rule is one of the classic theorems of accelerator physics. Recently Orlov has claimed to find serious flaws in Robinson's proof of his sum rule. In view of the importance of the subject, I have independently examined the derivation of the Robinson radiation damping sum rule. Orlov's criticisms are without merit: I work through Robinson's derivation and demonstrate that Orlov's criticisms violate well-established mathematical theorems and are hence not valid. I also show that Robinson's derivation, and his damping sum rule, is valid in a larger domain than that treated by Robinson himself: Robinson derived his sum rule under the approximation of a small damping rate, but I show that Robinson's sum rule applies to arbitrary damping rates. I also display more concise derivations of the sum rule using matrix differential equations. I also show that Robinson's sum rule is valid in the vicinity of a parametric resonance.
Isospin sum rules for inclusive cross-sections
Rotelli, P.; Suttorp, L.G.
1972-01-01
A systematic analysis of isospin sum rules is presented for the distribution functions of strong, electromagnetic weak inclusive processes. The general expression for these sum rules is given and some new examples are presented.
Sum rules in extended RPA theories
International Nuclear Information System (INIS)
Adachi, S.; Lipparini, E.
1988-01-01
Different moments m k of the excitation strength function are studied in the framework of the second RPA and of the extended RPA in which 2p2h correlations are explicitly introduced into the ground state by using first-order perturbation theory. Formal properties of the equations of motion concerning sum rules are derived and compared with those exhibited by the usual 1p1h RPA. The problem of the separation of the spurious solutions in extended RPA calculations is also discussed. (orig.)
Nuclear Symmetry Energy with QCD Sum Rule
International Nuclear Information System (INIS)
Jeong, K.S.; Lee, S.H.
2013-01-01
We calculate the nucleon self-energies in an isospin asymmetric nuclear matter using QCD sum rule. Taking the difference of these for the neutron and proton enables us to express an important part of the nuclear symmetry energy in terms of local operators. Calculating the operator product expansion up to mass dimension six operators, we find that the main contribution to the difference comes from the iso-vector scalar and vector operators, which is reminiscent to the case of relativistic mean field type theories where mesons with aforementioned quantum numbers produce the difference and provide the dominant mechanism for nuclear symmetry energy. (author)
QCD sum-rules for V-A spectral functions
International Nuclear Information System (INIS)
Chakrabarti, J.; Mathur, V.S.
1980-01-01
The Borel transformation technique of Shifman et al is used to obtain QCD sum-rules for V-A spectral functions. In contrast to the situation in the original Weinberg sum-rules and those of Bernard et al, the problem of saturating the sum-rules by low lying resonances is brought under control. Furthermore, the present sum-rules, on saturation, directly determine useful phenomenological parameters
Sum rules for charge transition density
Energy Technology Data Exchange (ETDEWEB)
Gul' karov, I S [Tashkentskij Politekhnicheskij Inst. (USSR)
1979-01-01
The form factors of the quadrupole and octupole oscillations of the /sup 12/C nucleus are compared with the predictions of the sum rules for the charge transition density (CTD). These rules allow one to obtain various CTDs which contain the components k: r/sup lambda + 2k-2/rho(r) and r/sup lambda + 2k-1)(drho(r)/dr) (k = 0, 1, 2...) and can be applied to analyze the inelastic scattering of high energy particles by nuclei. It is shown that the CTD under consideration have different radius dependence and describe the data essentially better (though ambiguously) than the Tassy and Steinwedel-Jensen models do. Recurrence formulas are derived for the ratios of the higher-order transition matrix elements and CTD. These formulas can be used to predict the CTD behavior for highly excited nuclear states.
On sum rules for charge transition density
International Nuclear Information System (INIS)
Gul'karov, I.S.
1979-01-01
The form factors of the quadrupole and octupole oscillations of the 12 C nucleus are compared with the predictions of the sum rules for the charge transition density (CTD). These rules allow to obtain various CTD which contain the components k: rsup(lambda+2k-2)rho(r) and rsup(lambda+2k-1)(drho(r)/dr) (k=0, 1, 2...) and can be applied to analyze the inelastic scattering of high energy particles by nuclei. It is shown that the CTD under consideration have different radius dependence and describe the data essentially better (though ambiguously) than the Tassy and Steinwedel-Jensen models do. The recurrent formulas are derived for the ratios of the higher order transition matrix elements and CTD. These formulas can be used to predict the CTD behaviour for highly excited nuclear states
International Nuclear Information System (INIS)
Oblozinsky, Pavel
2002-01-01
We review the current status of photonuclear data, in particular in the light of recent major progress in developing internationally recognized library of evaluated photonuclear reaction data. The paper covers all aspects of photonuclear data, including experiments, photonuclear reaction theory, evaluation procedures, review of national photonuclear libraries, and description of the major IAEA library as well as its validation. This major library, prepared to suit transport calculations, contains data in the ENDF-6 format for 164 materials evaluated mostly up to 150 MeV. (author)
Neutron matter within QCD sum rules
Cai, Bao-Jun; Chen, Lie-Wen
2018-05-01
The equation of state (EOS) of pure neutron matter (PNM) is studied in QCD sum rules (QCDSRs ). It is found that the QCDSR results on the EOS of PNM are in good agreement with predictions by current advanced microscopic many-body theories. Moreover, the higher-order density terms in quark condensates are shown to be important to describe the empirical EOS of PNM in the density region around and above nuclear saturation density although they play a minor role at subsaturation densities. The chiral condensates in PNM are also studied, and our results indicate that the higher-order density terms in quark condensates, which are introduced to reasonably describe the empirical EOS of PNM at suprasaturation densities, tend to hinder the appearance of chiral symmetry restoration in PNM at high densities.
Light cone sum rules in nonabelian gauge field theory
Energy Technology Data Exchange (ETDEWEB)
Mallik, S [Bern Univ. (Switzerland). Inst. fuer Theoretische Physik
1981-03-24
The author examines, in the context of nonabelian gauge field theory, the derivation of the light cone sum rules which were obtained earlier on the assumption of dominance of canonical singularity in the current commutator on the light cone. The retarded scaling functions appearing in the sum rules are numbers known in terms of the charges of the quarks and the number of quarks and gluons in the theory. Possible applications of the sum rules are suggested.
On the Laplace transform of the Weinberg type sum rules
International Nuclear Information System (INIS)
Narison, S.
1981-09-01
We consider the Laplace transform of various sum rules of the Weinberg type including the leading non-perturbative effects. We show from the third type Weinberg sum rules that 7.5 to 8.9 1 coupling to the W boson, while the second sum rule gives an upper bound on the A 1 mass (Msub(A 1 ) < or approx. 1.25 GeV). (author)
Inclusive sum rules and spectra of neutrons at the ISR
International Nuclear Information System (INIS)
Grigoryan, A.A.
1975-01-01
Neutron spectra in pp collisions at ISR energies are studied in the framework of sum rules for inclusive processes. The contributions of protons, π- and E- mesons to the energy sum rule are calculated at √5 = 53 GeV. It is shown by means of this sum rule that the spectra of neutrons at the ISR are in contradiction with the spectra of other particles also measured at the ISR
Singular f-sum rule for superfluid 4He
International Nuclear Information System (INIS)
Wong, V.K.
1979-01-01
The validity and applicability to inelastic neutron scattering of a singular f-sum rule for superfluid helium, proposed by Griffin to explain the rhosub(s) dependence in S(k, ω) as observed by Woods and Svensson, are examined in the light of similar sum rules rigorously derived for anharmonic crystals and Bose liquids. It is concluded that the singular f-sum rules are only of microscopic interest. (Auth,)
Coulomb sum rules in the relativistic Fermi gas model
International Nuclear Information System (INIS)
Do Dang, G.; L'Huillier, M.; Nguyen Giai, Van.
1986-11-01
Coulomb sum rules are studied in the framework of the Fermi gas model. A distinction is made between mathematical and observable sum rules. Differences between non-relativistic and relativistic Fermi gas predictions are stressed. A method to deduce a Coulomb response function from the longitudinal response is proposed and tested numerically. This method is applied to the 40 Ca data to obtain the experimental Coulomb sum rule as a function of momentum transfer
Sum rules and constraints on passive systems
International Nuclear Information System (INIS)
Bernland, A; Gustafsson, M; Luger, A
2011-01-01
A passive system is one that cannot produce energy, a property that naturally poses constraints on the system. A system in convolution form is fully described by its transfer function, and the class of Herglotz functions, holomorphic functions mapping the open upper half-plane to the closed upper half-plane, is closely related to the transfer functions of passive systems. Following a well-known representation theorem, Herglotz functions can be represented by means of positive measures on the real line. This fact is exploited in this paper in order to rigorously prove a set of integral identities for Herglotz functions that relate weighted integrals of the function to its asymptotic expansions at the origin and infinity. The integral identities are the core of a general approach introduced here to derive sum rules and physical limitations on various passive physical systems. Although similar approaches have previously been applied to a wide range of specific applications, this paper is the first to deliver a general procedure together with the necessary proofs. This procedure is described thoroughly and exemplified with examples from electromagnetic theory.
QCD sum rules and applications to nuclear physics
International Nuclear Information System (INIS)
Cohen, T.D.; Xuemin, J.
1994-12-01
Applications of QCD sum-rule methods to the physics of nuclei are reviewed, with an emphasis on calculations of baryon self-energies in infinite nuclear matter. The sum-rule approach relates spectral properties of hadrons propagating in the finite-density medium, such as optical potentials for quasinucleons, to matrix elements of QCD composite operators (condensates). The vacuum formalism for QCD sum rules is generalized to finite density, and the strategy and implementation of the approach is discussed. Predictions for baryon self-energies are compared to those suggested by relativistic nuclear physics phenomenology. Sum rules for vector mesons in dense nuclear matter are also considered. (author)
Adler Function, DIS sum rules and Crewther Relations
International Nuclear Information System (INIS)
Baikov, P.A.; Chetyrkin, K.G.; Kuehn, J.H.
2010-01-01
The current status of the Adler function and two closely related Deep Inelastic Scattering (DIS) sum rules, namely, the Bjorken sum rule for polarized DIS and the Gross-Llewellyn Smith sum rule are briefly reviewed. A new result is presented: an analytical calculation of the coefficient function of the latter sum rule in a generic gauge theory in order O(α s 4 ). It is demonstrated that the corresponding Crewther relation allows to fix two of three colour structures in the O(α s 4 ) contribution to the singlet part of the Adler function.
Model dependence of energy-weighted sum rules
International Nuclear Information System (INIS)
Kirson, M.W.
1977-01-01
The contribution of the nucleon-nucleon interaction to energy-weighted sum rules for electromagnetic multipole transitions is investigated. It is found that only isoscalar electric transitions might have model-independent energy-weighted sum rules. For these transitions, explicit momentum and angular momentum dependence of the nuclear force give rise to corrections to the sum rule which are found to be negligibly small, thus confirming the model independence of these specific sum rules. These conclusions are unaffected by correlation effects. (author)
Lattice QCD evaluation of baryon magnetic moment sum rules
International Nuclear Information System (INIS)
Leinweber, D.B.
1991-05-01
Magnetic moment combinations and sum rules are evaluated using recent results for the magnetic moments of octet baryons determined in a numerical simulation of quenched QCD. The model-independent and parameter-free results of the lattice calculations remove some of the confusion and contradiction surrounding past magnetic moment sum rule analyses. The lattice results reveal the underlying quark dynamics investigated by magnetic moment sum rules and indicate the origin of magnetic moment quenching for the non-strange quarks in Σ. In contrast to previous sum rule analyses, the magnetic moments of nonstrange quarks in Ξ are seen to be enhanced in the lattice results. In most cases, the spin-dependent dynamics and center-of-mass effects giving rise to baryon dependence of the quark moments are seen to be sufficient to violate the sum rules in agreement with experimental measurements. In turn, the sum rules are used to further examine the results of the lattice simulation. The Sachs sum rule suggests that quark loop contributions not included in present lattice calculations may play a key role in removing the discrepancies between lattice and experimental ratios of magnetic moments. This is supported by other sum rules sensitive to quark loop contributions. A measure of the isospin symmetry breaking in the effective quark moments due to quark loop contributions is in agreement with model expectations. (Author) 16 refs., 2 figs., 2 tabs
Luttinger and Hubbard sum rules: are they compatible?
International Nuclear Information System (INIS)
Matho, K.
1992-01-01
A so-called Hubbard sum rule determines the weight of a satellite in fermionic single-particle excitations with strong local repulsion (U→∞). Together with the Luttinger sum rule, this imposes two different energy scales on the remaining finite excitations. In the Hubbard chain, this has been identified microscopically as being due to a separation of spin and charge. (orig.)
A sum rule description of giant resonances at finite temperature
International Nuclear Information System (INIS)
Meyer, J.; Quentin, P.; Brack, M.
1983-01-01
A generalization of the sum rule approach to collective motion at finite temperature is presented. The m 1 and msub(-1) sum rules for the isovector dipole and the isoscalar monopole electric modes have been evaluated with the modified SkM force for the 208 Pb nucleus. The variation of the resulting giant resonance energies with temperature is discussed. (orig.)
On contribution of instantons to nucleon sum rules
International Nuclear Information System (INIS)
Dorokhov, A.E.; Kochelev, N.I.
1989-01-01
The contribution of instantons to nucleon QCD sum rules is obtained. It is shown that this contribution does provide stabilization of the sum rules and leads to formation of a nucleon as a bound state of quarks in the instanton field. 17 refs.; 3 figs
Light cone sum rules for single-pion electroproduction
International Nuclear Information System (INIS)
Mallik, S.
1978-01-01
Light cone dispersion sum rules (of low energy and superconvergence types) are derived for nucleon matrix elements of the commutator involving electromagnetic and divergence of axial vector currents. The superconvergence type sum rules in the fixed mass limit are rewritten without requiring the knowledge of Regge subtractions. The retarded scaling functions occurring in these sum rules are evaluated within the framework of quark light cone algebra of currents. Besides a general consistency check of the framework underlying the derivation, the author infers, on the basis of crude evaluation of scaling functions, an upper limit of 100 MeV for the bare mass of nonstrange quarks. (Auth.)
Parity of Θ+(1540) from QCD sum rules
International Nuclear Information System (INIS)
Lee, Su Houng; Kim, Hungchong; Kwon, Youngshin
2005-01-01
The QCD sum rule for the pentaquark Θ + , first analyzed by Sugiyama, Doi and Oka, is reanalyzed with a phenomenological side that explicitly includes the contribution from the two-particle reducible kaon-nucleon intermediate state. The magnitude for the overlap of the Θ + interpolating current with the kaon-nucleon state is obtained by using soft-kaon theorem and a separate sum rule for the ground state nucleon with the pentaquark nucleon interpolating current. It is found that the K-N intermediate state constitutes only 10% of the sum rule so that the original claim that the parity of Θ + is negative remains valid
Neutrino mass sum rules and symmetries of the mass matrix
Energy Technology Data Exchange (ETDEWEB)
Gehrlein, Julia [Karlsruhe Institute of Technology, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); Universidad Autonoma de Madrid, Departamento de Fisica Teorica, Madrid (Spain); Instituto de Fisica Teorica UAM/CSIC, Madrid (Spain); Spinrath, Martin [Karlsruhe Institute of Technology, Institut fuer Theoretische Teilchenphysik, Karlsruhe (Germany); National Center for Theoretical Sciences, Physics Division, Hsinchu (China)
2017-05-15
Neutrino mass sum rules have recently gained again more attention as a powerful tool to discriminate and test various flavour models in the near future. A related question which has not yet been discussed fully satisfactorily was the origin of these sum rules and if they are related to any residual or accidental symmetry. We will address this open issue here systematically and find previous statements confirmed. Namely, the sum rules are not related to any enhanced symmetry of the Lagrangian after family symmetry breaking but they are simply the result of a reduction of free parameters due to skillful model building. (orig.)
Moessbauer sum rules for use with synchrotron sources
International Nuclear Information System (INIS)
Lipkin, Harry J.
1999-01-01
The availability of tunable synchrotron radiation sources with millivolt resolution has opened new prospects for exploring dynamics of complex systems with Moessbauer spectroscopy. Early Moessbauer treatments and moment sum rules are extended to treat inelastic excitations measured in synchrotron experiments, with emphasis on the unique new conditions absent in neutron scattering and arising in resonance scattering: prompt absorption, delayed emission, recoil-free transitions and coherent forward scattering. The first moment sum rule normalizes the inelastic spectrum. New sum rules obtained for higher moments include the third moment proportional to the second derivative of the potential acting on the Moessbauer nucleus and independent of temperature in the the harmonic approximation
Derivation of sum rules for quark and baryon fields
International Nuclear Information System (INIS)
Bongardt, K.
1978-01-01
In an analogous way to the Weinberg sum rules, two spectral-function sum rules for quark and baryon fields are derived by means of the concept of lightlike charges. The baryon sum rules are valid for the case of SU 3 as well as for SU 4 and the one-particle approximation yields a linear mass relation. This relation is not in disagreement with the normal linear GMO formula for the baryons. The calculated masses of the first resonance states agree very well with the experimental data
Adler-Weisberger sum rule for WLWL→WLWL scattering
International Nuclear Information System (INIS)
Pham, T.N.
1991-01-01
We analyse the Adler-Weisberger sum rule for W L W L →W L W L scattering. We find that at some energy, the W L W L total cross section must be large to saturate the sum rule. Measurements at future colliders would be needed to check the sum rule and to obtain the decay rates Γ(H→W L W L , Z L Z L ) which would be modified by the existence of a P-wave vector meson resonance in the standard model with strongly interacting Higgs sector or in technicolour models. (orig.)
Compton scattering from nuclei and photo-absorption sum rules
International Nuclear Information System (INIS)
Gorchtein, Mikhail; Hobbs, Timothy; Londergan, J. Timothy; Szczepaniak, Adam P.
2011-01-01
We revisit the photo-absorption sum rule for real Compton scattering from the proton and from nuclear targets. In analogy with the Thomas-Reiche-Kuhn sum rule appropriate at low energies, we propose a new 'constituent quark model' sum rule that relates the integrated strength of hadronic resonances to the scattering amplitude on constituent quarks. We study the constituent quark model sum rule for several nuclear targets. In addition, we extract the α=0 pole contribution for both proton and nuclei. Using the modern high-energy proton data, we find that the α=0 pole contribution differs significantly from the Thomson term, in contrast with the original findings by Damashek and Gilman.
A simple derivation of new sum rules of Bessel functions
International Nuclear Information System (INIS)
Ciocci, F.; Dattoli, G.; Dipace, A.
1985-01-01
In this note it is exploited a recently suggested technique to get simple expressions for a class of sum rules of Bessel functions appearing in plasma physics; their relevance to the numerical evaluation of the Turkin function is also discussed
QCD sum rules and applications to nuclear physics
Energy Technology Data Exchange (ETDEWEB)
Cohen, T D [Maryland Univ., College Park, MD (United States). Dept. of Physics; [Washington Univ., Seattle, WA (United States). Dept. of Physics and Inst. for Nuclear Theory; Furnstahl, R J [Ohio State Univ., Columbus, OH (United States). Dept. of Physics; Griegel, D K [Maryland Univ., College Park, MD (United States). Dept. of Physics; [TRIUMF, Vancouver, BC (Canada); Xuemin, J
1994-12-01
Applications of QCD sum-rule methods to the physics of nuclei are reviewed, with an emphasis on calculations of baryon self-energies in infinite nuclear matter. The sum-rule approach relates spectral properties of hadrons propagating in the finite-density medium, such as optical potentials for quasinucleons, to matrix elements of QCD composite operators (condensates). The vacuum formalism for QCD sum rules is generalized to finite density, and the strategy and implementation of the approach is discussed. Predictions for baryon self-energies are compared to those suggested by relativistic nuclear physics phenomenology. Sum rules for vector mesons in dense nuclear matter are also considered. (author). 153 refs., 8 figs.
Faraday effect revisited: sum rules and convergence issues
DEFF Research Database (Denmark)
Cornean, Horia; Nenciu, Gheorghe
2010-01-01
This is the third paper of a series revisiting the Faraday effect. The question of the absolute convergence of the sums over the band indices entering the Verdet constant is considered. In general, sum rules and traces per unit volume play an important role in solid-state physics, and they give...
QCD sum rule for nucleon in nuclear matter
International Nuclear Information System (INIS)
Mallik, S.; Sarkar, Sourav
2010-01-01
We consider the two-point function of nucleon current in nuclear matter and write a QCD sum rule to analyse the residue of the nucleon pole as a function of nuclear density. The nucleon self-energy needed for the sum rule is taken as input from calculations using phenomenological N N potential. Our result shows a decrease in the residue with increasing nuclear density, as is known to be the case with similar quantities. (orig.)
GDH sum rule measurement at low Q2
International Nuclear Information System (INIS)
Bianchi, N.
1996-01-01
The Gerasimov-Drell-Hearn (GDH) sum rule is based on a general dispersive relation for the forward Compton scattering. Multipole analysis suggested the possible violation of the sum rule. Some propositions have been made to modify the original GDH expression. An effort is now being made in several laboratories to shred some light on this topic. The purposes of the different planned experiments are briefly presented according to their Q 2 range
Spectral sum rule for time delay in R2
International Nuclear Information System (INIS)
Osborn, T.A.; Sinha, K.B.; Bolle, D.; Danneels, C.
1985-01-01
A local spectral sum rule for nonrelativistic scattering in two dimensions is derived for the potential class velement ofL 4 /sup // 3 (R 2 ). The sum rule relates the integral over all scattering energies of the trace of the time-delay operator for a finite region Σis contained inR 2 to the contributions in Σ of the pure point and singularly continuous spectra
Light-cone sum rules: A SCET-based formulation
De Fazio, F; Hurth, Tobias; Feldmann, Th.
2007-01-01
We describe the construction of light-cone sum rules (LCSRs) for exclusive $B$-meson decays into light energetic hadrons from correlation functions within soft-collinear effective theory (SCET). As an example, we consider the SCET sum rule for the $B \\to \\pi$ transition form factor at large recoil, including radiative corrections from hard-collinear loop diagrams at first order in the strong coupling constant.
Hadronic final states and sum rules in deep inelastic processes
International Nuclear Information System (INIS)
Pal, B.K.
1977-01-01
In order to get maximum information on the hadronic final states and sum rules in deep inelastic processes, Regge phenomenology and quarks parton model have been used. The unified picture for the production of hadrons of type i as a function of Bjorken and Feyman variables with only one adjustable parameter is formulated. The results of neutrino experiments and the production of charm particles are discussed in sum rules. (author)
Comment on QCD sum rules and weak bottom decays
International Nuclear Information System (INIS)
Guberina, B.; Machet, B.
1982-07-01
QCD sum rules derived by Bourrely et al. are applied to B-decays to get a lower and an upper bound for the decay rate. The sum rules are shown to be essentially controlled by the large mass scales involved in the process. These bounds combined with the experimental value of BR (B→eνX) provide an upper bound for the lifetime of the B + meson. A comparison is made with D-meson decays
Chiral corrections to the Adler-Weisberger sum rule
Beane, Silas R.; Klco, Natalie
2016-12-01
The Adler-Weisberger sum rule for the nucleon axial-vector charge, gA , offers a unique signature of chiral symmetry and its breaking in QCD. Its derivation relies on both algebraic aspects of chiral symmetry, which guarantee the convergence of the sum rule, and dynamical aspects of chiral symmetry breaking—as exploited using chiral perturbation theory—which allow the rigorous inclusion of explicit chiral symmetry breaking effects due to light-quark masses. The original derivations obtained the sum rule in the chiral limit and, without the benefit of chiral perturbation theory, made various attempts at extrapolating to nonvanishing pion masses. In this paper, the leading, universal, chiral corrections to the chiral-limit sum rule are obtained. Using PDG data, a recent parametrization of the pion-nucleon total cross sections in the resonance region given by the SAID group, as well as recent Roy-Steiner equation determinations of subthreshold amplitudes, threshold parameters, and correlated low-energy constants, the Adler-Weisberger sum rule is confronted with experimental data. With uncertainty estimates associated with the cross-section parametrization, the Goldberger-Treimann discrepancy, and the truncation of the sum rule at O (Mπ4) in the chiral expansion, this work finds gA=1.248 ±0.010 ±0.007 ±0.013 .
Spectral sum rules for the three-body problem
International Nuclear Information System (INIS)
Bolle, D.; Osborn, T.A.
1982-01-01
This paper derives a number of sum rules for nonrelativistic three-body scattering. These rules are valid for any finite region μ in the six-dimensional coordinate space. They relate energy moments of the trace of the onshell time-delay operator to the energy-weighted probability for finding the three-body bound-state wave functions in the region μ. If μ is all of the six-dimensional space, the global form of the sum rules is obtained. In this form the rules constitute higher-order Levinson's theorems for the three-body problem. Finally, the sum rules are extended to allow the energy momtns have complex powers
Sum Rules, Classical and Quantum - A Pedagogical Approach
Karstens, William; Smith, David Y.
2014-03-01
Sum rules in the form of integrals over the response of a system to an external probe provide general analytical tools for both experiment and theory. For example, the celebrated f-sum rule gives a system's plasma frequency as an integral over the optical-dipole absorption spectrum regardless of the specific spectral distribution. Moreover, this rule underlies Smakula's equation for the number density of absorbers in a sample in terms of the area under their absorption bands. Commonly such rules are derived from quantum-mechanical commutation relations, but many are fundamentally classical (independent of ℏ) and so can be derived from more transparent mechanical models. We have exploited this to illustrate the fundamental role of inertia in the case of optical sum rules. Similar considerations apply to sum rules in many other branches of physics. Thus, the ``attenuation integral theorems'' of ac circuit theory reflect the ``inertial'' effect of Lenz's Law in inductors or the potential energy ``storage'' in capacitors. These considerations are closely related to the fact that the real and imaginary parts of a response function cannot be specified independently, a result that is encapsulated in the Kramers-Kronig relations. Supported in part by the US Department of Energy, Office of Nuclear Physics under contract DE-AC02-06CH11357.
The black hole interior and a curious sum rule
International Nuclear Information System (INIS)
Giveon, Amit; Itzhaki, Nissan; Troost, Jan
2014-01-01
We analyze the Euclidean geometry near non-extremal NS5-branes in string theory, including regions beyond the horizon and beyond the singularity of the black brane. The various regions have an exact description in string theory, in terms of cigar, trumpet and negative level minimal model conformal field theories. We study the worldsheet elliptic genera of these three superconformal theories, and show that their sum vanishes. We speculate on the significance of this curious sum rule for black hole physics
The black hole interior and a curious sum rule
Energy Technology Data Exchange (ETDEWEB)
Giveon, Amit [Racah Institute of Physics, The Hebrew University,Jerusalem, 91904 (Israel); Itzhaki, Nissan [Physics Department, Tel-Aviv University,Ramat-Aviv, 69978 (Israel); Troost, Jan [Laboratoire de Physique Théorique,Unité Mixte du CRNS et de l’École Normale Supérieure,associée à l’Université Pierre et Marie Curie 6,UMR 8549 École Normale Supérieure,24 Rue Lhomond Paris 75005 (France)
2014-03-12
We analyze the Euclidean geometry near non-extremal NS5-branes in string theory, including regions beyond the horizon and beyond the singularity of the black brane. The various regions have an exact description in string theory, in terms of cigar, trumpet and negative level minimal model conformal field theories. We study the worldsheet elliptic genera of these three superconformal theories, and show that their sum vanishes. We speculate on the significance of this curious sum rule for black hole physics.
A Bayesian analysis of the nucleon QCD sum rules
International Nuclear Information System (INIS)
Ohtani, Keisuke; Gubler, Philipp; Oka, Makoto
2011-01-01
QCD sum rules of the nucleon channel are reanalyzed, using the maximum-entropy method (MEM). This new approach, based on the Bayesian probability theory, does not restrict the spectral function to the usual ''pole + continuum'' form, allowing a more flexible investigation of the nucleon spectral function. Making use of this flexibility, we are able to investigate the spectral functions of various interpolating fields, finding that the nucleon ground state mainly couples to an operator containing a scalar diquark. Moreover, we formulate the Gaussian sum rule for the nucleon channel and find that it is more suitable for the MEM analysis to extract the nucleon pole in the region of its experimental value, while the Borel sum rule does not contain enough information to clearly separate the nucleon pole from the continuum. (orig.)
Moessbauer sum rules for use with synchrotron sources
International Nuclear Information System (INIS)
Lipkin, H.J.
1995-01-01
The availability of tunable synchrotron radiation sources with millivolt resolution has opened prospects for exploring dynamics of complex systems with Moessbauer spectroscopy. Early Moessbauer treatments and moment sum rules are extended to treat inelastic excitations measured in synchrotron experiments, with emphasis on the unique conditions absent in neutron scattering and arising in resonance scattering: prompt absorption, delayed emission, recoilfree transitions, and coherent forward scattering. The first moment sum rule normalizes the inelastic spectrum. Sum rules obtained for higher moments include the third moment proportional to the second derivative of the potential acting on the Moessbauer nucleus and independent of temperature in the harmonic approximation. Interesting information may be obtained on the behavior of the potential acting on this nucleus in samples not easily investigated with neutron scattering, e.g., small samples, thin films, time-dependent structures, and amorphous-metallic high pressure phases
Dynamical local field, compressibility, and frequency sum rules for quasiparticles
International Nuclear Information System (INIS)
Morawetz, Klaus
2002-01-01
The finite temperature dynamical response function including the dynamical local field is derived within a quasiparticle picture for interacting one-, two-, and three-dimensional Fermi systems. The correlations are assumed to be given by a density-dependent effective mass, quasiparticle energy shift, and relaxation time. The latter one describes disorder or collisional effects. This parametrization of correlations includes local-density functionals as a special case and is therefore applicable for density-functional theories. With a single static local field, the third-order frequency sum rule can be fulfilled simultaneously with the compressibility sum rule by relating the effective mass and quasiparticle energy shift to the structure function or pair-correlation function. Consequently, solely local-density functionals without taking into account effective masses cannot fulfill both sum rules simultaneously with a static local field. The comparison to the Monte Carlo data seems to support such a quasiparticle picture
Chiral symmetry breaking parameters from QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Mallik, S [Karlsruhe Univ. (T.H.) (Germany, F.R.). Inst. fuer Theoretische Kernphysik; Bern Univ. (Switzerland). Inst. fuer Theoretische Physik)
1982-10-04
We obtain new QCD sum rules by considering vacuum expectation values of two-point functions, taking all the five quark bilinears into account. These sum rules are employed to extract values of different chiral symmetry breaking parameters in QCD theory. We find masses of light quarks, m=1/2msub(u)+msub(d)=8.4+-1.2 MeV, msub(s)=205+-65 MeV. Further, we obtain corrections to certain soft pion (kaon) PCAC relations and the violation of SU(3) flavour symmetry by the non-strange and strange quark-antiquark vacuum condensate.
Dispersion relations and sum rules for natural optical activity
International Nuclear Information System (INIS)
Thomaz, M.T.; Nussenzveig, H.M.
1981-06-01
Dispersion relations and sum rules are derived for the complex rotatory power of an arbitrary linear (nonmagnetic) isotropic medium showing natural optical activity. Both previously known dispersion relations and sum rules as well as new ones are obtained. It is shown that the Rosenfeld-Condon dispersion formula is inconsistent with the expected asymptotic behavior at high frequencies. A new dispersion formula based on quantum eletro-dynamics removes this inconsistency; however, it still requires modification in the low-frequency limit. (Author) [pt
Chiral restoration and the extended photoabsorption sum rule in nuclei
Energy Technology Data Exchange (ETDEWEB)
Ericson, M [Lyon-1 Univ., 69 - Villeurbanne (France). Inst. de Physique Nucleaire; [European Organization for Nuclear Research, Geneva (Switzerland); Rosa-Clot, M [Florence Univ. (Italy). Ist. di Fisica; [Istituto Nazionale di Fisica Nucleare, Florence (Italy); Kulagin, S A [Akademiya Meditsinskikh Nauk SSSR, Moscow (Russian Federation)
1996-07-01
The Bethe-Levinger sum rule is extended beyond the potential model. The pion degrees of freedom are taken into account and the modifications of the potential theory are analyzed within two different approaches: dipole sum rule and dispersion relation on the Compton amplitude. Our aim is to extract from the photon data experimental information on the expectation value of the square of the pion field, a quantity which enters also in the restoration of chiral symmetry in nuclei and in pion-nucleus scattering. We are led to incorporate in the description the {Delta} resonance, which is strongly excited by the pion degrees of freedom. 11 refs.
Chiral restoration and the extended photoabsorption sum rule in nuclei
International Nuclear Information System (INIS)
Ericson, M.; Rosa-Clot, M.; Kulagin, S.A.
1996-07-01
The Bethe-Levinger sum rule is extended beyond the potential model. The pion degrees of freedom are taken into account and the modifications of the potential theory are analyzed within two different approaches: dipole sum rule and dispersion relation on the Compton amplitude. Our aim is to extract from the photon data experimental information on the expectation value of the square of the pion field, a quantity which enters also in the restoration of chiral symmetry in nuclei and in pion-nucleus scattering. We are led to incorporate in the description the Δ resonance, which is strongly excited by the pion degrees of freedom
Counter-ions at single charged wall: Sum rules.
Samaj, Ladislav
2013-09-01
For inhomogeneous classical Coulomb fluids in thermal equilibrium, like the jellium or the two-component Coulomb gas, there exists a variety of exact sum rules which relate the particle one-body and two-body densities. The necessary condition for these sum rules is that the Coulomb fluid possesses good screening properties, i.e. the particle correlation functions or the averaged charge inhomogeneity, say close to a wall, exhibit a short-range (usually exponential) decay. In this work, we study equilibrium statistical mechanics of an electric double layer with counter-ions only, i.e. a globally neutral system of equally charged point-like particles in the vicinity of a plain hard wall carrying a fixed uniform surface charge density of opposite sign. At large distances from the wall, the one-body and two-body counter-ion densities go to zero slowly according to the inverse-power law. In spite of the absence of screening, all known sum rules are shown to hold for two exactly solvable cases of the present system: in the weak-coupling Poisson-Boltzmann limit (in any spatial dimension larger than one) and at a special free-fermion coupling constant in two dimensions. This fact indicates an extended validity of the sum rules and provides a consistency check for reasonable theoretical approaches.
Λ-bar from QCD sum rules for heavy quarkonium
International Nuclear Information System (INIS)
Kiselev, V.V.
1994-01-01
Using a specific scheme of the QCD sum rules for heavy quarkonium int he leading approximation over the inverse heavy quark, one gets the estimate of the difference between the masses of the heavy meson and heavy quark Λ=o.59+-0.02 GeV. 10 refs
Isospin sum rule for nuclear photoabsorption: Effect of retardation
International Nuclear Information System (INIS)
Maize, M.A.; Fallieros, S.
1987-01-01
Motivated by the close similarity between a sum rule originally derived by Cabibbo and Radicati and a simplified version based on nonrelativistic nuclear physics in the long-wavelength limit, we have investigated the effect of retardation corrections. An account of the contributions due to higher multipolarities is presented, together with a physical interpretation of the results
QCD Sum Rule External Field Approach and Vacuum Susceptibilities
Institute of Scientific and Technical Information of China (English)
ZONG Hong-Shi; PING Jia-Lun; CHANG Chao-His; WANG Fan; ZHAO En-Guang
2002-01-01
Based on QCD sum rule three-point and two-point external field formulas respectively, the vector vacuumsusceptibilities are calculated at the mean-field level in the framework of the global color symmetry model. It is shownthat the above two approaches of determination of the vector vacuum susceptibility may lead to different results. Thereason of this contradiction is discussed.
QCD sum rule studies at finite density and temperature
Energy Technology Data Exchange (ETDEWEB)
Kwon, Youngshin
2010-01-21
In-medium modifications of hadronic properties have a strong connection to the restoration of chiral symmetry in hot and/or dense medium. The in-medium spectral functions for vector and axial-vector mesons are of particular interest in this context, considering the experimental dilepton production data which signal the in-medium meson properties. In this thesis, finite energy sum rules are employed to set constraints for the in-medium spectral functions of vector and axial-vector mesons. Finite energy sum rules for the first two moments of the spectral functions are investigated with emphasis on the role of a scale parameter related to the spontaneous chiral symmetry breaking in QCD. It is demonstrated that these lowest moments of vector current spectral functions do permit an accurate sum rule analysis with controlled inputs, such as the QCD condensates of lowest dimensions. In contrast, the higher moments contain uncertainties from the higher dimensional condensates. It turns out that the factorization approximation for the four-quark condensate is not applicable in any of the cases studied in this work. The accurate sum rules for the lowest two moments of the spectral functions are used to clarify and classify the properties of vector meson spectral functions in a nuclear medium. Possible connections with the Brown-Rho scaling hypothesis are also discussed. (orig.)
Beauty vector meson decay constants from QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Lucha, Wolfgang [Institute for High Energy Physics, Austrian Academy of Sciences, Nikolsdorfergasse 18, A-1050 Vienna (Austria); Melikhov, Dmitri [Institute for High Energy Physics, Austrian Academy of Sciences, Nikolsdorfergasse 18, A-1050 Vienna (Austria); D. V. Skobeltsyn Institute of Nuclear Physics, M. V. Lomonosov Moscow State University, 119991, Moscow (Russian Federation); Simula, Silvano [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146, Roma (Italy)
2016-01-22
We present the outcomes of a very recent investigation of the decay constants of nonstrange and strange heavy-light beauty vector mesons, with special emphasis on the ratio of any such decay constant to the decay constant of the corresponding pseudoscalar meson, by means of Borel-transformed QCD sum rules. Our results suggest that both these ratios are below unity.
On QCD sum rules of the Laplace transform type and light quark masses
International Nuclear Information System (INIS)
Narison, S.
1981-04-01
We discuss the relation between the usual dispersion relation sum rules and the Laplace transform type sum rules in quantum chromodynamics. Two specific examples corresponding to the S-coupling constant sum rule and the light quark masses sum rules are considered. An interpretation, within QCD, of Leutwyler's formula for the current algebra quark masses is also given
Spectral function sum rules in quantum chromodynamics. I. Charged currents sector
International Nuclear Information System (INIS)
Floratos, E.G.; Narison, Stephan; Rafael, Eduardo de.
1978-07-01
The Weinberg sum rules of the algebra of currents are reconsidered in the light of quantum chromodynamics (QCD). The authors derive new finite energy sum rules which replace the old Weinberg sum rules. The new sum rules are convergent and the rate of convergence is explicitly calculated in perturbative QCD at the one loop approximation. Phenomenological applications of these sum rules in the charged current sector are also discussed
Proof of Kochen–Specker Theorem: Conversion of Product Rule to Sum Rule
International Nuclear Information System (INIS)
Toh, S.P.; Zainuddin, Hishamuddin
2009-01-01
Valuation functions of observables in quantum mechanics are often expected to obey two constraints called the sum rule and product rule. However, the Kochen–Specker (KS) theorem shows that for a Hilbert space of quantum mechanics of dimension d ≤ 3, these constraints contradict individually with the assumption of value definiteness. The two rules are not irrelated and Peres [Found. Phys. 26 (1996) 807] has conceived a method of converting the product rule into a sum rule for the case of two qubits. Here we apply this method to a proof provided by Mermin based on the product rule for a three-qubit system involving nine operators. We provide the conversion of this proof to one based on sum rule involving ten operators. (general)
Spectral representation and QCD sum rules in hot nuclear matter
International Nuclear Information System (INIS)
Mallik, S.; Sarkar, Sourav
2009-01-01
We construct the spectral representation of spinsor two-point functions in medium, that is, at finite temperature and chemical potential. We first deal with the free spinor two-point function. Then we construct the same for interacting fields leading to the Kaellen-Lehmann representation. It is emphasised that although these two point functions have the structure of 2 x 2 matrices in the real time formulation of field theory, any one component actually suffices to describe the dynamics of the system. Our construction is then applied to write the QCD sum rules for two-point function of nucleon currents in medium. We discuss a subtracted version to increase the sensitivity of such a sum rule and point out how it differs from a conventional one. (author)
Parton model (Moessbauer) sum rules for b → c decays
International Nuclear Information System (INIS)
Lipkin, H.J.
1993-01-01
The parton model is a starting point or zero-order approximation in many treatments. The author follows an approach previously used for the Moessbauer effect and shows how parton model sum rules derived for certain moments of the lepton energy spectrum in b → c semileptonic decays remain valid even when binding effects are included. The parton model appears as a open-quote semiclassical close-quote model whose results for certain averages also hold (correspondence principle) in quantum mechanics. Algebraic techniques developed for the Moessbauer effect exploit simple features of the commutator between the weak current operator and the bound state Hamiltonian to find the appropriate sum rules and show the validity of the parton model in the classical limit, ℎ → 0, where all commutators vanish
QCD sum rules for the decay amplitudes of pseudoscalar mesons
International Nuclear Information System (INIS)
Narison, S.
1981-07-01
Bounds on the π and K meson decay amplitudes are obtained to a good accuracy from QCD sum rules of the Laplace transform type. A relation between fsub(π) and the rho meson coupling to the photon is given. Using the heavy quarks q 2 =0 sum rule to two loops we find our best bounds: fsub(D) approximately < (101+-25) MeV and fsub(F) approximately < (147+-41.6) MeV to be compared to fsub(π) approximately 93.3 MeV. We also derive a relation between the D and F meson masses and the charm quark mass. Our results are extended to the beautiful B mesons. (author)
Sum rule limitations of kinetic particle-production models
International Nuclear Information System (INIS)
Knoll, J.; CEA Centre d'Etudes Nucleaires de Grenoble, 38; Guet, C.
1988-04-01
Photoproduction and absorption sum rules generalized to systems at finite temperature provide a stringent check on the validity of kinetic models for the production of hard photons in intermediate energy nuclear collisions. We inspect such models for the case of nuclear matter at finite temperature employed in a kinetic regime which copes those encountered in energetic nuclear collisions, and find photon production rates which significantly exceed the limits imposed by the sum rule even under favourable concession. This suggests that coherence effects are quite important and the production of photons cannot be considered as an incoherent addition of individual NNγ production processes. The deficiencies of present kinetic models may also apply for the production of probes such as the pion which do not couple perturbatively to the nuclear currents. (orig.)
More sum rules for quark and lepton masses
International Nuclear Information System (INIS)
Terazawa, Hidezumi.
1990-04-01
Sum rules for quark and lepton masses are derived from the Ward identity of Chanowitz and Ellis for the vertex function of the trace of the energy-momentum tensor and the two axial-vector currents and the partially conserved axial-vector current hypothesis. They indicate, among other things, that the constituent quark masses of u and d and those of the techniquarks, if any, are about 300 MeV and 300 GeV, respectively. (author)
Modified Adler sum rule and violation of charge symmetry
International Nuclear Information System (INIS)
Dominguez, C.A.; Moreno, H.; Zepeda, A.
The consequences of a once subtracted dispersion relation in the derivation of the Adler sum rule are investigated. It is shown that one can expect a breakdown of charge symmetry, of the isotriplet current hypothesis, and of scaling of the structure functions. These breakdowns are related to the possible presence of a non-zero subtraction function at asymptotic energies and arbitrary q 2 . Second class currents and PCAC relations are also discussed
Finite temperature QCD sum rule and the ρ-meson
International Nuclear Information System (INIS)
Liu Jueping; Jin Yaping
1995-01-01
The contributions from the three-gluon condensates to the finite temperature QCD sum rule for the ρ-meson are calculated, and then the dependence of the properties of the ρ-meson upon temperature is investigated in a string model of condensates. The results show that the parameters characterizing the properties of the ρ-meson change noticeably when the temperature closes to the critical temperature of the condensates, and if the critical temperatures of condensates are the same
Relativistic and Nuclear Medium Effects on the Coulomb Sum Rule.
Cloët, Ian C; Bentz, Wolfgang; Thomas, Anthony W
2016-01-22
In light of the forthcoming high precision quasielastic electron scattering data from Jefferson Lab, it is timely for the various approaches to nuclear structure to make robust predictions for the associated response functions. With this in mind, we focus here on the longitudinal response function and the corresponding Coulomb sum rule for isospin-symmetric nuclear matter at various baryon densities. Using a quantum field-theoretic quark-level approach which preserves the symmetries of quantum chromodynamics, as well as exhibiting dynamical chiral symmetry breaking and quark confinement, we find a dramatic quenching of the Coulomb sum rule for momentum transfers |q|≳0.5 GeV. The main driver of this effect lies in changes to the proton Dirac form factor induced by the nuclear medium. Such a dramatic quenching of the Coulomb sum rule was not seen in a recent quantum Monte Carlo calculation for carbon, suggesting that the Jefferson Lab data may well shed new light on the explicit role of QCD in nuclei.
Evaluating chiral symmetry restoration through the use of sum rules
Directory of Open Access Journals (Sweden)
Rapp Ralf
2012-11-01
Full Text Available We pursue the idea of assessing chiral restoration via in-medium modifications of hadronic spectral functions of chiral partners. The usefulness of sum rules in this endeavor is illustrated, focusing on the vector/axial-vector channel. We first present an update on obtaining quantitative results for pertinent vacuum spectral functions. These serve as a basis upon which the in-medium spectral functions can be constructed. A novel feature of our analysis of the vacuum spectral functions is the need to include excited resonances, dictated by satisfying the Weinberg-type sum rules. This includes excited states in both the vector and axial-vector channels.We also analyze the QCD sum rule for the finite temperature vector spectral function, based on a ρ spectral function tested in dilepton data which develops a shoulder at low energies.We find that the ρ′ peak flattens off which may be a sign of chiral restoration, though a study of the finite temperature axial-vector spectral function remains to be carried out.
B --> K$*\\gamma$ from hybrid sum rule
Narison, Stéphan
1994-01-01
Using the {\\it hybrid} moments-Laplace sum rule (HSR), which is well-defined for M_b \\rar \\infty, in contrast with the popular double Borel (Laplace) sum rule (DLSR), which blows up in this limit when applied to the heavy-to-light processes, we show that the form factor of the B \\rar K^* \\ \\gamma radiative transition is dominated by the light-quark condensate for M_b \\rar \\infty and behaves like \\sqrt M_b. The form factor is found to be F^{B\\rar K^*}_1(0) \\simeq (30.8 \\pm 1.3 \\pm 3.6 \\pm 0.6)\\times 10^{-2}, where the errors come respectively from the procedure in the sum rule analysis, the errors in the input and in the SU(3)_f-breaking parameters. This result leads to Br(B\\rar K^* \\ \\gamma) \\simeq (4.45 \\pm 1.12) \\times 10^{-5} in agreement with the recent CLEO data. Parametrization of the M_b-dependence of the form factor including the SU(3)_f-breaking effects is given in (26), which leads to F^{B\\rar K^*}_1(0)/ F^{B\\rar \\rho}_1(0) \\simeq (1.14 \\pm 0.02).
What do QCD sum rules tell us about dense matter?
International Nuclear Information System (INIS)
Cohen, T.D.; Washington Univ., Seattle, WA
1995-01-01
The QCD sum rule approach to the properties of hadrons in both the vacuum and in nuclear matter is discussed. The primary limitation for the nuclear matter case is the absence of reliable phenomenological information about the form of the spectral function and about the value of certain four quark condensates. The approach gives moderate evidence in support of the Dirac phenomenology picture of strong attractive Lorentz scalar and repulsive Lorentz vector optical potentials. The approach gives weak evidence for decreasing vector meson masses in medium. (orig.)
Sum rules and exclusive processes in quantum chromodynamics
International Nuclear Information System (INIS)
Radyushkin, A.V.
1983-01-01
A brief review of results of analyzing hadron form factors is presented. The analysis of hardron form factors was conducted by the method of QCD sum rules. The method is based on the concept of quark-hadron duality. Correlation of calculation results with available experimental data was performed. The conclusion is made that it is sufficient to consider only the contribution of the simplest diagrams which don't contain gluon exchanges in order to describe experimental data on pion, proton and neutron form factors
Energy-weighted sum rules for mesons in hot and dense matter
Cabrera, D.; Polls, A.; Ramos, A.; Tolos Rigueiro, Laura
2009-01-01
We study energy-weighted sum rules of the pion and kaon propagator in nuclear matter at finite temperature. The sum rules are obtained from matching the Dyson form of the meson propagator with its spectral Lehmann representation at low and high energies. We calculate the sum rules for specific
Sum rules for baryonic vertex functions and the proton wave function in QCD
International Nuclear Information System (INIS)
Lavelle, M.J.
1985-01-01
We consider light-cone sum rules for vertex functions involving baryon-meson couplings. These sum rules relate the non-perturbative, and experimentally known, coupling constants to the moments of the wave function of the proton state. Our results for these moments are consistent with those obtained from QCD sum rules for two-point functions. (orig.)
Spin Sum Rules and Polarizabilities: Results from Jefferson Lab
International Nuclear Information System (INIS)
Jian-Ping Chen
2006-01-01
The nucleon spin structure has been an active, exciting and intriguing subject of interest for the last three decades. Recent experimental data on nucleon spin structure at low to intermediate momentum transfers provide new information in the confinement regime and the transition region from the confinement regime to the asymptotic freedom regime. New insight is gained by exploring moments of spin structure functions and their corresponding sum rules (i.e. the generalized Gerasimov-Drell-Hearn, Burkhardt-Cottingham and Bjorken). The Burkhardt-Cottingham sum rule is verified to good accuracy. The spin structure moments data are compared with Chiral Perturbation Theory calculations at low momentum transfers. It is found that chiral perturbation calculations agree reasonably well with the first moment of the spin structure function g 1 at momentum transfer of 0.05 to 0.1 GeV 2 but fail to reproduce the neutron data in the case of the generalized polarizability (delta) LT (the (delta) LT puzzle). New data have been taken on the neutron ( 3 He), the proton and the deuteron at very low Q 2 down to 0.02 GeV 2 . They will provide benchmark tests of Chiral dynamics in the kinematic region where the Chiral Perturbation theory is expected to work
Borel sum rules for octet baryons in nuclear medium
International Nuclear Information System (INIS)
Kondo, Y.; Morimatsu, O.
1992-06-01
Borel sum rules are examined for octet baryons in the nuclear medium. First, it is noticed that in the medium the dispersion relation is realized for the retarded correlation Π R (ω, q 2 ) in the energy ω. Then, Π R (ω, q 2 ) is split into even and odd parts of ω in order to apply the Borel transformation. The obtained Borel sum rules differ from those of previous works. The mass shifts of octet baryons are calculated in the leading order of the operator product expansion with linear density approximation for the condensates. It is found that both scalar and vector condensates of the quark field, and + q>, induce attraction to the octet baryons in the medium in contrast to the results of previous works. It is also found that |δM N | > |δM Λ | > |δM Σ | ∼ |δM Ξ |. The absolute values, however, turn out to be one order of magnitude larger than those empirically known if a Borel mass of around 1 GeV is used in the present approximation. (author)
Bottom mass from nonrelativistic sum rules at NNLL
Energy Technology Data Exchange (ETDEWEB)
Stahlhofen, Maximilian
2013-01-15
We report on a recent determination of the bottom quark mass from nonrelativistic (large-n) {Upsilon} sum rules with renormalization group improvement (RGI) at next-to-next-to-leading logarithmic (NNLL) order. The comparison to previous fixed-order analyses shows that the RGI computed in the vNRQCD framework leads to a substantial stabilization of the theoretical sum rule moments with respect to scale variations. A single moment fit (n=10) to the available experimental data yields M{sub b}{sup 1S}=4.755{+-}0.057{sub pert}{+-}0.009{sub {alpha}{sub s}}{+-}0.003{sub exp} GeV for the bottom 1S mass and anti m{sub b}(anti m{sub b})=4.235{+-}0.055{sub pert}{+-}0.003{sub exp} GeV for the bottom MS mass. The quoted uncertainties refer to the perturbative error and the uncertainties associated with the strong coupling and the experimental input.
Renormalized sum rules for structure functions of heavy meson decays
International Nuclear Information System (INIS)
Grozin, A.G.; Korchemsky, G.P.
1996-01-01
We consider the properties of the structure functions of inclusive heavy meson decays B→X c and treat the c quark mass as a free parameter. We show that in two extreme cases of heavy and light c quarks the structure functions of heavy-heavy and heavy-light transitions are given by a Fourier transform of the matrix elements of Wilson lines containing a timelike and a lightlike segment, correspondingly. Using the renormalization properties of Wilson lines we find the dependence of the structure functions on the factorization scale, the structure function of the heavy-heavy transition is renormalized multiplicatively, while that of the heavy-light transition obeys the GLAP-type evolution equation. We propose a generalization of the sum rules for the moments of the structure functions (Bjorken, Voloshin, and the open-quote open-quote third close-quote close-quote sum rules) with a soft exponential factorization cutoff, which correctly incorporates both perturbative and nonperturbative effects. We analyze nonperturbative corrections by first considering infrared renormalon contributions to the Wilson lines. Uncertainties induced by the leading renormalon pole at u=1/2 are exactly canceled by a similar uncertainty in the heavy quark pole mass. The leading nonperturbative corrections associated with the next renormalon at u=1 are parametrized by the matrix element μ π 2 which is proportional to the heavy quark kinetic energy. copyright 1996 The American Physical Society
Spectral sum rules and search for periodicities in DNA sequences
International Nuclear Information System (INIS)
Chechetkin, V.R.
2011-01-01
Periodic patterns play the important regulatory and structural roles in genomic DNA sequences. Commonly, the underlying periodicities should be understood in a broad statistical sense, since the corresponding periodic patterns have been strongly distorted by the random point mutations and insertions/deletions during molecular evolution. The latent periodicities in DNA sequences can be efficiently displayed by Fourier transform. The criteria of significance for observed periodicities are obtained via the comparison versus the counterpart characteristics of the reference random sequences. We show that the restrictions imposed on the significance criteria by the rigorous spectral sum rules can be rationally described with De Finetti distribution. This distribution provides the convenient intermediate asymptotic form between Rayleigh distribution and exact combinatoric theory. - Highlights: → We study the significance criteria for latent periodicities in DNA sequences. → The constraints imposed by sum rules can be described with De Finetti distribution. → It is intermediate between Rayleigh distribution and exact combinatoric theory. → Theory is applicable to the study of correlations between different periodicities. → The approach can be generalized to the arbitrary discrete Fourier transform.
A probabilistic approach of sum rules for heat polynomials
International Nuclear Information System (INIS)
Vignat, C; Lévêque, O
2012-01-01
In this paper, we show that the sum rules for generalized Hermite polynomials derived by Daboul and Mizrahi (2005 J. Phys. A: Math. Gen. http://dx.doi.org/10.1088/0305-4470/38/2/010) and by Graczyk and Nowak (2004 C. R. Acad. Sci., Ser. 1 338 849) can be interpreted and easily recovered using a probabilistic moment representation of these polynomials. The covariance property of the raising operator of the harmonic oscillator, which is at the origin of the identities proved in Daboul and Mizrahi and the dimension reduction effect expressed in the main result of Graczyk and Nowak are both interpreted in terms of the rotational invariance of the Gaussian distributions. As an application of these results, we uncover a probabilistic moment interpretation of two classical integrals of the Wigner function that involve the associated Laguerre polynomials. (paper)
Origin of the violation of the Gottfried sum rule
International Nuclear Information System (INIS)
Hwang, W.P.; Speth, J.
1992-01-01
Using generalized Sullivan processes to generate sea-quark distributions of a nucleon at Q 2 =4 GeV 2 , we find that the recent finding by the New Muon Collaboration on the violation of the Gottfried sum rule can be understood quantitatively, including the shape of F 2 p (x)-F 2 n (x) as a function of x. The agreement may be seen as a clear evidence toward the validity of a recent suggestion of Hwang, Speth, and Brown that the sea distributions of a hadron, at low and moderate Q 2 (at least up to a few GeV 2 ), may be attributed primarily to generalized Sullivan processes
Isovector giant monopole resonances: A sum-rule approach
International Nuclear Information System (INIS)
Goeke, K.; Bonn Univ.; Castel, B.
1980-01-01
Several useful sum rules associated with isovector giant monopole resonances are calculated for doubly closed shell nuclei. The calculation is based on techniques known from constrained and adiabatic time-dependent Hartree-Fock theories and assume various Skyrme interactions. The results obtained form, together with the compiled literature, the basis for a quantitative description of the RPA strength distribution in terms of energy-weighted moments. These, together with strength distribution properties, are determined by a hierarchy of determinantal relations between moments. The isovector giant monopole resonance turns out to be a rather broad resonance centered at E = 46 Asup(-1/10) MeV with an extended width of more than 16 MeV. The consequences regarding isospin impurities in the nuclear ground state are discussed. (orig.)
Scalar Hidden-Charm Tetraquark States with QCD Sum Rules
Di, Zun-Yan; Wang, Zhi-Gang; Zhang, Jun-Xia; Yu, Guo-Liang
2018-02-01
In this article, we study the masses and pole residues of the pseudoscalar-diquark-pseudoscalar-antidiquark type and vector-diquark-vector-antidiquark type scalar hidden-charm cu\\bar{c}\\bar{d} (cu\\bar{c}\\bar{s}) tetraquark states with QCD sum rules by taking into account the contributions of the vacuum condensates up to dimension-10 in the operator product expansion. The predicted masses can be confronted with the experimental data in the future. Possible decays of those tetraquark states are also discussed. Supported by the National Natural Science Foundation of China under Grant No. 11375063, the Fundamental Research Funds for the Central Universities under Grant Nos. 2016MS155 and 2016MS133
Thermal Properties of Light Tensor Mesons via QCD Sum Rules
Directory of Open Access Journals (Sweden)
K. Azizi
2015-01-01
Full Text Available The thermal properties of f2(1270, a2(1320, and K2*(1430 light tensor mesons are investigated in the framework of QCD sum rules at finite temperature. In particular, the masses and decay constants of the light tensor mesons are calculated taking into account the new operators appearing at finite temperature. The numerical results show that, at the point at which the temperature-dependent continuum threshold vanishes, the decay constants decrease with amount of (70–85% compared to their vacuum values, while the masses diminish about (60–72% depending on the kinds of the mesons under consideration. The results obtained at zero temperature are in good consistency with the experimental data as well as the existing theoretical predictions.
Sum rules and systematics for baryon magnetic moments
International Nuclear Information System (INIS)
Lipkin, H.J.
1983-11-01
The new experimental values of hyperon magnetic moments are compared with sum rules predicted from general quark models. Three difficulties encountered are not easily explained by simple models. The isovector contributions of nonstrange quarks to hyperon moments are smaller than the corresponding contribution to nucleon moments, indicating either appreciable configuration mixing in hyperon wave functions and absent in nucleons or an additional isovector contribution beyond that of valence quarks; e.g. from a pion cloud. The large magnitude of the THETA - moment may indicate that the strange quark contribution to the THETA moments is considerably larger than the value μ(Λ) predicted by simple models which have otherwise been very successful. The set of controversial values from different experiments of the Σ - moment include a value very close to -(1/2)μ(Σ + ) which would indicate that strange quarks do not contribute at all to the Σ moments. (author)
Sum rules and systematics for baryon magnetic moments
International Nuclear Information System (INIS)
Lipkin, H.J.
1984-01-01
The new experimental values of hyperon magnetic moments are compared with sum rules predicted from general quark models. Three difficulties encountered are not easily explained by simple models. The isovector contributions of nonstrange quarks to hyperon moments are smaller than the corresponding contribution to nucleon moments, indicating either appreciable configuration mixing in hyperon wave functions and absent in nucleons or an additional isovector contribution beyond that of valence quarks, e.g. from a pion cloud. The large magnitude of the Ψ - moment may indicate that the strange quark contribution to the Ψ moments is considerably larger than the value μ(Λ) predicted by simple models which have otherwise been very successful. The set of controversial values from different experiments of the Σ - moment include a value very close to -1/2μ(Σ + ) which would indicate that strange quarks do not contribute at all to the Σ moments. (orig.)
A sum rule approach to the violation of Dashen's theorem
International Nuclear Information System (INIS)
Moussallam, B.
1999-01-01
A classic sum rule by Das et al. is extended to seven of the low-energy constant K i , introduced by Urech, which parameterizes electromagnetic corrections at chiral order O(e 2 p 2 ). Using the spurion formalism, a simple convolution representation is shown to hold and the structure in terms of the chiral renormalization scale, QCD renormalization scale and the QED gauge parameter is displayed. The role of the resonances is studied as providing rational interpolants to relevant QCD n-point functions in the Euclidean domain. A variety of asymptotic constraints must be implemented which have phenomenological consequences. A current assumption concerning the dominance of the lowest-lying resonances is shown clearly to fail in some cases. (author)
Splitting of electrons and violation of the Luttinger sum rule
Quinn, Eoin
2018-03-01
We obtain a controlled description of a strongly correlated regime of electronic behavior. We begin by arguing that there are two ways to characterize the electronic degree of freedom, either by the canonical fermion algebra or the graded Lie algebra su (2 |2 ) . The first underlies the Fermi liquid description of correlated matter, and we identify a regime governed by the latter. We exploit an exceptional central extension of su (2 |2 ) to employ a perturbative scheme recently developed by Shastry and obtain a series of successive approximations for the electronic Green's function. We then focus on the leading approximation, which reveals a splitting in two of the electronic dispersion. The Luttinger sum rule is violated, and a Mott metal-insulator transition is exhibited. We offer a perspective.
The DHG sum rule measured with medium energy photons
International Nuclear Information System (INIS)
Hicks, K.; Ardashev, K.; Babusci, D.
1997-01-01
The structure of the nucleon has many important features that are yet to be uncovered. Of current interest is the nucleon spin-structure which can be measured by doing double-polarization experiments with photon beams of medium energies (0.1 to 2 GeV). One such experiment uses dispersion relations, applied to the Compton scattering amplitude, to relate measurement of the total reaction cross section integrated over the incident photon energy to the nucleon anomalous magnetic moment. At present, no single facility spans the entire range of photon energies necessary to test this sum rule. The Laser-Electron Gamma Source (LEGS) facility will measure the double-polarization observables at photon energies between 0.15--0.47 MeV. Either the SPring8 facility, the GRAAL facility (France), or Jefferson Laboratory could make similar measurements at higher photon energies. A high-precision measurement of the spin-polarizability and the Drell-Hearn-Gerasimov sum rule is now possible with the advent of high-polarization solid HD targets at medium energy polarized photon facilities such as LEGS, GRAAL and SPring8. Other facilities with lower polarization in either the photon beam or target (or both) are also pursuing these measurements because of the high priority associated with this physics. The Spin-asymmetry (SASY) detector that will be used at LEGS has been briefly outlined in this paper. The detector efficiencies have been explored with simulations studies using the GEANT software, with the result that both charged and uncharged pions can be detected with a reasonable efficiency (> 30%) over a large solid angle. Tracking with a TPC, which will be built at LEGS over the next few years, will improve the capabilities of these measurements
Impact of Duality Violations on Spectral Sum Rule analyses
International Nuclear Information System (INIS)
Cata, Oscar
2007-01-01
Recent sum rule analyses on the two-point correlator have led to significant discrepancies in the values found for the OPE condensates, most dramatically in the dimension eight condensate and to a lesser extent in the dimension six one [R. Barate et al., ALEPH Collaboration, Eur. Phys. J. C 4 (1998) 409; K. Ackerstaff et al., OPAL Collaboration, Eur. Phys. J. C 7 (1999) 571, (arXiv:hep-ex/9808019); S. Peris, B. Phily and E. de Rafael, Phys. Rev. Lett. 86 (2001) 14, (arXiv:hep-ph/0007338); S. Friot, D. Greynat and E. de Rafael, JHEP 0410 (2004) 043, (arXiv:hep-ph/0408281); M. Davier, L. Girlanda, A. Hocker and J. Stern, Phys. Rev. D 58 (1998) 096014, (arXiv:hep-ph/9802447); B.L. Ioffe and K.N. Zyablyuk, Nucl. Phys. A 687 (2001) 437, (arXiv:hep-ph/0010089). K.N. Zyablyuk, Eur. Phys. J. C 38 (2004) 215, (arXiv:hep-ph/0404230); J. Bijnens, E. Gamiz and J. Prades, JHEP 0110 (2001) 009, (arXiv:hep-ph/0108240); C.A. Dominguez and K. Schilcher, Phys. Lett. B 581 (2004) 193, (arXiv:hep-ph/0309285); J. Rojo and J. I. Latorre, JHEP 0401 (2004) 055, (arXiv:hep-ph/0401047); V. Cirigliano, E. Golowich and K. Maltman, Phys. Rev. D 68 (2003) 054013, (arXiv:hep-ph/0305118); S. Ciulli, C. Sebu, K. Schilcher and H. Spiesberger, Phys. Lett. B 595 (2004) 359, (arXiv:hep-ph/0312212). S. Narison, (arXiv:hep-ph/0412152)]. Precise knowledge of these condensates is of relevance in kaon decays [M. Knecht, S. Peris and E. de Rafael, Phys. Lett. B 457 (1999) 227, (arXiv:hep-ph/9812471); J.F. Donoghue and E. Golowich, Phys. Lett. B 478 (2000) 172, (arXiv:hep-ph/9911309); M. Knecht, S. Peris and E. de Rafael, Phys. Lett. B 508 (2001) 117, (arXiv:hep-ph/0102017)] and therefore it seems mandatory to assess the actual impact of what is commonly neglected in spectral sum rules, most prominently the issue of duality violations. We will explicitly compute them in a toy model and show that they are a priori non-negligible
Quark-spin isospin sum rules and the Adler-Weisberger relation in nuclei
International Nuclear Information System (INIS)
Delorme, J.; Ericson, M.
1982-01-01
We use a quark model to extend the classical Gamow-Teller sum rule for the difference of the β - and β + strengths to excitations of the nucleon (mainly the Δ isobar). A schematic model illustrates the realization of the new sum rule when a particle-hole force is introduced. We discuss the connection of our result with the model-independent Adler-Weisberger sum rule. (orig.)
Symbolic methods for the evaluation of sum rules of Bessel functions
International Nuclear Information System (INIS)
Babusci, D.; Dattoli, G.; Górska, K.; Penson, K. A.
2013-01-01
The use of the umbral formalism allows a significant simplification of the derivation of sum rules involving products of special functions and polynomials. We rederive in this way known sum rules and addition theorems for Bessel functions. Furthermore, we obtain a set of new closed form sum rules involving various special polynomials and Bessel functions. The examples we consider are relevant for applications ranging from plasma physics to quantum optics
Magnetic susceptibility and M1 transitions in /sup 208/Pb. [Sum rules
Energy Technology Data Exchange (ETDEWEB)
Traini, M; Lipparini, E; Orlandini, G; Stringari, S [Dipartimento di Matematica e Fisica, Universita di Trento, Italy
1979-04-16
M1 transitions in /sup 208/Pb are studied by evaluating energy-weighted and inverse energy-weighted sum-rules. The role of the nuclear interaction is widely discussed. It is shown that the nuclear potential increases the energy-weighted sum rule and lowers the inverse energy-weighted sum rule, with respect to the prediction of the pure shell model. Values of strengths and excitation energies are compared with experimental results and other theoretical calculations.
Sum rules for the real parts of nonforward current-particle scattering amplitudes
International Nuclear Information System (INIS)
Abdel-Rahman, A.M.M.
1976-01-01
Extending previous work, using Taha's refined infinite-momentum method, new sum rules for the real parts of nonforward current-particle scattering amplitudes are derived. The sum rules are based on covariance, casuality, scaling, equal-time algebra and unsubtracted dispersion relations for the amplitudes. A comparison with the corresponding light-cone approach is made, and it is shown that the light-cone sum rules would also follow from the assumptions underlying the present work
Gottfried sum rule and mesonic exchanges in deuteron
International Nuclear Information System (INIS)
Kaptari, L.P.
1991-01-01
Recent NMC data on the experimental value of the Gottfried Sum are discussed. It is shown that the Gottfried Sum is sensitive to the nuclear structure corrections, viz. themesonic exchanges and binding effects. A new estimation of the Gottfried Sum is given. The obtained result is close to the quark-parton prediction of 1/3. 11 refs.; 2 figs
Sum rules for nuclear excitations with the Skyrme-Landau interaction
International Nuclear Information System (INIS)
Liu Kehfei; Luo Hongde; Ma Zhongyu; Feng Man; Shen Qingbiao
1991-01-01
The energy-weighted sum rules for electric, magnetic, Fermi and Gamow-Teller transitions with the Skyrme-Landau interaction are derived from the double commutators and numerically calculated in a HF + RPA formalism. As a numerical check of the Thouless theorem, our self-consistent calculations show that the calculated RPA strengths exhaust more than 85% of the sum rules in most cases. The well known non-energy-weighted sum rules for Fermi and Gamow-Teller transitions are also checked numerically. The sum rules are exhausted by more than 94% in these cases. (orig.)
International Nuclear Information System (INIS)
Larin, S.A.; Nationaal Inst. voor Kernfysica en Hoge-Energiefysica; Vermaseren, J.A.M.
1990-01-01
The next-next-to-leading order QCD corrections to the Gross-Llewellyn Smith sum rule for deep inelastic neutrino-nucleon scattering and to the Bjorken sum rule for polarized electron-nucleon scattering have been computed. This involved the proper treatment of γ 5 inside the loop integrals with dimensional regularization. It is found that the difference between the two sum rules are entirely due to a class of 6 three loop graphs and is of the order of 1% of the leading QCD term. Hence the Q 2 behavior of both sum rules should be the same if the physics is described adequately by the lower order terms of perturbative QCD. (author). 12 refs.; 2 figs.; 4 tabs
QCD sum rule study of hidden-charm pentaquarks
Energy Technology Data Exchange (ETDEWEB)
Chen, Hua-Xing; Cui, Er-Liang [Beihang University, School of Physics and Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beijing (China); Chen, Wei; Steele, T.G. [University of Saskatchewan, Department of Physics and Engineering Physics, Saskatoon, Saskatchewan (Canada); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University and Institute of Modern Physics of CAS, Research Center for Hadron and CSR Physics, Lanzhou (China); Zhu, Shi-Lin [Peking University, School of Physics and State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Peking University, Center of High Energy Physics, Beijing (China)
2016-10-15
We study the mass spectra of hidden-charm pentaquarks having spin J = (1)/(2)/(3)/(2)/(5)/(2) and quark contents uudc anti c. We systematically construct all the relevant local hidden-charm pentaquark currents, and we select some of them to perform QCD sum rule analyses. We find that the P{sub c}(4380) and P{sub c}(4450) can be identified as hidden-charm pentaquark states composed of an anti-charmed meson and a charmed baryon. Besides them, we also find (a) the lowest-lying hidden-charm pentaquark state of J{sup P} = 1/2{sup -} has the mass 4.33{sup +0.17}{sub -0.13} GeV, while the one of J{sup P} = 1/2{sup +} is significantly higher, that is, around 4.7-4.9 GeV; (b) the lowest-lying hidden-charm pentaquark state of J{sup P} = 3/2{sup -} has the mass 4.37{sup +0.18}{sub -0.13} GeV, consistent with the P{sub c}(4380) of J{sup P} = 3/2{sup -}, while the one of J{sup P} = 3/2{sup +} is also significantly higher, that is, above 4.6 GeV; (c) the hidden-charm pentaquark state of J{sup P} = 5/2{sup -} has a mass around 4.5-4.6 GeV, slightly larger than the P{sub c}(4450) of J{sup P} = 5/2{sup +}. (orig.)
A self-consistent semiclassical sum rule approach to the average properties of giant resonances
International Nuclear Information System (INIS)
Li Guoqiang; Xu Gongou
1990-01-01
The average energies of isovector giant resonances and the widths of isoscalar giant resonances are evaluated with the help of a self-consistent semiclassical Sum rule approach. The comparison of the present results with the experimental ones justifies the self-consistent semiclassical sum rule approach to the average properties of giant resonances
Radiative E1-decay of charmonium 1P1 level within sum rules of quantum chromodynamics
International Nuclear Information System (INIS)
Martynenko, A.P.
1991-01-01
Analysis of radiative decay of 1 P 1 → 1 S 0 + γ charmonium within sum rules of quantum chromodynamics was conducted. The sum rule, taking account of gluon exponential correction, was obtained, and width of Χ → η c + γ decay was calculated
The Bethe Sum Rule and Basis Set Selection in the Calculation of Generalized Oscillator Strengths
DEFF Research Database (Denmark)
Cabrera-Trujillo, Remigio; Sabin, John R.; Oddershede, Jens
1999-01-01
Fulfillment of the Bethe sum rule may be construed as a measure of basis set quality for atomic and molecular properties involving the generalized oscillator strength distribution. It is first shown that, in the case of a complete basis, the Bethe sum rule is fulfilled exactly in the random phase...
Sum rules and moments for lepton-pair production. [Cross sections, Drell--Yan formula
Energy Technology Data Exchange (ETDEWEB)
Hwa, R.C.
1978-01-01
Sum rules on lepton-pair production cross sections are derived on the bases of the Drell--Yan formula and the known sum rules in leptoproduction. Also exact relations are obtained between the average transverse momenta squared of the valence quarks and moments of the dilepton cross sections. 12 references.
Second-moment sum rules for correlation functions in a classical ionic mixture
Suttorp, L.G.; Ebeling, W.
1992-01-01
The complete set of second-moment sum rules for the correlation functions of arbitrarily high order describing a classical multi-component ionic mixture in equilibrium is derived from the grand-canonical ensemble. The connection of these sum rules with the large-scale behaviour of fluctuations in an
B-decay form factors from QCD sum rules
International Nuclear Information System (INIS)
Offen, Nils
2008-01-01
In the Standard Model of particle physics there is only one source of CP-violation. Namely, a single complex phase in the unitary 3 x 3 CKM-Matrix governing flavor transitions in the weak interaction. The unitarity is usually visualized by a triangle in the complex ρ - η-plane. Therefore testing this framework comes down to measuring weak decays, relating observables to sides and angles of this so called Unitarity Triangle(UT). Particular interest in this respect is payed to decays of mesons containing a heavy b-quark, giving the opportunity to alone determine all parameters of the UT. Doing this is far from easy. Besides tedious experimental measurements the theoretical calculations are plagued by hadronic quantities which cannot be determined by perturbation theory. In this work several of these quantities so called form factors are computed using the well known method of light cone sum rules(LCSR). Two different setups have been used. One, established in this work, utilizing a correlation function with an on-shell B-Meson and one following the traditional calculation by taking the light meson on-shell. Both using light cone expansion in the respective on-shell mesons distribution amplitudes. While the first approach allows to calculate a whole bunch of phenomenologically interesting quantities by just changing Dirac-structures of the relevant currents it has the drawback that it does not have access to the well developed twist expansion of the latter. To incorporate higher Fock-state contributions the first models for three-particle distribution amplitudes of the B-Meson have been derived. α s -corrections remain out of the scope of this work. Nevertheless does a comparison with more sophisticated methods show an encouraging numerical agreement. In the second setup all known corrections especially the never verified α s -corrections to Twist three terms have been recalculated and a competitive result for the CKM-matrixelement vertical stroke V ub vertical
Continuum contributions to dipole oscillator-strength sum rules for hydrogen in finite basis sets
DEFF Research Database (Denmark)
Oddershede, Jens; Ogilvie, John F.; Sauer, Stephan P. A.
2017-01-01
Calculations of the continuum contributions to dipole oscillator sum rules for hydrogen are performed using both exact and basis-set representations of the stick spectra of the continuum wave function. We show that the same results are obtained for the sum rules in both cases, but that the conver......Calculations of the continuum contributions to dipole oscillator sum rules for hydrogen are performed using both exact and basis-set representations of the stick spectra of the continuum wave function. We show that the same results are obtained for the sum rules in both cases......, but that the convergence towards the final results with increasing excitation energies included in the sum over states is slower in the basis-set cases when we use the best basis. We argue also that this conclusion most likely holds also for larger atoms or molecules....
Derivation of sum rules for quark and baryon fields. [light-like charges
Energy Technology Data Exchange (ETDEWEB)
Bongardt, K [Karlsruhe Univ. (TH) (Germany, F.R.). Inst. fuer Theoretische Kernphysik
1978-08-21
In an analogous way to the Weinberg sum rules, two spectral-function sum rules for quark and baryon fields are derived by means of the concept of lightlike charges. The baryon sum rules are valid for the case of SU/sub 3/ as well as for SU/sub 4/ and the one-particle approximation yields a linear mass relation. This relation is not in disagreement with the normal linear GMO formula for the baryons. The calculated masses of the first resonance states agree very well with the experimental data.
The Relation between the Electric Conductance of Nanostructure Bridge and Friedel Sum Rule
International Nuclear Information System (INIS)
Kotani, Y; Shima, N; Makoshi, K
2012-01-01
We analyze the electric conductance through nanostructure bridges in terms of phase-shifts, which satisfy the Friedel sum rule. The phase-shifts are given by solving the eigenvalue equation obtained by extending the method applied to a single impurity problem in a metal. The local charge neutrality condition is introduced through the Friedel sum rule. It is analytically shown that the electric conductance can increase as the two electrodes separate with the condition in which the phase-shifts satisfy the Friedel sum rule. The increment of the distance between two electrodes is obtained by gradually separating interatomic distance.
Renormalization group summation of Laplace QCD sum rules for scalar gluon currents
Directory of Open Access Journals (Sweden)
Farrukh Chishtie
2016-03-01
Full Text Available We employ renormalization group (RG summation techniques to obtain portions of Laplace QCD sum rules for scalar gluon currents beyond the order to which they have been explicitly calculated. The first two of these sum rules are considered in some detail, and it is shown that they have significantly less dependence on the renormalization scale parameter μ2 once the RG summation is used to extend the perturbative results. Using the sum rules, we then compute the bound on the scalar glueball mass and demonstrate that the 3 and 4-Loop perturbative results form lower and upper bounds to their RG summed counterparts. We further demonstrate improved convergence of the RG summed expressions with respect to perturbative results.
Endpoint behavior of the pion distribution amplitude in QCD sum rules with nonlocal condensates
International Nuclear Information System (INIS)
Mikhailov, S. V.; Pimikov, A. V.; Stefanis, N. G.
2010-01-01
Starting from the QCD sum rules with nonlocal condensates for the pion distribution amplitude, we derive another sum rule for its derivative and its ''integral derivatives''--defined in this work. We use this new sum rule to analyze the fine details of the pion distribution amplitude in the endpoint region x∼0. The results for endpoint-suppressed and flattop (or flatlike) pion distribution amplitudes are compared with those we obtained with differential sum rules by employing two different models for the distribution of vacuum-quark virtualities. We determine the range of values of the derivatives of the pion distribution amplitude and show that endpoint-suppressed distribution amplitudes lie within this range, while those with endpoint enhancement--flat-type or Chernyak-Zhitnitsky like--yield values outside this range.
Forward Compton scattering with weak neutral current: Constraints from sum rules
Directory of Open Access Journals (Sweden)
Mikhail Gorchtein
2015-07-01
Full Text Available We generalize forward real Compton amplitude to the case of the interference of the electromagnetic and weak neutral current, formulate a low-energy theorem, relate the new amplitudes to the interference structure functions and obtain a new set of sum rules. We address a possible new sum rule that relates the product of the axial charge and magnetic moment of the nucleon to the 0th moment of the structure function g5(ν,0. For the dispersive γZ-box correction to the proton's weak charge, the application of the GDH sum rule allows us to reduce the uncertainty due to resonance contributions by a factor of two. The finite energy sum rule helps addressing the uncertainty in that calculation due to possible duality violations.
Calculation of baryon sum rules and SU(4) mass formulae for mesons and baryons
International Nuclear Information System (INIS)
Bongardt, K.
1976-01-01
Light cone coordinates and field-field anticommutators for the free quark model on the light cone are introduced and light cone charges and light cone currents for the free quark model as well as sum rules for the meson and quark states are derived. The derivation of sum rules for the baryons is attempted. It is seen that it is possible formally to derive the same sum rules for the baryons and for the quarks. The baryon sums were derived through the symmetry properties of the baryon fields. Explicit assumptions about the spatial distribution of the three quarks in the baryons were not utilized. The meson-baryon Σ-terms, Zweig's rules in the SU (4) and a number of properties of the M-matrix are discussed. (BJ) [de
Lorentz-Lorenz quenching for the Gamow-Teller sum rule
International Nuclear Information System (INIS)
Delorme, J.; Ericson, M.; Figureau, A.
1984-03-01
We investigate the modification of the Gamow-Teller sum rule brought in by nucleonic excitations. The general trend of the data is well reproduced. The value of the force which mixes nucleonic and nuclear excitations is discussed
General solution of superconvergent sum rules for scattering of I=1 reggeons on baryons
International Nuclear Information System (INIS)
Grigoryan, A.A.; Khachatryan, G.N.
1986-01-01
Superconvergent sum rules for reggeon-particle scattering are applied to scattering of reggeons α i (i=π, ρ, A 2 ) with isospin I=1 on baryons with strangeness S=-1. The saturation scheme of these sum rules is determined on the basis of experimental data. Two series of baryon resonances with arbitrary isospins I and spins J=I+1/2 and J=I-1/2 are predicted. A general solution for vertices of interaction of these resonances with α i is found. Predictions for coupling vertices B α i B'(B, B'=Λ, Σ, Σ * ) agree well with the experiment. It is shown that the condition of sum rules saturation by minimal number of resonances brings to saturation schemes resulting from experimental data. A general solution of sum rules for scattering of α i reggeons on Ξ and Ω hyperons is analyzed
Complex-energy approach to sum rules within nuclear density functional theory
Hinohara, Nobuo; Kortelainen, Markus; Nazarewicz, Witold; Olsen, Erik
2015-04-01
Background: The linear response of the nucleus to an external field contains unique information about the effective interaction, the correlations governing the behavior of the many-body system, and the properties of its excited states. To characterize the response, it is useful to use its energy-weighted moments, or sum rules. By comparing computed sum rules with experimental values, the information content of the response can be utilized in the optimization process of the nuclear Hamiltonian or the nuclear energy density functional (EDF). But the additional information comes at a price: compared to the ground state, computation of excited states is more demanding. Purpose: To establish an efficient framework to compute energy-weighted sum rules of the response that is adaptable to the optimization of the nuclear EDF and large-scale surveys of collective strength, we have developed a new technique within the complex-energy finite-amplitude method (FAM) based on the quasiparticle random-phase approximation (QRPA). Methods: To compute sum rules, we carry out contour integration of the response function in the complex-energy plane. We benchmark our results against the conventional matrix formulation of the QRPA theory, the Thouless theorem for the energy-weighted sum rule, and the dielectric theorem for the inverse-energy-weighted sum rule. Results: We derive the sum-rule expressions from the contour integration of the complex-energy FAM. We demonstrate that calculated sum-rule values agree with those obtained from the matrix formulation of the QRPA. We also discuss the applicability of both the Thouless theorem about the energy-weighted sum rule and the dielectric theorem for the inverse-energy-weighted sum rule to nuclear density functional theory in cases when the EDF is not based on a Hamiltonian. Conclusions: The proposed sum-rule technique based on the complex-energy FAM is a tool of choice when optimizing effective interactions or energy functionals. The method
Confinement Can Violate Momentum Sum Rule in QCD at High Energy Colliders
Nayak, Gouranga C
2018-01-01
Momentum sum rule in QCD is widely used at high energy colliders. Although the exact form of the confinement potential energy is not known but the confinement potential energy at large distance $r$ can not rise slower than ${\\rm ln}(r)$. In this paper we find that if the confinement potential energy at large distance $r$ rises linearly with $r$ (or faster) then the momentum sum rule in QCD is violated at the high energy colliders.
Sum rules for elements of flavor-mixing matrices based on a non-semisimple symmetry
International Nuclear Information System (INIS)
Sogami, Ikuo S.
2006-01-01
Sum rules for elements of flavor-mixing matrices (FMMs) are derived within a new algebraic theory for flavor physics, in which the FMMs are identified with elements of the Lie group isomorphic to SU(2) x U(1). The resulting sum rules originating from the unique elaborate structure of the algebra of the group are so simple and explicit that their validity can be confirmed by analyzing properly processed experimental data. (author)
What can we learn from sum rules for vertex functions in QCD
International Nuclear Information System (INIS)
Craigie, N.S.; Stern, J.
1982-04-01
We demonstrate that the light cone sum rules for vertex functions based on the operator product expansion and QCD perturbation theory lead to interesting relationships between various non-perturbative parameters associated with hadronic bound states (e.g. vertex couplings and decay constants). We also show that such sum rules provide a valuable means of estimating the matrix elements of the higher spin operators in the meson wave function. (author)
Sum Rules of Charm CP Asymmetries beyond the SU(3)_{F} Limit.
Müller, Sarah; Nierste, Ulrich; Schacht, Stefan
2015-12-18
We find new sum rules between direct CP asymmetries in D meson decays with coefficients that can be determined from a global fit to branching ratio data. Our sum rules eliminate the penguin topologies P and PA, which cannot be determined from branching ratios. In this way, we can make predictions about direct CP asymmetries in the standard model without ad hoc assumptions on the sizes of penguin diagrams. We consistently include first-order SU(3)_{F} breaking in the topological amplitudes extracted from the branching ratios. By confronting our sum rules with future precise data from LHCb and Belle II, one will identify or constrain new-physics contributions to P or PA. The first sum rule correlates the CP asymmetries a_{CP}^{dir} in D^{0}→K^{+}K^{-}, D^{0}→π^{+}π^{-}, and D^{0}→π^{0}π^{0}. We study the region of the a_{CP}^{dir}(D^{0}→π^{+}π^{-})-a_{CP}^{dir}(D^{0}→π^{0}π^{0}) plane allowed by current data and find that our sum rule excludes more than half of the allowed region at 95% C.L. Our second sum rule correlates the direct CP asymmetries in D^{+}→K[over ¯]^{0}K^{+}, D_{s}^{+}→K^{0}π^{+}, and D_{s}^{+}→K^{+}π^{0}.
New QCD sum rules for nucleon axial-vector coupling constants
International Nuclear Information System (INIS)
Lee, F.X.; Leinweber, D.B.; Jin, X.
1997-01-01
Two new sets of QCD sum rules for the nucleon axial-vector coupling constants are derived using the external-field technique and generalized interpolating fields. An in-depth study of the predicative ability of these sum rules is carried out using a Monte Carlo based uncertainty analysis. The results show that the standard implementation of the QCD sum rule method has only marginal predicative power for the nucleon axial-vector coupling constants, as the relative errors are large. The errors range from approximately 50% to 100% compared to the nucleon mass obtained from the same method, which has only a 10%- 25% error. The origin of the large errors is examined. Previous analyses of these coupling constants are based on sum rules that have poor operator product expansion convergence and large continuum contributions. Preferred sum rules are identified and their predictions are obtained. We also investigate the new sum rules with an alternative treatment of the problematic transitions which are not exponentially suppressed in the standard treatment. The alternative treatment provides exponential suppression of their contributions relative to the ground state. Implications for other nucleon current matrix elements are also discussed. copyright 1997 The American Physical Society
Slave-particle quantization and sum rules in the t-J model
International Nuclear Information System (INIS)
Le Guillou, J.C.; Ragoucy, E.
1994-12-01
In the framework of constrained systems, the classical Hamiltonian formulation of slave-particle models and their correct quantization are given. The electron-momentum distribution function in the t-J and Hubbard models is then studied in the framework of slave-particle approaches and within the decoupling scheme. It is shown that criticisms which have been addressed in this context coming from a violation of the sum rule for the physical electron are not valid. Due to the correct quantization rules for the slave-particles, the sum rule for the physical electron is indeed obeyed, both exactly and within the decoupling scheme. (author). 15 refs
Sum rules for the spontaneous chiral symmetry breaking parameters of QCD
International Nuclear Information System (INIS)
Craigie, N.S.; Stern, J.
1981-03-01
We discuss in the spirit of the work of Shifman, Vainshtein and Zakharov (SVZ), sum rules involving current-current vacuum correlation functions, whose Wilson expansion starts off with the operators anti qq or (anti qq) 2 , and thus provide information about the chiral symmetry breaking parameters of QCD. We point out that under the type of crude approximations made by SVZ, a value of sub(vac) (250MeV) 3 is obtained from one of these sum rules, in agreement with current expectations. Further we show that a Borel transformed version of the Weinberg sum rule, for VV - AA, current products seem only to make sense for an A 1 mass close to 1.3GeV and it makes little sense with the current algebra mass Msub(A)=anti 2M. We also give an estimate for the chiral symmetry breaking parameters μ 1 6 =2 2 (anti qsub(L) lambda sup(a)γsub(μ)qsub(L))(anti qsub(R) lambdasup(a) γsup(μ)qsub(R)) >sub(vac) entering in the Weinberg sum rules and μ 2 6 =g 2 sub(vac) entering in a new sum rule we propose involving antisymmetric tensor currents J=anti q σsub(μnu) q. (author)
QCD and power corrections to sum rules in deep-inelastic lepton-nucleon scattering
International Nuclear Information System (INIS)
Ravindran, V.; Neerven, W.L. van
2001-01-01
In this paper we study QCD and power corrections to sum rules which show up in deep-inelastic lepton-hadron scattering. Furthermore we will make a distinction between fundamental sum rules which can be derived from quantum field theory and those which are of a phenomenological origin. Using current algebra techniques the fundamental sum rules can be expressed into expectation values of (partially) conserved (axial-)vector currents sandwiched between hadronic states. These expectation values yield the quantum numbers of the corresponding hadron which are determined by the underlying flavour group SU(n) F . In this case one can show that there exist an intimate relation between the appearance of power and QCD corrections. The above features do not hold for phenomenological sum rules, hereafter called non-fundamental. They have no foundation in quantum field theory and they mostly depend on certain assumptions made for the structure functions like super-convergence relations or the parton model. Therefore only the fundamental sum rules provide us with a stringent test of QCD
Lindhard's polarization parameter and atomic sum rules in the local plasma approximation
DEFF Research Database (Denmark)
Cabrera-Trujillo, R.; Apell, P.; Oddershede, J.
2017-01-01
In this work, we analyze the effects of Lindhard polarization parameter, χ, on the sum rule, Sp, within the local plasma approximation (LPA) as well as on the logarithmic sum rule Lp = dSp/dp, in both cases for the system in an initial excited state. We show results for a hydrogenic atom with nuc......In this work, we analyze the effects of Lindhard polarization parameter, χ, on the sum rule, Sp, within the local plasma approximation (LPA) as well as on the logarithmic sum rule Lp = dSp/dp, in both cases for the system in an initial excited state. We show results for a hydrogenic atom...... in terms of a screened charge Z* for the ground state. Our study shows that by increasing χ, the sum rule for p0 it increases, and the value p=0 provides the normalization/closure relation which remains fixed to the number of electrons for the same initial state. When p is fixed...
Sum rules, asymptotic behaviour and (multi)baryon states in the Skyrme model
International Nuclear Information System (INIS)
Mignaco, J.A.; Wulck, S.
1990-01-01
We obtain sum roles that should be satisfied by the solutions of the Euler-Lagrange equation for the chiral angle in the Skyrme model in the hedgehog representation. The sum rules allow to determine the existence of solutions with integer baryon number for well determined values of a relevant dimensionless parameter Φ only. For all other values, there are no solutions with integer baryon number, in particular for the pure non-linear sigma model. (author)
O(N) symmetries, sum rules for generalized Hermite polynomials and squeezed states
International Nuclear Information System (INIS)
Daboul, Jamil; Mizrahi, Salomon S
2005-01-01
Quantum optics has been dealing with coherent states, squeezed states and many other non-classical states. The associated mathematical framework makes use of special functions as Hermite polynomials, Laguerre polynomials and others. In this connection we here present some formal results that follow directly from the group O(N) of complex transformations. Motivated by the squeezed states structure, we introduce the generalized Hermite polynomials (GHP), which include as particular cases, the Hermite polynomials as well as the heat polynomials. Using generalized raising operators, we derive new sum rules for the GHP, which are covariant under O(N) transformations. The GHP and the associated sum rules become useful for evaluating Wigner functions in a straightforward manner. As a byproduct, we use one of these sum rules, on the operator level, to obtain raising and lowering operators for the Laguerre polynomials and show that they generate an sl(2, R) ≅ su(1, 1) algebra
Charmonium spectrum at finite temperature from a Bayesian analysis of QCD sum rules
Directory of Open Access Journals (Sweden)
Morita Kenji
2012-02-01
Full Text Available Making use of a recently developed method of analyzing QCD sum rules, we investigate charmonium spectral functions at finite temperature. This method employs the Maximum Entropy Method, which makes it possible to directly obtain the spectral function from the sum rules, without having to introduce any strong assumption about its functional form. Finite temperature effects are incorporated into the sum rules by the change of the various gluonic condensates that appear in the operator product expansion. These changes depend on the energy density and pressure at finite temperature, which are extracted from lattice QCD. As a result, J/ψ and ηc dissolve into the continuum already at temperatures around 1.0 ~ 1.1 Tc.
Sum rules for four-spinon dynamic structure factor in XXX model
International Nuclear Information System (INIS)
Si Lakhal, B.; Abada, A.
2005-01-01
In the context of the antiferromagnetic spin 12 Heisenberg quantum spin chain (XXX model), we estimate the contribution of the exact four-spinon dynamic structure factor S 4 by calculating a number of sum rules the total dynamic structure factor S is known to satisfy exactly. These sum rules are: the static susceptibility, the integrated intensity, the total integrated intensity, the first frequency moment and the nearest-neighbor correlation function. We find that the contribution of S 4 is between 1% and 2.5%, depending on the sum rule, whereas the contribution of the exact two-spinon dynamic structure factor S 2 is between 70% and 75%. The calculations are numerical and Monte Carlo based. Good statistics are obtained
The calculation of the quark distribution amplitudes of decuplet baryons by means of QCD sum rules
International Nuclear Information System (INIS)
Bonekamp, J.
1994-11-01
Using the QCD sum rule technique, we derive the quark distribution amplitudes of the decuplet memebers Δ(1232), Σ * (1385), Ξ * (1530) and Ω(1672). Generalizing the treatment of the Bethe-Salpeter amplitude, we can distinguish spin- and orbital- angular momentum parts of the quark distributions and establish separate sum rules for the contributions. Projecting out the angular momentum 1/2 contributions, we obtain sum rules which are saturated by the lowest resonance in the given iso spin channel, thus resolving deficiencies of the standard approach. We find that for helicity 1/2 the spin part of the quark distributions is asymmetric. Also the orbital angular momentum contributions are extremely asymmetric and tend to decrease the asymmetry of the spin part. As a result of SU(3) symmetry breaking, configuration mixing occurs and the decuplet baryons Σ * and Ξ * receive octet contributions. The antisymmetric part of these octet contributions is calculated. (orig.)
Sum rule approach to the nuclear response in the isovector spin channel
International Nuclear Information System (INIS)
Alberico, W.M.; Ericson, M.; Molinari, A.
1982-01-01
We study the global features of the response of infinite nuclear matter in the spin-isospin channel through the energy weighted sum rules S 1 and Ssub(-) 1 . In particular we compare the outcome of the ring approximation with the exact RPA evaluation of the sum rules. We also investigate the influence of the collective character of the response, induced by the particle hole force for a longitudinal and transverse spin couplings. We show that S 1 is insensitive to the collectivity of the response, as long as the Δ degree of freedom is ignored. The inverse energy weighted sum rule on the other hand, which is linked to the paramagnetic susceptibility, always reflects the hardening or softening of the nuclear response, due to the repulsive or attractive character of the p-h force. This quantity is well suited to the comparison with the experiments, which we perform for 12 C and 56 Fe. (orig.)
Experimental check of the GDH sum rule at MAMI and ELSA
International Nuclear Information System (INIS)
Krimmer, J.
2002-01-01
The experimental check of the GDH sum rule is being performed at the tagged photon facilities of the electron accelerators MAMI (Mainz) and ELSA (Bonn), using circularly polarized photons impinging on a longitudinally polarized proton target, together with detector systems covering almost the whole solid angle range. Results from the MAMI experiment for the double polarized total photoabsorption cross section in the low energy region (200 MeV < Eγ < 800 MeV) will be shown together with their contribution to the GDH sum rule. Furthermore first results from the ELSA experiment in the higher energy region (680 MeV < Eγ < 1900 MeV) will be presented
The heat current density correlation function: sum rules and thermal conductivity
International Nuclear Information System (INIS)
Singh, Shaminder; Tankeshwar, K; Pathak, K N; Ranganathan, S
2006-01-01
Expressions for the second and fourth sum rules of the heat current density correlation function have been derived in an appropriate ensemble. The thermal conductivity of Lennard-Jones fluids has been calculated using these sum rules for the heat current density correlation function and the Gaussian form of the memory function. It is found that the results obtained for the thermal conductivity are in good agreement with the molecular dynamics simulation results over a wide range of densities and temperatures. Earlier results obtained using the energy current density correlation function are also discussed
The heat current density correlation function: sum rules and thermal conductivity
Energy Technology Data Exchange (ETDEWEB)
Singh, Shaminder [Department of Physics, Panjab University, Chandigarh-160 014 (India); Tankeshwar, K [Department of Physics, Panjab University, Chandigarh-160 014 (India); Pathak, K N [Department of Physics, Panjab University, Chandigarh-160 014 (India); Ranganathan, S [Department of Physics, Royal Military College, Kingston, ON, K7K 7B4 (Canada)
2006-02-01
Expressions for the second and fourth sum rules of the heat current density correlation function have been derived in an appropriate ensemble. The thermal conductivity of Lennard-Jones fluids has been calculated using these sum rules for the heat current density correlation function and the Gaussian form of the memory function. It is found that the results obtained for the thermal conductivity are in good agreement with the molecular dynamics simulation results over a wide range of densities and temperatures. Earlier results obtained using the energy current density correlation function are also discussed.
Bulk stress auto-correlation function in simple liquids-sum rules
International Nuclear Information System (INIS)
Tankeshwar, K.; Bhandari, R.; Pathak, K.N.
1990-10-01
Expressions for the zeroth, second and fourth frequency sum rules of the bulk stress auto correlation function have been derived. The exact expressions involve static correlation function up to four particles. Because of the non availability of any information about static quadruplet correlation function we use a low order decoupling approximation for this. In this work, we have obtained, separately, the sum rules for the different mechanism of momentum transfer in the fluids. The results are expected to be useful in the study of bulk viscosity of the fluids. (author). 9 refs
QCD effects to Bjorken unpolarized sum rule for νN deep-inelastic scattering
International Nuclear Information System (INIS)
Alekhin, S I; Kataev, A L
2003-01-01
The possibility of the first measurement of Bjorken unpolarized sum rule for F 1 structure function of νN deep-inelastic scattering at neutrino factories is commented. The brief summary of various theoretical contributions to this sum rule is given. Using the next-to-leading set of parton distributions functions, we simulate the expected Q 2 -behaviour and emphasize that its measurement can allow us to determine the value of the QCD strong coupling constant α s with reasonable theoretical uncertainty, dominated by the ambiguity in the existing estimates of the twist-4 non-perturbative 1/Q 2 -effect
Sum Rules in the CFL Phase of QCD at finite density
Manuel, C; Manuel, Cristina; Tytgat, Michel H.G.
2001-01-01
We study the asymmetry between the vector current and axial-vector current correlators in the colour-flavour locking (CFL) phase of QCD at finite density. Using Weinberg's sum rules, we compute the decay constant $f_\\pi$ of the Goldstone modes and find agreement with previous derivations. Using Das's sum rule, we also estimate the contribution of electromagnetic interactions to the mass of the charged modes. Finally, we comment on low temperature corrections to the effective field theory describing the Goldstone bosons.
Charge symmetry breaking in spin dependent parton distributions and the Bjorken sum rule
International Nuclear Information System (INIS)
Cloet, I.C.; Horsley, R.; Londergan, J.T.
2012-04-01
We present the rst determination of charge symmetry violation (CSV) in the spin-dependent parton distribution functions of the nucleon. This is done by determining the rst two Mellin moments of the spin-dependent parton distribution functions of the octet baryons from N f =2+1 lattice simulations. The results are compared with predictions from quark models of nucleon structure. We discuss the contribution of partonic spin CSV to the Bjorken sum rule, which is important because the CSV contributions represent the only partonic corrections to the Bjorken sum rule.
Charge symmetry breaking in spin dependent parton distributions and the Bjorken sum rule
Energy Technology Data Exchange (ETDEWEB)
Cloet, I.C. [Adelaide Univ, SA (Australia). CSSM, School of Chemistry and Physics; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Londergan, J.T. [Indiana Univ., Bloomington, IN (US). Dept. of Physics and Center for Exploration of Energy and Matter] (and others)
2012-04-15
We present the rst determination of charge symmetry violation (CSV) in the spin-dependent parton distribution functions of the nucleon. This is done by determining the rst two Mellin moments of the spin-dependent parton distribution functions of the octet baryons from N{sub f}=2+1 lattice simulations. The results are compared with predictions from quark models of nucleon structure. We discuss the contribution of partonic spin CSV to the Bjorken sum rule, which is important because the CSV contributions represent the only partonic corrections to the Bjorken sum rule.
The Adler sum rule and quark parton distribution functions in nucleon
International Nuclear Information System (INIS)
Niegawa, Akira; Sasaki, Ken.
1975-01-01
The behaviour of the quark parton distribution functions is discussed through the phenomenological analysis of the deep inelastic e-p and e-n data under constraint of the saturation of the Adler sum rule. It is concluded that in the region 0 0 where the Regge parametrization can be applied, anti u(x) is equal to anti d(x), and both behave as const/x, (x 0 will be 0.04--0.05); for x 0 x 0 is given. The rate of convergence of the Adler sum rule is also discussed. (auth.)
Electromagnetic form factors of the ρ meson in light cone QCD sum rules
International Nuclear Information System (INIS)
Aliev, T.M.; Savci, M.
2004-01-01
We investigate the electromagnetic form factors of the ρ meson in light cone QCD sum rules. We find that the ratio of the magnetic and charge form factors is larger than 2 at all values of Q 2 (Q 2 ≥0.5 GeV 2 ). The values of the individual form factors at fixed values of Q 2 predicted by the light cone QCD sum rules are quite different compared to the results of other approaches. These results can be checked in the future, when more precise data on ρ meson form factors is available
Light Cone Sum Rules for gamma*N ->Delta Transition Form Factors
Energy Technology Data Exchange (ETDEWEB)
V.M. Braun; A. Lenz; G. Peters; A. Radyushkin
2006-02-01
A theoretical framework is suggested for the calculation of {gamma}* N {yields} {Delta} transition form factors using the light-cone sum rule approach. Leading-order sum rules are derived and compared with the existing experimental data. We find that the transition form factors in a several GeV region are dominated by the ''soft'' contributions that can be thought of as overlap integrals of the valence components of the hadron wave functions. The ''minus'' components of the quark fields contribute significantly to the result, which can be reinterpreted as large contributions of the quark orbital angular momentum.
Tracing back resonances to families of Regge trajectories. New finite energy sum rules
International Nuclear Information System (INIS)
Mandelbrojt, Jacques.
1975-04-01
An amplitude is supposed to be expressed for large enough energies as a sum of contributions of Regge poles. Calling family of trajectories the set of trajectories which differ by integers from one of them, a correspondance, such that the energy and width of a given resonance depend on only family of trajectories, is established between resonances of the amplitude and families of trajectories. The contribution to the amplitude of each family of trajectories is shown to satisfy the same finite energy sum rules as does the amplitude itself. In these sum rules the resonance approximation can be made where the only resonances that will appear are those which are in correspondence with the family [fr
QCD sum rules in medium and the Okamoto-Nolen-Schiffer anomaly
International Nuclear Information System (INIS)
Hatsuda, T.; Hogaasen, H.; Prakash, M.
1991-01-01
The QCD sum-rule approach for a nuclear medium is developed. The medium dependence of the neutron-proton mass difference calculated from this approach gives effects in nuclei which have direct relevance for the resolution of the Okamoto-Nolen-Schiffer anomaly
The Thomas-Reiche-Kuhn sum rule and the toroid moments
International Nuclear Information System (INIS)
Dubovik, V.M.
1975-01-01
By example of the Thomas-Reiche-Kuhn sum rule a procedure is given for calculating the retardation effects in any E-transition strengths via the toroid moments. The investigation has been performed at the Laboratory of Theoretical Physics, JINR
Calculation of excited vector meson electron widths using QCD sum rules
International Nuclear Information System (INIS)
Geshkenbein, B.V.
1984-01-01
The sum rules are suggested which allow one to calculate the electron widths of excited vector mesons of the PSI, UPSILON, rho meson family assuming the values of their masses to be known. The calculated values of the electron widths agree with experiment
Iso-vector form factors of the delta and nucleon in QCD sum rules
International Nuclear Information System (INIS)
Ozpineci, A.
2012-01-01
Form factors are important non-perturbative properties of hadrons. They give information about the internal structure of the hadrons. In this work, iso-vector axial-vector and iso-vector tensor form factors of the nucleon and the iso-vector axial-vector Δ→N transition form factor calculations in QCD Sum Rules are presented.
SUM-RULES FOR MAGNETIC DICHROISM IN RARE-EARTH 4F-PHOTOEMISSION
THOLE, BT; VANDERLAAN, G
1993-01-01
We present new sum rules for magnetic dichroism in spin polarized photoemission from partly filled shells which give the expectation values of the orbital and spin magnetic moments and their correlations in the ground state. We apply this to the 4f photoemission of rare earths, where the
In-medium QCD sum rules for {omega} meson, nucleon and D meson
Energy Technology Data Exchange (ETDEWEB)
Thomas, Ronny
2008-07-01
The modifications of hadronic properties caused by an ambient nuclear medium are investigated within the scope of QCD sum rules. This is exemplified for the cases of the {omega} meson, the nucleon and the D meson. By virtue of the sum rules, integrated spectral densities of these hadrons are linked to properties of the QCD ground state, quantified in condensates. For the cases of the {omega} meson and the nucleon it is discussed how the sum rules allow a restriction of the parameter range of poorly known four-quark condensates by a comparison of experimental and theoretical knowledge. The catalog of independent four-quark condensates is covered and relations among these condensates are revealed. The behavior of four-quark condensates under the chiral symmetry group and the relation to order parameters of spontaneous chiral symmetry breaking are outlined. In this respect, also the QCD condensates appearing in differences of sum rules of chiral partners are investigated. Finally, the effects of an ambient nuclear medium on the D meson are discussed and relevant condensates are identified. (orig.)
Finite energy sum rules and instantons in the instanton liquid model
International Nuclear Information System (INIS)
Elias, V.; Fang Shi; Steele, T.G.
1998-01-01
We obtain the imaginary part of the direct single-instanton contribution to the pseudoscalar correlator, as defined by the appropriate dispersion relation, in order to derive an explicit integral representation for the instanton contribution to finite energy sum rules in the instanton liquid model. (author)
The nucleon axial isoscalar coupling constant and the Bjorken sum rule
International Nuclear Information System (INIS)
Belyaev, V.M.; Ioffe, B.L.; Kogan, Ya.I.
1984-01-01
The nucleon coupling constant with the axial isoscalar current entering the Bjorken sum rule for the deep inelastic scattering of polarized electrons on a polarized target is calculated in nonperturbative QCD. The result, gsub(A)sup(s) approximately 0.5, is about a factor of two smaller as compared to that of the SU(6) symmetric quark model
On the conductance sum rule for the hierarchical edge states of the fractional quantum hall effect
International Nuclear Information System (INIS)
Ma Zhongshui; Chen Yixin; Su Zhaobin.
1993-09-01
The conductance sum rule for the hierarchical edge channel currents of a Fractional Quantum Hall Effect state is derived analytically within the Haldane-Halperin hierarchy scheme. We provide also an intuitive interpretation for the hierarchical drift velocities of the edge excitations. (author). 12 refs
The influence of gluonic operators on QCD sum rules for baryons
International Nuclear Information System (INIS)
Schall, D.
1982-01-01
In this thesis the operator product expansion (OPE) is extended up to operators of dimension d=10. The coefficient functions are calculated only up to order αsub(s). Thereby the performation of the OPE by means of the Schwinger operator formalism is extensively described. In the final section the sum rules for nucleon and delta are discussed. (orig./HSI) [de
Energy Technology Data Exchange (ETDEWEB)
Chang, Jong Hwa; Lee, Young Ouk; Han, Yin Iu
2000-03-01
This report contains summary information and figures depicting the KAERI photonuclear data library that extends up to 140 MeV of incident photon. The library consists of 143 isotopes from C-12 to Bi-209, providing the photoabsorption cross section and the emission spectra for neutron, proton, deuteron, triton, alpha particles, and all residual nuclides in ENDF6 format. The contents of this report and ENDF-6 format data library are available at http://atom.kaeri.re.kr/.
Analysis of QCD sum rule based on the maximum entropy method
International Nuclear Information System (INIS)
Gubler, Philipp
2012-01-01
QCD sum rule was developed about thirty years ago and has been used up to the present to calculate various physical quantities like hadrons. It has been, however, needed to assume 'pole + continuum' for the spectral function in the conventional analyses. Application of this method therefore came across with difficulties when the above assumption is not satisfied. In order to avoid this difficulty, analysis to make use of the maximum entropy method (MEM) has been developed by the present author. It is reported here how far this new method can be successfully applied. In the first section, the general feature of the QCD sum rule is introduced. In section 2, it is discussed why the analysis by the QCD sum rule based on the MEM is so effective. In section 3, the MEM analysis process is described, and in the subsection 3.1 likelihood function and prior probability are considered then in subsection 3.2 numerical analyses are picked up. In section 4, some cases of applications are described starting with ρ mesons, then charmoniums in the finite temperature and finally recent developments. Some figures of the spectral functions are shown. In section 5, summing up of the present analysis method and future view are given. (S. Funahashi)
Sum rule approach to the study of statistical decay properties of nuclear giant resonances
International Nuclear Information System (INIS)
Adhikari, S.K.; Hussein, M.S.
1987-03-01
Corrections to the well-known statistical sum rule that relates the summed transmission coefficients on the one hand and 2πΓ C.N. .ρ C.N. On the other, in the context of the statistical decay properties of nuclear giant resonances, are discussed. These corrections arise both from pre-equilibrium processes as well as from the giant resonance itself. It is shown that the compound nucleus average width is reduced as a result of these corrections. (Author) [pt
Q2 evolution of generalized Baldin sum rule for the proton
International Nuclear Information System (INIS)
Liang, Y.; Christy, M. E.; Ent, R.; Keppel, C. E.
2006-01-01
The generalized Baldin sum rule for virtual photon scattering, the unpolarized analogy of the generalized Gerasimov-Drell-Hearn integral provides an important way to investigate the transition between perturbative QCD and hadronic descriptions of nucleon structure. This sum rule requires integration of the nucleon structure function F 1 , which until recently had not been measured at low Q 2 and large x, i.e., in the nucleon resonance region. This work uses new data from inclusive electron-proton scattering in the resonance region obtained at Jefferson Lab, in combination with SLAC deep inelastic scattering data, to present first precision measurements of the generalized Baldin integral for the proton in the Q 2 range of 0.3 to 4.0 GeV 2
Predictions for the Dirac C P -violating phase from sum rules
Delgadillo, Luis A.; Everett, Lisa L.; Ramos, Raymundo; Stuart, Alexander J.
2018-05-01
We explore the implications of recent results relating the Dirac C P -violating phase to predicted and measured leptonic mixing angles within a standard set of theoretical scenarios in which charged lepton corrections are responsible for generating a nonzero value of the reactor mixing angle. We employ a full set of leptonic sum rules as required by the unitarity of the lepton mixing matrix, which can be reduced to predictions for the observable mixing angles and the Dirac C P -violating phase in terms of model parameters. These sum rules are investigated within a given set of theoretical scenarios for the neutrino sector diagonalization matrix for several known classes of charged lepton corrections. The results provide explicit maps of the allowed model parameter space within each given scenario and assumed form of charged lepton perturbations.
Experimental check of the Gerasimov-Drell-Hearn sum rule for H1
International Nuclear Information System (INIS)
Dutz, H.; Drachenfels, W. von; Frommberger, F.; Hillert, W.; Klein, F.; Menze, D.; Rohlof, C.; Schoch, B.; Helbing, K.; Speckner, T.; Zeitler, G.; Anton, G.; Bock, A.; Godo, M.; Kiel, B.; Michel, T.; Naumann, J.; Krimmer, J.; Grabmayr, P.; Sauer, M.
2004-01-01
For the first time we checked the fundamental Gerasimov-Drell-Hearn (GDH) sum rule for the proton experimentally in the photon energy range from 0.2-2.9 GeV with the tagged photon facilities at MAMI (Mainz) and ELSA (Bonn). New data of the doubly polarized total cross section difference are presented in the energy range from 1.6 to 2.9 GeV. The contribution to the GDH integral from 0.2-2.9 GeV yields [254±5(stat)±12(syst)] μb with negative contributions in the Regge regime at photon energies above 2.1 GeV. This trend supports the validity of the GDH sum rule
Quark-number susceptibility, thermodynamic sum rule, and the hard thermal loop approximation
International Nuclear Information System (INIS)
Chakraborty, Purnendu; Mustafa, Munshi G.; Thoma, Markus H.
2003-01-01
The quark number susceptibility, associated with the conserved quark number density, is closely related to the baryon and charge fluctuations in the quark-gluon plasma, which might serve as signature for the quark-gluon plasma formation in ultrarelativistic heavy-ion collisions. In addition to QCD lattice simulations, the quark number susceptibility has been calculated recently using a resummed perturbation theory (hard thermal loop resummation). In the present work we show, based on general arguments, that the computation of this quantity neglecting hard thermal loop vertices contradicts the Ward identity and violates the thermodynamic sum rule following from quark number conservation. We further show that the hard thermal loop perturbation theory is consistent with the thermodynamic sum rule
QCD light-cone sum rule estimate of charming penguin contributions in B→ππ
International Nuclear Information System (INIS)
Khodjamirian, A.; Mannel, Th.; Melic, B.
2003-01-01
Employing the QCD light-cone sum rule approach we calculate the B→ππ hadronic matrix element of the current-current operator with c quarks in the penguin topology (''charming penguin''). The dominant contribution to the sum rule is due to the c-quark loop at short distances and is of O(α s ) with respect to the factorizable B→ππ amplitude. The effects of soft gluons are suppressed at least by O(α s m b -2 ). Our result indicates that sizable nonperturbative effects generated by charming penguins at finite m b are absent. The same is valid for the penguin contractions of the current-current operators with light quarks
QCD light-cone sum rule estimate of charming penguin contributions in B→ππ
International Nuclear Information System (INIS)
Khodjamirian, A.; Mannel, Th.; Melic, B.
2003-01-01
Employing the QCD light-cone sum rule approach we calculate the B→ππ hadronic matrix element of the current-current operator with c quarks in the penguin topology ('charming penguin'). The dominant contribution to the sum rule is due to the c-quark loop at short distances and is of O(α s ) with respect to the factorizable B→ππ amplitude. The effects of soft gluons are suppressed at least by O(α s m b -2 ). Our result indicates that sizable nonperturbative effects generated by charming penguins at finite m b are absent. The same is valid for the penguin contractions of the current-current operators with light quarks
Sum-rule analysis of long-wavelength excitations in electron liquids
International Nuclear Information System (INIS)
Ichimaru, Setsuo; Totsuji, Hiroo; Tange, Toshio; Pines, D.
1975-01-01
The properties of the plasma oscillations, the single-particle excitations and the collisional excitations in the classical one-component plasma are investigated in the long-wave-length domain with the aid of moment sum rules. The frequency moments of the dynamic form factor are calculated up to that term which involves the ternary correlation function. The dispersion in the plasma-wave frequency and the strengths of the single-particle and collisional excitations are computed over the thermodynamically stable domain of the plasma parameter, epsilon<=10. It is emphasized that inclusion of the collisional excitations plays a vital part in satisfying various moment-sum rules and in securing agreement with known boundary conditions such as the Vlasov description and molecular-dynamics computations. (auth.)
The Gauge-Invariant Angular Momentum Sum-Rule for the Proton
Shore, G.M.
2000-01-01
We give a gauge-invariant treatment of the angular momentum sum-rule for the proton in terms of matrix elements of three gauge-invariant, local composite operators. These matrix elements are decomposed into three independent form factors, one of which is the flavour singlet axial charge. We further show that the axial charge cancels out of the sum-rule, so that it is unaffacted by the axial anomaly. The three form factors are then related to the four proton spin components in the parton model, namely quark and gluon intrinsic spin and orbital angular momentum. The renormalisation of the three operators is determined to one loop from which the scale dependence and mixing of the spin components is derived under the constraint that the quark spin be scale-independent. We also show how the three form factors can be measured in experiments.
Analysis of the doubly heavy baryons in the nuclear matter with the QCD sum rules
International Nuclear Information System (INIS)
Wang, Zhi-Gang
2012-01-01
In this article, we study the doubly heavy baryon states Ξ cc , Ω cc , Ξ bb and Ω bb in the nuclear matter using the QCD sum rules, and derive three coupled QCD sum rules for the masses, vector self-energies and pole residues. The predictions for the mass-shifts in the nuclear matter ΔM Ξ cc =-1.11simGeV, ΔM Ω cc =-0.33∝GeV, ΔM Ξ bb =-3.37∝GeV and ΔM Ω bb =-1.05∝GeV can be confronted with experimental data in the future. (orig.)
Dependence of Coulomb Sum Rule on the Short Range Correlation by Using Av18 Potential
Modarres, M.; Moeini, H.; Moshfegh, H. R.
The Coulomb sum rule (CSR) and structure factor are calculated for inelastic electron scattering from nuclear matter at zero and finite temperature in the nonrelativistic limit. The effect of short-range correlation (SRC) is presented by using lowest order constrained variational (LOCV) method and the Argonne Av18 and Δ-Reid soft-core potentials. The effects of different potentials as well as temperature are investigated. It is found that the nonrelativistic version of Bjorken scaling approximately sets in at the momentum transfer of about 1.1 to 1.2 GeV/c and the increase of temperature makes it to decrease. While different potentials do not significantly change CSR, the SRC improves the Coulomb sum rule and we get reasonably close results to both experimental data and others theoretical predictions.
International Nuclear Information System (INIS)
Koretune, Susumu
1993-01-01
A sum rule which relates the deep-inelastic polarized structure function g 1 p (x,Q 2 ) to the cross section of photoproduction, (σ 3/2 -σ 1/2 ), is derived. This rule makes it possible to compare the integral of g 1 p (x,Q 2 ) with the Drell-Hearn-Gerasimov sum rule without worrying about contributions from higher twist terms. Further this sum rule shows that there may exist a dynamical mechanism which relates the low energy region to the high energy one. It is conjectured that the spontaneous chiral symmetry breaking of the vacuum is the origin of this mechanism. (author)
The off shell ρ endash ω mixing in the QCD sum rules
International Nuclear Information System (INIS)
Hatsuda, T.
1993-01-01
The q 2 dependence of the ρ - ω mixing amplitude is analyzed with the use of the QCD sum rules and the dispersion relation. In going off shell the mixing decreases, changes sign at q 2 ≅ 0.4 m ρ 2 > 0, and is negative in the space-like region. Implications of this result to the isospin breaking part of the nuclear force are discussed
Energy Technology Data Exchange (ETDEWEB)
Christillin, P [Scuola Normale Superiore, Pisa (Italy); Lipparini, E; Stringari, S [Dipartimento Matematica e Fisica, Trento, Italy
1978-09-25
A sum-rule approach is used to study the influence of surface thickness upon the splitting of dipole and isoscalar quadrupole energies in deformed nuclei. It is shown that hydrodynamic model results are recovered in the case of a deformed skin thickness. A constant skin thickness leads in the dipole case to slightly different predictions which seem in better agreement with experiments. The splitting of the isoscalar quadrupole mode is not sensitive to the surface thickness shape.
Adler-type sum rule, charge symmetry and neutral current in general multi-triplet model
International Nuclear Information System (INIS)
Katuya, Mituaki; Baba, Yoshimitsu; Fujii, Kanji
1975-01-01
We derive Adler-type sum rule extended to general multi-triplet model. Paying attention to roles of the colour degree of freedom, we discuss the charge symmetry property of the weak charged current and the structure functions for ν(ν - )+N→l(l - )+X, and also the structure of the neutral current. A comment is given on implications in our theory of Koike and Konuma's result on the neutral hadronic current. (auth.)
Determination of baryon and baryonic resonance masses from QCD sum rules. Strange baryons
International Nuclear Information System (INIS)
Belyaev, V.M.; Ioffe, B.L.
1982-01-01
The mass differences in baryonic octet Jsup(P)=1/2sup(+), decuplet Jsup(P)=3/2sup(+) and in octet Jsup(P)=3/2sup(-) are calculated basing on the QCD sum rules. The mass differences are expressed through two QCD parameters: the strange current qUark mass and the value of the quark condensate. At the properly chosen values of these parameters all of the mass differences are in a good agreement with experiment
Energy and Regge residues in quantum-mechanical ''QCD'' sum rules
International Nuclear Information System (INIS)
Durand, B.; Durand, L.
1986-01-01
It was shown recently by Fishbane, Kaus, and Gasiorowicz that the residues at the poles of quantum-mechanical two-point functions for arbitrary angular momenta l have an incorrect l dependence when calculated by the sum-rule method used for the analogous problem in QCD. Knowledge of the residues is of interest since they are directly related to particle couplings and decay widths. We develop reliable expressions for the energy and Regge residues using semiclassical methods
Analysis of the scalar doubly charmed hexaquark state with QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang [North China Electric Power University, Department of Physics, Baoding (China)
2017-09-15
In this article, we study the scalar-diquark-scalar-diquark-scalar-diquark type hexaquark state with the QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension 16. We obtain a lowest hexaquark mass of 6.60{sup +0.12}{sub -0.09} GeV, which can be confronted with the experimental data in the future. (orig.)
Leptonic decay constants of heavy quarkonia in effective QCD sum rules
International Nuclear Information System (INIS)
Kiselev, V.V.
1992-01-01
The QCD sum rule scheme, which allows one effectively to take into account the heavy quarkonium peculiarities such as nonrelativistic motion and large mass values of the quarks is considered. The phenomenological scaling law is derived for the leptonic constants with the use of the heavy quarkonium mass spectra. The law describes the data on the values of f φ , f ψ and fγ rather good and predicts f B C . 12 refs.; 2 tabs
Scaling properties of S-wave level density for heavy quarkonium from QCD sum rules
International Nuclear Information System (INIS)
Kiselev, V.V.
1994-01-01
In the framework of a specific scheme of the QCD sum rules for S-wave of the heavy quarkonium one derives an expression, relating the energetic density of quarkonium states and universal characteristics in the heavy quarkonium physics, such as the difference between the masses of a heavy quark Q and meson and the number of heavy quarkonium levels below the threshold decay. 20 refs
On the twist-2 contributions to polarized structure functions and new sum rules
International Nuclear Information System (INIS)
Bluemlein, J.; Kochelev, N.
1996-03-01
The twist-2 contributions to the polarized structure functions in deep inelastic lepton-hadron scattering are calculated including the exchange of weak bosons and using both the operator product expansion and the covariant parton model. A new relation between two structure functions leading to a sequence of new sum rules is found. The light quark mass corrections to the structure functions are derived in lowest order QCD. (orig.)
gsub(ωrhoπ) coupling constant from QCD sum rules
International Nuclear Information System (INIS)
Eletsky, V.L.; Ioffe, B.L.; Kogan, Ya.I.
1982-01-01
QCD sum rules for the vertex function of two vector and one axial vector currents are used to calculate the gsub(ωrhoπ) coupling constant (where gsub(ωrhoπ) is a transition coupling constant for ω → rhoπ process). The obtained value, gsub(ωrhoπ) approximately 17 GeV -1 is in a good agreement with experimental data
Calculation of electromagnetic rhoπ formfactor from QCD sum rules
International Nuclear Information System (INIS)
Eletskij, V.L.; Kogan, Ya.I.
1982-01-01
Electromagnetic rhoπγ form factor at intermediate momentum transfer, 0.7 GeV 2 2 2 , is calculated using QCD sum rules for the vertex function of two vector and one axial-vector currents. In this region the results obtained are consistent within 25% accuracy with the vector meson dominance model predictions and can be regarded as its theoretical ustification
Subtractions in the Adler sum rule and violation of charge symmetry
International Nuclear Information System (INIS)
Dominguez, C.A.; Moreno, H.; Zepeda, A.
1976-01-01
The consequences of a once-subtracted dispersion relation in the derivation of the Adler sum rule are investigated. It is shown that one can expect a breakdown of charge symmetry, of the isotriplet-current hypothesis, and of scaling of the structure functions. These breakdowns are related to the possible presence of a nonzero subtraction function at asymptotic energies and arbitrary q 2 . We also comment about second-class currents and PCAC (partial conservation of axial-vector current) relations
Dispersion theory and sum rules for the non-minimum phase problem in optical spectroscopy
International Nuclear Information System (INIS)
Peiponen, Kai-Erik
2009-01-01
Dispersion relations and sum rules for integer powers of an optical response function are given in the case of the non-minimum phase problem. These relations were obtained using the concept of the Hilbert transform and Blaschke product. The theory presented in this paper is useful both in basic and applied studies of non-minimum phase functions in optics, and also other fields of physics such as high energy physics.
Frustrated Kinetic Energy, the Optical Sum Rule, and the Mechanism of Superconductivity
International Nuclear Information System (INIS)
Chakravarty, S.; Kee, H.; Abrahams, E.
1999-01-01
The basis of the interlayer tunneling theory of high-temperature superconductivity is that the electronic kinetic energy in a direction perpendicular to the copper-oxygen planes is a substantial fraction of the condensation energy. This issue is critically examined, and it is argued from a rigorous conductivity sum rule that the consequences of this theory are consistent with recent optical and penetration depth measurements. copyright 1999 The American Physical Society
Uses of dipole oscillator strength sum rules in second order perturbation theory
International Nuclear Information System (INIS)
Struensee, M.C.
1984-01-01
Certain moments of the dipole oscillator strength distribution of atoms and molecules can be calculated from theory (using sum rules) or deduced from experiment. The present work describes the use of these moments to construct effective distributions which lead to bounds and estimates of physical properties of interest. Asymptotic analysis is then used to obtain the high energy behavior of the oscillator strength density and a previously unknown sum rule for atoms and molecules. A new type of effective distribution, which incorporates the information concerning the asymptotic behavior and the new sum rule, is suggested. This new type of distribution is used to calculate the logarithmic mean excitation energies for the ground states of atomic hydrogen, atomic helium and the negative hydrogen ion. The calculations for atomic helium and the negative hydrogen ion require the evaluation of certain ground state expectation values. These have been calculated using high accuracy wavefunctions containing the nonconventional terms shown by Fock to be necessary for a correct analytic expansion when both electrons are near the nucleus
Spin structure of the neutron ({sup 3}He) and the Bjoerken sum rule
Energy Technology Data Exchange (ETDEWEB)
Meziani, Z.E. [Stanford Univ., CA (United States)
1994-12-01
A first measurement of the longitudinal asymmetry of deep-inelastic scattering of polarized electrons from a polarized {sup 3}He target at energies ranging from 19 to 26 GeV has been performed at the Stanford Linear Accelerator Center (SLAC). The spin-structure function of the neutron g{sub 1}{sup n} has been extracted from the measured asymmetries. The Quark Parton Model (QPM) interpretation of the nucleon spin-structure function is examined in light of the new results. A test of the Ellis-Jaffe sum rule (E-J) on the neutron is performed at high momentum transfer and found to be satisfied. Furthermore, combining the proton results of the European Muon Collaboration (EMC) and the neutron results of E-142, the Bjoerken sum rule test is carried at high Q{sup 2} where higher order Perturbative Quantum Chromodynamics (PQCD) corrections and higher-twist corrections are smaller. The sum rule is saturated to within one standard deviation.
QCD sum rules for D mesons. In-medium effects, chiral symmetry aspects and higher orders
Energy Technology Data Exchange (ETDEWEB)
Buchheim, Thomas
2017-04-11
Heavy open flavor mesons can serve as probes of hot and dense, strongly interacting matter in heavy-ion collisions suitable to mimic the extreme conditions shortly after the big-bang or in compact stars. Thus, the thorough theoretical investigation of medium modifications of D mesons is of utmost importance for the interpretation of the experimental data. Even at finite thermodynamic parameters, such as temperature and density, the non-perturbative framework of QCD sum rules allows for the determination of hadronic properties which are not accessible in perturbative quantum chromodynamics (QCD). By virtue of the separation of scales, long-range effects of hadrons are related to quark and gluon degrees of freedom, where features of the hadron spectrum are linked to condensates parameterizing the complex QCD ground state. This thesis furnishes the conception and calculus of QCD sum rules with emphasis on in-medium effects which are inevitable when addressing such effects in higher order contributions. In this regard, the notion and implications of medium-specific condensates are elucidated. Motivated by the significant numerical impact of four-quark condensates to the ρ meson sum rule we evaluate, for the first time, the corresponding in-medium mass-dimension 6 terms for D mesons tentatively employing the factorization hypothesis. Four-quark condensates containing heavy-quark operators may be included into the sum rule analysis utilizing the in-medium heavy-quark expansion made available here. Particular quark condensates are potential order parameters of chiral symmetry breaking, which is the mass generating mechanism of QCD giving the essential mass fraction to light hadrons. The interplay of altered spectral properties with changing in-medium QCD condensates, i. e. the chiral order parameters, can be studied with chiral partner sum rules. Although, introduced for light spin-1 mesons we foster their generalization to spin-0 open charm mesons demonstrating their
QCD sum rules for D mesons. In-medium effects, chiral symmetry aspects and higher orders
International Nuclear Information System (INIS)
Buchheim, Thomas
2017-01-01
Heavy open flavor mesons can serve as probes of hot and dense, strongly interacting matter in heavy-ion collisions suitable to mimic the extreme conditions shortly after the big-bang or in compact stars. Thus, the thorough theoretical investigation of medium modifications of D mesons is of utmost importance for the interpretation of the experimental data. Even at finite thermodynamic parameters, such as temperature and density, the non-perturbative framework of QCD sum rules allows for the determination of hadronic properties which are not accessible in perturbative quantum chromodynamics (QCD). By virtue of the separation of scales, long-range effects of hadrons are related to quark and gluon degrees of freedom, where features of the hadron spectrum are linked to condensates parameterizing the complex QCD ground state. This thesis furnishes the conception and calculus of QCD sum rules with emphasis on in-medium effects which are inevitable when addressing such effects in higher order contributions. In this regard, the notion and implications of medium-specific condensates are elucidated. Motivated by the significant numerical impact of four-quark condensates to the ρ meson sum rule we evaluate, for the first time, the corresponding in-medium mass-dimension 6 terms for D mesons tentatively employing the factorization hypothesis. Four-quark condensates containing heavy-quark operators may be included into the sum rule analysis utilizing the in-medium heavy-quark expansion made available here. Particular quark condensates are potential order parameters of chiral symmetry breaking, which is the mass generating mechanism of QCD giving the essential mass fraction to light hadrons. The interplay of altered spectral properties with changing in-medium QCD condensates, i. e. the chiral order parameters, can be studied with chiral partner sum rules. Although, introduced for light spin-1 mesons we foster their generalization to spin-0 open charm mesons demonstrating their
Perturbative corrections to Λ_b→Λ form factors from QCD light-cone sum rules
International Nuclear Information System (INIS)
Wang, Yu-Ming; Shen, Yue-Long
2016-01-01
We compute radiative corrections to Λ_b→Λ from factors, at next-to-leading logarithmic accuracy, from QCD light-cone sum rules with Λ_b-baryon distribution amplitudes. Employing the diagrammatic approach factorization of the vacuum-to-Λ_b-baryon correlation function is justified at leading power in Λ/m_b, with the aid of the method of regions. Hard functions entering the factorization formulae are identical to the corresponding matching coefficients of heavy-to-light currents from QCD onto soft-collinear effective theory. The universal jet function from integrating out the hard-collinear fluctuations exhibits richer structures compared with the one involved in the factorization expressions of the vacuum-to-B-meson correlation function. Based upon the QCD resummation improved sum rules we observe that the perturbative corrections at O(α_s) shift the Λ_b→Λ from factors at large recoil significantly and the dominant contribution originates from the next-to-leading order jet function instead of the hard coefficient functions. Having at hand the sum rule predictions for the Λ_b→Λ from factors we further investigate several decay observables in the electro-weak penguin Λ_b→Λ ℓ"+ℓ"− transitions in the factorization limit (i.e., ignoring the “non-factorizable' hadronic effects which cannot be expressed in terms of the Λ_b→Λ from factors), including the invariant mass distribution of the lepton pair, the forward-backward asymmetry in the dilepton system and the longitudinal polarization fraction of the leptonic sector.
Photonuclear physics at intermediate energies
International Nuclear Information System (INIS)
Arruda Neto, J.D.T.
1984-01-01
A review and a description of the state of the art in the field of photonuclear reactions is given. Future perspectives for works in this area in the linear accelarator laboratory at USP, Brazil are presented. (L.C.) [pt
Isospin-breaking nuclear forces in QCD sum rules and Nolen-Schiffer anomaly
International Nuclear Information System (INIS)
Drukarev, E.G.; Ryskin, M.G.
1994-01-01
We use QCD sum rules to investigate isospin-breaking effects in nuclear matter. The isospin-breaking condensate left angle NM vertical stroke uu-dd vertical stroke NM right angle is shown to play an important role. In a reasonable model the neutron becomes (0.9±0.6) MeV more bound than the proton, providing a possible solution for the Nolen-Schiffer anomaly. The various contributions to the value are analysed. The possible consequences for nucleon-nucleon isospin-breaking forces are discussed. ((orig.))
Subtracted Dispersion Relations for In-medium Meson Correlators in QCD Sum Rules
Energy Technology Data Exchange (ETDEWEB)
Florkowski, W; Broniowski, W [The H. Niewodniczanski Institute of Nuclear Physics, Cracow (Poland)
1999-01-01
We analyze subtracted dispersion relations for meson correlators at finite baryon density and temperature. Such relations are needed for QCD sum rules. We point out that importance of scattering terms, as well as finite, well-defined subtraction constants. Both are necessary for consistency, in particular for the equality of the longitudinal and transverse correlators in the limit of the vanishing three-momentum of mesons relative to the medium. We present detailed calculations in various mesonic channels of the Fermi gas of nucleons. (author)
Masses and decay constants of bound states containing fourth family quarks from QCD sum rules
International Nuclear Information System (INIS)
Bashiry, V.; Azizi, K.; Sultansoy, S.
2011-01-01
The heavy fourth generation of quarks that have sufficiently small mixing with the three known standard model families form hadrons. In the present work, we calculate the masses and decay constants of mesons containing either both quarks from the fourth generation or one from the fourth family and the other from known third family standard model quarks in the framework of the QCD sum rules. In the calculations, we take into account two-gluon condensate diagrams as nonperturbative contributions. The obtained results reduce to the known masses and decay constants of the bb and cc quarkonia when the fourth family quark is replaced by the bottom or charm quark.
International Nuclear Information System (INIS)
Nagano, Seido; Ichimaru, Setsuo
1980-01-01
The memory function for the velocity autocorrelation function in a strongly coupled, one-component plasma is analyzed in the short time and long time domains, respectively, with the aid of the frequency-moment sum rules and the hydrodynamic consideration evoking the idea of the generalized Stokes friction. A series of interpolation schemes with successively improved accuracies are then introduced. Numerical investigations of those interpolation schemes clarify the physical origin of the three different types of the velocity autocorrelation function observed in the molecular dynamics simulation at different regimes of the coupling constant. (author)
Sum rules for the ed - NN scattering reactions and microscopic potential field-theoretical approach
International Nuclear Information System (INIS)
Machivariani, A.I.
1996-01-01
The connections between the equal-time commutators of nucleon and photon field-operators and relativistic potential approach of ed - NN scattering equations is established. Namely, it is demonstrated that: 1) equal-time commutator between nucleon field operators generated completeness condition for NN interaction functions, 2) the off-mass shell contributions in γd - NN exchange currents or in microscopic NN potential are determined by equal time commutator between nucleon field operator and photon or nucleon source operators, and 3) equal-time commutators between source operators produce sum rules for same vertex functions and effective potentials [ru
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang; Yan, Ze-Hui [North China Electric Power University, Department of Physics, Baoding (China)
2018-01-15
In this article, we construct the axialvector-diquark-axialvector-antidiquark type currents to interpolate the scalar, axialvector, vector, tensor doubly charmed tetraquark states, and study them with QCD sum rules systematically by carrying out the operator product expansion up to the vacuum condensates of dimension 10 in a consistent way, the predicted masses can be confronted with the experimental data in the future. We can search for those doubly charmed tetraquark states in the Okubo-Zweig-Iizuka super-allowed strong decays to the charmed-meson pairs. (orig.)
International Nuclear Information System (INIS)
Smekhova, A.G.; Andreeva, M.A.
2005-01-01
One elaborated the general formalism on the basis of which one derived the clear expressions for reflection factors of X-ray radiation with a circular polarization from medium magnetized both within surface plane and within reflection plane both for grazing angles and for high grazing angles. The asymmetry of reflection spectra for right- and left-polarized radiation is shown to depend both on nondiagonal components of a susceptibility tensor and on other components in contrast to absorption spectra, so the sum rule to determine the orbital and the spin magnetic moments can not be applied directly to the experimental spectra of reflection [ru
Dispersive approach to the axial anomaly. The t'Hooft's principle and QCD sum rules
International Nuclear Information System (INIS)
Horejsi, J.; Teryaev, O.; Veretin, O.; )
1997-01-01
The dispersive approach to the axial anomaly is revisited. Considering the familiar VVA triangle graph, the anomalous Ward identity is proved in the case of the arbitrary external momenta. It is also commented on a recent claim that the anomaly pole in QCD fails to reproduce the pion pole. In this connection it is emphasized that there is no need to introduce a massless axial meson in the chiral limit. In the framework of QCD sum rules method a constraint for the Borel transform of relevant form factors imposed by the anomaly is considered [ru
Normalization sum rule and spontaneous breaking of U(N) invariance in random matrix ensembles
International Nuclear Information System (INIS)
Canali, C.M.; Kravtsov, V.E.
1995-03-01
It is shown that the two-level correlation function R(s,s') in the invariant random matrix ensembles (RME) with soft confinement exhibits a ''ghost peak'' at s approx. -s'. This lifts the sum rule prohibition for the level number variance to have a Poisson-like term var(n) = ηn that is typical of RME with broken U(N) symmetry. Thus we conclude that the U(N) invariance is broken spontaneously in the RME with soft confinement, η playing the role of an order-parameter. (author). 16 refs, 1 fig
Analyzing Bs - anti Bs mixing. Non-perturbative contributions to bag parameters from sum rules
International Nuclear Information System (INIS)
Mannel, T.; Pivovarov, A.A.; Russian Academy of Sciecnes, Moscow
2007-03-01
We use QCD sum rules to compute matrix elements of the ΔB=2 operators appearing in the heavy-quark expansion of the width difference of the B s mass eigenstates. Our analysis includes the leading-order operators Q and Q S , as well as the subleading operators R 2 and R 3 , which appear at next-to-leading order in the 1/m b expansion. We conclude that the violation of the factorization approximation for these matrix elements due to non-perturbative vacuum condensates is as low as 1-2%. (orig.)
Measurement of αs(Q2) from the Gross endash Llewellyn Smith Sum Rule
International Nuclear Information System (INIS)
Johnson, R.A.; Vakili, M.; Kim, J.H.; Arroyo, C.G.; Bazarko, A.O.; Conrad, J.; King, B.J.; Lefmann, W.C.; McNulty, C.; Mishra, S.R.; Quintas, P.Z.; Romosan, A.; Schellman, H.; Sciulli, F.J.; Seligman, W.G.; Shaevitz, M.H.; Spentzouris, P.; Stern, E.G.; Bernstein, R.H.; Lamm, M.J.; Marsh, W.; McFarland, K.S.; Yu, J.; Bolton, T.; Naples, D.; Barbaro, L. de; Harris, D.A.; Barbaro, P. de; Bodek, A.; Budd, H.; Sakumoto, W.K.; Yang, U.K.; Kinnel, T.; Smith, W.H.
1998-01-01
We extract a set of values for the Gross endash Llewellyn Smith sum rule at different values of 4-momentum transfer squared (Q 2 ), by combining revised CCFR neutrino data with data from other neutrino deep-inelastic scattering experiments for 1 2 2 /c 2 . A comparison with the order α 3 s theoretical predictions yields a determination of α s at the scale of the Z -boson mass of 0.114± 0.009 0.012 . This measurement provides a new and useful test of perturbative QCD at low Q 2 , because of the low uncertainties in the higher order calculations. copyright 1998 The American Physical Society
Berk, A.; Temkin, A.
1985-01-01
A sum rule is derived for the auxiliary eigenvalues of an equation whose eigenspectrum pertains to projection operators which describe electron scattering from multielectron atoms and ions. The sum rule's right-hand side depends on an integral involving the target system eigenfunctions. The sum rule is checked for several approximations of the two-electron target. It is shown that target functions which have a unit eigenvalue in their auxiliary eigenspectrum do not give rise to well-defined projection operators except through a limiting process. For Hylleraas target approximations, the auxiliary equations are shown to contain an infinite spectrum. However, using a Rayleigh-Ritz variational principle, it is shown that a comparatively simple aproximation can exhaust the sum rule to better than five significant figures. The auxiliary Hylleraas equation is greatly simplified by conversion to a square root equation containing the same eigenfunction spectrum and from which the required eigenvalues are trivially recovered by squaring.
International Nuclear Information System (INIS)
Kataev, A.L.
2005-01-01
It is demonstrated that the infrared renormalon calculus indicates that the QCD theoretical expressions for the Gross-Llewellyn Smith sum rule and for the Bjorken polarized and unpolarized ones contain an identical negative twist-4 1/Q 2 correction. This observation is supported by the consideration of the results of calculations of the corresponding twist-4 matrix elements. Together with the indication of the similarity of perturbative QCD contributions to these three sum rules, this observation leads to simple new theoretical relations between the Gross-Llewellyn Smith and Bjorken polarized and unpolarized sum rules in the energy region Q 2 ≥ 1 GeV 2 . The validity of this relation is checked using concrete experimental data for the Gross-Llewellyn Smith and Bjorken polarized sum rules [ru
Estimating the small-x exponent of the structure function g1NS from the Bjorken sum rule
International Nuclear Information System (INIS)
Knauf, Anke; Meyer-Hermann, Michael; Soff, Gerhard
2002-01-01
We present a new estimate of the exponent governing the small-x behavior of the nonsinglet structure function g 1 p-n derived under the assumption that the Bjorken sum rule is valid. We use the world wide average of α s and the NNNLO QCD corrections to the Bjorken sum rule. The structure function g 1 NS is found to be clearly divergent for small x
Spectral sum rules and magneto-roton as emergent graviton in fractional quantum Hall effect
Energy Technology Data Exchange (ETDEWEB)
Golkar, Siavash; Nguyen, Dung X.; Son, Dam T. [Enrico Fermi Institute, James Franck Institute and Department of Physics,University of Chicago, Chicago, Illinois 60637 (United States)
2016-01-05
We consider gapped fractional quantum Hall states on the lowest Landau level when the Coulomb energy is much smaller than the cyclotron energy. We introduce two spectral densities, ρ{sub T}(ω) and ρ̄{sub T}(ω), which are proportional to the probabilities of absorption of circularly polarized gravitons by the quantum Hall system. We prove three sum rules relating these spectral densities with the shift S, the q{sup 4} coefficient of the static structure factor S{sub 4}, and the high-frequency shear modulus of the ground state μ{sub ∞}, which is precisely defined. We confirm an inequality, first suggested by Haldane, that S{sub 4} is bounded from below by |S−1|/8. The Laughlin wavefunction saturates this bound, which we argue to imply that systems with ground state wavefunctions close to Laughlin’s absorb gravitons of predominantly one circular polarization. We consider a nonlinear model where the sum rules are saturated by a single magneto-roton mode. In this model, the magneto-roton arises from the mixing between oscillations of an internal metric and the hydrodynamic motion. Implications for experiments are briefly discussed.
Searching for hidden-charm baryonium signals in QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Chen, Hua-Xing; Zhou, Dan [Beihang University, School of Physics, Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beijing (China); Chen, Wei [University of Saskatchewan, Department of Physics and Engineering Physics, Saskatoon, SK (Canada); Liu, Xiang [Lanzhou University, School of Physical Science and Technology, Lanzhou (China); Lanzhou University, Research Center for Hadron and CSR Physics, Institute of Modern Physics of CAS, Lanzhou (China); Zhu, Shi-Lin [Peking University, School of Physics, State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Peking University, Center of High Energy Physics, Beijing (China)
2016-11-15
We give an explicit QCD sum rule investigation for hidden-charm baryonium states with the quark content u anti ud anti dc anti c, spin J = 0/1/2/3, and of both positive and negative parities. We systematically construct the relevant local hidden-charm baryonium interpolating currents, which can actually couple to various structures, including hidden-charm baryonium states, charmonium states plus two pions, and hidden-charm tetraquark states plus one pion, etc. We do not know which structure these currents couple to at the beginning, but after sum rule analyses we can obtain some information. We find some of them can couple to hidden-charm baryonium states, using which we evaluate the masses of the lowest-lying hidden-charm baryonium states with quantum numbers J{sup P} = 2{sup -}/3{sup -}/0{sup +}/1{sup +}/2{sup +} to be around 5.0 GeV. We suggest to search for hidden-charm baryonium states, especially the one of J = 3{sup -}, in the D-wave J/ψππ and P-wave J/ψρ and J/ψω channels in this energy region. (orig.)
Quasielastic 3Hp and 3Hep scattering at intermediate energies and Glauber sum rules
International Nuclear Information System (INIS)
Blinov, A.V.; Vanyushin, I.A.; Grechko, V.E.
1984-01-01
Differential cross sections and average energy losses of fast protons in reactions p +3 H→psub(F)+X and p+ 3 He → psub(F)+X are studied making use of the ITEP liquid hydrogen bubble chamber of 80-cm diameter exposed to 2.5-GeV/c tritium nuclei (the kinetic energy of the incident protons in the nucleus rest frame Tsub(p)=0.318 GeV) and to 5-GeV/c 3 He nuclei (Tsub(p)=0.978 GeV). The experimental results are compared to predictions based on the sum rules for differential cross sections and average energy losses in the Glauber-Sitenko multiple scattering theory using the completeness condition for the wave functions of the nuclear excited states and the locality of the nuclear potential. The theory and the data are in good agreement at momentum of 2.5 GeV/c. Inconsistence between the Glauber sum rule predictions and the 5 GeV/c data is attributed to the Δ-isobar production in the intermediate state. It is found that possible six-quark bag admixture in the 3 H and 3 He nuclei does not exceed 5%
Photonuclear reactions: astrophysical implications
International Nuclear Information System (INIS)
Nedorezov, V.G.
2005-01-01
Full text: Brief review on astrophysical aspects in photonuclear studies is presented. Main attention is paid on the two kind experiments. The first one was performed at ESRF by GRAAL collaboration using the back scattering laser photons technique to study light speed anisotropy with respect to the dipole of the Cosmic Microwave Background (CMB) radiation. This is a modern analog of the Michelson - Morley experiment. The results obtained are not only methologically different from those of the above mentioned experiments but also provide stronger constrains on the light speed anisotropy in CMB frame. Second subject is related to the electron scattering on exotic nuclei which can play significant role in explosive phenomena such as novae, supernovae and neutron stars. Such approach may be considered as the alternative to traditional low energy accelerator experiments. Exotic nuclei for these purposes can be obtained at CSI (ELISe project). The experiment is foreseen to be installed at the New Experimental Storage Ring (NESR) at RAIR where cooled secondary beams of radioactive ions will collide with an intense electron beam circulating in a small electron storage beam
Liu, C; Liu, J; Yao, Y X; Wu, P; Wang, C Z; Ho, K M
2016-10-11
We recently proposed the correlation matrix renormalization (CMR) theory to treat the electronic correlation effects [Phys. Rev. B 2014, 89, 045131 and Sci. Rep. 2015, 5, 13478] in ground state total energy calculations of molecular systems using the Gutzwiller variational wave function (GWF). By adopting a number of approximations, the computational effort of the CMR can be reduced to a level similar to Hartree-Fock calculations. This paper reports our recent progress in minimizing the error originating from some of these approximations. We introduce a novel sum-rule correction to obtain a more accurate description of the intersite electron correlation effects in total energy calculations. Benchmark calculations are performed on a set of molecules to show the reasonable accuracy of the method.
QCD sum rules for the gluon component of the U(1)sub(A) pseudoscalar meson
International Nuclear Information System (INIS)
Narison, S.; Centre National de la Recherche Scientifique, 13 - Marseille
1981-01-01
Using sum rules based on the positivity and the analyticity of the U(1)sub(A) spectral functions, and within the framework of QCD (quantum chromodynamics), we derive an upper bound Msub(p) approximately less than (0.6 approximately 0.75) GeV to the gluon component of the U(1)sub(A) meson mass. Such a bound could be identified as the exact value of Msub(p) if one accepts a QCD model for the ''continuum'' contribution to the U(1)sub(A) spectral functions. Comparing our result to the observed mass Msub(eta)' approximately equal to 0.96GeV, one could expect an important gluonic contribution to the eta'-mass. This experimental result could be reproduced, if one adds to our result, the quark contribution known to be Msub(q) approximately equal to root(3)msub(π). (author)
Analysis of the mass and width of the X*(3860) with QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang [North China Electric Power University, Department of Physics, Baoding (China)
2017-10-15
In this article, we tentatively assign the X*(3860) to be the Cγ{sub 5} x γ{sub 5}C-type scalar tetraquark state and study its mass and width with the QCD sum rules; special attention is paid to calculating the hadronic coupling constants G{sub Xη{sub cπ}} and G{sub XDD} concerning the tetraquark state. We obtain the values M{sub X} = 3.86 ± 0.09 GeV and Γ{sub X} = 202 ± 146 MeV, which are consistent with the experimental data. The numerical result supports assigning the X*(3860) to be the Cγ{sub 5} x γ{sub 5}C-type scalar tetraquark state. (orig.)
Sum rules and spectral density flow in QCD and in superconformal theories
Directory of Open Access Journals (Sweden)
Costantini Antonio
2014-01-01
Full Text Available We discuss the signature of the anomalous breaking of the superconformal symmetry in N${\\cal N}$ = 1 super Yang Mills theory and its manifestation in the form of anomaly poles. Moreover, we describe the massive deformations of the N${\\cal N}$ = 1 theory and the spectral densities of the corresponding anomaly form factors. These are characterized by spectral densities which flow with the mass deformation and turn the continuum contributions from the two-particle cuts of the intermediate states into poles, with a single sum rule satisfied by each component. The poles can be interpreted as signaling the exchange of a composite axion/dilaton/dilatino (ADD multiplet in the effective Lagrangian. We conclude that global anomalous currents characterized by a single flow in the perturbative picture always predict the existence of composite interpolating fields.
Representation properties, Racah sum rule, and Biedenharn - Elliott identity for Uq(osp(1|2))
International Nuclear Information System (INIS)
Minnaert, P.; Mozrzymas, M.
1998-01-01
It is shown that the universal R matrix in the tensor product of two irreducible representation spaces of the quantum superalgebra U q (osp(1|2)) can be expressed by Clebsch - Gordan coefficients. The Racah sum rule satisfied by U q (osp(1|2)) Racah coefficients and 6-j symbols is derived from the properties of the universal R matrix in the tensor product of three representation spaces. Considering the tensor product of four irreducible representations, it is shown that Biedenharn - Elliott identity holds for U q (osp(1|2)) Racah coefficients and 6-j symbols. A recursion relation for U q (osp(1|2)) 6-j symbols is derived from the Biedenharn endash Elliott identity. copyright 1998 American Institute of Physics
Third family corrections to tri-bimaximal lepton mixing and a new sum rule
International Nuclear Information System (INIS)
Antusch, Stefan; King, Stephen F.; Malinsky, Michal
2009-01-01
We investigate the theoretical stability of the predictions of tri-bimaximal neutrino mixing with respect to third family wave-function corrections. Such third family wave-function corrections can arise from either the canonical normalisation of the kinetic terms or renormalisation group running effects. At leading order both sorts of corrections can be subsumed into a single universal parameter. For hierarchical neutrinos, this leads to a new testable lepton mixing sum rule s=rcosδ+2/3 a (where s,r,a describe the deviations of solar, reactor and atmospheric mixing angles from their tri-bimaximal values, and δ is the observable Dirac CP phase) which is stable under all leading order third family wave-function corrections, as well as Cabibbo-like charged lepton mixing effects
Parton distributions, the Gottfried sum rule and the W charge asymmetry
International Nuclear Information System (INIS)
Martin, A.D.; Stirling, W.J.; Roberts, R.G.
1990-09-01
Preliminary data from the New Muon Collaboration (NMC) allow a precise evaluation of I p-n (x) from a given integral formula for values of x down to 0.004. As x → 0, this integral should converge to a value I p-n (0) = 1/3 (Gottfried sum rule) if the light sea-quark distributions are equal. The NMC value I p-n (0.004) = 0.23 ± 0.03, though appearing to be well short of 1/3, is quite consistent with modern estimates for parton distributions extracted from a wide range of data. These parton distributions are also found to reproduce the W ± rapidity asymmetry recently measured by a European collaboration. (author)
Sum rule for bremsstrahlung cross section for 6Li in the resonating-group method
International Nuclear Information System (INIS)
Lodhi, M.A.K.; Wood, K.E.
1982-01-01
In the method of resonating-group structure, the wave function of 6 Li is assumed to have a single channel of alpha and deuteron substructures in the ground state. It is shown that the intercluster exchange of nucleons is an important effect which causes significant change in the root mean square radius and the dipole transition cross section. Due to lack of symmetry in space coordinates of 6 Li, the dipole operator is not identical to the mean square operator for this sum rule calculation and is expected to display like behavior in similar systems. It is also shown that the deuteron substructure in this nucleus is substantially larger than the alpha substructure. (orig.)
The polarised photon g1γ sum rule at the linear collider and high luminosity B factories
International Nuclear Information System (INIS)
Shore, G.M.
2005-01-01
The sum rule for the first moment of the polarised (virtual) photon structure function g 1 γ (x,Q 2 ;K 2 ) is revisited in the light of proposals for future e + e - colliders. The sum rule exhibits an array of phenomena characteristic of QCD: for real photons (K 2 =0) electromagnetic gauge invariance constrains the first moment to vanish; the limit for asymptotic photon virtuality (m ρ 2 -bar K 2 -bar Q 2 ) is governed by the electromagnetic U A (1) axial anomaly and the approach to asymptopia by the gluonic anomaly; for intermediate values of K 2 , it reflects the realisation of chiral symmetry and is determined by the off-shell radiative couplings of the pseudoscalar mesons; finally, like many polarisation phenomena in QCD, the first moment of g 1 γ involves the gluon topological susceptibility. In this paper, we review the original sum rule proposed by Narison, Shore and Veneziano and extend the relation with pseudoscalar mesons. The possibility of measuring the sum rule in future polarised e + e - colliders is then considered in detail, focusing on the International Linear Collider (ILC) and high luminosity B factories. We conclude that all the above features of the sum rule should be accessible at a polarised collider with the characteristics of SuperKEKB
Photonuclear reactions at intermediate energy
International Nuclear Information System (INIS)
Koch, J.H.
1982-01-01
The dominant feature of photonuclear reactions at intermediate energies is the excitation of the δ resonance and one can therefore use such reactions to study the dynamics of δ propagation in a nucleus. Following an introductory section the author comments on photoabsorption on a single nucleon in Section II. A review of the δ-n Greens function and of the photonuclear amplitude is given in Section III. Results for photoabsorption on 4 He are shown in Section IV and compared with the data. Coherent π 0 photoproduction is discussed in Section V and calculations for 12 C are compared to recent measurements. (Auth.)
International Nuclear Information System (INIS)
Bernard, V.; Kubis, B.; Meissner, U.G.
2005-01-01
We analyze the Fubini-Furlan-Rosetti sum rule in the framework of covariant baryon chiral perturbation theory to leading one-loop accuracy and including next-to-leading-order polynomial contributions. We discuss the relation between the subtraction constants in the invariant amplitudes and certain low-energy constants employed in earlier chiral perturbation theory studies of threshold neutral pion photoproduction off nucleons. In particular, we consider the corrections to the sum rule due to the finite pion mass and show that below the threshold they agree well with determinations based on fixed-t dispersion relations. We also discuss the energy dependence of the electric dipole amplitude E 0+ . (orig.)
QCD determination of the A1-p-π system through vertex light-cone sum rules
International Nuclear Information System (INIS)
Craigie, N.S.; Paver, N.; Riazzudin
1986-01-01
We analyze the rho-A 1 -π system within the context of vertex light-cone sum rules, which are believed to be rigorously satisfied in QCD. It is pointed out that these sum rules provide very strong constraints on the hardronic spectrum and with additional assumptions lead to new predictions, which go significantly beyond those obtained from current algebra in the past. In particular, we report some new results about the rho-A 1 -π couplings and the various transitions form factors in tau-semi-leptonic decays. (orig.)
Magnetic moment for the negative parity Λ→Σ0 transition in light cone QCD sum rules
Directory of Open Access Journals (Sweden)
T.M. Aliev
2016-07-01
Full Text Available The magnetic moment of the Λ→Σ0 transition between negative parity baryons is calculated in framework of the QCD sum rules approach by using the general form of the interpolating currents. The pollution arising from the positive-to-positive, and positive-to-negative parity baryons is eliminated by constructing the sum rules for different Lorentz structures. A comparison of our result with the predictions of the results of other approaches for the positive parity baryons is presented.
1S and $\\overline{MS}$ Bottom Quark Masses from $\\Upsilon$ Sum Rules
Hoang, A.H.
2000-01-01
The bottom quark $1S$ mass, $M_b^{1S}$, is determined using sum rules which relate the masses and the electronic decay widths of the $\\Upsilon$ mesons to moments of the vacuum polarization function. The $1S$ mass is defined as half the perturbative mass of a fictitious ${}^3S_1$ bottom-antibottom quark bound state, and is free of the ambiguity of order $\\Lambda_{QCD}$ which plagues the pole mass definition. Compared to an earlier analysis by the same author, which had been carried out in the pole mass scheme, the $1S$ mass scheme leads to a much better behaved perturbative series of the moments, smaller uncertainties in the mass extraction and to a reduced correlation of the mass and the strong coupling. We arrive at $M_b^{1S}=4.71\\pm 0.03$ GeV taking m_b(\\bar m_b)$ can be reduced if the three-loop corrections to the relation of pole and $\\bar{MS}$ mass are known and if the error in the strong coupling is decreased.
ρ, ω, and φ meson-nucleon scattering lengths from QCD sum rules
International Nuclear Information System (INIS)
Koike, Y.
1995-01-01
The QCD sum rule method is applied to derive a formula for the ρ, ω, and φ meson-nucleon spin-isospin--averaged scattering lengths a ρ,ω,φ . We found that the crucial matrix elements are left-angle bar qγ μ D ν q right-angle N (q=ud) (twist-2 nucleon matrix element) for a ρ,ω and m s left-angle bar ss right-angle N for a φ , and obtained a ρ =0.14±0.07 fm, a ω =0.11±0.06 fm, and a φ =0.035±0.020 fm. These small numbers originate from a common factor 1/(m N +m ρ,ω,φ ). Our result suggests a slight increase (<60 MeV for ρ and ω, and <15 MeV for φ) of the effective mass of these vector mesons in nuclear matter (in the dilute nucleon-gas approximation). The origin of the discrepancy with Hatsuda-Lee was clarified
Revisit assignments of the new excited Ω{sub c} states with QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang; Wei, Xing-Ning; Yan, Ze-Hui [North China Electric Power University, Department of Physics, Baoding (China)
2017-12-15
In this article, we distinguish the contributions of the positive parity and negative parity Ω{sub c} states, study the masses and pole residues of the 1S, 1P, 2S and 2P Ω{sub c} states with the spin J = (1)/(2) and (3)/(2) using the QCD sum rules in a consistent way, and we revisit the assignments of the new narrow excited Ω{sub c}{sup 0} states. The predictions support assigning Ω{sub c}(3000) to the 1P Ω{sub c} state with J{sup P} = (1)/(2){sup -}, assigning Ω{sub c}(3090) to the 1P Ω{sub c} state with J{sup P} = (3)/(2){sup -} or the 2S Ω{sub c} state with J{sup P} = (1)/(2){sup +}, and assigning Ω{sub c}(3119) to the 2S Ω{sub c} state with J{sup P} = (3)/(2){sup +}. (orig.)
0+ tetraquark states from improved QCD sum rules: delving into X(5568)
Zhang, Jian-Rong; Zou, Jing-Lan; Wu, Jin-Yun
2018-04-01
In order to investigate the possibility of the recently observed X(5568) being a 0+ tetraquark state, we make an improvement to the study of the related various configuration states in the framework of the QCD sum rules. Particularly, to ensure the quality of the analysis, condensates up to dimension 12 are included to inspect the convergence of operator product expansion (OPE) and improve the final results of the studied states. We note that some condensate contributions could play an important role on the OPE side. By releasing the rigid OPE convergence criterion, we arrive at the numerical value {5.57}-0.23+0.35 {{GeV}} for the scalar-scalar diquark-antidiquark 0+ state, which agrees with the experimental data for the X(5568) and could support its interpretation in terms of a 0+ tetraquark state with the scalar-scalar configuration. The corresponding result for the axial-axial current is calculated to be {5.77}-0.33+0.44 {{GeV}}, which is still consistent with the mass of X(5568) in view of the uncertainty. The feasibility of X(5568) being a tetraquark state with the axial-axial configuration therefore cannot be definitely excluded. For the pseudoscalar-pseudoscalar and the vector-vector cases, their unsatisfactory OPE convergence make it difficult to find reasonable work windows to extract the hadronic information. Supported by National Natural Science Foundation of China (11475258, 11105223, 11675263) and the Project in NUDT for Excellent Youth Talents
Heavy-to-light form factors: Sum rules on the light cone and beyond
International Nuclear Information System (INIS)
Lucha, Wolfgang; Melikhov, Dmitri; Simula, Silvano
2007-01-01
We report the first systematic analysis of the off-light-cone effects in sum rules for heavy-to-light form factors. These effects are investigated in a model based on scalar constituents, which allows a technically rather simple analysis but has the essential features of the analogous QCD calculation. The correlator relevant for the extraction of the heavy-to-light form factor is calculated in two different ways: first, by adopting the full Bethe-Salpeter amplitude of the light meson and, second, by performing the expansion of this amplitude near the light cone x 2 =0. We demonstrate that the contributions to the correlator from the light-cone term x 2 =0 and the off-light-cone terms x 2 ≠0 have the same order in the 1/m Q expansion. The light-cone correlator, corresponding to x 2 =0, is shown to systematically overestimate the full correlator, the difference being ∼Λ QCD /δ, with δ the continuum subtraction parameter of order 1 GeV. Numerically, this difference is found to be 10 divide 20%
Lensky, Vadim; Hagelstein, Franziska; Pascalutsa, Vladimir; Vanderhaeghen, Marc
2018-04-01
We derive two new sum rules for the unpolarized doubly virtual Compton scattering process on a nucleon, which establish novel low-Q2 relations involving the nucleon's generalized polarizabilities and moments of the nucleon's unpolarized structure functions F1(x ,Q2) and F2(x ,Q2). These relations facilitate the determination of some structure constants which can only be accessed in off-forward doubly virtual Compton scattering, not experimentally accessible at present. We perform an empirical determination for the proton and compare our results with a next-to-leading-order chiral perturbation theory prediction. We also show how these relations may be useful for a model-independent determination of the low-Q2 subtraction function in the Compton amplitude, which enters the two-photon-exchange contribution to the Lamb shift of (muonic) hydrogen. An explicit calculation of the Δ (1232 )-resonance contribution to the muonic-hydrogen 2 P -2 S Lamb shift yields -1 ±1 μ eV , confirming the previously conjectured smallness of this effect.
QCD sum-rules analysis of vector (1-) heavy quarkonium meson-hybrid mixing
Palameta, A.; Ho, J.; Harnett, D.; Steele, T. G.
2018-02-01
We use QCD Laplace sum rules to study meson-hybrid mixing in vector (1-) heavy quarkonium. We compute the QCD cross-correlator between a heavy meson current and a heavy hybrid current within the operator product expansion. In addition to leading-order perturbation theory, we include four- and six-dimensional gluon condensate contributions as well as a six-dimensional quark condensate contribution. We construct several single and multiresonance models that take known hadron masses as inputs. We investigate which resonances couple to both currents and so exhibit meson-hybrid mixing. Compared to single resonance models that include only the ground state, we find that models that also include excited states lead to significantly improved agreement between QCD and experiment. In the charmonium sector, we find that meson-hybrid mixing is consistent with a two-resonance model consisting of the J /ψ and a 4.3 GeV resonance. In the bottomonium sector, we find evidence for meson-hybrid mixing in the ϒ (1 S ) , ϒ (2 S ), ϒ (3 S ), and ϒ (4 S ).
Masses of open-flavour heavy-light hybrids from QCD sum-rules
Energy Technology Data Exchange (ETDEWEB)
Ho, J. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada); Harnett, D. [Department of Physics, University of the Fraser Valley,Abbotsford, BC, V2S 7M8 (Canada); Steele, T.G. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada)
2017-05-29
We use QCD Laplace sum-rules to predict masses of open-flavour heavy-light hybrids where one of the hybrid’s constituent quarks is a charm or bottom and the other is an up, down, or strange. We compute leading-order, diagonal correlation functions of several hybrid interpolating currents, taking into account QCD condensates up to dimension-six, and extract hybrid mass predictions for all J{sup P}∈{0"±, 1"±}, as well as explore possible mixing effects with conventional quark-antiquark mesons. Within theoretical uncertainties, our results are consistent with a degeneracy between the heavy-nonstrange and heavy-strange hybrids in all J{sup P} channels. We find a similar mass hierarchy of 1{sup +}, 1{sup −}, and 0{sup +} states (a 1{sup +} state lighter than essentially degenerate 1{sup −} and 0{sup +} states) in both the charm and bottom sectors, and discuss an interpretation for the 0{sup −} states. If conventional meson mixing is present the effect is an increase in the hybrid mass prediction, and we estimate an upper bound on this effect.
Renormalization group improved bottom mass from {Upsilon} sum rules at NNLL order
Energy Technology Data Exchange (ETDEWEB)
Hoang, Andre H.; Stahlhofen, Maximilian [Wien Univ. (Austria). Fakultaet fuer Physik; Ruiz-Femenia, Pedro [Wien Univ. (Austria). Fakultaet fuer Physik; Valencia Univ. - CSIC (Spain). IFIC
2012-09-15
We determine the bottom quark mass from non-relativistic large-n {Upsilon} sum rules with renormalization group improvement at next-to-next-to-leading logarithmic order. We compute the theoretical moments within the vNRQCD formalism and account for the summation of powers of the Coulomb singularities as well as of logarithmic terms proportional to powers of {alpha}{sub s} ln(n). The renormalization group improvement leads to a substantial stabilization of the theoretical moments compared to previous fixed-order analyses, which did not account for the systematic treatment of the logarithmic {alpha}{sub s} ln(n) terms, and allows for reliable single moment fits. For the current world average of the strong coupling ({alpha}{sub s}(M{sub Z})=0.1183{+-}0.0010) we obtain M{sub b}{sup 1S}=4.755{+-}0.057{sub pert} {+-}0.009{sub {alpha}{sub s}}{+-}0.003{sub exp} GeV for the bottom 1S mass and anti m{sub b}(anti m{sub b})=4.235{+-}0.055{sub pert}{+-}0.003{sub exp} GeV for the bottom MS mass, where we have quoted the perturbative error and the uncertainties from the strong coupling and the experimental data.
Analysis of the QQ anti Q anti Q tetraquark states with QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang [North China Electric Power University, Department of Physics, Baoding (China)
2017-07-15
In this article, we study the J{sup PC} = 0{sup ++} and 2{sup ++} QQ anti Q anti Q tetraquark states with the QCD sum rules, and we obtain the predictions M{sub X(cc} {sub anti} {sub c} {sub anti} {sub c,0}{sup {sub +}{sub +)}} =5.99 ± 0.08 GeV, M{sub X(cc} {sub anti} {sub c} {sub anti} {sub c,2}{sup {sub +}{sub +)}} = 6.09 ± 0.08 GeV, M{sub X(bb} {sub anti} {sub b} {sub anti} {sub b,0}{sup {sub +}{sub +)}} = 18.84 ± 0.09 GeV and M{sub X(bb} {sub anti} {sub b} {sub anti} {sub b,2}{sup {sub +}{sub +)}} = 18.85 ± 0.09 GeV, which can be confronted to the experimental data in the future. Furthermore, we illustrate that the diquark-antidiquark type tetraquark state can be taken as a special superposition of a series of meson-meson pairs and that it embodies the net effects. (orig.)
B→ππ form factors from light-cone sum rules with B-meson distribution amplitudes
Energy Technology Data Exchange (ETDEWEB)
Cheng, Shan; Khodjamirian, Alexander [Theoretische Physik 1, Naturwissenschaftlich-Technische Fakultät,Department Physik, Universität Siegen,Walter-Flex-Strasse 3, 57068 Siegen (Germany); Virto, Javier [Albert Einstein Center for Fundamental Physics,Institute for Theoretical Physics, University of Bern,Sidlerstrasse 5, CH-3012 Bern (Switzerland)
2017-05-30
We study B→ππ form factors using QCD light-cone sum rules with B-meson distribution amplitudes. These form factors describe the semileptonic decay B→ππℓν̄{sub ℓ}, and constitute an essential input in B→ππℓ{sup +}ℓ{sup −} and B→πππ decays. We employ the correlation functions where a dipion isospin-one state is interpolated by the vector light-quark current. We obtain sum rules where convolutions of the P-wave B̄{sup 0}→π{sup +}π{sup 0} form factors with the timelike pion vector form factor are related to universal B-meson distribution amplitudes. These sum rules are valid in the kinematic regime where the dipion state has a large energy and a low invariant mass, and reproduce analytically the known light-cone sum rules for B→ρ form factors in the limit of ρ-dominance and zero width, thus providing a systematics for so far unaccounted corrections to B→ρ transitions. Using data for the pion vector form factor, we estimate finite-width effects and the contribution of excited ρ-resonances to the B→ππ form factors. We find that these contributions amount up to ∼20% in the small dipion mass region where they can be effectively regarded as a nonresonant (P-wave) background to the B→ρ transition.
Effect of Coulomb interaction on the X-ray magnetic circular dichroism spin sum rule in rare earths
Teramura, Y; Tanaka, A; Thole, BT; Jo, T
A deviation from the spin sum rule, which relates the integrated intensity of the X-ray magnetic circular dichroism (MCD) signal to the expectation value of the spin operator S-z ((S-z)), is numerically calculated in the case of the 3d --> 4f absorption for rare earths from the trivalent Ce to Tm.
The spin-dependent structure function of the proton g(1)(p) and a test of the Bjorken sum rule
Czech Academy of Sciences Publication Activity Database
Alekseev, M.; Alexakhin, V. Yu.; Alexandrov, Yu.; Alexeev, G. D.; Amoroso, A.; Austregisilio, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.; Chaberny, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Cotic, D.; Crespo, M.; Dalla Torre, S.; Das, S.; Dasgupta, S. S.; Denisov, O.; Dhara, L.; Diaz, V.; Donskov, S.; Doshita, N.; Duic, V.; Dünnweber, W.; Efremov, A.V.; El Alaoui, A.; Eversheim, P.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger jr., M.; Fischer, H.; Franco, C.; Friedrich, J.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.; Hermann, R.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Höppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Käfer, W.; Kang, D.; Ketzer, B.; Khaustov, G.; Khokhlov, Y.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.; Kolosov, V.; Kondo, K.; Königsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.; Korzenev, A.; Kotzinian, A.; Kouznetsov, O.; Kowalik, K.; Krämer, M.; Kral, A.; Kroumchtein, Z.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.; Lednev, A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Meyer, W.; Michigami, T.; Mikhailov, Y.; Moinester, M.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, S.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.; Nunes, A.S.; Olshevsky, A.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.; Samoylenko, V.; Sandacz, A.; Santos, H.; Sapozhnikov, M.; Sarkar, S.; Savin, I.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlütter, T.; Schmitt, L.; Schopferer, S.; Schröder, W.; Shevchenko, O.; Siebert, H.; Silva, L.; Sinha, L.; Sissakian, A.; Slunecka, M.; Smirnov, G.; Sosio, S.; Sozzi, F.; Srnka, Aleš; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2010-01-01
Roč. 690, č. 5 (2010), s. 466-472 ISSN 0370-2693 R&D Projects: GA MŠk ME 492 Institutional research plan: CEZ:AV0Z20650511 Keywords : deep inelastic scattering * structure function * QCD analysis * Bjorken sum rule Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 5.255, year: 2010
Matrix elements of four-quark operators relevant to life time difference ΔΓBs from QCD sum rules
International Nuclear Information System (INIS)
Huang, C.S.; Zhang Ailin; Zhu, S.L.
2001-01-01
We extract the matrix elements of four-quark operators O L,S relevant to the B s and anti B s life time difference from QCD sum rules. We find that the vacuum saturation approximation works reasonably well, i.e., within 10%. We discuss the implications of our results and compare them with a recent lattice QCD determination. (orig.)
Analysis of diffractive pd to Xd and pp to Xp interactions and test of the finite-mass sum rule
Akimov, Y; Golovanov, L B; Goulianos, K; Gross, D; Malamud, E; Melissinos, A C; Mukhin, S; Nitz, D; Olsen, S; Sticker, H; Tsarev, V A; Yamada, R; Zimmerman, P
1976-01-01
The first moment finite mass sum rule is tested by utilising cross- sections for pp to Xp extracted from recent Fermilab data on pd to Xd and also comparing with CERN ISR data. The dependences on M/sub x//sup 2/, t and s are also discussed. (11 refs).
International Nuclear Information System (INIS)
Khare, A.
1975-01-01
We show that Adler's sum rule for neutrino scattering and Bjorken's inequality for electron-proton scattering are modified if quark has finite anomalous magnetic moment ksub(q). We also show that if ksub(q) is nonzero, there exist fixed poles in spin-flip Compton scattering as well as in charged pion photoproduction. (auth.)
gDsDK*0 and gBsDK*0 coupling constants in QCD sum rules
International Nuclear Information System (INIS)
Şahin, S; Sundu, H; Azizi, K
2012-01-01
In the present study, we calculate the strong coupling constants g D s DK* 0 (800) and g B s DK* 0 (800) within the three-point QCD sum rules approach. We evaluate the correlation function of the considered vertices taking into account both D[B] and K* 0 (800) mesons as off-shell states.
Multi-Higgs doublet models: physical parametrization, sum rules and unitarity bounds
Bento, Miguel P.; Haber, Howard E.; Romão, J. C.; Silva, João P.
2017-11-01
If the scalar sector of the Standard Model is non-minimal, one might expect multiple generations of the hypercharge-1/2 scalar doublet analogous to the generational structure of the fermions. In this work, we examine the structure of a Higgs sector consisting of N Higgs doublets (where N ≥ 2). It is particularly convenient to work in the so-called charged Higgs basis, in which the neutral Higgs vacuum expectation value resides entirely in the first Higgs doublet, and the charged components of remaining N - 1 Higgs doublets are mass-eigenstate fields. We elucidate the interactions of the gauge bosons with the physical Higgs scalars and the Goldstone bosons and show that they are determined by an N × 2 N matrix. This matrix depends on ( N - 1)(2 N - 1) real parameters that are associated with the mixing of the neutral Higgs fields in the charged Higgs basis. Among these parameters, N - 1 are unphysical (and can be removed by rephasing the physical charged Higgs fields), and the remaining 2( N - 1)2 parameters are physical. We also demonstrate a particularly simple form for the cubic interaction and some of the quartic interactions of the Goldstone bosons with the physical Higgs scalars. These results are applied in the derivation of Higgs coupling sum rules and tree-level unitarity bounds that restrict the size of the quartic scalar couplings. In particular, new applications to three Higgs doublet models with an order-4 CP symmetry and with a Z_3 symmetry, respectively, are presented.
QCD sum rules study of the JPC=1-- charmonium Y mesons
International Nuclear Information System (INIS)
Albuquerque, R.M.; Nielsen, M.
2009-01-01
We use QCD sum rules to test the nature of the recently observed mesons Y(4260), Y(4350) and Y(4660), assumed to be exotic four-quark (cc-bar qq-bar) or (cc-bar ss-bar) states with J PC =1 -- . We work at leading order in α s , consider the contributions of higher dimension condensates and keep terms which are linear in the strange quark mass m s . We find for the (cc-bar ss-bar) state a mass m Y =(4.65±0.10) GeV which is compatible with the experimental candidate Y(4660), while for the (cc-bar qq-bar) state we find a mass m Y =(4.49±0.11) GeV, which is still consistent with the mass of the experimental candidate Y(4350). With the tetraquark structure we are working we cannot explain the Y(4260) as a tetraquark state. We also consider molecular D s0 D-bar s * and D 0 D-bar * states. For the D s0 D-bar s * molecular state we get m D s0 D -bar s* =(4.42±0.10) GeV which is consistent, considering the errors, with the mass of the meson Y(4350) and for the D 0 D-bar* molecular state we get m D 0 D -bar*=(4.27±0.10) GeV in excellent agreement with the mass of the meson Y(4260)
Energy Technology Data Exchange (ETDEWEB)
Bernard, V. [Universite Louis Pasteur, Laboratoire de Physique Theorique, Strasbourg Cedex 2 (France); Kubis, B. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie), Bonn (Germany); Meissner, U.G. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie), Bonn (Germany); Forschungszentrum Juelich, Institut fuer Kernphysik (Theorie), Juelich (Germany)
2005-09-01
We analyze the Fubini-Furlan-Rosetti sum rule in the framework of covariant baryon chiral perturbation theory to leading one-loop accuracy and including next-to-leading-order polynomial contributions. We discuss the relation between the subtraction constants in the invariant amplitudes and certain low-energy constants employed in earlier chiral perturbation theory studies of threshold neutral pion photoproduction off nucleons. In particular, we consider the corrections to the sum rule due to the finite pion mass and show that below the threshold they agree well with determinations based on fixed-t dispersion relations. We also discuss the energy dependence of the electric dipole amplitude E{sub 0+}. (orig.)
Renormalization group analysis of B →π form factors with B -meson light-cone sum rules
Shen, Yue-Long; Wei, Yan-Bing; Lü, Cai-Dian
2018-03-01
Within the framework of the B -meson light-cone sum rules, we review the calculation of radiative corrections to the three B →π transition form factors at leading power in Λ /mb. To resum large logarithmic terms, we perform the complete renormalization group evolution of the correlation function. We employ the integral transformation which diagonalizes evolution equations of the jet function and the B -meson light-cone distribution amplitude to solve these evolution equations and obtain renormalization group improved sum rules for the B →π form factors. Results of the form factors are extrapolated to the whole physical q2 region and are compared with that of other approaches. The effect of B -meson three-particle light-cone distribution amplitudes, which will contribute to the form factors at next-to-leading power in Λ /mb at tree level, is not considered in this paper.
Adler Function, Bjorken Sum Rule, and the Crewther Relation to Order αs4 in a General Gauge Theory
International Nuclear Information System (INIS)
Baikov, P. A.; Chetyrkin, K. G.; Kuehn, J. H.
2010-01-01
We compute, for the first time, the order α s 4 contributions to the Bjorken sum rule for polarized electron-nucleon scattering and to the (nonsinglet) Adler function for the case of a generic color gauge group. We confirm at the same order a (generalized) Crewther relation which provides a strong test of the correctness of our previously obtained results: the QCD Adler function and the five-loop β function in quenched QED. In particular, the appearance of an irrational contribution proportional to ζ 3 in the latter quantity is confirmed. We obtain the commensurate scale equation relating the effective strong coupling constants as inferred from the Bjorken sum rule and from the Adler function at order α s 4 .
QCD sum rule approach to the s→dγ contribution to the Ω-→Ξ-γ radiative decay
International Nuclear Information System (INIS)
Nielsen, M.; Barreiro, L.A.; Escobar, C.O.; Rosenfeld, R.
1996-01-01
QCD sum rules are used to calculate the contribution of the short-distance single-quark transition s→dγ to the amplitudes of the hyperon radiative decay Ω - →Ξ - γ. We reevaluate the Wilson coefficient of the effective operator responsible for this transition. We obtain a branching ratio which is comparable to the unitarity limit. copyright 1996 The American Physical Society
Energy Technology Data Exchange (ETDEWEB)
Contreras, C [Department of Physics, Universidad Tecn. Federico Santa Maria, Valparaiso (Chile); Cvetic, G [Department of Physics, Universidad Tecn. Federico Santa Maria, Valparaiso (Chile); Jeong, K S [Department of Physics, Korea Advanced Institute of Science and Technology, Daejon (Korea, Republic of); Lee, Taekoon [Department of Physics, Korea Advanced Institute of Science and Technology, Daejon (Korea, Republic of)
2003-08-01
We recapitulate the method which resums the truncated perturbation series of a physical observable in a way which takes into account the structure of the leading infrared renormalon. We apply the method to the Gross-Llewellyn Smith (GLS) sum rule. By confronting the obtained result with the experimentally extracted GLS value, we determine the value of the QCD coupling parameter, which turns out to agree with the present world average.
The Q2-Dependence of the Gross-Llewellyn Smith Sum Rule and of the Parton Distributions
International Nuclear Information System (INIS)
Kataev, A.L.; AN SSSR, Moscow; Sidorov, A.V.
1994-01-01
We describe the results of our recent work on the determination of the value of the parameter Λ and of the Q 2 -dependence of the Gross-Llewellyn Smith (GLS) sum rule from the experimental data of the CCFR collaboration on neutrino-nucleon deep inelastic scattering, using the Jacobi polynomials QCD analysis. The new information on the Q 2 -dependence of the parton distributions is presented. 37 refs., 3 figs., 3 tabs
International Nuclear Information System (INIS)
Bakulev, Alexander P.
2010-01-01
Using the results on the electromagnetic pion Form Factor (FF) obtained in the O(α s ) QCD sum rules with non-local condensates [A.P. Bakulev, A.V. Pimikov, and N.G. Stefanis, Phys. Rev. D79 (2009) 093010] we determine the effective continuum threshold for the local duality approach. Then we apply it to construct the O(α s 2 ) estimation of the pion FF in the framework of the fractional analytic perturbation theory.
Transition form factors of π0,η and η′ mesons: What can be learned from anomaly sum rule?
International Nuclear Information System (INIS)
Klopot, Yaroslav; Oganesian, Armen; Teryaev, Oleg
2013-01-01
We studied the applications of the anomaly sum rule (ASR) to the transition form factors of light pseudoscalar mesons: π 0 ,η and η ′ . This nonperturbative QCD approach can be used even if the QCD factorization is broken. The status of possible small non-OPE corrections to continuum in comparison to BaBar and Belle data is explored. The accuracy of the applied method and the role of the quark mass contributions are discussed
How Precisely can we Determine the $\\piNN$ Coupling Constant from the Isovector GMO Sum Rule?
Loiseau, B; Thomas, A W
1999-01-01
The isovector GMO sum rule for zero energy forward pion-nucleon scattering iscritically studied to obtain the charged pion-nucleon coupling constant usingthe precise negatively charged pion-proton and pion-deuteron scattering lengthsdeduced recently from pionic atom experiments. This direct determination leadsto a pseudoscalar charged pion-nucleon coupling constant of 14.23 +- 0.09(statistic) +- 0.17 (systematic). We obtain also accurate values for thepion-nucleon scattering lengths.
International Nuclear Information System (INIS)
Oganesian, A.G.
1998-01-01
A method is proposed for estimating unknown vacuum expectation values of high-dimensional operators. The method is based on the idea that the factorization hypothesis is self-consistent. Results are obtained for all vacuum expectation values of dimension-7 operators, and some estimates for dimension-10 operators are presented as well. The resulting values are used to compute corrections of higher dimensions to the Bjorken and Ellis-Jaffe sum rules
QCD Sum-Rule Calculation of the Kinetic Energy and Chromo-Interaction of Heavy Quarks Inside Mesons
Neubert, M
1996-01-01
We present a QCD sum-rule determination of the heavy-quark kinetic energy inside a heavy meson, $-\\lambda_1/2 m_Q$, which is consistent with the field-theory analog of the virial theorem. We obtain $-\\lambda_1\\approx (0.10\\pm 0.05)~\\mbox{GeV}^2$, significantly smaller than a previous sum-rule result, but in good agreement with recent determinations from the analysis of inclusive decays. We also present a new determination of the chromo-magnetic interaction, yielding $\\lambda_2(m_b)=(0.15\\pm 0.03)~\\mbox{GeV}^2$. This implies $m_{B^*}^2-m_B^2=(0.60\\pm 0.12)~\\mbox{GeV}^2$, in good agreement with experiment. As a by-product of our analysis, we derive the QCD sum rules for the three form factors describing the meson matrix element of a velocity-changing current operator containing the gluon field-strength tensor.
International Nuclear Information System (INIS)
Karliner, I.
1975-01-01
The SU(6)-W group structure appears in both current algebra and in the spectroscopy of hadrons. Recently, a considerable progress has taken place in relating these two SU(6)-W structures. The consequences of the proposed correspondence, as it applies to real photon transitions, are investigated in this work. The general structure of such transitions is shown, and a set of resulting selection rules is presented for the multipole character of the photon amplitudes. Many specific amplitudes for both mesons and baryons are worked out and their signs and magnitudes are compared with available experimental data. The saturation of the Drell-Hearn-Gerasimov sum rule for the forward spin-flip amplitude of nucleon Compton scattering was investigated. The sum rule saturation was studied using recent analyses of single pion photoproduction in the region up to photon laboratory energies of 1.2 GeV. The original sum rule is decomposed into separate sum rules originating from different isospin compnents of the electromagnetic current. All three sum rules receive important nonresonant as well as resonant contributions. The isovector-isovector sum rule, whose contributions are known best, is found to be nearly saturated, lending support to the assumptions underlying the sum rules. The failure of the isovector-isoscalar sumrule to be saturated is then presumably to be blamed on inadequate data for inelastic contributions. (Diss. Abs,r. Int., B)
International Nuclear Information System (INIS)
Lepretre, A.
1982-06-01
The total photonuclear absorption cross section for Sn, Ce, Ta, Pb and U has been studied from 25 to 140 MeV using a continuously variable monochromatic photon beam obtained from the annihilation in flight of monoenergetic positrons. The basic experimental results are a set of data giving sums of inclusive multiple photoneutron production cross sections of the form σsup(j) (Esub(γ) = Σsub(i=j)σ(γ,in) for neutron multiplicities ranging from j=1 to 12. From these data the total photonuclear absorption cross section σ(tot : Esub(γ)) has been deduced. It is concluded that Levinger's modified quasi-deuteron model describes the total cross sections reasonably well. When these data are combined with lower energy data and integrated to 140 MeV they indicate the need for an enhancement factor K for the Thomas-Reiche-Kuhn sum rule of 0.76+-0.10. No evidence was found that would indicate an A-dependence for the enhancement factor. From event-by-event records of observed photoneutron multiplicities it was also possible to determine the mean number of photoneutrons, antiν, for each photon energy and the widths W of the multiplicities distributions. From these measurements one also obtains the cross section for the formation of a compound nucleus state excited with the full energy of the absorbed photon [fr
Perturbative corrections to Λ{sub b}→Λ form factors from QCD light-cone sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Yu-Ming [Fakultät für Physik, Universität Wien,Boltzmanngasse 5, 1090 Vienna (Austria); Physik Department T31, Technische Universität München,James-Franck-Straße 1, D-85748 Garching (Germany); Shen, Yue-Long [College of Information Science and Engineering, Ocean University of China,Songling Road 238, Qingdao, Shandong 266100 (China)
2016-02-29
We compute radiative corrections to Λ{sub b}→Λ from factors, at next-to-leading logarithmic accuracy, from QCD light-cone sum rules with Λ{sub b}-baryon distribution amplitudes. Employing the diagrammatic approach factorization of the vacuum-to-Λ{sub b}-baryon correlation function is justified at leading power in Λ/m{sub b}, with the aid of the method of regions. Hard functions entering the factorization formulae are identical to the corresponding matching coefficients of heavy-to-light currents from QCD onto soft-collinear effective theory. The universal jet function from integrating out the hard-collinear fluctuations exhibits richer structures compared with the one involved in the factorization expressions of the vacuum-to-B-meson correlation function. Based upon the QCD resummation improved sum rules we observe that the perturbative corrections at O(α{sub s}) shift the Λ{sub b}→Λ from factors at large recoil significantly and the dominant contribution originates from the next-to-leading order jet function instead of the hard coefficient functions. Having at hand the sum rule predictions for the Λ{sub b}→Λ from factors we further investigate several decay observables in the electro-weak penguin Λ{sub b}→Λ ℓ{sup +}ℓ{sup −} transitions in the factorization limit (i.e., ignoring the “non-factorizable' hadronic effects which cannot be expressed in terms of the Λ{sub b}→Λ from factors), including the invariant mass distribution of the lepton pair, the forward-backward asymmetry in the dilepton system and the longitudinal polarization fraction of the leptonic sector.
Sum rule measurements of the spin-dependent compton amplitude (nucleon spin structure at Q2 = 0)
International Nuclear Information System (INIS)
Babusci, D.; Giordano, G.; Baghaei, H.; Cichocki, A.; Blecher, M.; Breuer, M.; Commeaux, C.; Didelez, J.P.; Caracappa, A.; Fan, Q.
1995-01-01
Energy weighted integrals of the difference in helicity-dependent photo-production cross sections (σ 1/2 - σ 3/2 ) provide information on the nucleon's Spin-dependent Polarizability (γ), and on the spin-dependent part of the asymptotic forward Compton amplitude through the Drell-Hearn-Gerasimov (DHG) sum rule. (The latter forms the Q 2 =0 limit of recent spin-asymmetry experiments in deep-inelastic lepton-scattering.) There are no direct measurements of σ 1/2 or σ 3/2 , for either the proton or the neutron. Estimates from current π-photo-production multipole analyses, particularly for the proton-neutron difference, are in good agreement with relativistic-l-loop Chiral calculations (χPT) for γ but predict large deviations from the DHG sum rule. Either (a) both the 2-loop corrections to the Spin-Polarizability are large and the existing multipoles are wrong, or (b) modifications to the Drell-Hearn-Gerasimov sum rule are required to fully describe the isospin structure of the nucleon. The helicity-dependent photo-reaction amplitudes, for both the proton and the neutron, will be measured at LEGS from pion-threshold to 470 MeV. In these double-polarization experiments, circularly polarized photons from LEGS will be used with SPHICE, a new frozen-spin target consisting of rvec H · rvec D in the solid phase. Reaction channels will be identified in SASY, a large detector array covering about 80% of 4π. A high degree of symmetry in both target and detector will be used to minimize systematic uncertainties
The magnetic moment of the Z_c(3900) as an axialvector tetraquark state with QCD sum rules
Wang, Zhi-Gang
2018-04-01
In this article, we assign the Z_c^± (3900) to be the diquark-antidiquark type axialvector tetraquark state, study its magnetic moment with the QCD sum rules in the external weak electromagnetic field by carrying out the operator product expansion up to the vacuum condensates of dimension 8. We pay special attention to matching the hadron side with the QCD side of the correlation function to obtain solid duality, the routine can be applied to study other electromagnetic properties of the exotic particles.
Higher-twist effects in the B → π transition form factor from QCD light-cone sum rules
Energy Technology Data Exchange (ETDEWEB)
Khodjamirian, Alexander; Rusov, Aleksey [Universitaet Siegen (Germany). Fakultaet IV, Department Physik, Theoretische Physik 1 Walter-Flex-Strasse 3 57068 Siegen
2016-07-01
I report on the progress in calculating new higher-twist corrections to the QCD light-cone sum rule for the B → π transition form factor. First, the expansion of the massive heavy-quark propagator in the external gluonic field near the light-cone was extended to include new terms containing the gluon-field strength derivatives. The resulting analytical expressions for the twist-5 and twist-6 contributions to the correlation function were obtained in a factorized approximation, expressed via the product of the quark-condensate density and the lower-twist pion distribution amplitudes. The numerical analysis of new higher-twist effects is in progress.
Gold-plated mode of CP-violation in decays of B{sub c} meson from QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Kiselev, V V [Russian State Research Center, ' Institute for High Energy Physics' , Protvino, Moscow Region, 142281 (Russian Federation)
2004-10-01
A model-independent method based on the triangle ideology is implemented to extract the CKM-matrix angle {gamma} in the decays of the doubly heavy long-lived meson B{sub c}. We analyse a colour structure of diagrams and conditions to reconstruct two reference triangles by tagging the flavour and CP eigenstates of D{sup 0} - D{sup 0}bar mesons in the fixed exclusive channels. The characteristic branching ratios are evaluated in the framework of QCD sum rules.
International Nuclear Information System (INIS)
Brancus, I.M.; Rebel, H.; Wentz, J.; Corcalciuc, V.
1989-11-01
The original sum-rule model worked out by Wilczynski et al. and successfully used for a global description of complete and incomplete fusion reactions has been extended by a term accounting for dissipative processes of the dinuclear system on its way to fusion. When applying to light and heavy ion collisions with various targets at energies in the transitional region, the new term proves to be rather essential for reproducing the element distributions of the fragments emitted from rather asymmetric systems. (orig.) [de
International Nuclear Information System (INIS)
Lopez, C.
1981-01-01
We write the simplest possible parametrizations of deep inelastic structure functions which satisfy the following requirements: (i) exact compatibility with QCD at the endpoints x = 0,1, to second order; (ii) fulfilment of sum rules to second order; (iii) leading and subleading Regge behaviour. In all we find that, including the QCD scale Λ, such parametrizations describe in a simple manner the three standard functions W 1 , W 2 , W 3 for all x, Q 2 in terms of four to six parameters only (two more if allowing for higher twists). (orig.)
Sum rules for multi-photon spectroscopy of ions in finite symmetry
International Nuclear Information System (INIS)
Kibler, M.; Daoud, M.
1993-05-01
Models describing one- and two-photon transitions for ions in crystalline environments are unified and extended to the case of parity-allowed and parity-forbidden p-photon transitions. The number of independent parameters for characterizing the polarization dependence is shown to depend on an ensemble of properties and rules which combine symmetry considerations and physical models. (author) 26 refs
Status of the B0(S)-bar {B}0(S) Mixing from QCD Spectral Sum Rules
Narison, Stephan
2002-07-01
In this talk, I summarize new results 1 obtained from QCD spectral sum rules (QSSR), on the bag constant parameters entering in the analysis of the B0(s)-bar {B}0(s) mass-differences. Taking the average of the results from the Laplace and moment sum rules, one obtains to order α s: fB√ {hat {B}_B} ˜= (229 ± 55) GeV, fB{s}√ {BB_{s}}/f_B√ {BB} ˜= 1.18 ± 0.03, in units where fπ = 130.7 MeV. Combined with the experimental data on the mass-differences ΔMd,s, one obtains the constraint on the CKM weak mixing angle: |Vts/Vtd|2 ≥ 20.2(1.3). Alternatively, using the weak mixing angle from the analysis of the unitarity triangle and the data on ΔMd, one predicts ΔMs = 18.3(2.1) ps-1 in agreement with the present experimental lower bound and within the reach of Tevatron 2.
The spin structure function g1p of the proton and a test of the Bjorken sum rule
Directory of Open Access Journals (Sweden)
C. Adolph
2016-02-01
Full Text Available New results for the double spin asymmetry A1p and the proton longitudinal spin structure function g1p are presented. They were obtained by the COMPASS Collaboration using polarised 200 GeV muons scattered off a longitudinally polarised NH3 target. The data were collected in 2011 and complement those recorded in 2007 at 160 GeV, in particular at lower values of x. They improve the statistical precision of g1p(x by about a factor of two in the region x≲0.02. A next-to-leading order QCD fit to the g1 world data is performed. It leads to a new determination of the quark spin contribution to the nucleon spin, ΔΣ, ranging from 0.26 to 0.36, and to a re-evaluation of the first moment of g1p. The uncertainty of ΔΣ is mostly due to the large uncertainty in the present determinations of the gluon helicity distribution. A new evaluation of the Bjorken sum rule based on the COMPASS results for the non-singlet structure function g1NS(x,Q2 yields as ratio of the axial and vector coupling constants |gA/gV|=1.22±0.05 (stat.±0.10 (syst., which validates the sum rule to an accuracy of about 9%.
Analysis of J/psi → etasub(c)γ decay by the method of QCD sum rules
International Nuclear Information System (INIS)
Bejlin, V.A.; Radyushkin, A.V.
1984-01-01
The radiative M1 transitions in charmonium are analyzed by the method of QCD sum rules taking into account nonperturbative corrections O( ). The dependence of the result on the choice of the parameter is investigated. The account of the lower nonperturbative corrections to the amplitude, describing radiation M1-transitions in charmonium, changes slightly the result for the decay widths GITA(J/psi → etasub(c)γ). The calculations show that the values of parameter phi, somewhat larger than the standard, one, result in shifting the theoretical values for GITA(J/psi → etasub(c)γ) in the direction of the experimental one, however no unambiguous conclusion on phi deviation of the standard value can be drawn without account for the contribution from higher dimensions
International Nuclear Information System (INIS)
Tas, Murat; Tanatar, B.
2008-01-01
We calculate the collective excitation modes of strongly coupled bilayer charged Bose systems. We employ the dielectric matrix formulation to study the correlation effects within the random-phase approximation (RPA), the self consistent field approximation Singwi, Tosi, Land, and Sjoelander (STLS), and the quasilocalized charge approximation (QLCA), which satisfies the third-frequency-moment ( 3 >) sum rule. We find that the QLCA predicts a long-wavelength correlation-induced energy gap in the out-of-phase plasmon mode, similar to the situation in electronic bilayer systems. The energy gap and the plasmon density of states are studied as a function of interlayer separation and coupling parameter r s . The results should be helpful for experimental investigations
Energy Technology Data Exchange (ETDEWEB)
Hasselgren, L; Fahlander, C; Edvardson, L O; Thun, J E; Falk, F; Ghumman, B S
1975-04-01
The orientation precession technique, REPREC, for measurements of quadrupole moments is described. The application of REPREC to the measurement of the static electric quadrupole moments of the first excited 2/sup +/-states in /sup 108/ /sup 110/Pd is presented. The possibility to measure the matrix product P/sub 4/ = M/sub 02/M/sub 22/,M/sub 02/M/sub 22/ is also discussed. Such measurements are presented for /sup 108/ /sup 110/Pd. The results of these measurements are P/sub 4/O for both /sup 108/Pd and /sup 110/Pd. For /sup 108/Pd the quadrupole moment of the first excited 2/sup +/-state was found to be -.66 +- .18 eb and for /sup 110/Pd -.72 +- .14 eb. Intrinsic nuclear properties for /sup 106 -110/Pd are derived using the sum rules suggested by Kumar.
International Nuclear Information System (INIS)
Guellenstern, S.
1991-09-01
Using the technique of Cherniak and Zhitnitzky we have calculated the wavefunctions of ρ(770) and Φ(1020) within the framework of QCD sum rules. Whereas the standard approach assumes light-like distances of the quarks (z 2 = 0), we also have taken into account higher order terms in z 2 . Thus, we obtained non-vanishing orbital angular momentum contributions. The first few moments of various invariant functions have been calculated with the help of an especially developed REDUCE program package. In zeroth order (z 2 = 0) our results of the reconstructed wavefunctions agree with those in the literature. However, we got first order contributions in z 2 of an amount of almost 10% of the corresponding zeroth order. (orig.)
The Adler-Weisberger sum rule and the sigma-Commutator for the Kaon-Neutron system
International Nuclear Information System (INIS)
Rodriguez-Vargas, A.M.; Violini, G.
1980-01-01
The axial coupling constant is determined from Kp and Kn Adler-Weisberger sum rule, in correspondence with different anti K N unphysical region parameterizations. Moreover a new calculation of the sigma-term is presented. It is shown that by using Kn data it is possible to reduce considerably the error on sigma sup(KK)sub(NN) with respect to the analogous calculation for Kp, but that an accurate determination requires a good value for the psub(3/2) anti K N scattering length. By preferring the solutions which lead to a positive sigma-term, one obtains sigma sup(KK)sub(NN) = 638 +- 438 MeV. (orig.) 891 HSI/orig. 892 HIS
Adler function, sum rules and Crewther relation of order O(αs4): The singlet case
International Nuclear Information System (INIS)
Baikov, P.A.; Chetyrkin, K.G.; Kühn, J.H.; Rittinger, J.
2012-01-01
The analytic result for the singlet part of the Adler function of the vector current in a general gauge theory is presented in five-loop approximation. Comparing this result with the corresponding singlet part of the Gross-Llewellyn Smith sum rule (Baikov et al., 2010 ), we successfully demonstrate the validity of the generalized Crewther relation for the singlet part. This provides a non-trivial test of both our calculations and the generalized Crewther relation. Combining the result with the already available non-singlet part of the Adler function (Baikov et al., 2008 , Baikov et al., 2010 ) we arrive at the complete O(α s 4 ) expression for the Adler function and, as a direct consequence, at the complete O(α s 4 ) correction to the e + e - annihilation into hadrons in a general gauge theory.
Analysis of the strong decays Ds3*(2860) → DK, D*K with QCD sum rules
International Nuclear Information System (INIS)
Wang, Zhi-Gang
2016-01-01
In this article, we assign the D s3 * (2860) to be a D-wave c anti s meson, study the hadronic coupling constants G D s3 * (2860)DK and G D s3 * (2860)D * K with the three-point QCD sum rules, and calculate the partial decay widths Γ(D s3 * (2860) → D * K) and Γ(D s3 * (2860) → DK). The predicted ratio R = Γ(D s3 * (2860) → D * K)/Γ(D s3 * (2860) → DK) = 0.57±0.38 cannot reproduce the experimental value R = Br(D sJ * (2860) → D * K)/Br(D sJ * (2860) → DK) = 1.10±0.15±0.19. (orig.)
Analysis of the strong decays Ds3 *(2860) → DK, D*K with QCD sum rules
Wang, Zhi-Gang
2016-10-01
In this article, we assign the D_{s3}^{ast}(2860) to be a D-wave c bar{s} meson, study the hadronic coupling constants G_{D_{s3}^{ast}(2860)DK} and G_{D_{s3}^{ast} (2860)D^{ast}K} with the three-point QCD sum rules, and calculate the partial decay widths Γ (D_{s3}^{ast} (2860) → D^{ast}K) and Γ (D_{s3}^{ast}(2860) → DK) . The predicted ratio R = Γ (D_{s3}^{ast} (2860)→ D^{ast}K)/Γ (D_{s3}^{ast} (2860)→ DK) = 0.57± 0.38 cannot reproduce the experimental value R = Br(D_{sJ}^{ast} (2860)→ D^{ast}K)/Br (D_{sJ}^{ast} (2860)→ DK) = 1.10 ± 0.15 ± 0.19.
Some issues in photonuclear physics
International Nuclear Information System (INIS)
Tzara, C.
1980-11-01
Let us consider the simplest processes induced by the electromagnetic interaction, the emission or absorption of one photon. Their cross sections are unambiguously related to definite characteristics of the target, the charge and current form factors. In reality what is measured is different because higher order e.m. effects are unavoidable: (1) in photonuclear reactions, the radiative corrections, which are indeed negligible as long as the velocity imparted to the target or the emitted particles is small; (2) in contrast, the corrections to Born aproximation in electron scattering: distortion of the electron wave; two-photon exchange; radiative corrections, are far from negligible and pose eventually difficult problems. For the purpose of the following discussion, these will be considered as correctly handled, so that the final outcomes of the measurements are really form factors. At high energy, the so-called shadow effect comes into play. Whatever model is invoked to interpret it, the process is a one-photon and, as such, provides a form factor
Photonuclear Physics in Radiation Transport - II: Implementation
International Nuclear Information System (INIS)
White, M.C.; Little, R.C.; Chadwick, M.B.; Young, P.G.; MacFarlane, R.E.
2003-01-01
This is the second of two companion papers. The first paper describes model calculations and nuclear data evaluations of photonuclear reactions on isotopes of C, O, Al, Si, Ca, Fe, Cu, Ta, W, and Pb for incident photon energies up to 150 MeV. This paper describes the steps taken to process these files into transport libraries and to update the Monte Carlo N-Particle (MCNP) and MCNPX radiation transport codes to use tabular photonuclear reaction data. The evaluated photonuclear data files are created in the standard evaluated nuclear data file (ENDF) format. These files must be processed by the NJOY data processing system into A Compact ENDF (ACE) files suitable for radiation transport calculations. MCNP and MCNPX have been modified to use these new data in a self-consistent and fully integrated manner. Verification problems were used at each step along the path to check the integrity of the methodology. The resulting methodology and tools provide a comprehensive system for using photonuclear data in radiation transport calculations. Also described are initial validation simulations used to benchmark several of the photonuclear transport tables
Relativistic chiral SU(3) symmetry, large Nc sum rules and meson-baryon scattering
International Nuclear Information System (INIS)
Lutz, M.F.M.; Kolomeitsev, E.E.
2001-05-01
The relativistic chiral SU(3) Lagrangian is used to describe kaon-nucleon scattering imposing constraints from the pion-nucleon sector and the axial-vector coupling constants of the baryon octet states. We solve the covariant coupled-channel Bethe-Salpeter equation with the interaction kernel truncated at chiral order Q 3 where we include only those terms which are leading in the large N c limit of QCD. The baryon decuplet states are an important explicit ingredient in our scheme, because together with the baryon octet states they form the large N c baryon ground states of QCD. Part of our technical developments is a minimal chiral subtraction scheme within dimensional regularization, which leads to a manifest realization of the covariant chiral counting rules. All SU(3) symmetry-breaking effects are well controlled by the combined chiral and large N c expansion, but still found to play a crucial role in understanding the empirical data. We achieve an excellent description of the data set typically up to laboratory momenta of p lab ≅ 500 MeV. (orig.)
Kohut, Sviataslau V; Staroverov, Viktor N
2013-10-28
The exchange-correlation potential of Kohn-Sham density-functional theory, vXC(r), can be thought of as an electrostatic potential produced by the static charge distribution qXC(r) = -(1∕4π)∇(2)vXC(r). The total exchange-correlation charge, QXC = ∫qXC(r) dr, determines the rate of the asymptotic decay of vXC(r). If QXC ≠ 0, the potential falls off as QXC∕r; if QXC = 0, the decay is faster than coulombic. According to this rule, exchange-correlation potentials derived from standard generalized gradient approximations (GGAs) should have QXC = 0, but accurate numerical calculations give QXC ≠ 0. We resolve this paradox by showing that the charge density qXC(r) associated with every GGA consists of two types of contributions: a continuous distribution and point charges arising from the singularities of vXC(r) at each nucleus. Numerical integration of qXC(r) accounts for the continuous charge but misses the point charges. When the point-charge contributions are included, one obtains the correct QXC value. These findings provide an important caveat for attempts to devise asymptotically correct Kohn-Sham potentials by modeling the distribution qXC(r).
Recommended evaluation procedure for photonuclear cross section
Energy Technology Data Exchange (ETDEWEB)
Lee, Young-Ouk; Chang, Jonghwa; Fukahori, Tokio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
1998-03-01
In order to generate photonuclear cross section library for the necessary applications, data evaluation is combined with theoretical evaluation, since photonuclear cross sections measured cannot provide all necessary data. This report recommends a procedure consisting of four steps: (1) analysis of experimental data, (2) data evaluation, (3) theoretical evaluation and, if necessary, (4) modification of results. In the stage of analysis, data obtained by different measurements are reprocessed through the analysis of their discrepancies to a representative data set. In the data evaluation, photonuclear absorption cross sections are evaluated via giant dipole resonance and quasi-deutron mechanism. With photoabsorption cross sections from the data evaluation, theoretical evaluation is applied to determine various decay channel cross sections and emission spectra using equilibrium and preequilibrium mechanism. After this, the calculated results are compared with measured data, and in some cases the results are modified to better describe measurements. (author)
Energy Technology Data Exchange (ETDEWEB)
Kominis, Ioannis [Princeton Univ., NJ (United States)
2001-01-01
This thesis presents the results of E-94010, an experiment at Thomas Jefferson National Accelerator Facility (TJNAF) designed to study the spin structure of the neutron at low momentum transfer, and to test the “extended” Gerasimov-Drell-Hearn (GDH) sum rule. The first experiment of its kind, it was performed in experimental Hall-A of TJNAF using a new polarized ^{3}He facility. It has recently been shown that the GDH sum rule and the Bjorken sum rule are both special examples of a more general sum rule that applies to polarized electron scattering off nucleons. This generalized sum rule, due to Ji and Osborne, reduces to the GDH sum rule at Q^{2} = 0 and to the Bjorken sum rule at Q^{2} >> 1 GeV^{2}. By studying the Q^{2} evolution of the extended GDH sum, one learns about the transition from quark-like behavior to hadronic-like behavior. We measured inclusive polarized cross sections by scattering high energy polarized electrons off the new TJNAF polarized ^{3}He target with both longitudinal and transverse target orientations. The high density ^{3}He target, based on optical pumping and spin exchange, was used as an effective neutron target. The target maintained a polarization of about 35% at beam currents as high as 151tA. We describe the precision ^{3}He polarimetry leading to a systematic uncertainty of the target polarization of 4% (relative). A strained GaAs photocathode was utilized in the polarized electron gun, which provided an electron beam with a polarization of about 70%, known to 3% (relative). By using six different beam energies (between 0.86 and 5.06 GeV) and a fixed scattering angle of 15.5°, a wide kinematic coverage was achieved, with 0.02 GeV^{2}< Q^{2} <1 GcV^{2} and 0.5 GeV< W < 2.5 GeV for the squared momentum transfer and invariant mass, respectively. From the measured cross sections we extract the ^{3}He spin structure functions g$3 He
International Nuclear Information System (INIS)
Kondratyuk, S.; Kubodera, K.; Myhrer, F.; Scholten, O.
2004-01-01
The Adler-Weisberger and Goldberger-Miyazawa-Oehme sum rules are calculated within a relativistic, unitary and crossing symmetric dynamical model for pion-nucleon scattering using two different methods: (1) by evaluating the scattering amplitude at the corresponding low-energy kinematics and (2) by evaluating the sum-rule integrals with the calculated total cross section. The discrepancy between the results of the two methods provides a measure of the breaking of analyticity and chiral symmetry in the model. The contribution of the Δ resonance, including its dressing with meson loops, is discussed in some detail and found to be small
Dufner, Michael; Leising, Daniel; Gebauer, Jochen E
2016-05-01
How are people who generally see others positively evaluated themselves? We propose that the answer to this question crucially hinges on the content domain: We hypothesize that Agency follows a "zero-sum principle" and therefore people who see others ashighin Agency are perceived aslowin Agency themselves. In contrast, we hypothesize that Communion follows a "non-zero-sum principle" and therefore people who see others ashighin Communion are perceived ashighin Communion themselves. We tested these hypotheses in a round-robin and a half-block study. Perceiving others as agentic was indeed linked to being perceived as low in Agency. To the contrary, perceiving others as communal was linked to being perceived as high in Communion, but only when people directly interacted with each other. These results help to clarify the nature of Agency and Communion and offer explanations for divergent findings in the literature. © 2016 by the Society for Personality and Social Psychology, Inc.
Modern status of photonuclear data
Varlamov, V. V.; Ishkhanov, B. S.
2017-09-01
The reliability of experimental cross sections obtained for (γ, 1 n), (γ, 2 n), and (γ, 3 n) partial photoneutron reactions using beams of quasimonoenergetic annihilation photons and bremsstrahlung is analyzed by employing data for a large number of medium-heavy and heavy nuclei, including those of 63,65Cu, 80Se, 90,91,94Zr, 115In, 112-124Sn, 133Cs, 138Ba, 159Tb, 181Ta, 186-192Os, 197Au, 208Pb, and 209Bi. The ratios of the cross sections of definite partial reactions to the cross section of the neutron-yield reaction, F i = σ(γ, in)/ σ(γ, xn), are used as criteria of experimental-data reliability. By definition, positive values of these ratios should not exceed the upper limits of 1.00, 0.50, 0.33,... for i = 1, 2, 3,..., respectively. For many nuclei, unreliable values of the above ratios were found to correlate clearly in various photon-energy regions F i with physically forbidden negative values of cross sections of partial reactions. On this basis, one can conclude that correspondent experimental data are unreliable. Significant systematic uncertainties of the methods used to determine photoneutron multiplicity are shown to be the main reason for this. New partial-reaction cross sections that satisfy the above data-reliability criteria were evaluated within an experimental-theoretical method [ σ eval(γ, in) = F i theor (γ, in) × σ expt(γ, xn)] by employing the ratios F i theor (γ, in) calculated on the basis of a combined photonuclear-reaction model. It was obtained that cross sections evaluated in this way deviate substantially from the results of many experiments performed via neutron-multiplicity sorting, but, at the same time, agree with the results of alternative activation experiments. Prospects of employing methods that would provide, without recourse to photoneutron-multiplicity sorting, reliable data on cross sections of partial photoneutron reactions are discussed.
Photonuclear experiments using large acceptance detectors
International Nuclear Information System (INIS)
Mecking, B.A.
1984-08-01
Experimental programs in photonuclear physics are discussed. In experiments concentrate on the combined use of low intensity (real and virtual) photon beams and large acceptance detectors for the detection of multiple particle final states. Count rate estimates and the consequences for the operation of a high intensity accelerator are given. (orig.)
Photonuclear studies in the few nucleon system
International Nuclear Information System (INIS)
Weiss, M.S.
1975-02-01
A brief review of photonuclear reactions in few nucleon systems is presented with comparison of theory with experiment. Discrepancies are examined and recent and current research aimed at resolving these problems are discussed. Emphasis is placed on two and three body photodisintegration. (33 figures) (U.S.)
Photonuclear physics with low intensity photon beams
International Nuclear Information System (INIS)
Mecking, B.A.
1985-01-01
Experiments in photonuclear physics are discussed that require a low intensity photon beam and large acceptance detectors. This combination is especially suitable for the investigation of photoprocesses on nucleons and light nuclei. A specific experimental setup for the electron stretcher ring ELSA is presented. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Baru, V. [Institut fuer Theoretische Physik II, Ruhr-Universitaet Bochum, D-44870 Bochum (Germany); Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Theoretical and Experimental Physics, B. Cheremushinskaya 25, 117218 Moscow (Russian Federation); Hanhart, C. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany); Hoferichter, M., E-mail: hoferichter@hiskp.uni-bonn.de [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Institute of Nuclear and Particle Physics and Department of Physics and Astronomy, Ohio University, Athens, OH 45701 (United States); Kubis, B. [Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universitaet Bonn, D-53115 Bonn (Germany); Nogga, A. [Institut fuer Kernphysik and Juelich Center for Hadron Physics, Forschungszentrum Juelich, D-52425 Juelich (Germany); Institute for Advanced Simulation, Forschungszentrum Juelich, D-52425 Juelich (Germany)
2011-12-15
We use chiral perturbation theory (ChPT) to calculate the {pi}{sup -}d scattering length with an accuracy of a few percent, including isospin-violating corrections in both the two- and three-body sectors. In particular, we provide the technical details of a recent letter (Baru et al., 2011) , where we used data on pionic deuterium and pionic hydrogen atoms to extract the isoscalar and isovector pion-nucleon scattering lengths a{sup +} and a{sup -}. We study isospin-breaking contributions to the three-body part of a{sub {pi}}{sup -}{sub d} due to mass differences, isospin violation in the {pi}N scattering lengths, and virtual photons. This last class of effects is ostensibly infrared enhanced due to the smallness of the deuteron binding energy. However, we show that the leading virtual-photon effects that might undergo such enhancement cancel, and hence the standard ChPT counting provides a reliable estimate of isospin violation in a{sub {pi}}{sup -}{sub d} due to virtual photons. Finally, we discuss the validity of the Goldberger-Miyazawa-Oehme sum rule in the presence of isospin violation, and use it to determine the charged-pion-nucleon coupling constant.
The Spin-dependent Structure Function of the Proton $g_{1}^p$ and a Test of the Bjorken Sum Rule
Alekseev, M.G.; Alexandrov, Yu.; Alexeev, G.D.; Amoroso, A.; Austregesilo, A.; Badelek, B.; Balestra, F.; Ball, J.; Barth, J.; Baum, G.; Bedfer, Y.; Bernhard, J.; Bertini, R.; Bettinelli, M.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Bravar, A.; Bressan, A.; Brona, G.; Burtin, E.; Bussa, M.P.; Chaberny, D.; Cotic, D.; Chiosso, M.; Chung, S.U.; Cicuttin, A.; Colantoni, M.; Crespo, M.L.; Dalla Torre, S.; Das, S.; Dasgupta, S.S.; Denisov, O.Yu.; Dhara, L.; Diaz, V.; Donskov, S.V.; Doshita, N.; Duic, V.; Dunnweber, W.; Efremov, A.; El Alaoui, A.; Eversheim, P.D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M., Jr.; Fischer, H.; Franco, C.; Friedrich, J.M.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O.P.; Gazda, R.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmuller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Haas, F.; von Harrach, D.; Hasegawa, T.; Heinsius, F.H.; Hermann, R.; Herrmann, F.; Hess, C.; Hinterberger, F.; Horikawa, N.; Hoppner, Ch.; d'Hose, N.; Ilgner, C.; Ishimoto, S.; Ivanov, O.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jasinski, P.; Jegou, G.; Joosten, R.; Kabuss, E.; Kafer, W.; Kang, D.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koblitz, S.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konopka, R.; Konorov, I.; Konstantinov, V.F.; Korzenev, A.; Kotzinian, A.M.; Kouznetsov, O.; Kowalik, K.; Kramer, M.; Kral, A.; Kroumchtein, Z.V.; Kuhn, R.; Kunne, F.; Kurek, K.; Lauser, L.; Le Goff, J.M.; Lednev, A.A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Liska, T.; Maggiora, A.; Maggiora, M.; Magnon, A.; Mallot, G.K.; Mann, A.; Marchand, C.; Marroncle, J.; Martin, A.; Marzec, J.; Massmann, F.; Matsuda, T.; Maximov, A.N.; Meyer, W.; Michigami, T.; Mikhailov, Yu.V.; Moinester, M.A.; Mutter, A.; Nagaytsev, A.; Nagel, T.; Nassalski, J.; Negrini, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V.I.; Nunes, A.S.; Olshevsky, A.G.; Ostrick, M.; Padee, A.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Pawlukiewicz-Kaminska, B.; Perevalova, E.; Pesaro, G.; Peshekhonov, D.V.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V.A.; Pontecorvo, G.; Pretz, J.; Quintans, C.; Rajotte, J.F.; Ramos, S.; Rapatsky, V.; Reicherz, G.; Richter, A.; Robinet, F.; Rocco, E.; Rondio, E.; Ryabchikov, D.I.; Samoylenko, V.D.; Sandacz, A.; Santos, H.; Sapozhnikov, M.G.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schmitt, L.; Schluter, T.; Schopferer, S.; Schroder, W.; Shevchenko, O.Yu.; Siebert, H.W.; Silva, L.; Sinha, L.; Sissakian, A.N.; Slunecka, M.; Smirnov, G.I.; Sosio, S.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Sulej, R.; Takekawa, S.; Tessaro, S.; Tessarotto, F.; Teufel, A.; Tkatchev, L.G.; Uhl, S.; Uman, I.; Virius, M.; Vlassov, N.V.; Vossen, A.; Weitzel, Q.; Windmolders, R.; Wislicki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zhao, J.; Zhuravlev, N.; Zvyagin, A.
2010-01-01
The inclusive double-spin asymmetry, $A_{1}^{p}$, has been measured at COMPASS in deepinelastic polarised muon scattering off a large polarised NH3 target. The data, collected in the year 2007, cover the range Q2 > 1 (GeV/c)^2, 0.004 < x < 0.7 and improve the statistical precision of g_{1}^{p}(x) by a factor of two in the region x < 0.02. The new proton asymmetries are combined with those previously published for the deuteron to extract the non-singlet spin-dependent structure function g_1^NS(x,Q2). The isovector quark density, Delta_q_3(x,Q2), is evaluated from a NLO QCD fit of g_1^NS. The first moment of Delta_q3 is in good agreement with the value predicted by the Bjorken sum rule and corresponds to a ratio of the axial and vector coupling constants g_A/g_V = 1.28+-0.07(stat)+-0.10(syst).
The Spin Structure Function $g_1^{\\rm p}$ of the Proton and a Test of the Bjorken Sum Rule
Adolph, C.; Alexeev, M.G.; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anosov, V.; Austregesilo, A.; Azevedo, C.; Badelek, B.; Balestra, F.; Barth, J.; Baum, G.; Beck, R.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Birsa, R.; Bisplinghoff, J.; Bodlak, M.; Boer, M.; Bordalo, P.; Bradamante, F.; Braun, C.; Bressan, A.; Buchele, M.; Burtin, E.; Capozza, L.; Chang, W.C.; Chiosso, M.; Choi, I.; Chung, S.U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Duic, V.; Dziewiecki, M.; Efremov, A.; Eversheim, P.D.; Eyrich, W.; Ferrero, A.; Finger, M.; M. Finger jr; Fischer, H.; Franco, C.; von Hohenesche, N. du Fresne; Friedrich, J.M.; Frolov, V.; Fuchey, E.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Giordano, F.; Gnesi, I.; Gorzellik, M.; Grabmuller, S.; Grasso, A.; Grosse-Perdekamp, M.; Grube, B.; Grussenmeyer, T.; Guskov, A.; Haas, F.; Hahne, D.; von Harrach, D.; Hashimoto, R.; Heinsius, F.H.; Herrmann, F.; Hinterberger, F.; Horikawa, N.; d'Hose, N.; Hsieh, C.Yu; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jahn, R.; Jary, V.; Jorg, P.; Joosten, R.; Kabuss, E.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu. A.; Kisselev, Yu.; Klein, F.; Klimaszewski, K.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konigsmann, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.; Kramer, M.; Kremser, P.; Krinner, F.; Kroumchtein, Z.V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Lednev, A.A.; Lehmann, A.; Levillain, M.; Levorato, S.; Lichtenstadt, J.; Longo, R.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G.K.; Marchand, C.; Martin, A.; Marzec, J.; Matousek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Yu. V.; Miyachi, Y.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neyret, D.; Nikolaenko, V.I.; Novy, J.; Nowak, W.D.; Nunes, A.S.; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J.C.; Pereira, F.; Pesek, M.; Peshekhonov, D.V.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Rocco, E.; Rossiyskaya, N.S.; Ryabchikov, D.I.; Rychter, A.; Samoylenko, V.D.; Sandacz, A.; Santos, C.; Sarkar, S.; Savin, I.A.; Sbrizzai, G.; Schiavon, P.; Schmidt, K.; Schmieden, H.; Schonning, K.; Schopferer, S.; Selyunin, A.; Shevchenko, O.Yu.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sozzi, F.; Srnka, A.; Stolarski, M.; Sulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Takekawa, S.; Wolbeek, J. ter; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Tosello, F.; Tskhay, V.; Uhl, S.; Veloso, J.; Virius, M.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Ziembicki, M.; Zink, A.
2016-02-10
New results for the double spin asymmetry $A_1^{\\rm p}$ and the proton longitudinal spin structure function $g_1^{\\rm p}$ are presented. They were obtained by the COMPASS collaboration using polarised 200 GeV muons scattered off a longitudinally polarised NH$_3$ target. The data were collected in 2011 and complement those recorded in 2007 at 160\\,GeV, in particular at lower values of $x$. They improve the statistical precision of $g_1^{\\rm p}(x)$ by about a factor of two in the region $x\\lesssim 0.02$. A next-to-leading order QCD fit to the $g_1$ world data is performed. It leads to a new determination of the quark spin contribution to the nucleon spin, $\\Delta \\Sigma$ ranging from 0.26 to 0.36, and to a re-evaluation of the first moment of $g_1^{\\rm p}$. The uncertainty of $\\Delta \\Sigma$ is mostly due to the large uncertainty in the present determinations of the gluon helicity distribution. A new evaluation of the Bjorken sum rule based on the COMPASS results for the non-singlet structure function $g_1^{\\rm...
Precision calculation of threshold πd scattering, πN scattering lengths, and the GMO sum rule
Baru, V.; Hanhart, C.; Hoferichter, M.; Kubis, B.; Nogga, A.; Phillips, D. R.
2011-12-01
We use chiral perturbation theory (ChPT) to calculate the πd scattering length with an accuracy of a few percent, including isospin-violating corrections in both the two- and three-body sectors. In particular, we provide the technical details of a recent letter (Baru et al., 2011) [1], where we used data on pionic deuterium and pionic hydrogen atoms to extract the isoscalar and isovector pion-nucleon scattering lengths a and a. We study isospin-breaking contributions to the three-body part of a due to mass differences, isospin violation in the πN scattering lengths, and virtual photons. This last class of effects is ostensibly infrared enhanced due to the smallness of the deuteron binding energy. However, we show that the leading virtual-photon effects that might undergo such enhancement cancel, and hence the standard ChPT counting provides a reliable estimate of isospin violation in a due to virtual photons. Finally, we discuss the validity of the Goldberger-Miyazawa-Oehme sum rule in the presence of isospin violation, and use it to determine the charged-pion-nucleon coupling constant.
The Zb(10610) and Zb(10650) as axial-vector tetraquark states in the QCD sum rules
International Nuclear Information System (INIS)
Wang, Zhi-Gang; Huang, Tao
2014-01-01
In this article, we study the axial-vector mesons Z b (10610) and Z b (10650) with the Cγ μ –Cγ 5 type and Cγ μ –Cγ ν type interpolating currents, respectively, by carrying out the operator product expansion to the vacuum condensates up to dimension 10. In calculations, we explore the energy scale dependence of the QCD spectral densities of the hidden bottom tetraquark states in detail for the first time, and suggest a formula μ=√(M X/Y/Z 2 −(2M b ) 2 ) with the effective mass M b =5.13 GeV to determine the energy scales. The numerical results favor assigning the Z b (10610) and Z b (10650) as the Cγ μ –Cγ 5 type and Cγ μ –Cγ ν type hidden bottom tetraquark states, respectively. We obtain the mass of the J PC =1 ++ hidden bottom tetraquark state as a byproduct, which can be compared to the experimental data in the futures. Furthermore, we study the strong decays Z b ± (10610)→ϒπ ± ,η b ρ ± with the three-point QCD sum rules, the decay widths also support assigning the Z b (10610) as the Cγ μ –Cγ 5 type hidden bottom tetraquark state
Energy Technology Data Exchange (ETDEWEB)
Drangeid, K E; Sommerhalder, R [IBM Research Lab., Zurich (Switzerland)
1976-03-02
Based on previous work applying to normal conducting metals, an analog network model for superconducting metals is developed. The reciprocal surface impendance associated with this model is used as a response function in connection with the Kramers-Kronig relations and the sum rule to compute electrodynamic properties of superconductors.
International Nuclear Information System (INIS)
Nath, N.M.; Mukharjee, A.; Das, M.K.; Sarma, J.K.
2016-01-01
We present an analysis of the xF 3 (x,Q 2 ) structure function and Gross-Llewellyn Smith(GLS) sum rule taking into account the nuclear effects and higher twist correction. This analysis is based on the results presented in [N.M. Nath, et al, Indian J. Phys. 90 (2016) 117]. The corrections due to nuclear effects predicted in several earlier analysis are incorporated to our results of xF 3 (x,Q 2 ) structure function and GLS sum rule for free nucleon, corrected upto next-next-to-leading order (NNLO) perturbative order and calculate the nuclear structure function as well as sum rule for nuclei. In addition, by means of a simple model we have extracted the higher twist contributions to the non-singlet structure function xF 3 (x,Q 2 ) and GLS sum rule in NNLO perturbative orders and then incorporated them to our results. Our NNLO results along with nuclear effect and higher twist corrections are observed to be compatible with corresponding experimental data and other phenomenological analysis. (paper)
International Nuclear Information System (INIS)
Freericks, J. K.; Turkowski, V.
2009-01-01
Spectral moment sum rules are presented for the inhomogeneous many-body problem described by the fermionic Falicov-Kimball or Hubbard models. These local sum rules allow for arbitrary hoppings, site energies, and interactions. They can be employed to quantify the accuracy of numerical solutions to the inhomogeneous many-body problem such as strongly correlated multilayered devices, ultracold atoms in an optical lattice with a trap potential, strongly correlated systems that are disordered, or systems with nontrivial spatial ordering such as a charge-density wave or a spin-density wave. We also show how the spectral moment sum rules determine the asymptotic behavior of the Green function, self-energy, and dynamical mean field when applied to the dynamical mean-field theory solution of the many-body problem. In particular, we illustrate in detail how one can dramatically reduce the number of Matsubara frequencies needed to solve the Falicov-Kimball model while still retaining high precision, and we sketch how one can incorporate these results into Hirsch-Fye quantum Monte Carlo solvers for the Hubbard (or more complicated) models. Since the solution of inhomogeneous problems is significantly more time consuming than periodic systems, efficient use of these sum rules can provide a dramatic speed up in the computational time required to solve the many-body problem. We also discuss how these sum rules behave in nonequilibrium situations as well, where the Hamiltonian has explicit time dependence due to a driving field or due to the time-dependent change in a parameter such as the interaction strength or the origin of the trap potential.
International Nuclear Information System (INIS)
Shiles, E.; Sasaki, T.; Inokuti, M.; Smith, D.Y.
1980-01-01
An iterative, self-consistent procedure for the Kramers-Kronig analysis of data from reflectance, ellipsometric, transmission, and electron-energy-loss measurements is presented. This procedure has been developed for practical dispersion analysis since experimentally no single optical function can be readily measured over the entire range of frequencies as required by the Kramers-Kronig relations. The present technique is applied to metallic aluminum as an example. The results are then examined for internal consistency and for systematic errors by various optical sum rules. The present procedure affords a systematic means of preparing a self-consistent set of optical functions provided some optical or energy-loss data are available in all important spectral regions. The analysis of aluminum discloses that currently available data exhibit an excess oscillator strength, apparently in the vicinity of the L edge. A possible explanation is a systematic experimental error in the absorption-coefficient measurements resulting from surface layers: possibly oxides: present in thin-film transmission samples. A revised set of optical functions has been prepared by an ad hoc reduction of the reported absorption coefficient above the L edge by 14%. These revised data lead to a total oscillator strength consistent with the known electron density and are in agreement with dc-conductivity and stopping-power measurements as well as with absorption coefficients inferred from the cross sections of neighboring elements in the periodic table. The optical functions resulting from this study show evidence for both the redistribution of oscillator strength between energy levels and the effects on real transitions of the shielding of conduction electrons by virtual processes in the core states
Final COMPASS results on the deuteron spin-dependent structure function g1d and the Bjorken sum rule
Directory of Open Access Journals (Sweden)
C. Adolph
2017-06-01
Full Text Available Final results are presented from the inclusive measurement of deep-inelastic polarised-muon scattering on longitudinally polarised deuterons using a 6LiD target. The data were taken at 160 GeV beam energy and the results are shown for the kinematic range 1(GeV/c24GeV/c2 in the mass of the hadronic final state. The deuteron double-spin asymmetry A1d and the deuteron longitudinal-spin structure function g1d are presented in bins of x and Q2. Towards lowest accessible values of x, g1d decreases and becomes consistent with zero within uncertainties. The presented final g1d values together with the recently published final g1p values of COMPASS are used to again evaluate the Bjorken sum rule and perform the QCD fit to the g1 world data at next-to-leading order of the strong coupling constant. In both cases, changes in central values of the resulting numbers are well within statistical uncertainties. The flavour-singlet axial charge a0, which is identified in the MS‾ renormalisation scheme with the total contribution of quark helicities to the nucleon spin, is extracted at next-to-leading order accuracy from only the COMPASS deuteron data: a0(Q2=3(GeV/c2=0.32±0.02stat±0.04syst±0.05evol. Together with the recent results on the proton spin structure function g1p, the results on g1d constitute the COMPASS legacy on the measurements of g1 through inclusive spin-dependent deep inelastic scattering.
Local-duality QCD sum rules for strong isospin breaking in the decay constants of heavy-light mesons
Energy Technology Data Exchange (ETDEWEB)
Lucha, Wolfgang [Austrian Academy of Sciences, Institute for High Energy Physics, Vienna (Austria); Melikhov, Dmitri [Austrian Academy of Sciences, Institute for High Energy Physics, Vienna (Austria); M.V. Lomonosov Moscow State University, D.V. Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); University of Vienna, Faculty of Physics, Vienna (Austria); Simula, Silvano [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, Rome (Italy)
2018-02-15
We discuss the leptonic decay constants of heavy-light mesons by means of Borel QCD sum rules in the local-duality (LD) limit of infinitely large Borel mass parameter. In this limit, for an appropriate choice of the invariant structures in the QCD correlation functions, all vacuum-condensate contributions vanish and all nonperturbative effects are contained in only one quantity, the effective threshold. We study properties of the LD effective thresholds in the limits of large heavy-quark mass m{sub Q} and small light-quark mass m{sub q}. In the heavy-quark limit, we clarify the role played by the radiative corrections in the effective threshold for reproducing the pQCD expansion of the decay constants of pseudoscalar and vector mesons. We show that the dependence of the meson decay constants on m{sub q} arises predominantly (at the level of 70-80%) from the calculable m{sub q}-dependence of the perturbative spectral densities. Making use of the lattice QCD results for the decay constants of nonstrange and strange pseudoscalar and vector heavy mesons, we obtain solid predictions for the decay constants of heavy-light mesons as functions of m{sub q} in the range from a few to 100 MeV and evaluate the corresponding strong isospin-breaking effects: f{sub D{sup +}} - f{sub D{sup 0}} = (0.96 ± 0.09) MeV, f{sub D}{sup {sub *}{sub +}} - f{sub D}{sup {sub *}{sub 0}} = (1.18 ± 0.35) MeV, f{sub B{sup 0}} - f{sub B{sup +}} = (1.01 ± 0.10) MeV, f{sub B}{sup {sub *}{sub 0}} - f{sub B}{sup {sub *}{sub +}} = (0.89 ± 0.30) MeV. (orig.)
Alabdulmohsin, Ibrahim M.
2018-01-01
In this chapter, we extend the previous results of Chap. 2 to the more general case of composite finite sums. We describe what composite finite sums are and how their analysis can be reduced to the analysis of simple finite sums using the chain rule. We apply these techniques, next, on numerical integration and on some identities of Ramanujan.
Alabdulmohsin, Ibrahim M.
2018-03-07
In this chapter, we extend the previous results of Chap. 2 to the more general case of composite finite sums. We describe what composite finite sums are and how their analysis can be reduced to the analysis of simple finite sums using the chain rule. We apply these techniques, next, on numerical integration and on some identities of Ramanujan.
Photonuclear data index 1986-1990
Energy Technology Data Exchange (ETDEWEB)
Varlamov, V A; Stepanov, M E; Sapunenko, V V [Moscow State University, Institute of Nuclear Physics, Centre for Photonuclear Experimental Data, Moscow (Russian Federation)
1992-07-01
This issue presents a bibliographic index to experimental photonuclear data published in periodical scientific literature during the years 1986-1990. The main tabulation is sorted by nucleus and reaction. It is supplemented by a reference index, an author index, explanatory tables of terms and abbreviations used, and a table of isotopic abundances and nucleon separation energies. The index is in English with an introduction in Russian and English. (author)
International Nuclear Information System (INIS)
Kohno, M.
1983-01-01
We report fully consistent calculations of the longitudinal and transverse response functions of the inclusive quasi-elastic electron scattering on 12 C in the Hartree-Fock approximation. The distorted wave for the outgoing nucleon is constructed from the same non-local Hartree-Fock field as in the ground-state description. Thus the orthogonality and Pauli principle requirements are naturally satisfied. The theoretical prediction, based on the standard density-dependent effective interaction (GO force), shows a good correspondence to the experimental data. Since the calculated response functions automatically satisfy the relevant sum rule, this work illuminates the well-known puzzle concerning the longitudinal part, which remains to be solved. We study the energy-weighted sum rules and discuss effects beyond the mean-field approximation. Meson-exchange-current contributions to the transverse response function are also estimated and found to be small due to cancellations among them. (orig.)
International Nuclear Information System (INIS)
Oi, T.; Ishida, T.
1984-01-01
The approximation methods for the zero-point energy (ZPE) previously developed using the Lanczo's tau method have been applied to the shifts in ZPE due to hydrogen isotope substitutions. Six types of approximation methods have been compared and analyzed on the basis of a weighing function Ω(lambda) varies as lambda/sup k/ and the actual eigenvalue shift spectra. The method generated by the most general optimzation treatment yields a predictable and generally satisfactory precision of the order of 1% or better. A linear frequency sum rule has been derived, which approximately holds for the sets of isotopic molecules which satisfy the second-order frequency sum rule. 19 references, 3 figures, 3 tables
International Nuclear Information System (INIS)
Sidorov, A.V.; Tokarev, M.V.
1997-01-01
A detailed NNLO QCD analysis of new CCFR data on xF 3 structure function including the target mass, higher twist and nuclear corrections was performed and parametrizations of the perturbative and power terms of the structure function were constructed. The results of QDC analysis of the structure function were used to study the Q 2 -dependence of the Gross-Llewellyn-Smith sum rule. The α s /π-expansion of S GLS (Q 2 ) was studied and parameters of the expansion were found to be s 1 =2.74±0.01, s 2 =-2.22±0.23, s 3 =-7.86±1.74 which are in good agreement with the perturbative QCD predictions for the Gross-Llewellyn-Smith sum rule in the next-to-leading and next-to-next-leading order
International Nuclear Information System (INIS)
Sidorov, A.V.; Tokarev, M.V.
1997-01-01
A detailed NNLO QCD analysis of new CCFR data on xF 3 structure function including the target mass, higher twist and nuclear corrections was performed and parametrizations of the perturbative and power terms of the structure function were constructed. The results of QCD analysis of the structure function were used to study the Q 2 -dependence of the Gross-Llewellyn Smith sum rule. The α S /π-expansion of S GLS (Q 2 ) was studied and parameters of the expansion were found to be s 1 =2.74±0.01, s 2 =-2.22±0.23, s 3 =-7.86±1.74 which are in good agreement with the perturbative QCD predictions for the Gross-Llewellyn Smith sum rule in the next-to-leading and next-to-next-to-leading order
Energy Technology Data Exchange (ETDEWEB)
Hilger, Thomas Uwe
2012-04-11
The interplay of hadron properties and their modification in an ambient nuclear medium on the one hand and spontaneous chiral symmetry breaking and its restoration on the other hand is investigated. QCD sum rules for D and B mesons embedded in cold nuclear matter are evaluated. We quantify the mass splitting of D- anti D and B- anti B mesons as a function of the nuclear matter density and investigate the impact of various condensates in linear density approximation. The analysis also includes D{sub s} and D{sup *}{sub 0} mesons. QCD sum rules for chiral partners in the open-charm meson sector are presented at nonzero baryon net density or temperature. We focus on the differences between pseudo-scalar and scalar as well as vector and axial-vector D mesons and derive the corresponding Weinberg type sum rules. Based on QCD sum rules we explore the consequences of a scenario for the ρ meson, where the chiral symmetry breaking condensates are set to zero whereas the chirally symmetric condensates remain at their vacuum values. The complementarity of mass shift and broadening is discussed. An alternative approach which utilizes coupled Dyson-Schwinger and Bethe-Salpeter equations for quark-antiquark bound states is investigated. For this purpose we analyze the analytic structure of the quark propagators in the complex plane numerically and test the possibility to widen the applicability of the method to the sector of heavy-light mesons in the scalar and pseudo-scalar channels, such as the D mesons, by varying the momentum partitioning parameter. The solutions of the Dyson-Schwinger equation in the Wigner-Weyl phase of chiral symmetry at nonzero bare quark masses are used to investigate a scenario with explicit but without dynamical chiral symmetry breaking.
Wang, Hongxin; Friedrich, Stephan; Li, Lei; Mao, Ziliang; Ge, Pinghua; Balasubramanian, Mahalingam; Patil, Daulat S
2018-03-28
According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d 10 → 3d 0 . In addition, extremely dilute (edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d 0 to a closed shell 3d 10 ; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L 3 and post-L 2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.
Energy Technology Data Exchange (ETDEWEB)
Klopot, Yaroslav, E-mail: klopot@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Oganesian, Armen, E-mail: armen@itep.ru [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute of Theoretical and Experimental Physics, 117218 Moscow (Russian Federation); Teryaev, Oleg, E-mail: teryaev@theor.jinr.ru [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)
2013-12-15
We studied the applications of the anomaly sum rule (ASR) to the transition form factors of light pseudoscalar mesons: π{sup 0},η and η{sup ′}. This nonperturbative QCD approach can be used even if the QCD factorization is broken. The status of possible small non-OPE corrections to continuum in comparison to BaBar and Belle data is explored. The accuracy of the applied method and the role of the quark mass contributions are discussed.
Zhao, Yumin
1997-07-01
By the techniques of the Wick theorem for coupled clusters, the no-energy-weighted electromagnetic sum-rule calculations are presented in the sdg neutron-proton interacting boson model, the nuclear pair shell model and the fermion-dynamical symmetry model. The project supported by Development Project Foundation of China, National Natural Science Foundation of China, Doctoral Education Fund of National Education Committee, Fundamental Research Fund of Southeast University
International Nuclear Information System (INIS)
Ahmed, M. W.; Blackston, M. A.; Perdue, B. A.; Tornow, W.; Weller, H. R.; Norum, B.; Sawatzky, B.; Prior, R. M.; Spraker, M. C.
2008-01-01
It is shown that a measurement of the analyzing power obtained with linearly polarized γ-rays and an unpolarized target can provide an indirect determination of two physical quantities. These are the Gerasimov-Drell-Hearn (GDH) sum rule integrand for the deuteron and the sum rule integrand for the forward spin polarizability (γ 0 ) near photodisintegration threshold. An analysis of data for the d(γ-vector,n)p reaction and other experiments is presented. A fit to the world data analyzed in this manner gives a GDH integral value of -603±43μb between the photodisintegration threshold and 6 MeV. This result is the first confirmation of the large contribution of the 1 S 0 (M1) transition predicted for the deuteron near photodisintegration threshold. In addition, a sum rule value of 3.75±0.18 fm 4 for γ 0 is obtained between photodisintegration threshold and 6 MeV. This is a first indirect confirmation of the leading-order effective field theory prediction for the forward spin-polarizability of the deuteron
Updated Photonuclear Data Library and Database for Photon Strength Functions
Directory of Open Access Journals (Sweden)
Dimitriou Paraskevi
2015-01-01
Full Text Available Photonuclear cross sections and gamma-ray data used to extract Photon Strength Functions are important for a large range of applications including basic sciences. The recommendations of an IAEA Consultant’s Meeting to update the IAEA Photonuclear Data Library and create a Reference Database for Photon Strength Functions are presented.
Laser induced photonuclear and fusion-reactions
International Nuclear Information System (INIS)
LoDato, V.A.
1977-01-01
The energy release from the fusion-fission pellets is demonstrated. It is shown that the coupling of the fusion-fission process is extremely efficient provided one can obtain the proper compression heating. The pellet of an outer core of (Li6D-Li6T) with an inner core of U238 is shown to be an efficient and practical fuel and can be ignited by the present generation of lasers to produce thermonuclear burn. The demonstration of the efficiency for photonuclear and photofission pellets is shown. However no suitable gamma ray source exists at present to initiate these processes. (orig.) [de
Bibliographic index to photonuclear reaction data
International Nuclear Information System (INIS)
Asami, Tetsuo; Nakagawa, Tsuneo.
1993-10-01
This report contains the bibliographic index data on photonuclear reactions and on their inverse ones, in the format similar to CINDA for neutron nuclear data. As photonuclear reactions the electron-induced reaction data are also included. As the inverse reactions considered are those induced by neutron, proton, deuteron, triton, helion and alpha particles. The index covers major journals on nuclear data published in 1995 to 1992, for all nuclides through hydrogen (H) to einsteinium (Es). The bibliographic index contains information on target nucleus, incident beam, type of reaction and quantity, energy range of incident beam, laboratory, type of work, reference citations, first author's name, and short comment. The index also contains the indication for information on cross-section data. All the index data are listed in the order of target element, target, mass and incident particle, and in the chronological order of reference data. Also a brief description is given on the data format, the abbreviations used and the journals surveyed. (author)
QCD sum rules of the Laplace transform type for the gluon component of the U(1)sub(A) meson mass
International Nuclear Information System (INIS)
Narison, S.
1981-07-01
We get upper bound of the gluon component of the U(1)sub(A) meson mass using QCD sum rules of the Laplace transform type to the two-point functions associated to the divergence of the U(1)sub(A) current in the chiral limit. For Λ is approximately equal to 70 is approximately 210 MeV and fsub(eta') is approximately equal to (0.5 is approximately 0.7) sqrt 3 fsub(π), we obtain Msub(G) is approximately smaller to (0.6 is approximately 0.85) GeV, which indicates an important gluon contribution to the eta' mass. (author)
Energy Technology Data Exchange (ETDEWEB)
Mannel, T. [Siegen Univ. (Germany). FB 7, Theoretische Physik; Pecjak, B.D. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Pivovarov, A.A. [Siegen Univ. (Germany). FB 7, Theoretische Physik]|[Russian Academy of Sciecnes, Moscow (Russian Federation). Inst. for Nuclear Research
2007-03-15
We use QCD sum rules to compute matrix elements of the {delta}B=2 operators appearing in the heavy-quark expansion of the width difference of the B{sub s} mass eigenstates. Our analysis includes the leading-order operators Q and Q{sub S}, as well as the subleading operators R{sub 2} and R{sub 3}, which appear at next-to-leading order in the 1/m{sub b} expansion. We conclude that the violation of the factorization approximation for these matrix elements due to non-perturbative vacuum condensates is as low as 1-2%. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Wang, Feng; Chen, Junlong; Liu, Jueping, E-mail: jpliu@whu.edu.cn [Department of Physics, School of Physics Science and Technology, Wuhan University, 430072, Wuhan (China)
2015-09-28
Based on a correction from instanton–gluon interference to the correlation function, the properties of the 0{sup -+} pseudoscalar glueball are investigated in a family of finite-width Gaussian sum rules. In the framework of a semiclassical expansion for quantum chromodynamics in the instanton liquid background, the contribution arising from the interference between instantons and the quantum gluon fields is calculated, and it is included in the correlation function together with a pure-classical contribution from instantons and the perturbative one. The interference contribution turns out to be gauge-invariant, to be free from an infrared divergence, and to have a great role to play in restoring the positivity of the spectra of the full correlation function. The negligible contribution from vacuum condensates is excluded in our correlation function to avoid double counting. Instead of the usual zero-width approximation for the resonances, the usual Breit–Wigner form with a suitable threshold behavior for the spectral function of the finite-width resonances is adopted. Consistency between the subtracted and unsubtracted sum rules is very well justified. The values of the mass, decay width, and coupling constants for the 0{sup -+} resonance in which the glueball fraction is dominant are obtained, and they agree with the phenomenological analysis.
Energy Technology Data Exchange (ETDEWEB)
Wang, Feng; Chen, Junlong; Liu, Jueping [Wuhan University, Department of Physics, School of Physics Science and Technology, Wuhan (China)
2015-09-15
Based on a correction from instanton-gluon interference to the correlation function, the properties of the 0{sup -+} pseudoscalar glueball are investigated in a family of finite-width Gaussian sum rules. In the framework of a semiclassical expansion for quantum chromodynamics in the instanton liquid background, the contribution arising from the interference between instantons and the quantum gluon fields is calculated, and it is included in the correlation function together with a pure-classical contribution from instantons and the perturbative one. The interference contribution turns out to be gauge-invariant, to be free from an infrared divergence, and to have a great role to play in restoring the positivity of the spectra of the full correlation function. The negligible contribution from vacuum condensates is excluded in our correlation function to avoid double counting. Instead of the usual zero-width approximation for the resonances, the usual Breit-Wigner form with a suitable threshold behavior for the spectral function of the finite-width resonances is adopted. Consistency between the subtracted and unsubtracted sum rules is very well justified. The values of the mass, decay width, and coupling constants for the 0{sup -+} resonance in which the glueball fraction is dominant are obtained, and they agree with the phenomenological analysis. (orig.)
Cvetič, Gorazd; Kataev, A. L.
2016-07-01
We consider a new form of analytical perturbation theory expansion in the massless S U (Nc) theory, for the nonsinglet part of the e+e--annihilation to hadrons Adler function Dn s and of the Bjorken sum rule of the polarized lepton-hadron deep-inelastic scattering Cns B j p, and demonstrate its validity at the O (αs4)-level at least. It is a two-fold series in powers of the conformal anomaly and of S U (Nc) coupling αs. Explicit expressions are obtained for the {β }-expanded perturbation coefficients at O (αs4) level in MS ¯ scheme, for both considered physical quantities. Comparisons of the terms in the {β }-expanded coefficients are made with the corresponding terms obtained by using extra gluino degrees of freedom, or skeleton-motivated expansion, or Rδ-scheme motivated expansion in the Principle of Maximal Conformality. Relations between terms of the {β }-expansion for the Dn s- and Cns B j p-functions, which follow from the conformal symmetry limit and its violation, are presented. The relevance to the possible new analyses of the experimental data for the Adler function and Bjorken sum rule is discussed.
The NIRA computer program package (photonuclear data center). Final report
International Nuclear Information System (INIS)
Vander Molen, H.J.; Gerstenberg, H.M.
1976-02-01
The Photonuclear Data Center's NIRA library of programs, executable from mass storage on the National Bureau of Standard's central computer facility, is described. Detailed instructions are given (with examples) for the use of the library to analyze, evaluate, synthesize, and produce for publication camera-ready tabular and graphical presentations of digital photonuclear reaction cross-section data. NIRA is the acronym for Nuclear Information Research Associate
Bibliographic index to photonuclear reaction data (1955--1992)
Energy Technology Data Exchange (ETDEWEB)
Asami, Tetsuo [Data Engineering, Inc., Yokohama (Japan); Nakagawa, Tsuneo [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Dept. of Reactor Engineering
1993-10-01
Japanese Nuclear Data Committee (JNDC) has a plan to compile the evaluated data library for photon-induced nuclear reaction cross sections, and the work on the data evaluation is in progress at the present. In the evaluations for these data a bibliographic index for neutron nuclear data is required. As the bibliographic index to photonuclear reactions, several excellent compilations have been done at some research institutes in the world, and have contributed to various basic and applied researches on the photonuclear reactions. For example, there are the abstract sheets published by US National Bureau of Standards and the data index published regularly in Russia. On the other hand, the four-center network on nuclear data (US National Nuclear Data Center at Brookhaven, Russian Nuclear Data Center at Obninsk, NEA Data Bank at Paris and IAEA Nuclear Data Section at Vienna) compiles and exchanges the numerical data on photonuclear reactions as well as on neutron-induced ones, in the EXFOR format. Those numerical data are available for users. There is, however, no bibliographic index to photonuclear reactions, available for general users. Therefore, the present work to make a photonuclear reaction data index has been done urgently to contribute to the above-mentioned data evaluation. Although these data might be still incomplete and have some defects, we have decided to serve this as the first edition of our photonuclear reaction index.
International Nuclear Information System (INIS)
Kota, V.K.B.
1991-01-01
In the interacting boson-fermion model of collective nuclei, in the symmetry limits of the model appropriate for vibrational, rotational and γ-unstable nuclei, for one-particle transfer, the selection rules, model predictions for the allowed strengths and comparison of theory with experiment are briefly reviewed. In the spectral-averaging theory, with the specific example of orbit occupancies, the smoothed forms (linear or better ratio of Gaussians) as determined by central limit theorems, how they provide a good criterion for selecting effective interactions and the convolution structure of occupancy densities in huge spaces are described. Complementary information provided by nuclear models and statistical laws is broughtout. (author). 63 refs., 5 figs
Energy Technology Data Exchange (ETDEWEB)
Jeffries, J R; Moore, K T; Butch, N P; Maple, M B
2010-05-19
We examine the degree of 5f electron localization in URu{sub 2}Si{sub 2} using spin-orbit sum rule analysis of the U N{sub 4,5} (4d {yields} 5f) edge. When compared to {alpha}-U metal, US, USe, and UTe, which have increasing localization of the 5f states, we find that the 5f states of URu{sub 2}Si{sub 2} are more localized, although not entirely. Spin-orbit analysis shows that intermediate coupling is the correct angular momentum coupling mechanism for URu{sub 2}Si{sub 2} when the 5f electron count is between 2.6 and 2.8. These results have direct ramifications for theoretical assessment of the hidden order state of URu{sub 2}Si{sub 2}, where the degree of localization of the 5f electrons and their contribution to the Fermi surface are critical.
International Nuclear Information System (INIS)
Barabash, L.S.; Baranov, S.A.; Batusov, Yu.A.
1996-01-01
The isoscalar structure functions xF 3 and F 2 are measured as functions of x averaged over all Q 2 permissible for the range 6 to 28 GeV of incident (anti)neutrino energy. With the measured values of xF 3 , the value of the Gross-Llewellyn Smith sum rule is found to be ∫ 0 1 F 3 dx=2.13±0.38 (stat)±0.26 (syst). The QCD analysis of xF 3 provides Λ b ar M b ar S bar =358±59 MeV. The obtained value of the strong interaction constant α S (M Z )=0.120 -4 +3 is larger than most of the deep inelastic scattering results. 37 refs., 1 figs., 3 tabs
Analysis of the strong coupling form factors of ΣbNB and ΣcND in QCD sum rules
Yu, Guo-Liang; Wang, Zhi-Gang; Li, Zhen-Yu
2017-08-01
In this article, we study the strong interaction of the vertices Σ b NB and Σ c ND using the three-point QCD sum rules under two different Dirac structures. Considering the contributions of the vacuum condensates up to dimension 5 in the operation product expansion, the form factors of these vertices are calculated. Then, we fit the form factors into analytical functions and extrapolate them into time-like regions, which gives the coupling constants. Our analysis indicates that the coupling constants for these two vertices are G ΣbNB = 0.43±0.01 GeV-1 and G ΣcND = 3.76±0.05 GeV-1. Supported by Fundamental Research Funds for the Central Universities (2016MS133)
Analysis of the strong decay X(5568) → B{sub s}{sup 0}π{sup +} with QCD sum rules
Energy Technology Data Exchange (ETDEWEB)
Wang, Zhi-Gang [North China Electric Power University, Department of Physics, Baoding (China)
2016-05-15
In this article, we take the X(5568) to be the scalar diquark-antidiquark type tetraquark state, study the hadronic coupling constant g{sub XB{sub sπ}} with the three-point QCD sum rules by carrying out the operator product expansion up to the vacuum condensates of dimension-6 and including both the connected and the disconnected Feynman diagrams; then we calculate the partial decay width of the strong decay X(5568) → B{sub s}{sup 0}π{sup +} and obtain the value Γ{sub X} = (20.5 ± 8.1) MeV, which is consistent with the experimental data Γ{sub X} = (21.9 ± 6.4{sup +5.0}{sub -2.5}) MeV from the D0 collaboration. (orig.)
Photonuclear reactions triggered by lightning discharge.
Enoto, Teruaki; Wada, Yuuki; Furuta, Yoshihiro; Nakazawa, Kazuhiro; Yuasa, Takayuki; Okuda, Kazufumi; Makishima, Kazuo; Sato, Mitsuteru; Sato, Yousuke; Nakano, Toshio; Umemoto, Daigo; Tsuchiya, Harufumi
2017-11-22
Lightning and thunderclouds are natural particle accelerators. Avalanches of relativistic runaway electrons, which develop in electric fields within thunderclouds, emit bremsstrahlung γ-rays. These γ-rays have been detected by ground-based observatories, by airborne detectors and as terrestrial γ-ray flashes from space. The energy of the γ-rays is sufficiently high that they can trigger atmospheric photonuclear reactions that produce neutrons and eventually positrons via β + decay of the unstable radioactive isotopes, most notably 13 N, which is generated via 14 N + γ → 13 N + n, where γ denotes a photon and n a neutron. However, this reaction has hitherto not been observed conclusively, despite increasing observational evidence of neutrons and positrons that are presumably derived from such reactions. Here we report ground-based observations of neutron and positron signals after lightning. During a thunderstorm on 6 February 2017 in Japan, a γ-ray flash with a duration of less than one millisecond was detected at our monitoring sites 0.5-1.7 kilometres away from the lightning. The subsequent γ-ray afterglow subsided quickly, with an exponential decay constant of 40-60 milliseconds, and was followed by prolonged line emission at about 0.511 megaelectronvolts, which lasted for a minute. The observed decay timescale and spectral cutoff at about 10 megaelectronvolts of the γ-ray afterglow are well explained by de-excitation γ-rays from nuclei excited by neutron capture. The centre energy of the prolonged line emission corresponds to electron-positron annihilation, providing conclusive evidence of positrons being produced after the lightning.
International Nuclear Information System (INIS)
Kaschner, R.; Ziesche, P.
1986-07-01
Hellmann-Feynman theorems for partially extended arrangements of atoms (chains, strips, layers, wires and slabs) are derived and applied to one-, two-, and three-dimensional solids. The derivatives of the bulk energy with respect to the lattice spacings are related to the Hellmann-Feynman forces in the corresponding semi-infinite unrelaxed solids. These forces have to alternate going from the surface into the bulk provided that the latter is in equilibrium. (author)
International Nuclear Information System (INIS)
Burkardt, M.
2013-01-01
Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum due to final state interactions as it leaves the target in a DIS experiment.
International Nuclear Information System (INIS)
Wang, Zhi-Gang
2014-01-01
In this article, we calculate the contributions of the vacuum condensates up to dimension 10 in the operator product expansion, and study the J PC = 0 ++ , 1 +- , 2 ++ D * anti D * , D s * anti D s * , B * anti B * , B s * anti B s * molecular states with the QCD sum rules. In the calculations, we use the formula μ = √(M 2 X/Y/Z -(2M Q ) 2 ) to determine the energy scales of the QCD spectral densities. The numerical results favor assigning the Z c (4020) and Z c (4025) to the J PC = 0 ++ , 1 +- or 2 ++ D * anti D * molecular states, the Y(4140) to the J PC = 0 ++ D s * anti D s * molecular state, the Z b (10650) to the J PC = 1 +- B * anti B * molecular state, and they disfavor assigning the Y(3940) to the (J PC = 0 ++ ) molecular state. The present predictions can be confronted with the experimental data in the future. (orig.)
The Saskatchewan-Alberta large acceptance detector for photonuclear physics
Cairns, E. B.; Cameron, J.; Choi, W. C.; Fielding, H. W.; Green, P. W.; Greeniaus, L. G.; Hackett, E. D.; Holm, L.; Kolb, N. R.; Korkmaz, E.; Langill, P. P.; McDonald, W. J.; Mack, D.; Olsen, W. C.; Peterson, B. A.; Rodning, N. L.; Soukup, J.; Zhu, J.; Hutcheon, D.; Caplan, H. S.; Pywell, R. E.; Skopik, D. M.; Vogt, J. M.; van Heerden, I. J.
1992-09-01
The Saskatchewan-Alberta Large Acceptance Detector (SALAD) is a 4 π detector designed and built for studies of photonuclear reactions with a tagged photon beam. The design and performance of the detector are described. Its characteristics have been studied by examining p-p elastic scattering with a proton beam at TRIUMF.
Nucleosynthesis of heavy elements by the photonuclear reaction
International Nuclear Information System (INIS)
Hayakawa, Takehito
2002-01-01
Nucleosynthesis of heavy elements is important for understanding of the site mechanism in the stellar and cosmochronology. The nuclei heavier than iron have been synthesized mainly by the s-process and the β-decay after the r-process. The light isotope p-nuclei produced by the photonuclear reaction in Type II supernovae explosions. In order to understand the role of each process, the ratios of the processes are calculated. I propose the experimental plan using the photon sources. (author)
Application of a Betatron in Photonuclear Activation Analysis
Energy Technology Data Exchange (ETDEWEB)
Brune, D [AB Atomenergi, Nykoeping (Sweden); Mattsson, K; Liden, K [Dept . of Radiation Physics, Univ. of Lund (Sweden)
1968-08-15
The present study concerns the determination of fluorine, iodine, lead and mercury by means of photonuclear activation technique using a betatron. The detection limit obtained for the elements in the above given sequence amounted to 3, 50, 400 and 15 {mu}g respectively. The technique has been applied in the determination of iodine in pharmaceuticals. A rotating sample holder device was inserted in the Bremsstrahlung beam of the betatron in order to ensure uniform irradiation of the samples.
International Nuclear Information System (INIS)
Radyushkin, A.V.; Ruskov, R.
1992-01-01
We extend the QCD sum rule analysis of the form factor F γ* γ *→π 0 (q 1 2 ,q 2 2 ) into the region of small virtuality of one of the photons, where one should perform more precisely an OPE to factorize large and small distance contributions. As a first step the form factor is investigated in the region of moderate virtualities and the full corrections in the sum rule are obtained. It is shown that the infrared mass singularities are subtracted in the corresponding OPE for essentially nonsymmetric kinematics due to the operators of lowest two twists. On a simple scalar example the most important steps of the further calculations are demonstrated. 26 refs.; 8 figs
International Nuclear Information System (INIS)
Jackson, A.D.; Weiss, C.; Wirzba, A.
1990-01-01
The Skyrme model has the same high density behavior as a free quark gas. However, the inclusion of higher-order terms spoils this agreement. We consider the all-order sum of a class of chiral invariant Lagrangians of even order in L μ suggested by Marleau. We prove Marleau's conjecture that these terms are of second order in the derivatives of the chiral angle for the hedgehog case and show the terms are unique under the additional condition that, for each order, the identity map on the 3-sphere S 3 (L) is a solution. The general form of the summation can be restricted by physical constraints leading to stable results. Under the assumption that the Lagrangian scales like the non-linear sigma model at low densities and like the free quark gas at high densities, we prove that a chiral phase transition must occur. (orig.)
Photoneutron and Photonuclear Cross Sections According to Packed cluster Model
International Nuclear Information System (INIS)
El-Mekkawi, L.S.; El-Bakty, O.M.
1998-01-01
Photonuclear gross sections have been estimated for 232 Th, 237 Np, 239 Pu, 233 U, 234 U, 235 U, 238 U in the energy range from threshold up to 20 MeV, by perturbation balance in Packed Cluster. The Packed Cluster (gamma, f) and (gamma, n) cross sections require complete absence of any (gamma,2n) or (gamma,nf) cross sections for 233 U and 234 U as in experiment. It also explains the early (gamma,n) and gamma,nf) reactions in 235 U
Electro- and photonuclear physics with polarized beams and targets
International Nuclear Information System (INIS)
Holt, R.J.
1987-01-01
Two long-standing issues in photonuclear physics, the giant M1 resonance in Pb and deuteron photodisintegration, have been studied recently with polarized photons at Urbana and Frascati, respectively. The implications that this work has for settling these key issues will be discussed. In addition, the advantages of the internal polarized target method for electron scattering studies will be discussed and the technology of internal polarized target development will be reviewed. The first results from a spin-exchange, optically-pumped polarized H and D source will be presented
Photonuclear reactions in the Δ-resonance region
International Nuclear Information System (INIS)
Arends, J.
1988-02-01
The following review is intended to give an overview of the experimental information on photon-induced reactions in comparison with theoretical calculations. Most of the experimental data presented here, were measured at the Bonn 500 MeV synchrotron. In section II the experimental techniques used for the measurements are briefly described. Section III deals with the most inclusive information, the total hadronic photoabsorption cross section. In sections IV and V, pion production and proton emission channels are discussed. A brief outlook to prospects for future photonuclear experiments at the new electron stretcher ELSA is given in section VI. (orig./HSI)
International Nuclear Information System (INIS)
Eletsky, V.L.; Ioffe, B.L.
1993-01-01
The recent experimental data on D +- D0 and D *+- D*0 mass differences are used as inputs in the QCD sum rules to obtain new estimates on the mass difference of light quarks and on the difference of their condensates: m d -m u =3±1 MeV, left-angle bar dd right-angle -left-angle bar uu right-angle=-(2.5±1)x10 -3 left-angle bar uu right-angle (at a standard normalization point, μ=0.5 GeV)
Alabdulmohsin, Ibrahim M.
2018-03-07
In this chapter, we use the theory of summability of divergent series, presented earlier in Chap. 4, to derive the analogs of the Euler-Maclaurin summation formula for oscillating sums. These formulas will, in turn, be used to perform many remarkable deeds with ease. For instance, they can be used to derive analytic expressions for summable divergent series, obtain asymptotic expressions of oscillating series, and even accelerate the convergence of series by several orders of magnitude. Moreover, we will prove the notable fact that, as far as the foundational rules of summability calculus are concerned, summable divergent series behave exactly as if they were convergent.
Alabdulmohsin, Ibrahim M.
2018-01-01
In this chapter, we use the theory of summability of divergent series, presented earlier in Chap. 4, to derive the analogs of the Euler-Maclaurin summation formula for oscillating sums. These formulas will, in turn, be used to perform many remarkable deeds with ease. For instance, they can be used to derive analytic expressions for summable divergent series, obtain asymptotic expressions of oscillating series, and even accelerate the convergence of series by several orders of magnitude. Moreover, we will prove the notable fact that, as far as the foundational rules of summability calculus are concerned, summable divergent series behave exactly as if they were convergent.
Photonuclear excitation of 103Rh by synchrotron radiation
International Nuclear Information System (INIS)
Yoshihara, Kenji; Kaji, Harumi; Sekine, Tsutomu; Mukoyama, Takeshi
1989-01-01
Photonuclear excitation of the 103 Rh nucleus was studied using synchrotron radiation. Formation of the excited state was confirmed by observing K X-rays emitted following the isomeric transition of the 103m Rh with a low-energy photon spectrometer. The intensity of induced activity due to 103 Rh(γ,γ') 103m Rh reaction was determined carefully by subtracting the fluorescent K X-rays due to natural background radiation. The integral cross-section for isomer production of 103m Rh by resonance absorption of photons at 295 keV is found to be (2.1±0.8) x 10 -28 cm 2 eV and is compared with that estimated from the previous experimental value for the 1277-keV level. (author)
Photonuclear excitation of 103Rh by synchrotron radiation
International Nuclear Information System (INIS)
Kaji, Harumi; Yoshihara, Kenji; Mukoyama, Takeshi; Nakajima, Tetsuo
1989-01-01
Photonuclear excitation of 103 Rh nucleus was studied by the use of synchrotron radiation at KEK. Formation of excited state was confirmed by observing Rh K X-rays emitted following the isomeric transition of 103m Rh with a low-energy photon spectrometer. The induced activity due to 103 Rh(γ,γ') 103m Rh reaction was determined carefully by subtracting the fluorescent K X-rays due to natural background radiation. The integral cross-section for 103m Rh by resonance absorption at 295 keV is found to be (1∼2)x10 -28 cm 2 ·eV and is compared with that estimated from the previous experimental value for the 1277-keV level and the calculated value
International Nuclear Information System (INIS)
Mecking, B.A.
1983-11-01
The activities in the field of photonuclear physics at the Bonn 500 MeV and 2.5 GeV synchrotrons are reviewed. The experiments concentrate on photodisintegration and pion-photoproduction reactions on light nuclei. (orig.)
Photonuclear-based Detection of Nuclear Smuggling in Cargo Containers
Jones, J. L.; Haskell, K. J.; Hoggan, J. M.; Norman, D. R.; Yoon, W. Y.
2003-08-01
The Idaho National Engineering and Environmental Laboratory (INEEL) and the Los Alamos National Laboratory (LANL) have performed experiments in La Honda, California and at the Idaho Accelerator Center in Pocatello, Idaho to assess and develop a photonuclear-based detection system for shielded nuclear materials in cargo containers. The detection system, measuring photonuclear-related neutron emissions, is planned for integration with the ARACOR Eagle Cargo Container Inspection System (Sunnyvale, CA). The Eagle Inspection system uses a nominal 6-MeV electron accelerator and operates with safe radiation exposure limits to both container stowaways and to its operators. The INEEL has fabricated custom-built, helium-3-based, neutron detectors for this inspection application and is performing an experimental application assessment. Because the Eagle Inspection system could not be moved to LANL where special nuclear material was available, the response of the Eagle had to be determined indirectly so as to support the development and testing of the detection system. Experiments in California have successfully matched the delayed neutron emission performance of the ARACOR Eagle with that of the transportable INEEL electron accelerator (i.e., the Varitron) and are reported here. A demonstration test is planned at LANL using the Varitron and shielded special nuclear materials within a cargo container. Detector results are providing very useful information regarding the challenges of delayed neutron counting near the photofission threshold energy of 5.5 - 6.0 MeV, are identifying the possible utilization of prompt neutron emissions to allow enhanced signal-to-noise measurements, and are showing the overall benefits of using higher electron beam energies.
International Nuclear Information System (INIS)
Blackston, M. A.; Ahmed, M. A.; Perdue, B. A.; Weller, H. R.; Bewer, B.; Pywell, R. E.; Wurtz, W. A.; Igarashi, R.; Kucuker, S.; Norum, B.; Wang, K.; Li, J.; Mikhailov, S. F.; Popov, V. G.; Wu, Y. K.; Sawatzky, B. D.
2008-01-01
Angular distributions of the cross section and linear analyzing powers have been measured for the d(γ-vector,n)p reaction at the High Intensity γ-ray Source with linearly polarized beams of 14 and 16 MeV. The outgoing neutrons were detected using the Blowfish detector array, consisting of 88 liquid scintillator detectors with large solid angle coverage. The amplitudes of the reduced transition matrix elements were extracted by means of fits to the data and good agreement was found with a recent potential model calculation of the splittings of the triplet p-wave amplitudes. The extracted amplitudes are used to reconstruct the Gerasimov-Drell-Hearn sum rule integrand for the deuteron and are compared to theory
Energy Technology Data Exchange (ETDEWEB)
Djawotho, Pibero [College of William and Mary, Williamsburg, VA (United States)
2002-12-01
This dissertation presents results of experiment E94-010 performed at Jefferson Laboratory (simply known as JLab) in Hall A. The experiment aimed to measure the low Q^{2} evolution of the Gerasimov-Drell-Hearn (GDH) integral from Q^{2} = 0.1 to 0.9 GeV^{2}. The GDH sum rule at the real photon point provides an important test of Quantum Chromodynamics (QCD). The low Q^{2} evolution of the GDH integral contests various resonance models, Chiral Perturbation Theory ({chi} PT) and lattice QCD calculations, but more importantly, it helps us understand the transition between partonic and hadronic degrees of freedom. At high Q^{2}, beyond 1 GeV^{2}, the difference of the GDH integrals for the proton and the neutron is related to the Bjorken sum rule, another fundamental test of QCD. In addition, results of the measurements for the spin structure functions g_{1} and g_{2}, cross sections, and asymmetries are presented. E94-010 was the first experiment of its kind at JLab. It used a high-pressure, polarized ^{3}He target with a gas pressure of 10 atm and average target polarization of 35%. For the first time, the polarized electron source delivered an average beam polarization of 70% with a beam current of 15 micro A. The limit on the beam current was only imposed by the target. The experiment required six different beam energies from 0.86 to 5.1 GeV. This was the first time the accelerator ever reached 5.1 GeV. Both High-Resolution Spectrometers of Hall A, used in singles mode, were positioned at 15.5 ° each.
Pre-equilibrium particle decay in the photonuclear reactions
International Nuclear Information System (INIS)
Wu, J.R.; Chang, C.C.
1976-11-01
Calculations of particle energy spectra resulting from the photonuclear reactions at energies below the meson production threshold have been carried out in the framework of combining the pre-equilibrium exiton model and the quasi-deuteron model. A 2p-2h initial state in the exciton model is assumed because in the energy region above giant resonance the quasi-deuteron absorption is the dominant process. With these combined models, the subsequent secondary interactions of the emerging particle with the rest of the nucleus following the initial photon-nucleus interaction are appropriately taken into account. The experimental difference energy spectra of fast photoneutrons from several elements (Al, Cu, In, Sn, Ta, Pb, Bi and U) at bremsstrahlung energies of 55 and 85 MeV and the photoproton energy spectra from 12 C at bremsstrahlung energy 110 MeV were compared with the theoretical predictions. General agreements in both spectral shapes and cross sections are obtained. The relative yields of the reactions (γ, xn) resulting from monoenergetic photons on 127 I at 50, 100 and 150 MeV are also predicted reasonably well by the combined models together with the conventional evaporation theory
Atlas of giant dipole resonances. Parameters and graphs of photonuclear reaction cross sections
International Nuclear Information System (INIS)
Varlamov, A.V.; Varlamov, V.V.; Rudenko, D.S.; Stepanov, M.E.
1999-01-01
Parameters of giant dipole resonances (GDR) observed in photonuclear reaction cross sections using various beams of incident photons are presented. Data, given for 200 stable isotopes from 2 H to 243 Am including their natural compositions, were collected from papers published over the years 1951-1996. GDR parameters, such as energy positions, amplitudes and widths, are included into the table and organized by element, isotope and reaction. Graphs of the majority of the photonuclear reaction cross sections, included in the international nuclear data library EXFOR by the end of 1998, are presented. The graphs are provided for 182 stable isotopes and natural compositions. (author)
Energy Technology Data Exchange (ETDEWEB)
Filipescu, D.; Balabanski, D.L.; Constantin, P.; Gales, S.; Tesileanu, O.; Ur, C.A.; Ursu, I.; Zamfir, N.V. [Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering (IFIN-HH), Extreme Light Infrastructure - Nuclear Physics (ELI-NP), Bucharest-Magurele (Romania); Anzalone, A.; La Cognata, M.; Spitaleri, C. [INFN-LNS, Catania (Italy); Belyshev, S.S. [Lomonosov Moscow State University, Physics Faculty, Moscow (Russian Federation); Camera, F. [Departement of Physics, University of Milano, Milano (Italy); INFN section of Milano, Milano (Italy); Csige, L.; Krasznahorkay, A. [Hungarian Academy of Sciences (MTA Atomki), Institute of Nuclear Research, Post Office Box 51, Debrecen (Hungary); Cuong, P.V. [Vietnam Academy of Science and Technology, Centre of Nuclear Physics, Institute of Physics, Hanoi (Viet Nam); Cwiok, M.; Dominik, W.; Mazzocchi, C. [University of Warsaw, Warszawa (Poland); Derya, V.; Zilges, A. [University of Cologne, Institute for Nuclear Physics, Cologne (Germany); Gai, M. [University of Connecticut, LNS at Avery Point, Connecticut, Groton (United States); Gheorghe, I. [Horia Hulubei National Institute for R and D in Physics and Nuclear Engineering (IFIN-HH), Extreme Light Infrastructure - Nuclear Physics (ELI-NP), Bucharest-Magurele (Romania); University of Bucharest, Nuclear Physics Department, Post Office Box MG-11, Bucharest-Magurele (Romania); Ishkhanov, B.S. [Lomonosov Moscow State University, Physics Faculty, Moscow (Russian Federation); Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Kuznetsov, A.A.; Orlin, V.N.; Stopani, K.A.; Varlamov, V.V. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Pietralla, N. [Technische Universitat Darmstadt, Institut fur Kernphysik, Darmstadt (Germany); Sin, M. [University of Bucharest, Nuclear Physics Department, Post Office Box MG-11, Bucharest-Magurele (Romania); Utsunomiya, H. [Konan University, Department of Physics, Kobe (Japan); University of Tokyo, Center for Nuclear Study, Saitama (Japan); Weller, H.R. [Triangle Universities Nuclear Laboratory, North Carolina, Durham (United States); Duke University, Department of Physics, North Carolina, Durham (United States)
2015-12-15
The perspectives for photonuclear experiments at the new Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility are discussed in view of the need to accumulate novel and more precise nuclear data. The parameters of the ELI-NP gamma beam system are presented. The emerging experimental program, which will be realized at ELI-NP, is presented. Examples of day-one experiments with the nuclear resonance fluorescence technique, photonuclear reaction measurements, photofission experiments and studies of nuclear collective excitation modes and competition between various decay channels are discussed. The advantages which ELI-NP provides for all these experiments compared to the existing facilities are discussed. (orig.)
Experimental study of isovector spin sum rules
International Nuclear Information System (INIS)
Alexandre Deur; Peter Bosted; Volker Burkert; Donald Crabb; Kahanawita Dharmawardane; Gail Dodge; Tony Forest; Keith Griffioen; Sebastian Kuhn; Ralph Minehart; Yelena Prok
2008-01-01
We present the Bjorken integral extracted from Jefferson Lab experiment EG1b for 0.05 2 . The integral is fit to extract the twist-4 element f 2 p-n which is large and negative. Systematic studies of this higher twist analysis establish its legitimacy at Q 2 around 1 GeV 2 . We also extracted the isovector part of the generalized forward spin polarizability γ 0 . Although this quantity provides a robust test of Chiral Perturbation Theory, our data disagree with the calculations
Finite energy sum rules in potential scattering
International Nuclear Information System (INIS)
Graham, N.; Jaffe, R.L.; Quandt, M.; Weige, H.
2001-01-01
We study scattering theory identities previously obtained as consistency conditions in the context of one-loop quantum field theory calculations. We prove the identities using Jost function techniques and study applications
Experimental study of isovector spin sum rules
International Nuclear Information System (INIS)
Deur, A.; Bosted, P.; Burkert, V.; Crabb, D.; Minehart, R.; Prok, Y.; Dharmawardane, V.; Dodge, G. E.; Kuhn, S. E.; Forest, T. A.; Griffioen, K. A.
2008-01-01
We present the Bjorken integral extracted from Jefferson Lab experiment EG1b for 0.05 2 2 . The integral is fit to extract the twist-4 element f 2 p-n which appears to be relatively large and negative. Systematic studies of this higher twist analysis establish its legitimacy at Q 2 around 1 GeV 2 . We also performed an isospin decomposition of the generalized forward spin polarizability γ 0 . Although its isovector part provides a reliable test of the calculation techniques of chiral perturbation theory, our data disagree with the calculations.
International Nuclear Information System (INIS)
Adamczyk, Anne M.; Norbury, John W.; Townsend, Lawrence W.
2013-01-01
The Weisskopf–Ewing (WE) and Hauser–Feshbach (HF) theory are statistical methods, which are often used to calculate photonuclear cross sections for compound nucleus reactions. In our past work, WE methodology was presented and photonuclear reaction cross sections for nucleon emission were calculated using WE theory. Here, our previous results, which neglect pre-equilibrium emissions and do not include multiple particle emission, are compared to those calculated with HF theory and experimental data. For the reactions considered herein, it is found that the WE theory and HF method are in reasonable agreement below the two neutron separation energy assuming an energy dependent branching ratio for intermediate and heavy nuclei. In addition, qualitative confidence of WE theory for electromagnetic dissociation (EMD) cross section calculations was found. - Author-Highlights: • The Weisskopf–Ewing (WE) theory is reviewed. • Photonuclear cross sections calculated with WE theory are compared to HF predictions. • The WE theory and the HF method give similar photonuclear cross sections. • Qualitative confidence of WE theory for EMD cross section calculations is found
A measurement of the photonuclear interactions of 180 GeV muons in iron
Czech Academy of Sciences Publication Activity Database
Alexa, C.; Anderson, K.; Antonaki, A.; Lokajíček, Miloš; Němeček, Stanislav; Nessi, M.; Sýkora, I.; Vartapetian, A.; Vinogradov, V.; Zaitsov, A.
2003-01-01
Roč. 28, - (2003), s. 297-304 ISSN 1434-6044 R&D Projects: GA MPO RP-4210/69 Institutional research plan: CEZ:AV0Z1010920 Keywords : hadronic calorimeter * cross section * photonuclear ineractions * tile calorimeter Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 3.580, year: 2003
Hyperon production in photonuclear reactions on protons and deuterons : The Kappa(0)Sigma(+) channel
Lohner, H; Bacelar, J; Castelijns, R; Messchendorp, J; Shende, S; Maeda, K; Tamura, H; Nakamura, SN; Hashimoto, O
2004-01-01
With the combined setup of the Crystal Barrel and TAPS photonspectrometers at ELSA in Bonn we have studied photonuclear reactions on protons and deuterons. From the series of experiments on single and multiple neutral meson emission we concentrate here on the hyperon production off protons and
Code and data benchmarking with the new IAEA photonuclear data library
International Nuclear Information System (INIS)
Ridikas, D.; Vertes, P.
2004-01-01
As a result of an international co-operative activity, a recommended file of photonuclear reactions of 164 isotopes became available. The format and practical quality of these data are examined by using them for the calculation of photoneutron production in thick targets bombarded by photons and electrons. The Monte Carlo calculations are accomplished with a recent version of the MCNP code enhanced with a photonuclear capability. The energy range of our investigations is from the photonuclear threshold up to 150 MeV. In some cases, a comparison between our calculations and a new version of the MCNPX code, recently updated with the LANL photonuclear data files (12 isotopes) is established. Our results are also compared with the experimental data when available. These data include early measurements of the total neutron yields from thick targets bombarded by electrons as a function of energy, target thickness and atomic number, as well as recent measurements of 238 U photofission yields. We show that in general the agreement between the experimental and calculated results is satisfactory. However, a number of particular examples where this is not the case seem to exist. Most of these cases are identified. (author)
International Nuclear Information System (INIS)
Boboshin, I.N.; Varlamov, V.V.
1989-04-01
In order to provide the necessary nuclear physics data from the ENSDF file to those carrying out fundamental or applied photonuclear research a specialized software system was set up on an ES computer. A brief description of the block diagram of this software package and of one of the programs in this package (SUPER) is given. 4 refs, 6 figs
International Nuclear Information System (INIS)
1997-04-01
The present report contains the summary of the first Research Co-ordination Meeting on ''Compilation and Evaluation of Photonuclear Data for Applications'', held in Obninsk, Russia, from 3 to 6 December 1996. The project aims to produce a Technical Document on Photonuclear Data Library for Applications and to develop an IAEA Photonuclear Data Library. Summarized are the conclusions and recommendations of the meeting together with a detailed list of actions. Attached is the information sheet on the project, the agenda of the meeting and the list of participants along with extended abstracts of their presentations. Refs, figs, tabs
Alabdulmohsin, Ibrahim M.
2018-03-07
We will begin our treatment of summability calculus by analyzing what will be referred to, throughout this book, as simple finite sums. Even though the results of this chapter are particular cases of the more general results presented in later chapters, they are important to start with for a few reasons. First, this chapter serves as an excellent introduction to what summability calculus can markedly accomplish. Second, simple finite sums are encountered more often and, hence, they deserve special treatment. Third, the results presented in this chapter for simple finite sums will, themselves, be used as building blocks for deriving the most general results in subsequent chapters. Among others, we establish that fractional finite sums are well-defined mathematical objects and show how various identities related to the Euler constant as well as the Riemann zeta function can actually be derived in an elementary manner using fractional finite sums.
Alabdulmohsin, Ibrahim M.
2018-01-01
We will begin our treatment of summability calculus by analyzing what will be referred to, throughout this book, as simple finite sums. Even though the results of this chapter are particular cases of the more general results presented in later chapters, they are important to start with for a few reasons. First, this chapter serves as an excellent introduction to what summability calculus can markedly accomplish. Second, simple finite sums are encountered more often and, hence, they deserve special treatment. Third, the results presented in this chapter for simple finite sums will, themselves, be used as building blocks for deriving the most general results in subsequent chapters. Among others, we establish that fractional finite sums are well-defined mathematical objects and show how various identities related to the Euler constant as well as the Riemann zeta function can actually be derived in an elementary manner using fractional finite sums.
Yurinsky, Vadim Vladimirovich
1995-01-01
Surveys the methods currently applied to study sums of infinite-dimensional independent random vectors in situations where their distributions resemble Gaussian laws. Covers probabilities of large deviations, Chebyshev-type inequalities for seminorms of sums, a method of constructing Edgeworth-type expansions, estimates of characteristic functions for random vectors obtained by smooth mappings of infinite-dimensional sums to Euclidean spaces. A self-contained exposition of the modern research apparatus around CLT, the book is accessible to new graduate students, and can be a useful reference for researchers and teachers of the subject.
International Nuclear Information System (INIS)
2000-10-01
This document provides users of photonuclear data with an up-to-date overview of photonuclear reaction data. In addition to production cross sections, energy and angular distributions of the emitted particles are provided. The material is presented in a systematic way, covering experimental data and their compilation, an introduction to relevant parts of nuclear reaction theory, an exposition of evaluation methodology used to generate evaluations, an intercomparison of different evaluations, and a description of the IAEA Photonuclear Data Library
Photonuclear reaction as a probe for α -clustering nuclei in the quasi-deuteron region
Huang, B. S.; Ma, Y. G.; He, W. B.
2017-03-01
Photon-nuclear reaction in a transport model frame, namely an extended quantum molecular dynamics model, has been realized at the photon energy of 70-140 MeV in the quasi-deuteron regime. For an important application, we pay a special focus on photonuclear reactions of 12C(γ ,n p )10B where 12C is considered as different configurations including α clustering. Obvious differences for some observables have been observed among different configurations, which can be attributed to spatial-momentum correlation of a neutron-proton pair inside nucleus, and therefore it gives us a sensitive probe to distinguish the different configurations including α clustering with the help of the photonuclear reaction mechanism.
Photonuclear and Radiation Effects Testing with a Refurbished 20 MeV Medical Electron Linac
Webb, Timothy; Beezhold, Wendland; De Veaux, Linda C; Harmon, Frank; Petrisko, Jill E; Spaulding, Randy
2005-01-01
An S-band 20 MeV electron linear accelerator formerly used for medical applications has been recommissioned to provide a wide range of photonuclear activation studies as well as various radiation effects on biological and microelectronic systems. Four radiation effect applications involving the electron/photon beams are described. Photonuclear activation of a stable isotope of oxygen provides an active means of characterizing polymer degradation. Biological irradiations of microorganisms including bacteria were used to study total dose and dose rate effects on survivability and the adaptation of these organisms to repeated exposures. Microelectronic devices including bipolar junction transistors (BJTs) and diodes were irradiated to study photocurrent from these devices as a function of peak dose rate with comparisons to computer modeling results. In addition, the 20 MeV linac may easily be converted to a medium energy neutron source which has been used to study neutron damage effects on transistors.
Application of photonuclear methods of analysis in biology, medicine, ecological studies
International Nuclear Information System (INIS)
Burmistenko, Yu.N.
1986-01-01
Examples of application of photonuclear methods of analysis (PhMA) of the substance composition in biology, medicine, ecology are considered. The methods for determining the element composition of soft and bone tissues, blood, urine are developed. The results of studying the limits of determination of different elements are presented. In ecological investigations PhMA is applied for studying the composition of atmospheric aerosols, industrial sewage, canalization wastes, pollution of soil, plants, animals with toxic elements
On the usage of electron beam as a tool to produce radioactive isotopes in photonuclear reactions
International Nuclear Information System (INIS)
Bunatyan, G.G.; Nikolenko, V.G.; Popov, A.B.
2009-01-01
We treat the Bremsstrahlung, induced by initial electron beam in converter, and the production of a desirable radioisotope due to the photonuclear reaction caused by this Bremsstrahlung. By way of illustration, the yield of a number of some, the most applicable in practice, radioisotopes is evaluated. The acquired findings persuade us that usage of modern electron accelerators offers a practicable way to produce the radioisotopes needful nowadays for various valuable applications in the nuclear medicine
DEFF Research Database (Denmark)
Brodal, Gerth Stølting; Jørgensen, Allan Grønlund
2008-01-01
In an array of n numbers each of the \\binomn2+nUnknown control sequence '\\binom' contiguous subarrays define a sum. In this paper we focus on algorithms for selecting and reporting maximal sums from an array of numbers. First, we consider the problem of reporting k subarrays inducing the k largest...... sums among all subarrays of length at least l and at most u. For this problem we design an optimal O(n + k) time algorithm. Secondly, we consider the problem of selecting a subarray storing the k’th largest sum. For this problem we prove a time bound of Θ(n · max {1,log(k/n)}) by describing...... an algorithm with this running time and by proving a matching lower bound. Finally, we combine the ideas and obtain an O(n· max {1,log(k/n)}) time algorithm that selects a subarray storing the k’th largest sum among all subarrays of length at least l and at most u....
Multiparty symmetric sum types
DEFF Research Database (Denmark)
Nielsen, Lasse; Yoshida, Nobuko; Honda, Kohei
2010-01-01
This paper introduces a new theory of multiparty session types based on symmetric sum types, by which we can type non-deterministic orchestration choice behaviours. While the original branching type in session types can represent a choice made by a single participant and accepted by others...... determining how the session proceeds, the symmetric sum type represents a choice made by agreement among all the participants of a session. Such behaviour can be found in many practical systems, including collaborative workflow in healthcare systems for clinical practice guidelines (CPGs). Processes...... with the symmetric sums can be embedded into the original branching types using conductor processes. We show that this type-driven embedding preserves typability, satisfies semantic soundness and completeness, and meets the encodability criteria adapted to the typed setting. The theory leads to an efficient...
Xu, Yi; Luo, Wen; Balabanski, Dimiter; Goriely, Stephane; Matei, Catalin; Tesileanu, Ovidiu
2017-09-01
The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the astrophysical reaction rates of (γ,n), (γ,p), and (γ,α) reactions are computed within the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12 Infrastructure-Nuclear Physics (ELI-NP) facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p) and 96Ru(γ,α) are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.
African Journals Online (AJOL)
Tracie1
Résumé. L'activité traduisant est un processus très compliqué qui exige la connaissance extralinguistique chez le traducteur. Ce travail est basé sur la traduction littéraire. La traduction littéraire consistedes textes littéraires que comprennent la poésie, le théâtre, et la prose. La traduction littéraire a quelques problèmes ...
International Nuclear Information System (INIS)
Tran Duc Thiep; Nguyen Van Do; Nguyen Khac Thi; Truong Thi An; Nguyen Ngoc Son
2004-01-01
Microtrons are accelerators of electrons and are simultaneous source of Bremsstrahlung photon flux and fission neutrons. In 1982, a microtron of seventeen trajectories Microtron MT - 17 was put into operation at the National Institute of Physics of Vietnam. Though very modest, microtrons are very useful for developing countries such as Vietnam in both fundamental and applied physics research. During the recent years by using the above mentioned MT - 17 and microtrons from other institutes we have carried out different investigation. In this report we present some results obtained in the studies of photonuclear reactions and photon activation analysis in the giant dipole resonance region. (author)
Measurement of neutron spectra for photonuclear reaction with linearly polarized photons
Directory of Open Access Journals (Sweden)
Kirihara Yoichi
2017-01-01
Full Text Available Spectra of neutrons produced by a photonuclear reaction from a 197Au target were measured using 16.95 MeV linearly and circularly polarized photon beams at NewSUBARU-BL01 using a time-of-flight method. The difference in the neutron spectra between the cases of a linearly and circularly polarized photon was measured. The difference in the neutron yield increased with the neutron energy and was approximately threefold at the maximum neutron energy. In a direction perpendicular to that of the linear polarization, the neutron yields decreased as the neutron energy increased.
Coherent and incoherent J /ψ photonuclear production in an energy-dependent hot-spot model
Cepila, J.; Contreras, J. G.; Krelina, M.
2018-02-01
In a previous publication, we have presented a model for the photoproduction of J /ψ vector mesons off protons, where the proton structure in the impact-parameter plane is described by an energy-dependent hot-spot profile. Here we extend this model to study the photonuclear production of J /ψ vector mesons in coherent and incoherent interactions of heavy nuclei. We study two methods to extend the model to the nuclear case: using the standard Glauber-Gribov formalism and using geometric scaling to obtain the nuclear saturation scale. We find that the incoherent cross section changes sizably with the inclusion of subnucleonic hot spots and that this change is energy dependent. We propose to search for this behavior by measuring the ratio of the incoherent to coherent cross sections at different energies. We compare the results of our model to results from the Relativistic Heavy-Ion Collider (RHIC) and from run 1 at the Large Hadron Collider (LHC), finding satisfactory agreement. We also present predictions for the LHC at the new energies reached in run 2. The predictions include J /ψ production in ultraperipheral collisions, as well as the recently observed photonuclear production in peripheral collisions.
Darmann, Andreas; Nicosia, Gaia; Pferschy, Ulrich; Schauer, Joachim
2014-03-16
In this work we address a game theoretic variant of the Subset Sum problem, in which two decision makers (agents/players) compete for the usage of a common resource represented by a knapsack capacity. Each agent owns a set of integer weighted items and wants to maximize the total weight of its own items included in the knapsack. The solution is built as follows: Each agent, in turn, selects one of its items (not previously selected) and includes it in the knapsack if there is enough capacity. The process ends when the remaining capacity is too small for including any item left. We look at the problem from a single agent point of view and show that finding an optimal sequence of items to select is an [Formula: see text]-hard problem. Therefore we propose two natural heuristic strategies and analyze their worst-case performance when (1) the opponent is able to play optimally and (2) the opponent adopts a greedy strategy. From a centralized perspective we observe that some known results on the approximation of the classical Subset Sum can be effectively adapted to the multi-agent version of the problem.
International Nuclear Information System (INIS)
Moraes, M.A.P. de.
1990-01-01
The photonuclear cross sections of U-293 and Pu-239 have been studied by using monochromatic and discrete photons, in the energy interval from 5.49 to 9.72 MeV, produced by thermal neutron capture. The gamma fluxes incident on the samples were measured using a ( 3 x 3 )'' NaI (TI) crystal. The photofission fragments were detected in Makrofol-Kg (SSNTD). A possible structure was observed in the U-233 cross sections, near 7.23 MeV. The relative fissionability of the nuclides was determined at each excitation energy and shown to be energy independent: ( 2.12 ± 0.25) for U-233 and ( 3.32 ± 0.41 ) for Pu-239. The angular distribution of photofission fragments of Pu-239 were measured at two mean excitation energies of 5.43 and 7.35 MeV. An anisotropic distribution of ( 12.2 ± 3.6 ) % was observed at 5.43 MeV. The total neutron cross sections were measured by using a long counter detector. The photoneutron cross sections were calculated by using energy dependent neutron multiplicities values, γ(E), obtained in the literature. The competition Γn/γf was also determined at each excitation energy, and shown to be energy independent: ( 0.54 ± 0.05 ) for U-233 and ( 0.44 ± 0.05 ) for Pu-239, and were correlated to the parameters Z sup(2)/A, ( Ef'-Bn'), A. According to the FUJIMOTO-YAMAGUCHI and CONSTANT NUCLEAR TEMPERATURE models, the nuclear temperatures were calculated. The total photoabsorption cross sections were also calculated as a sum of the photofission and photoneutron cross sections at each energy excitation. From these results the competition Γf/ΓA, called fission probability Pf, were obtained: ( 0.66 ± 0.02) for U-233 and ( 0.70 ± 0.02 ) for Pu-239. (author)
Counting Triangles to Sum Squares
DeMaio, Joe
2012-01-01
Counting complete subgraphs of three vertices in complete graphs, yields combinatorial arguments for identities for sums of squares of integers, odd integers, even integers and sums of the triangular numbers.
Directory of Open Access Journals (Sweden)
Xu Y.
2018-01-01
Full Text Available The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the impact of nuclear ingredients, especially the nuclear potential, level density and strength function, to the astrophysical re-action rates of (p,γ, (α,γ, (γ,p, and (γ,α reactions are systematically studied. The calculations are performed basad on the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12≤Z≤110. In particular, both of the Wood-Saxon potential and the microscopic folding potential are taken into account. It is found that both the capture and photonuclear reaction rates are very sensitive to the nuclear potential, thus the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p and 96Ru(γ,α are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.
Xu, Y.; Goriely, S.; Balabanski, D. L.; Chesnevskaya, S.; Guardo, G. L.; La Cognata, M.; Lan, H. Y.; Lattuada, D.; Luo, W.; Matei, C.
2018-05-01
The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the impact of nuclear ingredients, especially the nuclear potential, level density and strength function, to the astrophysical re-action rates of (p,γ), (α,γ), (γ,p), and (γ,α) reactions are systematically studied. The calculations are performed basad on the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12≤Z≤110. In particular, both of the Wood-Saxon potential and the microscopic folding potential are taken into account. It is found that both the capture and photonuclear reaction rates are very sensitive to the nuclear potential, thus the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p) and 96Ru(γ,α) are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.
DeTemple, Duane
2010-01-01
Purely combinatorial proofs are given for the sum of squares formula, 1[superscript 2] + 2[superscript 2] + ... + n[superscript 2] = n(n + 1) (2n + 1) / 6, and the sum of sums of squares formula, 1[superscript 2] + (1[superscript 2] + 2[superscript 2]) + ... + (1[superscript 2] + 2[superscript 2] + ... + n[superscript 2]) = n(n + 1)[superscript 2]…
Neutron, Proton, and Photonuclear Cross Sections for Radiation Therapy and Radiation Protection
International Nuclear Information System (INIS)
Chadwick, M.B.
1998-01-01
The authors review recent work at Los Alamos to evaluate neutron, proton, and photonuclear cross section up to 150 MeV (to 250 MeV for protons), based on experimental data and nuclear model calculations. These data are represented in the ENDF format and can be used in computer codes to simulate radiation transport. They permit calculations of absorbed dose in the body from therapy beams, and through use of kerma coefficients allow absorbed dose to be estimated for a given neutron energy distribution. For radiation protection, these data can be used to determine shielding requirements in accelerator environments, and to calculate neutron, proton, gamma-ray, and radionuclide production. Illustrative comparisons of the evaluated cross section and kerma coefficient data with measurements are given
Photonuclear processes in the treatment room and patient during radiation therapy with 50 MV photons
Energy Technology Data Exchange (ETDEWEB)
Gudowska, Irena [Karolinska Inst., Stockholm (Sweden). Dept. of Radiation Physics
1997-10-01
The objectives of this project were to determine the level of photoneutron radiation around the MM50 Racetrack Microtron at Karolinska Hospital, operating in different modes and to evaluate the photonuclear absorbed dose to the treated volume during therapy with a 50 MV photon beam. The photoneutron radiation has been studied both using a {sup 235}U fission chamber and by computer simulation. The estimated neutron equivalent dose due to accelerator produced neutrons delivered to the tissues inside and outside the treatment volume do not exceed the recommended values. However, there is a potential risk that the sensitive tissues (lens of the eye and gonads), outside the treatment volume, can receive a dose of about 300-500 mSv per photon treatment course of 60 Gy with a slight increase for secondary malignancies. 47 refs, 15 figs, 6 tabs.
Photonuclear processes in the treatment room and patient during radiation therapy with 50 MV photons
International Nuclear Information System (INIS)
Gudowska, Irena
1997-01-01
The objectives of this project were to determine the level of photoneutron radiation around the MM50 Racetrack Microtron at Karolinska Hospital, operating in different modes and to evaluate the photonuclear absorbed dose to the treated volume during therapy with a 50 MV photon beam. The photoneutron radiation has been studied both using a 235 U fission chamber and by computer simulation. The estimated neutron equivalent dose due to accelerator produced neutrons delivered to the tissues inside and outside the treatment volume do not exceed the recommended values. However, there is a potential risk that the sensitive tissues (lens of the eye and gonads), outside the treatment volume, can receive a dose of about 300-500 mSv per photon treatment course of 60 Gy with a slight increase for secondary malignancies. 47 refs, 15 figs, 6 tabs
International Nuclear Information System (INIS)
Varlamov, V.V.; Efimkin, N.G.; Ishkhanov, B.S.; Sapunenko, V.V.
1994-12-01
The authors describe a method based on the reduction method for the evaluation of photonuclear reaction cross-sections obtained under conditions where there are large systematic uncertainties (different instrumental functions, calibration and normalization errors). The evaluation method involves using the actual instrumental function (photon spectrum) of each individual experiment to reduce the data to a representation generated by an instrumental function of better quality. The objective is to find the most reasonably achievable monoenergetic representation of the information on the reaction cross-section derived from the results of various experiments and to take into account the calibration and normalization errors in these experiments. The method was used to obtain the evaluated total photoneutron reaction cross-section (γ,xn) for a large number of nuclei. Data obtained for 16 O and 208 Pb are presented. (author). 36 refs, 6 figs, 4 tabs
Social Security Administration — Staging Instance for all SUMs Counts related projects including: Redeterminations/Limited Issue, Continuing Disability Resolution, CDR Performance Measures, Initial...
Maua, Denis Deratani; Cozman, Fabio Gagli; Conaty, Diarmaid; de Campos, Cassio P.
2017-01-01
Sum-product networks are a relatively new and increasingly popular class of (precise) probabilistic graphical models that allow for marginal inference with polynomial effort. As with other probabilistic models, sum-product networks are often learned from data and used to perform classification.
UPC photo-nuclear dijet production in 5.02 TeV Pb+Pb collisions
Angerami, Aaron; The ATLAS collaboration
2017-01-01
Ultra-peripheral heavy ion collisions provide a unique opportunity to study the parton distributions in the colliding nuclei via the measurement of photo-nuclear dijet production. An analysis of dijet production in ultra-peripheral $\\sqrt{s}_{\\mathrm{NN}}$=5.02 TeV Pb+Pb collisions performed using data collected in 2015 is described. The data set corresponds to a total integrated luminosity of 0.38 $\\mathrm{nb}^{−1}$. The ultra-peripheral collisions are selected using a combination of trigger, zero degree calorimeter, and gap requirements. The jets are reconstructed using the anti-$k_t$ algorithm. The results of the measurement include cross-sections for photo-nuclear dijet production as a function of different dijet kinematic variables.
International Nuclear Information System (INIS)
Chadwick, M.B.; Young, P.G.
1994-08-01
The authors have developed the GNASH code to include photonuclear reactions for incident energies up to 140 MeV. Photoabsorption is modeled through the giant resonance at the lower energies, and the quasideuteron mechanism at the higher energies, and the angular momentum coupling of the incident photon to the target is properly accounted for. After the initial interaction, primary and multiple preequilibrium emission of fast particles can occur before compound nucleus decay from the equilibrated compound nucleus. The angular distributions from compound nucleus decay are taken as isotropic, and those from preequilibrium emission (which they obtain from a phase-space model which conserves momentum) are forward-peaked. To test the new modeling they apply the code to calculate photonuclear reactions on 208 Pb for incident energies up to 140 MeV
Moreno, Carlos J
2005-01-01
Introduction Prerequisites Outline of Chapters 2 - 8 Elementary Methods Introduction Some Lemmas Two Fundamental Identities Euler's Recurrence for Sigma(n)More Identities Sums of Two Squares Sums of Four Squares Still More Identities Sums of Three Squares An Alternate Method Sums of Polygonal Numbers Exercises Bernoulli Numbers Overview Definition of the Bernoulli Numbers The Euler-MacLaurin Sum Formula The Riemann Zeta Function Signs of Bernoulli Numbers Alternate The von Staudt-Clausen Theorem Congruences of Voronoi and Kummer Irregular Primes Fractional Parts of Bernoulli Numbers Exercises Examples of Modular Forms Introduction An Example of Jacobi and Smith An Example of Ramanujan and Mordell An Example of Wilton: t (n) Modulo 23 An Example of Hamburger Exercises Hecke's Theory of Modular FormsIntroduction Modular Group ? and its Subgroup ? 0 (N) Fundamental Domains For ? and ? 0 (N) Integral Modular Forms Modular Forms of Type Mk(? 0(N);chi) and Euler-Poincare series Hecke Operators Dirichlet Series and ...
Proximinality in generalized direct sums
Directory of Open Access Journals (Sweden)
Darapaneni Narayana
2004-01-01
Full Text Available We consider proximinality and transitivity of proximinality for subspaces of finite codimension in generalized direct sums of Banach spaces. We give several examples of Banach spaces where proximinality is transitive among subspaces of finite codimension.
Studies of photonuclear neutron emission during the start-up phase of the Alcator C tokamak
International Nuclear Information System (INIS)
Pappas, D.S.; Furnstahl, R.; Kochanski, G.P.
1981-05-01
Alcator C operations commenced with discharge cleaning and tokamak operation using hydrogen filling gas. Prior to and during these experiments no deuterium gas was allowed into the device. The earliest operation resulted in dosimeter readings of a few Roentgen per shot in the vicinity of the limiter and a localized source of neutron emission of up to 10 9 neutrons/shot. A strong correlation of the neutron emissions with hard x-ray emissions from the limiter and nonthermal features on the synchrotron emissions was observed during these discharges. Gamma energy spectroscopy of the activated limiter after removal from Alcator allowed identification of 16 radioisotopes which were consistent with photonuclear processes (γ,n , γ,p , γ,α reactions) arising in the limiter. After seven months of hydrogen operation conditions were achieved that resulted in substantially less non-thermal activity. Typical neutron emission rates of equal to or less than 10 6 n/sec were observed, i.e., about four orders of magnitude less than the expected D-D thermonuclear neutron emission rates for the same type of discharge if D 2 was used as the filling gas
International Nuclear Information System (INIS)
Dikij, N.P.; Rudychev, Y.V.; Fedorchenko, D.V.; Khazhmuradov, M.A.
2014-01-01
This paper considers a method for 67 Cu isotope production using electron bremsstrahlung by the 68 Zn(gamma, p) 67 Cu reaction. The facility for 67 Cu isotope production contains an electron accelerator, electron-gamma converter and zinc target. To optimize this facility we developed three-dimensional model of the converter and the target. Using this model, we performed the mathematical modeling of zinc target irradiation and thermal-hydraulic processes inside the target for various parameters of the electron beam and converter configurations. For mathematical modeling of radiation processes we used the MCNPX software. Thermal-hydraulic simulation utilized the commercial SolidWorks software with Flow Simulation module. Mathematical modeling revealed that efficient 67 Cu isotope production needs smaller beam diameter and higher electron energy. Under these conditions target heat power also increases, thus additional cooling is necessary. If the beam diameter and the electron energy are fixed the most effective method to satisfy the operating parameters and retain an efficient isotope yield is to optimize photonuclear spectra of the target by variation of converter thickness. We developed an algorithm for multicriterion optimization and performed the optimization of the facility with account to coupled radiation and heat transfer processes.
Applications of the photo-nuclear reaction data for activation analysis
International Nuclear Information System (INIS)
Odsuren, M.; Khuukhenkhuu, G.; Turbold, A.; Davaa, S.; Baatarkhuu, D.
2015-01-01
In the relative method of activation analysis by continuum wide spectrum gamma-rays the same isotope is usually used for standard reference element and sample material in connection with different dependence of the reaction cross sections on the irradiation beam energy. But, in practice suitable isotopes for reference element are not always available. So, in this paper, we suggest a new method for photo-activation analysis in which is used the correction factor. This factor takes into account the difference in the photo-nuclear reaction cross section dependence on the gamma-ray energy for standard reference isotope and sample elements. The correction factor is determined by three methods of experimental, theoretical and TALYS evaluation. Pure metal foils of Au, Cu and Mo were irradiated by bremsstrahlung gamma-rays on the electron cyclic accelerator Microtron MT-22 at the Nuclear Research Center, National University of Mongolia. Gamma spectra of the activated metal foils were measured by HP-Ge detector to obtain element contents in the samples. It was shown that experimental results with correction factors are satisfactorily in agreement with real values of the element contents in the samples
Giant dipole resonance by many levels theory
International Nuclear Information System (INIS)
Mondaini, R.P.
1977-01-01
The many levels theory is applied to photonuclear effect, in particular, in giant dipole resonance. A review about photonuclear dipole absorption, comparing with atomic case is done. The derivation of sum rules; their modifications by introduction of the concepts of effective charges and mass and the Siegert theorem. The experimental distributions are compared with results obtained by curve adjustment. (M.C.K.) [pt
Small sum privacy and large sum utility in data publishing.
Fu, Ada Wai-Chee; Wang, Ke; Wong, Raymond Chi-Wing; Wang, Jia; Jiang, Minhao
2014-08-01
While the study of privacy preserving data publishing has drawn a lot of interest, some recent work has shown that existing mechanisms do not limit all inferences about individuals. This paper is a positive note in response to this finding. We point out that not all inference attacks should be countered, in contrast to all existing works known to us, and based on this we propose a model called SPLU. This model protects sensitive information, by which we refer to answers for aggregate queries with small sums, while queries with large sums are answered with higher accuracy. Using SPLU, we introduce a sanitization algorithm to protect data while maintaining high data utility for queries with large sums. Empirical results show that our method behaves as desired. Copyright © 2014 Elsevier Inc. All rights reserved.
Measurement sum theory and application - Application to low level measurements
International Nuclear Information System (INIS)
Puydarrieux, S.; Bruel, V.; Rivier, C.; Crozet, M.; Vivier, A.; Manificat, G.; Thaurel, B.; Mokili, M.; Philippot, B.; Bohaud, E.
2015-09-01
In laboratories, most of the Total Sum methods implemented today use substitution or censure methods for nonsignificant or negative values, and thus create biases which can sometimes be quite large. They are usually positive, and generate, for example, becquerel (Bq) counting or 'administrative' quantities of materials (= 'virtual'), thus artificially falsifying the records kept by the laboratories under regulatory requirements (environment release records, waste records, etc.). This document suggests a methodology which will enable the user to avoid such biases. It is based on the following two fundamental rules: - The Total Sum of measurement values must be established based on all the individual measurement values, even those considered non-significant including the negative values. Any modification of these values, under the pretext that they are not significant, will inevitably lead to biases in the accumulated result and falsify the evaluation of its uncertainty. - In Total Sum operations, the decision thresholds are arrived at in a similar way to the approach used for uncertainties. The document deals with four essential aspects of the notion of 'measurement Total Sums': - The expression of results and associated uncertainties close to Decision Thresholds, and Detection or Quantification Limits, - The Total Sum of these measurements: sum or mean, - The calculation of the uncertainties associated with the Total Sums, - Result presentation (particularly when preparing balance sheets or reports, etc.) Several case studies arising from different situations are used to illustrate the methodology: environmental monitoring reports, release reports, and chemical impurity Total Sums for the qualification of a finished product. The special case of material balances, in which the measurements are usually all significant and correlated (the covariance term cannot then be ignored) will be the subject of a future second document. This
A Friedel sum rule for the dyon charge
International Nuclear Information System (INIS)
Grossman, B.
1984-01-01
This chapter considers the magnetic monopole as an impurity in the Dirac sea in order to gain an understanding of the ground state of the magnetic monopole. In a CP violating theory, the magnetic monopole acquires a non-zero electric charge that does not violate any quantization condition. The discussion is restricted to a point abelian magnetic monopole. The Atiyah-Singer index the orem is used by dimensional reduction from four-dimensions
The Thomas-Kuhn sum rule and superfluidity, 2
International Nuclear Information System (INIS)
Izuyama, Takeo
1977-01-01
Since the ODLRO by itself cannot always lead to dynamical superfluidity, we must seek for a supplementary condition for the persistent flow. The condition found here is that, even when weak impurities exist, the Josephson-Baym phase fluctuation spectrum remains to be valid for long wave-length components of the fluctuation including the extreme cases k=(2π/L), (4π/L),.... (auth.)
Many body effects in nuclear matter QCD sum rules
Drukarev, E. G.; Ryskin, M. G.; Sadovnikova, V. A.
2017-12-01
We calculate the single-particle nucleon characteristics in symmetric nuclear matter with inclusion of the 3N and 4N interactions. We calculated the contribution of the 3N interactions earlier, now we add that of the 4N ones. The contribution of the 4N forces to nucleon self energies is expressed in terms of the nonlocal scalar condensate (d = 3) and of the configurations of the vector-scalar and the scalar-scalar quark condensates (d = 6) in which two diquark operators act on two different nucleons of the matter.These four-quark condensates are obtained in the model-independent way. The density dependence of the nucleon effective mass, of the vector self energy and of the single-particle potential energy are obtained. We traced the dependence of the nucleon characteristics on the actual value of the pion-nucleon sigma term. We obtained also the nucleon characteristics in terms of the quasifree nucleons, with the noninteracting nucleons surrounded by their pion clouds as the starting point. This approach leads to strict hierarchy of the many body forces.
Chromium and titanium isotopes produced in photonuclear reactions of vanadium, revisited
Sakamoto, K.; Yoshida, M.; Kubota, Y.; Fukasawa, T.; Kunugise, A.; Hamajima, Y.; Shibata, S.; Fujiwara, I.
1989-10-01
Photonuclear production yields of 51Ti und 51,49,48Cr from 51V were redetermined for bremsstrahlung end-point energies ( E0) of 30 to 1000 or 1050 MeV with the aid of radiochemical separation of Cr. The yield curves for 51Ti, 51Cr, 49Cr and 48Cr show a clear evidence for two components in the production process; one tor secondary-proton reactions at E0 Q, Qπ being Q-values for (γ, π +) and ( γ, π+xn) reactions. The contributions of the secondary reactions for production of the Ti and Cr isotopes at E0 > Qπ were then estimated by fitting calculated secondary yields to the observed ones at E0 code and the reported photoneutron and photoproton spectra from 12C and some other complex nuclei. The present results for 49Cr are close to the reported ones, while the present 48Cr yields differ by a factor of about 50. For the 51Ti and 51Cr yields, there are some discrepancies between the present and reported ones. The yield corrected for the secondaries, in units of μb/equivalent quantum, were unfolded into cross sections per photon, in units of μb, as a function ol monochromatic photon energy with the LOUHI-82 code. The results for the 51Ti and 49Cr are in disagreement in both the magnitude and shape with the theoretical predictions based on DWIA and PWIA. A Monte Carlo calculation based on the PICA code by Gabriel and Alsmiller does reproduce the gross feature of the present results.
International Nuclear Information System (INIS)
Aniel, Thierry.
1982-06-01
The performance of photon beams obtained by two different tagging processes (tagging of ''hard'' annihilation photons with ''soft'' associated photons, tagging of bremstrahlung photons with associated electrons) on the same facility was studied. The two processes are described and experimental results on the characteristics of the resulting beams given. The respective advantages of both methods are compared with one another and with those of a quasi-monochromatic beam obtained by the in-flight annihilation of a positron beam. A development based on the second process is then studied together with its applications to photonuclear physics [fr
International Nuclear Information System (INIS)
Goriely, S.; Dimitriou, P.
2016-07-01
A summary is given of the 1 st Research Coordination Meeting of the new IAEA Co-ordinated Research Project (CRP) on Updating the Photonuclear Data Library and Generating a Reference Database for Photon Strength Functions. Participants presented their work, reviewed the current status of the field with regards to measurements, theoretical models and evaluations, discussed the scope of the work to be undertaken and agreed on a list of priorities and task assignments necessary to achieve the goals of the CRP. A summary of the presentations and discussions is presented in this report. (author)
Sums of Generalized Harmonic Series
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 20; Issue 9. Sums of Generalized Harmonic Series: For Kids from Five to Fifteen. Zurab Silagadze. General Article Volume 20 Issue 9 September 2015 pp 822-843. Fulltext. Click here to view fulltext PDF. Permanent link:
Energy Technology Data Exchange (ETDEWEB)
Luo, Wen, E-mail: wenluo-ok@163.com [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China); Lan, Hao-yang [School of Nuclear Science and Technology, University of South China, Hengyang 421001 (China); Xu, Yi; Balabanski, Dimiter L. [Extreme Light Infrastructure-Nuclear Physics, “Horia Hulubei” National Institute for Physics and Nuclear Engineering (IFIN-HH), 30 Reactorului, 077125 Bucharest-Magurele (Romania)
2017-03-21
A data-based Monte Carlo simulation algorithm, Geant4-GENBOD, was developed by coupling the n-body Monte-Carlo event generator to the Geant4 toolkit, aiming at accurate simulations of specific photonuclear reactions for diverse photonuclear physics studies. Good comparisons of Geant4-GENBOD calculations with reported measurements of photo-neutron production cross-sections and yields, and with reported energy spectra of the {sup 6}Li(n,α)t reaction were performed. Good agreements between the calculations and experimental data were found and the validation of the developed program was verified consequently. Furthermore, simulations for the {sup 92}Mo(γ,p) reaction of astrophysics relevance and photo-neutron production of {sup 99}Mo/{sup 99m}Tc and {sup 225}Ra/{sup 225}Ac radioisotopes were investigated, which demonstrate the applicability of this program. We conclude that the Geant4-GENBOD is a reliable tool for study of the emerging experiment programs at high-intensity γ-beam laboratories, such as the Extreme Light Infrastructure – Nuclear Physics facility and the High Intensity Gamma-Ray Source at Duke University.
International Nuclear Information System (INIS)
Tran Duc Thiep; Truong Thi An; Phan Viet Cuong; Nguyen The Vinh; Bui Minh Hue; Belov, A.G.; Maslov, O.D.; Mishinsky, G.V.; Zhemenik, V.I.
2017-01-01
We have determined the isomeric ratios of isomeric pairs "9"7"m","gNb, "9"5"m","gNb and "9"1"m","gMo produced in "9"8Mo(γ, p)"9"7"m","gNb, "9"6Mo(γ, p)"9"5"m","gNb and "9"2Mo(γ, n)"9"1"m","gMo photonuclear reactions in the giant dipole resonance (GDR) region by the activation method. The results were analyzed, discussed and compared with the similar data from literature to examine the role of excitation energy, neutron configuration, channel effect, and direct and pre-equilibrium processes in (γ, p) photonuclear reactions. In this work the isomeric ratios for "9"7"m","gNb from 14 to 19 MeV, for "1"9"5"m","gNb from 14 to 24 MeV except 20 and 23.5 MeV and for "9"1"m","gMo at 14 and 15 MeV were first measured.
African Journals Online (AJOL)
ISONIC
Résumé. Cardisoma armatum, est une espèce de crabe de terre rencontrée en Afrique de l'ouest en particulier en ... optique suite au traitement histologique ont permis la mise en évidence de quelques critères d'identification de l'espèce et ...... En Côte d'Ivoire il n'est pas rare de voir durant les saisons propices. Cardisoma ...
International Nuclear Information System (INIS)
Janek, S; Svensson, R; Jonsson, C; Brahme, A
2006-01-01
A method for dose delivery monitoring after high energy photon therapy has been investigated based on positron emission tomography (PET). The technique is based on the activation of body tissues by high energy bremsstrahlung beams, preferably with energies well above 20 MeV, resulting primarily in 11 C and 15 O but also 13 N, all positron-emitting radionuclides produced by photoneutron reactions in the nuclei of 12 C, 16 O and 14 N. A PMMA phantom and animal tissue, a frozen hind leg of a pig, were irradiated to 10 Gy and the induced positron activity distributions were measured off-line in a PET camera a couple of minutes after irradiation. The accelerator used was a Racetrack Microtron at the Karolinska University Hospital using 50 MV scanned photon beams. From photonuclear cross-section data integrated over the 50 MV photon fluence spectrum the predicted PET signal was calculated and compared with experimental measurements. Since measured PET images change with time post irradiation, as a result of the different decay times of the radionuclides, the signals from activated 12 C, 16 O and 14 N within the irradiated volume could be separated from each other. Most information is obtained from the carbon and oxygen radionuclides which are the most abundant elements in soft tissue. The predicted and measured overall positron activities are almost equal (-3%) while the predicted activity originating from nitrogen is overestimated by almost a factor of two, possibly due to experimental noise. Based on the results obtained in this first feasibility study the great value of a combined radiotherapy-PET-CT unit is indicated in order to fully exploit the high activity signal from oxygen immediately after treatment and to avoid patient repositioning. With an RT-PET-CT unit a high signal could be collected even at a dose level of 2 Gy and the acquisition time for the PET could be reduced considerably. Real patient dose delivery verification by means of PET imaging seems to be
SU-E-T-612: Photonuclear Activation of Prosthetic Hips in Radiotherapy
Energy Technology Data Exchange (ETDEWEB)
Keehan, S; Taylor, M; Franich, R [RMIT University, Melbourne, VIC (Australia); Smith, R; Millar, J; Esser, M [William Buckland Radiotherapy Centre, Melbourne, VIC (Australia); Kron, T [Peter MacCallum Cancer Instit., Melbourne (Australia)
2015-06-15
Purpose: To measure the neutron induced activation of a prosthetic hip when exposed to an 18 MV radiotherapy linac beam to assess the potential dose to patients. Methods: A prosthetic hip (Thackray, UK) was placed in a water phantom and irradiated (both in-field and out-of-field) with an 18 MV linac beam. Gamma spectroscopy was used to identify the radioisotopes produced. Following the in-field irradiation where the induced activity is higher, high sensitivity lithium fluoride Thermoluminescence Dosimeters (TLD-100H) (Harshaw, USA) were placed on the surface to measure the dose which would be deposited to nearby tissue resulting from the induced radioactivity. Results: The radioisotopes produced in the hip prosthesis have been identified as {sup 5{sup 2}}V, {sup 5{sup 3}}Fe, and {sup 56}Mn which have half-lives of 3.74, 8.51 and minutes respectively. The 378 and 511 keV characteristic peaks of {sup 5{sup 3}}Fe do not appear in the spectra collected from hips irradiated in the out-of-field region. This isotope is produced by photonuclear interactions within the hip itself. {sup 52}V and {sup 56}Mn appear in spectra collected from hips irradiated either within the photon beam or in the nearby out-of-field region, implying that they are produced by incident neutron radiation produced in components of the linear accelerator.The integrated dose which would be deposited in the tissue immediately surrounding the hip after four hours (1.5 half-lives of the longest lived product) was measured as approximately 100 µGy, following a 10,000 MU irradiation of the prosthesis. A highly accurate measurement of the dose is challenging because of the irregular shape of the prosthesis. Conclusion: The cumulative dose measured at the surface of the hip is 0.0001% of the in-field dose, and is therefore negligible compared with the doses the patient receives as a consequence of their treatment.
Chromium and titanium isotopes produced in photonuclear reactions of vanadium, revisited
International Nuclear Information System (INIS)
Sakamoto, K.; Yoshida, M.; Kubota, Y.; Fukasawa, T.; Kunugise, A.; Hamajima, Y.; Shibata, S.; Fujiwara, I.
1988-10-01
Photonuclear production yields of 51 Ti and 51,49,48 Cr from 51 V were redetermined for bremsstrahlung end-point energies (E 0 ) of 30 to 1000 or 1050 MeV with an aid of radiochemical separation of Cr. The yield curves for 51 Ti, 51 Cr, 49 Cr and 48 Cr show a clear evidence for two components ; one for secondary-proton reaction at E 0 π ± and the other for photopion reaction, at E 0 > Q π ±, Q π ± being Q values for (γ,π + ) and (γ,π - xn)-reactions. The contributions of the secondary reactions for production of the Ti and Cr isotopes at E 0 > Q π ± were then estimated by fitting a calculated secondary yields to the observed ones at E 0 π ±, and found to be about 40, 20, 4 and 4 % for 51 Ti, 51 Cr, 49 Cr and 48 Cr, respectively, at E 0 = 400 to 1000 MeV. The calculation of the secondary yields was based on the excitation functions for 51 V(n,p) and (p,x'n) calculated with ALICE code and the reported photoneutron and photoproton spectra from 12 C and some other complex nuclei. The present results for 49 Cr are very close to the reported ones, while the present 48 Cr yields differ by a factor of about 50. For the 51 Ti and 51 Cr yields, there are some discrepancies between the present and reported ones. The yields corrected for the secondaries, in unit of μb/equivalent quantum, were unfolded into cross sections per photon, in unit of μb, as a function of monochromatic photon energy with the LOUHI-82 code. The results for the 51 Ti and 49 Cr are in disagreement in both the magnitude and shape with the theoretical predictions based on DWIA and PWIA. A Monte Carlo calculation does not reproduce the present result for the 49 Cr yield. (author)
Final Technical Report Project: Low-Energy Photonuclear Studies at HIGS and Lund
Energy Technology Data Exchange (ETDEWEB)
Feldman, Gerald [George Washington Univ., Washington, DC (United States)
2017-06-15
This report summarizes a program of low-energy photonuclear studies at MAX-Lab in Lund (Sweden) and at the High Intensity Gamma Source (HIGS) at Duke University. A major emphasis has been on Compton scattering from deuterium in order to determine the electric and magnetic polarizabilities of the neutron. The studies at Lund utilized unpolarized photons at Egamma = 62-115 MeV to measure differential cross sections. The studies at HIGS utilized polarized and unpolarized photon beams (both linear and circular) at Egamma < 90 MeV. Polarization observables will be exploited to improve our understanding of the electric and magnetic polarizabilities, and in particular, double-polarization observables (using polarized targets) will be measured in the future to provide new information about the spin polarizabilities of the nucleon. The MAX-Lab experiments (using unpolarized photons) focused on an approved PAC proposal for Compton scattering on the deuteron aimed at making a precise determination of the electromagnetic polarizabilities of the neutron. At MAX-Lab we had three of the largest NaI detectors in the world, each capable of ~2% energy resolution. We have completed our measurements in two separate tagged photon energy ranges which overlap each other (62-97 MeV and 90-115 MeV) and the results of these experiments have been published. The photon beam at the High Intensity Gamma Source (HIGS) has several distinct advantages that make it unique: (1) ultra-high photon flux, ultimately reaching 100 MHz, (2) 100% linearly polarized photon beam, as well as circular polarization, (3) monoenergetic beam, with ~2% energy resolution, and (4) extremely low-background beam environment. Exploiting the high flux and polarization capabilities of the HIGS photon beam is central in the series of experiments being performed at this facility. Very little data exist on Compton scattering using polarized photons. We will exploit clear sensitivities in the polarization observables to the
Energy Technology Data Exchange (ETDEWEB)
Boboshin, I N; Varlamov, A V; Varlamov, V V; Rudenko, D S; Stepanov, M E [D.V. Skobel' tsyn Scientific Research Institute for Nuclear Physics, M.V. Lomonosov Moscow State University, Centre for Photonuclear Experiments Data (Russian Federation)
2001-02-01
The nuclear databases which have been developed at the Centre for Photonuclear Experiments Data of the D.V. Skobel'tsyn Scientific Research Institute for Nuclear Physics, M.V. Lomonosov Moscow State University, and put on the Centre's web server, are presented. The possibilities for working with these databases on the Internet are described. (author)
International Nuclear Information System (INIS)
Boboshin, I.N.; Varlamov, A.V.; Varlamov, V.V.; Rudenko, D.S.; Stepanov, M.E.
2001-01-01
The nuclear databases which have been developed at the Centre for Photonuclear Experiments Data of the D.V. Skobel'tsyn Scientific Research Institute for Nuclear Physics, M.V. Lomonosov Moscow State University, and put on the Centre's web server, are presented. The possibilities for working with these databases on the Internet are described. (author)
Gudowska, I; Brahme, A; Andreo, P; Gudowski, W; Kierkegaard, J
1999-09-01
The absorbed dose due to photonuclear reactions in soft tissue, lung, breast, adipose tissue and cortical bone has been evaluated for a scanned bremsstrahlung beam of end point 50 MeV from a racetrack accelerator. The Monte Carlo code MCNP4B was used to determine the photon source spectrum from the bremsstrahlung target and to simulate the transport of photons through the treatment head and the patient. Photonuclear particle production in tissue was calculated numerically using the energy distributions of photons derived from the Monte Carlo simulations. The transport of photoneutrons in the patient and the photoneutron absorbed dose to tissue were determined using MCNP4B; the absorbed dose due to charged photonuclear particles was calculated numerically assuming total energy absorption in tissue voxels of 1 cm3. The photonuclear absorbed dose to soft tissue, lung, breast and adipose tissue is about (0.11-0.12)+/-0.05% of the maximum photon dose at a depth of 5.5 cm. The absorbed dose to cortical bone is about 45% larger than that to soft tissue. If the contributions from all photoparticles (n, p, 3He and 4He particles and recoils of the residual nuclei) produced in the soft tissue and the accelerator, and from positron radiation and gammas due to induced radioactivity and excited states of the nuclei, are taken into account the total photonuclear absorbed dose delivered to soft tissue is about 0.15+/-0.08% of the maximum photon dose. It has been estimated that the RBE of the photon beam of 50 MV acceleration potential is approximately 2% higher than that of conventional 60Co radiation.
International Nuclear Information System (INIS)
Gudowska, I.; Brahme, A.; Andreo, P.; Gudowski, W.; Kierkegaard, J.
1999-01-01
The absorbed dose due to photonuclear reactions in soft tissue, lung, breast, adipose tissue and cortical bone has been evaluated for a scanned bremsstrahlung beam of end point 50 MeV from a racetrack accelerator. The Monte Carlo code MCNP4B was used to determine the photon source spectrum from the bremsstrahlung target and to simulate the transport of photons through the treatment head and the patient. Photonuclear particle production in tissue was calculated numerically using the energy distributions of photons derived from the Monte Carlo simulations. The transport of photoneutrons in the patient and the photoneutron absorbed dose to tissue were determined using MCNP4B; the absorbed dose due to charged photonuclear particles was calculated numerically assuming total energy absorption in tissue voxels of 1 cm 3 . The photonuclear absorbed dose to soft tissue, lung, breast and adipose tissue is about (0.11-0.12)±0.05% of the maximum photon dose at a depth of 5.5 cm. The absorbed dose to cortical bone is about 45% larger than that to soft tissue. If the contributions from all photoparticles (n, p, 3 He and 4 He particles and recoils of the residual nuclei) produced in the soft tissue and the accelerator, and from positron radiation and gammas due to induced radioactivity and excited states of the nuclei, are taken into account the total photonuclear absorbed dose delivered to soft tissue is about 0.15±0.08% of the maximum photon dose. It has been estimated that the RBE of the photon beam of 50 MV acceleration potential is approximately 2% higher than that of conventional 60 Co radiation. (author)
DEFF Research Database (Denmark)
Gross, Fridolin; Green, Sara
2017-01-01
Systems biologists often distance themselves from reductionist approaches and formulate their aim as understanding living systems “as a whole”. Yet, it is often unclear what kind of reductionism they have in mind, and in what sense their methodologies offer a more comprehensive approach. To addre......-up”. Specifically, we point out that system-level properties constrain lower-scale processes. Thus, large-scale modeling reveals how living systems at the same time are more and less than the sum of the parts....
Borwein, J M; McPhedran, R C
2013-01-01
The study of lattice sums began when early investigators wanted to go from mechanical properties of crystals to the properties of the atoms and ions from which they were built (the literature of Madelung's constant). A parallel literature was built around the optical properties of regular lattices of atoms (initiated by Lord Rayleigh, Lorentz and Lorenz). For over a century many famous scientists and mathematicians have delved into the properties of lattices, sometimes unwittingly duplicating the work of their predecessors. Here, at last, is a comprehensive overview of the substantial body of
Statistical sums of strings on hyperellyptic surfaces
International Nuclear Information System (INIS)
Lebedev, D.; Morozov, A.
1987-01-01
Contributions of hyperellyptic surfaces to statistical sums of string theories are presented. Available results on hyperellyptic surface give the apportunity to check factorization of three-loop statsum. Some remarks on the vanishing statistical sum are presented
International Nuclear Information System (INIS)
Burmistenko, Yu.N.
1986-01-01
Technical, organizational and economical aspects as applied to the field of application of photonuclear methods of analysis of substance composition are considered. As for the technical aspect, the most important factors are nuclear-physical characteristics of the elements under determination and the elements composing the sample matrix. As for the organizational aspect, the governing factor in a number of cases is the availability of an irradiation device in the close vicinity of the analytical laboratory. Studying the technical and organizational aspects while choosing the proper method one can obtain the main source data to perform feasibility studies of a nuclear analytical complex with this or that activation source. Therefore, the economical aspect is governing for the choice of the method
Nested (inverse) binomial sums and new iterated integrals for massive Feynman diagrams
International Nuclear Information System (INIS)
Ablinger, Jakob; Schneider, Carsten; Bluemlein, Johannes; Raab, Clemens G.
2014-07-01
Nested sums containing binomial coefficients occur in the computation of massive operatormatrix elements. Their associated iterated integrals lead to alphabets including radicals, for which we determined a suitable basis. We discuss algorithms for converting between sum and integral representations, mainly relying on the Mellin transform. To aid the conversion we worked out dedicated rewrite rules, based on which also some general patterns emerging in the process can be obtained.
Nested (inverse) binomial sums and new iterated integrals for massive Feynman diagrams
Energy Technology Data Exchange (ETDEWEB)
Ablinger, Jakob; Schneider, Carsten [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation (RISC); Bluemlein, Johannes; Raab, Clemens G. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)
2014-07-15
Nested sums containing binomial coefficients occur in the computation of massive operatormatrix elements. Their associated iterated integrals lead to alphabets including radicals, for which we determined a suitable basis. We discuss algorithms for converting between sum and integral representations, mainly relying on the Mellin transform. To aid the conversion we worked out dedicated rewrite rules, based on which also some general patterns emerging in the process can be obtained.
Quintieri, Lina; Pia, Maria Grazia; Augelli, Mauro; Saracco, Paolo; Capogni, Marco; Guarnieri, Guido
2017-09-01
Photo-nuclear interactions are relevant in many research fields of both fundamental and applied physics and, for this reason, accurate Monte Carlo simulations of photo-nuclear interactions can provide a valuable and indispensable support in a wide range of applications (i.e from the optimisation of photo-neutron source target to the dosimetric estimation in high energy accelerator, etc). Unfortunately, few experimental photo-nuclear data are available above 100 MeV, so that, in the high energy range (from hundreds of MeV up to GeV scale), the code predictions are based on physical models. The aim of this work is to compare the predictions of relevant observables involving photon-nuclear interaction modelling, obtained with GEANT4 and FLUKA, to experimental data (if available), in order to assess the code estimation reliability, over a wide energy range. In particular, the comparison of the estimated photo-neutron yields and energy spectra with the experimental results of the n@BTF experiment (carried out at the Beam Test Facility of DaΦne collider, in Frascati, Italy) is here reported and discussed. Moreover, the preliminary results of the comparison of the cross sections used in the codes with the"evaluated' data recommended by the IAEA are also presented for some selected cases (W, Pb, Zn).
Extremum uncertainty product and sum states
Energy Technology Data Exchange (ETDEWEB)
Mehta, C L; Kumar, S [Indian Inst. of Tech., New Delhi. Dept. of Physics
1978-01-01
The extremum product states and sum states of the uncertainties in non-commuting observables have been examined. These are illustrated by two specific examples of harmonic oscillator and the angular momentum states. It shows that the coherent states of the harmonic oscillator are characterized by the minimum uncertainty sum <(..delta..q)/sup 2/>+<(..delta..p)/sup 2/>. The extremum values of the sums and products of the uncertainties of the components of the angular momentum are also obtained.
Decompounding random sums: A nonparametric approach
DEFF Research Database (Denmark)
Hansen, Martin Bøgsted; Pitts, Susan M.
Observations from sums of random variables with a random number of summands, known as random, compound or stopped sums arise within many areas of engineering and science. Quite often it is desirable to infer properties of the distribution of the terms in the random sum. In the present paper we...... review a number of applications and consider the nonlinear inverse problem of inferring the cumulative distribution function of the components in the random sum. We review the existing literature on non-parametric approaches to the problem. The models amenable to the analysis are generalized considerably...
International Nuclear Information System (INIS)
White, Morgan C.
2000-01-01
The fundamental motivation for the research presented in this dissertation was the need to development a more accurate prediction method for characterization of mixed radiation fields around medical electron accelerators (MEAs). Specifically, a model is developed for simulation of neutron and other particle production from photonuclear reactions and incorporated in the Monte Carlo N-Particle (MCNP) radiation transport code. This extension of the capability within the MCNP code provides for the more accurate assessment of the mixed radiation fields. The Nuclear Theory and Applications group of the Los Alamos National Laboratory has recently provided first-of-a-kind evaluated photonuclear data for a select group of isotopes. These data provide the reaction probabilities as functions of incident photon energy with angular and energy distribution information for all reaction products. The availability of these data is the cornerstone of the new methodology for state-of-the-art mutually coupled photon-neutron transport simulations. The dissertation includes details of the model development and implementation necessary to use the new photonuclear data within MCNP simulations. A new data format has been developed to include tabular photonuclear data. Data are processed from the Evaluated Nuclear Data Format (ENDF) to the new class ''u'' A Compact ENDF (ACE) format using a standalone processing code. MCNP modifications have been completed to enable Monte Carlo sampling of photonuclear reactions. Note that both neutron and gamma production are included in the present model. The new capability has been subjected to extensive verification and validation (V and V) testing. Verification testing has established the expected basic functionality. Two validation projects were undertaken. First, comparisons were made to benchmark data from literature. These calculations demonstrate the accuracy of the new data and transport routines to better than 25 percent. Second, the ability to
Energy Technology Data Exchange (ETDEWEB)
White, Morgan C. [Univ. of Florida, Gainesville, FL (United States)
2000-07-01
The fundamental motivation for the research presented in this dissertation was the need to development a more accurate prediction method for characterization of mixed radiation fields around medical electron accelerators (MEAs). Specifically, a model is developed for simulation of neutron and other particle production from photonuclear reactions and incorporated in the Monte Carlo N-Particle (MCNP) radiation transport code. This extension of the capability within the MCNP code provides for the more accurate assessment of the mixed radiation fields. The Nuclear Theory and Applications group of the Los Alamos National Laboratory has recently provided first-of-a-kind evaluated photonuclear data for a select group of isotopes. These data provide the reaction probabilities as functions of incident photon energy with angular and energy distribution information for all reaction products. The availability of these data is the cornerstone of the new methodology for state-of-the-art mutually coupled photon-neutron transport simulations. The dissertation includes details of the model development and implementation necessary to use the new photonuclear data within MCNP simulations. A new data format has been developed to include tabular photonuclear data. Data are processed from the Evaluated Nuclear Data Format (ENDF) to the new class ''u'' A Compact ENDF (ACE) format using a standalone processing code. MCNP modifications have been completed to enable Monte Carlo sampling of photonuclear reactions. Note that both neutron and gamma production are included in the present model. The new capability has been subjected to extensive verification and validation (V&V) testing. Verification testing has established the expected basic functionality. Two validation projects were undertaken. First, comparisons were made to benchmark data from literature. These calculations demonstrate the accuracy of the new data and transport routines to better than 25 percent. Second
Some Finite Sums Involving Generalized Fibonacci and Lucas Numbers
Directory of Open Access Journals (Sweden)
E. Kılıç
2011-01-01
Full Text Available By considering Melham's sums (Melham, 2004, we compute various more general nonalternating sums, alternating sums, and sums that alternate according to (−12+1 involving the generalized Fibonacci and Lucas numbers.
Where Does Latin "Sum" Come From?
Nyman, Martti A.
1977-01-01
The derivation of Latin "sum,""es(s),""est" from Indo-European "esmi,""est,""esti" involves methodological problems. It is claimed here that the development of "sum" from "esmi" is related to the origin of the variation "est-st" (less than"esti"). The study is primarily concerned with this process, but chronological suggestions are also made. (CHK)
Compound sums and their applications in finance
R. Helmers (Roelof); B. Tarigan
2003-01-01
textabstractCompound sums arise frequently in insurance (total claim size in a portfolio) and in accountancy (total error amount in audit populations). As the normal approximation for compound sums usually performs very badly, one may look for better methods for approximating the distribution of a
Gauss Sum Factorization with Cold Atoms
International Nuclear Information System (INIS)
Gilowski, M.; Wendrich, T.; Mueller, T.; Ertmer, W.; Rasel, E. M.; Jentsch, Ch.; Schleich, W. P.
2008-01-01
We report the first implementation of a Gauss sum factorization algorithm by an internal state Ramsey interferometer using cold atoms. A sequence of appropriately designed light pulses interacts with an ensemble of cold rubidium atoms. The final population in the involved atomic levels determines a Gauss sum. With this technique we factor the number N=263193
Shapley Value for Constant-sum Games
Khmelnitskaya, A.B.
2002-01-01
It is proved that Young's axiomatization for the Shapley value by marginalism, efficiency, and symmetry is still valid for the Shapley value defined on the class of nonnegative constant-sum games and on the entire class of constant-sum games as well. To support an interest to study the class of
Sums and products of sets and estimates of rational trigonometric sums in fields of prime order
Energy Technology Data Exchange (ETDEWEB)
Garaev, Mubaris Z [National Autonomous University of Mexico, Institute of Mathematics (Mexico)
2010-11-16
This paper is a survey of main results on the problem of sums and products of sets in fields of prime order and their applications to estimates of rational trigonometric sums. Bibliography: 85 titles.
Coloring sums of extensions of certain graphs
Directory of Open Access Journals (Sweden)
Johan Kok
2017-12-01
Full Text Available We recall that the minimum number of colors that allow a proper coloring of graph $G$ is called the chromatic number of $G$ and denoted $\\chi(G$. Motivated by the introduction of the concept of the $b$-chromatic sum of a graph the concept of $\\chi'$-chromatic sum and $\\chi^+$-chromatic sum are introduced in this paper. The extended graph $G^x$ of a graph $G$ was recently introduced for certain regular graphs. This paper furthers the concepts of $\\chi'$-chromatic sum and $\\chi^+$-chromatic sum to extended paths and cycles. Bipartite graphs also receive some attention. The paper concludes with patterned structured graphs. These last said graphs are typically found in chemical and biological structures.
A New Sum Analogous to Gauss Sums and Its Fourth Power Mean
Directory of Open Access Journals (Sweden)
Shaofeng Ru
2014-01-01
Full Text Available The main purpose of this paper is to use the analytic methods and the properties of Gauss sums to study the computational problem of one kind of new sum analogous to Gauss sums and give an interesting fourth power mean and a sharp upper bound estimate for it.
International Nuclear Information System (INIS)
Akbari, S.; Khosrovshahi, G.B.; Mofidi, A.
2010-07-01
Let D be a t-(v, k, λ) design and let N i (D), for 1 ≤ i ≤ t, be the higher incidence matrix of D, a (0, 1)-matrix of size (v/i) x b, where b is the number of blocks of D. A zero-sum flow of D is a nowhere-zero real vector in the null space of N 1 (D). A zero-sum k-flow of D is a zero-sum flow with values in {±,...,±(k-1)}. In this paper we show that every non-symmetric design admits an integral zero-sum flow, and consequently we conjecture that every non-symmetric design admits a zero-sum 5-flow. Similarly, the definition of zero-sum flow can be extended to N i (D), 1 ≤ i ≤ t. Let D = t-(v,k, (v-t/k-t)) be the complete design. We conjecture that N t (D) admits a zero-sum 3-flow and prove this conjecture for t = 2. (author)
Directory of Open Access Journals (Sweden)
Irene Machado
2008-11-01
Full Text Available Nem sempre os temas candentes da investigação, numa determinada área do conhecimento, são colocados de maneira orgânica e organizada para o conjunto dos pesquisadores que sobre eles se debruçam. Quase nunca as edições cientícas, que se propõem a torná-los acessíveis a seus leitores, conseguem harmonizá-los sem correr os riscos de aproximações indevidas. A única forma de não incorrer em equívocos perigosos é assumir a idiossincrasia do temário diversificado que constitui o campo em questão. O leitor que ora inicia seu diálogo com este sétimo número de Galáxia não deve tomar esse preâmbulo por alerta, mas sim como tentativa de a revista manter a coerência face a seu compromisso de ser porta-voz dos temas e problemas da comunicação e da cultura pelo prisma das teorias semióticas que orientam o olhar dos vários colaboradores que encontram neste espaço uma tribuna aberta ao trânsito das diferenças. Basta um relance pelo sumário desta edição para que tal armação possa ser confirmada. Os textos que constituem o Fórum, respeitadas as singularidades, tratam de temas que são caros para as abordagens da comunicação e da semiótica na cultura. Temos o privilégio de publicar o texto inédito em português de Jakob von Uexküll em que o autor apresenta sua teoria da Umwelt, caracterizando formulações da biossemiótica sobre o signi.cado do entorno ou do espaço circundante, que são valiosas para compreender a percepção, a interação, o contexto, a informação, os códigos em ambientes de semiose. De um outro lugar - aquele modulado pela lógica da linguagem - Lucrécia Ferrara perscruta o campo conceitual que entende o design não pelo viés da operatividade, mas como processo semiótico-cognitivo. A outra ponta deste que pode ser um triálogo nos é dado pela comunicologia de Vilém Flusser. Para Michael Hanke, Flusser foi um dos grandes teóricos a investigar a importância da mídia para os
Sum formulas for reductive algebraic groups
DEFF Research Database (Denmark)
Andersen, Henning Haahr; Kulkarni, Upendra
2008-01-01
\\supset V^1 \\cdots \\supset V^r = 0$. The sum of the positive terms in this filtration satisfies a well known sum formula. If $T$ denotes a tilting module either for $G$ or $U_q$ then we can similarly filter the space $\\Hom_G(V,T)$, respectively $\\Hom_{U_q}(V,T)$ and there is a sum formula for the positive...... terms here as well. We give an easy and unified proof of these two (equivalent) sum formulas. Our approach is based on an Euler type identity which we show holds without any restrictions on $p$ or $l$. In particular, we get rid of previous such restrictions in the tilting module case....
Structural relations between nested harmonic sums
International Nuclear Information System (INIS)
Bluemlein, J.
2008-07-01
We describe the structural relations between nested harmonic sums emerging in the description of physical single scale quantities up to the 3-loop level in renormalizable gauge field theories. These are weight w=6 harmonic sums. We identify universal basic functions which allow to describe a large class of physical quantities and derive their complex analysis. For the 3-loop QCD Wilson coefficients 35 basic functions are required, whereas a subset of 15 describes the 3-loop anomalous dimensions. (orig.)
Structural relations between nested harmonic sums
Energy Technology Data Exchange (ETDEWEB)
Bluemlein, J.
2008-07-15
We describe the structural relations between nested harmonic sums emerging in the description of physical single scale quantities up to the 3-loop level in renormalizable gauge field theories. These are weight w=6 harmonic sums. We identify universal basic functions which allow to describe a large class of physical quantities and derive their complex analysis. For the 3-loop QCD Wilson coefficients 35 basic functions are required, whereas a subset of 15 describes the 3-loop anomalous dimensions. (orig.)
International Nuclear Information System (INIS)
Dickens, J.K.
2001-01-01
The bremsstrahlung created by 150-MeV electrons impinging on a tantalum radiator was used to study photonuclear reactions on samples containing Be, C, Na, Cl and Ge. For Ge fifteen radioisotopes, ranging in half life between 2.6 min and 271 days, and in mass between 65 and 75, were obtained in sufficient amount to determine their yields quantitatively using known decay gamma-rays. Special equipment is described which was developed to create the bremsstrahlung using a beam-sharing mode, while minimizing the neutron flux on the sample. Relative production rates were determined. These were analyzed to provide absolute average cross sections for production of three reactions
Expansion around half-integer values, binomial sums, and inverse binomial sums
International Nuclear Information System (INIS)
Weinzierl, Stefan
2004-01-01
I consider the expansion of transcendental functions in a small parameter around rational numbers. This includes in particular the expansion around half-integer values. I present algorithms which are suitable for an implementation within a symbolic computer algebra system. The method is an extension of the technique of nested sums. The algorithms allow in addition the evaluation of binomial sums, inverse binomial sums and generalizations thereof
Experimental results of the betatron sum resonance
International Nuclear Information System (INIS)
Wang, Y.; Ball, M.; Brabson, B.
1993-06-01
The experimental observations of motion near the betatron sum resonance, ν x + 2ν z = 13, are presented. A fast quadrupole (Panofsky-style ferrite picture-frame magnet with a pulsed power supplier) producing a betatron tune shift of the order of 0.03 at rise time of 1 μs was used. This quadrupole was used to produce betatron tunes which jumped past and then crossed back through a betatron sum resonance line. The beam response as function of initial betatron amplitudes were recorded turn by turn. The correlated growth of the action variables, J x and J z , was observed. The phase space plots in the resonance frame reveal the features of particle motion near the nonlinear sum resonance region
Least square regularized regression in sum space.
Xu, Yong-Li; Chen, Di-Rong; Li, Han-Xiong; Liu, Lu
2013-04-01
This paper proposes a least square regularized regression algorithm in sum space of reproducing kernel Hilbert spaces (RKHSs) for nonflat function approximation, and obtains the solution of the algorithm by solving a system of linear equations. This algorithm can approximate the low- and high-frequency component of the target function with large and small scale kernels, respectively. The convergence and learning rate are analyzed. We measure the complexity of the sum space by its covering number and demonstrate that the covering number can be bounded by the product of the covering numbers of basic RKHSs. For sum space of RKHSs with Gaussian kernels, by choosing appropriate parameters, we tradeoff the sample error and regularization error, and obtain a polynomial learning rate, which is better than that in any single RKHS. The utility of this method is illustrated with two simulated data sets and five real-life databases.
On the Computation of Correctly Rounded Sums
DEFF Research Database (Denmark)
Kornerup, Peter; Lefevre, Vincent; Louvet, Nicolas
2012-01-01
This paper presents a study of some basic blocks needed in the design of floating-point summation algorithms. In particular, in radix-2 floating-point arithmetic, we show that among the set of the algorithms with no comparisons performing only floating-point additions/subtractions, the 2Sum...... algorithm introduced by Knuth is minimal, both in terms of number of operations and depth of the dependency graph. We investigate the possible use of another algorithm, Dekker's Fast2Sum algorithm, in radix-10 arithmetic. We give methods for computing, in radix 10, the floating-point number nearest...... the average value of two floating-point numbers. We also prove that under reasonable conditions, an algorithm performing only round-to-nearest additions/subtractions cannot compute the round-to-nearest sum of at least three floating-point numbers. Starting from an algorithm due to Boldo and Melquiond, we also...
Sums of two-dimensional spectral triples
DEFF Research Database (Denmark)
Christensen, Erik; Ivan, Cristina
2007-01-01
construct a sum of two dimensional modules which reflects some aspects of the topological dimensions of the compact metric space, but this will only give the metric back approximately. At the end we make an explicit computation of the last module for the unit interval in. The metric is recovered exactly...
Summing threshold logs in a parton shower
International Nuclear Information System (INIS)
Nagy, Zoltan; Soper, Davison E.
2016-05-01
When parton distributions are falling steeply as the momentum fractions of the partons increases, there are effects that occur at each order in α s that combine to affect hard scattering cross sections and need to be summed. We show how to accomplish this in a leading approximation in the context of a parton shower Monte Carlo event generator.
On Learning Ring-Sum-Expansions
DEFF Research Database (Denmark)
Fischer, Paul; Simon, H. -U.
1992-01-01
The problem of learning ring-sum-expansions from examples is studied. Ring-sum-expansions (RSE) are representations of Boolean functions over the base {#123;small infinum, (+), 1}#125;, which reflect arithmetic operations in GF(2). k-RSE is the class of ring-sum-expansions containing only monomials...... of length at most k:. term-RSE is the class of ring-sum-expansions having at most I: monomials. It is shown that k-RSE, k>or=1, is learnable while k-term-RSE, k>2, is not learnable if RPnot=NP. Without using a complexity-theoretical hypothesis, it is proven that k-RSE, k>or=1, and k-term-RSE, k>or=2 cannot...... be learned from positive (negative) examples alone. However, if the restriction that the hypothesis which is output by the learning algorithm is also a k-RSE is suspended, then k-RSE is learnable from positive (negative) examples only. Moreover, it is proved that 2-term-RSE is learnable by a conjunction...
Stark resonances: asymptotics and distributional Borel sum
International Nuclear Information System (INIS)
Caliceti, E.; Grecchi, V.; Maioli, M.
1993-01-01
We prove that the Stark effect perturbation theory of a class of bound states uniquely determines the position and the width of the resonances by Distributional Borel Sum. In particular the small field asymptotics of the width is uniquely related to the large order asymptotics of the perturbation coefficients. Similar results apply to all the ''resonances'' of the anharmonic and double well oscillators. (orig.)
Fibonacci Identities via the Determinant Sum Property
Spivey, Michael
2006-01-01
We use the sum property for determinants of matrices to give a three-stage proof of an identity involving Fibonacci numbers. Cassini's and d'Ocagne's Fibonacci identities are obtained at the ends of stages one and two, respectively. Catalan's Fibonacci identity is also a special case.
Summing threshold logs in a parton shower
Energy Technology Data Exchange (ETDEWEB)
Nagy, Zoltán [DESY,Notkestrasse 85, 22607 Hamburg (Germany); Soper, Davison E. [Institute of Theoretical Science, University of Oregon,Eugene, OR 97403-5203 (United States)
2016-10-05
When parton distributions are falling steeply as the momentum fractions of the partons increases, there are effects that occur at each order in α{sub s} that combine to affect hard scattering cross sections and need to be summed. We show how to accomplish this in a leading approximation in the context of a parton shower Monte Carlo event generator.
Demonstration of a Quantum Nondemolition Sum Gate
DEFF Research Database (Denmark)
Yoshikawa, J.; Miwa, Y.; Huck, Alexander
2008-01-01
The sum gate is the canonical two-mode gate for universal quantum computation based on continuous quantum variables. It represents the natural analogue to a qubit C-NOT gate. In addition, the continuous-variable gate describes a quantum nondemolition (QND) interaction between the quadrature...
Generalizations of some zero sum theorems
Indian Academy of Sciences (India)
Let G be an abelian group of order n, written additively. The Davenport constant D(G) is defined to be the smallest natural number t such that any sequence of length t over G has a non-empty subsequence whose sum is zero. Another combinatorial invariant E(G). (known as the EGZ constant) is the smallest natural number t ...
Succinct partial sums and fenwick trees
DEFF Research Database (Denmark)
Bille, Philip; Christiansen, Anders Roy; Prezza, Nicola
2017-01-01
We consider the well-studied partial sums problem in succint space where one is to maintain an array of n k-bit integers subject to updates such that partial sums queries can be efficiently answered. We present two succint versions of the Fenwick Tree â€“ which is known for its simplicity...... and practicality. Our results hold in the encoding model where one is allowed to reuse the space from the input data. Our main result is the first that only requires nk + o(n) bits of space while still supporting sum/update in O(logbn)/O(blogbn) time where 2 â‰¤ b â‰¤ log O(1)n. The second result shows how optimal...... time for sum/update can be achieved while only slightly increasing the space usage to nk + o(nk) bits. Beyond Fenwick Trees, the results are primarily based on bit-packing and sampling â€“ making them very practical â€“ and they also allow for simple optimal parallelization....
Geometric optimization and sums of algebraic functions
Vigneron, Antoine E.
2014-01-01
We present a new optimization technique that yields the first FPTAS for several geometric problems. These problems reduce to optimizing a sum of nonnegative, constant description complexity algebraic functions. We first give an FPTAS for optimizing such a sum of algebraic functions, and then we apply it to several geometric optimization problems. We obtain the first FPTAS for two fundamental geometric shape-matching problems in fixed dimension: maximizing the volume of overlap of two polyhedra under rigid motions and minimizing their symmetric difference. We obtain the first FPTAS for other problems in fixed dimension, such as computing an optimal ray in a weighted subdivision, finding the largest axially symmetric subset of a polyhedron, and computing minimum-area hulls.
Second harmonic generation and sum frequency generation
International Nuclear Information System (INIS)
Pellin, M.J.; Biwer, B.M.; Schauer, M.W.; Frye, J.M.; Gruen, D.M.
1990-01-01
Second harmonic generation and sum frequency generation are increasingly being used as in situ surface probes. These techniques are coherent and inherently surface sensitive by the nature of the mediums response to intense laser light. Here we will review these two techniques using aqueous corrosion as an example problem. Aqueous corrosion of technologically important materials such as Fe, Ni and Cr proceeds from a reduced metal surface with layer by layer growth of oxide films mitigated by compositional changes in the chemical makeup of the growing film. Passivation of the metal surface is achieved after growth of only a few tens of atomic layers of metal oxide. Surface Second Harmonic Generation and a related nonlinear laser technique, Sum Frequency Generation have demonstrated an ability to probe the surface composition of growing films even in the presence of aqueous solutions. 96 refs., 4 figs
Disjoint sum forms in reliability theory
Directory of Open Access Journals (Sweden)
B. Anrig
2014-01-01
Full Text Available The structure function f of a binary monotone system is assumed to be known and given in a disjunctive normal form, i.e. as the logical union of products of the indicator variables of the states of its subsystems. Based on this representation of f, an improved Abraham algorithm is proposed for generating the disjoint sum form of f. This form is the base for subsequent numerical reliability calculations. The approach is generalized to multivalued systems. Examples are discussed.
A 2-categorical state sum model
Energy Technology Data Exchange (ETDEWEB)
Baratin, Aristide, E-mail: abaratin@uwaterloo.ca [Department of Applied Mathematics, University of Waterloo, 200 University Ave W, Waterloo, Ontario N2L 3G1 (Canada); Freidel, Laurent, E-mail: lfreidel@perimeterinstitute.ca [Perimeter Institute for Theoretical Physics, 31 Caroline Str. N, Waterloo, Ontario N2L 2Y5 (Canada)
2015-01-15
It has long been argued that higher categories provide the proper algebraic structure underlying state sum invariants of 4-manifolds. This idea has been refined recently, by proposing to use 2-groups and their representations as specific examples of 2-categories. The challenge has been to make these proposals fully explicit. Here, we give a concrete realization of this program. Building upon our earlier work with Baez and Wise on the representation theory of 2-groups, we construct a four-dimensional state sum model based on a categorified version of the Euclidean group. We define and explicitly compute the simplex weights, which may be viewed a categorified analogue of Racah-Wigner 6j-symbols. These weights solve a hexagon equation that encodes the formal invariance of the state sum under the Pachner moves of the triangulation. This result unravels the combinatorial formulation of the Feynman amplitudes of quantum field theory on flat spacetime proposed in A. Baratin and L. Freidel [Classical Quantum Gravity 24, 2027–2060 (2007)] which was shown to lead after gauge-fixing to Korepanov’s invariant of 4-manifolds.
2013-08-08
... systems and would reduce the systemic and administrative burdens on market participants by avoiding the... Arca rules rather than having the Exchange enforce NYSE Arca rules. In sum, the Exchange believes that...
2013-08-08
... reduce the systemic and administrative burdens on market participants by avoiding the need for... enforce NYSE Arca rules, as the NYSE would do under its current rule. In sum, the Exchange believes that...
International Nuclear Information System (INIS)
Abdelsalam, A.; Kamel, S.; Abdel-Waged, Kh.; Fashed, N.
2005-01-01
Production of multi-hydrogen (mH) isotopes in the spallation of 200A GeV sulphur projectile using nuclear emulsion is reported. Yield of mH isotopes is studied and compared with that of the lowest energy (3.7A GeV) data. The two-source emission picture is used to describe the transverse momentum (P T ) distribution of mH isotopes (with and without the effect of 32 S (γ,p) 31 P channel). The Rayleigh type P T -distribution seems to be in agreement with the corresponding experimental data. The contributions of low and high temperature emission sources show a dependence on the photonuclear processes. (author)
International Nuclear Information System (INIS)
Tran Duc Thiep; Truong Thi An; Phan Viet Cuong; Nguyen The Vinh
2012-01-01
We have determined the isomeric ratios in 130 Ba(γ, n) 129m,g Ba, 132 Ba(γ, n) 131m,g Ba and 134 Ba(γ, n) 133m,g Ba photonuclear reactions of natural barium induced by bremsstrahlungs with end-point energies in the giant dipole resonance region. The investigated samples were irradiated at electron accelerator Microtron MT-25 of the Flerov Laboratory of Nuclear Reaction, Joint Institute for Nuclear Research, Dubna, Russia. The gamma spectra of the samples irradiated were measured with spectroscopic system consisting of 8192 channel analyzer and high-energy resolution (180 keV at gamma ray 1332 keV of 60 Co) HP(Ge) semiconductor detector Canberra. The GENIE2000 (Canberra) computer program was used for data processing. The results were discussed and compared with those of other authors. (author)
Remark on the computation of mode sums
International Nuclear Information System (INIS)
Allen, Theodore J.; Olsson, M. G.; Schmidt, Jeffrey R.
2000-01-01
The computation of mode sums of the types encountered in basic quantum field theoretic applications is addressed with an emphasis on their expansions into functions of distance that can be interpreted as potentials. We show how to regularize and calculate the Casimir energy for the continuum Nambu-Goto string with massive ends as well as for the discrete Isgur-Paton non-relativistic string with massive ends. As an additional example, we examine the effect on the interquark potential of a constant Kalb-Ramond field strength interacting with a QCD string. (c) 2000 The American Physical Society
DEFF Research Database (Denmark)
Triantafillou, Peter
2017-01-01
Supreme audit institutions (SAIs) are fundamental institutions in liberal democracies as they enable control of the exercise of state power. In order to maintain this function, SAIs must enjoy a high level of independence. Moreover, SAIs are increasingly expected to be also relevant for government...... and the execution of its policies by way of performance auditing. This article examines how and why the performance auditing of the Danish SAI pursues independence and relevance. It is argued that, in general, the simultaneous pursuit of independence and relevance is highly challenging and amounts to a zero-sum or...
Statistical sum of bosonic string, compactified on an orbifold
International Nuclear Information System (INIS)
Morozov, A.; Ol'shanetskij, M.
1986-01-01
Expression for statistical sum of bosonic string, compactified on a singular orbifold, is presented. All the information about the orbifold is encoded the specific combination of theta-functions, which the statistical sum is expressed through
A new generalization of Hardy–Berndt sums
Indian Academy of Sciences (India)
4,11,18]. Berndt and Goldberg [4] found analytic properties of these sums and established infinite trigonometric series representations for them. The most important properties of Hardy–. Berndt sums are reciprocity theorems due to Berndt [3] ...
7 CFR 42.132 - Determining cumulative sum values.
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Determining cumulative sum values. 42.132 Section 42... Determining cumulative sum values. (a) The parameters for the on-line cumulative sum sampling plans for AQL's... 3 1 2.5 3 1 2 1 (b) At the beginning of the basic inspection period, the CuSum value is set equal to...
Deriving the Normalized Min-Sum Algorithm from Cooperative Optimization
Huang, Xiaofei
2006-01-01
The normalized min-sum algorithm can achieve near-optimal performance at decoding LDPC codes. However, it is a critical question to understand the mathematical principle underlying the algorithm. Traditionally, people thought that the normalized min-sum algorithm is a good approximation to the sum-product algorithm, the best known algorithm for decoding LDPC codes and Turbo codes. This paper offers an alternative approach to understand the normalized min-sum algorithm. The algorithm is derive...
Extremal extensions for the sum of nonnegative selfadjoint relations
Hassi, Seppo; Sandovici, Adrian; De Snoo, Henk; Winkler, Henrik
2007-01-01
The sum A + B of two nonnegative selfadjoint relations (multivalued operators) A and B is a nonnegative relation. The class of all extremal extensions of the sum A + B is characterized as products of relations via an auxiliary Hilbert space associated with A and B. The so-called form sum extension
Moments of the weighted sum-of-digits function | Larcher ...
African Journals Online (AJOL)
The weighted sum-of-digits function is a slight generalization of the well known sum-of-digits function with the difference that here the digits are weighted by some weights. So for example in this concept also the alternated sum-of-digits function is included. In this paper we compute the first and the second moment of the ...
7 CFR 1726.205 - Multiparty lump sum quotations.
2010-01-01
... 7 Agriculture 11 2010-01-01 2010-01-01 false Multiparty lump sum quotations. 1726.205 Section 1726....205 Multiparty lump sum quotations. The borrower or its engineer must contact a sufficient number of... basis of written lump sum quotations, the borrower will select the supplier or contractor based on the...
Scattering and; Delay, Scale, and Sum Migration
Energy Technology Data Exchange (ETDEWEB)
Lehman, S K
2011-07-06
How do we see? What is the mechanism? Consider standing in an open field on a clear sunny day. In the field are a yellow dog and a blue ball. From a wave-based remote sensing point of view the sun is a source of radiation. It is a broadband electromagnetic source which, for the purposes of this introduction, only the visible spectrum is considered (approximately 390 to 750 nanometers or 400 to 769 TeraHertz). The source emits an incident field into the known background environment which, for this example, is free space. The incident field propagates until it strikes an object or target, either the yellow dog or the blue ball. The interaction of the incident field with an object results in a scattered field. The scattered field arises from a mis-match between the background refractive index, considered to be unity, and the scattering object refractive index ('yellow' for the case of the dog, and 'blue' for the ball). This is also known as an impedance mis-match. The scattering objects are referred to as secondary sources of radiation, that radiation being the scattered field which propagates until it is measured by the two receivers known as 'eyes'. The eyes focus the measured scattered field to form images which are processed by the 'wetware' of the brain for detection, identification, and localization. When time series representations of the measured scattered field are available, the image forming focusing process can be mathematically modeled by delayed, scaled, and summed migration. This concept of optical propagation, scattering, and focusing have one-to-one equivalents in the acoustic realm. This document is intended to present the basic concepts of scalar scattering and migration used in wide band wave-based remote sensing and imaging. The terms beamforming and (delayed, scaled, and summed) migration are used interchangeably but are to be distinguished from the narrow band (frequency domain) beamforming to determine
Determination of the Bjorken Sum and Strong Coupling from Polarized Structure Functions
Altarelli, Guido; Forte, Stefano; Ridolfi, G; Altarelli, Guido; Ball, Richard D.; Forte, Stefano; Ridolfi, Giovanni
1997-01-01
We present a NLO perturbative analysis of all available data on the polarized structure function g_1(x,Q^2) with the aim of making a quantitative test of the validity of the Bjorken sum rule, of measuring \\alpha_s, and of deriving helicity fractions. We take particular care over the small x extrapolation, since it is now known that Regge behaviour is unreliable at perturbative scales. For fixed \\alpha_s we find that if all the most recent data are included g_A=1.18\\pm0.09, confirming the Bjorken sum rule at the 8% level. We further show that the value of \\alpha_s is now reasonably well constrained by scaling violations in the structure function data, despite the fact that it cannot yet be reliably fixed by the value of the Bjorken sum: our final result is \\alpha_s(m_Z) = 0.120+0.010-0.008. We also confirm earlier indications of a sizeable positive gluon polarization in the nucleon.
Evans, Philip; Wolf, Bob
2005-01-01
Corporate leaders seeking to boost growth, learning, and innovation may find the answer in a surprising place: the Linux open-source software community. Linux is developed by an essentially volunteer, self-organizing community of thousands of programmers. Most leaders would sell their grandmothers for workforces that collaborate as efficiently, frictionlessly, and creatively as the self-styled Linux hackers. But Linux is software, and software is hardly a model for mainstream business. The authors have, nonetheless, found surprising parallels between the anarchistic, caffeinated, hirsute world of Linux hackers and the disciplined, tea-sipping, clean-cut world of Toyota engineering. Specifically, Toyota and Linux operate by rules that blend the self-organizing advantages of markets with the low transaction costs of hierarchies. In place of markets' cash and contracts and hierarchies' authority are rules about how individuals and groups work together (with rigorous discipline); how they communicate (widely and with granularity); and how leaders guide them toward a common goal (through example). Those rules, augmented by simple communication technologies and a lack of legal barriers to sharing information, create rich common knowledge, the ability to organize teams modularly, extraordinary motivation, and high levels of trust, which radically lowers transaction costs. Low transaction costs, in turn, make it profitable for organizations to perform more and smaller transactions--and so increase the pace and flexibility typical of high-performance organizations. Once the system achieves critical mass, it feeds on itself. The larger the system, the more broadly shared the knowledge, language, and work style. The greater individuals' reputational capital, the louder the applause and the stronger the motivation. The success of Linux is evidence of the power of that virtuous circle. Toyota's success is evidence that it is also powerful in conventional companies.