Nucleon axial form factor from lattice QCD
International Nuclear Information System (INIS)
Liu, K.F.; Dong, S.J.; Draper, T.; Wu, J.M.; Wilcox, W.
1994-01-01
Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both the point-split and local currents. They are obtained on a quenched 16 3 x24 lattice at β=6.0 with Wilson fermions for a range of quark masses from strange to twice the charm mass. For each quark mass, we find that the axial form factor falls off slower than the corresponding proton electric form factor. Results extrapolated to the chiral limit show that the q 2 dependence of the axial form factor agrees quite well with experiment. The axial vector coupling constant g A calculated for the point-split and local currents is 1.20±0.11 and 1.18±0.11. The central values are 4% and 6% smaller than the experimental value of 1.254, respectively. We also consider the large ma correction and renormalization for the axial vector current of heavy quarks
Vector and axial nucleon form factors: A duality constrained parameterization
International Nuclear Information System (INIS)
Bodek, A.; Avvakumov, S.; Bradford, R.; Budd, H.
2008-01-01
We present new parameterizations of vector and axial nucleon form factors. We maintain an excellent descriptions of the form factors at low momentum transfers, where the spatial structure of the nucleon is important, and use the Nachtman scaling variable ξ to relate elastic and inelastic form factors and impose quark-hadron duality constraints at high momentum transfers where the quark structure dominates. We use the new vector form factors to re-extract updated values of the axial form factor from neutrino experiments on deuterium. We obtain an updated world average value from ν μ d and pion electroproduction experiments of M A =1.014±0.014 GeV/c 2 . Our parameterizations are useful in modeling neutrino interactions at low energies (e.g. for neutrino oscillations experiments). The predictions for high momentum transfers can be tested in the next generation electron and neutrino scattering experiments. (orig.)
The Nucleon Axial Form Factor and Staggered Lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Meyer, Aaron Scott [Chicago U.
2017-01-01
The study of neutrino oscillation physics is a major research goal of the worldwide particle physics program over the upcoming decade. Many new experiments are being built to study the properties of neutrinos and to answer questions about the phenomenon of neutrino oscillation. These experiments need precise theoretical cross sections in order to access fundamental neutrino properties. Neutrino oscillation experiments often use large atomic nuclei as scattering targets, which are challenging for theorists to model. Nuclear models rely on free-nucleon amplitudes as inputs. These amplitudes are constrained by scattering experiments with large nuclear targets that rely on the very same nuclear models. The work in this dissertation is the rst step of a new initiative to isolate and compute elementary amplitudes with theoretical calculations to support the neutrino oscillation experimental program. Here, the eort focuses on computing the axial form factor, which is the largest contributor of systematic error in the primary signal measurement process for neutrino oscillation studies, quasielastic scattering. Two approaches are taken. First, neutrino scattering data on a deuterium target are reanalyzed with a model-independent parametrization of the axial form factor to quantify the present uncertainty in the free-nucleon amplitudes. The uncertainties on the free-nucleon cross section are found to be underestimated by about an order of magnitude compared to the ubiquitous dipole model parametrization. The second approach uses lattice QCD to perform a rst-principles computation of the nucleon axial form factor. The Highly Improved Staggered Quark (HISQ) action is employed for both valence and sea quarks. The results presented in this dissertation are computed at physical pion mass for one lattice spacing. This work presents a computation of the axial form factor at zero momentum transfer, and forms the basis for a computation of the axial form factor momentum dependence
Calculation of the Nucleon Axial Form Factor Using Staggered Lattice QCD
Energy Technology Data Exchange (ETDEWEB)
Meyer, Aaron S. [Fermilab; Hill, Richard J. [Perimeter Inst. Theor. Phys.; Kronfeld, Andreas S. [Fermilab; Li, Ruizi [Indiana U.; Simone, James N. [Fermilab
2016-10-14
The nucleon axial form factor is a dominant contribution to errors in neutrino oscillation studies. Lattice QCD calculations can help control theory errors by providing first-principles information on nucleon form factors. In these proceedings, we present preliminary results on a blinded calculation of $g_A$ and the axial form factor using HISQ staggered baryons with 2+1+1 flavors of sea quarks. Calculations are done using physical light quark masses and are absolutely normalized. We discuss fitting form factor data with the model-independent $z$ expansion parametrization.
Axial-vector form factors of the nucleon from lattice QCD
Gupta, Rajan; Jang, Yong-Chull; Lin, Huey-Wen; Yoon, Boram; Bhattacharya, Tanmoy; Precision Neutron Decay Matrix Elements Pndme Collaboration
2017-12-01
We present results for the form factors of the isovector axial vector current in the nucleon state using large scale simulations of lattice QCD. The calculations were done using eight ensembles of gauge configurations generated by the MILC collaboration using the HISQ action with 2 +1 +1 dynamical flavors. These ensembles span three lattice spacings a ≈0.06 , 0.09, and 0.12 fm and light-quark masses corresponding to the pion masses Mπ≈135 , 225, and 310 MeV. High-statistics estimates allow us to quantify systematic uncertainties in the extraction of GA(Q2) and the induced pseudoscalar form factor G˜P(Q2). We perform a simultaneous extrapolation in the lattice spacing, lattice volume and light-quark masses of the axial charge radius rA data to obtain physical estimates. Using the dipole ansatz to fit the Q2 behavior we obtain rA|dipole=0.49 (3 ) fm , which corresponds to MA=1.39 (9 ) GeV , and is consistent with MA=1.35 (17 ) GeV obtained by the miniBooNE collaboration. The estimate obtained using the z -expansion is rA|z -expansion =0.46(6) fm, and the combined result is rA|combined=0.48(4 ) fm. Analysis of the induced pseudoscalar form factor G ˜P(Q2) yields low estimates for gP* and gπ NN compared to their phenomenological values. To understand these, we analyze the partially conserved axial current (PCAC) relation by also calculating the pseudoscalar form factor. We find that these low values are due to large deviations in the PCAC relation between the three form factors, and in the pion-pole dominance hypothesis.
Nucleon axial form factors using Nf=2 twisted mass fermions with a physical value of the pion mass
Alexandrou, C.; Constantinou, M.; Hadjiyiannakou, K.; Jansen, K.; Kallidonis, C.; Koutsou, G.; Vaquero Aviles-Casco, A.
2017-09-01
We present results on the nucleon axial and induced pseudoscalar form factors using an ensemble of two degenerate twisted mass clover-improved fermions with mass yielding a pion mass of mπ=130 MeV . We evaluate the isovector and the isoscalar, as well as the strange and the charm axial form factors. The disconnected contributions are evaluated using recently developed methods that include deflation of the lower eigenstates, allowing us to extract the isoscalar, strange, and charm axial form factors. We find that the disconnected quark loop contributions are nonzero and particularly large for the induced pseudoscalar form factor.
Strangeness Vector and Axial-Vector Form Factors of the Nucleon
Directory of Open Access Journals (Sweden)
Pate Stephen
2014-03-01
Full Text Available A revised global fit of electroweak ep and vp elastic scattering data has been performed, with the goal of determining the strange quark contribution to the vector and axial-vector form factors of the nucleon in the momentum-transfer range 0 < Q2 < 1 GeV2. The two vector (electric and magnetic form factors GsE(Q2 and GsM(Q2 are strongly constrained by ep elastic scattering data, while the major source of information on the axial-vector form factor GsA(Q2 is vp scattering data. Combining the two kinds of data into a single global fit makes possible additional precision in the determination of these form factors, and provides a unique way to determine the strange quark contribution to the nucleon spin, ΔS , independently of leptonic deep-inelastic scattering. The fit makes use of data from the BNL-E734, SAMPLE, HAPPEx, G0, and PVA4 experiments; we will also compare the result of the fit with recent data from MiniBooNE, and anticipate how this fit can be improved when new data from MicroBooNE become available.
Determination of the axial-vector form factor in the radiative decay of the pion
International Nuclear Information System (INIS)
Ortendahl, D.A.
1976-12-01
The branching ratio for the decay π → eνγ was measured in a counter experiment in which the e + was detected in a magnetic spectrometer and the γ-ray in a lead glass hodoscope. The number of observed events is 226.2 +- 22.4. The branching ratio into the phase space with electron momentum above 56 MeV/c and the electron/photon opening angle greater than 132 0 is found to be (5.6 +- 0.7) x 10 -8 . From the measured branching ratio one determines γ, the ratio of the axial vector to vector form factor. The vector form factor is computed using CVC and the π 0 lifetime. For T/sub π/ 0 = 0.828 x 10 -16 sec, γ = 0.44 +- 0.12 or γ = --2.36 +- 0.12 is obtained. A comparison between the measured values of γ and various theories is made
Recoil of the pion-surrounded nucleon bag and axial form factors
International Nuclear Information System (INIS)
Klabucar, D.; Picek, I.
1984-03-01
A recent method of boosting the bag is extended to the pion-surrounded nucleon bag and developed for the calculation of low-energy nucleon form factors. The usefulness of the method is illustrated by the induced pseudoscalar form factor where both the inclusion of the pion field and the non-vanishing momentum transfer are necessary. (Auth.)
Alexandrou, Constantia; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Jansen, Karl; Kallidonis, Christos; Koutsou, Giannis; Vaquero Avilés-Casco, Alejandro
2018-03-01
We present results on the isovector and isoscalar nucleon axial form factors including disconnected contributions, using an ensemble of Nf = 2 twisted mass cloverimproved Wilson fermions simulated with approximately the physical value of the pion mass. The light disconnected quark loops are computed using exact deflation, while the strange and the charm quark loops are evaluated using the truncated solver method. Techniques such as the summation and the two-state fits have been employed to access ground-state dominance.
Energy Technology Data Exchange (ETDEWEB)
Schaub, John [New Mexico State Univ., Las Cruces, NM (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2010-07-01
We studied the strange contributions to the elastic vector and axial form factors of the nucleon using all available elastic electroweak scattering data. Specifically, we combine elastic nu-p and nubar-p scattering cross-section data from the Brookhaven E734 experiment with elastic ep and quasi-elastic ed and e-^{4}He scattering parity-violating asymmetry data from the SAMPLE, HAPPEx, PVA4 and G0 experiments. We not only determined these form factors at individual values of momentum-transfer (Q^{2}), as other groups have done recently, but also fit the Q^{2}-dependence of these form factors using simple functional forms. I present an overview of the G^{0} backward-angle experiment as well as the results of these fits using existing data, along with some expectations of how we can improve our knowledge of these form factors if the MicroBooNE collaboration completes their experiment.
Axial stress corrosion cracking forming method to metal tube
International Nuclear Information System (INIS)
Araki, Kumiko
1998-01-01
Generally, it is more difficult in a metal tube, to intentionally cause a stress corrosion cracking in axial direction than in circumferential direction. In the present invention, a bevel is formed on a metal tube and welding is conducted in circumferential direction along the bevel, and welding is conducted in axial direction partially to the portion welded in circumferential direction. Namely, a bevel is formed in circumferential direction to an abutting portion of thick-walled metal tubes with each other, welding is conducted in circumferential direction along the bevel, and welding is conducted in axial direction partially to a portion welded in circumferential direction. With such procedures, since tensile stress in the circumferential direction is increased partially at a portion welded in axial direction, stress corrosion cracking is caused in axial direction at the portion. Then, stress corrosion cracking in axial direction can thus be formed on the thick-walled metal tube. (N.H.)
Experimental Study of Axially Tension Cold Formed Steel Channel Members
Apriani, Widya; Lubis, Fadrizal; Angraini, Muthia
2017-12-01
Experimental testing is commonly used as one of the steps to determine the cause of the collapse of a building structure. The collapse of structures can be due to low quality materials. Although material samples have passed laboratory tests and the existing technical specifications have been met but there may be undetected defects and known material after failure. In this paper will be presented Experimental Testing of Axially Tension Cold Formed Steel Channel Members to determine the cause of the collapse of a building roof truss x in Pekanbaru. Test of tensile strength material cold formed channel sections was performed to obtain the main characteristics of Cold Formed steel material, namely ultimate tensile strength loads that can be held by members and the yield stress possessed by channel sections used in construction. Analysis of axially tension cold formed steel channel section presents in this paper was conducted through experimental study based on specificationsAnnualBook of ASTM Standards: Metal Test methods and Analitical Procedures, Section 3 (1991). The result of capacity loads experimental test was compared with design based on SNI 03-7971-2013standard of Indonesia for the design of cold formed steel structural members. The results of the yield stress of the material will be seen against the minimum allowable allowable stress range. After the test, the percentace of ultimate axial tension capacity theory has a result that is 16.46% larger than the ultimate axial tension capacity experimental. When compared with the load that must be borne 5.673 kN/m it can be concluded that 2 specimens do not meet. Yield stress of member has fulfilled requirement that wass bigger than 550 MPa. Based on the curve obtained ultimate axial tension capacity theory, results greater than experimental. The greatest voltage value (fu) is achieved under the same conditions as its yield stress. For this specimen with a melting voltage value fy = 571.5068 MPa has fulfilled the
Electroweak form factors of the Skyrmion
International Nuclear Information System (INIS)
Braaten, E.; Sze-Man Tse; Willcox, C.
1986-01-01
The electroweak form factors of baryons are studied in the semiclassical approximation to the Skyrme model. General expressions for the form factors are given for arbitrary choices of the Skyrme-model Lagrangian. They are applied to the original two-parameter Skyrme model to compute the electric, magnetic, and axial-vector form factors of the nucleon and the electromagnetic nucleon-Δ transition form factors. The dependence of the form factors on the momentum transfer is compared with phenomenological dipole parametrizations
International Nuclear Information System (INIS)
Bonnet, Frederic D.R.; Edwards, Robert G.; Felming, George T.; Randal Lewis; David Richards
2003-01-01
We have started a program to compute the electromagnetic form factors of mesons. We discuss the techniques used to compute the pion form factor and present preliminary results computed with domain wall valence fermions on MILC asqtad lattices, as well as Wilson fermions on quenched lattices. These methods can easily be extended to rho-to-gamma-pi transition form factors
Nucleon form factors in the projected linear chiral soliton model
International Nuclear Information System (INIS)
Alberto, P.; Coimbra Univ.; Coimbra Univ.; Ruiz Arriola, E.; Gruemmer, F.; Fiolhais, M.; Urbano, J.N.; Coimbra Univ.; Goeke, K.; Bochum Univ.
1988-01-01
Electromagnetic and axial form factors of the nucleon are evaluated using the lagrangian of the linear chiral soliton model. To this end angular momentum and isospin projected mean field solutions are determined variationally assuming valence quarks and pions in generalized hedgehog configurations. With the proper pion decay constant and after fitting the quark-meson coupling constant to the nucleon energy both proton and neutron charge form factors are reproduced as well as the slope of the magnetic ones. The axial form factor agrees less well with experiment. The pion form factor can be approximated by a monopole with a cut-off mass of 690 MeV. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Ryong Ji, C.; Pang, A.; Szczepaniak, A. [North Carolina State Univ., Raleigh, NC (United States)
1994-04-01
It is pointed out that the correct criterion to define the legal PQCD contribution to the exclusive processes in the lightcone perturbative expansion should be based on the large off-shellness of the lightcone energy in the intermediate states. In the lightcone perturbative QCD calculation of the pion form factor, the authors find that the legal PQCD contribution defined by the lightcone energy cut saturates in the smaller Q{sup 2} region compared to that defined by the gluon four-momentum square cut. This is due to the contribution by the highly off-energy-shell gluons in the end point regions of the phase space, indicating that the gluon four-momentum-square cut may have cut too much to define the legal PQCD.
Nucleon Electromagnetic Form Factors
Energy Technology Data Exchange (ETDEWEB)
Marc Vanderhaeghen; Charles Perdrisat; Vina Punjabi
2007-10-01
There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has greatly improved by performing double polarization experiments, in comparison with previous unpolarized data. Here we review the experimental data base in view of the new results for the proton, and neutron, obtained at JLab, MAMI, and MIT-Bates. The rapid evolution of phenomenological models triggered by these high-precision experiments will be discussed, including the recent progress in the determination of the valence quark generalized parton distributions of the nucleon, as well as the steady rate of improvements made in the lattice QCD calculations.
Factors influencing surgical complications of intra-axial brain tumours.
Brell, M; Ibáñez, J; Caral, L; Ferrer, E
2000-01-01
Extensive surgical resection remains nowadays the best treatment available for most intra-axial brain tumours. However, postoperative sequelae can outweigh the potential benefits of surgery. The goal of this study has been to review the results of this treatment in our Department in order to quantify morbidity and mortality and determine predictive risk factors for each patient. We report a retrospective study of 200 patients submitted to a craniotomy for intra-axial brain tumours including gliomas and metastases. Postoperative major complications are analysed and related to different variables. An exhaustive review of the literature concerning the main controversial points about primary and metastatic brain tumours surgery is done. The overall major complication rate was 27.5%, with neurological complications being the most frequently encountered. We did not find a statistically significant relation between them and the grade of eloquence of the tumoural area. Infratentorial tumour location, previous radiotherapy and reoperations were factors strongly related to the incidence of regional complications. Age over 60 and severe concomitant disease were risk factors for systemic complications. The results from published series concerning surgical complications after craniotomies for brain tumours are not comparable because of the lack of homogeneity between them. The knowledge of the complications rate in each particular neurosurgical department turns out essentially to provide the patient with tailored information about risks before surgery.
Nonleptonic B decays to axial-vector mesons and factorization
International Nuclear Information System (INIS)
Laporta, V.; Nardulli, G.; Pham, T. N.
2006-01-01
We present an analysis of two-body B decays with a pseudoscalar (P) and an axial-vector meson (A) in the final state using factorization. We employ as inputs a limited number of experimental data, i.e. results for the B→K 1 γ, and B→K*γ radiative decays and the branching ratios for B→πρ, πK*, Kρ, Kπ nonleptonic decays. In this way we are able to compare our predictions with recent data from the Belle and BABAR collaborations on B→a 1 π and make predictions on several other B→PA decay channels, which might be used as a guide for experimental researches and as tests of factorization
Treatment with tumor necrosis factor inhibitors in axial spondyloarthritis
DEFF Research Database (Denmark)
Ciurea, A.; Weber, U.; Stekhoven, D.
2015-01-01
in private practices in comparison to academic centers, adherence to ASAS treatment recommendations for TNF inhibition was equally high, and similar response rates to TNF blockers were achieved in both clinical settings. (First Release Nov 1 2014; J Rheumatol 2015; 42:101-5; doi 10.3899/jrheum.140229).......Objective. To evaluate the initiation of and response to tumor necrosis factor (TNF) inhibitors for axial spondyloarthritis (axSpA) in private rheumatology practices versus academic centers. The Journal of Rheumatology, Methods.We compared newly initiated TNF inhibition for axSpA in 363 patients...... was slightly higher in the hospital setting. Mean levels (+/- SD) of the Ankylosing Spondylitis Disease Activity Score were, however, virtually identical in private practices and academic centers (3.4 +/- 1.0 vs 3.4 +/- 0.9, p = 0.68). An Assessment of SpondyloArthritis international Society (ASAS40) response...
Brandhuber, A.; Gürdoğan, Ö.; Mooney, R.; Travaglini, G.; Yang, G.
2011-10-01
In this paper we continue our systematic study of form factors of half-BPS operators in mathcal{N} = 4 super Yang-Mills. In particular, we extend various on-shell techniques known for amplitudes to the case of form factors, including MHV rules, recursion relations, unitarity and dual MHV rules. As an application, we present the solution of the recursion relation for split-helicity form factors. We then consider form factors of the stress-tensor multiplet operator and of its chiral truncation, and write down supersymmetric Ward identities using chiral as well as non-chiral superspace formalisms. This allows us to obtain compact formulae for families of form factors, such as the maximally non-MHV case. Finally we generalise dual MHV rules in dual momentum space to form factors.
Maas, F. E.; Paschke, K. D.
2017-07-01
A broad program measuring parity-violation in electron-nuclear scattering has now provided a large set of precision data on the weak-neutral-current form-factors of the proton. Under comparison with well-measured electromagnetic nucleon form-factors, these measurements reveal the role of the strange quark sea on the low-energy interactions of the proton through the strange-quark-flavor vector form-factors. This review will describe the experimental program and the implications of the global data for the strange-quark vector form-factors. We present here a new fit to the world data.
On the Application of Correction Factor for Axial Power Distribution to CHF Correlation Development
International Nuclear Information System (INIS)
Kim, Kang Hoon; Kim, Hong Ju; Yang, Seung Geun; Park, Eung Jun; Hwang, Sun Tack; Chung, Sun Kyo
2005-01-01
The axial heat flux distribution in nuclear reactors is invariably non-uniform. Thus it is very important to validate the general applicability of CHF correlation developed with limited types of axial heat flux distribution to actual situation of various axial power shapes in reactor operation. Per the recent fuel development, CHF testing is performed for chopped cosine axial heat flux distribution only. Thus it is inevitable to re-clarify the validity of correction factor for non-uniform axial heat flux distribution to support the general applicability of CHF correlation developed with data recently tested. Two ways of approach are considered to care the effects of axial power distribution in CHF correlation development. With the first method, CHF correlation is developed based on the data of uniform axial heat flux distribution only. To apply the correlation to the data of various axially non-uniform heat flux distribution, a factor such as Tong's F-factor is applied to the predicted value by the correlation itself to correct the effects of upstream memory on CHF. With the second approach, CHF correlation is developed based on whole data with the concept of equivalent uniform heat flux for the data of non-uniform axial heat flux distribution. The equivalent uniform heat flux is a measured CHF value for the data of uniform axial heat flux distribution, but it is a pseudo-CHF with a corrective factor for the data of non-uniform axial heat flux distribution. The corrective factor is applied to predict CHF for any non-uniform axial heat flux distribution
The nucleon's strange form factors
International Nuclear Information System (INIS)
Pitt, Mark L.
2000-01-01
Knowledge of the nucleon's strange form factors will provide valuable insight into low energy hadron structure. Measurement of the vector strange form factor of the nucleon is accomplished through parity-violating electron scattering. This paper reviews the current status of this class of experiments
Heavy quark form factors at two loops in perturbative QCD
Energy Technology Data Exchange (ETDEWEB)
Ablinger, J.; Schneider, C. [Johannes Kepler Univ., Linz (Austria). Research Inst. for Symbolic Computation (RISC); Behring, A. [RWTH Aachen Univ. (Germany). Inst. fuer Theoretische Teilchenphysik und Kosmologie; Bluemlein, J.; Freitas, A. de; Marquard, P.; Rana, N. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Falcioni, G. [Nikhef, Amsterdam (Netherlands). Theory Group
2017-11-15
We present the results for heavy quark form factors at two-loop order in perturbative QCD for different currents, namely vector, axial-vector, scalar and pseudo-scalar currents, up to second order in the dimensional regularization parameter. We outline the necessary computational details, ultraviolet renormalization and corresponding universal infrared structure.
Peister, C.; George, R.; Omer, K.; Worswick, M. J.; Malcolm, S.; Dykeman, J.; Yau, C.; Soldaat, R.; Bernert, W.
2017-09-01
In this work, top-hat cross-section axial crush rail specimens with tailored properties along their length were investigated. These top-hat channels were hot stamped in a fully cooled die set from tailor-welded blanks (TWBs). The blanks were laser-welded and comprised Usibor® 1500-AS joined to Ductibor® 500-AS in 1.2 mm and 1.6 mm thicknesses. Micro-hardness measurements were taken along the length of the formed specimens to map the hardness profile along their length. The effect of gauge thickness on hardness was evaluated. The hardness profile of these TWB parts was compared to that of parts formed using tailored in-die heating (IDH).
Factorization of the Ising model form factors
International Nuclear Information System (INIS)
Assis, M; McCoy, B M; Maillard, J-M
2011-01-01
We present a general method for analytically factorizing the n-fold form factor integrals f (n) N,N (t) for the correlation functions of the Ising model on the diagonal in terms of the hypergeometric functions 2 F 1 ([1/2, N + 1/2]; [N + 1]; t) which appear in the form factor f (1) N,N (t). New quadratic recursion and quartic identities are obtained for the form factors for n = 2, 3. For n = 2, 3, 4 explicit results are given for the form factors. These factorizations are proved for all N for n = 2, 3. These results yield the emergence of palindromic polynomials canonically associated with elliptic curves. As a consequence, understanding the form factors amounts to describing and understanding an infinite set of palindromic polynomials, canonically associated with elliptic curves. From an analytical viewpoint the relation of these palindromic polynomials with hypergeometric functions associated with elliptic curves is made very explicitly, and from a differential algebra viewpoint this corresponds to the emergence of direct sums of differential operators homomorphic to symmetric powers of a second order operator associated with elliptic curve.
$K_{13}$ transition form factors
Chueng Ryong Ji
2001-01-01
The rainbow truncation of the quark Dyson-Schwinger equation is combined with the ladder Bethe-Salpeter equation for the meson bound state amplitudes and the dressed quark-W vertex in a manifestly covariant calculation of the K/sub l3/ transition form factors and decay width in the impulse approximation. With model gluon parameters previously fixed by the chiral condensate, the pion mass and decay constant, and the kaon mass, our results for the K/sub l3/ form factors and the kaon semileptonic decay width are in good agreement with the experimental data. (37 refs).
Effective Cross Section of Cold Formed Steel Column Under Axial Compression
Manikandan, P.; Pradeep, T.
2018-02-01
The compressive resistance of cold-formed steel (CFS) section may be governed by local, distortional or overall buckling and any apparent interaction between these modes. A new inventive stiffened CFS section is elected in this study, selected cross sections geometries and lengths are chosen such that all the types of buckling modes are met with. Buckling plot is plotted using linear elastic buckling analysis software (CUFSM). Using the test results obtained in the literature, the developed finite element model is calibrated and furthers a total of 126 parametric study is conducted such as a consequence of dimensions and the length of the cross section, thickness and yield stress. The FEA included relevant material and geometric imperfections. All the columns are analyzed under pin end conditions with axial compression. The analysis results demonstrate that the DSM equations generally assess the strength of stiffened section conservatively. Modifications to the DSM equations are recommended to evaluate the strength of stiffened section more precisely.
Strange mesonic transition form factor
International Nuclear Information System (INIS)
Goity, J.L.; Musolf, M.J.
1996-01-01
The strange-quark vector current ρ-to-π meson transition form factor is computed at one-loop order using strange meson intermediate states. A comparison is made with a φ-meson dominance model estimate. We find that one-loop contributions are comparable in magnitude to those predicted by φ-meson dominance. It is possible that the one-loop contribution can make the matrix element as large as those of the electromagnetic current mediating vector meson radiative decays. However, due to the quadratic dependence of the one-loop results on the hadronic form factor cutoff mass, a large uncertainty in the estimate of the loops is unavoidable. These results indicate that non-nucleonic strange quarks could contribute appreciable in moderate-parallel Q 2 parallel parity-violating electron-nucleus scattering measurements aimed at probing the strange-quark content of the nucleon. copyright 1996 The American Physical Society
Directory of Open Access Journals (Sweden)
Kohl Michael
2014-01-01
Full Text Available The elastic form factors of the nucleon characterize the distributions of charge and magnetization in momentum space and are important input for calculations of strong interaction phenomena and nuclear structure. The dramatic discrepancy in the observed ratio of elastic proton form factors between the Rosenbluth separation and polarization transfer methods has invoked numerous theoretical and experimental investigations. The previously neglected effect from two-photon exchange has become the favored explanation for the discrepancy. While the effect can not be calculated from first principles, it can be verified experimentally in several ways, most stringently by comparing the positron- proton and electron-proton elastic cross sections. The OLYMPUS experiment at DESY has been carried out to quantify the effect of two-photon exchange using intense stored positron and electron beams along with an internal unpolarized hydrogen target and a large acceptance detector to measure the ratio of the positron-proton and electron-proton elastic scattering cross sections. The status of proton form factor measurements and of the experimental efforts to verify the effect of two-photon exchange is presented, with some emphasis on the OLYMPUS experiment.
Bowley, John Francis; Kaye, Elizabeth Krall; Garcia, Raul Isidro
2017-08-01
The aim of this study was to determine the influence of long base lengths of a fixed partial denture (FPD) to rotational resistance with variation of vertical wall angulation. Trigonometric calculations were done to determine the maximum wall angle needed to resist rotational displacement of an experimental-FPD model in 2-dimensional plane. The maximum wall angle calculation determines the greatest taper that resists rotation. Two different axes of rotation were used to test this model with five vertical abutment heights of 3-, 3.5-, 4-, 4.5-, and 5-mm. The two rotational axes were located on the mesial-side of the anterior abutment and the distal-side of the posterior abutment. Rotation of the FPD around the anterior axis was counter-clockwise, Posterior-Anterior (P-A) and clockwise, Anterior-Posterior (A-P) around the distal axis in the sagittal plane. Low levels of vertical wall taper, ≤ 10-degrees, were needed to resist rotational displacement in all wall height categories; 2-to-6-degrees is generally considered ideal, with 7-to-10-degrees as favorable to the long axis of the abutment. Rotation around both axes demonstrated that two axial walls of the FPD resisted rotational displacement in each direction. In addition, uneven abutment height combinations required the lowest wall angulations to achieve resistance in this study. The vertical height and angulation of FPD abutments, two rotational axes, and the long base lengths all play a role in FPD resistance form.
International Nuclear Information System (INIS)
Radyushkin, A.V.
1980-01-01
The calculation of the next-to-leading order corrections to pion form factor Fsub(π)(Q) in the QCD shows that analysis of Fsub(π)(Q) is not a short-distance problem up to Q 2 =10 4 -10 6 GeV 2 . A QCD-inspired model is proposed which in a semi-phenomenological way, takes into account the most important confinement effects. The curve obtained for Fsub(π)(Q) is in good agreement with existing experimental data
DEFF Research Database (Denmark)
Fossen, T. I.; Blanke, Mogens
2000-01-01
Accurate propeller shaft speed controllers can be designed by using nonlinear control theory and feedback from the axial water velocity in the propeller disc. In this paper, an output feedback controller is derived, reconstructing the axial flow velocity from vehicle speed measurements, using...... a three-state model of propeller shaft speed, forward (surge) speed of the vehicle, and the axial flow velocity. Lyapunov stability theory is used to prove that a nonlinear observer combined with an output feedback integral controller provide exponential stability. The output feedback controller...... compensates for variations in thrust due to time variations in advance speed. This is a major problem when applying conventional vehicle-propeller control systems, The proposed controller is simulated for an underwater vehicle equipped with a single propeller. The simulations demonstrate that the axial water...
Separating form factor and nuclear model effects in quasielastic neutrino-nucleus scattering
Wieske, Joseph
2017-09-01
When studying neutrino oscillations an understanding of charged current quasielastic (CCQE) neutrino-nucleus scattering is imperative. This interaction depends on a nuclear model as well as knowledge of form factors. In the past, CCQE data from the MiniBooNE experiment was analyzed assuming the Relativistic Fermi Gas (RFG) nuclear model, an axial dipole form factor in, and using the the z-expansion for the axial form factor in. We present the first analysis that combines a non-RFG nuclear model, in particular the Correlated Fermi Gas nuclear model (CFG) of, and the z expansion for the axial form factor. This will allow us to separate form factor and nuclear model effects in CCQE scattering. This project was supported through the Wayne State University REU program under NSF Grant PHY-1460853 and by the DOE Grant DE-SC0007983.
Nerve growth factor regulates axial rotation during early stages of chick embryo development
Manca, Annalisa; Capsoni, Simona; Di Luzio, Anna; Vignone, Domenico; Malerba, Francesca; Paoletti, Francesca; Brandi, Rossella; Arisi, Ivan; Cattaneo, Antonino; Levi-Montalcini, Rita
2012-01-01
Nerve growth factor (NGF) was discovered because of its neurotrophic actions on sympathetic and sensory neurons in the developing chicken embryo. NGF was subsequently found to influence and regulate the function of many neuronal and non neuronal cells in adult organisms. Little is known, however, about the possible actions of NGF during early embryonic stages. However, mRNAs encoding for NGF and its receptors TrkA and p75NTR are expressed at very early stages of avian embryo development, before the nervous system is formed. The question, therefore, arises as to what might be the functions of NGF in early chicken embryo development, before its well-established actions on the developing sympathetic and sensory neurons. To investigate possible roles of NGF in the earliest stages of development, stage HH 11–12 chicken embryos were injected with an anti-NGF antibody (mAb αD11) that binds mature NGF with high affinity. Treatment with anti-NGF, but not with a control antibody, led to a dose-dependent inversion of the direction of axial rotation. This effect of altered rotation after anti NGF injection was associated with an increased cell death in somites. Concurrently, a microarray mRNA expression analysis revealed that NGF neutralization affects the expression of genes linked to the regulation of development or cell proliferation. These results reveal a role for NGF in early chicken embryo development and, in particular, in the regulation of somite survival and axial rotation, a crucial developmental process linked to left–right asymmetry specification. PMID:22308471
Nucleon form factors from high statistics mixed-action calculations with 2+1 flavors
Energy Technology Data Exchange (ETDEWEB)
Schroers, Wolfram; Edwards, Robert G; Engelhardt, Michael; Fleming, George Taminga; Hagler, Philipp; Lin, Huey-Wen; Lin, Mei-Feng; Meyer, Harvey B; Musch, Bernhard; Negele, John W; Orginos, Kostas; Pochinsky, Andrew V; Procura, Massimiliano; Renner, Dru B; Richards, David G; Syritsyn, Sergey N
2009-12-01
We present new high-statistics results for nucleon form factors at pion masses of approximately 290, 350, 500, and 600 MeV using a mixed action of domain wall valence quarks on an improved staggered sea. We perform chiral fits to both vector and axial form factors and compare our results to experiment.
Form factors in the projected linear chiral sigma model
International Nuclear Information System (INIS)
Alberto, P.; Coimbra Univ.; Bochum Univ.; Ruiz Arriola, E.; Fiolhais, M.; Urbano, J.N.; Coimbra Univ.; Goeke, K.; Gruemmer, F.; Bochum Univ.
1990-01-01
Several nucleon form factors are computed within the framework of the linear chiral soliton model. To this end variational means and projection techniques applied to generalized hedgehog quark-boson Fock states are used. In this procedure the Goldberger-Treiman relation and a virial theorem for the pion-nucleon form factor are well fulfilled demonstrating the consistency of the treatment. Both proton and neutron charge form factors are correctly reproduced, as well as the proton magnetic one. The shapes of the neutron magnetic and of the axial form factors are good but their absolute values at the origin are too large. The slopes of all the form factors at zero momentum transfer are in good agreement with the experimental data. The pion-nucleon form factor exhibits to great extent a monopole shape with a cut-off mass of Λ=690 MeV. Electromagnetic form factors for the vertex γNΔ and the nucleon spin distribution are also evaluated and discussed. (orig.)
A new multi-axial particle shape factor--application to particle sampling.
Dihalu, Dosti S; Geelhoed, Bastiaan
2011-09-21
Because for a given sample size the sampling uncertainty increases with increasing particle mass, the mass of a representative sample depends on the particle mass during chemical, physical and biological analysis. Sampling theory can be used to formulate the quantitative relationship between the particle mass and the corresponding mass or weight of a representative sample. But in practice, especially for small particles, it is often easier to evaluate the particle size in dimension of length (e.g. μm) rather than in dimension of mass (e.g. μg). In order to be able to apply sampling theory to predict the mass or weight of a representative sample, a well-defined methodology that relates the mass of a particle to its size is required. We here propose a new multi-axial shape factor which requires information of multiple sizes of the particle of interest, whereas a uniaxial shape factor only needs one. In view of the information loss that is implicit in the use of a one-dimensional shape factor like the Brunton shape factor, the here-proposed new multi-axial shape is expected to perform better. Experimental data confirm the better performance of the new shape factor. A multi-segment generalisation of the new multi-axial shape factor is proposed.
Electromagnetic N-N* transition form factors
International Nuclear Information System (INIS)
Devenish, R.C.E.; Eisenschitz, T.S.; Koerner, J.G.
1975-11-01
We define constraint-free electromagnetic N-N*(J) transition form factors for general abnormal and normal parity transitions and relate them to multipole and helicity transition form factors. Possible parametrizations of the constraint-free form factors are discussed, and various theoretically motivated simplifications are considered which are then compared to the available transition form factor data. If analysed in terms of the constraint-free form factors, a very simple picture is obtained for the three leading resonances P 33 , D 13 , and F 15 . (orig.) [de
International Nuclear Information System (INIS)
Gajewski, W.; Swiecki, M.
1975-01-01
This paper is devoted to the description of the present status of our knowledge about π meson elastic form factor. In the first section there is given a definition of the form factor on the basis of electromagnetic interactions, and its extension to weak and strong interactions. Next, there are reviewed theoretical models, which on the assumption of analyticity predict features of π meson form factor. In the last sections the results of experimental investigaton of π meson form factor are described with the stress on the results of the recent experiment made on Serpukhov accelerator in order to measure the π meson electromagnetic radius. (author)
Sieper, Joachim; Braun, Jürgen; Dougados, Maxime; Baeten, Dominique
2015-07-09
The term axial spondyloarthritis covers both non-radiographic disease and radiographic disease (also known as ankylosing spondylitis). Some studies have been performed to investigate the prevalence of axial spondyloarthritis, although most are limited to patients with radiographic disease. A strong genetic association has been shown between axial spondyloarthritis and human leukocyte antigen-B27 (HLA-B27), but the pathogenetic role of HLA-B27 has not yet been clarified. Tumour necrosis factor (TNF), IL-17, IL-23 and downstream pathways also seem to be important - based on the good results of therapies directed against these molecules - but their exact role in the inflammatory process is also not yet clear. Elucidating the interaction between osteoproliferation and inflammation will be crucial for the prevention of long-term structural damage of the bone. The development of new criteria for classification, diagnosis and screening of patients with axial spondyloarthritis will enable earlier intervention for this chronic inflammatory disease. MRI has become an important tool for the early detection of axial spondyloarthritis. NSAIDs and TNF blockers are effective therapies, including in the early non-radiographic stage. Therapeutic blockade of IL-17 or IL-23 seems to be a promising new treatment option. Tools for measuring quality of life in axial spondyloarthritis have become relevant to assess the impact that the disease has on patients. These diagnostic and therapeutic advances will continue to change the management of axial spondyloarthritis, and new insights into the disease pathogenesis will hopefully accelerate this process. For an illustrated summary of this Primer, visit: http://go.nature.com/51b1af.
Phenomenology of the deuteron electromagnetic form factors
International Nuclear Information System (INIS)
David Abbott; Abdellah Ahmidouch; H. Anklin; J. Arvieux; James P. Ball; Shelton Beedoe; Elizabeth Beise; Louis Bimbot; Werner Boeglin; Herbert Breuer; Roger Carlini; Nicholas Chant; Samuel Danagoulian; K. Dow; Jean-Eric Ducret; Jim Dunne; Lars Ewell; L. Eyraud; C. Furget; Michel Garcon; Ron Gilman; Charles Glashausser; Paul Gueye; Kenneth Gustafsson; Kawtar Hafidi; A. Honegger; J. Jourdan; Serge Kox; Gerfried Kumbartzki; L. Lu; Allison Lung; Pete Markowitz; Justin McIntyre; David Meekins; F. Merchez; Joseph Mitchell; R. Mohring; S. Mtingwa; H. Mrktchyan; D. Pitz; Liming Qin; Ronald Ransome; J.-S. R'eal; Philip Roos; Paul Rutt; Reyad Sawafta; Stepan Stepanyan; Raphael Tieulent; E. Tomasi-Gustafsson; William Turchinetz; K. Vansyoc; J. Volmer; E. Voutier; Claude Williamson; Stephen Wood; Chen Yan; Jianguo Zhao; W. Zhao
2000-01-01
A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data
Moltó, Anna; Paternotte, Simon; Claudepierre, Pascal; Breban, Maxime; Dougados, Maxime
2014-07-01
To estimate the frequency of use and effectiveness in daily practice of tumor necrosis factor α (TNFα) blockers in a population with inflammatory back pain suggestive of early axial spondyloarthritis (SpA). The Devenir des Spondylarthropathies Indifférenciées Récentes (DESIR) cohort is a prospective, multicenter, observational cohort of 708 patients with early (<3 years' duration) inflammatory back pain suggestive of axial SpA. The percentage of patients receiving TNFα blockers over the first 2 years of followup was estimated by survival analysis. To evaluate effectiveness, the primary outcome (40% improvement in disease activity according to the Assessment of SpondyloArthritis international Society criteria [ASAS40]) was compared in patients who received TNFα blockers versus control patients who received any other treatment (usual care). Controls were matched to the patients based on a propensity score method. A total of 30.2% (95% confidence interval [95% CI] 26.7-33.7) patients received at least 1 TNFα blocker during the 24 months of followup. The percentage of ASAS40 responders was 31.5% (62 of 197 patients) in the group receiving TNFα blockers versus 13.2% (26 of 197) in the control group (OR 2.99 [95% CI 1.80-4.99], P = 0.0002). This effectiveness was more pronounced in the subgroup of patients with sacroiliitis identified on magnetic resonance imaging, with 46% of ASAS40 responders receiving TNFα blockers versus 15% of ASAS40 responders receiving usual care (OR 4.99 [95% CI 2.17-11.51]). Our study shows that TNFα blockers are frequently used in daily practice to treat patients with early axial SpA. Our findings confirm the effectiveness of TNFα blockers as compared to any other treatment, especially in the subgroup of patients with sacroiliitis on MRI. Copyright © 2014 by the American College of Rheumatology.
Small Form Factor RFID Applicator, Phase I
National Aeronautics and Space Administration — The proposed development of a small form factor Astrobee dedicated RFID label applicator will allow current and future free flying vehicles to place RFID labels...
Make Projects Small Form Factor PCs
Wessels, Duane
2006-01-01
Shoebox sized and smaller, small-form-factor PCs can pack as much computing muscle as a full-sized desktop computer. They consumer less power, have few or no moving parts, and are very quiet. Whether you plan to use one as a standalone PC or want to embed it in your next hacking project, a small-form-factor PC can be a lot of fun to build. Make Projects: Small Form Factor PCs is the only book available that shows you how to build small-form-factor PCs -- from kits and from scratch -- that are more interesting and more personalized than what a full-sized PC can give you. Included in the book
Resistance of full veneer metal crowns with different forms of axial grooves
Hidayat, A. S.; Masulili, C.; Indrasari, M.
2017-08-01
Dental crowns or bridges can occasionally come loose or separate from the tooth during chewing, particularly when they are situated on small, short, and conical teeth. The main cause of this separation is a lack of retention and resistance to the tooth. There are several methods available to increase the retention and resistance of the crown during both inlay and onlay preparation, including parallelism, groove preparation, crown build-up, and surface roughness. The aim of this study was to determine the differences in resistance of full veneer metal crowns with various forms of groove preparation. The study involved the compressive strength testing of a total of 24 specimens, namely six specimens without groove preparation, six specimens with box-shaped grooves, six specimens with V-shaped grooves, and six specimens with half round grooves. The mean values of the metal crowns that separated from the teeth during testing were 27.97 ± 1.08 kgF for the crowns with box-shaped grooves, 6.15 ± 0.22 kgF for those with V-shaped grooves, 1.77 ± 0.12 kgF for those with half round grooves, and 0.95 ± 0.13 kgF for those without grooves. This study found that the resistance is best in crowns with box-shaped grooves, followed by those with V-shaped grooves, half round grooves, and those without groove. When clinicians are working on short and conical molar teeth, it is therefore recommended that box-shaped grooves are used to increase the resistance of the crown.
Machado, Christiano Bittencourt; de Albuquerque Pereira, Wagner Coelho; Talmant, Maryline; Padilla, Frédéric; Laugier, Pascal
2010-08-01
This work aimed at computationally evaluating the compositional factors in fracture healing affecting ultrasound axial transmission (UAT), using four numerical daily-changing healing models, representing more realistic clinical conditions. Using two-dimensional (2-D) simulations, a 1-MHz source and a receiver were positioned parallel to the bone surface to detect the first arriving signal (FAS). The time-of-flight of the FAS (TOF(FAS)) was found to be sensitive only to superficial modifications in the propagation path. It was also shown that callus mature bone better explained alone the variation in TOF(FAS) (R(2) >or= 0.70, p consolidation delays and nonunions. Copyright 2010 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
Blachier, Martin; Canouï-Poitrine, Florence; Dougados, Maxime; Lethuaut, Aurélie; Fautrel, Bruno; Ferkal, Salah; Le Corvoisier, Philippe; Farrenq, Valérie; Poulain, Cécile; Ghaleh, Bijan; Bastuji-Garin, Sylvie; Claudepierre, Pascal
2013-09-01
To assess whether factors such as inflammation by laboratory tests and MRI differ between early axial SpA with and without radiographic lesions. Cross-sectional analysis of baseline data from Devenir des Spondylarthropathies Indifferenciées Récentes (DESIR) cohort patients having recent-onset inflammatory back pain and meeting Assessment of SpondyloArthritis international Society criteria. The baseline evaluation included radiographs and MRI of the SI joints (SIJs) and spine. Patients were classified as having radiographic lesions if they had at least one obvious sacroiliitis, grade 2 for at least one vertebral corner or grade 1 for at least two vertebral corners (at the cervical or lumbar level, according to the modified Stoke Ankylosing Spondylitis Spine Score). Associations between baseline characteristics and the presence of radiographic lesions were evaluated by estimating multi-adjusted odd ratios (aORs) and their 95% CIs using a logistic regression model. Of 475 patients, 180 (37.9%) had radiographic lesions. Factors positively associated with radiographic lesions were alcohol use (aOR 2.42; 95% CI 1.31, 4.44; P = 0.005), CRP level (aOR 1.44; 95% CI 1.13, 1.84; P = 0.003) and SIJ inflammation by MRI (aOR 2.25; 95% CI 1.40, 3.60; P = 0.001); negative associations occurred with good NSAID responsiveness (aOR 0.44; 95% CI 0.24, 0.81; P = 0.008); spinal MRI inflammation was associated with radiographic lesions only in smokers (aOR 1.99; 95% CI 1.01, 3.92; P = 0.048). Alcohol use, poor responsiveness to NSAIDs, CRP elevation, SIJ MRI inflammation and spinal MRI inflammation in smokers were independently associated with radiographic lesions in early axial SpA.
Magnetic form factors of the trinucleons
Energy Technology Data Exchange (ETDEWEB)
Schiavilla, R; Pandharipande, V R; Riska, Dan-Olof
1989-11-01
The magnetic form factors of ^{3}H and ^{3}He are calculated with the Monte Carlo method from variational ground-state wave functions obtained for the Argonne and Urbana two- and three-nucleon interactions. The electromagnetic current operator contains one- and two-body terms that are constructed so as to satisfy the continuity equation with the two-nucleon potential in the Hamiltonian. The results obtained with the Argonne two-nucleon interaction are in overall agreement with the empirical values. It appears that the remaining theoretical uncertainty, in the calculation of these form factors from a given interaction model, is dominated by that in the electromagnetic form factors of the nucleon. It is found that the isovector magnetic form factors are rather sensitive to the details of the isospin-dependent tensor force, and they are much better reproduced with the Argonne than the Urbana potential. The isoscalar magnetic form factors appear to be sensitive to the spin-orbit interactions, and are better reproduced with the Urbana potential. The Argonne potential has a stronger τ1∙τ2 tensor force, while the Urbana one has a shorter-range spin-orbit interaction.
Study on the capacity of cold-formes steel built-up battened colums under axial compression
Directory of Open Access Journals (Sweden)
Dr. M. Anbarasu
Full Text Available This paper presents the theoretical and numerical investigation results of the pin ended cold-formed steel built-up battened columns under axial compression. The finite element model was developed using the finite element software ABAQUS. The comparison of finite element analysis results match with the test results available in the literature shows that the analysis model can simulate the buckling behaviour and ultimate capacity of cold-formed steel built-up columns. Three types of sections were selected based on the limitations provided in AISI S100-2007 for prequalified sections for single lipped channel. Spacing between the chords is chosen such that the moment of inertia about major axis equals the moment of inertia about minor axis. After the verification of the finite element model, parametric study has been carried out by varying the slenderness ratio and number of battens. Two types of analytical models were used to obtain the ultimate load by the direct strength method. The ultimate loads from FEA and DSM were compared. At the end, a design recommendation is proposed for DSM to evaluate ultimate strength of the lipped channel built-up battened columns.
Color-kinematic duality for form factors
International Nuclear Information System (INIS)
Boels, Rutger H.; Kniehl, Bernd A.; Tarasov, Oleg V.; Yang, Gang
2012-12-01
Recently a powerful duality between color and kinematics has been proposed for integrands of scattering amplitudes in quite general gauge theories. In this paper the duality proposal is extended to the more general class of gauge theory observables formed by form factors. After a discussion of the general setup the existence of the duality is verified in two and three loop examples in four dimensional maximally supersymmetric Yang-Mills theory which involve the stress energy tensor multiplet. In these cases the duality reproduces known results in a particularly transparent and uniform way. As a non-trivial application we obtain a very simple form of the integrand of the four-loop two-point (Sudakov) form factor which passes a large set of unitarity cut checks.
Color-kinematic duality for form factors
Energy Technology Data Exchange (ETDEWEB)
Boels, Rutger H.; Kniehl, Bernd A.; Tarasov, Oleg V.; Yang, Gang [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik
2012-12-15
Recently a powerful duality between color and kinematics has been proposed for integrands of scattering amplitudes in quite general gauge theories. In this paper the duality proposal is extended to the more general class of gauge theory observables formed by form factors. After a discussion of the general setup the existence of the duality is verified in two and three loop examples in four dimensional maximally supersymmetric Yang-Mills theory which involve the stress energy tensor multiplet. In these cases the duality reproduces known results in a particularly transparent and uniform way. As a non-trivial application we obtain a very simple form of the integrand of the four-loop two-point (Sudakov) form factor which passes a large set of unitarity cut checks.
The Form Factors of the Nucleons
Energy Technology Data Exchange (ETDEWEB)
Perdrisat, Charles F. [William and Mary College, JLAB
2013-11-01
There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has been greatly improved by performing double-polarization experiments, in comparison with with pre-vious unpolarized cross section data. Here we will review the experimental data base in view of the new results for the proton and the neutron, obtained at MIT-Bates, JLab and MAMI. The rapid evolution of phenomenological models triggered by these high- precision experiments will be discussed. In particular, the possibility that the proton is non-spherical in its ground state, and that the transverse charge density are model in- dependently defined in the infinite momentum frame. Likewise, flavor decomposition of the nucleon form factors into dressed u and d quark form factors, may give information about the quark-diquark structure of the nucleon. The current proton radius "crisis" will also be discussed.
Charm form factors in hadronic interactions
International Nuclear Information System (INIS)
Bracco, M. E.; Navarra, F. S.; Nielsen, M.; Chiapparini, M.
2010-01-01
We calculate the form factors and the coupling constants in vertices with charm mesons, such as ρD*D*, in the framework of QCD sum rules. We first discuss the applications of these form factors in heavy ion collisions and in B decays. We then present an introduction to the method of QCD sum rules and describe how to work with the three-point function. We give special attention to the procedure employed to extrapolate results obtained in the deep euclidean region to the poles of the particles, located in the time-like region. Finally we present a table of ready-to-use parametrizations of all the form factors, which are relevant for the processes mentioned in the introduction. We also give the coupling constants.
Nucleon form factors in the nuclear medium
Park, Chanyong; Lee, Jung Hun
2018-01-01
By using the AdS/CFT correspondence, we investigate various form factors between nucleons and mesons in a nuclear medium. In order to describe a nuclear medium holographically, we take into account the thermal charged AdS geometry with an appropriate IR cutoff. After introducing an anomalous dimension as a free parameter, we investigate how the nucleon’s mass is affected by the change of the anomalous dimension. Moreover, we study how the form factors of nucleons rely on the properties of the nuclear medium. We show that in a nuclear medium with different numbers of proton and neutron, the degenerated nucleon form factor in the vacuum is split into four different values depending on the isospin charges of nucleon and meson.
Paramagnetic form factors from itinerant electron theory
International Nuclear Information System (INIS)
Cooke, J.F.; Liu, S.H.; Liu, A.J.
1985-01-01
Elastic neutron scattering experiments performed over the past two decades have provided accurate information about the magnetic form factors of paramagnetic transition metals. These measurements have traditionally been analyzed in terms of an atomic-like theory. There are, however, some cases where this procedure does not work, and there remains the overall conceptual problem of using an atomistic theory for systems where the unpaired-spin electrons are itinerant. We have recently developed computer codes for efficiently evaluating the induced magnetic form factors of fcc and bcc itinerant electron paramagnets. Results for the orbital and spin contributions have been obtained for Cr, Nb, V, Mo, Pd, and Rh based on local density bands. By using calculated spin enhancement parameters, we find reasonable agreement between theory and neutron form factor data. In addition, these zero parameter calculations yield predictions for the bulk susceptibility on an absolute scale which are in reasonable agreement with experiment in all treated cases except palladium
Electromagnetic proton form factors: perspectives for PANDA
Directory of Open Access Journals (Sweden)
Tomasi-Gustafsson Egle
2014-03-01
Full Text Available The PANDA collaboration studies fundamental aspects of the strong interaction in the transition region between non-perturbative and perturbative QCD, investigating charmonium spectroscopy, hybrids and glueballs, hypernuclei, light and heavy meson production with antiproton beams. In this contribution we focus on leptonic final channels which give access to nucleon electromagnetic form factors. The expected precision on the electric and magnetic form factors of the proton in the time-like region and the radiative corrections to be applied to the data are discussed.
Weak form factors of beauty baryons
International Nuclear Information System (INIS)
Ivanov, M.A.; Lyubovitskij, V.E.
1992-01-01
Full analysis of semileptonic decays of beauty baryons with J p =1/2 2 and J p =3/2 2 into charmed ones within the Quark Confinement Model is reported. Weak form factors and decay rates are calculated. Also the heavy quark limit m Q →∞ (Isgur-Wise symmetry) is examined. The weak heavy-baryon form factors in the Isgur-Wise limit and 1/m Q -corrections to them are computered. The Ademollo-Gatto theorem is spin-flavour symmetry of heavy quarks is checked. 33 refs.; 1 fig.; 9 tabs
$K_{l3}$ transition form factors
Ji, C R; Ji, Chueng-Ryong; Maris, Pieter
2001-01-01
The rainbow truncation of the quark Dyson-Schwinger equation is combined with the ladder Bethe-Salpeter equation for the meson bound state amplitudes and the dressed quark-W vertex in a manifestly covariant calculation of the K_{l3} transition form factors and decay width in impulse approximation. With model gluon parameters previously fixed by the chiral condensate, the pion mass and decay constant, and the kaon mass, our results for the K_{l3} form factors and the kaon semileptonic decay width are in good agreement with the experimental data.
Simple parametrization of nucleon form factors
International Nuclear Information System (INIS)
Kelly, J.J.
2004-01-01
This Brief Report provides simple parametrizations of the nucleon electromagnetic form factors using functions of Q 2 that are consistent with dimensional scaling at high Q 2 . Good fits require only four parameters each for G Ep , G Mp , and G Mn and only two for G En
Chiral analysis of baryon form factors
Energy Technology Data Exchange (ETDEWEB)
Gail, T.A.
2007-11-08
This work presents an extensive theoretical investigation of the structure of the nucleon within the standard model of elementary particle physics. In particular, the long range contributions to a number of various form factors parametrizing the interactions of the nucleon with an electromagnetic probe are calculated. The theoretical framework for those calculations is chiral perturbation theory, the exact low energy limit of Quantum Chromo Dynamics, which describes such long range contributions in terms of a pion-cloud. In this theory, a nonrelativistic leading one loop order calculation of the form factors parametrizing the vector transition of a nucleon to its lowest lying resonance, the {delta}, a covariant calculation of the isovector and isoscalar vector form factors of the nucleon at next to leading one loop order and a covariant calculation of the isoscalar and isovector generalized vector form factors of the nucleon at leading one loop order are performed. In order to perform consistent loop calculations in the covariant formulation of chiral perturbation theory an appropriate renormalization scheme is defined in this work. All theoretical predictions are compared to phenomenology and results from lattice QCD simulations. These comparisons allow for a determination of the low energy constants of the theory. Furthermore, the possibility of chiral extrapolation, i.e. the extrapolation of lattice data from simulations at large pion masses down to the small physical pion mass is studied in detail. Statistical as well as systematic uncertainties are estimated for all results throughout this work. (orig.)
Nucleon and Deuteron Form Factors from BLAST
International Nuclear Information System (INIS)
Hasell, D. K.
2009-01-01
The BLAST experiment was designed to study in a systematic manner the spin-dependent, electromagnetic interaction on hydrogen and deuterium. Measuring only asymmetries in electron scattering with respect to the beam helicity, target spin, or both; the BLAST experiment was able to extract information on nucleon and deuteron form factors independent of beam intensity or target density. By further forming 'super-ratios' of asymmetries, measurements were possible independent of beam and target polarization thus reducing uncertainties due to these quantities as well. Some of the form factor results from BLAST will be briefly presented here. Also, in response to observed discrepancies between polarization measurements and those obtained using traditional Rosenbluth separation techniques a proposed experiment, OLYMPUS, which will use the BLAST detector to measure the two photon contribution to elastic electron scattering will also be presented.
Baryon electromagnetic form factors at BESIII
Directory of Open Access Journals (Sweden)
Dbeyssi Alaa
2017-01-01
Full Text Available Electromagnetic form factors are fundamental quantities which parameterize the electric and magnetic structure of hadrons. This contribution reports on the measurements of baryon electromagnetic form factors at the BESIII experiment in Beijing. The Beijing e+e− collider BEPCII is a double-ring symmetric collider running at √s between 2.0 and 4.6 GeV. Baryon electromagnetic form factors can be measured at BESIII in direct e+e−-annihilation and in initial state radiation processes. Based on the data collected by the BESIII detector at 12 center of mass energies between 2.23 and 3.67 GeV, the e+e− → p̄p cross section and the time-like proton form factor is measured. Preliminary results from the analysis of the initial state radiation process e+e− → p̄pγ using a data set of 7.408 fb−1 collected at center-of-mass energies between 3.773 and 4.6 GeV, are also presented. The cross section for e+e−→Λ¯Λ${e^ + }{e^ - } \\to \\bar \\Lambda \\Lambda $ is measured based on 40.5 pb−1 data collected at 4 energy points from the threshold up to 3.08 GeV. Preliminary results on the total cross section and the Λ effective form factor are shown. Ongoing analysis based on the high luminosity energy scan from 2015 and from radiative return at different √s are also described.
Abou-Haïdar, Z.; Bocci, A.; Alvarez, M. A. G.; Espino, J. M.; Gallardo, M. I.; Cortés-Giraldo, M. A.; Ovejero, M. C.; Quesada, J. M.; Arráns, R.; Prieto, M. Ruiz; Vega-Leal, A. Pérez; Nieto, F. J. Pérez
2012-04-01
In this work we present the output factor measurements of a clinical linear accelerator using a silicon strip detector coupled to a new system for complex radiation therapy treatment verification. The objective of these measurements is to validate the system we built for treatment verification. The measurements were performed at the Virgin Macarena University Hospital in Seville. Irradiations were carried out with a Siemens ONCOR™ linac used to deliver radiotherapy treatment for cancer patients. The linac was operating in 6 MV photon mode; the different sizes of the fields were defined with the collimation system provided within the accelerator head. The output factor was measured with the silicon strip detector in two different layouts using two phantoms. In the first, the active area of the detector was placed perpendicular to the beam axis. In the second, the innovation consisted of a cylindrical phantom where the detector was placed in an axial plane with respect to the beam. The measured data were compared with data given by a commercial treatment planning system. Results were shown to be in a very good agreement between the compared set of data.
Strange Nucleon Form Factors from ep and vp Elastic Scattering
Energy Technology Data Exchange (ETDEWEB)
Pate, S.F. [Physics Department, New Mexico State University, Las Cruces NM 88003 (United States)]. e-mail: pate@nmsu.edu
2007-12-15
The recent parity-violating ep forward-scattering elastic asymmetry data from Jefferson Lab (HAPPEx and G0), when combined with the vp elastic cross section data from Brookhaven (E734), permit an extraction of the strangeness contribution to the vector and axial nucleon form factors for momentum transfers in the range 0.45 < Q{sup 2} < 1.0 GeV{sup 2}. These results, combined with the recent determination of the strange vector form factors at Q{sup 2} = 0.1 GeV{sup 2} (SAMPLE, HAPPEx, PVA4, G0) have been interpreted in terms of uudss{sup -} configurations very different from the kaon-loop configurations usually associated with strangeness in the nucleon. New experiments are being proposed to improve the state of our knowledge of the vp elastic cross section -- these new experiments will push the range of Q{sup 2} to much lower values, and greatly increase the precision of the vp elastic data. One outcome of this can be a measurement of the strangeness contribution to the nucleon spin, {delta}s. Nuclear targets (e.g. C or Ar) are to be used in these neutrino experiments, and so a deep understanding of the nuclear physics, particularly in regard to final state effects, is needed before the potential of these precision experiments can be fully realized. (Author)
Elastic magnetic form factors of exotic nuclei
International Nuclear Information System (INIS)
Dong Tiekuang; Guo Yanqing; Ren Zhongzhou
2007-01-01
How to identify the orbital of the valence nucleon(s) of exotic nuclei is an important problem. The elastic magnetic electron scattering is an excellent probe to determine the valence structure of odd-A nuclei. The relativistic mean-field theory has been successfully applied to systematic studies of the elastic charge electron scattering from even-even exotic nuclei. The extension of this method to investigate the elastic magnetic electron scattering from odd-A exotic nuclei is a natural generalization. The experimental form factors of 17 O and 41 Ca are reproduced very well with the help of the spectroscopic factors which are introduced into the relativistic treatment of the magnetic electron scattering for the first time. The emphases are put on the magnetic form factors of 15,17,19 C, 23 O, 17 F, and 49,59 Ca calculated in the relativistic impulse approximation. Great differences have been found in the form factors of the same nucleus with different configurations. Therefore, the elastic magnetic electron scattering can be used to determine the orbital of the last nucleon of odd-A exotic nuclei. Our results can provide references for the electron scattering from exotic nuclei in the near future
International Nuclear Information System (INIS)
Suwardi, S.
2001-01-01
The presented paper is a preliminary step to evaluate the effect of radial and axial distribution of power generation on thermal analysis of whole fuel pin model with large L/D ratio. The model takes into account both radial and axial distribution of power generation due to power depression and core geometry, temperature and microstructure dependent on thermal conductivity. The microstructure distribution and the gap conductance for typical steady-state situation are given for the sensitivity analysis. The temperature and thermal conductivity distribution along the radial and axial directions obtained by different power distribution is used to indicate the sensitivity of power depression and power factor on thermal aspect. The evaluation is made for one step of incremental time and steady state approach is used. The analysis has been performed using a finite element-finite difference model. The result for typical reactor fuel shows that the sensitivity is too important to be omitted in thermal model
Form factors of heavy mesons in QCD
International Nuclear Information System (INIS)
Shifman, M.A.; Vysotsky, M.I.
1980-01-01
Logarithmic corrections to form factors of mesons built from heavy quarks are dirived in the framework of quantum chromodynamics. The reactions e + e - → etasub(c)γ and H → J/PSIγ are considered as an example. A novel feature as compared to the well studied problem of the pion form factor is the existence of the transformations between the quark-antiquark state c anti c and the gluonic one. O(αsub(s)) corrections are calculated exactly. An infinite series of the leading logarithmic terms is summed up with the help of the operator technique. Apart from already known results for quark operators some new results referring to gluon operators and their mixing with the quark ones are used. Two alternative derivations of the multiplicatively renormalizable operators are given. The first one reduces to a direct computation of the mixing matrix and its diagonalization, the second derivation is based on conformal symmetry considerations
Nucleon form factors. Probing the chiral limit
International Nuclear Information System (INIS)
Goeckeler, M.; Haegler, P.; Horsley, R.
2006-10-01
The electromagnetic form factors provide important hints for the internal structure of the nucleon and continue to be of major interest for experimentalists. For an intermediate range of momentum transfers the form factors can be calculated on the lattice. However, reliability of the results is limited by systematic errors due to the required extrapolation to physical quark masses. Chiral effective field theories predict a rather strong quark mass dependence in a range which was yet unaccessible for lattice simulations. We give an update on recent results from the QCDSF collaboration using gauge configurations with Nf=2, non-perturbatively O(a)-improved Wilson fermions at very small quark masses down to 340 MeV pion mass, where we start to probe the relevant quark mass region. (orig.)
Elastic form factors at higher CEBAF energies
Energy Technology Data Exchange (ETDEWEB)
Petratos, G.G. [Kent State Univ., OH (United States)
1994-04-01
The prospects for elastic scattering from few body systems with higher beam energies at CEBAF is presented. The deuteron and{sup 3}He elastic structure functions A(Q{sup 2}) can be measured at sufficiently high momentum transfers to study the transition between the conventional meson-nucleon and the constituent quark-gluon descriptions. Possible improvements in the proton magnetic form factor data are also presented.
Thermal stress intensity factor for an axial crack in a clad cylinder
International Nuclear Information System (INIS)
Kuo, An Yu; Deardorf, A.F.; Riccardella, P.C.
1993-01-01
Many clad pressure vessels have been found to have cracks running through the inside surface cladding and into the base material. Although Young's moduli and Poisson's ratios of the clad and base materials are about the same for most of the industrial applications, coefficients of thermal expansion of the two dissimilar materials, clad and base materials, are usually quite different. For example, low alloy ferritic steel is a common base material for reactor pressure vessels (RPV) and the vessels are usually clad with austenitic stainless steel. Young's moduli for the low alloy steel and stainless steel at 350 F are 29,000 ksi and 28,000 ksi, respectively, while their coefficients of thermal expansion are 7.47x10 -6 in/in and 9.50x10 -6 in/in-degree F, respectively. The mismatch in coefficients of thermal expansion will cause high residual thermal stress even when the entire vessel is at a uniform temperature. This residual stress is one of the primary reasons why so many cracks have been found in the cladded components. In performing reactor pressure vessel integrity evaluation, such as computing probability of brittle fracture of the RPV, it is necessary to calculate stress intensity factors for cracks, which initiate from the clad material and run into the base metal. This paper presents a convenient method of calculating stress intensity factor for an axial crack emanating from the inside surface of a cladded cylinder under thermal loading. A J-integral like line integral was derived and used to calculate the stress intensity factors from finite element stress solutions of the problem
Flavor content of nucleon form factors
Energy Technology Data Exchange (ETDEWEB)
Bijker, R. [Departamento de Estructura de la Materia, lnstituto de Ciencias Nucleares, UNAM, AP 70-543, 04510 Mexico D.F. (Mexico); Santopinto, E [l.N.F.N. and Dipartimento di Fisica, via Dodecaneso 33, Genova, I-16146 (Italy)]. e-mail: bijkernucleares. unam. mx
2007-12-15
The flavor content of nucleon form factors is analyzed using two different theoretical approaches. The first is based on a phenomenological two-component model in which the external photon couples to both an intrinsic three-quark structure and a meson cloud via vector-meson dominance. The flavor content of the nucleon form factors is extracted without introducing any additional parameter. A comparison with recent data from parity-violating electron scattering experiments shows a good overall agreement for the strange form factors. A more microscopic approach is that of an unquenched quark model proposed by Geiger and Isgur which is based on valence quark plus glue dominance to which quark-antiquark pairs are added in perturbation. In the original version the importance of ss loops in the proton was studied. Here we present the formalism for a new generation of unquenched quark models which, among other extensions, includes the contributions of uu and dd loops. Finally, we discuss some preliminary results in the closure limit. (Author)
Higgs form factors in Associated Production
Isidori, Gino; CERN
2014-01-01
We further develop a form factor formalism characterizing anomalous interactions of the Higgs-like boson (h) to massive electroweak vector bosons (V) and generic bilinear fermion states (F). Employing this approach, we examine the sensitivity of pp -> F ->Vh associated production to physics beyond the Standard Model, and compare it to the corresponding sensitivity of h -> V F decays. We discuss how determining the Vh invariant-mass distribution in associated production at LHC is a key ingredient for model-independent determinations of h V F interactions. We also provide a general discussion about the power counting of the form factor's momentum dependence in a generic effective field theory approach, analyzing in particular how effective theories based on a linear and non-linear realization of the SU(2)_L x U(1)_Y gauge symmetry map into the form factor formalism. We point out how measurements of the differential spectra characterizing h -> V F decays and pp -> F -> Vh associated production could be the leadi...
Kiguchi, Misaki M.; Hager, Eric S.; Winger, Daniel G.; Hirsch, Stanley A.; Chaer, Rabih A.; Dillavou, Ellen D.
2014-01-01
OBJECTIVES Refluxing perforators contribute to venous ulceration. We sought to describe patient characteristics and procedural factors that (1) impact rates of incompetent perforator vein (IPV) thrombosis with ultrasound-guided sclerotherapy (UGS) and (2) impact the healing of venous ulcers (CEAP 6) without axial reflux. METHODS Retrospective review of UGS of IPV injections from 1/2010–11/2012 identified 73 treated venous ulcers in 62 patients. Patients had no other superficial/axial reflux and were treated with standard wound care and compression. Ultrasound was used to screen for refluxing perforators near ulcer(s), and these were injected with sodium tetradecyl sulfate or polidocanol foam and assessed for thrombosis at 2 weeks. Demographic data, comorbidities, treatment details and outcomes were analyzed. Univariate and multivariable modeling was performed to determine covariates predicting IPV thrombosis and ulcer healing. RESULTS 62 patients with active ulcers for an average of 28 months with compression therapy prior to perforator treatment had an average age of 57.1 years, were 55% male, 36% had a history of DVT and 30% had deep venous reflux. 32 patients (52%) healed ulcers, while 30 patients (48%) had non-healed ulcer(s) in mean follow-up of 30.2 months. Ulcers were treated with 189 injections, with average thrombosis rate of 54%. Of 73 ulcers, 43 ulcers healed (59%), and 30 ulcers did not heal (41%). Patients that healed ulcers had an IPV thrombosis rate of 69 % vs. 38% in patients who did not heal (Pulcer healing found complete IPV thrombosis was a positive predictor (P=.02), while large initial ulcer area was a negative predictor (P=.08). Increased age was associated with fewer ulcer recurrences (P=.05). Hypertension and increased follow-up time predicted increased ulcer recurrences (P=.04, P=.02). Calf vein thrombosis occurred after 3% (6/189) of injections. CONCLUSIONS Thrombosis of IPVs with UGS increases venous ulcer healing in a difficult patient
Strange form factors of the proton: a new analysis of the ν (antiν) data of the BNL-734 experiment
International Nuclear Information System (INIS)
Alberico, W.M.; Barbaro, M.B.; Bilenky, S.M.; Caballero, J.A.; Giunti, C.; Maieron, C.; Moya Guerra, E. de; Udias, J.M.
1999-01-01
We consider ratios of elastic ν(antiν)-proton cross sections measured by the Brookhaven BNL-734 experiment and use them to obtain the neutral current (NC) over charged current (CC) neutrino-antineutrino asymmetry. We discuss the sensitivity of these ratios and of the asymmetry to the electric, magnetic and axial strange form factors of the nucleon and to the axial cutoff mass M A . We show that the effects of the nuclear structure and interactions on the asymmetry and, in general, on ratios of cross sections are negligible. We find some restrictions on the possible values of the parameters characterizing the strange form factors. We show that a precise measurement of the neutrino-antineutrino asymmetry would allow the extraction of the axial and vector magnetic strange form factors in a model independent way. The neutrino-antineutrino asymmetry turns out to be almost independent on the electric strange form factor and on the axial cutoff mass
Nucleon form factors from 5D skyrmions
Energy Technology Data Exchange (ETDEWEB)
Panico, Giuliano [Bethe Center for Theoretical Physics and Physikalisches Institut der Universitaet Bonn, Nussallee 12, 53115 Bonn (Germany); Wulzer, Andrea [Institut de Theorie des Phenomenes Physiques, EPFL, CH-1015 Lausanne (Switzerland)], E-mail: andrea.wulzer@epfl.ch
2009-06-15
Several aspects of hadron physics are well described by a simple 5D effective field theory. Baryons arise in this scenario as 'large' (and therefore calculable) 5D skyrmions. We extend and refine the existing analysis of this 5D soliton, which is fairly non-trivial due to the need of numerical methods. We perform the complete quantization of those collective coordinates which are relevant for computing the static observables like the nucleon form factors. We compare the result with simple expectations about large-N{sub c} QCD and with the experimental data. An agreement within 30% is found.
Neutron electric form factor via recoil polarimetry
International Nuclear Information System (INIS)
Richard Madey; Andrei Semenov; Simon Taylor; Aram Aghalaryan; Erick Crouse; Glen MacLachlan; Bradley Plaster; Shigeyuki Tajima; William Tireman; Chenyu Yan; Abdellah Ahmidouch; Brian Anderson; Razmik Asaturyan; O. Baker; Alan Baldwin; Herbert Breuer; Roger Carlini; Michael Christy; Steve Churchwell; Leon Cole; Samuel Danagoulian; Donal Day; Mostafa Elaasar; Rolf Ent; Manouchehr Farkhondeh; Howard Fenker; John Finn; Liping Gan; Kenneth Garrow; Paul Gueye; Calvin Howell; Bitao Hu; Mark Jones; James Kelly; Cynthia Keppel; Mahbubul Khandaker; Wooyoung Kim; Stanley Kowalski; Allison Lung; David Mack; D. Manley; Pete Markowitz; Joseph Mitchell; Hamlet Mkrtchyan; Allena Opper; Charles Perdrisat; Vina Punjabi; Brian Raue; Tilmann Reichelt; Joerg Reinhold; Julie Roche; Yoshinori Sato; Wonick Seo; Neven Simicevic; Gregory Smith; Samuel Stepanyan; Vardan Tadevosyan; Liguang Tang; Paul Ulmer; William Vulcan; John Watson; Steven Wells; Frank Wesselmann; Stephen Wood; Chen Yan; Seunghoon Yang; Lulin Yuan; Wei-Ming Zhang; Hong Guo Zhu; Xiaofeng Zhu
2003-01-01
The ratio of the electric to the magnetic form factor of the neutron, G En /G Mn , was measured via recoil polarimetry from the quasielastic d((pol-e),e(prime)(pol-n)p) reaction at three values of Q 2 [viz., 0.45, 1.15 and 1.47 (GeV/c) 2 ] in Hall C of the Thomas Jefferson National Accelerator Facility. Preliminary data indicate that G En follows the Galster parameterization up to Q 2 = 1.15 (GeV/c) 2 and appears to rise above the Galster parameterization at Q 2 = 1.47 (GeV/c) 2
DEFF Research Database (Denmark)
Jouffroy, Jerome; Lottin, Jacques
2002-01-01
For original paper see T.I.Fossen and M.Blanke, ibid., vol.25, pp.241-55 (2000). In the work presented by Fossen and Blanke, a nonlinear observer for estimation of propeller axial flow velocity for UUVs was introduced. The proof of the convergence behavior of the observer was carried out with a L...
Helium Compton Form Factor Measurements at CLAS
Energy Technology Data Exchange (ETDEWEB)
Voutier, Eric J.-M. [Laboratoire de Physique Subatomique et Cosmologie
2013-07-01
The distribution of the parton content of nuclei, as encoded via the generalized parton distributions (GPDs), can be accessed via the deeply virtual Compton scattering (DVCS) process contributing to the cross section for leptoproduction of real photons. Similarly to the scattering of light by a material, DVCS provides information about the dynamics and the spatial structure of hadrons. The sensitivity of this process to the lepton beam polarization allows to single-out the DVCS amplitude in terms of Compton form factors that contain GPDs information. The beam spin asymmetry of the $^4$He($\\vec {\\mathrm e}$,e$' \\gamma ^4$He) process was measured in the experimental Hall B of the Jefferson Laboratory to extract the real and imaginary parts of the twist-2 Compton form factor of the $^4$He nucleus. The experimental results reported here demonstrate the relevance of this method for such a goal, and suggest the dominance of the Bethe-Heitler amplitude to the unpolarized process in the kinematic range explored by the experiment.
Png, Wan Yu; Kwan, Yu Heng; Lee, Yi Xuan; Lim, Ka Keat; Chew, Eng Hui; Lui, Nai Lee; Tan, Chuen Seng; Thumboo, Julian; Østbye, Truls; Fong, Warren
2018-04-05
The aim of this study was to examine if patients' sociodemographic, clinical characteristics, and patient-reported outcomes were associated with biologics initiation in patients with axial spondyloarthritis in Singapore. Data from a dedicated registry from a tertiary referral center in Singapore from January 2011 to July 2016 were used. Initiation of first biologics was the main outcome of interest. Logistic regression analyses were used to explore the association of various factors on biologics initiation. Of 189 eligible patients (aged 37.7 ± 13.3 years; 76.2% were males), 30 (15.9 %) were started on biologics during follow-up. In the multivariable analysis model, age (odds ratio [OR]; 0.93; 95% confidence interval [CI], 0.89-0.98; P < 0.01), mental component summary score of Short-Form 36 Health Survey (OR, 0.18; 95% CI, 0.03-0.89; P = 0.04), erythrocyte sedimentation rate (OR, 1.02; 95% CI, 1.00-1.04; P = 0.02), presence of peptic ulcer disease (OR, 10.4; 95% CI, 2.21-48.8; P < 0.01), and lack of good response to nonsteroidal anti-inflammatory drugs (OR, 4.44; 95% CI, 1.63-12.1; P < 0.01) were found to be associated with biologics initiation. Age, erythrocyte sedimentation rate, mental component summary score, comorbidities of peptic ulcer disease, and responsiveness to nonsteroidal anti-inflammatory drugs were associated with biologics initiation. It is essential that clinicians recognize these factors in order to optimize therapy.
Pion transition form factor in k{sub T} factorization
Energy Technology Data Exchange (ETDEWEB)
Li, Hsiang-nan [Academica Sinica, Taipei, Taiwan (China). Inst. of Physics; Tsing-Hua Univ., Hsinchu, Taiwan (China). Dept. of Phyiscs; National Cheng-Kung Univ., Tainan, Taiwan (China). Dept. of Physics; National Cheng-Chi Univ, Taipei, Taiwan (China). Inst. of Applied Physics; Mishima, Satoshi [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
2009-07-15
It has been pointed out that the recent BaBar data on the {pi}{gamma}{sup *} {yields} {gamma} transition form factor F{sub {pi}}{sub {gamma}}(Q{sup 2}) at low (high) momentum transfer squared Q{sup 2} indicate an asymptotic (flat) pion distribution amplitude. These seemingly contradictory observations can be reconciled in the k{sub T} factorization theorem: the increase of the measured Q{sup 2}FF{sub {pi}}{sub {gamma}}(Q{sup 2}) for Q{sup 2} > 10 GeV{sup 2} is explained by convoluting a k{sub T} dependent hard kernel with a flat pion distribution amplitude, k{sub T} being a parton transverse momentum. The low Q{sup 2} data are accommodated by including the resummation of {alpha}{sub s} ln{sup 2}x, x being a parton momentum fraction, which provides a stronger suppression at the endpoints of x. The next-to-leading-order correction to the pion transition form factor is found to be less than 20% in the considered range of Q{sup 2}. (orig.)
Explicit boundary form factors: The scaling Lee–Yang model
Energy Technology Data Exchange (ETDEWEB)
Hollo, L. [MTA Lendület Holographic QFT Group, Wigner Research Centre for Physics, P.O.B. 49, H-1525 Budapest 114 (Hungary); Laczko, Z.B. [Roland Eötvös University, Pázmány Péter sétány 1/A, 1117 Budapest (Hungary); Bajnok, Z. [MTA Lendület Holographic QFT Group, Wigner Research Centre for Physics, P.O.B. 49, H-1525 Budapest 114 (Hungary)
2014-09-15
We provide explicit expressions for boundary form factors in the boundary scaling Lee–Yang model for operators with the mildest ultraviolet behavior for all integrable boundary conditions. The form factors of the boundary stress tensor take a determinant form, while the form factors of the boundary primary field contain additional explicit polynomials.
DEFF Research Database (Denmark)
Witting, Nanna; Andersen, Linda K; Vissing, John
2016-01-01
Classically, myopathies are categorized according to limb or cranial nerve muscle affection, but with the growing use of magnetic resonance imaging it has become evident that many well-known myopathies have significant involvement of the axial musculature. New disease entities with selective axial...
Electroproduction and electromagnetic form factor of π mesons
International Nuclear Information System (INIS)
Cochard, G.
1975-01-01
The theory of the pion electromagnetic form factor (space-time extension of π mesons, electromagnetic mean squared radius, form factor and strong interactions) is presented and pion electroproduction (virtual photoproduction cross sections, models using dispersion relations, Kessler and Cochard graphic model) is studied. The relation between the pion electromagnetic form factor and electroproduction is then analyzed [fr
MesonNet Workshop on Meson Transition Form Factors
Eidelman, S; Hanhart, C; Kubis, B; Kupsc, A; Leupold, S; Moskal, P; Schadmand, S
2012-01-01
The mini-proceedings of the Workshop on Meson Transition Form Factors held in Cracow from May 29th to 30th, 2012 introduce the meson transition form factor project with special emphasis on the interrelations between the various form factors (on-shell, single off-shell, double off-shell). Short summaries of the talks presented at the workshop follow.
Nucleon form factors and couplings with N_{f}=2+1 Wilson fermions
Djukanovic, D.; Harris, T.; von Hippel, G.; Junnarkar, P.; Meyer, H. B.; Wittig, H.
We present updated results on the nucleon electromagnetic form factors and axial coupling calculated using CLS ensembles with $N_\\mathrm{f}=2+1$ dynamical flavours of Wilson fermions. The measurements are performed on large, fine lattices with a pseudoscalar mass reaching down to 200 MeV. The truncated-solver method is employed to reduce the variance of the measurements. Estimation of the matrix elements is challenging due to large contamination from excited states and further investigation is necessary to bring these effects under control.
Energy Technology Data Exchange (ETDEWEB)
Chambon, Richard [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier / CNRS-IN2P3, 53 Avenue des Martyrs, F-38026 Grenoble (France)
2007-01-15
To face the increasing world power demand the world nuclear sector must be continuously updated and developed as well. Thus reactors of new types are introduced and advanced fuel cycles are proposed. The technological and economic feasibility and the transition of the present power park to a renewed park require thorough studies and scenarios, which are highly dependent on the reactor performances. The conversion rate and cycle span between recharging are important parameters in the scenarios studies. In this frame, we have studied the utilisation of thorium in the CANDU type reactors and particularly the influence of axial form of the flux, i.e. of the recharging mode, on the conversion rate and duration of the cycle between recharging. The results show that up to a first approximation the axial form of the flux resulting from the neutron transport calculations for assessing the conversion rate is not necessary to be taken into account. However the time span between recharging differs up to several percents if the axial form of the flux is taken into consideration in transport calculations. Thus if the burnup or the recharging frequency are parameters which influence significantly the deployment scenarios of a nuclear park an approach more refined than a simple transport evolution in a typical cell/assembly is recommended. Finally, the results of this study are not more general than for the assumed conditions but they give a thorough calculation method valid for any recharging/fuel combination in a CANDU type reactor.
Magnetic form factors of rare earth ions
International Nuclear Information System (INIS)
Deckman, H.W.
1976-01-01
The magnetic scattering of neutrons by atoms has been investigated by exploiting its similarity to the radiation problem in spectroscopy. Expressions for the magnetic scattering amplitude were developed for cases in whcih an atom in the l/sup n/ electronic configuration is described either by a relativistic or nonrelativistic Hamiltonian. For each of these cases, it has been shown that the magnetic scattering amplitude can be expressed in terms of relativistic or nonrelativistic matrix elements of magnetic and electric multipole operators. For a nonrelativistic atom, the calculation of these matrix elements has been separated into evaluating radial matrix elements and matrix elements of Racah tensors W/(sup 0,k)k/ and W/(sup 1,k')k/. For a relativistic atom the effective operator approach has been used to define effective multipole operators so that a relativistic result is obtained by taking matrix elements of these effective operators between nonrelativistic states of the atom. The calculation of matrix elements of these effective operators has been reduced to evaluating relativistic radial integrals and matrix elements of the Racah tensors taken between nonrelativistic states of the atom. It is shown tha for the case of elastic scattering by either a relativistic or nonrelativistic atom in single Russel-Saunders state, the magnetic scattering amplitude can be written in the conventional form p(vector q)vector q/sub m/.vector sigma. General expressions for p(vector q) as well as elastic magnetic form factorshave been obtained. The formalism has been illustrated throughout by applying it to the case of scattering by rare earth ions
Sandrock, H.E.
1982-05-06
Static axial mixing apparatus includes a plurality of channels, forming flow paths of different dimensions. The axial mixer includes a flow adjusting device for adjustable selective control of flow resistance of various flow paths in order to provide substantially identical flows through the various channels, thereby reducing nonuniform coating of interior surfaces of the channels. The flow adjusting device may include diaphragm valves, and may further include a pressure regulating system therefor.
THE FACTORS FORMING QUALITY OF GRANULATED SUGAR
Directory of Open Access Journals (Sweden)
N. G. Kulneva
2015-01-01
Full Text Available Sugar, with good taste and high caloric, is one of the most popular human food. Consumers sugar must be sure that the sugar under normal conditions of use is of high quality and is not harmful to the health of the product. One reason for the decline in the quality of sugar is bacterial contamination. This is because the sugar industry products are good targets for the development of different groups of microorganisms, e.g., Bacillus subtilis, Clostridium perfringes, Leuconostoc dextranicum, Torula alba, Pseudomonas fluorescens, Sarcina lutea and others. These organisms are affected with beets, and then with sugar beet chips and diffusion juice fall into the processing line of sugar production. Their number in the diffusion juice varies and depends on many facto rs such as the quality of raw materials, the quality of cleaning beet root colonization of transporter-washing and the supply of water to the diffusion process, the temperature of the diffusion and others. In the diffusion unit has the most favorable conditions for the development of micro-organisms. Some of them, especially resistant bacteria and thermophilic bacteria or their spores, forming a capsule which protects against external influences occur in the final product sugar. When injected into the fresh crop of product (juice, syrup, they begin to multiply rapidly, causing difficulties in the process. The higher seeding beet microorganisms, the more they decompose and emit sucrose metabolism byproducts. To reduce the negative impact of microbiological and reduce losses from decomposition of sucrose conducted research on the possibility of using chlorine-containing substances in the sugar industry. It was established experimentally that the investigated chlorinated drug has bacteriostatic action and can be recommended for use in sugar beet production.
Asymptotical behaviour of pion electromagnetic form factor in QCD
International Nuclear Information System (INIS)
Efremov, A.V.; Radyushkin, A.V.
1978-01-01
In the framework of the renormalizable quantum field theory a new approach is developed to the investigation of asymptotical behaviour of two-particle bound state electromagnetic form factor. It is shown that the behaviour of the pion EM form factor in quantum chromodynamics at sufficiently large momentum transfers is controlled by the short-distance dynamics only. The formula is obtained which expresses the asymptotical behaviour of the pion form factor in terms of the fundamental constants of the theory
Analytical evaluation of atomic form factors: Application to Rayleigh scattering
Energy Technology Data Exchange (ETDEWEB)
Safari, L., E-mail: laleh.safari@ist.ac.at [IST Austria (Institute of Science and Technology Austria), Am Campus 1, 3400 Klosterneuburg (Austria); Department of Physics, University of Oulu, Box 3000, FI-90014 Oulu (Finland); Santos, J. P. [Laboratório de Instrumentação, Engenharia Biomédica e Física da Radiação (LIBPhys-UNL), Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Amaro, P. [Laboratório de Instrumentação, Engenharia Biomédica e Física da Radiação (LIBPhys-UNL), Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Physikalisches Institut, Universität Heidelberg, D-69120 Heidelberg (Germany); Jänkälä, K. [Department of Physics, University of Oulu, Box 3000, FI-90014 Oulu (Finland); Fratini, F. [Department of Physics, University of Oulu, Box 3000, FI-90014 Oulu (Finland); Institute of Atomic and Subatomic Physics, TU Wien, Stadionallee 2, 1020 Wien (Austria); Departamento de Física, Instituto de Ciências Exatas, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG (Brazil)
2015-05-15
Atomic form factors are widely used for the characterization of targets and specimens, from crystallography to biology. By using recent mathematical results, here we derive an analytical expression for the atomic form factor within the independent particle model constructed from nonrelativistic screened hydrogenic wave functions. The range of validity of this analytical expression is checked by comparing the analytically obtained form factors with the ones obtained within the Hartee-Fock method. As an example, we apply our analytical expression for the atomic form factor to evaluate the differential cross section for Rayleigh scattering off neutral atoms.
Form factors of charged hadrons and quantum chromodynamics
International Nuclear Information System (INIS)
Saleem, M.; Fazal-e-Aleem; Rashid, H.; Azhar, I.A.; Rafique, M.
1988-01-01
A new parametrization G/sup New//sub p/ of the proton form factor is proposed. It is shown that this and the conventional parametrization G/sup V//sub π/ = (1-t/m 2 /sub p/) -1 of the pion form factor are consistent with the experimental data wherever available, with lattice-QCD-based computations for small -t, and with perturbative QCD calculations for large -t. The hyperon form factors computed by using lattice QCD are also parametrized. The features of these form factors most relevant to the Chou-Yang Model are also discussed
New methods for B meson decay constants and form factors from lattice NRQCD
Hughes, C.; Davies, C. T. H.; Monahan, C. J.; Hpqcd Collaboration
2018-03-01
We determine the normalization of scalar and pseudoscalar current operators made from nonrelativistic b quarks and highly improved staggered light quarks in lattice quantum chromodynamics (QCD) through O (αs) and ΛQCD/mb. We use matrix elements of these operators to extract B meson decay constants and form factors, and then compare to those obtained using the standard vector and axial-vector operators. This provides a test of systematic errors in the lattice QCD determination of the B meson decay constants and form factors. We provide a new value for the B and Bs meson decay constants from lattice QCD calculations on ensembles that include u , d , s , and c quarks in the sea and those that have the u /d quark mass going down to its physical value. Our results are fB=0.196 (6 ) GeV , fBs=0.236(7 ) GeV , and fB s/fB=1.207 (7 ), agreeing well with earlier results using the temporal axial current. By combining with these previous results, we provide updated values of fB=0.190 (4 ) GeV , fBs=0.229(5 ) GeV , and fB s/fB=1.206 (5 ).
New Methods for B Meson Decay Constants and Form Factors from Lattice NRQCD
Energy Technology Data Exchange (ETDEWEB)
Hughes, C. [Fermilab; Davies, C. T.H. [SUPA, UK; Monahan, C. J. [Washington U., Seattle
2017-11-27
We determine the normalisation of scalar and pseudoscalar current operators made from non-relativistic $b$ quarks and Highly Improved Staggered light quarks in lattice Quantum Chromodynamics (QCD) through $\\mathcal{O}(\\alpha_s)$ and $\\Lambda_{\\text{QCD}}/m_b$. We use matrix elements of these operators to extract $B$ meson decay constants and form factors, then compare to those obtained using the standard vector and axial-vector operators. This provides a test of systematic errors in the lattice QCD determination of the $B$ meson decay constants and form factors. We provide a new value for the $B$ and $B_s$ meson decay constants from lattice QCD calculations on ensembles that include $u$, $d$, $s$ and $c$ quarks in the sea and those which have the $u/d$ quark mass going down to its physical value. Our results are $f_B=0.196(6)$ GeV, $f_{B_s}=0.236(7)$ GeV and $f_{B_s}/f_B =1.207(7)$, agreeing well with earlier results using the temporal axial current. By combining with these previous results, we provide updated values of $f_B=0.190(4)$ GeV, $f_{B_s}=0.229(5)$ GeV and $f_{B_s}/f_B = 1.206(5)$.
Nakai, Yousuke; Isayama, Hiroyuki; Kawakubo, Kazumichi; Kogure, Hirofumi; Hamada, Tsuyoshi; Togawa, Osamu; Ito, Yukiko; Matsubara, Saburo; Arizumi, Toshihiko; Yagioka, Hiroshi; Takahara, Naminatsu; Uchino, Rie; Mizuno, Suguru; Miyabayashi, Koji; Yamamoto, Keisuke; Sasaki, Takashi; Yamamoto, Natsuyo; Hirano, Kenji; Tada, Minoru; Koike, Kazuhiko
2014-01-01
Tumor involvement to the orifice of cystic duct (OCD) is a risk factor for cholecystitis after self-expandable metallic stent (SEMS) placement, but its prevention is still difficult. We conducted this multicenter analysis to clarify a type of SEMS or a method to place SEMS which would decrease the incidence of cholecystitis after SEMS placement. The incidence of cholecystitis was studied in consecutive patients receiving SEMS for distal malignant biliary obstruction in five tertiary care centers. Multiple logistic regression analysis was performed to evaluate risk factors for cholecystitis. A total of 376 patients who received SEMS placement for distal malignant biliary obstruction were analyzed. Tumor involvement to OCD was diagnosed in 25.3%. Overall incidence of cholecystitis was 6.9%. Cholecystitis was observed in 8.0% of 300 patients with covered SEMS, 16.8% of 95 patients with tumor involvement to OCD, 10.8% of 234 patients with SEMS of high axial force (AF), and 12.0% of 158 patients with SEMS length ≤ 60 mm. In the multivariate analysis, tumor involvement to OCD (odds ratio [OR] 5.40, P cholecystitis in SEMS with high and low AF was 25.0% and 5.0%, respectively. This study with an expanded cohort reconfirmed tumor involvement to OCD as a risk factor for cholecystitis after SEMS placement. SEMS with low AF might decrease cholecystitis. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.
bin Pet, Mokhtar; Sihes, Ahmad Johari Hj
2015-01-01
This study aims to examine the external factors of form six teachers who can influence thinking domain form six teachers in their teaching. This study was conducted using a quantitative approach using questionnaires. A total of 300 form six teacher schools in Johor were chosen as respondents. The findings were obtained as student background…
Molecular form factors in X-ray crystallography
Groenewegen, P.P.M.; Feil, D.
1969-01-01
The calculation of molecular form factors from ab initio molecular electronic wavefunctions is discussed, and a scheme for application to X-ray diffraction structure analysis is given. The method is used to calculate the form factor of the NH+4 molecular ion from three accurate molecular
Proton electromagnetic form factors at large momentum transfer
Indian Academy of Sciences (India)
The electromagnetic form factors of hadrons provide us with fundamental infor- mation about their internal structure. The form factors are measured by elastic scattering of electrons with target protons. The process is assumed to be domi- nated by one-photon exchange. The basic kinematic variables are shown in figure. 1.
X-Ray Form Factor, Attenuation and Scattering Tables
SRD 66 X-Ray Form Factor, Attenuation and Scattering Tables (Web, free access) This database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <= 92).
The pion form factor from analyticity and unitarity
Indian Academy of Sciences (India)
Analyticity and unitarity techniques are employed to estimate Taylor coefficients of the pion electromagnetic form factor at = 0 by exploiting the recently evaluated two-pion contribution to the muon ( − 2) and the phase of the pion electromagnetic form factor in the elastic region, known from scattering by ...
Nucleon form factors in dispersively improved chiral effective field theory: Scalar form factor
Alarcón, J. M.; Weiss, C.
2017-11-01
We propose a method for calculating the nucleon form factors (FFs) of G -parity-even operators by combining chiral effective field theory (χ EFT ) and dispersion analysis. The FFs are expressed as dispersive integrals over the two-pion cut at t >4 Mπ2 . The spectral functions are obtained from the elastic unitarity condition and expressed as products of the complex π π →N N ¯ partial-wave amplitudes and the timelike pion FF. χ EFT is used to calculate the ratio of the partial-wave amplitudes and the pion FF, which is real and free of π π rescattering in the t channel (N /D method). The rescattering effects are then incorporated by multiplying with the squared modulus of the empirical pion FF. The procedure results in a marked improvement compared to conventional χ EFT calculations of the spectral functions. We apply the method to the nucleon scalar FF and compute the scalar spectral function, the scalar radius, the t -dependent FF, and the Cheng-Dashen discrepancy. Higher-order chiral corrections are estimated through the π N low-energy constants. Results are in excellent agreement with dispersion-theoretical calculations. We elaborate several other interesting aspects of our method. The results show proper scaling behavior in the large-Nc limit of QCD because the χ EFT calculation includes N and Δ intermediate states. The squared modulus of the timelike pion FF required by our method can be extracted from lattice QCD calculations of vacuum correlation functions of the operator at large Euclidean distances. Our method can be applied to the nucleon FFs of other operators of interest, such as the isovector-vector current, the energy-momentum tensor, and twist-2 QCD operators (moments of generalized parton distributions).
Comments on electromagnetic form factors of the nucleon
International Nuclear Information System (INIS)
Sachs, R.G.; Wali, K.C.
1989-01-01
This paper draws the concept of nucleon form factors further to consider the electromagnetic aspect based on the magnetic moment of the nucleon. These are seen as valid physical interpretations of form factors in electron-nucleon interactions. A linear combination of two functions, associated with charge radius, is derived, which agreed well with experimental results. The paper also expands the specific form to include relativistic cases and consider appropriate frames of reference. (UK)
International Nuclear Information System (INIS)
Park, N.W.; Schechter, J.; Weigel, H.
1989-01-01
The vanishing of the form factor of the SU(3) single axial current is shown to be stable under the addition of derivative type symmetry breaking terms in the SU(3) Skyrme model. We find that treating the collective hamiltonian exactly dramatically lowers the predicted form factor for the strange quark axial current. Nevertheless, agreement with the EMC experiment is maintained. (orig.)
Power correction to the asymptotics of the pion electromagnetic form factor
International Nuclear Information System (INIS)
Geshkenbein, B.V.; Terentyev, M.V.
1982-01-01
The contribution of the power correction approximately (μ 2 /Q 2 ) 2 enhanced by the factor approximately μ 2 /anti m 2 , to the pion form factor (FF) is calculated (here μ is the pion mass, anti m=1/2(msub(u)+msub(α)) is the mean value of the u- and d-quark masses, Q 2 =-(p-p') 2 > 0, where p, p' are meson momenta at initial and final state. It is shown that the only source of large corrections is due to the contribution of the local pseudoscalar current. The main (approximately 1/Q 2 ) asymptotics of FF associated with the axial current contribution, is derived. The contribution (approximately 1/Q 4 ) of the pseudoscalar current is calculated
Absorptive form factors for high-energy electron diffraction
International Nuclear Information System (INIS)
Bird, D.M.; King, Q.A.
1990-01-01
The thermal diffuse scattering contribution to the absorptive potential in high-energy electron diffraction is calculated in the form of an absorptive contribution to the atomic form factor. To do this, the Einstein model of lattice vibrations is used, with isotropic Debye-Waller factors. The absorptive form factors are calculated as a function of scattering vector s and temperature factor M on a grid which enables polynomial interpolation of the results to be accurate to better than 2% for much of the ranges 0≤Ms 2 ≤6 and 0≤M≤2 A 2 . The computed values, together with an interpolation routine, have been incorporated into a Fortran subroutine which calculates both the real and absorptive form factors for 54 atomic species. (orig.)
Electromagnetic form factors at large momenta from lattice QCD
International Nuclear Information System (INIS)
Chambers, Alexander J.; Dragos, J.; Michigan State Univ., East Lansing, MI; Horsley, R.
2017-01-01
Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate hadronic form factors in lattice QCD at momenta much higher than previously accessible. Our simulations are performed on a single set of gauge configurations with three flavours of degenerate mass quarks corresponding to m π ∼470 MeV. We are able to determine the electromagnetic form factors of the pion and nucleon up to approximately 6 GeV 2 , with results for G E /G M in the proton agreeing well with experimental results.
A note on connected formula for form factors
He, Song; Liu, Zhengwen
2016-12-01
In this note we study the connected prescription, originally derived from Witten's twistor string theory, for tree-level form factors in N = 4 super-Yang-Mills theory. The construction is based on the recently proposed four-dimensional scattering equations with n massless on-shell states and one off-shell state, which we expect to work for form factors of general operators. To illustrate the universality of the prescription, we propose compact formulas for super form factors with chiral stress-tensor multiplet operator, and bosonic ones with scalar operators Tr( ϕ m ) for arbitrary m.
A note on connected formula for form factors
Energy Technology Data Exchange (ETDEWEB)
He, Song [CAS Key Laboratory of Theoretical Physics,Institute of Theoretical Physics, Chinese Academy of Sciences,Beijing 100190 (China); Liu, Zhengwen [Center for Cosmology, Particle Physics and Phenomenology (CP3),Université catholique de Louvain,B-1348 Louvain-la-Neuve (Belgium)
2016-12-02
In this note we study the connected prescription, originally derived from Witten’s twistor string theory, for tree-level form factors in N=4 super-Yang-Mills theory. The construction is based on the recently proposed four-dimensional scattering equations with n massless on-shell states and one off-shell state, which we expect to work for form factors of general operators. To illustrate the universality of the prescription, we propose compact formulas for super form factors with chiral stress-tensor multiplet operator, and bosonic ones with scalar operators Tr(ϕ{sup m}) for arbitrary m.
Form factors and QCD in spacelike and timelike regions
International Nuclear Information System (INIS)
Bakulev, A. P.; Radyushkin, A. V.; Stefanis, N. G.
2000-01-01
We analyze the basic hard exclusive processes, the πγ * γ-transition and the pion and nucleon electromagnetic form factors, and discuss the analytic continuation of QCD formulas from the spacelike q 2 2 >0 of the relevant momentum transfers. We describe the construction of the timelike version of the coupling constant α s . We show that due to the analytic continuation of the collinear logarithms, each eigenfunction of the evolution equation acquires a phase factor and investigate the resulting interference effects which are shown to be very small. We find no sources for the K-factor-type enhancements in the perturbative QCD contribution to the hadronic form factors. To study the soft part of the pion electromagnetic form factor, we use a QCD sum rule inspired model and show that there are noncanceling Sudakov double logarithms which result in a K-factor-type enhancement in the timelike region
Corli, Justine; Flipo, René-Marc; Philippe, Peggy; Bera-Louville, Anne; Béhal, Hélène; Wibaux, Cécile; Paccou, Julien
2015-12-01
The purpose of this study was to (1) evaluate baseline characteristics of nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) treated with tumor necrosis factor-α inhibitors (TNFi), (2) assess the response to first TNFi treatment, and (3) compare drug-survival duration and rates. Inclusion criteria were patients with axSpA who initiated first TNFi treatment between April 2001 and July 2014 and were followed up for at least 3 months. Efficacy criteria were an improvement of at least 2 points (on a 0-10 scale) or a 50% improvement in the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI). Baseline characteristics, responses at 12 months, and drug survival were compared between AS and nr-axSpA. A total of 361 patients were included in the study (AS, n = 263 and nr-axSpA, n = 98). Patients with AS were more often men (65.02% vs 45.92%, p = 0.001) and had longer symptom duration (11.71 ± 9.52 vs 7.34 ± 9.30 yrs, p Treatment response and drug survival were similar in patients with AS and nr-axSpA after first TNFi initiation.
Directory of Open Access Journals (Sweden)
Gunjan Y. Gandhi
2012-01-01
Full Text Available We report the case of a 66-year-old woman with tumor-induced osteomalacia (TIO caused by fibroblast growth factor 23 (FGF-23 secreting mesenchymal tumor localized in a lumbar vertebra and review other cases localized to the axial skeleton. She presented with nontraumatic low back pain and spontaneous bilateral femur fractures. Laboratory testing was remarkable for low serum phosphorus, phosphaturia, and significantly elevated serum FGF-23 level. Magnetic resonance imaging (MRI of the lumbar spine showed a focal lesion in the L-4 vertebra which was hypermetabolic on positron emission tomography (PET scan. A computed tomography (CT guided needle biopsy showed a low grade spindle cell neoplasm with positive FGF-23 mRNA expression by reverse transcriptase polymerase chain reaction (RT-PCR, confirming the diagnosis of a phosphaturic mesenchymal tumor mixed connective tissue variant (PMTMCT. The patient elected to have surgery involving anterior resection of L-4 vertebra with subsequent normalization of serum phosphorus. Including the present case, we identified 12 cases of neoplasms localized to spine causing TIO. To our knowledge, this paper represents the first documented case of lumbar vertebra PMT causing TIO. TIO is a rare metabolic bone disorder that carries a favorable prognosis. When a lesion is identifiable, surgical intervention is typically curative.
Hadronic Form Factors in Asymptotically Free Field Theories
Gross, D. J.; Treiman, S. B.
1974-01-01
The breakdown of Bjorken scaling in asymptotically free gauge theories of the strong interactions is explored for its implications on the large q{sup 2} behavior of nucleon form factors. Duality arguments of Bloom and Gilman suggest a connection between the form factors and the threshold properties of the deep inelastic structure functions. The latter are addressed directly in an analysis of asymptotically free theories; and through the duality connection we are then led to statements about the form factors. For very large q{sup 2} the form factors are predicted to fall faster than any inverse power of q{sup 2}. For the more modest range of q{sup 2} reached in existing experiments the agreement with data is fairly good, though this may well be fortuitous. Extrapolations beyond this range are presented.
Classical limit of diagonal form factors and HHL correlators
Energy Technology Data Exchange (ETDEWEB)
Bajnok, Zoltan [MTA Lendület Holographic QFT Group, Wigner Research Centre,H-1525 Budapest 114, P.O.B. 49 (Hungary); Janik, Romuald A. [Institute of Physics, Jagiellonian University,ul. Łojasiewicza 11, 30-348 Kraków (Poland)
2017-01-16
We propose an expression for the classical limit of diagonal form factors in which we integrate the corresponding observable over the moduli space of classical solutions. In infinite volume the integral has to be regularized by proper subtractions and we present the one, which corresponds to the classical limit of the connected diagonal form factors. In finite volume the integral is finite and can be expressed in terms of the classical infinite volume diagonal form factors and subvolumes of the moduli space. We analyze carefully the periodicity properties of the finite volume moduli space and found a classical analogue of the Bethe-Yang equations. By applying the results to the heavy-heavy-light three point functions we can express their strong coupling limit in terms of the classical limit of the sine-Gordon diagonal form factors.
Infrared photons and gluons and the electromagnetic quark form factor
International Nuclear Information System (INIS)
Scholz, B.
1982-01-01
A method for a consistent treatment of the infrared behaviour of QED and QCD is presented. As an application of the method the calculation of the electromagnetic quark form factor is discussed. (M.F.W.)
The connected prescription for form factors in twistor space
Energy Technology Data Exchange (ETDEWEB)
Brandhuber, A.; Hughes, E.; Panerai, R.; Spence, B.; Travaglini, G. [Centre for Research in String Theory, School of Physics and Astronomy,Queen Mary University of London,Mile End Road, London E1 4NS (United Kingdom)
2016-11-23
We propose a connected prescription formula in twistor space for all tree-level form factors of the stress tensor multiplet operator in N=4 super Yang-Mills, which is a generalisation of the expression of Roiban, Spradlin and Volovich for superamplitudes. By introducing link variables, we show that our formula is identical to the recently proposed four-dimensional scattering equations for form factors. Similarly to the case of amplitudes, the link representation of form factors is shown to be directly related to BCFW recursion relations, and is considerably more tractable than the scattering equations. We also discuss how our results are related to a recent Grassmannian formulation of form factors, and comment on a possible derivation of our formula from ambitwistor strings.
The connected prescription for form factors in twistor space
Brandhuber, A.; Hughes, E.; Panerai, R.; Spence, B.; Travaglini, G.
2016-11-01
We propose a connected prescription formula in twistor space for all tree-level form factors of the stress tensor multiplet operator in {N} = 4 super Yang-Mills, which is a generalisation of the expression of Roiban, Spradlin and Volovich for superamplitudes. By introducing link variables, we show that our formula is identical to the recently proposed four-dimensional scattering equations for form factors. Similarly to the case of amplitudes, the link representation of form factors is shown to be directly related to BCFW recursion relations, and is considerably more tractable than the scattering equations. We also discuss how our results are related to a recent Grassmannian formulation of form factors, and comment on a possible derivation of our formula from ambitwistor strings.
Electromagnetic form factors at large momenta from lattice QCD
Chambers, A. J.; Dragos, J.; Horsley, R.; Nakamura, Y.; Perlt, H.; Pleiter, D.; Rakow, P. E. L.; Schierholz, G.; Schiller, A.; Somfleth, K.; Stüben, H.; Young, R. D.; Zanotti, J. M.; Qcdsf/Ukqcd/Cssm Collaborations
2017-12-01
Accessing hadronic form factors at large momentum transfers has traditionally presented a challenge for lattice QCD simulations. Here, we demonstrate how a novel implementation of the Feynman-Hellmann method can be employed to calculate hadronic form factors in lattice QCD at momenta much higher than previously accessible. Our simulations are performed on a single set of gauge configurations with three flavors of degenerate mass quarks corresponding to mπ≈470 MeV . We are able to determine the electromagnetic form factors of the pion and nucleon up to approximately 6 GeV2 , with results for the ratio of the electric and magnetic form factors of the proton at our simulated quark mass agreeing well with experimental results.
Electromagnetic form factors of baryons in an algebraic approach
International Nuclear Information System (INIS)
Bijker, R.; Leviatan, A.
1999-01-01
We present a simultaneous analysis of elastic and transition form factors of the nucleon. The calculations are performed in the framework of an algebraic model of baryons. Effects of meson cloud couplings are considered. (Author)
Electromagnetic form factors of baryons in an algebraic approach
Energy Technology Data Exchange (ETDEWEB)
Bijker, R. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510 Mexico D.F. (Mexico); Leviatan, A. [Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)
1999-07-01
We present a simultaneous analysis of elastic and transition form factors of the nucleon. The calculations are performed in the framework of an algebraic model of baryons. Effects of meson cloud couplings are considered. (Author)
Charm and bottom hadronic form factors with QCD sum rules
International Nuclear Information System (INIS)
Bracco, M. E.; Rodrigues, B. O.; Cerqueira, A. Jr.
2013-01-01
We present a brief review of some calculations of form factors and coupling constants in vertices with charm and bottom mesons in the framework of QCD sum rules. We first discuss the motivation for this work, describing possible applications of these form factors to charm and bottom decays processes. We first make a summarize of the QCD sum rules method. We give special attention to the uncertainties of the method introducing by the intrinsic variation of the parameters. Finally we conclude.
Pion form factor at intermediate momentum transfer in QCD
International Nuclear Information System (INIS)
Ioffe, B.L.; Smilga, A.V.
1982-01-01
A general method is proposed for the QCD based calculation of form factors at intermediate Q 2 and of the partial widths of the low-lying meson resonances. The basic idea is to use QCD sum rules for the vertex functions. With this method, the pion form factor at 0.5 2 2 is calculated. The results are in good agreement with experiment
Electromagnetic form factors in a collective model of the nucleon
Energy Technology Data Exchange (ETDEWEB)
Bijker, R.; Iachello, F.; Leviatan, A. [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, 04510 (Mexico)]|[Distrito Federale (Mexico)]|[Center for Theoretical Physics, Sloane Laboratory, Yale University, New Haven, Connecticut 06520-8120 (United States)]|[Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)
1996-10-01
We study the electromagnetic form factors of the nucleon in a collective model of baryons. Using the algebraic approach to hadron structure, we derive closed expressions for both elastic and transition form factors, and consequently for the helicity amplitudes that can be measured in electro- and photoproduction. Effects of spin-flavor symmetry breaking and of swelling of hadrons with increasing excitation energy are considered. {copyright} {ital 1996 The American Physical Society.}
Electromagnetic form factors in a collective model of the nucleon
International Nuclear Information System (INIS)
Bijker, R.; Iachello, F.; Leviatan, A.
1996-01-01
We study the electromagnetic form factors of the nucleon in a collective model of baryons. Using the algebraic approach to hadron structure, we derive closed expressions for both elastic and transition form factors, and consequently for the helicity amplitudes that can be measured in electro- and photoproduction. Effects of spin-flavor symmetry breaking and of swelling of hadrons with increasing excitation energy are considered. copyright 1996 The American Physical Society
Form factors of the finite quantum XY-chain
International Nuclear Information System (INIS)
Iorgov, Nikolai
2011-01-01
Explicit factorized formulas for the matrix elements (form factors) of the spin operators σ x and σ y between the eigenvectors of the Hamiltonian of the finite quantum periodic XY-chain in a transverse field were derived. The derivation is based on the relations between three models: the model of quantum XY-chain, Ising model on 2D lattice and N = 2 Baxter-Bazhanov-Stroganov τ (2) -model. Due to these relations we transfer the formulas for the form factors of the latter model recently obtained by the use of separation of variables method to the model of quantum XY-chain. Hopefully, the formulas for the form factors will help in analysis of multipoint dynamic correlation functions at a finite temperature. As an example, we re-derive the asymptotics of the two-point correlation function in the disordered phase without the use of the Toeplitz determinants and the Wiener-Hopf factorization method.
STABILITY ANALYSIS OF ORTHOTROPIC RECTANGULAR PLATES USING THE FORM FACTOR
Directory of Open Access Journals (Sweden)
Savin Sergey Yur’evich
2018-01-01
Full Text Available The article describes the problem of stability of elastic orthotropic rectangular plates for the case when two opposite sides are simply supported, and two other sides have boundary with either simple supports or fixed supports, which are arbitrarily combined. The plate that is simply supported all over the contour is not considered in the article since the authors described it in the earlier publication. The external load is uniformly distributed along the side and is applied to the shorter side of the plate. To solve the stability problem, the authors use an approximate analytical method - the form factor interpolation method, which is based on the functional relationship between an integral geometric parameter of the mid-plane surface (the form factor and an integral mechanical parameter (the critical force of buckling. Subject: stability of elastic orthotropic rectangular plates for the case when two opposite sides are simply supported and two other sides have combination of simple supports and fixed supports arbitrarily combined. Materials and methods: the form factor interpolation method (FFIM is used to solve the stability problem of elastic orthotropic rectangular plates. The solutions which were obtained by the FFIM method were compared with the results of calculations by FEM (the program SCAD Office 11.5. Results: for orthotropic rectangular plates with combined boundary conditions, we obtained analytical expressions for critical force surfaces and they depend on an integral geometric parameter - form factor and flexural stiffness ratio. To the authors’ knowledge, these expressions are obtained for the first time. The critical force surface for orthotropic rectangular plates constitutes one of the boundaries of this integral physicomechanical parameter for the entire set of orthotropic plates with arbitrary convex contour. Therefore, this surface can be used for obtaining reference solutions by the form factor interpolation method
Probing confined-quark dynamics via nucleon form factors
International Nuclear Information System (INIS)
The QCD Dyson-Schwinger equations [DSEs] provide the basis for a phenomenology, in which the known large-q 2 behavior of the gluon propagator is extrapolated to small-q 2 via a parameterisation that incorporates the qualitative features of many studies of the gluon DSE. This phenomenology has been successfully applied in the calculation of a wide range of hadron observables; for example: the meson ground state spectrum, the elastic scattering and anomalous transition form factors of pseudoscalar mesons; and the electroproduction of vector mesons. The electromagnetic form factors of the nucleon are calculated using a product Ansatz for the nucleon Fadde'ev amplitude. The preliminary results are encouraging. Isoscalar-scalar and isovector-pseudovector confined diquark correlations are found to provide the dominant contribution to the form factors. The inclusion of the isovector-pseudovector correlation can help describe the electric and magnetic properties of the nucleon
Zero modes method and form factors in quantum integrable models
Directory of Open Access Journals (Sweden)
S. Pakuliak
2015-04-01
Full Text Available We study integrable models solvable by the nested algebraic Bethe ansatz and possessing GL(3-invariant R-matrix. Assuming that the monodromy matrix of the model can be expanded into series with respect to the inverse spectral parameter, we define zero modes of the monodromy matrix entries as the first nontrivial coefficients of this series. Using these zero modes we establish new relations between form factors of the elements of the monodromy matrix. We prove that all of them can be obtained from the form factor of a diagonal matrix element in special limits of Bethe parameters. As a result we obtain determinant representations for form factors of all the entries of the monodromy matrix.
Evaluation of E2 form factor = 24Mg
International Nuclear Information System (INIS)
Marinelli, J.R.; Moreira, J.R.
1988-11-01
Longitudinal and transverse electron scattering form factors for the 2 + state at 1.37 Mev of the 24 Mg nucleus was evaluated with rotational model wavefunctions. Four different approaches were used for the transverse E2 form factor: PHF, cranking model, ridig rotor and irrotational flow. For the nuclear intrinsic wavefunction, the Nilsson model was assumed in all approaches yielding the calculation of the form factor in PWBA and DWBA. The results are discussed and compared with a recent measurement performed with 180 0 electron scattered from this state. The DWBA calculation, taking into account first order corrections shows that PHF and irrotational flow models give the best agreements with the available data and compete in quality with more complex calculation performed under the 'shell model' approach. (author) [pt
The pion form factor from analyticity and unitarity
Indian Academy of Sciences (India)
2012-11-15
Nov 15, 2012 ... Regions in the complex t-plane are isolated where the form factor cannot have zeros. ... t-plane cut along the real axis from the unitarity threshold t+ = 4M2 πto ∞ and is nor- malized to Fπ ... cast the integral equation into a canonical form and derive a determinant (for details, see ref. [2]) which is central to ...
Conservative flight with a varying load factor and closed form ...
Indian Academy of Sciences (India)
The load factor being a control parameter is varied in such a way that it gives rise to closed-form solutions to ... the time t and selecting the path inclination as the new independent variable, set (2) can be transformed to the form dξ ... (5) the following initial conditions are assumed: γi = ξi = ηi = 0, ui = 1,. (6) as a result of which, ...
Master integrals for the four-loop Sudakov form factor
Directory of Open Access Journals (Sweden)
Rutger H. Boels
2016-01-01
Full Text Available The light-like cusp anomalous dimension is a universal function in the analysis of infrared divergences. In maximally (N=4 supersymmetric Yang–Mills theory (SYM in the planar limit, it is known, in principle, to all loop orders. The non-planar corrections are not known in any theory, with the first appearing at the four-loop order. The simplest quantity which contains this correction is the four-loop two-point form factor of the stress tensor multiplet. This form factor was largely obtained in integrand form in a previous work for N=4 SYM, up to a free parameter. In this work, a reduction of the appearing integrals obtained by solving integration-by-parts (IBP identities using a modified version of Reduze is reported. The form factor is shown to be independent of the remaining parameter at integrand level due to an intricate pattern of cancellations after IBP reduction. Moreover, two of the integral topologies vanish after reduction. The appearing master integrals are cross-checked using independent algebraic-geometry techniques explored in the Mint package. The latter results provide the basis of master integrals applicable to generic form factors, including those in Quantum Chromodynamics. Discrepancies between explicitly solving the IBP relations and the MINT approach are highlighted. Remaining bottlenecks to completing the computation of the four-loop non-planar cusp anomalous dimension in N=4 SYM and beyond are identified.
Master integrals for the four-loop Sudakov form factor
Boels, Rutger H.; Kniehl, Bernd A.; Yang, Gang
2016-01-01
The light-like cusp anomalous dimension is a universal function in the analysis of infrared divergences. In maximally (N = 4) supersymmetric Yang-Mills theory (SYM) in the planar limit, it is known, in principle, to all loop orders. The non-planar corrections are not known in any theory, with the first appearing at the four-loop order. The simplest quantity which contains this correction is the four-loop two-point form factor of the stress tensor multiplet. This form factor was largely obtained in integrand form in a previous work for N = 4 SYM, up to a free parameter. In this work, a reduction of the appearing integrals obtained by solving integration-by-parts (IBP) identities using a modified version of Reduze is reported. The form factor is shown to be independent of the remaining parameter at integrand level due to an intricate pattern of cancellations after IBP reduction. Moreover, two of the integral topologies vanish after reduction. The appearing master integrals are cross-checked using independent algebraic-geometry techniques explored in the Mint package. The latter results provide the basis of master integrals applicable to generic form factors, including those in Quantum Chromodynamics. Discrepancies between explicitly solving the IBP relations and the MINT approach are highlighted. Remaining bottlenecks to completing the computation of the four-loop non-planar cusp anomalous dimension in N = 4 SYM and beyond are identified.
Master integrals for the four-loop Sudakov form factor
Energy Technology Data Exchange (ETDEWEB)
Boels, Rutger; Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Yang, Gang [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Chinese Academy of Sciences, Beijing (China). Inst. of Theoretical Physics
2015-08-15
The light-like cusp anomalous dimension is a universal function in the analysis of infrared divergences. In maximally (N=4) supersymmetric Yang-Mills theory (SYM) in the planar limit, it is known, in principle, to all loop orders. The non-planar corrections are not known in any theory, with the first appearing at the four-loop order. Probably the simplest quantity which contains this correction is the four-loop two-point form factor of the stress tensor multiplet. This form factor was obtained in integrand form in a previous work for N=4 SYM, up to a single parameter. In this work, a reduction of the appearing integrals obtained by solving integration-by-parts (IBP) identities using (a tweaked version of) Reduze is reported. The form factor is shown to be independent of the remaining parameter at integrand level due to an intricate pattern of cancellations after IBP reduction. The appearing master integrals are cross-checked using algebraic techniques explored in the Mint package. The latter results provide the basis of master integrals applicable to generic form factors, including those in Quantum Chromodynamics. Remaining bottlenecks to completing the computation of the four-loop non-planar cusp anomalous dimension in N=4 SYM and beyond are identified.
Master integrals for the four-loop Sudakov form factor
International Nuclear Information System (INIS)
Boels, Rutger; Kniehl, Bernd A.; Yang, Gang; Chinese Academy of Sciences, Beijing
2015-08-01
The light-like cusp anomalous dimension is a universal function in the analysis of infrared divergences. In maximally (N=4) supersymmetric Yang-Mills theory (SYM) in the planar limit, it is known, in principle, to all loop orders. The non-planar corrections are not known in any theory, with the first appearing at the four-loop order. Probably the simplest quantity which contains this correction is the four-loop two-point form factor of the stress tensor multiplet. This form factor was obtained in integrand form in a previous work for N=4 SYM, up to a single parameter. In this work, a reduction of the appearing integrals obtained by solving integration-by-parts (IBP) identities using (a tweaked version of) Reduze is reported. The form factor is shown to be independent of the remaining parameter at integrand level due to an intricate pattern of cancellations after IBP reduction. The appearing master integrals are cross-checked using algebraic techniques explored in the Mint package. The latter results provide the basis of master integrals applicable to generic form factors, including those in Quantum Chromodynamics. Remaining bottlenecks to completing the computation of the four-loop non-planar cusp anomalous dimension in N=4 SYM and beyond are identified.
Towards a dispersive determination of the pion transition form factor
Leupold Stefan; Hoferichter Martin; Kubis Bastian; Niecknig Franz; Schneider Sebastian P.
2018-01-01
We start with a brief motivation why the pion transition form factor is interesting and, in particular, how it is related to the high-precision standard-model calculation of the gyromagnetic ratio of the muon. Then we report on the current status of our ongoing project to calculate the pion transition form factor using dispersion theory. Finally we present and discuss a wish list of experimental data that would help to improve the input for our calculations and/or to cross-check our results.
Towards a dispersive determination of the pion transition form factor
Directory of Open Access Journals (Sweden)
Leupold Stefan
2018-01-01
Full Text Available We start with a brief motivation why the pion transition form factor is interesting and, in particular, how it is related to the high-precision standard-model calculation of the gyromagnetic ratio of the muon. Then we report on the current status of our ongoing project to calculate the pion transition form factor using dispersion theory. Finally we present and discuss a wish list of experimental data that would help to improve the input for our calculations and/or to cross-check our results.
Deuteron form factor measurements at low momentum transfers
Directory of Open Access Journals (Sweden)
Schlimme B. S.
2016-01-01
Full Text Available A precise measurement of the elastic electron-deuteron scattering cross section at four-momentum transfers of 0.24 fm−1 ≤ Q ≤ 2.7 fm−1 has been performed at the Mainz Microtron. In this paper we describe the utilized experimental setup and the necessary analysis procedure to precisely determine the deuteron charge form factor from these data. Finally, the deuteron charge radius rd can be extracted from an extrapolation of that form factor to Q2 = 0.
Measurement of the Charged Pion Electromagnetic Form Factor
International Nuclear Information System (INIS)
J. Volmer; David Abbott; H. Anklin; Chris Armstrong; John Arrington; K. Assamagan; Steven Avery; Oliver K. Baker; Henk Blok; C. Bochna; Ed Brash; Herbert Breuer; Nicholas Chant; Jim Dunne; Tom Eden; Rolf Ent; David Gaskell; Ron Gilman; Kenneth Gustafsson; Wendy Hinton; Garth Huber; Hal Jackson; Mark K. Jones; Cynthia Keppel; P.H. Kim; Wooyoung Kim; Andi Klein; Doug Koltenuk; Meme Liang; George Lolos; Allison Lung; David Mack; D. McKee; David Meekins; Joseph Mitchell; H. Mkrtchian; B. Mueller; Gabriel Niculescu; Ioana Niculescu; D. Pitz; D. Potterveld; Liming Qin; Juerg Reinhold; I.K. Shin; Stepan Stepanyan; V. Tadevosian; L.G. Tang; R.L.J. van der Meer; K. Vansyoc; D. Van Westrum; Bill Vulcan; Stephen Wood; Chen Yan; W.X. Zhao; Beni Zihlmann
2001-01-01
Separated longitudinal and transverse structure functions for the reaction 1H(e,eprime pi+)n were measured in the momentum transfer region Q2=0.6-1.6 (GeV/c)**2 at a value of the invariant mass W=1.95 GeV. New values for the pion charge form factor were extracted from the longitudinal cross section by using a recently developed Regge model. The results indicate that the pion form factor in this region is larger than previously assumed and is consistent with a monopole parameterization fitted to very low Q2 elastic data
Pion Electromagnetic Form Factor in Virtuality Distribution Formalism
Energy Technology Data Exchange (ETDEWEB)
Radyushkin, Anatoly V. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Old Dominion Univ., Norfolk, VA (United States)
2016-01-01
We discuss two applications of the {\\it Virtuality Distribution Amplitudes} (VDA) formalism developed in our recent papers. We start with an overview of the main properties of the pion distribution amplitude emphasizing the quantitative measures of its width, and possibility to access them through the pion transition form factor studies. We formulate the basic concepts of the VDA approach and introduce the pion {\\it transverse momentum distribution amplitude} (TMDA) which plays, in a covariant Lagrangian formulation, a role similar to that of the pion wave function in the 3-dimensional Hamiltonian light-front approach. We propose simple factorized models for soft TMDAs, and use them to describe existing data on the pion transition form factor, thus fixing the scale determining the size of the transverse-momentum effects. Finally, we apply the VDA approach to the one-gluon exchange contribution for the pion electromagnetic form factor. We observe a very late $Q^2 \\gtrsim 20$ GeV$^2$ onset of transition to the asymptotic pQCD predictions and show that in the $Q^2 \\lesssim 10$ GeV$^2$ region there is essentially no sensitivity to the shape of the pion distribution amplitude. Furthermore, the magnitude of the one-gluon exchange contribution in this region is estimated to be an order of magnitude below the Jefferson Lab data, thus leaving the Feynman mechanism as the only one relevant to the pion electromagnetic form factor behavior for accessible $Q^2$.
Measurement of the pion form factor at higher energies
Energy Technology Data Exchange (ETDEWEB)
Mack, D.J. [CEBAF, Newport News, VA (United States)
1994-04-01
One of the strongest arguments for increasing the nominal CEBAF beam energy to equal or exceed 6 GeV is that one would be able to make quality high Q{sup 2} measurements of the charged pion form factor.
Nucleon form factors program with SBS at JLAB
Energy Technology Data Exchange (ETDEWEB)
Wojtsekhowski, Bogdan B. [JLAB
2014-12-01
The physics of the nucleon form factors is the basic part of the Jefferson Laboratory program. We review the achievements of the 6-GeV era and the program with the 12- GeV beam with the SBS spectrometer in Hall A, with a focus on the nucleon ground state properties.
Generation of truncated recombinant form of tumor necrosis factor ...
African Journals Online (AJOL)
Generation of truncated recombinant form of tumor necrosis factor receptor-1 to produce cancer vaccine. Hamide Hatamihanza1, Mehrdad Hashemi1*, Azim Akbarzadeh2, Fatemeh. Fotouhi3, Behrokh Farahmand3, Hasan Ebrahimi Shahmabadi4. 1Department of Molecular Genetics, Tehran Medical Branch, Islamic Azad ...
Proton and neutron electromagnetic form factors and uncertainties
Ye, Zhihong; Arrington, John; Hill, Richard J.; Lee, Gabriel
2018-02-01
We determine the nucleon electromagnetic form factors and their uncertainties from world electron scattering data. The analysis incorporates two-photon exchange corrections, constraints on the low-Q2 and high-Q2 behavior, and additional uncertainties to account for tensions between different data sets and uncertainties in radiative corrections.
On form factors and correlation functions in twistor space
Energy Technology Data Exchange (ETDEWEB)
Koster, Laura [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, 12489 Berlin (Germany); Mitev, Vladimir [PRISMA Cluster of Excellence, Institut für Physik, WA THEP,Johannes Gutenberg-Universität Mainz,Staudingerweg 7, 55128 Mainz (Germany); Staudacher, Matthias [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, 12489 Berlin (Germany); Wilhelm, Matthias [Niels Bohr Institute, Copenhagen University,Blegdamsvej 17, 2100 Copenhagen Ø (Denmark)
2017-03-24
In this paper, we continue our study of form factors and correlation functions of gauge-invariant local composite operators in the twistor-space formulation of N=4 super Yang-Mills theory. Using the vertices for these operators obtained in our recent papers (DOI: 10.1103/PhysRevLett.117.011601; 10.1007/JHEP06(2016)162 ), we show how to calculate the twistor-space diagrams for general N{sup k}MHV form factors via the inverse soft limit, in analogy to the amplitude case. For general operators without α-dot indices, we then reexpress the NMHV form factors from the position-twistor calculation in terms of momentum twistors, deriving and expanding on a relation between the two twistor formalisms previously observed in the case of amplitudes. Furthermore, we discuss the calculation of generalized form factors and correlation functions as well as the extension to loop level, in particular providing an argument promised in https://www.doi.org/10.1002/prop.201400085.
Form factors and charge radii in a quantum chromodynamics ...
Indian Academy of Sciences (India)
The results show that charge radii and form factors are quite small for the Coulombic parent compared to the linear parent. Also, the analysis leads to a lower as well as upper bounds on the four-momentum transfer 2, hinting at a workable range of 2 within this approach, which may be useful in future experimental ...
On form factors and correlation functions in twistor space
International Nuclear Information System (INIS)
Koster, Laura; Mitev, Vladimir; Staudacher, Matthias; Wilhelm, Matthias
2017-01-01
In this paper, we continue our study of form factors and correlation functions of gauge-invariant local composite operators in the twistor-space formulation of N=4 super Yang-Mills theory. Using the vertices for these operators obtained in our recent papers (DOI: 10.1103/PhysRevLett.117.011601; 10.1007/JHEP06(2016)162 ), we show how to calculate the twistor-space diagrams for general N k MHV form factors via the inverse soft limit, in analogy to the amplitude case. For general operators without α-dot indices, we then reexpress the NMHV form factors from the position-twistor calculation in terms of momentum twistors, deriving and expanding on a relation between the two twistor formalisms previously observed in the case of amplitudes. Furthermore, we discuss the calculation of generalized form factors and correlation functions as well as the extension to loop level, in particular providing an argument promised in https://www.doi.org/10.1002/prop.201400085.
Numerical study of the lattice meson form factor
International Nuclear Information System (INIS)
Woloshyn, R.M.; Kobos, A.M.
1986-01-01
The electric form factor of the pseudo-Goldstone meson (the generic pion) is calculated in quenched lattice quantum chromodynamics with SU(2) color. Charge radii are calculated for different values of the bare-quark mass. The results are in agreement with the physically reasonable expectation that heavier quarks have distributions of smaller radius
Form factors and charge radii in a quantum chromodynamics ...
Indian Academy of Sciences (India)
Abstract. We use variationally improved perturbation theory (VIPT) for calculating the elas- tic form factors and charge radii of D, Ds,B,Bs and Bc mesons in a quantum chromodynamics. (QCD)-inspired potential model. For that, we use linear-cum-Coulombic potential and opt the. Coulombic part first as parent and then the ...
Radiative corrections in nucleon time-like form factors measurements
Energy Technology Data Exchange (ETDEWEB)
Van de Wiele, Jacques [Universite de Paris-Sud, Institut de Physique Nucleaire, Orsay Cedex (France); Ong, Saro [Universite de Paris-Sud, Institut de Physique Nucleaire, Orsay Cedex (France); Universite de Picardie Jules Verne, Amiens (France)
2013-02-15
The completely general radiative corrections to lowest order, including the final- and initial-state radiations, are studied in proton-antiproton annihilation into an electron-positron pair. Numerical estimates have been made in a realistic configuration of the PANDA detector at FAIR for the proton time-like form factors measurements. (orig.)
Form factors and radiation widths of the giant multipole resonances
International Nuclear Information System (INIS)
Denisov, V.Yu.
1990-01-01
Simple analytic relations for the form factors of inelastic electron scattering in the Born approximation and radiation widths of the isovector and isoscalar giant multipole resonances are derived. The dynamic relationship between the volume and surface density vibrations were taken into account in this calculation. The form factors in the Born approximation were found to be in satisfactory agreement with experimental data in the region of small transferred momenta. The radiation widths of isoscalar multipole resonances increase when the number of nucleons increase as A 1/3 , and for isovector resonances this dependence has the form f(A)A 1/3 , where f(A) is a slowly increasing function of A. Radiation widths well fit the experimental data
Nucleon form factors, generalized parton distributions and quark angular momentum
International Nuclear Information System (INIS)
Diehl, Markus; Kroll, Peter; Regensburg Univ.
2013-02-01
We extract the individual contributions from u and d quarks to the Dirac and Pauli form factors of the proton, after a critical examination of the available measurements of electromagnetic nucleon form factors. From this data we determine generalized parton distributions for valence quarks, assuming a particular form for their functional dependence. The result allows us to study various aspects of nucleon structure in the valence region. In particular, we evaluate Ji's sum rule and estimate the total angular momentum carried by valence quarks at the scale μ=2 GeV to be J u v =0.230 +0.009 -0.024 and J d v =-0.004 +0.010 -0.016 .
Nucleon form factors, generalized parton distributions and quark angular momentum
Energy Technology Data Exchange (ETDEWEB)
Diehl, Markus [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Kroll, Peter [Bergische Univ., Wuppertal (Germany). Fachbereich Physik; Regensburg Univ. (Germany). Institut fuer Theoretische Physik
2013-02-15
We extract the individual contributions from u and d quarks to the Dirac and Pauli form factors of the proton, after a critical examination of the available measurements of electromagnetic nucleon form factors. From this data we determine generalized parton distributions for valence quarks, assuming a particular form for their functional dependence. The result allows us to study various aspects of nucleon structure in the valence region. In particular, we evaluate Ji's sum rule and estimate the total angular momentum carried by valence quarks at the scale {mu}=2 GeV to be J{sup u}{sub v}=0.230{sup +0.009}{sub -0.024} and J{sup d}{sub v}=-0.004{sup +0.010}{sub -0.016}.
Factors Affecting the Form of Substitute Family Care
Directory of Open Access Journals (Sweden)
Monika Chrenková
2015-11-01
Full Text Available Recently, the system of care for endangered children has changed from the institutional as well as legislative point of view. In one of the partial areas of ongoing changes, research activities realised within the Students’ Grant Competition called The Factors Affecting the Form of Substitute Family Care are being focused. We deal with this topic because various forms of substitute family care are distinguished in the Czech Republic, where children are placed for various reasons, but we do not know the correct context of such placements. The main aim of the realised research was to find out the frequency of choosing a given form of placing children in substitute family care according to followed variables. The research sample of the quantitative research was consisted of children placed in one of the forms of substitute family care in the Moravian-Silesian region.
The Factors of Forming the National HR-Management Model
Directory of Open Access Journals (Sweden)
Elena P. Kostenko
2017-12-01
Full Text Available There are some factors considered in this article, which influence the forming of national HR-management model. The group-forming criterion is the nature of factors, that determine the system of HR-management as a system of corporate culture values, norms and rules of organizational behavior, ways of realization some important managing functions and dominating approaches to make decisions. This article shows that the plurality of combinations in different factors leads to forming the unique HR-management model. The geoclimatic factor influences the principles of the labor organization (orientation primarily on individual or collective forms of labor, attitude to the management experience of other countries, attitude to resources, etc., the distribution of labor resources, the level of labor mobility, and the psychosocial type of employee. Models of man's labor behavior are constituted In the process of historical development. Attention is focused on the formation of a national HR-model, such as the conducted socio-economic policy, the characteristics of the institutional environment, economic goals and priorities of the country's development, the level of development and the nature of the national productive forces and economic structures. Much attention was paid to the analysis of the historically formed value system and labor traditions, which influence the approaches to HR-management. As far as religion influences the model of person’s inclusion in labor, motives of labor behavior, management culture of a certain employee, preferred payment etc., we examined how the main traditional religions (Christianity, Islam, Judaism, Buddhism, Confucianism, Hinduism influence the HR-management system in different countries.
Cutilli, T; Corbacelli, A
2009-05-01
The aim of this study was to analyze the physiopathology of the acute cervical injure in the event of mandibular condylar fractures. As in the Part 1, 25 non-consecutive cases of condylar mandibular fractures (16 males and 9 females, mean age: 22.96/range 14-36 years) observed and treated in the Maxillofacial Surgery Department of the University of L'Aquila, have been studied. Types of fractures examined included: unilateral: 19 cases (solitary: 12; associated with other mandibular fractures: 7, homolateral: 2); bilateral: 6 cases (equivalent: 2, not equivalent: 4). A control group was constituted of 10 patients, 5 males and 5 females, aged from 19 to 24 years (mean range: 21.6) suffering from acute isolated cervical distorsion (whiplash). The study has been performed by means of the analysis of X-ray and computed tomography (CT)-CT/3D of the mandibular condylar regions, the occipital-atlanto-axial structures and the cervical region. In all the patients the following constant alterations that link up with these fractures have been observed: the rotation of atlas, the atlanto-axial subluxation and the derangement of the occipital-atlanto-epistropheal joint, homolateral to the side of the mandibular condylar fracture. The cervical spine shows the constant loss of physiological lordosis with hinge between C3 and C4. In the whiplash, as the authors have been able to assess in the control group, there are no alterations of occipital-atlanto-axial joint and the kinetic vector is placed on the longitudinal plane. In the mandibular condylar fractures the kinetic mechanism is completely different regarding the whiplash. The point of entry is the chin and the kinetic vector is oriented down-up, sometimes oblique in the opposite side. Subsequently the kinetic force is transmitted throughout the mandibular structure and causes the condylar or bicondylar fracture. The kinetic vector is placed before on the vertical plane, then on the horizontal plane and later on the vertical
Analytical and unitary approach in mesons electromagnetic form factor applications
International Nuclear Information System (INIS)
Liptaj, A.
2010-07-01
In the dissertation thesis we address several topics related to the domain of particle physics. All of them represent interesting open problems that can be connected to the elastic or transition electromagnetic form factors of mesons, the form factors being the main objects of our interest. Our ambition is to contribute to the solution of these problems and use for that purpose known analytic properties of the form factors and the unitarity condition. These two tools are very powerful in the low energy domain (such as bound states of partons), where the perturbative QCD looses its validity. This is the motivation for construction of the unitary and analytic (U and A) models of studied form factors, that enable us to get the majority of our results. We use the U and A model to evaluate the contribution of the processes e + e - → Pγ, P = π 0 , η, η to the muon magnetic anomaly a μ in the lowest order of the hadronic vacuum polarization. For the contribution a μ had,LO (π + π - ) we demonstrate, that the use of the model leads to a dramatic error reduction with respect to the results of other authors. We also get a shift in the central value in the 'correct' direction, that brings the theoretical value closer to the experimental one. This results encourages us to use the model also for the evaluation of a μ had,LO (P γ ). These contributions are smaller, however the precision of the experiment makes their evaluation necessary. We further use the U and A model of the transition form factors of π 0 , η and η ' mesons to predict the partial decay widths of these particles Γ π 0 →γγ and Γ η→γγ and Γ η ' →γγ . In this way we make an independent cross check of the PDG table values. We find an agreement in the case of Γ η→γγ and Γ η ' →γγ , even a smaller uncertainty for Γ η ' →γγ . In the case of Γ π 0 →γγ we find a disagreement that points to an interesting problem. We wonder whether it
Measurement of the gamma gamma* -> pi0 transition form factor
Energy Technology Data Exchange (ETDEWEB)
Aubert, B.
2009-06-02
We study the reaction e{sup +}e{sup -} {yields} e{sup +}e{sup -}{pi}{sup 0} in the single tag mode and measure the differential cross section d{sigma}/dQ{sup 2} and the {gamma}{gamma}* {yields} {pi}{sup 0} transition form factor in the mometum transfer range from 4 to 40 GeV{sup 2}. At Q{sup 2} > 10 GeV{sup 2} the measured form factor exceeds the asymptotic limit predicted by perturbative QCD. The analysis is based on 442 fb{sup -1} of integrated luminosity collected at PEP-II with the BABAR detector at e{sup +}e{sup -} center-of-mass energies near 10.6 GeV.
SU(3) breaking in hyperon transition vector form factors
International Nuclear Information System (INIS)
Shanahan, P.E.; Thomas, A.W.; Young, R.D.; Zanotti, J.M.; Rakow, P.E.L.
2015-08-01
We present a calculation of the SU(3)-breaking corrections to the hyperon transition vector form factors to O(p 4 ) in heavy baryon chiral perturbation theory with finite-range regularisation. Both octet and decuplet degrees of freedom are included. We formulate a chiral expansion at the kinematic point Q 2 =-(M B 1 -M B 2 ) 2 , which can be conveniently accessed in lattice QCD. The two unknown low-energy constants at this point are constrained by lattice QCD simulation results for the Σ - →n and Ξ 0 →Σ + transition form factors. Hence we determine lattice-informed values of f 1 at the physical point. This work constitutes progress towards the precise determination of vertical stroke V us vertical stroke from hyperon semileptonic decays.
Coverlayer fabrication for small form factor optical disks
Kim, Jong-Hwan; Lee, Seung-Won; Kim, Jin-Hong
2004-09-01
Two different coverlayers made of UV resin and coversheet were prepared for small form factor optical disks. Thin coverlayer of 10 mm and thick coverlayer of 80 mm were fabricated for flying optical head and non-flying optical head, respectively. Thickness uniformity was analyzed for both coverlayers, and new designs to diminish a ski-jump phenomenon were suggested. Mechanical properties of protective film made of UV resin were investigated.
Generation of truncated recombinant form of tumor necrosis factor ...
African Journals Online (AJOL)
Purpose: To produce truncated recombinant form of tumor necrosis factor receptor 1 (TNFR1), cysteine-rich domain 2 (CRD2) and CRD3 regions of the receptor were generated using pET28a and E. coli/BL21. Methods: DNA coding sequence of CRD2 and CRD3 was cloned into pET28a vector and the corresponding ...
Meson Transition Form Factors in Light-Front Holographic QCD
Energy Technology Data Exchange (ETDEWEB)
Brodsky, Stanley J.; /SLAC; Cao, Fu-Guang; /Massey U.; de Teramond, Guy F.; /Costa Rica U.
2011-06-22
We study the photon-to-meson transition form factors (TFFs) F{sub M{gamma}}(Q{sup 2}) for {gamma}{gamma}* {yields} M using light-front holographic methods. The Chern-Simons action, which is a natural form in 5-dimensional anti-de Sitter (AdS) space, leads directly to an expression for the photon-to-pion TFF for a class of confining models. Remarkably, the predicted pion TFF is identical to the leading order QCD result where the distribution amplitude has asymptotic form. The Chern-Simons form is local in AdS space and is thus somewhat limited in its predictability. It only retains the q{bar q} component of the pion wavefunction, and further, it projects out only the asymptotic form of the meson distribution amplitude. It is found that in order to describe simultaneously the decay process {pi}{sup 0} {yields} {gamma}{gamma} and the pion TFF at the asymptotic limit, a probability for the q{bar q} component of the pion wavefunction P{sub q{bar q}} = 0.5 is required; thus giving indication that the contributions from higher Fock states in the pion light-front wavefunction need to be included in the analysis. The probability for the Fock state containing four quarks (anti-quarks) which follows from analyzing the hadron matrix elements, P{sub q{bar q}q{bar q}} {approx} 10%, agrees with the analysis of the pion elastic form factor using light-front holography including higher Fock components in the pion wavefunction. The results for the TFFs for the {eta} and {eta}{prime} mesons are also presented. The rapid growth of the pion TFF exhibited by the BABAR data at high Q{sup 2} is not compatible with the models discussed in this article, whereas the theoretical calculations are in agreement with the experimental data for the {eta} and {eta}{prime} TFFs.
Helicity non-conserving form factor of the proton
Energy Technology Data Exchange (ETDEWEB)
Voutier, E.; Furget, C.; Knox, S. [Universite Joseph Fourier, Grenoble (France)] [and others
1994-04-01
The study of the hadron structure in the high Q{sup 2} range contributes to the understanding of the mechanisms responsible for the confinement of quarks and gluons. Among the numerous experimental candidates sensitive to these mechanisms, the helicity non-conserving form factor of the proton is a privileged observable since it is controlled by non-perturbative effects. The authors investigate here the feasibility of high Q{sup 2} measurements of this form factor by means of the recoil polarization method in the context of the CEBAF 8 GeV facility. For that purpose, they discuss the development of a high energy proton polarimeter, based on the H({rvec p},pp) elastic scattering, to be placed at the focal plane of a new hadron spectrometer. It is shown that this experimental method significantly improves the knowledge of the helicity non-conserving form factor of the proton up to 10 GeV{sup 2}/c{sup 2}.
Pion transverse charge density from timelike form factor data
Energy Technology Data Exchange (ETDEWEB)
Gerald Miller, Mark Strikman, Christian Weiss
2011-01-01
The transverse charge density in the pion can be represented as a dispersion integral of the imaginary part of the pion form factor in the timelike region. This formulation incorporates information from e+e- annihilation experiments and allows one to reconstruct the transverse density much more accurately than from the spacelike pion form factor data alone. We calculate the transverse density using an empirical parametrization of the timelike pion form factor and estimate that it is determined to an accuracy of ~10% at a distance b ~ 0.1 fm, and significantly better at larger distances. The density is found to be close to that obtained from a zero-width rho meson pole over a wide range and shows a pronounced rise at small distances. The resulting two-dimensional image of the fast-moving pion can be interpreted in terms of its partonic structure in QCD. We argue that the singular behavior of the charge density at the center requires a substantial presence of pointlike configurations in the pion's partonic wave function, which can be probed in other high-momentum transfer processes.
Canouï-Poitrine, Florence; Poulain, Cécile; Molto, Anna; Le Thuaut, Aurélie; Lafon, Cécile; Farrenq, Valérie; Ferkal, Salah; Le Corvoisier, Philippe; Ghaleh, Bijan; Bastuji-Garin, Sylvie; Fautrel, B; Dougados, Maxime; Claudepierre, Pascal
2014-09-01
To determine the frequency of and factors associated with early tumor necrosis factor α (TNFα) antagonist therapy in everyday clinical practice in patients with suspected axial spondyloarthropathy (SpA). We used data from the prospective observational study in the French Devenir des Spondylarthropathies Indifférenciées Récentes (DESIR; Outcome of Recent Undifferentiated Spondylarthropathies) cohort of 708 patients with recent-onset (50 (OR 1.88, 95% CI 1.24-2.87, P = 0.003), current or past disease-modifying antirheumatic drug use (OR 2.09, 95% CI 1.22-3.59, P = 0.008), systemic corticosteroid use (OR 2.48, 95% CI 1.43-4.34, P = 0.002), and mild to severe radiographic hip abnormalities (OR 9.43, 95% CI 2.11-42.09, P = 0.003). After adjustment on these factors, Achilles enthesis hypervascularization by power Doppler and number of work days missed were associated with TNFα antagonist therapy. In the DESIR cohort, approximately one-fourth of patients with recent IBP suggestive of axial SpA were under anti-TNFα therapy after 1 year of followup. All factors associated with this early initiation reflected higher disease activity, refractoriness, or severity, which suggests compliance of French rheumatologists with current treatment guidelines. Copyright © 2014 by the American College of Rheumatology.
Relativistic form factors for clusters with nonrelativistic wave functions
International Nuclear Information System (INIS)
Mitra, A.N.; Kumari, I.
1977-01-01
Using a simple variant of an argument employed by Licht and Pagnamenta (LP) on the effect of Lorentz contraction on the elastic form factors of clusters with nonrelativistic wave functions, it is shown how their result can be generalized to inelastic form factors so as to produce (i) a symmetrical appearance of Lorentz contraction effects in the initial and final states, and (ii) asymptotic behavior in accord with dimensional scaling theories. A comparison of this result with a closely analogous parametric form obtained by Brodsky and Chertok from a propagator chain model leads, with plausible arguments, to the conclusion of an effective mass M for the cluster, with M 2 varying as the number n of the quark constituents, instead of as n 2 . A further generalization of the LP formula is obtained for an arbitrary duality-diagram vertex, again with asymptotic behavior in conformity with dimensional scaling. The practical usefulness of this approach is emphasized as a complementary tool to those of high-energy physics for phenomenological fits to data up to moderate values of q 2
Forms and factors of peer violence and victimisation
Directory of Open Access Journals (Sweden)
Dinić Bojana
2014-01-01
Full Text Available The main aim of this study was to explore the latent structure of violence and victimisation based on the factor analysis of the Peer Violence and Victimisation Questionnaire (PVVQ, as well as to examine the correlates of violence and victimisation. The sample included 649 secondary school students (61.8% male from the urban area. Besides the PVVQ, the Aggressiveness questionnaire AVDH was administered. Based on parallel analysis, three factors were extracted in the violence domain, as well as in the victimisation domain of the PVVQ. The factors were interpreted as a physical, verbal and relational form of violence and victimisation, which is in line with common classifications. The correlations of those forms with the aggressiveness dimensions were positive. The relationships with gender, school grade and school achievement referred to the importance of interaction effects between the mentioned characteristics of students and the tendency towards violence or being exposed to it. The main result is that boys from lower school grades and students with lower school achievement in general, are more prone to manifesting physical violence and more often are the target of physical violence. These groups of students are the target groups for preventive programs. The resulting effects indicated the complexity of the violence phenomenon and pointed to the need to consider the wider context of student’s characteristics in the determination of violence. [Projekat Ministarstva nauke Republike Srbije, br. 179037 i br. 179053
CEBAF at higher energies and the kaon electromagnetic form factor
Energy Technology Data Exchange (ETDEWEB)
Baker, O.K.
1994-04-01
The electromagnetic production of strangeness, the physics of exciting systems having strangeness degrees of freedom (production of hadrons with one or more strange constituent quarks) using electromagnetic probes (real or virtual photons), is one of the frontier areas of research which will be investigated at the Continuous Electron Beam Accelerator Facility (CEBAF) when it becomes operational. CEBAF is expected to have an important impact upon this field of research using its specialized set of detection instruments and high quality electron beam. This paper focusses upon one aspect of the associated production of strangeness - the determination of the kaon electromagnetic form factor at high squared momentum transfers.
Neutral pion form factor measurement by the NA62 experiment
Zamkovsky, Michal; Ambrosino, F.; Antonelli, A.; Anzivino, G.; Arcidiacono, R.; Baldini, W.; Balev, S.; Batley, J. R.; Behler, M.; Bifani, S.; Biino, C.; Bizzeti, A.; Blazek, T.; Bloch-Devaux, B.; Bocquet, G.; Bolotov, V.; Bucci, F.; Cabibbo, N.; Calvetti, M.; Cartiglia, N.; Ceccucci, A.; Cenci, P.; Cerri, C.; Cheshkov, C.; Chze, J. B.; Clemencic, M.; Collazuol, G.; Costantini, F.; Cotta Ramusino, A.; Coward, D.; Cundy, D.; Dabrowski, A.; DAgostini, G.; Dalpiaz, P.; Damiani, C.; Danielsson, H.; De Beer, M.; Dellacasa, G.; Derr, J.; Dibon, H.; Di Filippo, D.; DiLella, L.; Doble, N.; Duk, V.; Engelfried, J.; Eppard, K.; Falaleev, V.; Fantechi, R.; Fidecaro, M.; Fiorini, L.; Fiorini, M.; Fonseca Martin, T.; Frabetti, P. L.; Fucci, A.; Gallorini, S.; Gatignon, L.; Gersabeck, E.; Gianoli, A.; Giudici, S.; Gonidec, A.; Goudzovski, E.; Goy Lopez, S.; Gushchin, E.; Hallgren, B.; Hita-Hochgesand, M.; Holder, M.; Hristov, P.; Iacopini, E.; Imbergamo, E.; Jeitler, M.; Kalmus, G.; Kekelidze, V.; Kleinknecht, K.; Koval, M.; Kozhuharov, V.; Kubischta, W.; Kurshetsov, V.; Lamanna, G.; Lazzeroni, C.; Lenti, M.; Leonardi, E.; Litov, L.; Lurkin, N.; Madigozhin, D.; Maier, A.; Mannelli, I.; Marchetto, F.; Marel, G.; Markytan, M.; Marouelli, P.; Martini, M.; Masetti, L.; Massarotti, P.; Mazzucato, E.; Michetti, A.; Mikulec, I.; Misheva, M.; Molokanova, N.; Monnier, E.; Moosbrugger, U.; Morales Morales, C.; Moulson, M.; Movchan, S.; Munday, D. J.; Napolitano, M.; Nappi, A.; Neuhofer, G.; Norton, A.; Numao, T.; Obraztsov, V.; Palladino, V.; Patel, M.; Pepe, M.; Peters, A.; Petrucci, F.; Petrucci, M. C.; Peyaud, B.; Piandani, R.; Piccini, M.; Pierazzini, G.; Polenkevich, I.; Popov, I.; Potrebenikov, Y.; Raggi, M.; Renk, B.; Retire, F.; Riedler, P.; Romano, A.; Rubin, P.; Ruggiero, G.; Salamon, A.; Saracino, G.; Savri, M.; Scarpa, M.; Semenov, V.; Sergi, A.; Serra, M.; Shieh, M.; Shkarovskiy, S.; Slater, M. W.; Sozzi, M.; Spadaro, T.; Stoynev, S.; Swallow, E.; Szleper, M.; Valdata-Nappi, M.; Valente, P.; Vallage, B.; Velasco, M.; Veltri, M.; Venditti, S.; Wache, M.; Wahl, H.; Walker, A.; Wanke, R.; Widhalm, L.; Winhart, A.; Winston, R.; Wood, M. D.; Wotton, S. A.; Yushchenko, O.; Zinchenko, A.; Ziolkowski, M.
2017-07-01
The NA62 experiment at CERN collected a large sample of charged kaon decays with a highly efficient trigger for decays into electrons in 2007. The kaon beam represents a source of tagged neutral pion decays in vacuum. A measurement of the electromagnetic transition form factor slope of the neutral pion in the time-like region from ∼1 million fully reconstructed π 0 Dalitz decay is presented. The limits on dark photon production in π 0 decays from the earlier kaon experiment at CERN, NA48/2, are also reported.
Measurement of the π0 electromagnetic transition form factor slope
Lazzeroni, C.; Lurkin, N.; Romano, A.; Blazek, T.; Koval, M.; Ceccucci, A.; Danielsson, H.; Falaleev, V.; Gatignon, L.; Goy Lopez, S.; Hallgren, B.; Maier, A.; Peters, A.; Piccini, M.; Riedler, P.; Frabetti, P. L.; Gersabeck, E.; Kekelidze, V.; Madigozhin, D.; Misheva, M.; Molokanova, N.; Movchan, S.; Potrebenikov, Yu.; Shkarovskiy, S.; Zinchenko, A.; Rubin, P.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Fiorini, M.; Gianoli, A.; Norton, A.; Petrucci, F.; Savrié, M.; Wahl, H.; Bizzeti, A.; Bucci, F.; Iacopini, E.; Lenti, M.; Veltri, M.; Antonelli, A.; Moulson, M.; Raggi, M.; Spadaro, T.; Eppard, K.; Hita-Hochgesand, M.; Kleinknecht, K.; Renk, B.; Wanke, R.; Winhart, A.; Winston, R.; Bolotov, V.; Duk, V.; Gushchin, E.; Ambrosino, F.; Di Filippo, D.; Massarotti, P.; Napolitano, M.; Palladino, V.; Saracino, G.; Anzivino, G.; Imbergamo, E.; Piandani, R.; Sergi, A.; Cenci, P.; Pepe, M.; Costantini, F.; Doble, N.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Balev, S.; Collazuol, G.; DiLella, L.; Gallorini, S.; Goudzovski, E.; Lamanna, G.; Mannelli, I.; Ruggiero, G.; Cerri, C.; Fantechi, R.; Kholodenko, S.; Kurshetsov, V.; Obraztsov, V.; Semenov, V.; Yushchenko, O.; D'Agostini, G.; Leonardi, E.; Serra, M.; Valente, P.; Fucci, A.; Salamon, A.; Bloch-Devaux, B.; Peyaud, B.; Engelfried, J.; Coward, D.; Kozhuharov, V.; Litov, L.; Arcidiacono, R.; Bifani, S.; Biino, C.; Dellacasa, G.; Marchetto, F.; Numao, T.; Retière, F.; NA62 Collaboration
2017-05-01
The NA62 experiment collected a large sample of charged kaon decays in 2007 with a highly efficient trigger for decays into electrons. A measurement of the π0 electromagnetic transition form factor slope parameter from 1.11 ×106 fully reconstructed K± →π± πD0, πD0 →e+e- γ events is reported. The measured value a = (3.68 ± 0.57) ×10-2 is in good agreement with theoretical expectations and previous measurements, and represents the most precise experimental determination of the slope in the time-like momentum transfer region.
N to Delta electromagnetic transition form factors from Lattice QCD
Alexandrou, C; Lippert, T; Neff, H; Negele, J W; Schilling, K; Tsapalis, A; Forcrand, Ph. de; Lippert, Th.
2004-01-01
The magnetic dipole, the electric quadrupole and the Coulomb quadrupole amplitudes for the transition $\\gamma N\\to \\Delta$ are evaluated in lattice QCD. Unquenching effects are studied using two dynamical Wilson fermions. The dipole transition form factor is accurately determined at several values of momentum transfer. The electric quadrupole amplitude is found to be non-zero yielding a negative value for the ratio,$ R_{EM}$, of electric quadrupole to magnetic dipole amplitudes given in the chiral limit at three values of momenta transfer.
Nucleon electromagnetic form factors in twisted mass lattice QCD
International Nuclear Information System (INIS)
Alexandrou, C.; Jansen, K.; Korzec, T.; Humboldt Univ. Berlin
2011-02-01
We present results on the nucleon electromagnetic form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length L=2.1 fm and L=2.8 fm. Cut-off effects are investigated using three different values of the lattice spacings, namely a=0.089 fm, a=0.070 fm and a=0.056 fm. The nucleon magnetic moment, Dirac and Pauli radii are obtained in the continuum limit and chirally extrapolated to the physical pion mass allowing for a comparison with experiment. (orig.)
Two-nucleon transfer reactions with form factor models
International Nuclear Information System (INIS)
Osman, A.
1980-04-01
The theory of two-nucleon transfer reactions is considered. Nuclear reactions are considered with triton or 3 He particles which are used as projectiles in stripping reactions and as detected particles in pick-up reactions. In each channel we have a four-particle problem, three of them are nucleons and the fourth is a heavy particle. These transfer reactions are studied on the basis of the generaled R-matrix method. Different channel functions of the sub-clusters in the triton and 3 He particles are included. Model form factors are obtained and are used in two-nucleon transfer reactions. Differential cross-sections of different two-nucleon transfer reactions are calculated and are found in good agreement with the experimental data. The correct normalization and spectroscopic factors are obtained. (author)
Measurement of the $\\Lambda_{b}^{0}$ Decay Form Factor
Abdallah, J; Adam, W; Adzic, P; Albrecht, T; Alderweireld, T; Alemany-Fernandez, R; Allmendinger, T; Allport, P P; Amaldi, Ugo; Amapane, N; Amato, S; Anashkin, E; Andreazza, A; Andringa, S; Anjos, N; Antilogus, P; Apel, W D; Arnoud, Y; Ask, S; Åsman, B; Augustin, J E; Augustinus, A; Baillon, Paul; Ballestrero, A; Bambade, P; Barbier, R; Bardin, Dimitri Yuri; Barker, G; Baroncelli, A; Battaglia, Marco; Baubillier, M; Becks, K H; Begalli, M; Behrmann, A; Ben-Haim, E; Benekos, N C; Benvenuti, Alberto C; Bérat, C; Berggren, M; Berntzon, L; Bertrand, D; Besançon, M; Besson, N; Bloch, D; Blom, M; Bluj, M; Bonesini, M; Boonekamp, M; Booth, P S L; Borisov, G; Botner, O; Bouquet, B; Bowcock, T J V; Boyko, I; Bracko, M; Brenner, R; Brodet, E; Brückman, P; Brunet, J M; Bugge, L; Buschmann, P; Calvi, M; Camporesi, T; Canale, V; Carena, F; Castro, N; Cavallo, F R; Chapkin, M M; Charpentier, P; Checchia, P; Chierici, R; Shlyapnikov, P; Chudoba, J; Chung, S U; Cieslik, K; Collins, P; Contri, R; Cosme, G; Cossutti, F; Costa, M J; Crawley, B; Crennell, D J; Cuevas-Maestro, J; D'Hondt, J; Dalmau, J; Da Silva, T; Da Silva, W; Della Ricca, G; De Angelis, A; de Boer, Wim; De Clercq, C; De Lotto, B; De Maria, N; De Min, A; De Paula, L S; Di Ciaccio, Lucia; Di Simone, A; Doroba, K; Drees, J; Dris, M; Eigen, G; Ekelöf, T J C; Ellert, M; Elsing, M; Espirito-Santo, M C; Fanourakis, G K; Fassouliotis, D; Feindt, M; Fernández, J; Ferrer, A; Ferro, F; Flagmeyer, U; Föth, H; Fokitis, E; Fulda-Quenzer, F; Fuster, J A; Gandelman, M; García, C; Gavillet, P; Gazis, E N; Gokieli, R; Golob, B; Gómez-Ceballos, G; Gonçalves, P; Graziani, E; Grosdidier, G; Grzelak, K; Guy, J; Haag, C; Hallgren, A; Hamacher, K; Hamilton, K; Haug, S; Hauler, F; Hedberg, V; Hennecke, M; Herr, H; Hoffman, J; Holmgren, S O; Holt, P J; Houlden, M A; Hultqvist, K; Jackson, J N; Jarlskog, G; Jarry, P; Jeans, D; Johansson, E K; Johansson, P D; Jonsson, P; Joram, C; Jungermann, L; Kapusta, F; Katsanevas, S; Katsoufis, E C; Kernel, G; Kersevan, Borut P; Kerzel, U; Kiiskinen, A P; King, B T; Kjaer, N J; Kluit, P; Kokkinias, P; Kourkoumelis, C; Kuznetsov, O; Krumshtein, Z; Kucharczyk, M; Lamsa, J; Leder, G; Ledroit, F; Leinonen, L; Leitner, R; Lemonne, J; Lepeltier, V; Lesiak, T; Liebig, W; Liko, D; Lipniacka, A; Lopes, J H; López, J M; Loukas, D; Lutz, P; Lyons, L; MacNaughton, J; Malek, A; Maltezos, S; Mandl, F; Marco, J; Marco, R; Maréchal, B; Margoni, M; Marin, J C; Mariotti, C; Markou, A; Martínez-Rivero, C; Masik, J; Mastroyiannopoulos, N; Matorras, F; Matteuzzi, C; Mazzucato, F; Mazzucato, M; McNulty, R; Meroni, C; Meyer, W T; Myagkov, A; Migliore, E; Mitaroff, W A; Mjörnmark, U; Moa, T; Moch, M; Mönig, K; Monge, R; Montenegro, J; Moraes, D; Moreno, S; Morettini, P; Müller, U; Münich, K; Mulders, M; Mundim, L M; Murray, W; Muryn, B; Myatt, Gerald; Myklebust, T; Nassiakou, M; Navarria, Francesco Luigi; Nawrocki, K; Nicolaidou, R; Nikolenko, M; Oblakowska-Mucha, A; Obraztsov, V F; Olshevskii, A G; Onofre, A; Orava, Risto; Österberg, K; Ouraou, A; Oyanguren, A; Paganoni, M; Paiano, S; Palacios, J P; Palka, H; Papadopoulou, T D; Pape, L; Parkes, C; Parodi, F; Parzefall, U; Passeri, A; Passon, O; Peralta, L; Perepelitsa, V F; Perrotta, A; Petrolini, A; Piedra, J; Pieri, L; Pierre, F; Pimenta, M; Piotto, E; Podobnik, T; Poireau, V; Pol, M E; Polok, G; Poropat, P; Pozdnyakov, V; Pukhaeva, N; Pullia, Antonio; Rames, J; Ramler, L; Read, A; Rebecchi, P; Rehn, J; Reid, D; Reinhardt, R; Renton, P B; Richard, F; Rídky, J; Rivero, M; Rodríguez, D; Romero, A; Ronchese, P; Rosenberg, E I; Roudeau, Patrick; Rovelli, T; Ruhlmann-Kleider, V; Ryabtchikov, D; Sadovskii, A; Salmi, L; Salt, J; Savoy-Navarro, A; Schwickerath, U; Segar, A; Sekulin, R L; Siebel, M; Sissakian, A N; Smadja, G; Smirnova, O G; Sokolov, A; Sopczak, A; Sosnowski, R; Spassoff, Tz; Stanitzki, M; Stocchi, A; Strauss, J; Stugu, B; Szczekowski, M; Szeptycka, M; Szumlak, T; Tabarelli de Fatis, T; Taffard, A C; Tegenfeldt, F; Timmermans, J; Tkatchev, L G; Tobin, M; Todorovova, S; Tomé, B; Tonazzo, A; Tortosa, P; Travnicek, P; Treille, D; Tristram, G; Trochimczuk, M; Troncon, C; Turluer, M L; Tyapkin, I A; Tyapkin, P; Tzamarias, S; Uvarov, V; Valenti, G; van Dam, P; Van Eldik, J; Van Lysebetten, A; Van Remortel, N; Van Vulpen, I B; Vegni, G; Veloso, F; Venus, W A; Verdier, P; Verzi, V; Vilanova, D; Vitale, L; Vrba, V; Wahlen, H; Washbrook, A J; Weiser, C; Wicke, D; Wickens, J H; Wilkinson, G; Winter, M; Witek, M; Yushchenko, O P; Zalewska-Bak, A; Zalewski, Piotr; Zavrtanik, D; Zhuravlov, V; Zimin, N I; Zinchenko, A I; Zupan, M
2004-01-01
The form factor of Lambda_b^0 baryons is estimated using 3.46 10^6 hadronic Z decays collected by the DELPHI experiment between 1992 and 1995. Charmed Lambda_c^+ baryons fully reconstructed in the pK-pi+, pK0_S, and Lambda pi+pi+pi- modes, are associated to a lepton with opposite charge in order to select Lambda_b^0 -> Lambda_c^+ l^- anti-nu_l decays. From a combined likelihood and event rate fit to the distribution of the Isgur-Wise variable w, and using the Heavy Quark Effective Theory (HQET), the slope of the b-baryon form factor is measured to be: rho-hat^2 = 2.03 +/- 0.46 (stat) ^{+0.72}_{-1.00} (syst). The exclusive semileptonic branching fraction Br(Lambda_b^0 -> Lambda_c^+ l^- anti-nu_l) can be derived from rho-hat^2 and is found to be (5.0^{+1.1}_{-0.8} (stat) ^{+1.6}_{-1.2} (syst))%. Limits on other branching fractions are also obtained.
Energy Technology Data Exchange (ETDEWEB)
Miceli, Tia [New Mexico State U.; Papavassiliou, Vassili [New Mexico State U.; Pate, Stephen [New Mexico State U.; Woodruff, Katherine [New Mexico State U.
2015-11-01
The MicroBooNE neutrino experiment at Fermilab is constructing a liquid-argon time-projection chamber for the Booster Neutrino Beam to study neutrino oscillations and interactions with nucleons and nuclei, starting in 2014. We describe the experiment and focus on its unique abilities to measure cross sections at low values of $Q^2$. In particular, the neutral-current elastic scattering cross section is especially interesting, as it is sensitive to the contribution of the strange sea quark spin to the angular-momentum of the nucleon, $\\Delta s$. Implications for dark-matter searches are discussed.
International Nuclear Information System (INIS)
Egli, S.; Engfer, R.; Grab, C.; Hermes, E.A.; Pruys, H.S.; Schaaf, A. van der; Vermeulen, D.
1986-01-01
The radiative pion decay π + ->e + νe + e - has been observed for the first time. Information on the form factors was obtained from the kinematical distribution of 79 events. The vector form factor has the same sign as the pion decay constant fsub(π). The ratios of axial-vector form factors to the vector form factor are γ=Fsub(A)/Fsub(V)=0.7+-0.5 and xi=R/Fsub(V)=2.3+-0.6. The value for γ is in agreement with the small positive value (0.53+-0.06) and excludes the large negative value (-2.49+-0.06) of γ obtained in π + ->e + νγ experiments. (orig.)
Meson Form Factors and Deep Exclusive Meson Production Experiments
Energy Technology Data Exchange (ETDEWEB)
Horn, Tanja [The Catholic Univ. of America, Washington, DC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2017-05-01
Pion and kaon electroproduction data play a unique role in Nature and our understanding of them is essential for explaining hadron structure. Precision longitudinaltransverse separated pion and kaon cross sections are of particular interest. They allow for the extraction of meson form factors and validation of understanding of hard exclusive and semi-inclusive reactions (π+, K+, π0, γ) towards 3D hadron imaging and potential future flavor decomposition. We review recent data and present prospects for deep exclusive pion and kaon electroproduction at the 12 GeV Jefferson Lab including the prospects to use projected charged- and neutral pion data to further determine the spin, charge-parity and flavor of GPDs, including the helicity-flip GPDs.
Inelastic form factor of the He-4 (0{sup +})-resonance
Energy Technology Data Exchange (ETDEWEB)
Kegel, Simon [Institut fuer Kernphysik, Universitaet Mainz (Germany)
2016-07-01
Electron scattering experiments offer a great opportunity to probe nuclear properties and to get deeper insight into nuclear dynamics, because the electromagnetic interaction is well understood. The MAMI electron accelerator at Mainz, Germany, can reach high beam intensities with electron energies in the range up to 1.5 GeV, thus it is a powerful tool to investigate nuclear dynamics with high statistics and precision. In 2009 an electron scattering experiment was performed by the A1 collaboration at MAMI with the focus on the study of inclusive reactions of light nuclei. The goal of the experiment is to test effective field theories, including phenomenological 3- or 4-body forces in potentials for ab-initio calculations. In the talk a new analysis of the form factor for the He-4 (0{sup +})-resonance is presented.
Near-field recording for small form factor optical disks
Kim, Jin-Hong
2007-02-01
Small form factor optical disk (SFFOD) with a diameter of 27.4mm was prepared for a mobile application. Near-field recording (NFR) technology with a flying optical head is applied to SFFOD for high density and small volume. A problem of contamination was observed at the head-disk interface(HDI) for first-surface recording. As a solution of the problem, a cover-layer was laminated onto the disk to move the focal plane into the media, which could solve the contamination problem. An edge bead free cover-layer could be coated with UVcurable resin by using an outer-ring technique during the spin coating process. A diamond-like carbon(DLC) film and a lubricant film were coated on the disk to reduce the HDI problems.
Pion form factor in QCD at intermediate momentum transfers
Braun, V. M.; Khodjamirian, A.; Maul, M.
2000-04-01
We present a quantitative analysis of the electromagnetic pion form factor in the light-cone sum rule approach, including radiative corrections and higher-twist effects. The comparison to the existing data favors the asymptotic profile of the pion distribution amplitude and allows us to estimate the deviation: [∫du/uφπ(u)]/[∫du/uφasπ(u)]=1.1+/-0.1 at the scale of 1 GeV. Special attention is paid to the precise definition and interplay of soft and hard contributions at intermediate momentum transfer, and to the matching of the sum rule to the perturbative QCD prediction. We observe a strong numerical cancellation between the soft (end-point) contribution and power-suppressed hard contributions of higher twist, so that the total nonperturbative correction to the usual PQCD result turns out to be of the order of 30% for Q2~1 GeV2.
Conformal anomaly of generalized form factors and finite loop integrals
Chicherin, Dmitry
2017-01-01
We reveal a new mechanism of conformal symmetry breaking at Born level. It occurs in generalized form factors with several local operators and an on-shell state of massless particles. The effect is due to hidden singularities on collinear configurations of the momenta. This conformal anomaly is different from the holomorphic anomaly of amplitudes. We present a number of examples in four and six dimensions. We find an application of the new conformal anomaly to finite loop momentum integrals with one or more massless legs. The collinear region around a massless leg creates a contact anomaly, made visible by the loop integration. The anomalous conformal Ward identity for an $\\ell-$loop integral is a 2nd-order differential equation whose right-hand side is an $(\\ell-1)-$loop integral. We show several examples, in particular the four-dimensional scalar double box.
Five-meson VDM fits to the nucleon form factors
International Nuclear Information System (INIS)
Mehrotra, S.; Roos, M.
1975-01-01
Nucleon electromagnetic form factor data in the spacelike and the timelike regions are fitted with a VDM sum of (up to five) isovector and isoscalar pole terms. Finite width effects are included in the rho and the rhosup(,) terms. The effects of including the rhosup(,) and the psi(3105) are studied. Good fits are found only when the rhosup(,) is allowed to have a too low mass (1.2-1.4 GeV) and when in addition some of the couplings or other derived quantities disagree with other estimates. It is concluded that VDM is unable to describe the data unless one introduces a number of yet unknown mesons, such as ωsup(,), phisup(,), rhosup(,)(1.2), etc. (author)
Baryon Transition Form Factors at JLab: Status and Outlook
Energy Technology Data Exchange (ETDEWEB)
Ralf Gothe
2009-12-01
The measurements of exclusive single-meson and double-pion electro-production cross sections off the proton to study nucleon resonances will be extended to higher momentum transfers with the CLAS12 detector and the energy upgraded CEBAF beam. Based on new theoretical developments to extract and interpret the electromagnetic transition form factors and on the experience gained from the most recent results, the newly formed collaboration of experimentalists and theorists shall enable us to provide unprecedented high-precision data, high-quality analyses, and state-of-the-art model and QCD based calculations in a Q domain up to 10 GeV{sup 2}. For the first time nucleon resonance structures will be studied at still unexplored distance scales, where the dressed quark contributions are the dominating degrees of freedom and their strong interaction is responsible for the ground and excited nucleon state formation. These studies also open up a promising opportunity to understand the origin of more than 98% of the nucleon mass that is created by strong fields predominantly at these distance scales by dressing the current quarks.
Compton backscattering axial spectrometer
International Nuclear Information System (INIS)
Rad'ko, V.E.; Mokrushin, A.D.; Razumovskaya, I.V.
1981-01-01
Compton gamma backscattering axial spectrometer of new design with the 200 time larger aperture as compared with the known spectrometers at the equal angular resolution (at E=159 keV) is described. Collimator unit, radiation source and gamma detector are located in the central part of the spectrometer. The investigated specimen (of cylindrical form) and the so called ''black body'' used for absorption of photons, passed through the specimen are placed in the peripheric part. Both these parts have an imaginary symmetry axis that is why the spectrometer is called axial. 57 Co is used as the gamma source. The 122 keV spectral line which corresponds to the 83 keV backscattered photon serves as working line. Germanium disk detector of 10 mm diameter and 4 mm height has energy resolution not worse than 900 eV. The analysis of results of test measurements of compton water profile and their comparison with data obtained earlier show that only finity of detector resolution can essentially affect the form of Compton profile. It is concluded that the suggested variant of the spectrometer would be useful for determination of Compton profiles of chemical compounds of heavy elements [ru
Chen, Kan; Pang, Cheng-Qun; Liu, Xiang; Matsuki, Takayuki
2015-04-01
Inspired by the abundant experimental observation of axial-vector states, we study whether the observed axial-vector states can be categorized into the conventional axial-vector meson family. In this paper we carry out an analysis based on the mass spectra and two-body Okubo-Zweig-Iizuka-allowed decays. Besides testing the possible axial-vector meson assignments, we also predict abundant information for their decays and the properties of some missing axial-vector mesons, which are valuable for further experimental exploration of the observed and predicted axial-vector mesons.
Moltó, Anna; Granger, Benjamin; Wendling, Daniel; Breban, Maxime; Dougados, Maxime; Gossec, Laure
2015-09-01
To evaluate the effect of tumor necrosis factor (TNF) inhibitors on nonsteroidal antiinflammatory drug (NSAID) intake in a cohort of patients with early axial spondyloarthritis (SpA) over the first 2 years of followup. The Devenir des Spondylarthropathies Indifférenciées Récentes (DESIR) cohort is a prospective, multicenter, observational study cohort of patients with early inflammatory back pain. The management and treatment of these patients were decided by their treating rheumatologists. Data regarding NSAID intake (yes/no) and the Assessment of SpondyloArthritis international Society NSAID score were collected at each visit over 2 years of followup. Patients receiving a TNF inhibitor were matched with those receiving usual care, based on a propensity score. The NSAID-sparing effect of TNF inhibitors was estimated by comparing the percentage of patients reaching several end points (e.g., a decrease in the NSAID score to 50% or to <10 or in whom NSAID treatment was discontinued was greater in the TNF inhibitor group (67.6% versus 46.2%). Treatment with TNF inhibitors was associated with a decrease in the proportion of patients taking NSAIDs and with a rapid and sustained decrease in NSAID intake. This study is the first to confirm the NSAID-sparing effect of TNF inhibitors in patients with early axial SpA in a real-life clinical setting. © 2015, American College of Rheumatology.
Directory of Open Access Journals (Sweden)
Nicolae APOSTOLESCU
2013-03-01
Full Text Available This work describes a computer application to calculate the values of the factors which are used to determine the tensile rupture load of a lug under axial, transverse or oblique loading. It can be used as a procedure for identifying potential failure modes. Lugs are connector-type elements widely used as structural supports for pin connections in aerospace industry. Failure modes in lugs are functions of lug geometry and material mechanical properties. For a lug under axial load three modes of lug failure are considered: tension, shear and bearing. Under transverse load the load to cause rupture or unacceptable permanent deformation of the lug is given. Tension mode failure usually occurs in materials of low ductility. In materials with high ductility, the failure mode of a lug can be either tensile or shear tear-out, depending on the lug geometry. The application has a graphical interface that allows the user to use them with much ease and view immediately the results and provides a flexible ad-hoc print reports and diagrams that allow to present analysis information. It includes Microsoft Excel Object Library as reference to the Excel material properties file.
Nucleon form factors and hidden symmetry in holographic QCD
International Nuclear Information System (INIS)
Hong, D.K.; Rho, M.; Yee, H.-U.; Yi, P.
2007-10-01
The vector dominance of the electromagnetic (EM) form factors both for mesons and baryons arises naturally in holographic QCD, where both the number of colors and the 't Hooft coupling are taken to be very large, offering a bona-fide derivation of the notion of vector dominance. The crucial ingredient for this is the infinite tower of vector mesons in the approximations made which share features that are characteristic of the quenched approximation in lattice QCD. We approximate the infinite sum by contributions from the lowest four vector mesons of the tower which turn out to saturate the charge and magnetic moment sum rules within a few % and compute them totally free of unknown parameters for momentum transfers Q 2 approx.= 1 GeV 2 . We identify certain observables that can be reliably computed within the approximations and others that are not, and discuss how the improvement of the latter can enable one to bring holographic QCD closer to QCD proper. (author)
Measurements of the nucleon form factors at large momentum transfers
International Nuclear Information System (INIS)
Andivahis, L.; Bosted, P.; Lung, A.; Arnold, R.; Keppel, C.; Rock, S.; Spengos, M.; Szalata, Z.; Tao, L.; Stuart, L.; Dietrich, F.; Alster, J.; Lichtenstadt, J.; Chang, C.; Dodge, W.; Gearhart, R.; Kuhn, S.; Gomez, J.; Griffioen, K.; Hicks, R.; Miskimen, R.; Peterson, G.; Rokni, S.; Hyde-Wright, C.; Swartz, K.; Petratos, G.; Sakumoto, W.
1992-12-01
New measurements of the electric G E (Q 2 ) and magnetic G M (Q 2 ) form factors of the nucleons are reported. The proton data cover the Q 2 range from 1.75 to 8.83 (GeV/c) 2 and the neutron data from 1.75 to 4.00 (GeV/c) 2 , more than doubling the range of previous data. Scaled by the dipole fit, G D (Q 2 ), the results for G Mp (Q 2 )/μ p G D (Q 2 ) decrease smoothly from 1.05 to 0.92, while G Ep (Q 2 )/G D (Q 2 ) is consistent with unity. The preliminary results for Gm.(Q2)1 GD(Q2) consistent with unity, while F En 2 is consistent with zero at all values of Q 2 . Comparisons are made to QCD Sum Rule, diquark, constituent quark, and VMD models, none of which agree with all of the new data
Dressed Quark Mass Dependence of Pion and Kaon Form Factors
Energy Technology Data Exchange (ETDEWEB)
Ninomiya, Y.; Bentz, W.; Cloet, I. C.
2015-02-04
The structure of hadrons is described well by the Nambu-Jona-Lasinio (NJL) model, which is a chiral effective quark theory of QCD. In this work we explore the electromagnetic structure of the pion and kaon using the three-flavor NJL model in the proper-time regularization scheme, including effects of the pion cloud at the quark level. In the calculation there is only one free parameter, which we take as the dressed light quark (u and d) mass. In the regime where the dressed light quark mass is approximately 0.25 GeV we find that the calculated values of the kaon decay constant, current quark masses, and quark condensates are consistent with experiment- and QCD-based analyses. We also investigate the dressed light quark mass dependence of the pion and kaon electromagnetic form factors, where comparison with empirical data and QCD predictions also favors a dressed light quark mass near 0.25 GeV.
Form factors in the beta decay; Factores de forma en la desintegracion Beta
Energy Technology Data Exchange (ETDEWEB)
Grau Carles, A.; Grau Malonda, A.
2007-07-01
Beta-decay was one of the nuclear physics fields more active in the last century. This book has a didactic objective: to actualize some basic concepts related with form factors in beta-decay. Some accepted points before 1957 are not valid today due to the non conservation of parity and the full acceptation of V-A interaction in beta-decay. To compute theoretically beta-decay observables one has to relate the form factors to transition matrix elements. The form factors are expressed in terms of nuclear matrix elements when some approximations are made. We assume that the nucleon inside the nucleus interact with leptons in the same way as free punctual electrons do. Consequently, the Dirac equation of a free particle is assumed. We compute the shape form factors for several forbidden transitions. A very important part of the book is the 106 examples, fully developed, which clarify the ideas and motivate one to know the different computation methods used in beta-decay and others nuclear and atomic fields. (Author) 50 refs.
Cytokinin response factors regulate PIN-FORMED auxin transporters
Czech Academy of Sciences Publication Activity Database
Šimášková, M.; O'Brien, J.A.; Khan, M.; Van Noorden, G.; Ötvös, K.; Vieten, A.; De Clercq, E.; Van Haperen, J.M.A.; Cuesta, C.; Hoyerová, Klára; Vanneste, S.; Marhavý, P.; Wabnik, K.; Van Breusegem, F.; Nowack, M.; Murphy, A.; Friml, J.; Weijers, D.; Beeckman, T.; Benková, E.
2015-01-01
Roč. 6, NOV (2015), s. 8717 ISSN 2041-1723 Institutional support: RVO:61389030 Keywords : ARABIDOPSIS -THALIANA * ROOT-MERISTEM * TRANSCRIPTION FACTORS Subject RIV: ED - Physiology Impact factor: 11.329, year: 2015
Radial and axial compression of pure electron
International Nuclear Information System (INIS)
Park, Y.; Soga, Y.; Mihara, Y.; Takeda, M.; Kamada, K.
2013-01-01
Experimental studies are carried out on compression of the density distribution of a pure electron plasma confined in a Malmberg-Penning Trap in Kanazawa University. More than six times increase of the on-axis density is observed under application of an external rotating electric field that couples to low-order Trivelpiece-Gould modes. Axial compression of the density distribution with the axial length of a factor of two is achieved by controlling the confining potential at both ends of the plasma. Substantial increase of the axial kinetic energy is observed during the axial compression. (author)
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
Axial model in curved space-time
Energy Technology Data Exchange (ETDEWEB)
Barcelos-Neto, J.; Farina, C.; Vaidya, A.N.
1986-12-11
We study the axial model in a background gravitational field. Using the zeta-function regularization, we obtain explicitly the anomalous divergence of the axial-vector current and the exact generating functional of the theory. We show that, as a consequence of a space-time-dependent metric, all differential equations involved in the theory generalize to their covariantized forms. We also comment on the finite-mass renormalization exhibited by the pseudoscalar field and the form of the fermion propagator.
Kim, Hyungsae
2010-10-05
Dof proteins are transcription factors that have a conserved single zinc finger DNA-binding domain. In this study, we isolated an activation tagging mutant Dof5.1-D exhibiting an upward-curling leaf phenotype due to enhanced expression of the REV gene that is required for establishing adaxialabaxial polarity. Dof5.1-D plants also had reduced transcript levels for IAA6 and IAA19 genes, indicating an altered auxin biosynthesis in Dof5.1-D. An electrophoretic mobility shift assay using the Dof5.1 DNA-binding motif and the REV promoter region indicated that the DNA-binding domain of Dof5.1 binds to a TAAAGT motif located in the 5′-distal promoter region of the REV promoter. Further, transient and chromatin immunoprecipitation assays verified binding activity of the Dof5.1 DNA-binding motif with the REV promoter. Consistent with binding assays, constitutive over-expression of the Dof5.1 DNA-binding domain in wild-type plants caused a downward-curling phenotype, whereas crossing Dof5.1-D to a rev mutant reverted the upward-curling phenotype of the Dof5.1-D mutant leaf to the wild-type. These results suggest that the Dof5.1 protein directly binds to the REV promoter and thereby regulates adaxialabaxial polarity. © 2010 Blackwell Publishing Ltd.
Recruitment of bloom-forming cyanobacteria and its driving factors
African Journals Online (AJOL)
STORAGESEVER
2008-12-29
Dec 29, 2008 ... Based on most of the literature, this paper reviewed the progress made in following aspects: cognition to cyanobacteria recruitment, various traps for studying cyanobacteria recruitment in lakes, recruitment patterns of some species of cyanobacteria, and the driving factors for recruitment. Additionally,.
Recruitment of bloom-forming cyanobacteria and its driving factors ...
African Journals Online (AJOL)
Based on most of the literature, this paper reviewed the progress made in following aspects: cognition to cyanobacteria recruitment, various traps for studying cyanobacteria recruitment in lakes, recruitment patterns of some species of cyanobacteria, and the driving factors for recruitment. Additionally, perspective studies of ...
FACTORS OF ECOLOGICAL STATE FORMING FOR URBANIZED ENVIRONMENT
Directory of Open Access Journals (Sweden)
Г. Франчук
2012-04-01
Full Text Available Impact of enterprises for exploitation and repair of aviation techniques on soil state in zone of airport hasbeen investigated. Technical and ecological characteristic of an airport located within city territory has beendone. Monitoring of soils on territories near aviaenterprises has been carried out. The most important factorsfor soil toxicity has been determined. Assessment of summary effect of these factors has been done
Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations
Energy Technology Data Exchange (ETDEWEB)
Wagner, J.C.; DeHart, M.D.
2000-03-01
This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ``end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified.
Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations
International Nuclear Information System (INIS)
Wagner, J.C.; DeHart, M.D.
2000-01-01
This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ''end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified
Resource Form Factor and Installation of GFA Controllers
Energy Technology Data Exchange (ETDEWEB)
DeSteese, John G.; Hammerstrom, Donald J.
2009-11-15
The focus of this task is to optimize the form and placement of a controller comprising the Grid Friendly™ appliance (GFA) controller, power supply and power relay (and/or a solid-state power electronic switch) that would command a domestic water heater to shed its load in response to stress on the electric power grid. The GFA controller would disconnect the water heater from its supply circuit whenever it senses a low voltage signal or other indicators of system stress communicated via the electric power distribution system. Power would be reconnected to the appliance when the GFA controller senses the absence of these signals. This project has also considered more frequent cycling of this controller’s relay switch to perform demand-side frequency regulation. The principal criteria considered in this optimization are reliability, cost and life expectancy of the GFA components. The alternative embodiments of the GFA equipment under consideration are: Option 1- installation inside the insulation space of the water heater between the tank and jacket Option 2 containment in a separate nearby electrical enclosure Option 3 - as a modification or adjunct to the distribution panel housing and/or the breaker that protects the water heater supply circuit.
Notari, Alessio
2016-12-22
We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term $\\frac{\\phi}{f_\\gamma} F \\tilde{F}$, such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density $\\rho_R$, which which can lead to inflation without the need of a flat potential. We analyze the system, for momenta $k$ smaller than the cutoff $f_\\gamma$, including numerically the backreaction. We consider the evolution from a given static initial condition and explicitly show that, if $f_\\gamma$ is smaller than the field excursion $\\phi_0$ by about a factor of at least ${\\cal O} (20)$, there is a friction effect which turns on before that the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of...
E M form factors of the nucleon in a chiral model with momentum projection
International Nuclear Information System (INIS)
Drago, A.; Tambini, U.; Fiolhais, M.
1997-01-01
The chiral chromo dielectric model with a quadratic potential for the confining field is used to compute electromagnetic form factors of the nucleon. A variational approach based on the hedgehog Ansatz and on angular momentum-isospin and linear momentum projection formalism is applied to describe the nucleon. The form factors are computed using momentum eigenstates, therefore taking into account recoil effects. With the exception of the magnetic form factor of the proton, the others are well reproduced. (author)
Study of baryon octet charge form factors in perturbative chiral quark model
International Nuclear Information System (INIS)
Liu, X.Y.; Khosonthongkee, K.; Limphirat, A.; Yan, Y.
2014-01-01
The charge form factors of baryon octet are studied in the perturbative chiral quark model (PCQM). The relativistic quark wave function is extracted by fitting the theoretical results of the nucleon charge form factors to the experimental data and the predetermined quark wave function is applied to study the charge form factors of other octet baryons. The PCQM results are found, based on the predetermined quark wave function, in good agreement with the experimental data. (author)
On soft theorems and form factors in N=4 SYM theory
Energy Technology Data Exchange (ETDEWEB)
Bork, L.V. [Institute for Theoretical and Experimental Physics,Moscow (Russian Federation); The Center of Fundamental and Applied Research,Moscow (Russian Federation); Onishchenko, A.I. [Moscow Institute of Physics and Technology (State University),Dolgoprudny (Russian Federation); Skobeltsyn Institute of Nuclear Physics, Moscow State University,Moscow (Russian Federation)
2015-12-04
Soft theorems for the form factors of 1/2-BPS and Konishi operator supermultiplets are derived at tree level in N=4 SYM theory. They have a form identical to the one in the amplitude case. For MHV sectors of stress tensor and Konishi operator supermultiplets loop corrections to soft theorems are considered at one loop level. They also appear to have universal form in the soft limit. Possible generalization of the on-shell diagrams to the form factors based on leading soft behavior is suggested. Finally, we give some comments on inverse soft limit and integrability of form factors in the limit q{sup 2}→0.
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
Singh, B.; Erni, W.; Krusche, B.; Steinacher, M.; Walford, N.; Liu, B.; Liu, H.; Liu, Z.; Shen, X.; Wang, C.; Zhao, J.; Albrecht, M.; Erlen, T.; Fink, M.; Heinsius, F.; Held, T.; Holtmann, T.; Jasper, S.; Keshk, I.; Koch, H.; Kopf, B.; Kuhlmann, M.; Kuemmel, M.; Leiber, S.; Mikirtychyants, M.; Musiol, P.; Mustafa, A.; Pelizaeus, M.; Pychy, J.; Richter, M.; Schnier, C.; Schroeder, T.; Sowa, C.; Steinke, M.; Triffterer, T.; Wiedner, U.; Ball, M.; Beck, R.; Hammann, C.; Ketzer, B.; Kube, M.; Mahlberg, P.; Rossbach, M.; Schmidt, C.; Schmitz, R.; Thoma, U.; Urban, M.; Walther, D.; Wendel, C.; Wilson, A.; Bianconi, A.; Bragadireanu, M.; Caprini, M.; Pantea, D.; Patel, B.; Czyzycki, W.; Domagala, M.; Filo, G.; Jaworowski, J.; Krawczyk, M.; Lisowski, F.; Lisowski, E.; Michalek, M.; Poznanski, P.; Plazek, J.; Korcyl, K.; Kozela, A.; Kulessa, P.; Lebiedowicz, P.; Pysz, K.; Schafer, W.; Szczurek, A.; Fiutowski, T.; Idzik, M.; Mindur, B.; Przyborowski, D.; Swientek, K.; Biernat, J.; Kamys, B.; Kistryn, S.; Korcyl, G.; Krzemien, W.; Magiera, A.; Moskal, P.; Pyszniak, A.; Rudy, Z.; Salabura, P.; Smyrski, J.; Strzempek, P.; Wronska, A.; Augustin, I.; Bohm, R.; Lehmann, I.; Marinescu, D. Nicmorus; Schmitt, L.; Varentsov, V.; Al-Turany, M.; Belias, A.; Deppe, H.; Dzhygadlo, R.; Ehret, A.; Flemming, H.; Gerhardt, A.; Goetzen, K.; Gromliuk, A.; Gruber, L.; Karabowicz, R.; Kliemt, R.; Krebs, M.; Kurilla, U.; Lehmann, D.; Loechner, S.; Luehning, J.; Lynen, U.; Orth, H.; Patsyuk, M.; Peters, K.; Saito, T.; Schepers, G.; Schmidt, C. J.; Schwarz, C.; Schwiening, J.; Taeschner, A.; Traxler, M.; Ugur, C.; Voss, B.; Wieczorek, P.; Wilms, A.; Zuehlsdorf, M.; Abazov, V.; Alexeev, G.; Arefiev, V. A.; Astakhov, V.; Barabanov, M. Yu.; Batyunya, B. V.; Davydov, Y.; Dodokhov, V. Kh.; Efremov, A.; Fechtchenko, A.; Fedunov, A. G.; Galoyan, A.; Grigoryan, S.; Koshurnikov, E. K.; Lobanov, Y. Yu.; Lobanov, V. I.; Makarov, A. F.; Malinina, L. V.; Malyshev, V.; Olshevskiy, A. G.; Perevalova, E.; Piskun, A. A.; Pocheptsov, T.; Pontecorvo, G.; Rodionov, V.; Rogov, Y.; Salmin, R.; Samartsev, A.; Sapozhnikov, M. G.; Shabratova, G.; Skachkov, N. B.; Skachkova, A. N.; Strokovsky, E. A.; Suleimanov, M.; Teshev, R.; Tokmenin, V.; Uzhinsky, V.; Vodopianov, A.; Zaporozhets, S. A.; Zhuravlev, N. I.; Zorin, A. G.; Branford, D.; Glazier, D.; Watts, D.; Boehm, M.; Britting, A.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Dobbs, S.; Seth, K.; Tomaradze, A.; Xiao, T.; Bettoni, D.; Carassiti, V.; Ramusino, A. Cotta; Dalpiaz, P.; Drago, A.; Fioravanti, E.; Garzia, I.; Savrie, M.; Akishina, V.; Kisel, I.; Kozlov, G.; Pugach, M.; Zyzak, M.; Gianotti, P.; Guaraldo, C.; Lucherini, V.; Bersani, A.; Bracco, G.; Macri, M.; Parodi, R. F.; Biguenko, K.; Brinkmann, K.; Di Pietro, V.; Diehl, S.; Dormenev, V.; Drexler, P.; Dueren, M.; Etzelmueller, E.; Galuska, M.; Gutz, E.; Hahn, C.; Hayrapetyan, A.; Kesselkaul, M.; Kuehn, W.; Kuske, T.; Lange, J. S.; Liang, Y.; Metag, V.; Nanova, M.; Nazarenko, S.; Novotny, R.; Quagli, T.; Reiter, S.; Rieke, J.; Rosenbaum, C.; Schmidt, M.; Schnell, R.; Stenzel, H.; Thoering, U.; Ullrich, M.; Wagner, M. N.; Wasem, T.; Wohlfahrt, B.; Zaunick, H.; Ireland, D.; Rosner, G.; Seitz, B.; Deepak, P. N.; Kulkarni, A.; Apostolou, A.; Babai, M.; Kavatsyuk, M.; Lemmens, P. J.; Lindemulder, M.; Loehner, H.; Messchendorp, J.; Schakel, P.; Smit, H.; Tiemens, M.; van der Weele, J. C.; Veenstra, R.; Vejdani, S.; Dutta, K.; Kalita, K.; Kumar, A.; Roy, A.; Sohlbach, H.; Bai, M.; Bianchi, L.; Buescher, M.; Cao, L.; Cebulla, A.; Dosdall, R.; Gillitzer, A.; Goldenbaum, F.; Grunwald, D.; Herten, A.; Hu, Q.; Kemmerling, G.; Kleines, H.; Lehrach, A.; Nellen, R.; Ohm, H.; Orfanitski, S.; Prasuhn, D.; Prencipe, E.; Puetz, J.; Ritman, J.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Sterzenbach, G.; Stockmanns, T.; Wintz, P.; Wuestner, P.; Xu, H.; Zambanini, A.; Li, S.; Li, Z.; Sun, Z.; Xu, H.; Rigato, V.; Isaksson, L.; Achenbach, P.; Corell, O.; Denig, A.; Distler, M.; Hoek, M.; Karavdina, A.; Lauth, W.; Liu, Z.; Merkel, H.; Mueller, U.; Pochodzalla, J.; Sanchez, S.; Schlimme, S.; Sfienti, C.; Thiel, M.; Ahmadi, H.; Ahmed, S.; Bleser, S.; Capozza, L.; Cardinali, M.; Dbeyssi, A.; Deiseroth, M.; Feldbauer, F.; Fritsch, M.; Froehlich, B.; Jasinski, P.; Kang, D.; Khaneft, D.; Klasen, R.; Leithoff, H. H.; Lin, D.; Maas, F.; Maldaner, S.; Martinez, M.; Michel, M.; Espi, M. C. Mora; Morales, C. Morales; Motzko, C.; Nerling, F.; Noll, O.; Pflueger, S.; Pitka, A.; Pineiro, D. Rodriguez; Sanchez-Lorente, A.; Steinen, M.; Valente, R.; Weber, T.; Zambrana, M.; Zimmermann, I.; Fedorov, A.; Korjik, M.; Missevitch, O.; Boukharov, A.; Malyshev, O.; Marishev, I.; Balanutsa, V.; Balanutsa, P.; Chernetsky, V.; Demekhin, A.; Dolgolenko, A.; Fedorets, P.; Gerasimov, A.; Goryachev, V.; Chandratre, V.; Datar, V.; Dutta, D.; Jha, V.; Kumawat, H.; Mohanty, A. K.; Parmar, A.; Roy, B.; Sonika, G.; Fritzsch, C.; Grieser, S.; Hergemoeller, A.; Hetz, B.; Huesken, N.; Khoukaz, A.; Wessels, J. P.; Khosonthongkee, K.; Kobdaj, C.; Limphirat, A.; Srisawad, P.; Yan, Y.; Barnyakov, M.; Barnyakov, A. Yu.; Beloborodov, K.; Blinov, A. E.; Blinov, V. E.; Bobrovnikov, V. S.; Kononov, S.; Kravchenko, E. A.; Kuyanov, I. A.; Martin, K.; Onuchin, A. P.; Serednyakov, S.; Sokolov, A.; Tikhonov, Y.; Atomssa, E.; Kunne, R.; Marchand, D.; Ramstein, B.; van de Wiele, J.; Wang, Y.; Boca, G.; Costanza, S.; Genova, P.; Montagna, P.; Rotondi, A.; Abramov, V.; Belikov, N.; Bukreeva, S.; Davidenko, A.; Derevschikov, A.; Goncharenko, Y.; Grishin, V.; Kachanov, V.; Kormilitsin, V.; Levin, A.; Melnik, Y.; Minaev, N.; Mochalov, V.; Morozov, D.; Nogach, L.; Poslavskiy, S.; Ryazantsev, A.; Ryzhikov, S.; Semenov, P.; Shein, I.; Uzunian, A.; Vasiliev, A.; Yakutin, A.; Tomasi-Gustafsson, E.; Roy, U.; Yabsley, B.; Belostotski, S.; Gavrilov, G.; Izotov, A.; Manaenkov, S.; Miklukho, O.; Veretennikov, D.; Zhdanov, A.; Makonyi, K.; Preston, M.; Tegner, P.; Wolbing, D.; Back, T.; Cederwall, B.; Rai, A. K.; Godre, S.; Calvo, D.; Coli, S.; De Remigis, P.; Filippi, A.; Giraudo, G.; Lusso, S.; Mazza, G.; Mignone, M.; Rivetti, A.; Wheadon, R.; Balestra, F.; Iazzi, F.; Introzzi, R.; Lavagno, A.; Olave, J.; Amoroso, A.; Bussa, M. P.; Busso, L.; De Mori, F.; Destefanis, M.; Fava, L.; Ferrero, L.; Greco, M.; Hu, J.; Lavezzi, L.; Maggiora, M.; Maniscalco, G.; Marcello, S.; Sosio, S.; Spataro, S.; Birsa, R.; Bradamante, F.; Bressan, A.; Martin, A.; Calen, H.; Andersson, W. Ikegami; Johansson, T.; Kupsc, A.; Marciniewski, P.; Papenbrock, M.; Pettersson, J.; Schonning, K.; Wolke, M.; Galnander, B.; Diaz, J.; Chackara, V. Pothodi; Chlopik, A.; Kesik, G.; Melnychuk, D.; Slowinski, B.; Trzcinski, A.; Wojciechowski, M.; Wronka, S.; Zwieglinski, B.; Buehler, P.; Marton, J.; Steinschaden, D.; Suzuki, K.; Widmann, E.; Zmeskal, J.
2016-01-01
Simulation results for future measurements of electromagnetic proton form factors at PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel (p) over barp -> e(+)e(-) is studied
QCD sum rule calculation of the Isgur-Wise form factor
International Nuclear Information System (INIS)
Radyushkin, A.V.
1991-01-01
Within the QCD sum rule approach, we develop a formalism that enables one to calculate the form factors of the heavy-light mesons in the m Q → ∞ limit. It is shown that the behavior of the universal Isgur-Wise form factor is determined by the quark propagation function in imaginary time. (orig.)
Future Measurements of the Nucleon Elastic Electromagnetic Form Factors at Jefferson Lab
Gilfoyle, Gerard
2018-01-01
The elastic, electromagnetic form factors are fundamental observables that describe the internal structure of protons, neutrons, and atomic nuclei. Jefferson Lab in the United States has completed the 12 GeV Upgrade that will open new opportunities to study the form factors. A campaign to measure all four nucleon form factors (electric and magnetic ones for both proton and neutron) has been approved consisting of seven experiments in Halls A, B, and C. The increased energy of the electron beam will extend the range of precision measurements to higher Q2 for all four form factors together. This combination of measurements will allow for the decomposition of the results into their quark components and guide the development of a QCD-based understanding of nuclei in the non-perturbative regime. I will present more details on the 12 GeV Upgrade, the methods used to measure the form factors, and what we may learn.
Future Measurements of the Nucleon Elastic Electromagnetic Form Factors at Jefferson Lab
Directory of Open Access Journals (Sweden)
Gilfoyle Gerard
2018-01-01
Full Text Available The elastic, electromagnetic form factors are fundamental observables that describe the internal structure of protons, neutrons, and atomic nuclei. Jefferson Lab in the United States has completed the 12 GeV Upgrade that will open new opportunities to study the form factors. A campaign to measure all four nucleon form factors (electric and magnetic ones for both proton and neutron has been approved consisting of seven experiments in Halls A, B, and C. The increased energy of the electron beam will extend the range of precision measurements to higher Q2 for all four form factors together. This combination of measurements will allow for the decomposition of the results into their quark components and guide the development of a QCD-based understanding of nuclei in the non-perturbative regime. I will present more details on the 12 GeV Upgrade, the methods used to measure the form factors, and what we may learn.
On super form factors of half-BPS operators in =4 super Yang-Mills
Penante, Brenda; Spence, Bill; Travaglini, Gabriele; Wen, Congkao
2014-04-01
We compute form factors of half-BPS operators in = 4 super Yang-Mills dual to massive Kaluza-Klein modes in supergravity. These are appropriate supersymmetrisations of the scalar operators Tr ( ϕ k ) for any k, which for k = 2 give the chiral part of the stress-tensor multiplet operator. Using harmonic superspace, we derive simple Ward identities for these form factors, which we then compute perturbatively at tree level and one loop. We propose a novel on-shell recursion relation which links form factors with different numbers of fields. Using this, we conjecture a general formula for the n-point MHV form factors of for arbitrary k and n. Finally, we use supersymmetric generalised unitarity to derive compact expressions for all one-loop MHV form factors of in terms of one-loop triangles and finite two-mass easy box functions.
Remarks on electromagnetic form factors of hadrons in the quark model
International Nuclear Information System (INIS)
Vainshtein, A.I.; Zakharov, V.I.
1977-01-01
Relations between the transversal and longitudinal parts of elastic and quasielastic form factors are studied within the quark model. It is shown that for an even number of the constituent quarks the longitudinal part dominates while for an odd number the transversal part is the largest one. Consequences form this result are considered for deuteron form factor and for matrix elements of the electromagnetic transitions between π, rho, A 1 mesons
2016-12-01
Air Force Officer Qualifying Test, Form T1 AFOQT T2 Air Force Officer Qualifying Test, Form T2 AGFI Adjusted Goodness of Fit Index AI Air Force...Qualifying Test Electrical Maze subtest g General mental ability factor GFI Goodness of Fit Index GLS Generalized Least Squares GS Air Force...AFRL-RH-WP-TR-2016-0093 AIR FORCE OFFICER QUALIFYING TEST FORM T: INITIAL ITEM-, TEST-, FACTOR-, AND COMPOSITE-LEVEL ANALYSES
The scalar and electromagnetic form factors of the nucleon in dispersively improved Chiral EFT
Energy Technology Data Exchange (ETDEWEB)
Alarcon, Jose Manuel [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2018-04-01
We present a method for calculating the nucleon form factors of G-parity-even operators. This method combines chiral effective field theory (χEFT) and dispersion theory. Through unitarity we factorize the imaginary part of the form factors into a perturbative part, calculable with χEFT, and a non-perturbative part, obtained through other methods. We consider the scalar and electromagnetic (EM) form factors of the nucleon. The results show an important improvement compared to standard chiral calculations, and can be used in analysis of the low-energy properties of the nucleon.
The off-shell electromagnetic form factors of pions and kaons in chiral perturbation theory
International Nuclear Information System (INIS)
Rudy, T.E.; Fearing, H.W.; Scherer, S.
1994-01-01
The off-shell electromagnetic vertex of a (pseudo-) scalar particle contains, in general, two form factors F and G which depend, in addition to the squared momentum transfer, on the invariant masses associated with the initial and final legs of the vertex. Chiral perturbation theory to one loop is used to calculate the off-shell form factors of pions and kaons. The formalism of Gasser and Leutwyler, which was previously used to calculate the on-shell limit of the form factor F, is extended to accommodate the most general form for off-shell Green's functions in the pseudoscalar meson sector. We find that chiral symmetry predicts that the form factors F of the charged pions and kaons go off-shell in the same way, i.e., the off-shell slope at the real photon point is given by the same new phenomenological constant β 1 . Furthermore, it is shown that at order p 4 the form factor F of the K 0 does not show any off-shell dependence. The form factors G are all related to the form factors F in the correct fashion as required by the Ward-Takahashi identity. Numerical results for different off-shell kinematics are presented. (author). 34 refs., 10 figs
Off-shell electromagnetic form factors of pions and kaons in chiral perturbation theory
International Nuclear Information System (INIS)
Rudy, T.E.; Fearing, H.W.; Scherer, S.
1994-01-01
The off-shell electromagnetic vertex of a (pseudo)scalar particle contains, in general, two form factors F and G which depend, in addition to the squared momentum transfer, on the invariant masses associated with the initial and final legs of the vertex. Chiral perturbation theory to one loop is used to calculate the off-shell form factors of pions and kaons. The formalism of Gasser and Leutwyler, which was previously used to calculate the on-shell limit of the form factor F, is extended to accommodate the most general form for off-shell Green's functions in the pseudoscalar meson sector. We find that chiral symmetry predicts that the form factors F of the charged pions and kaons go off-shell in the same way, i.e., the off-shell slope at the real photon point is given by the same new phenomenological constant β 1 . Furthermore, it is shown that at order p 4 the form factor F of the K 0 does not show any off-shell dependence. The form factors G are all related to the form factors F in the correct fashion as required by the Ward-Takahashi identity. Numerical results for different off-shell kinematics are presented
Ward, Thomas
2013-10-01
A new electromagnetic neutral-current quark mixing matrix, analog to the well-known Cabibbo-Kobayashi-Maskawa (CKM) weak charge-current matrix, is proposed to account for the strange quark content of the neutron and proton and part of the anomalous axial vector magnetic moments. The EM-CKM matrix is shown to be equivalent to the weak-CKM matrix following an EM to weak gauge symmetry transformation, demonstrating the universality of the Standard Model (SM) CKM quark mixing matrix. The electric and magnetic form factors are reformulated using a new QCD three quark nucleon gyromagnetic factor, Dirac and Pauli form factors and anomalous kappa factors. The old 1943 Jauch form factors which have been systematically used and developed for many years is shown to be in stark disagreement with the new global set of experimental polarized electron-proton scattering data whereas the reformulated SM parameter set of this study is shown to agree very well, lending strong support for this new EM SM approach.
The neutron electric form factor to Q² = 1.45 (GeV/c)²
Energy Technology Data Exchange (ETDEWEB)
Plaster, Bradley [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
2004-02-01
The nucleon elastic electromagnetic form factors are fundamental quantities needed for an understanding of nucleon and nuclear electromagnetic structure. The evolution of the Sachs electric and magnetic form factors with Q^{2}, the square of the four-momentum transfer, is related to the distribution of charge and magnetization within the nucleon. High precision measurements of the nucleon form factors are essential for stringent tests of our current theoretical understanding of confinement within the nucleon. Measurements of the neutron form factors, in particular, those of the neutron electric form factor, have been notoriously difficult due to the lack of a free neutron target and the vanishing integral charge of the neutron. Indeed, a precise measurement of the neutron electric form factor has eluded experimentalists for decades; however, with the advent of high duty-factor polarized electron beam facilities, experiments employing polarization degrees of freedom have finally yielded the first precise measurements of this fundamental quantity. Following a general overview of the experimental and theoretical status of the nucleon form factors, a detailed description of an experiment designed to extract the neutron electric form factor from measurements of the neutron's recoil polarization in quasielastic 2H(e, e')1H scattering is presented. The experiment described here employed the Thomas Jefferson National Accelerator Facility's longitudinally polarized electron beam, a magnetic spectrometer for detection of the scattered electron, and a neutron polarimeter designed specifically for this experiment. Measurements were conducted at three Q^{2} values of 0.45, 1.13, and 1.45 (GeV/c)^{2}, and the final results extracted from an analysis of the data acquired in this experiment are reported and compared with recent theoretical predictions for the nucleon form factors.
Nucleon electromagnetic form factors using lattice simulations at the physical point
Energy Technology Data Exchange (ETDEWEB)
Alexandrou, C. [The Cyprus Institute, Nicosia (Cyprus). Computation-based Science and Technology Research Center; Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Constantinou, M. [Temple Univ., Philadelphia, PA (United States). Dept. of Physics; Hadjiyiannakou, K.; Kallidonis, C.; Koutsou, G. [The Cyprus Institute, Nicosia (Cyprus). Computation-based Science and Technology Research Center; Jansen, K. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Vaquero Aviles-Casco, A. [Utah Univ., Salt Lake City, UT (United States). Dept. of Physics and Astronomy
2017-09-20
We present results for the nucleon electromagnetic form factors using an ensemble of maximally twisted mass clover-improved fermions with pion mass of about 130 MeV. We use multiple sink-source separations and three analysis methods to probe ground-state dominance. We evaluate both the connected and disconnected contributions to the nucleon matrix elements. We find that the disconnected quark loop contributions to the isoscalar matrix elements are small giving an upper bound of up to 2% of the connected and smaller than its statistical error. We present results for the isovector and isoscalar electric and magnetic Sachs form factors and the corresponding proton and neutron form factors. By fitting the momentum dependence of the form factors to a dipole form or to the z-expansion we extract the nucleon electric and magnetic radii, as well as, the magnetic moment. We compare our results to experiment as well as to other recent lattice QCD calculations.
A Factor Analytic Study of the Coopersmith Self-Esteem Inventory Adult Short Form.
Haines, Janet; Wilson, George V.
1988-01-01
A factor analysis was conducted on the Coopersmith Self-Esteem Inventory-Adult Short Form using 237 college students and 43 female office workers in Australia. Factors were found corresponding with three of the four subscales: general self, social self-peers, and home-parents (family). No factor related to the school-academic (work) subscale. (SLD)
On-shell diagrams, Graßmannians and integrability for form factors
Energy Technology Data Exchange (ETDEWEB)
Frassek, Rouven [Department of Mathematical Sciences, Durham University,South Road, Durham DH1 3LE (United Kingdom); Meidinger, David; Nandan, Dhritiman; Wilhelm, Matthias [Institut für Mathematik und Institut für Physik, Humboldt-Universität zu Berlin,IRIS Gebäude, Zum Großen Windkanal 6, 12489 Berlin (Germany)
2016-01-29
We apply on-shell and integrability methods that have been developed in the context of scattering amplitudes in N=4 SYM theory to tree-level form factors of this theory. Focussing on the colour-ordered super form factors of the chiral part of the stress-tensor multiplet as an example, we show how to systematically construct on-shell diagrams for these form factors with the minimal form factor as further building block in addition to the three-point amplitudes. Moreover, we obtain analytic representations in terms of Graßmannian integrals in spinor helicity, twistor and momentum twistor variables. While Yangian invariance is broken by the operator insertion, we find that the form factors are eigenstates of the integrable spin-chain transfer matrix built from the monodromy matrix that yields the Yangian generators. Constructing them via the method of R operators allows to introduce deformations that preserve the integrable structure. We finally show that the integrable properties extend to minimal tree-level form factors of generic composite operators as well as certain leading singularities of their n-point loop-level form factors.
An experimental survey of the factors that affect leaching from low-level radioactive waste forms
International Nuclear Information System (INIS)
Dougherty, D.R.; Pietrzak, R.F.; Fuhrmann, M.; Colombo, P.
1988-09-01
This report represents the results of an experimental survey of the factors that affect leaching from several types of solidified low-level radioactive waste forms. The goal of these investigations was to determine those factors that accelerate leaching without changing its mechanism(s). Typically, although not in every case,the accelerating factors include: increased temperature, increased waste loading (i.e., increased waste to binder ratio), and decreased size (i.e., decreased waste form volume to surface area ratio). Additional factors that were studied were: increased leachant volume to waste form surface area ratio, pH, leachant composition (groundwaters, natural and synthetic chelating agents), leachant flow rate or replacement frequency and waste form porosity and surface condition. Other potential factors, including the radiation environment and pressure, were omitted based on a survey of the literature. 82 refs., 236 figs., 13 tabs
An experimental survey of the factors that affect leaching from low-level radioactive waste forms
Energy Technology Data Exchange (ETDEWEB)
Dougherty, D.R.; Pietrzak, R.F.; Fuhrmann, M.; Colombo, P.
1988-09-01
This report represents the results of an experimental survey of the factors that affect leaching from several types of solidified low-level radioactive waste forms. The goal of these investigations was to determine those factors that accelerate leaching without changing its mechanism(s). Typically, although not in every case,the accelerating factors include: increased temperature, increased waste loading (i.e., increased waste to binder ratio), and decreased size (i.e., decreased waste form volume to surface area ratio). Additional factors that were studied were: increased leachant volume to waste form surface area ratio, pH, leachant composition (groundwaters, natural and synthetic chelating agents), leachant flow rate or replacement frequency and waste form porosity and surface condition. Other potential factors, including the radiation environment and pressure, were omitted based on a survey of the literature. 82 refs., 236 figs., 13 tabs.
A measurement of the space-like pion electromagnetic form factor
International Nuclear Information System (INIS)
Amendolia, S.R.; Badelek, B.; Batignani, G.; Bedeschi, F.; Bertolucci, E.; Bettoni, D.; Bosisio, L.; Bradaschia, C.; Dell'Orso, M.; Fidecaro, F.; Foa, L.; Focardi, E.; Giazotto, A.; Giorgi, M.A.; Marrocchesi, P.S.; Menzione, A.; Ristori, L.; Scribano, A.; Tonelli, G.; Triggiani, G.; Codino, A.; Enorini, M.; Fabbri, F.L.; Laurelli, P.; Satta, L.; Spillantini, P.; Zallo, A.
1986-01-01
The pion form factor has been measured in the space-like q 2 region 0.014 to 0.26 (GeV/c) 2 by scattering 300 GeV pions from the electrons of a liquid hydrogen target. A detailed description is given of the apparatus, data analysis and corrections to the data. The mean square charge radius extracted from the data is model-dependent. We find that a form which includes a realistic description of the form factor phase gives a similar result to the naive pole form, and conclude π 2 >=0.439±0.008 fm 2 . (orig.)
International Nuclear Information System (INIS)
Theussl, L.; Noguera, S.; Amghar, A.; Desplanques, B.
2003-01-01
The effect of different boost expressions, pertinent to the instant, front and point forms of relativistic quantum mechanics, is considered for the calculation of the ground-state form factor of a two-body system in simple scalar models. Results with a Galilean boost as well as an explicitly covariant calculation based on the Bethe-Salpeter approach are given for comparison. It is found that the present so-called point-form calculations of form factors strongly deviate from all the other ones. This suggests that the formalism which underlies them requires further elaboration. A proposition in this sense is made. (author)
Measurement of the form factor in the decay K+ → π0e+vsub(e)
International Nuclear Information System (INIS)
Martyn, H.U.
1974-01-01
Following an introduction into the theory of the K(l3) decay, the fundamentals for the measuring methods of the form factor are derived. The choice of the quantity of nuclear events, the problems of the detection probabilities and of the background, and the form factor analysis are dealt with in detail. The analysis shows that the form factor can be very well described by a linear parametrization. The upper limits for scalar and tensorial interaction contributions are given; these results confirm the validity of the V-A theory also for strangeness-changing decays. (BJ/LH) [de
Grassmannians and form factors with q{sup 2}=0 in N=4 SYM theory
Energy Technology Data Exchange (ETDEWEB)
Bork, L.V. [Institute for Theoretical and Experimental Physics,Moscow (Russian Federation); The Center for Fundamental and Applied Research, All-Russia Research Institute of Automatics,Moscow (Russian Federation); Onishchenko, A.I. [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research,Dubna (Russian Federation); Moscow Institute of Physics and Technology (State University),Dolgoprudny (Russian Federation); Skobeltsyn Institute of Nuclear Physics, Moscow State University,Moscow (Russian Federation)
2016-12-16
In this paper we consider tree level form factors of operators from stress tensor operator supermultiplet with light-like operator momentum q{sup 2}=0. We present a conjecture for the Grassmannian integral representation both for these tree level form factors as well as for leading singularities of their loop counterparts. The presented conjecture was successfully checked by reproducing several known answers in MHV and N{sup k−2}MHV, k≥3 sectors together with appropriate soft limits. We also discuss the cancellation of spurious poles and relations between different BCFW representations for such form factors on simple examples.
High harmonic generation from axial chiral molecules.
Wang, Dian; Zhu, Xiaosong; Liu, Xi; Li, Liang; Zhang, Xiaofan; Lan, Pengfei; Lu, Peixiang
2017-09-18
Axial chiral molecules, whose stereogenic element is an axis rather than a chiral center, have attracted widespread interest due to their important application, such as asymmetric synthesis and chirality transfer. We investigate high harmonic generation from axial chiral molecules with bichromatic counterrotating circularly polarized laser fields. High harmonic generation from three typical molecules: (Sa)-3-chloropropa-1,2-dien-1-ol, propadiene, and (Ra)-2,3-pentadiene is simulated with time-dependent density-functional theory and strong field approximation. We found that harmonic spectra for 3D oriented axial chiral molecules exhibit obvious circular dichroism. However, the circular dichroism of High harmonic generation from an achiral molecule is much trivial. Moreover, the dichroism of high harmonic generation still exists when axial chiral molecules are 1D oriented,such as (Sa) -3-chloropropa-1,2-dien-1-ol. For a special form of axial chiral molecules with the formula abC=C=Cab (a, b are different substituents), like (Ra)-2,3-pentadiene, the dichroism discriminations disappear when the molecules are only in 1D orientation. The circular dichroism of high harmonic generation from axial chiral molecules is well explained by the trajectory analysis based on the semiclassical three-step mechanism.
DEFF Research Database (Denmark)
Pedersen, Susanne Juhl; Sørensen, Inge Juul; Lambert, Robert G. W.
2011-01-01
metalloproteinase 3 [MMP-3], and cartilage oligomeric matrix protein [COMP]), and bone turnover (CTX-I and osteocalcin) to inflammation on magnetic resonance imaging (MRI) and radiographic progression in patients with axial spondylarthritis (SpA) beginning tumor necrosis factor α (TNFα) inhibitor therapy.......To investigate the relationship of circulating biomarkers of inflammation (C-reactive protein [CRP], interleukin-6 [IL-6], and YKL-40), angiogenesis (vascular endothelial growth factor), cartilage turnover (C-terminal crosslinking telopeptide of type II collagen [CTX-II], total aggrecan, matrix...
DEFF Research Database (Denmark)
Pedersen, Susanne Juhl; Sørensen, Inge Juul; Lambert, Robert G W
2011-01-01
metalloproteinase 3 [MMP-3], and cartilage oligomeric matrix protein [COMP]), and bone turnover (CTX-I and osteocalcin) to inflammation on magnetic resonance imaging (MRI) and radiographic progression in patients with axial spondylarthritis (SpA) beginning tumor necrosis factor a (TNFa) inhibitor therapy.......To investigate the relationship of circulating biomarkers of inflammation (C-reactive protein [CRP], interleukin-6 [IL-6], and YKL-40), angiogenesis (vascular endothelial growth factor), cartilage turnover (C-terminal crosslinking telopeptide of type II collagen [CTX-II], total aggrecan, matrix...
Form factors and wave functions in covariant light-cone dynamics
International Nuclear Information System (INIS)
Leitner, O.
2002-01-01
Full text: Meson wave functions and transition form factors are investigated in a covariant light front formalism. We focus on the pseudo-scalar and vector particles. We develop the theoretical approach and apply it to determine B, D, π, K, J/ψ, r and ω wave functions. In our study, the relativistic structure is fully expressed. For the phenomenological approach, physical constraints such as the decay constant, transition form factor, electromagnetic form factor and charge radius are used. As regards transitions, we analyse exclusive semi-leptonic B and D decays. We study precisely the transitions 0 - → 0 - and 0 - → 1 - . Wave functions extracted previously in our analysis are taken into account in order to calculate decay form factors
Electric form factors of the octet baryons from lattice QCD and chiral extrapolation
International Nuclear Information System (INIS)
Shanahan, P.E.; Thomas, A.W.; Young, R.D.; Zanotti, J.M.; Pleiter, D.; Stueben, H.
2014-03-01
We apply a formalism inspired by heavy baryon chiral perturbation theory with finite-range regularization to dynamical 2+1-flavor CSSM/QCDSF/UKQCD Collaboration lattice QCD simulation results for the electric form factors of the octet baryons. The electric form factor of each octet baryon is extrapolated to the physical pseudoscalar masses, after finite-volume corrections have been applied, at six fixed values of Q 2 in the range 0.2-1.3 GeV 2 . The extrapolated lattice results accurately reproduce the experimental form factors of the nucleon at the physical point, indicating that omitted disconnected quark loop contributions are small. Furthermore, using the results of a recent lattice study of the magnetic form factors, we determine the ratio μ p G E p /G M p . This quantity decreases with Q 2 in a way qualitatively consistent with recent experimental results.
Up- and down-quark contributions to the nucleon form factors
International Nuclear Information System (INIS)
Qattan, I.A.; Arrington, J.
2014-01-01
Recent measurements of the neutron's electric to magnetic form factors ratio, R n = μ n G E n /G M n , up to 3.4 (GeV/c) 2 combined with existing R p = μ-pG E p /G M p measurements in the same Q 2 range allowed, for the first time, a separation of the up- and down- quark contributions to the form factors at high Q 2 , as presented by Cates, et al.. Our analysis expands on the original work by including additional form factor data, applying two-photon exchange (TPE) corrections, and accounting for the uncertainties associated with all of the form factor measurements. (authors)
The antiferromagnetic form factor of La2NiO4
International Nuclear Information System (INIS)
Wang, X.L.; Stassis, C.; Johnston, D.C.; Leung, T.C.; Ye, J.; Harmon, B.N.; Lander, G.H.; Schultz, A.J.; Loong, C.; Honig, J.M.
1991-01-01
Neutron-diffraction techniques have been used to study the antiferromagnetic form factor of a La 2 NiO 4 single crystal at 15 K. The antiferromagnetic form factor was obtained by measuring the integrated intensities of 16 magnetic reflections. A plateau is clearly seen at low Q (up to 3 A -1 ) in the experimentally determined form factor, similar to those observed for La 2 CuO 4 and Sr 2 CuO 2 Cl 2 . As in the case of these latter compounds, the fit of the experimental data by a Ni 2+ ionic form factor is not satisfactory. The experimental data are compared with a recent spin-polarized band calculation and with a covalency model
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
Measurement of the energy dependence of the form factor $f_{+}$ in $K^{0}_{e3}$ decay
Apostolakis, Alcibiades J; Backenstoss, Gerhard; Bargassa, P; Behnke, O; Benelli, A; Bertin, V; Blanc, F; Bloch, P; Carlson, P J; Carroll, M; Cawley, E; Chertok, M B; Danielsson, M; Dejardin, M; Derré, J; Ealet, A; Eleftheriadis, C; Fetscher, W; Fidecaro, Maria; Filipcic, A; Francis, D; Fry, J; Gabathuler, Erwin; Gamet, R; Gerber, H J; Go, A; Haselden, A; Hayman, P J; Henry-Coüannier, F; Hollander, R W; Jon-And, K; Kettle, P R; Kokkas, P; Kreuger, R; Le Gac, R; Leimgruber, F; Mandic, I; Manthos, N; Marel, Gérard; Mikuz, M; Miller, J; Montanet, François; Müller, A; Nakada, Tatsuya; Pagels, B; Papadopoulos, I M; Pavlopoulos, P; Polivka, G; Rickenbach, R; Roberts, B L; Ruf, T; Schäfer, M; Schaller, L A; Schietinger, T; Schopper, A; Tauscher, Ludwig; Thibault, C; Touchard, F; Touramanis, C; van Eijk, C W E; Vlachos, S; Weber, P; Wigger, O; Wolter, M; Zavrtanik, D; Zimmerman, D
2000-01-01
Neutral-kaon decays to \\pielnu\\ % recorded by the CPLEAR experimentwere analysed to determine the $q^2$ dependence of the \\Kzet\\ electroweak form factor $f_+$. Based on $365\\,612$ events,this form factor was found to have a linear dependence on $q^2$with a slope $\\lambda_+ = 0.0245 \\pm 0.0012_{\\text{stat}} \\pm 0.0022_{\\text{syst}}$.
Forms, Factors and Efficiency of Eco-management in Bulgarian Farms with High Eco-activity
Bachev, Hrabrin
2014-01-01
This paper presents the results of a first large-scale study on forms, factors, and efficiency of eco-management in Bulgarian farms with a high eco-activity. First, a brief characterisation of surveyed “eco-active” farms is made. After that, diverse (internal, private, contract, market, formal, informal, hybrid etc.) forms and the scope of eco-management in agricultural farms are analysed. Next, different (ideological, economic, market, social etc.) factors of eco-management in farms are spec...
Extrapolation of π-meson form factor, zeros in the analyticity domain
International Nuclear Information System (INIS)
Morozov, P.T.
1978-01-01
The problem of a stable extrapolation from the cut to an arbitrary interior of the analyticity domain for the pion form factor is formulated and solved. As it is shown a stable solution can be derived if module representations with the Karleman weight function are used as the analyticity conditions. The case when the form factor has zeros is discussed. If there are zeros in the complex plane they must be taken into account when determining the extrapolation function
International Nuclear Information System (INIS)
Lin, C.K.
1983-01-01
The collective model H/sub int/ + H/sub coll/ is used to study the magnetic form factors. For the intrinsic Hamiltonian, we use the Nilsson model to generate the intrinsic state. For the collective Hamiltonian, two models are considered, the rigid body model and the liquid soap model. We use the particle-rotor model to derive the collective operators and their reduced matrix elements, and then apply this model to the elastic M1 form factor of 13 C. One sees clearly the interplay of the intrinsic form factor and the collective form factor. Since the form factor is essentially a Fourier transform of the current density operator, one also sees the effects of the collective current density distribution due to all the particles in addition to that of the intrinsic current due to the unpaired nucleons. The effects of core deformation are explored. This includes discussions on the difference between the variation before projection and the variation after projection. Analytic results are obtained in the case of weak deformations. The collective model focuses on the effects of the quadrupole deformation on the M1 form factor of 13 C, whereas the calculation involving core polarization stresses the monopole effects. By introducing a quenching of the isovector g/sub s/, the fits by the collective models are very comparable to the fit by the core polarization, although the justification for this procedure in light nuclei is questionable
Proton electromagnetic form factors: present status and future perspectives at PANDA
Directory of Open Access Journals (Sweden)
Tomasi-Gustafsson E.
2015-01-01
Full Text Available Data and models on electromagnetic proton form factors are reviewed, highlighting the contribution foreseen by the PANDA collaboration. Electromagnetic hadron form factors contain essential information on the internal structure of hadrons. Precise and surprising data have been obtained at electron accelerators, applying the polarization method in electron-proton elastic scattering. At electron-positron colliders, using initial state radiation, BABAR measured proton time-like form factors in a wide time-like kinematical region and the BESIII collaboration will measure very precisely proton and neutron form factors in the threshold region. In the next future an antiproton beam with momentum up to 15 GeV/c will be available at FAIR (Darmstadt. Measurements of the reaction p̅ + p → e+ + e− by the PANDA collaboration will contribute to the individual determination of electric and magnetic form factors in the time-like region of momentum transfer squared, as well as to their first determination in the unphysical region (below the kinematical threshold, through the reaction p̅ + p → e+ + e− + π0. From the discussion on feasibility studies at PANDA, we focus on the consequences of such measurements in view of an unified description of form factors in the full kinematical region. We present models which have the necessary analytical requirements and apply to the data in the whole kinematical region.
Single-Spin Polarization Effects and the Determination of Timelike Proton Form Factors
Energy Technology Data Exchange (ETDEWEB)
Brodsky, S
2003-10-24
We show that measurements of the proton's polarization in e{sup +}e{sup -} {yields} p{bar p} strongly discriminate between analytic forms of models which fit the proton form factors in the spacelike region. In particular, the single-spin asymmetry normal to the scattering plane measures the relative phase difference between the timelike G{sub E} and G{sub M} form factors. The expected proton polarization in the timelike region is large, of order of several tens of percent.
International Nuclear Information System (INIS)
1976-01-01
An axial tomographic system is described comprising axial tomographic means for collecting sets of data corresponding to the transmission or absorption of a number of beams of penetrating radiation through a planar slice of an object. It includes means to locate an object to be analyzed, a source and detector for directing one or more beams of penetrating radiation through the object from the source to the detector, and means to rotate (and optionally translate) the source as well as means to process the collected sets of data. Data collection, data processing, and data display can each be conducted independently of each other. An additional advantage of the system described is that the raw data (i.e., the originally collected data) are not destroyed by the data processing but instead are retained intact for further reference or use, if needed
Cui, Lixia; Lin, Wenwen; Oei, Tian P. S.
2011-01-01
This study investigated cross-cultural differences in the factor structure and psychometric properties of the Young Schema Questionnaire (short form; YSQ-SF). The participants were 712 Chinese undergraduate students. The total sample was randomly divided into two sub-samples. Exploratory Factor Analysis (EFA) was conducted on questionnaire results…
Multilevel Confirmatory Factor Analysis of the Teacher My Class Inventory-Short Form
Villares, Elizabeth; Mariani, Melissa; Sink, Christopher A.; Colvin, Kimberly
2016-01-01
Researchers analyzed data from elementary teachers (N = 233) to further establish the psychometric soundness of the Teacher My Class Inventory-Short Form. Supporting previous psychometric research, confirmatory factor analyses findings supported the factorial validity of the hypothesized five-factor solution. Internal reliability estimates were…
Charge form factors and alpha-cluster internal structure of 12C
International Nuclear Information System (INIS)
Luk'yanov, V.K.; Zemlyanaya, E.V.; Kadrev, D.N.; Antonov, A.N.; Spasova, K.; Anagnostatos, G.S.; Ginis, P.; Giapitzakis, J.
1999-01-01
The transition densities and form factors of 0 + , 2 + , and 3 - states in 12 C are calculated in alpha-cluster model using the triangle frame with clusters in the vertices. The wave functions of nucleons in the alpha clusters are taken as they were obtained in the framework of the models used for the description of the 4 He form factor and momentum distribution which are based on the one-body density matrix construction. They contain effects of the short-range NN correlations, as well as the d-shell admixtures in 4 He. Calculations and the comparison with the experimental data show that visible effects on the form and magnitude of the 12 C form factors take place, especially at relatively large momentum transfers
International Nuclear Information System (INIS)
Massen, S. E.; Garistov, V. P.; Grypeos, M. E.
1996-01-01
The effects of nuclear surface fluctuations on harmonic oscillator elastic charge form factor of light nuclei are investigated, simultaneously approximating the short-range correlations through a Jastrow correlation factor. Inclusion of the surface fluctuation effects within this description, by truncating the cluster expansion at the two-body part, is found to improve somewhat the fit to the elastic charge form-factor of 16 O and 40 Ca. However, the convergence of the cluster expansion is expected to deteriorate. An additional finding is that surface-fluctuation correlations produce a drastic change in the asymptotic behaviour of the point-proton form-factor, which now falls off quite slowly (i.e. as const.q -4 ) at large values of the momentum transfer q
Sulkosky, V.; Jin, G.; Long, E.; Zhang, Y.-W.; Mihovilovic, M.; Kelleher, A.; Anderson, B.; Higinbotham, D. W.; Širca, S.; Allada, K.; Annand, J. R. M.; Averett, T.; Bertozzi, W.; Boeglin, W.; Bradshaw, P.; Camsonne, A.; Canan, M.; Cates, G. D.; Chen, C.; Chen, J.-P.; Chudakov, E.; De Leo, R.; Deng, X.; Deur, A.; Dutta, C.; El Fassi, L.; Flay, D.; Frullani, S.; Garibaldi, F.; Gao, H.; Gilad, S.; Gilman, R.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, J.-O.; Holmstrom, T.; Huang, J.; Ibrahim, H.; de Jager, C. W.; Jensen, E.; Jiang, X.; Jones, M.; Kang, H.; Katich, J.; Khanal, H. P.; King, P.; Korsch, W.; LeRose, J.; Lindgren, R.; Lu, H.-J.; Luo, W.; Markowitz, P.; Meekins, D.; Meziane, M.; Michaels, R.; Moffit, B.; Monaghan, P.; Muangma, N.; Nanda, S.; Norum, B. E.; Pan, K.; Parno, D.; Piasetzky, E.; Posik, M.; Punjabi, V.; Puckett, A. J. R.; Qian, X.; Qiang, Y.; Qui, X.; Riordan, S.; Saha, A.; Sawatzky, B.; Shabestari, M.; Shahinyan, A.; Shoenrock, B.; John, J. St.; Subedi, R.; Tobias, W. A.; Tireman, W.; Urciuoli, G. M.; Wang, D.; Wang, K.; Wang, Y.; Watson, J.; Wojtsekhowski, B.; Ye, Z.; Zhan, X.; Zhang, Y.; Zheng, X.; Zhao, B.; Zhu, L.; Jefferson Lab Hall A Collaboration
2017-12-01
Background: Measurements of the neutron charge form factor, GEn, are challenging because the neutron has no net charge. In addition, measurements of the neutron form factors must use nuclear targets which require accurately accounting for nuclear effects. Extracting GEn with different targets and techniques provides an important test of our handling of these effects. Purpose: The goal of the measurement was to use an inclusive asymmetry measurement technique to extract the neutron charge form factor at a four-momentum transfer of 1 (GeV/c ) 2 . This technique has very different systematic uncertainties than traditional exclusive measurements and thus serves as an independent check of whether nuclear effects have been taken into account correctly. Method: The inclusive quasielastic reaction 3He ⃗(e ⃗,e') was measured at Jefferson Laboratory. The neutron electric form factor, GEn, was extracted at Q2=0.98 (GeV/c ) 2 from ratios of electron-polarization asymmetries measured for two orthogonal target spin orientations. This Q2 is high enough that the sensitivity to GEn is not overwhelmed by the neutron magnetic contribution, and yet low enough that explicit neutron detection is not required to suppress pion production. Results: The neutron electric form factor, GEn, was determined to be 0.0414 ±0.0077 (stat)±0.0022 (syst) , providing the first high-precision inclusive extraction of the neutron's charge form factor. Conclusions: The use of the inclusive quasielastic 3He ⃗(e ⃗,e') with a four-momentum transfer near 1 (GeV/c ) 2 has been used to provide a unique measurement of GEn. This new result provides a systematically independent validation of the exclusive extraction technique results and implies that the nuclear corrections are understood. This is contrary to the proton form factor where asymmetry and differential cross section measurements have been shown to have large systematic differences.
Feasibility studies of time-like proton electromagnetic form factors at PANDA-FAIR
Energy Technology Data Exchange (ETDEWEB)
Dbeyssi, Alaa; Capozza, Luigi; Deiseroth, Malte; Froehlich, Bertold; Khaneft, Dmitry; Mora Espi, Maria Carmen; Noll, Oliver; Rodriguez Pineiro, David; Valente, Roserio; Zambrana, Manuel; Zimmermann, Iris [Helmholtz-Institut Mainz, Mainz (Germany); Maas, Frank [Helmholtz-Institut Mainz, Mainz (Germany); Institute of Nuclear Physics, Mainz (Germany); PRISMA Cluster of Excellence, Mainz (Germany); Marchand, Dominique; Tomasi-Gustafsson, Egle; Wang, Ying [Institut de Physique Nucleaire, Orsay (France); Collaboration: PANDA-Collaboration
2015-07-01
Electromagnetic form factors are fundamental quantities which describe the intrinsic electric and magnetic distributions of hadrons. Time-like proton form factors are experimentally accessible through the annihilation processes anti p+p <-> e{sup +}+e{sup -}. Their measurement in the time-like region had been limited by the low statistics achieved by the experiments. This contribution reports on the results of Monte Carlo simulations for future measurements of electromagnetic proton form factors at PANDA (antiProton ANnihilation at DArmstadt). In frame of the PANDARoot software, the statistical precision at which the proton form factors will be determined is estimated. The signal (anti p+p → e{sup +}+e{sup -}) identification and the suppression of the main background process (anti p+p → π{sup +}+π{sup -}) are studied. Different methods have been used and/or developed to generate and analyse the processes of interest. The results show that time-like proton form factors will be measured at PANDA with unprecedented statistical accuracy.
On super form factors of half-BPS operators in N=4 super Yang-Mills
Energy Technology Data Exchange (ETDEWEB)
Penante, Brenda; Spence, Bill; Travaglini, Gabriele; Wen, Congkao [Centre for Research in String Theory, School of Physics and Astronomy,Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)
2014-04-11
We compute form factors of half-BPS operators in N=4 super Yang-Mills dual to massive Kaluza-Klein modes in supergravity. These are appropriate supersymmetrisations T{sub k} of the scalar operators Tr (ϕ{sup k}) for any k, which for k = 2 give the chiral part of the stress-tensor multiplet operator. Using harmonic superspace, we derive simple Ward identities for these form factors, which we then compute perturbatively at tree level and one loop. We propose a novel on-shell recursion relation which links form factors with different numbers of fields. Using this, we conjecture a general formula for the n-point MHV form factors of T{sub k} for arbitrary k and n. Finally, we use supersymmetric generalised unitarity to derive compact expressions for all one-loop MHV form factors of T{sub k} in terms of one-loop triangles and finite two-mass easy box functions.
Theoretical constraints and systematic effects in the determination of the proton form factors
Lorenz, I. T.; Meißner, Ulf-G.; Hammer, H.-W.; Dong, Y.-B.
2015-01-01
We calculate the two-photon exchange corrections to electron-proton scattering with nucleon and Δ intermediate states. The results show a dependence on the elastic nucleon and nucleon-Δ -transition form factors used as input which leads to significant changes compared to previous calculations. We discuss the relevance of these corrections and apply them to the most recent and precise data set and world data from electron-proton scattering. Using this, we show how the form factor extraction from these data is influenced by the subsequent inclusion of physical constraints. The determination of the proton charge radius from scattering data is shown to be dominated by the enforcement of a realistic spectral function. Additionally, the third Zemach moment from the resulting form factors is calculated. The obtained radius and Zemach moment are shown to be consistent with Lamb shift measurements in muonic hydrogen.
An exponentially increasing spectral form factor K(τ) for a class of strongly chaotic systems
International Nuclear Information System (INIS)
Aurich, R.; Sieber, M.
1992-11-01
The spectral form factor K(τ) plays a crucial role in the understanding of the statistical properties of quantal energy spectra of strongly chaotic systems in terms of periodic orbits. It allows the computation of those statistics that are bilinear in the spectral density d(E) like the spectral rigidity Δ 3 (L) and the number variance Σ 2 (L). Since Berry's work on the spectral rigidity in terms of periodic orbits, it is generally assumed that the periodic-orbit expression for the spectral form factor universally obeys KCτ) = 1 for τ ≥ 1. Here we show that for a wide class of strongly chaotic systems, including all billiards with Neumann boundary conditions, the semiclassical spectral form factor K(τ) behaves asymptotically as K(τ ∝ e et where c > 0 depends only on the energy E at which the static is considered. (orig.)
Bethe Ansatz and exact form factors of the O(N) Gross Neveu-model
International Nuclear Information System (INIS)
Babujian, Hrachya M.; Foerster, Angela; Karowski, Michael
2016-01-01
We apply previous results on the O(N) Bethe Ansatz http://dx.doi.org/10.1088/1751-8113/45/5/055207, http://arxiv.org/abs/1204.3479, http://dx.doi.org/10.1007/JHEP11(2013)089 to construct a general form factor formula for the O(N) Gross-Neveu model. We examine this formula for several operators, such as the energy momentum, the spin-field and the current. We also compare these results with the 1/N expansion of this model and obtain full agreement. We discuss bound state form factors, in particular for the three particle form factor of the field. In addition for the two particle case we prove a recursion relation for the K-functions of the higher level Bethe Ansatz.
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
Singh, B.; Krusche, B.; Steinacher, M.; Walford, N.; Liu, B.; Liu, H.; Liu, Z.; Shen, X.; Wang, C.; Zhao, J.; Albrecht, M.; Erlen, T.; Fink, M.; Heinsius, F.; Held, T.; Holtmann, T.; Jasper, S.; Keshk, I.; Koch, H.; Kopf, B.; Kuhlmann, M.; Kümmel, M.; Leiber, S.; Mikirtychyants, M.; Musiol, P.; Mustafa, A.; Pelizäus, M.; Pychy, J.; Richter, M.; Schnier, C.; Schröder, T.; Sowa, C.; Steinke, M.; Triffterer, T.; Wiedner, U.; Ball, M.; Beck, R.; Hammann, C.; Ketzer, B.; Kube, M.; Mahlberg, P.; Rossbach, M.; Schmidt, C.; Schmitz, R.; Thoma, U.; Urban, M.; Walther, D.; Wendel, C.; Wilson, A.; Bianconi, A.; Bragadireanu, M.; Caprini, M.; Pantea, D.; Patel, B.; Czyzycki, W.; Domagala, M.; Filo, G.; Jaworowski, J.; Krawczyk, M.; Lisowski, F.; Lisowski, E.; Michałek, M.; Poznański, P.; Płażek, J.; Korcyl, K.; Kozela, A.; Kulessa, P.; Lebiedowicz, P.; Pysz, K.; Schäfer, W.; Szczurek, A.; Fiutowski, T.; Idzik, M.; Mindur, B.; Przyborowski, D.; Swientek, K.; Biernat, J.; Kamys, B.; Kistryn, S.; Korcyl, G.; Krzemien, W.; Magiera, A.; Moskal, P.; Pyszniak, A.; Rudy, Z.; Salabura, P.; Smyrski, J.; Strzempek, P.; Wronska, A.; Augustin, I.; Böhm, R.; Lehmann, I.; Marinescu, D. Nicmorus; Schmitt, L.; Varentsov, V.; Al-Turany, M.; Belias, A.; Deppe, H.; Dzhygadlo, R.; Ehret, A.; Flemming, H.; Gerhardt, A.; Götzen, K.; Gromliuk, A.; Gruber, L.; Karabowicz, R.; Kliemt, R.; Krebs, M.; Kurilla, U.; Lehmann, D.; Löchner, S.; Lühning, J.; Lynen, U.; Orth, H.; Patsyuk, M.; Peters, K.; Saito, T.; Schepers, G.; Schmidt, C.J.; Schwarz, C.; Schwiening, J.; Täschner, A.; Traxler, M.; Ugur, C.; Voss, B.; Wieczorek, P.; Wilms, A.; Zühlsdorf, M.; Abazov, V.; Alexeev, G.; Arefiev, V.A.; Astakhov, V.; Barabanov, M. Yu.; Batyunya, B.V.; Davydov, Y.; Dodokhov, V. Kh.; Efremov, A.; Fechtchenko, A.; Fedunov, A.G.; Galoyan, A.; Grigoryan, S.; Koshurnikov, E.K.; Lobanov, Y. Yu.; Lobanov, V.I.; Makarov, A.F.; Malinina, L.V.; Malyshev, V.; Olshevskiy, A.G.; Perevalova, E.; Piskun, A.A.; Pocheptsov, T.; Pontecorvo, G.; Rodionov, V.; Rogov, Y.; Salmin, R.; Samartsev, A.; Sapozhnikov, M.G.; Shabratova, G.; Skachkov, N.B.; Skachkova, A.N.; Strokovsky, E.A.; Suleimanov, M.; Teshev, R.; Tokmenin, V.; Uzhinsky, V.; Vodopianov, A.; Zaporozhets, S.A.; Zhuravlev, N.I.; Zorin, A.G.; Branford, D.; Glazier, D.; Watts, D.; Böhm, M.; Britting, A.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Dobbs, S.; Seth, K.; Tomaradze, A.; Xiao, T.; Bettoni, D.; Carassiti, V.; Cotta Ramusino, A.; Dalpiaz, P.; Drago, A.; Fioravanti, E.; Garzia, I.; Savrie, M.; Akishina, V.; Kisel, I.; Kozlov, G.; Pugach, M.; Zyzak, M.; Gianotti, P.; Guaraldo, C.; Lucherini, V.; Bersani, A.; Bracco, G.; Macri, M.; Parodi, R.F.; Biguenko, K.; Brinkmann, K.; Di Pietro, V.; Diehl, S.; Dormenev, V.; Drexler, P.; Düren, M.; Etzelmüller, E.; Galuska, M.; Gutz, E.; Hahn, C.; Hayrapetyan, A.; Kesselkaul, M.; Kühn, W.; Kuske, T.; Lange, J.S.; Liang, Y.; Metag, V.; Nanova, M.; Nazarenko, S.; Novotny, R.; Quagli, T.; Reiter, S.; Rieke, J.; Rosenbaum, C.; Schmidt, M.; Schnell, R.; Stenzel, H.; Thöring, U.; Ullrich, M.; Wagner, M.N.; Wasem, T.; Wohlfahrt, B.; Zaunick, H.; Ireland, D.; Rosner, G.; Seitz, B.; Deepak, P.N.; Kulkarni, A.; Apostolou, A.; Babai, M.; Kavatsyuk, M.; Lemmens, P.J.; Lindemulder, M.; Loehner, H.; Messchendorp, J.; Schakel, P.; Smit, H.; Tiemens, M.; van der Weele, J.C.; Veenstra, R.; Vejdani, S.; Dutta, K.; Kalita, K.; Kumar, A.; Roy, A.; Sohlbach, H.; Bai, M.; Bianchi, L.; Büscher, M.; Cao, L.; Cebulla, A.; Dosdall, R.; Gillitzer, A.; Goldenbaum, F.; Grunwald, D.; Herten, A.; Hu, Q.; Kemmerling, G.; Kleines, H.; Lehrach, A.; Nellen, R.; Ohm, H.; Orfanitski, S.; Prasuhn, D.; Prencipe, E.; Pütz, J.; Ritman, J.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Sterzenbach, G.; Stockmanns, T.; Wintz, P.; Wüstner, P.; Xu, H.; Zambanini, A.; Li, S.; Li, Z.; Sun, Z.; Rigato, V.; Isaksson, L.; Achenbach, P.; Corell, O.; Denig, A.; Distler, M.; Hoek, M.; Karavdina, A.; Lauth, W.; Merkel, H.; Müller, U.; Pochodzalla, J.; Sanchez, S.; Schlimme, S.; Sfienti, C.; Thiel, M.; Ahmadi, H.; Ahmed, S.; Bleser, S.; Capozza, L.; Cardinali, M.; Dbeyssi, A.; Deiseroth, M.; Feldbauer, F.; Fritsch, M.; Fröhlich, B.; Jasinski, P.; Kang, D.; Khaneft, D.; Klasen, R.; Leithoff, H.H.; Lin, D.; Maas, F.; Maldaner, S.; Marta, M.; Michel, M.; Espí, M. C. Mora; Morales Morales, C.; Motzko, C.; Nerling, F.; Noll, O.; Pflüger, S.; Pitka, A.; Piñeiro, D. Rodríguez; Sanchez-Lorente, A.; Steinen, M.; Valente, R.; Weber, T.; Zambrana, M.; Zimmermann, I.; Fedorov, A.; Korjik, M.; Missevitch, O.; Boukharov, A.; Malyshev, O.; Marishev, I.; Balanutsa, V.; Balanutsa, P.; Chernetsky, V.; Demekhin, A.; Dolgolenko, A.; Fedorets, P.; Gerasimov, A.; Goryachev, V.; Chandratre, V.; Datar, V.; Dutta, D.; Jha, V.; Kumawat, H.; Mohanty, A.K.; Parmar, A.; Roy, B.; Sonika, G.; Fritzsch, C.; Grieser, S.; Hergemöller, A.; Hetz, B.; Hüsken, N.; Khoukaz, A.; Wessels, J.P.; Khosonthongkee, K.; Kobdaj, C.; Limphirat, A.; Srisawad, P.; Yan, Y.; Barnyakov, M.; Barnyakov, A. Yu.; Beloborodov, K.; Blinov, A.E.; Blinov, V.E.; Bobrovnikov, V.S.; Kononov, S.; Kravchenko, E.A.; Kuyanov, I.A.; Martin, K.; Onuchin, A.P.; Serednyakov, S.; Sokolov, A.; Tikhonov, Y.; Atomssa, E.; Kunne, R.; Marchand, D.; Ramstein, B.; van de Wiele, J.; Wang, Y.; Boca, G.; Costanza, S.; Genova, P.; Montagna, P.; Rotondi, A.; Abramov, V.; Belikov, N.; Bukreeva, S.; Davidenko, A.; Derevschikov, A.; Goncharenko, Y.; Grishin, V.; Kachanov, V.; Kormilitsin, V.; Levin, A.; Melnik, Y.; Minaev, N.; Mochalov, V.; Morozov, D.; Nogach, L.; Poslavskiy, S.; Ryazantsev, A.; Ryzhikov, S.; Semenov, P.; Shein, I.; Uzunian, A.; Vasiliev, A.; Yakutin, A.; Tomasi-Gustafsson, E.; Roy, U.; Yabsley, B.; Belostotski, S.; Gavrilov, G.; Izotov, A.; Manaenkov, S.; Miklukho, O.; Veretennikov, D.; Zhdanov, A.; Makonyi, K.; Preston, M.; Tegner, P.; Wölbing, D.; Bäck, T.; Cederwall, B.; Rai, A.K.; Godre, S.; Calvo, D.; Coli, S.; De Remigis, P.; Filippi, A.; Giraudo, G.; Lusso, S.; Mazza, G.; Mignone, M.; Rivetti, A.; Wheadon, R.; Balestra, F.; Iazzi, F.; Introzzi, R.; Lavagno, A.; Olave, J.; Amoroso, A.; Bussa, M.P.; Busso, L.; De Mori, F.; Destefanis, M.; Fava, L.; Ferrero, L.; Greco, M.; Hu, J.; Lavezzi, L.; Maggiora, M.; Maniscalco, G.; Marcello, S.; Sosio, S.; Spataro, S.; Birsa, R.; Bradamante, F.; Bressan, A.; Martin, A.; Calen, H.; Andersson, W. Ikegami; Johansson, T.; Kupsc, A.; Marciniewski, P.; Papenbrock, M.; Pettersson, J.; Schönning, K.; Wolke, M.; Galnander, B.; Diaz, J.; Chackara, V. Pothodi; Chlopik, A.; Kesik, G.; Melnychuk, D.; Slowinski, B.; Trzcinski, A.; Wojciechowski, M.; Wronka, S.; Zwieglinski, B.; Bühler, P.; Marton, J.; Steinschaden, D.; Suzuki, K.; Widmann, E.; Zmeskal, J.
2016-01-01
The results of simulations for future measurements of electromagnetic form factors at \\PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision at which the proton form factors can be determined is estimated. The signal channel $\\bar p p \\to e^+ e^-$ is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. the $\\bar p p \\to \\pi^+ \\pi^-$, is studied. Furthermore, the background versus signal efficiency, statistic and systematic uncertainties on the extracted proton form factors are evaluated using to the two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam condition and detector performances.
Feasibility studies of time-like proton electromagnetic form factors at overlinePANDA at FAIR
Singh, B.; Erni, W.; Krusche, B.; Steinacher, M.; Walford, N.; Liu, B.; Liu, H.; Liu, Z.; Shen, X.; Wang, C.; Zhao, J.; Albrecht, M.; Erlen, T.; Fink, M.; Heinsius, F.; Held, T.; Holtmann, T.; Jasper, S.; Keshk, I.; Koch, H.; Kopf, B.; Kuhlmann, M.; Kümmel, M.; Leiber, S.; Mikirtychyants, M.; Musiol, P.; Mustafa, A.; Pelizäus, M.; Pychy, J.; Richter, M.; Schnier, C.; Schröder, T.; Sowa, C.; Steinke, M.; Triffterer, T.; Wiedner, U.; Ball, M.; Beck, R.; Hammann, C.; Ketzer, B.; Kube, M.; Mahlberg, P.; Rossbach, M.; Schmidt, C.; Schmitz, R.; Thoma, U.; Urban, M.; Walther, D.; Wendel, C.; Wilson, A.; Bianconi, A.; Bragadireanu, M.; Caprini, M.; Pantea, D.; Patel, B.; Czyzycki, W.; Domagala, M.; Filo, G.; Jaworowski, J.; Krawczyk, M.; Lisowski, F.; Lisowski, E.; Michałek, M.; Poznański, P.; Płażek, J.; Korcyl, K.; Kozela, A.; Kulessa, P.; Lebiedowicz, P.; Pysz, K.; Schäfer, W.; Szczurek, A.; Fiutowski, T.; Idzik, M.; Mindur, B.; Przyborowski, D.; Swientek, K.; Biernat, J.; Kamys, B.; Kistryn, S.; Korcyl, G.; Krzemien, W.; Magiera, A.; Moskal, P.; Pyszniak, A.; Rudy, Z.; Salabura, P.; Smyrski, J.; Strzempek, P.; Wronska, A.; Augustin, I.; Böhm, R.; Lehmann, I.; Nicmorus Marinescu, D.; Schmitt, L.; Varentsov, V.; Al-Turany, M.; Belias, A.; Deppe, H.; Dzhygadlo, R.; Ehret, A.; Flemming, H.; Gerhardt, A.; Götzen, K.; Gromliuk, A.; Gruber, L.; Karabowicz, R.; Kliemt, R.; Krebs, M.; Kurilla, U.; Lehmann, D.; Löchner, S.; Lühning, J.; Lynen, U.; Orth, H.; Patsyuk, M.; Peters, K.; Saito, T.; Schepers, G.; Schmidt, C. J.; Schwarz, C.; Schwiening, J.; Täschner, A.; Traxler, M.; Ugur, C.; Voss, B.; Wieczorek, P.; Wilms, A.; Zühlsdorf, M.; Abazov, V.; Alexeev, G.; Arefiev, V. A.; Astakhov, V.; Barabanov, M. Yu.; Batyunya, B. V.; Davydov, Y.; Dodokhov, V. Kh.; Efremov, A.; Fechtchenko, A.; Fedunov, A. G.; Galoyan, A.; Grigoryan, S.; Koshurnikov, E. K.; Lobanov, Y. Yu.; Lobanov, V. I.; Makarov, A. F.; Malinina, L. V.; Malyshev, V.; Olshevskiy, A. G.; Perevalova, E.; Piskun, A. A.; Pocheptsov, T.; Pontecorvo, G.; Rodionov, V.; Rogov, Y.; Salmin, R.; Samartsev, A.; Sapozhnikov, M. G.; Shabratova, G.; Skachkov, N. B.; Skachkova, A. N.; Strokovsky, E. A.; Suleimanov, M.; Teshev, R.; Tokmenin, V.; Uzhinsky, V.; Vodopianov, A.; Zaporozhets, S. A.; Zhuravlev, N. I.; Zorin, A. G.; Branford, D.; Glazier, D.; Watts, D.; Böhm, M.; Britting, A.; Eyrich, W.; Lehmann, A.; Pfaffinger, M.; Uhlig, F.; Dobbs, S.; Seth, K.; Tomaradze, A.; Xiao, T.; Bettoni, D.; Carassiti, V.; Cotta Ramusino, A.; Dalpiaz, P.; Drago, A.; Fioravanti, E.; Garzia, I.; Savrie, M.; Akishina, V.; Kisel, I.; Kozlov, G.; Pugach, M.; Zyzak, M.; Gianotti, P.; Guaraldo, C.; Lucherini, V.; Bersani, A.; Bracco, G.; Macri, M.; Parodi, R. F.; Biguenko, K.; Brinkmann, K.; Di Pietro, V.; Diehl, S.; Dormenev, V.; Drexler, P.; Düren, M.; Etzelmüller, E.; Galuska, M.; Gutz, E.; Hahn, C.; Hayrapetyan, A.; Kesselkaul, M.; Kühn, W.; Kuske, T.; Lange, J. S.; Liang, Y.; Metag, V.; Nanova, M.; Nazarenko, S.; Novotny, R.; Quagli, T.; Reiter, S.; Rieke, J.; Rosenbaum, C.; Schmidt, M.; Schnell, R.; Stenzel, H.; Thöring, U.; Ullrich, M.; Wagner, M. N.; Wasem, T.; Wohlfahrt, B.; Zaunick, H.; Ireland, D.; Rosner, G.; Seitz, B.; Deepak, P. N.; Kulkarni, A.; Apostolou, A.; Babai, M.; Kavatsyuk, M.; Lemmens, P. J.; Lindemulder, M.; Loehner, H.; Messchendorp, J.; Schakel, P.; Smit, H.; Tiemens, M.; van der Weele, J. C.; Veenstra, R.; Vejdani, S.; Dutta, K.; Kalita, K.; Kumar, A.; Roy, A.; Sohlbach, H.; Bai, M.; Bianchi, L.; Büscher, M.; Cao, L.; Cebulla, A.; Dosdall, R.; Gillitzer, A.; Goldenbaum, F.; Grunwald, D.; Herten, A.; Hu, Q.; Kemmerling, G.; Kleines, H.; Lehrach, A.; Nellen, R.; Ohm, H.; Orfanitski, S.; Prasuhn, D.; Prencipe, E.; Pütz, J.; Ritman, J.; Schadmand, S.; Sefzick, T.; Serdyuk, V.; Sterzenbach, G.; Stockmanns, T.; Wintz, P.; Wüstner, P.; Xu, H.; Zambanini, A.; Li, S.; Li, Z.; Sun, Z.; Xu, H.; Rigato, V.; Isaksson, L.; Achenbach, P.; Corell, O.; Denig, A.; Distler, M.; Hoek, M.; Karavdina, A.; Lauth, W.; Liu, Z.; Merkel, H.; Müller, U.; Pochodzalla, J.; Sanchez, S.; Schlimme, S.; Sfienti, C.; Thiel, M.; Ahmadi, H.; Ahmed, S.; Bleser, S.; Capozza, L.; Cardinali, M.; Dbeyssi, A.; Deiseroth, M.; Feldbauer, F.; Fritsch, M.; Fröhlich, B.; Jasinski, P.; Kang, D.; Khaneft, D.; Klasen, R.; Leithoff, H. H.; Lin, D.; Maas, F.; Maldaner, S.; Martínez, M.; Michel, M.; Mora Espí, M. C.; Morales Morales, C.; Motzko, C.; Nerling, F.; Noll, O.; Pflüger, S.; Pitka, A.; Rodríguez Piñeiro, D.; Sanchez-Lorente, A.; Steinen, M.; Valente, R.; Weber, T.; Zambrana, M.; Zimmermann, I.; Fedorov, A.; Korjik, M.; Missevitch, O.; Boukharov, A.; Malyshev, O.; Marishev, I.; Balanutsa, V.; Balanutsa, P.; Chernetsky, V.; Demekhin, A.; Dolgolenko, A.; Fedorets, P.; Gerasimov, A.; Goryachev, V.; Chandratre, V.; Datar, V.; Dutta, D.; Jha, V.; Kumawat, H.; Mohanty, A. K.; Parmar, A.; Roy, B.; Sonika, G.; Fritzsch, C.; Grieser, S.; Hergemöller, A.; Hetz, B.; Hüsken, N.; Khoukaz, A.; Wessels, J. P.; Khosonthongkee, K.; Kobdaj, C.; Limphirat, A.; Srisawad, P.; Yan, Y.; Barnyakov, M.; Barnyakov, A. Yu.; Beloborodov, K.; Blinov, A. E.; Blinov, V. E.; Bobrovnikov, V. S.; Kononov, S.; Kravchenko, E. A.; Kuyanov, I. A.; Martin, K.; Onuchin, A. P.; Serednyakov, S.; Sokolov, A.; Tikhonov, Y.; Atomssa, E.; Kunne, R.; Marchand, D.; Ramstein, B.; van de Wiele, J.; Wang, Y.; Boca, G.; Costanza, S.; Genova, P.; Montagna, P.; Rotondi, A.; Abramov, V.; Belikov, N.; Bukreeva, S.; Davidenko, A.; Derevschikov, A.; Goncharenko, Y.; Grishin, V.; Kachanov, V.; Kormilitsin, V.; Levin, A.; Melnik, Y.; Minaev, N.; Mochalov, V.; Morozov, D.; Nogach, L.; Poslavskiy, S.; Ryazantsev, A.; Ryzhikov, S.; Semenov, P.; Shein, I.; Uzunian, A.; Vasiliev, A.; Yakutin, A.; Tomasi-Gustafsson, E.; Roy, U.; Yabsley, B.; Belostotski, S.; Gavrilov, G.; Izotov, A.; Manaenkov, S.; Miklukho, O.; Veretennikov, D.; Zhdanov, A.; Makonyi, K.; Preston, M.; Tegner, P.; Wölbing, D.; Bäck, T.; Cederwall, B.; Rai, A. K.; Godre, S.; Calvo, D.; Coli, S.; De Remigis, P.; Filippi, A.; Giraudo, G.; Lusso, S.; Mazza, G.; Mignone, M.; Rivetti, A.; Wheadon, R.; Balestra, F.; Iazzi, F.; Introzzi, R.; Lavagno, A.; Olave, J.; Amoroso, A.; Bussa, M. P.; Busso, L.; De Mori, F.; Destefanis, M.; Fava, L.; Ferrero, L.; Greco, M.; Hu, J.; Lavezzi, L.; Maggiora, M.; Maniscalco, G.; Marcello, S.; Sosio, S.; Spataro, S.; Birsa, R.; Bradamante, F.; Bressan, A.; Martin, A.; Calen, H.; Ikegami Andersson, W.; Johansson, T.; Kupsc, A.; Marciniewski, P.; Papenbrock, M.; Pettersson, J.; Schönning, K.; Wolke, M.; Galnander, B.; Diaz, J.; Pothodi Chackara, V.; Chlopik, A.; Kesik, G.; Melnychuk, D.; Slowinski, B.; Trzcinski, A.; Wojciechowski, M.; Wronka, S.; Zwieglinski, B.; Bühler, P.; Marton, J.; Steinschaden, D.; Suzuki, K.; Widmann, E.; Zmeskal, J.
2016-10-01
Simulation results for future measurements of electromagnetic proton form factors at overlinePANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel bar{p}p→ e+e- is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. bar{p}p→ π+π-, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance.
$B \\to D^{(*)}$ Form Factors from QCD Light-Cone Sum Rules
Faller, S; Klein, Ch; Mannel, T
2009-01-01
We derive new QCD sum rules for $B\\to D$ and $B\\to D^*$ form factors. The underlying correlation functions are expanded near the light-cone in terms of $B$-meson distribution amplitudes defined in HQET, whereas the $c$-quark mass is kept finite. The leading-order contributions of two- and three-particle distribution amplitudes are taken into account. From the resulting light-cone sum rules we calculate all $B\\to \\Dst $ form factors in the region of small momentum transfer (maximal recoil). In the infinite heavy-quark mass limit the sum rules reduce to a single expression for the Isgur-Wise function. We compare our predictions with the form factors extracted from experimental $B\\to \\Dst l \
Partonic structure of neutral pseudoscalars via two photon transition form factors
Raya, Khépani; Ding, Minghui; Bashir, Adnan; Chang, Lei; Roberts, Craig D.
2017-04-01
The γ γ*→ηc ,b transition form factors are computed using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory, and thereby unified with equivalent calculations of electromagnetic pion elastic and transition form factors. The resulting γ γ*→ηc form factor, Gηc(Q2),is consistent with available data; significantly, at accessible momentum transfers, Q2Gη c(Q2) lies well below its conformal limit. These observations confirm that the leading-twist parton distribution amplitudes of heavy-heavy bound states are compressed relative to the conformal limit. A clear understanding of the distribution of valence quarks within mesons thus emerges, a picture which connects Goldstone modes, built from the lightest quarks in nature, with systems containing the heaviest valence quarks that can now be studied experimentally, and highlights basic facts about manifestations of mass within the Standard Model.
New large-Nc relations for the electromagnetic nucleon-to-Δ form factors
International Nuclear Information System (INIS)
Vladimir Pascalutsa; Marc Vanderhaeghen
2006-01-01
We establish relations which express the three N → Δ transition form factors in terms of the nucleon form factors. These relations are based on the known large-N c relation between the N → Δ electric quadrupole moment and the neutron charge radius, and a newly derived large-N c relation between the electric quadrupole (E2) and Coulomb quadrupole (C2) transitions. Namely, in the large-N c limit we find C2=E2. We show that these relations provide predictions for the N → Δ electromagnetic form factors which are found to be in very good agreement with experiment for moderate momentum transfers. They also provide constraints for the N → Δ GPDs
Strong nucleon and Δ-isobar form factors in the quark-confinement model
International Nuclear Information System (INIS)
Efimov, G.V.; Ivanov, M.A.; Lubovitskij, V.E.
1989-01-01
The nucleon and the Δ-isobar are investigated as three-quark systems in the quark-confinement model (QCM). This model is based on two hypotheses. First, quark confinement is accomplished through averaging over some vacuum gluon fields which are assumed to provide the confinement of any colour states. Second, hadrons are treated as collective colourless excitations of quark-gluon interactions. The QCM is applied to low-energy baryon physics. The nucleon magnetic moments and electromagnetic radii, the ratio G A /G V , and the decay width for Δ→pπ are calculated. The behaviour of the electromagnetic and strong meson-nucleon (meson-isobar) form factors is determined for space-like momentum transfers. The results are compared with experimental data for the electromagnetic form factors and phenomenological strong form factors as used in the Bonn potential. 32 refs.; 10 figs.; 4 tabs
Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR
Energy Technology Data Exchange (ETDEWEB)
Singh, B. [Aligarth Muslim Univ., Aligarth (India). Physics Dept.; Erni, W.; Krusche, B. [Basel Univ. (Switzerland); Collaboration: The PANDA Collaboration; and others
2016-10-15
Simulation results for future measurements of electromagnetic proton form factors at PANDA(FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel anti pp → e{sup +}e{sup -} is studied on the basis of two different but consistent procedures. The suppression of the main background channel, i.e. anti pp → π{sup +}π{sup -}, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance. (orig.)
Axial crystals macroscopic symmetry and tensor properties
Czech Academy of Sciences Publication Activity Database
Janovec, Václav
2017-01-01
Roč. 90, č. 1 (2017), s. 1-10 ISSN 0141-1594 Institutional support: RVO:68378271 Keywords : axial * polar * pseudopolar * chiral * enantiomorphism * optical activity Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.060, year: 2016
Measurement of the form factor ratios in semileptonic decays of charm mesons
International Nuclear Information System (INIS)
R. Zaliznyak
1999-01-01
I have measured the form factor ratios r 2 = A 2 (0)/A 1 (0) and r V = V (0)/A 1 (0) in the semileptonic charm meson decay D + → (anti K) *0 e + ν e from data collected by the Fermilab E791 collaboration. Form factors are introduced in the calculation of the hadronic current in semileptonic decays of strange, charm, or bottom mesons, such as D + → (anti K) *0 e + ν e . Semileptonic decays provide insight into quark coupling to the W boson since the leptonic and hadronic amplitudes in the Feynman diagram for the decay are completely separate. There are no strong interactions between the final state leptons and quarks. A number of theoretical models predict the values of the form factors for D + → (anti K) *0 e + ν e , though there is a large range of predictions. E791 is a hadroproduction experiment that recorded over 20 billion interactions with a 500 GeV π - beam incident on five thin targets during the 1991-92 Fermilab fixed-target run. Approximately 3000 D + → (anti K) *0 e + ν e decays are fully reconstructed. In order to extract the form factor ratios from the data, I implement a multidimensional unbinned maximum likelihood fit with a large sample of simulated (Monte Carlo) D + → (anti K) *0 e + ν e events. The large E791 data sample provides the most precise measurement of the form factor ratios to date. The measured values for the form factor ratios are r 2 = 0.71 ± 0.08 ± 0.09 and r V = 1.84 ± 0.11 ± 0.08. These results are in good agreement with some Lattice Gauge calculations. However the agreement with quark model predictions is not as good
Light meson form factors at high Q2 from lattice QCD
Koponen, Jonna; Zimermmane-Santos, André; Davies, Christine; Lepage, G. Peter; Lytle, Andrew
2018-03-01
Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured at small space-like momentum transfer |q2| values up to 2.5 GeV2 by scattering electrons from the pion cloud around a proton. On the other hand, in the limit of very large (or infinite) Q2 = -q2, perturbation theory is applicable. This leaves a gap in the intermediate Q2 where the form factors are not known. As a part of their 12 GeV upgrade Jefferson Lab will measure pion and kaon form factors in this intermediate region, up to Q2 of 6 GeV2. This is then an ideal opportunity for lattice QCD to make an accurate prediction ahead of the experimental results. Lattice QCD provides a from-first-principles approach to calculate form factors, and the challenge here is to control the statistical and systematic uncertainties as errors grow when going to higher Q2 values. Here we report on a calculation that tests the method using an ηs meson, a 'heavy pion' made of strange quarks, and also present preliminary results for kaon and pion form factors. We use the nf = 2 + 1 + 1 ensembles made by the MILC collaboration and Highly Improved Staggered Quarks, which allows us to obtain high statistics. The HISQ action is also designed to have small dicretisation errors. Using several light quark masses and lattice spacings allows us to control the chiral and continuum extrapolation and keep systematic errors in check. Warning, no authors found for 2018EPJWC.17506016.
Strange quark content in the nucleon and the strange quark vector current form factors
International Nuclear Information System (INIS)
Dubnicka, S.; Dubnickova, A.Z.
1996-12-01
A behaviour of the form factors of the nucleon matrix element of the strange quark vector current in the momentum range of the planned measurements in MIT/Bates and CEBAF is predicted theoretically without using any of the experimental information on the nucleon electromagnetic structure. The corresponding leading nonvanishing moments of the nucleon vector strangeness distribution are comparable with the values obtained by other authors in the framework of the method based on the vector meson pole fit of the isoscalar electromagnetic form factors of the nucleon. (author). 16 refs, 2 figs
Constructing Nucleon Operators on a Lattice for Form Factors with High Momentum Transfer
Energy Technology Data Exchange (ETDEWEB)
Syritsyn, Sergey [Stony Brook Univ., NY (United States); Gambhir, Arjun S. [College of William and Mary, Williamsburg, VA (United States); Musch, Bernhard U. [Univ. of Regensburg (Germany); Orginos, Konstantinos [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2017-05-01
We present preliminary results of computing nucleon form factor at high momentum transfer using the 'boosted' or 'momentum' smearing. We use gauge configurations generated with N f = 2 + 1dynamical Wilson-clover fermions and study the connected as well as disconnected contributions to the nucleon form factors. Our initial results indicate that boosted smearing helps to improve the signal for nucleon correlators at high momentum. However, we also find evidence for large excited state contributions, which will likely require variational analysis to isolate the boosted nucleon ground state.
Extraction of the bare form factors for the semi-leptonic Bs decays
International Nuclear Information System (INIS)
Bahr, F.; Banerjee, D.; Koren, M.; Simma, H.; Sommer, R.
2017-01-01
The computation of the form factors for the B s →lν decay is presented. The b quark is treated by means of Heavy Quark Effective Theory, currently in the static approximation. In these proceedings we discuss the extraction of the bare matrix elements from lattice data through a combined fit to two- and three-point correlation functions, as well as by considering suitable ratios. The different methods agree concerning the extracted form factors and approximately 2% accuracy is reached. The non-perturbative renormalization and matching to QCD is described in accompanying proceedings.
On the ππ continuum in the nucleon form factors and the proton radius puzzle
Energy Technology Data Exchange (ETDEWEB)
Hoferichter, M. [University of Washington, Institute for Nuclear Theory, Seattle, WA (United States); Kubis, B.; Ruiz de Elvira, J. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Bonn (Germany); Hammer, H.W. [Technische Universitaet Darmstadt, Institut fuer Kernphysik, Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, ExtreMe Matter Institute EMMI, Darmstadt (Germany); Meissner, U.G. [Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik (Theorie) and Bethe Center for Theoretical Physics, Bonn (Germany); Institut fuer Kernphysik, Institute for Advanced Simulation, and Juelich Center for Hadron Physics, Forschungszentrum Juelich, Juelich (Germany)
2016-11-15
We present an improved determination of the ππ continuum contribution to the isovector spectral functions of the nucleon electromagnetic form factors. Our analysis includes the most up-to-date results for the ππ → anti NN partial waves extracted from Roy-Steiner equations, consistent input for the pion vector form factor, and a thorough discussion of isospin-violating effects and uncertainty estimates. As an application, we consider the ππ contribution to the isovector electric and magnetic radii by means of sum rules, which, in combination with the accurately known neutron electric radius, are found to slightly prefer a small proton charge radius. (orig.)
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.
Czech Academy of Sciences Publication Activity Database
Rozložník, Miroslav; Okulicka-Dłużewska, F.; Smoktunowicz, A.
2015-01-01
Roč. 36, č. 2 (2015), s. 727-751 ISSN 0895-4798 R&D Projects: GA ČR(CZ) GAP108/11/0853 Institutional support: RVO:67985807 Keywords : symmetric indefinite matrices * Cholesky-like factorization * orthogonalization techniques * indefinite bilinear forms * Gram-Schmidt process * rounding error analysis Subject RIV: BA - General Mathematics Impact factor: 1.883, year: 2015
Yao, De-Liang; Alvarez-Ruso, Luis; Vicente-Vacas, Manuel J.
2017-12-01
We calculate the nucleon axial form factor up to the leading one-loop order in a covariant chiral effective field theory with the Δ (1232 ) resonance as an explicit degree of freedom. We fit the axial form factor to the latest lattice QCD data and pin down the relevant low-energy constants. The lattice QCD data, for various pion masses below 400 MeV, can be well described up to a momentum transfer of ˜0.6 GeV . The Δ (1232 ) loops contribute significantly to this agreement. Furthermore, we extract the axial charge and radius based on the fitted values of the low-energy constants. The results are gA=1.237 (74 ) and ⟨rA2⟩=0.263 (38 ) fm2 . The obtained coupling gA is consistent with the experimental value if the uncertainty is taken into account. The axial radius is below but in agreement with the recent extraction from neutrino quasielastic scattering data on deuterium, which has large error bars. Up to our current working accuracy, rA is predicted only at leading order, i.e., the one-loop level. A more precise determination might need terms of O (p5).
The charge form factor of pseudoscalar mesons in a relativistic constituent quark model
Energy Technology Data Exchange (ETDEWEB)
Cardarelli, F.; Pace, E. [Univ. of Rome, Roma (Italy); Grach, I.L. [Inst. of Theoretical and Experimental Physics, Moscow (Russian Federation)] [and others
1994-04-01
The charge form factor of pseudoscalar mesons has been investigated in the light-cone formalism, up to Q{sup 2} relevant to CEBAF energies. The consequences of adopting the meson wave functions generated through the Godfrey-Isgur q{bar q} potential, which reproduces the mass spectra, are discussed.
Current algebra method for form factors and strong decays with hard pions and kaons
International Nuclear Information System (INIS)
Srivastava, P.P.
1969-01-01
The F K /F Π ratio between the kaon and pion decay couplings in one lepton pair, sum rules for Weinberg spectral functions, form factor renormalization of the K l3 decay because of the SU(3) symmetry violation and the calculations of strong decays of the K* and K A strange resonances are presented and discussed. (L.C.) [pt
Factor structure and psychometric properties of the Fertility Problem Inventory–Short Form
Directory of Open Access Journals (Sweden)
Maria Clelia Zurlo
2017-11-01
Full Text Available The study analyses factor structure and psychometric properties of the Italian version of the Fertility Problem Inventory–Short Form. A sample of 206 infertile couples completed the Italian version of Fertility Problem Inventory (46 items with demographics, State Anxiety Scale of State-Trait Anxiety Inventory (Form Y, Edinburgh Depression Scale and Dyadic Adjustment Scale, used to assess convergent and discriminant validity. Confirmatory factor analysis was unsatisfactory (comparative fit index = 0.87; Tucker-Lewis Index = 0.83; root mean square error of approximation = 0.17, and Cronbach’s α (0.95 revealed a redundancy of items. Exploratory factor analysis was carried out deleting cross-loading items, and Mokken scale analysis was applied to verify the items homogeneity within the reduced subscales of the questionnaire. The Fertility Problem Inventory–Short Form consists of 27 items, tapping four meaningful and reliable factors. Convergent and discriminant validity were confirmed. Findings indicated that the Fertility Problem Inventory–Short Form is a valid and reliable measure to assess infertility-related stress dimensions.
Density form factors of the 1D Bose gas for finite entropy states
De Nardis, J.; Panfil, M.
2015-01-01
We consider the Lieb-Liniger model for a gas of bosonic delta-interacting particles. Using Algebraic Bethe Ansatz results we compute the thermodynamic limit of the form factors of the density operator between finite entropy eigenstates such as finite temperature states or generic non-equilibrium
Electric form factors of the octet baryons from lattice QCD and chiral extrapolation
Energy Technology Data Exchange (ETDEWEB)
Shanahan, P.E.; Thomas, A.W.; Young, R.D.; Zanotti, J.M. [Adelaide Univ., SA (Australia). ARC Centre of Excellence in Particle Physics at the Terascale and CSSM; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe, Hyogo (Japan); Pleiter, D. [Forschungszentrum Juelich (Germany). JSC; Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stueben, H. [Hamburg Univ. (Germany). Regionales Rechenzentrum; Collaboration: CSSM and QCDSF/UKQCD Collaborations
2014-03-15
We apply a formalism inspired by heavy baryon chiral perturbation theory with finite-range regularization to dynamical 2+1-flavor CSSM/QCDSF/UKQCD Collaboration lattice QCD simulation results for the electric form factors of the octet baryons. The electric form factor of each octet baryon is extrapolated to the physical pseudoscalar masses, after finite-volume corrections have been applied, at six fixed values of Q{sup 2} in the range 0.2-1.3 GeV{sup 2}. The extrapolated lattice results accurately reproduce the experimental form factors of the nucleon at the physical point, indicating that omitted disconnected quark loop contributions are small. Furthermore, using the results of a recent lattice study of the magnetic form factors, we determine the ratio μ{sub p}G{sub E}{sup p}/G{sub M}{sup p}. This quantity decreases with Q{sup 2} in a way qualitatively consistent with recent experimental results.
Urban form and psychosocial factors: Do they interact for leisure-time walking?
M.A. Beenackers (Marielle); C.B.M. Kamphuis (Carlijn); R. Prins (Remco); J.P. Mackenbach (Johan); A. Burdorf (Alex); F.J. van Lenthe (Frank)
2014-01-01
textabstractINTRODUCTION: This cross-sectional study uses an adaptation of a social-ecological model on the hierarchy of walking needs to explore direct associations and interactions of urban-form characteristics and individual psychosocial factors for leisure-time walking. METHODS: Questionnaire
Energy Technology Data Exchange (ETDEWEB)
Rimal, Dipak [Florida Intl Univ., Miami, FL (United States)
2014-05-01
The electromagnetic form factors are the most fundamental observables that encode information about the internal structure of the nucleon. This dissertation explored dependence of R on kinematic variables such as squared four-momentum transfer (Q^{2}) and the virtual photon polarization parameter (ε).
Eksi, Füsun
2016-01-01
This study intends to examine the psychometric properties of the Turkish version of the short form of the Five-Factor Narcissism Inventory (FFNI-SF). The study group consists of a total of 526 university students (54% were female) whose ages range from 18 to 32. In the translational equivalence study made over a two-week interval, the FFNI-SF…
Constraints on the Kl3 form factors from analyticity and unitarity
Indian Academy of Sciences (India)
2012-10-05
Oct 5, 2012 ... lattice and t is the momentum transfer. Analogously we define the expansion for vector form factor. The purpose of this work is to obtain .... The model independence has a price: we only are able to predict bounds. Nev- ertheless, the precision of the input is already so large, that the bounds are stringent and.
The proton electromagnetic form factor F2 and quark orbital angular ...
Indian Academy of Sciences (India)
We analyse the proton electromagnetic form factor ratio (2)= 2(2)/1(2) as a function of momentum transfer 2 within perturbative QCD. We ﬁnd that the prediction for (2) at large momentum transfer depends on the exclusive quark wave functions, which are unknown. For a wide range of wave functions we ...
Elastic and inelastic form factors of the Ne20 in the Hartree-Fock approximation
International Nuclear Information System (INIS)
Oliveira, S.A.C. de.
1977-01-01
Properties of Ne 20 fundamental band are studied such as particle densities and elastic and inelastic form factors. A two body interaction is used and its matrix elements involve only the independent particle states of the 1s-0d shell [pt
Inelastic magnetic electron scattering form factors of the 26 Mg nucleus
Indian Academy of Sciences (India)
In form factor calculations, the universal sd-shell interaction B for the sd-shell is used with the Michigan three-range Yakawa effective NN interaction as a residual interaction for the core polarization calculations. The wave functions of the radial single-particle matrix elements have been calculated using harmonic oscillator ...
Directory of Open Access Journals (Sweden)
Kyung Ho Sun
2014-10-01
Full Text Available While environmental vibrations are usually in the range of a few hundred Hertz, small-form-factor piezoelectric vibration energy harvesters will have higher resonant frequencies due to the structural size effect. To address this issue, we propose a resonant frequency-down conversion based on the theory of dynamic vibration absorber for the design of a small-form-factor piezoelectric vibration energy harvester. The proposed energy harvester consists of two frequency-tuned elastic components for lowering the first resonant frequency of an integrated system but is so configured that an energy harvesting beam component is inverted with respect to the other supporting beam component for a small form factor. Furthermore, in order to change the unwanted modal characteristic of small separation of resonant frequencies, as is the case with an inverted configuration, a proof mass on the supporting beam component is slightly shifted toward a second proof mass on the tip of the energy harvesting beam component. The proposed small-form-factor design capability was experimentally verified using a fabricated prototype with an occupation volume of 20 × 39 × 6.9 mm3, which was designed for a target frequency of as low as 100 Hz.
Energy Technology Data Exchange (ETDEWEB)
Sun, Kyung Ho; Kim, Young-Cheol [Department of System Dynamics, Korea Institute of Machinery and Materials, 156 Gajeongbuk-Ro, Yuseong-Gu, Daejeon 305-343 (Korea, Republic of); Kim, Jae Eun, E-mail: jekim@cu.ac.kr [School of Mechanical and Automotive Engineering, Catholic University of Daegu, 13-13 Hayang-Ro, Hayang-Eup, Gyeongsan-Si, Gyeongsangbuk-Do 712-702 (Korea, Republic of)
2014-10-15
While environmental vibrations are usually in the range of a few hundred Hertz, small-form-factor piezoelectric vibration energy harvesters will have higher resonant frequencies due to the structural size effect. To address this issue, we propose a resonant frequency-down conversion based on the theory of dynamic vibration absorber for the design of a small-form-factor piezoelectric vibration energy harvester. The proposed energy harvester consists of two frequency-tuned elastic components for lowering the first resonant frequency of an integrated system but is so configured that an energy harvesting beam component is inverted with respect to the other supporting beam component for a small form factor. Furthermore, in order to change the unwanted modal characteristic of small separation of resonant frequencies, as is the case with an inverted configuration, a proof mass on the supporting beam component is slightly shifted toward a second proof mass on the tip of the energy harvesting beam component. The proposed small-form-factor design capability was experimentally verified using a fabricated prototype with an occupation volume of 20 × 39 × 6.9 mm{sup 3}, which was designed for a target frequency of as low as 100 Hz.
The electromagnetic Sigma-to-Lambda hyperon transition form factors at low energies
International Nuclear Information System (INIS)
Granados, Carlos; Leupold, Stefan; Perotti, Elisabetta
2017-01-01
Using dispersion theory the low-energy electromagnetic form factors for the transition of a Sigma to a Lambda hyperon are related to the pion vector form factor. The additionally required input, i.e. the two-pion-Sigma-Lambda amplitudes are determined from relativistic next-to-leading-order (NLO) baryon chiral perturbation theory including the baryons from the octet and optionally from the decuplet. Pion rescattering is again taken into account by dispersion theory. It turns out that the inclusion of decuplet baryons is not an option but a necessity to obtain reasonable results. The electric transition form factor remains very small in the whole low-energy region. The magnetic transition form factor depends strongly on one not very well determined low-energy constant of the NLO Lagrangian. One obtains reasonable predictive power if this low-energy constant is determined from a measurement of the magnetic transition radius. Such a measurement can be performed at the future Facility for Antiproton and Ion Research (FAIR). (orig.)
Urban form and psychosocial factors : Do they interact for leisure-time walking?
Beenackers, Mariëlle A.; Kamphuis, Carlijn B M; Prins, Richard G.; Mackenbach, Johan P.; Burdorf, Alex; Van Lenthe, Frank J.
2014-01-01
INTRODUCTION: This cross-sectional study uses an adaptation of a social-ecological model on the hierarchy of walking needs to explore direct associations and interactions of urban-form characteristics and individual psychosocial factors for leisure-time walking. METHODS: Questionnaire data (n = 736)
The implication of using a fixed form factor in areas under different ...
African Journals Online (AJOL)
The implication of using a fixed form factor in areas under different rainfall and soil conditions for Pinus kesiya in Zambia. ... Trees were sampled from the three plantation groups and 10 sample plots were established in which 10 trees were randomly sampled for cutting. Height and diameter at breast height (dbh) were the ...
Vector form factor of the pion in chiral effective field theory
Directory of Open Access Journals (Sweden)
D. Djukanovic
2015-03-01
Full Text Available The vector form factor of the pion is calculated in the framework of chiral effective field theory with vector mesons included as dynamical degrees of freedom. To construct an effective field theory with a consistent power counting, the complex-mass scheme is applied.
Inelastic magnetic electron scattering form factors of the 26 Mg nucleus
Indian Academy of Sciences (India)
Magnetic electron scattering (3) form factors with core polarization effects, energy levels and (3) values to 3+ states of the 26Mg nucleus have been studied using shell model calculations. The universal sd of the Wildenthal interaction, universal sd-shell interaction A, universal sd-shell interaction B, are used for the ...
Energy Technology Data Exchange (ETDEWEB)
Castillo, A.; Torres, M.; Ortiz, J. J.; Perusquia, R.; Hernandez, J. L.; Montes, J. L. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: jacm@nuclear.inin.mx
2008-07-01
In the present work the preliminary results were obtained with the zoctli system whose purpose is the axial design of assembly of nuclear fuel under certain considerations. For the mentioned design well-know cells were already used and that they have been proven in diverse cycles of operation in the nuclear power plant of Laguna Verde. The design contemplates fuels assemblies of 10x10 and with 2 water channels. The assembly was distributed in 6 axial zones according to its structure. In order to take to end the optimization is was used the well-known technique like Path relinking and to find the group of previous solutions required by this technique uses the technical Taboo search. In order to work with Path relinking, 5 trajectories was taken in to account from a set of 5 previous solutions generated with theTaboo search, the update of the group of solutions is carried out in dynamic form. In the case of the Taboo search it was used a list of variable size, it was implement an aspiration approach, it was used the vector of frequencies and due to the cost of the evaluation of the objective function, only it was review 5% of the vicinity. For the objective function was considered the limit thermal, the axial profile of power, the effective multiplication factor and the margin of having turned off in cold. In order to prove the design system, it was used a balance cycle with a value of reference of 0.9928 for the effective multiplication factor that is equivalent to a produced energy of 10896 MWd/TU at the end of operation to full power. The designed assemblies were placed both in one of lots different from fresh assemblies on which it counts the referred cycle. At the end one a comparison with the results obtained with other techniques and under similar conditions is made. The results obtained until the moment show an appropriate performance of the system. It is possible to indicate that a small inconvenient is the amount of consumed resources of calculation during
The Sudakov form factor at four loops in maximal super Yang-Mills theory
Boels, Rutger H.; Huber, Tobias; Yang, Gang
2018-01-01
The four-loop Sudakov form factor in maximal super Yang-Mills theory is analysed in detail. It is shown explicitly how to construct a basis of integrals that have a uniformly transcendental expansion in the dimensional regularisation parameter, further elucidating the number-theoretic properties of Feynman integrals. The physical form factor is expressed in this basis for arbitrary colour factor. In the nonplanar sector the required integrals are integrated numerically using a mix of sector-decomposition and Mellin-Barnes representation methods. Both the cusp as well as the collinear anomalous dimension are computed. The results show explicitly the violation of quadratic Casimir scaling at the four-loop order. A thorough analysis concerning the reliability of reported numerical uncertainties is carried out.
Axial skeletal CT densitometry
International Nuclear Information System (INIS)
Lampmann, L.E.H.
1982-01-01
Since the discovery of the Roentgen ray a precise and accurate assessment of bone mineral content has been a challenge to many investigators. A number of methods have been developed but no one satisfied. Considering its technical possibilities computed tomography is very promising in determination of bone mineral content (BMC). The new modality enables BMC estimations in the axial skeletal trabecular bone. CT densitometry can be performed on a normal commercially available third generation whole body CT scanner. No dedicated device in a special clinical set-up is necessary. In this study 106 patients, most of them clinically suspected of osteoporosis, were examined. The new method CT densitometry has been evaluated. The results have been correlated to alternative BMC determination methods. (Auth.)
Rpf Proteins Are the Factors of Reactivation of the Dormant Forms of Actinobacteria.
Nikitushkin, V D; Demina, G R; Kaprelyants, A S
2016-12-01
As the response to unfavorable growth conditions, nonsporulating mycobacteria transform into the dormant state with the concomitant formation of the specialized dormant forms characterized by low metabolic activity and resistance to antibiotics. Such dormant cells can be reactivated under the influence of several factors including proteins of Rpf (Resuscitation promoting factor) family, which possess peptidoglycan hydrolase activity and were considered to belong to the group of the autocrine growth factors of the bacteria. Remarkable interest toward Rpf family is determined by its participation in resuscitation of the dormant forms of Mycobacterium tuberculosis, what in turn is the key element in resuscitation of the latent tuberculosis - an infectious disease that affects one third of the World's population. Experiments with Rpf mutant forms and with strains deleted in these proteins revealed a relationship between the enzymatic activity of this protein and its ability to resuscitate mycobacteria both in vitro and in vivo. This review discusses possible mechanisms of Rpf action including those related to possible participation of the products of mycobacterial Rpf-mediated cell wall hydrolysis (muropeptides) as signaling molecules. The unique ability of Rpf proteins to resuscitate the dormant forms of mycobacteria and to stimulate their proliferation would allow these proteins to occupy their niche in medicine - in diagnostics and in creation of antituberculosis subunit vaccines.
Sudakov resummation for subleading SCET currents and heavy-to-light form factors
International Nuclear Information System (INIS)
Hill, Richard J.; Becher, Thomas; Lee, Seung J.; Neubert, Matthias
2004-01-01
The hard-scattering contributions to heavy-to-light form factors at large recoil are studied systematically in soft-collinear effective theory (SCET). Large logarithms arising from multiple energy scales are re-summed by matching QCD onto SCET in two stages via an intermediate effective theory. Anomalous dimensions in the intermediate theory are computed, and their form is shown to be constrained by conformal symmetry. Renormalization-group evolution equations are solved to give a complete leading-order analysis of the hard-scattering contributions, in which all single and double logarithms are re-summed. In two cases, spin-symmetry relations for the soft-overlap contributions to form factors are shown not to be broken at any order in perturbation theory by hard-scattering corrections. One-loop matching calculations in the two effective theories are performed in sample cases, for which the relative importance of renormalization-group evolution and matching corrections is investigated. The asymptotic behavior of Sudakov logarithms appearing in the coefficient functions of the soft-overlap and hard-scattering contributions to form factors is analyzed. (author)
Sudakov Resummation for Subleading SCET Currents and Heavy-to-Light Form Factors
Energy Technology Data Exchange (ETDEWEB)
Hill, R J
2004-04-25
The hard-scattering contributions to heavy-to-light form factors at large recoil are studied systematically in soft-collinear effective theory (SCET). Large logarithms arising from multiple energy scales are resummed by matching QCD onto SCET in two stages via an intermediate effective theory. Anomalous dimensions in the intermediate theory are computed, and their form is shown to be constrained by conformal symmetry. Renormalization-group evolution equations are solved to give a complete leading-order analysis of the hard-scattering contributions, in which all single and double logarithms are resummed. In two cases, spin-symmetry relations for the soft-overlap contributions to form factors are shown not to be broken at any order in perturbation theory by hard-scattering corrections. One-loop matching calculations in the two effective theories are performed in sample cases, for which the relative importance of renormalization-group evolution and matching corrections is investigated. The asymptotic behavior of Sudakov logarithms appearing in the coefficient functions of the soft-overlap and hard-scattering contributions to form factors is analyzed.
López-Medina, Clementina; Dougados, Maxime; Collantes-Estévez, Eduardo; Moltó, Anna
2018-02-20
To describe adherence to recommendations for TNFα blocker (TNFb) initiation and continuation in early axial Spondyloarthropathy (axSpA); and to evaluate the impact of adherence to these recommendations over 5 years of follow-up in the DEvenir des Spondyloarthrites Indifférenciées Récentes (DESIR) cohort. The first 5 years of follow-up of the DESIR early axSpA cohort were analysed. We evaluated adherence to Assessment of SpondyloArthritis International Society (ASAS) 2003/2006, 2016 and European Medicines Agency recommendations in axSpA patients for: TNFb initiation (patients were adherent if they either commenced TNFb therapy when they met the conditions for initiation or if they did not commence TNFb therapy when conditions were not met) and; TNFb continuation (either when they continued TNFb therapy when conditions to continue were met or when they discontinued when conditions were not met). The impact of adherence to these recommendations on functional disability, quality of life and sick-leave days over 5 years was explored. A total of 708 patients were analysed: 440 (62.15%), 389 (54.94%) and 335 (47.32%) were considered adherent to ASAS 2003/2006, 2016 and European Medicines Agency recommendations for TNFb initiation, respectively. Adherence to 2003/2006 and 2016 recommendations for TNFb continuation was observed in 47.37 and 49.39% of patients, respectively. According to over 5 years of follow-up, better outcomes (lower BASFI, higher SF-36 and fewer days of sick leave) were found in patients adhering to recommendations for TNFb commencement and continuation. Less than 50% of patients were treated in agreement with recommendations for TNFb initiation and continuation. Nevertheless, adherence to such recommendations leads to better functional outcomes and fewer days of sick leave, according to long-term follow-up.
The structure of light-front wavefunctions and constraints on hadronic form factors
Energy Technology Data Exchange (ETDEWEB)
Brodsky, S
2003-11-19
We study the analytic structure of light-front wave functions (LFWFs) and its consequences for hadron form factors using an explicitly Lorentz-invariant formulation of the front form. The normal to the light front is specified by a general null vector {omega}{sup {mu}}. The LFWFs with definite total angular momentum are eigenstates of a kinematic angular momentum operator and satisfy all Lorentz symmetries. They are analytic functions of the invariant mass squared of the constituents M{sub 0}{sup 2} = ({Sigma}k{sup {mu}}){sup 2} and the light-cone momentum fractions x{sub i} = k{sub i}{omega}/p{omega} multiplied by invariants constructed from the spin matrices, polarization vectors, and {omega}{sup {mu}}. These properties are illustrated using known nonperturbative eigensolutions of the Wick-Cutkosky model. We analyze the LFWFs introduced by Chung and Coester to describe static and low momentum properties of the nucleons. They correspond to the spin-locking of a quark with the spin of its parent nucleon, together with a positive-energy projection constraint. These extra constraints lead to anomalous dependence of form factors on Q rather than Q{sup 2}. In contrast, the dependence of LFWFs on M{sub 0}{sup 2} implies that hadron form factors are analytic functions of Q{sup 2} in agreement with dispersion theory and perturbative QCD. We show that a model incorporating the leading-twist perturbative QCD prediction is consistent with recent data for the ratio of proton Pauli and Dirac form factors.
Development of a Short Form of the Five-Factor Narcissism Inventory: the FFNI-SF.
Sherman, Emily D; Miller, Joshua D; Few, Lauren R; Campbell, W Keith; Widiger, Thomas A; Crego, Cristina; Lynam, Donald R
2015-09-01
The Five-Factor Narcissism Inventory (FFNI; Glover, Miller, Lynam, Crego, & Widiger, 2012) is a 148-item self-report inventory of 15 traits designed to assess the basic elements of narcissism from the perspective of a 5-factor model. The FFNI assesses both vulnerable (i.e., cynicism/distrust, need for admiration, reactive anger, and shame) and grandiose (i.e., acclaim seeking, arrogance, authoritativeness, entitlement, exhibitionism, exploitativeness, grandiose fantasies, indifference, lack of empathy, manipulativeness, and thrill seeking) variants of narcissism. The present study reports the development of a short-form version of the FFNI in 4 diverse samples (i.e., 2 undergraduate samples, a sample recruited from MTurk, and a clinical community sample) using item response theory. The validity of the resultant 60-item short form was compared against the validity of the full scale in the 4 samples at both the subscale level and the level of the grandiose and vulnerable composites. Results indicated that the 15 subscales remain relatively reliable, possess a factor structure identical to the structure of the long-form scales, and manifest correlational profiles highly similar to those of the long-form scales in relation to a variety of criterion measures, including basic personality dimensions, other measures of grandiose and vulnerable narcissism, and indicators of externalizing and internalizing psychopathology. Grandiose and vulnerable composites also behave almost identically across the short- and long-form versions. It is concluded that the FFNI-Short Form (FFNI-SF) offers a well-articulated assessment of the basic traits comprising grandiose and vulnerable narcissism, particularly when assessment time is limited. (c) 2015 APA, all rights reserved.
THE ROLE OF INSTITUTIONAL FACTORS IN THE CREATION OF NEW FORMS OF ENTREPRENEURSHIP
Directory of Open Access Journals (Sweden)
M. A. Yakhjyaev
2016-01-01
Full Text Available Supporting entrepreneurship in diff erent countries of the world it is realized through the participation of financial and non-financial institutions, which together form the infrastructure for the development of small and medium-sized businesses. In this context, one can not underestimate the infl uence of institutional factors that have a stimulating eff ect on the modeling and the creation of new forms of entrepreneurship.Objectives. The aim of the article is to research and analysis of modern concepts and identifying common trends in the creation of new forms of entrepreneurship.Methodology. Theoretical and methodological basis of research are general scientific principles and laws of economics, analysis and synthesis, review of scientific concepts, leading Russian and foreign specialists in the sphere of small and medium-sized businesses.Results. The role of institutional factors in the creation of new forms of entrepreneurship. The features of the creation of new forms and areas of business through the use of eff ective tools of XXI century, identifies key factors and trends in the development of this market.Conclusions / relevance. The relevance of the article due to the fact that in modern conditions, when the national economy is in the stage of turbulence, it is necessary to find new solutions that will ensure the sustainability of national social and economic development in line with global trends. The theme of the article is selected aspect of sustainable economic development in Russia in view of increase of innovative activity of business that will be achieved, including through the creation of new forms of entrepreneurship.
The Electro-Excitation Form Factors for Low-Lying States of 7Li Nucleus
International Nuclear Information System (INIS)
Dakhl, Z.A.; Salih, L.; Al-Qazaz, B.S.
2010-01-01
The transverse electron scattering form factors have been studied for low -lying excited states of 7 L i nucleus. These states are specified by JπT= (0.478MeV),(4.63MeV) and(6.68MeV). The transitions to these states are taking place by both isoscalar and isovector components. These form factors have been analyzed in the framework of the multi-nucleon configuration mixing of harmonic oscillator shell model with size parameter b r ms=1.74fm. The universal two-body of Cohen-Kurath is used to generate the 1p-shell wave functions. The core polarization effects are included in the calculations through effective g-factors and resolved many discrepancies with experiments. A higher configuration effect outside the 1p-shell model space, such as the 2p-shell, enhances the form factors for q-values and reproduces the data. The present results are compared with other theoretical models. PACS: 25.30.Bf Elastic electron scattering - 25.30.Dh Inelastic electron scattering to specific states - 21.60.Cs Shell model - 27.20. +n 5≤ A ≥19
Society demands for the quality of education as a factor of modern education space forming
Directory of Open Access Journals (Sweden)
Ivanova Svetlana V.
2016-01-01
Full Text Available The authors research the problems of increasing in modern conditions society demands for qualitative characteristics of education services. The quality of education is considered as one of the determining factors of forming educational space. The paper analyzes the influence of social and economic conditions inherent in the post-industrial era on forming and transforming of education space at the modern stage of society development, shows the ways to overcome emerging contradictions. The authors pay special attention to the significance of project approach in solving the problems of improving education quality.
Hsu, Wen-Hsing; Benzel, Edward C; Chen, Tzu-Yung; Chen, Yao-Liang
2008-10-15
Computerized tomography and image processing methodologies were used to analyze the axial and coronal orientation of cervical zygapophysial joints in asymptomatic adults. Surface motions of axial rotation and lateral bending were simulated. The study was designed to obtain the normal distribution and variation of facet orientation (FO) in axial and coronal planes to investigate factors affecting FO and to study the effects of FO on axial rotation and lateral bending. The FO of the subaxial cervical spine is usually evaluated in the sagittal plane. Cervical spine axial and coronal FO is usually considered to be horizontal. The literature reveals no statistical data for axial or coronal FO. Serial thin-sliced computed tomography scans of the cervical spine in asymptomatic adults were input into Image J, National Institutes of Health, image processing software. Bilateral zygapophysial joint angles from C2-C3 to C6-C7 were measured in the axial and coronal planes and collected from 100 subjects. The effect of gender, age, and correlation was analyzed. The surface motions of axial rotation and lateral bending were simulated in Abaqus CAE 6.5. Mathematical facet contact and range of motion were computed. The FO was widely distributed at each level. Gender had no significant association with FO. Age affected FO at most levels. Axial and coronal FO were significantly correlated. The zygapophysial joint of internally rotated/inverted FO contacted more perpendicularly to each other, and mathematical range of motion was smaller. The axial or coronal FO of the subaxial cervical spine was found with more variability. Age was significantly related to FO. Geometrically, internally rotated/inverted FO of axial rotation/lateral bending was morerestricted. The extent of axial rotation and lateral bending was correlated with each other.
Measurement of the form factor ratios in semileptonic decays of charm mesons
Energy Technology Data Exchange (ETDEWEB)
Zaliznyak, Renata [Stanford Univ., CA (United States)
1998-05-01
I have measured the form factor ratios r_{2} = A_{2} (0)/A_{1} (0) and r_{V} = V (0)/A_{1} (0) in the semileptonic charm meson decay D^{+} → $\\bar{K}$^{*0} e^{+}v_{e} from data collected by the Fermilab E791 collaboration. Form factors are introduced in the calculation of the hadronic current in semileptonic decays of strange, charm, or bottom mesons, such as D^{+} → $\\bar{K}$^{*0} e^{+} v_{e} . Semileptonic decays provide insight into quark coupling to the W boson since the leptonic and hadronic amplitudes in the Feynman diagram for the decay are completely separate. There are no strong interactions between the final state leptons and quarks. A number of theoretical models predict the values of the form factors for D^{+} → $\\bar{K}$^{*0} e^{+} v_{e} , though there is a large range of predictions. E791 is a hadroproduction experiment that recorded over 20 billion interactions with a 500 GeV π^{-} beam incident on five thin targets during the 1991-92 Fermilab fixed-target run. Approximately 3000 D^{+} → $\\bar{K}$^{*0} e^{+} v_{e} decays are fully reconstructed. In order to extract the form factor ratios from the data, I implement a multidimensional unbinned maximum likelihood fit with a large sample of simulated (Monte Carlo) D^{+} → $\\bar{K}$^{*0} e^{+}v_{e} events. The large E791 data sample provides the most precise measurement of the form factor ratios to date. The measured values for the form factor ratios are r_{2} = 0.71 ± 0.08 ± 0.09 and r_{V} = 1.84 ± 0.11 ±} 0.08. These results are in good agreement with some Lattice Gauge calculations. However the agreement with quark model predictions is not as good.
Co-axial, high energy gamma generator
Reijonen, Jani Petteri [Princeton, NJ; Gicquel, Frederic [Pennington, NJ
2011-08-16
A gamma ray generator includes an ion source in a first chamber. A second chamber is configured co-axially around the first chamber at a lower second pressure. Co-axially arranged plasma apertures separate the two chambers and provide for restricted passage of ions and gas from the first to the second chamber. The second chamber is formed by a puller electrode having at least one long channel aperture to draw ions from the first chamber when the puller electrode is subject to an appropriate applied potential. A plurality of electrodes rings in the third chamber in third pressure co-axially surround the puller electrode and have at least one channel corresponding to the at least one puller electrode aperture and plasma aperture. The electrode rings increase the energy of the ions to a selected energy in stages in passing between successive pairs of the electrodes by application of an accelerating voltage to the successive pairs of accelerator electrodes. A target disposed co-axially around the plurality of electrodes receives the beam of accelerated ions, producing gamma rays.
Factor XII-independent activation of the bradykinin-forming cascade
DEFF Research Database (Denmark)
Joseph, Kusumam; Tholanikunnel, Baby G; Bygum, Anette
2013-01-01
. Prolonged incubation of plasma deficient in both factor XII and C1-INH led to conversion of prekallikrein to kallikrein and cleavage of HK, as was seen in plasma from patients with hereditary angioedema but not plasma from healthy subjects. CONCLUSIONS: These results indicate that C1-INH stabilizes...... the prekallikrein-HK complex to prevent HK cleavage either by prekallikrein or by prekallikrein-HK autoactivation to generate kallikrein. In patients with hereditary angioedema, kallikrein and bradykinin formation can occur without invoking factor XII activation, although the kallikrein formed can rapidly activate...
Directory of Open Access Journals (Sweden)
Anto Sulaksono
2011-11-01
Full Text Available The differential cross-section of neutrino interaction with dense and warm electron gasses has been calculated by takinginto account the neutrino electromagnetic form factors. The significant effect of electromagnetic properties of neutrinocan be found if the neutrino dipole moment, μ ν , is ≥ 5.10-9 μB and neutrino charge radius, Rv, is ≥ 5.10-6 MeV-1. Theimportance of the retarded correction, detailed balance and Pauli blocking factors is shown and analyzed. Many-bodyeffects on the target matter which are included via random phase approximation (RPA correlation as well as photoneffective mass are also investigated.
High-throughput spectrometer designs in a compact form-factor: principles and applications
Norton, S. M.
2013-05-01
Many compact, portable Raman spectrometers have entered the market in the past few years with applications in narcotics and hazardous material identification, as well as verification applications in pharmaceuticals and security screening. Often, the required compact form-factor has forced designers to sacrifice throughput and sensitivity for portability and low-cost. We will show that a volume phase holographic (VPH)-based spectrometer design can achieve superior throughput and thus sensitivity over conventional Czerny-Turner reflective designs. We will look in depth at the factors influencing throughput and sensitivity and illustrate specific VPH-based spectrometer examples that highlight these design principles.
Recent experimental results for the pi+ electric form factor from Jefferson Lab
International Nuclear Information System (INIS)
The pion holds a special role in our quest to understand hadrons in terms of the underlying degrees of freedom of QCD. It is the lightest mass QCD system and is used as a test case for all models of hadronic structure. While the ?+ form factor (F?) can be calculated using perturbative QCD at large Q2, its calculation in the intermediate Q2 transition region is more complex and model-dependent. Over the past several years, two experiments have been mounted at Jefferson Lab to measure F? over the range of Q2 = 0.6 to 2.45 GeV2. The technique utilizes a precision Rosenbluth separation of the p(e, e'?+)n reaction at low -t. F? is then extracted from the separated longitudinal response function (?L) with the aid of a model. The recent Jefferson Lab data are reviewed, with special emphasis on the extraction of the form factor from the ?L data.
Isospin mixing in the nucleon and He-4 and the nucleon strange electric form-factor
Energy Technology Data Exchange (ETDEWEB)
M. Viviani; R. Schiavilla; B. Kubis; R. Lewis; L. Girlanda; A. Kievsky; L.E. Marcucci; S. Rosati
2007-09-01
In order to isolate the contribution of the nucleon strange electric form factor to the parity-violating asymmetry measured in 4He(\\vec e,e')4He experiments, it is crucial to have a reliable estimate of the magnitude of isospin-symmetry-breaking (ISB) corrections in both the nucleon and 4He. We examine this issue in the present letter. Isospin admixtures in the nucleon are determined in chiral perturbation theory, while those in 4He are derived from nuclear interactions, including explicit ISB terms. A careful analysis of the model dependence in the resulting predictions for the nucleon and nuclear ISB contributions to the asymmetry is carried out. We conclude that, at the low momentum transfers of interest in recent measurements reported by the HAPPEX collaboration at Jefferson Lab, these contributions are of comparable magnitude to those associated with strangeness components in the nucleon electric form factor.
High-precision calculation of the strange nucleon electromagnetic form factors
Energy Technology Data Exchange (ETDEWEB)
Green, Jeremy [Johannes Gutenberg Univ., Mainz (Germany); Meinel, Stefan [Univ. of Arizona, Tucson, AZ (United States); Brookhaven National Lab. (BNL), Upton, NY (United States); Engelhardt, Michael G. [New Mexico State Univ., Las Cruces, NM (United States); Krieg, Stefan [Bergische Univ., Wuppertal (Germany); Julich Supercomputing Centre, Julich (Germany); Laeuchli, Jesse [College of William and Mary, Williamsburg, VA (United States); Negele, John W. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Orginos, Kostas [College of William and Mary, Williamsburg, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pochinsky, Andrew [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Syritsyn, Sergey [Brookhaven National Lab. (BNL), Upton, NY (United States)
2015-08-26
We report a direct lattice QCD calculation of the strange nucleon electromagnetic form factors G^{s}_{E} and G^{s}_{M} in the kinematic range 0 ≤ Q^{2} ≤ 1.2GeV^{2}. For the first time, both G^{s}_{E} and G^{s}_{M} are shown to be nonzero with high significance. This work uses closer-to-physical lattice parameters than previous calculations, and achieves an unprecented statistical precision by implementing a recently proposed variance reduction technique called hierarchical probing. We perform model-independent fits of the form factor shapes using the z-expansion and determine the strange electric and magnetic radii and magnetic moment. As a result, we compare our results to parity-violating electron-proton scattering data and to other theoretical studies.
Measurement of time-like baryon electro-magnetic form factors in BESIII
Energy Technology Data Exchange (ETDEWEB)
Morales Morales, Cristina; Dbeyssi, Alaa [Helmholtz-Institut Mainz (Germany); Ahmed, Samer Ali Nasher; Lin, Dexu; Rosner, Christoph; Wang, Yadi [Helmholtz-Institut Mainz (Germany); Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany); Maas, Frank [Helmholtz-Institut Mainz (Germany); Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany); PRISMA Cluster of Excellence, Johannes Gutenberg-Universitaet Mainz (Germany); Collaboration: BESIII-Collaboration
2016-07-01
BEPCII is a symmetric electron-positron collider located in Beijing running at center-of-mass energies between 2.0 and 4.6 GeV. This energy range allows BESIII experiment to measure baryon form factors both from direct electron-positron annihilation and from initial state radiation processes. We present results on direct electron-positron annihilation into proton anti-proton and preliminary results on direct electron-positron annihilation into lambda anti-lambda based on data collected by BESIII in 2011 and 2012. Finally, expectations on the measurement of nucleon and hyperon electro-magnetic form factors from the BESIII high luminosity energy scan in 2015 and from initial state radiation processes at different center-of-mass energies are also shown.
A note on NMHV form factors from the Graßmannian and the twistor string
Meidinger, David; Nandan, Dhritiman; Penante, Brenda; Wen, Congkao
2017-09-01
In this note we investigate Graßmannian formulas for form factors of the chiral part of the stress-tensor multiplet in N=4 superconformal Yang-Mills theory. We present an all- n contour for the G(3 , n + 2) Graßmannian integral of NMHV form factors derived from on-shell diagrams and the BCFW recursion relation. In addition, we study other G(3 , n + 2) formulas obtained from the connected prescription introduced recently. We find a recursive expression for all n and study its properties. For n ≥ 6, our formula has the same recursive structure as its amplitude counterpart, making its soft behaviour manifest. Finally, we explore the connection between the two Graßmannian formulations, using the global residue theorem, and find that it is much more intricate compared to scattering amplitudes.
Phenomenological analysis of near-threshold periodic modulations of the proton timelike form factor
Bianconi, A.; Tomasi-Gustafsson, E.
2016-03-01
We have recently highlighted the presence of a periodically oscillating 10% modulation in the BABAR Collaboration data on the proton timelike form factors, expressing the deviations from the pointlike behavior of the proton-antiproton electromagnetic current in the reaction e++e-→p ¯+p . Here we deepen our previous data analysis and confirm that in the case of several standard parametrizations it is possible to write the form factor in the form F0+Fosc , where F0 is a parametrization expressing the long-range trend of the form factor (for q2 ranging from the p ¯p threshold to 36 GeV2), and Fosc is a function of the form exp(-B p )cos(C p ) , where p is the relative momentum of the final p ¯p pair. Error bars allow for a clean identification of the main features of this modulation for q2annihilation of p ¯p pairs into multimeson states. We interpret the flux-creating part of the potential as due to the creation of a 1 /q -ranged state when the virtual photon decays into a set of current quarks and antiquarks. This short-lived compact state may be expressed as a sum of several hadronic states including the ones with large mass Qn≫q , that may exist for a time t ˜1 /(Qn-q ) . The decay of these large-mass states leads to an intermediate-stage regeneration of the p ¯p channel.
The off-shell axial anomaly via the γ*π0 → γ transition
International Nuclear Information System (INIS)
Frank, M.R.; Roberts, C.D.
1995-01-01
The γ*π 0 → γ form factor, including the extension off the pion mass-shell, is obtained from a generalized impulse approximation within a QCD-based model field theory known to provide an excellent description of the pion charge form factor. This approach implements dressing of the vertex functions and propagators consistent with dynamical chiral symmetry breaking, gauge invariance, quark confinement and perturbative QCD. Soft nonperturbative behavior, dictated by the axial anomaly, is found to evolve to the perturbative QCD limit only for Q 2 ≥ 20 GeV 2
Measurement of the proton form factor ratio at low momentum transfer
Energy Technology Data Exchange (ETDEWEB)
Friedman, Moshe [Hebrew Univ. of Jerusalem (Israel)
2016-08-01
Experiment E08-007-II measured the proton elastic form factor ratio μG_{E}=G_{M} in the momentum transfer range of Q^{2} ~ 0.02 - 0.08 GeV^{2}, the lowest ever measured by polarization transfer techniques. The experiment was performed at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA during 2012. A polarized electron beam with energies of 1.1, 1.7, and 2.2 GeV was elastically scattered off a polarized solid NH_{3} target. The asymmetries between the cross section of positive and negative helicity states of the beam were determined. These asymmetries can be used to determine the form factor ratio. In this thesis, we present the asymmetry analysis of the experiment, discuss the main challenges and show preliminary results for part of the data. Preliminary asymmetries indicate an increase in the form factor ratio above unity. However, a complete analysis is required before any conclusion can be made. Further analysis is ongoing, and final asymmetry results and form factor extraction is expected during 2017. We also present first results for ^{14}N asymmetries for elastic and quasi-elastic scattering. The measured asymmetries are in agreement with the shell model approximation, within the low accuracy of the measurement. A change in the asymmetry sign between the elastic and the quasi-elastic processes is seen, and should motivate further theoretical studies. These experimental asymmetries will also be useful for systematic studies of other experiments using polarized NH_{3} targets.
Raspberry Pi- A Small, Powerful, Cost Effective and Efficient Form Factor Computer: A Review
Anand Nayyar; Vikram Puri
2015-01-01
Raspberry Pi, an efficient and cost effective credit card sized computer comes under light of sun by United Kingdom-Raspberry Pi foundation with the aim to enlighten and empower computer science teaching in schools and other developing countries. Since its inception, various open source communities have contributed tons towards open source apps, operating systems and various other small form factor computers similar to Raspberry Pi. Till date, researchers, hobbyists and other embe...
Forms and Factors of Animal Products Marketing in the early post-Meiji Years
Ono, Seishi
1982-01-01
As far as the period after the Meiji era is concerned, at its begining marketing of animal products was formed in conlpliance with the properties of products as a public commodity and the amount of investment needed. The former factor depends basically on the divisibility and the preservation possibilities of the products. The latter is the capital needed for marketing and production. 1) Eggs are the most divisible and preservable of all the animal products. Also, hens can be kept with sm...
Mass and form factor effects in spectrum and width of the semileptonic decays of charmed mesons
International Nuclear Information System (INIS)
Fakirov, D.G.
1982-06-01
Semileptonic decays of charmed mesons of F and D types with tau lepton production are considered using as an example the energetically possible decay of D - sub(S) meson in π 0 and tau - . As the mass msub(tau) of tau lepton is big we consider the mass effects in the decay spectrum which are very closely connected to form factor effects in our approach. (author)
A test of the Veneziano - like πNN form factor
International Nuclear Information System (INIS)
Cass, A.; Mckellar, H.J.
1978-01-01
Dominguez' Veneziano-like πNN form factor has been investigated by attempting to use it to fit dsigma/dt data for np → pn and (antiproton)p → (antineutron)n at 8 GeV/c and 23.5 GeV/c in the interval 0 2 . With n=5/2 as proposed by Dominguez it is not possible to fit the data. A fit can be obtaine for other values of n
The nucleon as a test case to calculate vector-isovector form factors at low energies
Leupold, Stefan
2018-01-01
Extending a recent suggestion for hyperon form factors to the nucleon case, dispersion theory is used to relate the low-energy vector-isovector form factors of the nucleon to the pion vector form factor. The additionally required input, i.e. the pion-nucleon scattering amplitudes are determined from relativistic next-to-leading-order (NLO) baryon chiral perturbation theory including the nucleons and optionally the Delta baryons. Two methods to include pion rescattering are compared: a) solving the Muskhelishvili-Omnès (MO) equation and b) using an N/D approach. It turns out that the results differ strongly from each other. Furthermore the results are compared to a fully dispersive calculation of the (subthreshold) pion-nucleon amplitudes based on Roy-Steiner (RS) equations. In full agreement with the findings from the hyperon sector it turns out that the inclusion of Delta baryons is not an option but a necessity to obtain reasonable results. The magnetic isovector form factor depends strongly on a low-energy constant of the NLO Lagrangian. If it is adjusted such that the corresponding magnetic radius is reproduced, then the results for the corresponding pion-nucleon scattering amplitude (based on the MO equation) agree very well with the RS results. Also in the electric sector the Delta degrees of freedom are needed to obtain the correct order of magnitude for the isovector charge and the corresponding electric radius. Yet quantitative agreement is not achieved. If the subtraction constant that appears in the solution of the MO equation is not taken from nucleon+Delta chiral perturbation theory but adjusted such that the electric radius is reproduced, then one obtains also in this sector a pion-nucleon scattering amplitude that agrees well with the RS results.
Diagonal form factors and heavy-heavy-light three-point functions at weak coupling
International Nuclear Information System (INIS)
Hollo, Laszlo; Jiang, Yunfeng; Petrovskii, Andrei
2015-01-01
In this paper we consider a special kind of three-point functions of HHL type at weak coupling in N=4 SYM theory and analyze its volume dependence. At strong coupling this kind of three-point functions were studied recently by Bajnok, Janik and Wereszczynski http://dx.doi.org/10.1007/JHEP09(2014)050. The authors considered some cases of HHL correlator in the su(2) sector and, relying on their explicit results, formulated a conjecture about the form of the volume dependence of the symmetric HHL structure constant to be valid at any coupling up to wrapping corrections. In order to test this hypothesis we considered the HHL correlator in su(2) sector at weak coupling and directly showed that, up to one loop, the finite volume dependence has exactly the form proposed in http://dx.doi.org/10.1007/JHEP09(2014)050. Another side of the conjecture suggests that computation of the symmetric structure constant is equivalent to computing the corresponding set of infinite volume form factors, which can be extracted as the coefficients of finite volume expansion. In this sense, extracting appropriate coefficients from our result gives a prediction for the corresponding infinite volume form factors.
Role of mesons in the electromagnetic form factors of the nucleon
International Nuclear Information System (INIS)
Crawford, C.; Akdogan, T.; Bertozzi, W.; Botto, T.; Clasie, B.; DeGrush, A.; Donnelly, T. W.; Dow, K.; Farkhondeh, M.; Fatemi, R.; Franklin, W.; Gilad, S.; Hasell, D.; Kolster, H.; Lomon, E.; Maschinot, A.; Matthews, J.; Meitanis, N.; Milner, R.; Redwine, R.
2010-01-01
The roles played by mesons in the electromagnetic form factors of the nucleon are explored using as a basis a model containing vector mesons with coupling to the continuum together with the asymptotic Q 2 behavior of perturbative QCD. Specifically, the vector dominance model (GKex) developed by E. L. Lomon is employed, as it is known to be very successful in representing the existing high-quality data published to date. An analysis is made of the experimental uncertainties present when the differences between the GKex model and the data are expanded in orthonormal basis functions. A main motivation for the present study is to provide insight into how the various ingredients in this model yield the measured behavior, including discussions of when dipole form factors are to be expected or not, of which mesons are the major contributors, for instance, at low Q 2 or large distances, and of what effects are predicted from coupling to the continuum. Such insights are first discussed in momentum space, followed by an analysis of how different and potentially useful information emerges when both the experimental and theoretical electric form factors are Fourier transformed to coordinate space. While these Fourier transforms should not be interpreted as ''charge distributions,'' nevertheless the roles played by the various mesons, especially those which are dominant at large or small distance scales, can be explored via such experiment-theory comparisons.
Accessing the Elastic Form-Factors of the $Delta(1232)$ Using the Beam-Normal Asymmetry
Energy Technology Data Exchange (ETDEWEB)
Dalton, Mark M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2016-08-01
The beam-normal single-spin asymmetry, $B_n$, exists in the scattering of high energy electrons, polarized transverse to their direction of motion, from nuclear targets. To first order, this asymmetry is caused by the interference of the one-photon exchange amplitude with the imaginary part of the two-photon exchange amplitude. Measurements of $B_n$, for the production of a $\\Delta(1232)$ resonance from a proton target, will soon become available from the Qweak experiment at Jefferson Lab and the A4 experiment at Mainz. The imaginary part of two-photon exchange allows only intermediate states that are on-shell, including the $\\Delta$ itself. Therefore such data is sensitive to $\\gamma\\Delta\\Delta$, the elastic form-factors of the $\\Delta$. This article will introduce the form-factors of the $\\Delta$, discuss what might be learned about the elastic form-factors from these new data, describe ongoing efforts in calculation and measurement, and outline the possibility of future measurements.
Lattice calculation of electric dipole moments and form factors of the nucleon
Abramczyk, M.; Aoki, S.; Blum, T.; Izubuchi, T.; Ohki, H.; Syritsyn, S.
2017-07-01
We analyze commonly used expressions for computing the nucleon electric dipole form factors (EDFF) F3 and moments (EDM) on a lattice and find that they lead to spurious contributions from the Pauli form factor F2 due to inadequate definition of these form factors when parity mixing of lattice nucleon fields is involved. Using chirally symmetric domain wall fermions, we calculate the proton and the neutron EDFF induced by the C P -violating quark chromo-EDM interaction using the corrected expression. In addition, we calculate the electric dipole moment of the neutron using a background electric field that respects time translation invariance and boundary conditions, and we find that it decidedly agrees with the new formula but not the old formula for F3. Finally, we analyze some selected lattice results for the nucleon EDM and observe that after the correction is applied, they either agree with zero or are substantially reduced in magnitude, thus reconciling their difference from phenomenological estimates of the nucleon EDM.
Axial flow heat exchanger devices and methods for heat transfer using axial flow devices
Koplow, Jeffrey P.
2016-02-16
Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.
Subleading power corrections to the pion-photon transition form factor in QCD
Wang, Yu-Ming; Shen, Yue-Long
2017-12-01
We reconsider QCD factorization for the leading power contribution to the γ * γ → π 0 form factor F γ* γ→ π 0( Q 2) at one loop using the evanescent operator approach, and demonstrate the equivalence of the resulting factorization formulae derived with distinct prescriptions of γ 5 in dimensional regularization. Applying the light-cone QCD sum rules (LCSRs) with photon distribution amplitudes (DAs) we further compute the subleading power contribution to the pion-photon form factor induced by the "hadronic" component of the real photon at the next-to-leading-order in O({α}_s) , with both naive dimensional regularization and 't Hooft-Veltman schemes of γ 5. Confronting our theoretical predictions of F γ* γ→π0 ( Q 2) with the experimental measurements from the BaBar and the Belle Collaborations implies that a reasonable agreement can be achieved without introducing an "exotic" end-point behaviour for the twist-2 pion DA.
Modelling the elastic scattering in diagnostic radiology: the importance of structure form factors
Cardoso, S. C.; Gonçalves, O. D.; Schechter, H.; Eichler, J.
2003-07-01
The importance of structure form factors in describing elastic scattering in diagnostic radiology was studied through a Monte Carlo code built to reproduce scattering in large water samples. The code, developed by us, considers all relevant interactions, including multiple scattering and interference due to scattering by the liquid structure. Geometrical conditions and energies similar to those found in radiology were used. The secondary to primary radiation ratio using the usual free atom approximation and the structure form factor was obtained and both approaches were compared. Calculations of radiological parameters such as the angular distribution of photons incident on the detector and the fraction of scattered photons stopped by anti-scattering grids were also performed considering mammography, thorax and abdomen radiography conditions. The results have shown that S(beta)/P depends on the experimental set-up, being more important for low momentum transfers and sample sizes for which the multiple scattering is not expected to be significant, as in the case of mammography. It was also verified that large samples increase the probability of multiple scattering, masking the structure peak in S(beta) and making the sample structure important just for relatively thin samples. Considering mammography-like geometry, the maximum of the S(beta)/P distribution considering structure form factors occurs around 15° while the correspondent maximum without considering the structure factors occurs around 10° for any sample thickness. S(beta)/P is almost independent of the irradiation field, with the maximum remaining at 15° and 10° for the SFF and FAFF, respectively. The cases studied in this paper stress some conditions in which it is mandatory to use SFF, but since it requires no further significant efforts, the SFF approach is recommended as a standard procedure when describing the elastic scattering process in radiology.
Axial anomalies of Lifshitz fermions
Bakas, Ioannis
2011-01-01
We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z=3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the eta-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2)xU(1) isom...
Characterization of Multiflux Axial Compressors
International Nuclear Information System (INIS)
Brasnarof, Daniel; Kyung Kyu-Hyung; Rivarola, Martin; Gonzalez Jose; Florido, Pablo; Orellano, Pablo; Bergallo, Juan
2003-01-01
In the present work the results of analytical models of performance are compared with experimental data acquired in the multi flux axial compressor test facility, built in The Pilcaniyeu Technological Complex for the SIGMA project.We describe the experimental circuit and the data of the dispersion inside the axial compressor obtained using a tracer gas through one of the annular inlets.The attained results can be used to validate the design code for the multi flux axial compressors and SIGMA industrial plant
Deuteron A(Q2) structure function and the neutron electric form factor
International Nuclear Information System (INIS)
Platchkov, S.; Amroun, A.; Auffret, S.; Cavedon, J.M.; Dreux, P.; Duclos, J.; Frois, B.; Goutte, D.; Hachemi, H.; Martino, J.
1989-01-01
We present new measurements of the deuteron A(Q 2 ) structure function in the momentum transfer region between 1 and 18 fm -2 . The accuracy of the data ranges from 2% to 6%. We investigate the sensitivity of A(Q 2 ) to the nucleon-nucleon interaction and to the neutron electric form factor G E n . Our analysis shows that below 20 fm -2 G E n can be inferred from these data with a significantly improved accuracy. The model dependence of this analysis is discussed
Muon capture in hyperfine states of muonic deuterium and induced pseudoscalar form factor
International Nuclear Information System (INIS)
Morita, M.; Morita, R.
1992-01-01
Muon capture rates from the hyperfine states of the muonic deuterium were studied as the functions of the induced pseudoscalar form factor g P . These capture rates vary also with the πNΔ coupling constants through the meson exchange current effects. Variation is not large, but still, appreciable to limit the magnitude of g P . The ratio of the capture rates from two hyperfine states has a small variation, and it is more sensitive to g P than the muon capture rates. (orig.)
Extraction of the Compton Form Factor H from recent DVCS measurements at Jefferson Lab
International Nuclear Information System (INIS)
Working at twist 2 accuracy and assuming the dominance of the Generalized Parton Distribution H we study the helicity-dependent and independent cross sections measured in Hall A and the beam spin asymmetries measured in Hall B at Jefferson Laboratory. We extract the real and imaginary parts of the Compton Form Factor H, the latter being obtained with a 20-50 % uncertainty. We discuss our results and compare to other extractions as well as to the popular VGG model. We pay extra attention to the estimation of systematic errors on the extraction of H.
First measurement of proton's charge form factor at very low Q2 with initial state radiation
Directory of Open Access Journals (Sweden)
M. Mihovilovič
2017-08-01
Full Text Available We report on a new experimental method based on initial-state radiation (ISR in e–p scattering, which exploits the radiative tail of the elastic peak to study the properties of electromagnetic processes and to extract the proton charge form factor (GEp at extremely small Q2. The ISR technique was implemented in an experiment at the three-spectrometer facility of the Mainz Microtron (MAMI. This led to a precise validation of radiative corrections far away from elastic line and provided first measurements of GEp for 0.001≤Q2≤0.004(GeV/c2.
isospin mixing in the 4He bound state and the nucleon strange form factor
Energy Technology Data Exchange (ETDEWEB)
Rocco Schiavilla
2006-10-11
The contribution of isospin admixtures in the ground state of the {sup 4}He nucleus is studied using wave functions derived from the most modern nuclear interactions, including isospin symmetry breaking terms. The present calculations show that this contribution is larger than previous estimates had indicated. Its effect on parity violating elastic scattering of polarized electrons from {sup 4}He is investigated. In particular, a simple analysis of the recently measured left-right asymmetry at low Q{sup 2} shows that the contribution of these isospin admixtures is of comparable magnitude to that associated with strangeness components in the nucleon electric form factor.
Form factors of exponential fields for two-parametric family of integrable models
International Nuclear Information System (INIS)
Fateev, V.A.; Lashkevich, M.
2004-01-01
A two-parametric family of integrable models (the SS model) that contains as particular cases several well known integrable quantum field theories is considered. After the quantum group restriction it describes a wide class of integrable perturbed conformal field theories. Exponential fields in the SS model are closely related to the primary fields in these perturbed theories. We use the bosonization approach to derive an integral representation for the form factors of the exponential fields in the SS model. The same representations for the sausage model and the cosine-cosine model are obtained as limiting cases. The results are tested at the special points, where the theory contains free particles
Form factors of exponential fields for two-parametric family of integrable models
Fateev, V. A.; Lashkevich, M.
2004-09-01
A two-parametric family of integrable models (the SS model) that contains as particular cases several well known integrable quantum field theories is considered. After the quantum group restriction it describes a wide class of integrable perturbed conformal field theories. Exponential fields in the SS model are closely related to the primary fields in these perturbed theories. We use the bosonization approach to derive an integral representation for the form factors of the exponential fields in the SS model. The same representations for the sausage model and the cosine-cosine model are obtained as limiting cases. The results are tested at the special points, where the theory contains free particles.
arXiv Measurement of the $\\pi^0$ electromagnetic transition form factor slope
Lazzeroni, C.; Romano, A.; Blazek, T.; Koval, M.; Ceccucci, A.; Danielsson, H.; Falaleev, V.; Gatignon, L.; Goy Lopez, S.; Hallgren, B.; Maier, A.; Peters, A.; Piccini, M.; Riedler, P.; Frabetti, P.L.; Gersabeck, E.; Kekelidze, V.; Madigozhin, D.; Misheva, M.; Molokanova, N.; Movchan, S.; Potrebenikov, Yu.; Shkarovskiy, S.; Zinchenko, A.; Rubin, P.; Baldini, W.; Cotta Ramusino, A.; Dalpiaz, P.; Fiorini, M.; Gianoli, A.; Norton, A.; Petrucci, F.; Savrié, M.; Wahl, H.; Bizzeti, A.; Bucci, F.; Iacopini, E.; Lenti, M.; Veltri, M.; Antonelli, A.; Moulson, M.; Raggi, M.; Spadaro, T.; Eppard, K.; Hita-Hochgesand, M.; Kleinknecht, K.; Renk, B.; Wanke, R.; Winhart, A.; Winston, R.; Bolotov, V.; Duk, V.; Gushchin, E.; Ambrosino, F.; Di Filippo, D.; Massarotti, P.; Napolitano, M.; Palladino, V.; Saracino, G.; Anzivino, G.; Imbergamo, E.; Piandani, R.; Sergi, A.; Cenci, P.; Pepe, M.; Costantini, F.; Doble, N.; Giudici, S.; Pierazzini, G.; Sozzi, M.; Venditti, S.; Balev, S.; Collazuol, G.; DiLella, L.; Gallorini, S.; Goudzovski, E.; Lamanna, G.; Mannelli, I.; Ruggiero, G.; Cerri, C.; Fantechi, R.; Kholodenko, S.; Kurshetsov, V.; Obraztsov, V.; Semenov, V.; Yushchenko, O.; D'Agostini, G.; Leonardi, E.; Serra, M.; Valente, P.; Fucci, A.; Salamon, A.; Bloch-Devaux, B.; Peyaud, B.; Engelfried, J.; Coward, D.; Kozhuharov, V.; Litov, L.; Arcidiacono, R.; Bifani, S.; Biino, C.; Dellacasa, G.; Marchetto, F.; Numao, T.; Retière, F.
2017-05-10
The NA62 experiment collected a large sample of charged kaon decays in 2007 with a highly efficient trigger for decays into electrons. A measurement of the $\\pi^{0}$ electromagnetic transition form factor slope parameter from $1.11\\times10^{6}$ fully reconstructed $K^\\pm \\to \\pi^\\pm \\pi^0_D, \\; \\pi^0_D \\to e^+ e^- \\, \\gamma$ events is reported. The measured value $a = \\left(3.68 \\pm 0.57\\right)\\times 10^{-2}$ is in good agreement with theoretical expectations and previous measurements, and represents the most precise experimental determination of the slope in the time-like momentum transfer region.
Nucleon form factors and structure functions from Nf=2 Clover fermions
International Nuclear Information System (INIS)
Collins, S.; Goeckeler, M.; Haegler, P.
2010-12-01
We give an update on our ongoing efforts to compute the nucleon's form factors and moments of structure functions using N f =2 flavours of non-perturbatively improved Clover fermions. We focus on new results obtained on gauge configurations where the pseudo-scalar meson mass is in the range of 170-270 MeV. We compare our results with various estimates obtained from chiral effective theories since we have some overlap with the quark mass region where results from such theories are believed to be applicable. (orig.)
Three-loop massive form factors: complete light-fermion corrections for the vector current
Lee, Roman N.; Smirnov, Alexander V.; Smirnov, Vladimir A.; Steinhauser, Matthias
2018-03-01
We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors F 1 and F 2 involving a closed loop of massless fermions. This subset is gauge invariant and contains both planar and non-planar contributions. We perform the reduction using FIRE and compute the master integrals with the help of differential equations. Our analytic results can be expressed in terms of Goncharov polylogarithms. We provide analytic results for all master integrals which are not present in the large- N c calculation considered in refs. [1, 2].
International Nuclear Information System (INIS)
Naumann, K.H.; Bunz, H.
1994-04-01
This report describes a theoretical concept that establishes a complete link between the form factor characterization and the fractal description of irregularily shaped particles. Of central importance is the approximate consideration of hydrodynamic interactions between the primary particles within the framework of the Kirkwood-Riseman theory, resulting in a clear distinction between the geometric and the hydrodynamic radius of the agglomerates. Furthermore, special attention is given to the description of the density decay in the outer regions of the particles. Using connectivity arguments it is shown that the case of particles with very low fractal dimension (e.g. chainlike species) requires a specific treatment. (orig./HP) [de
All tree-level MHV form factors in N=4 SYM from twistor space
Energy Technology Data Exchange (ETDEWEB)
Koster, Laura [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin (Germany); Mitev, Vladimir [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin (Germany); PRISMA Cluster of Excellence, Institut für Physik, WA THEP,Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz (Germany); Staudacher, Matthias [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin (Germany); Wilhelm, Matthias [Institut für Mathematik, Institut für Physik und IRIS Adlershof,Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, 12489 Berlin (Germany); Niels Bohr Institute, Copenhagen University,Blegdamsvej 17, 2100 Copenhagen (Denmark)
2016-06-28
We incorporate all gauge-invariant local composite operators into the twistor-space formulation of N=4 SYM theory, detailing and expanding on ideas we presented recently in http://arxiv.org/abs/1603.04471. The vertices for these operators contain infinitely many terms and we show how they can be constructed by taking suitable derivatives of a light-like Wilson loop in twistor space and shrinking it down to a point. In particular, these vertices directly yield the tree-level MHV super form factors of all composite operators in N=4 SYM theory.
Bone formation in axial spondyloarthritis.
Lories, Rik J; Haroon, Nigil
2014-10-01
The success of targeted therapies directed against tumor necrosis factor for patients with spondyloarthritis has shifted the focus of physicians and scientists towards the prevention of structural damage to the involved structures, in particular the sacroiliac joints and the spine, to avoid loss of function and disability. Structural damage to the skeleton as witnessed by radiography mainly consists of new bone formation potentially progressively leading to spine or joint ankylosis. This important long-term outcome parameter has been difficult to study, not alone because the time window for change may be long but also because human tissues with direct translational relevance are rarely available. Data from rodent models have identified growth factor signaling pathways as relevant targets. Both human and animal studies have tried to understand the link between inflammation and new bone formation. At the current moment, most evidence points towards a strong link between both but with the question still lingering about the sequence of events, disease triggers, and the interdependence of both features of disease. New discoveries such as a masterswitch T cell population that carries the IL23 receptor and the analysis of auto-antibodies directed again noggin and sclerostin are contributing to innovative insights into the pathophysiology of disease. Long-term data with tumor necrosis factor (TNF) inhibitors also suggest that some window of opportunity may exist to inhibit structural disease progression. All these data provide support for a further critical analysis of the available datasets and boost research in the field. The introduction of novel disease definitions, in particular the characterization of non-radiographic axial spondyloarthritis patients, will likely be instrumental in our further understanding of structural damage. Copyright © 2014 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
A.S. Kolbin
2006-01-01
Full Text Available The aim of the study is to identify the significant factors for the risk of candidemia development among children, suffering from burns. The authors have conducted an analytical retrospective controlling study. It shows that statistically significant factors the risk of candidemia development among children with major heat injury (burns of III–IV degree were the area of the full? Thickness burn over 40% (or boundless, p = 0,008; use of car bapenem class antibiotics (or 0,16 with 95% confidence interval 0,08–0,36, p = 0,023; glycopeptids (or 0,13 with 95% confidence interval 0,05–0,33, p = 0,008; mucosa colonization of the upper respiratory tracts with сandida SPP (or 0,14 with 95% confidence interval 0,06–0,32, p = 0,011. Among patients with the above listed factors for the risk of candidemia development it is necessary to conduct prophylaxis by systemic antimicotics, such as: lipid associated forms of amphotericin в and fluconasol.Key words: children, burns, intrusive candidiasis, risk factors.
Lim, K H; Sumarni, M G; Kee, C C; Christopher, V M; Noruiza Hana, M; Lim, K K; Amal, N M
2010-12-01
A cross-sectional study was conducted among form four students of secondary schools in the District of Petaling, Selangor, Malaysia from February 2008 to June 2008 with the aim of quantifying the prevalence of smoking and identifying the psychosocial factors related to smoking among adolescents in this district. A two-stage stratified sampling strategy was used to obtain a sample of 1300 students based on an estimated prevalence of 10%. The response rate was 80.5% (1045 out of 1298 students). Results showed that prevalence of smoking was higher among male students (22.3%) compared to females (5.5%) and the median age at smoking initiation was lower among males compared to female smokers (14 years old vs 15 years old). Modifiable risk factors associated with smoking were "percentage of friends who smoke" (OR 2.94, 95% CI [1.71- 5.06]) and "having a brother who smokes" (OR 1.97, 95% CI [1.20-3.31]). There was also a correlation between smoking prevalence and the number of risk factors present. Intensification of health education and anti-smoking programmes and modification of external factors in early adolescence are recommended to prevent smoking initiation.
Fluorescence axial nanotomography with plasmonics.
Cade, Nicholas I; Fruhwirth, Gilbert O; Krasavin, Alexey V; Ng, Tony; Richards, David
2015-01-01
We present a novel imaging technique with super-resolution axial sensitivity, exploiting the changes in fluorescence lifetime above a plasmonic substrate. Using conventional confocal fluorescence lifetime imaging, we show that it is possible to deliver down to 6 nm axial position sensitivity of fluorophores in whole biological cell imaging. We employ this technique to map the topography of the cellular membrane, and demonstrate its application in an investigation of receptor-mediated endocytosis in carcinoma cells.
The Proton Coulomb Form Factor from Polarized Inclusive e-p Scattering
Energy Technology Data Exchange (ETDEWEB)
Harris, Christopher Matthew [Univ. of Virginia, Charlottesville, VA (United States)
2001-05-01
The proton form factors provide information on the fundamental properties of the proton and provide a test for models based on QCD. In 1998 at Jefferson Lab (JLAB) in Newport News, VA, experiment E93026 measured the inclusive e-p scattering cross section from a polarized ammonia (^{15}NH_{3}) target at a four momentum transfer squared of Q^{2} = 0.5 (GeV/c)^{2}. Longitudinally polarized electrons were scattered from the polarized target and the scattered electron was detected. Data has been analyzed to obtain the asymmetry from elastically scattered electrons from hydrogen in ^{15}NH_{3}. The asymmetry, A_{p}, has been used to determine the proton elastic form factor G_{Ep}. The result is consistent with the dipole model and data from previous experiments. However, due to the choice of kinematics, the uncertainty in the measurement is large.
Neutron time-like electromagnetic form factor measurement with direct scan method at BESIII
Energy Technology Data Exchange (ETDEWEB)
Larin, Paul; Ahmed, Samer Ali Nasher; Lin, Dexu; Rosner, Christoph; Wang, Yadi [Helmholtz-Institut Mainz (Germany); Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany); Dbeyssi, Alaa; Morales, Cristina [Helmholtz-Institut Mainz (Germany); Maas, Frank [Helmholtz-Institut Mainz (Germany); Institut fuer Kernphysik, Johannes Gutenberg-Universitaet Mainz (Germany); PRISMA Cluster of Excellence, Johannes Gutenberg-Universitaet Mainz (Germany); Collaboration: BESIII-Collaboration
2016-07-01
The internal structure and dynamics of the neutron can be understood through the study of its electromagnetic (EM) form factors (FF). In comparison to proton FF measurements, less data on the neutron is available in the space-like as well as in the time-like region. None of the previous experiments were able to measure the ratio of the electric and the magnetic FF in the time-like region so far. The BESIII (Beijing Spectrometer III) experiment at BEPCII (Beijing Electron Positron Collider II) collected in 2014/15 a large sample of e{sup +}e{sup -} scan data in the region between 2.0 and 3.08 GeV with a total luminosity of 523.5 pb{sup -1}. With this poster we show our efforts to measure the effective FF of the neutron in a large energy region and the possibility to measure for the first time the ratio of the neutron form factors in the time-like region.
Measurements of the deuteron and proton magnetic form factors at large momentum transfers
International Nuclear Information System (INIS)
Bosted, P.E.; Katramatou, A.T.; Arnold, R.G.; Benton, D.; Clogher, L.; DeChambrier, G.; Lambert, J.; Lung, A.; Petratos, G.G.; Rahbar, A.; Rock, S.E.; Szalata, Z.M.; Debebe, B.; Frodyma, M.; Hicks, R.S.; Hotta, A.; Peterson, G.A.; Gearhart, R.A.; Alster, J.; Lichtenstadt, J.; Dietrich, F.; van Bibber, K.
1990-01-01
Measurements of the deuteron elastic magnetic structure function B(Q 2 ) are reported at squared four-momentum transfer values 1.20≤Q 2 ≤2.77 (GeV/c) 2 . Also reported are values for the proton magnetic form factor G Mp (Q 2 ) at 11 Q 2 values between 0.49 and 1.75 (GeV/c) 2 . The data were obtained using an electron beam of 0.5 to 1.3 GeV. Electrons backscattered near 180 degree were detected in coincidence with deuterons or protons recoiling near 0 degree in a large solid-angle double-arm spectrometer system. The data for B(Q 2 ) are found to decrease rapidly from Q 2 =1.2 to 2 (GeV/c) 2 , and then rise to a secondary maximum around Q 2 =2.5 (GeV/c) 2 . Reasonable agreement is found with several different models, including those in the relativistic impulse approximation, nonrelativistic calculations that include meson-exchange currents, isobar configurations, and six-quark configurations, and one calculation based on the Skyrme model. All calculations are very sensitive to the choice of deuteron wave function and nucleon form factor parametrization. The data for G Mp (Q 2 ) are in good agreement with the empirical dipole fit
Measurement of the Hadronic Form factor in D0 to K- e+ nu_e Decays
Energy Technology Data Exchange (ETDEWEB)
Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; /Paris U., VI-VII; Garra Tico, J.; Grauges, E.; /Barcelona U., ECM; Lopez, L.; Palano, A.; /Bari U.; Eigen, G.; Stugu, B.; Sun, L.; /Bergen U.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; Cahn, R.N.; /Energy Sci.
2007-04-09
The shape of the hadronic form factor f{sub +} (q{sup 2}) in the decay D{sup 0} {yields} K{sup -} e{sup +}{nu}{sub e} has been measured in a model independent analysis and compared with theoretical calculations. They use 75 fb{sup -1} of data recorded by the BABAR detector at the PEPII electron-positron collider. The corresponding decay branching fraction, relative to the decay D{sup 0} {yields} K{sup -} {pi}{sup +}, has also been measured to be R{sub D} = BR(D{sup 0} {yields} K{sup -}e{sup +}{nu}{sub e})/BR(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.927 {+-} 0.007 {+-} 0.012. From these results, and using the present world average value for BR(D{sup 0} {yields} K{sup -}{pi}{sup +}), the normalization of the form factor at q{sup 2} = 0 is determined to be f{sub +}(0) = 0.727 {+-} 0.007 {+-} 0.005 {+-} 0.007 where the uncertainties are statistical, systematic, and from external inputs, respectively.
Form factors and scattering amplitudes in N=4 SYM in dimensional and massive regularizations
Energy Technology Data Exchange (ETDEWEB)
Henn, Johannes M. [Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics; Moch, Sven [California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics; Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Naculich, Stephen G. [California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics; Bowdoin College, Brunswick, ME (United States). Dept. of Physics
2011-09-15
The IR-divergent scattering amplitudes of N=4 supersymmetric Yang-Mills theory can be regulated in a variety of ways, including dimensional regularization and massive (or Higgs) regularization. The IR-finite part of an amplitude in different regularizations generally differs by an additive constant at each loop order, due to the ambiguity in separating finite and divergent contributions. We give a prescription for defining an unambiguous, regulator-independent finite part of the amplitude by factoring off a product of IR-divergent ''wedge'' functions. For the cases of dimensional regularization and the common-mass Higgs regulator, we define the wedge function in terms of a form factor, and demonstrate the regularization independence of the n-point amplitude through two loops. We also deduce the form of the wedge function for the more general differential-mass Higgs regulator, although we lack an explicit operator definition in this case. Finally, using extended dual conformal symmetry, we demonstrate the link between the differential-mass wedge function and the anomalous dual conformal Ward identity for the finite part of the scattering amplitude. (orig.)
The Co-axial Flow of Injectable Solid Hydrogels with Encapsulated Cells
Stewart, Brandon; Pochan, Darrin; Sathaye, Sameer
2013-03-01
Hydrogels are quickly becoming an important biomaterial that can be used for the safe, localized injection of cancer drugs, the injection of stem cells into areas of interest or other biological applications. Our peptides can be self-assembled in a syringe where they form a gel, sheared by injection and, once in the body, immediately reform a localized pocket of stiff gel. My project has been designed around looking at the possibility of having a co-axial strand, in which one gel can surround another. This co-axial flow can be used to change the physical properties of our gel during injection, such as stiffening our gel using hyaluronic acid or encapsulating cells in the gel and surrounding the gel with growth medium or other biological factors. Rheology on hyaluron stiffened gels and cells encapsulated in gels was performed for comparison to the results from co-axial flow. Confocal microscopy was used to examine the coaxial gels after flow and to determine how the co-axial nature of the gels is affected by the concentration of peptide.
Stone forming risk factors in patients with type Ia glycogen storage disease.
Scales, Charles D; Chandrashekar, Aravind S; Robinson, Marnie R; Cantor, David A; Sullivan, Jennifer; Haleblian, George E; Leitao, Victor A; Sur, Roger L; Borawski, Kristy M; Koeberl, Dwight; Kishnani, Priya S; Preminger, Glenn M
2010-03-01
Patients with type Ia glycogen storage disease have an increased recurrent nephrolithiasis rate. We identified stone forming risk factors in patients with type Ia glycogen storage disease vs those in stone formers without the disease. Patients with type Ia glycogen storage disease were prospectively enrolled from our metabolic clinic. Patient 24-hour urine parameters were compared to those in age and gender matched stone forming controls. We collected 24-hour urine samples from 13 patients with type Ia glycogen storage disease. Average +/- SD age was 27.0 +/- 13.0 years and 6 patients (46%) were male. Compared to age and gender matched hypocitraturic, stone forming controls patients had profound hypocitraturia (urinary citrate 70 vs 344 mg daily, p = 0.009). When comparing creatinine adjusted urinary values, patients had profound hypocitraturia (0.119 vs 0.291 mg/mg creatinine, p = 0.005) and higher oxalate (0.026 vs 0.021 mg/mg creatinine, p = 0.038) vs other stone formers. Patients with type Ia glycogen storage disease have profound hypocitraturia, as evidenced by 24-hour urine collections, even compared to other stone formers. This may be related to a recurrent nephrolithiasis rate greater than in the overall population. These findings may be used to support different treatment modalities, timing and/or doses to prevent urinary lithiasis in patients with type Ia glycogen storage disease. 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
C-terminal truncated forms of Met, the hepatocyte growth factor receptor.
Prat, M; Crepaldi, T; Gandino, L; Giordano, S; Longati, P; Comoglio, P
1991-12-01
The MET proto-oncogene encodes a transmembrane tyrosine kinase of 190 kDa (p190MET), which has recently been identified as the receptor for hepatocyte growth factor/scatter factor. p190MET is a heterodimer composed of two disulfide-linked chains of 50 kDa (p50 alpha) and 145 kDa (p145 beta). We have produced four different monoclonal antibodies that are specific for the extracellular domain of the Met receptor. These antibodies immunoprecipitate with p190MET two additional Met proteins of 140 and 130 kDa. The first protein (p140MET) is membrane bound and is composed of an alpha chain (p50 alpha) and an 85-kDa C-terminal truncated beta chain (p85 beta). The second protein (p130MET) is released in the culture supernatant and consists of an alpha chain (p50 alpha) and a 75-kDa C-terminal truncated beta chain (p75 beta). Both truncated forms lack the tyrosine kinase domain. p140MET and p130MET are consistently detected in vivo, together with p190MET, in different cell lines or their culture supernatants. p140MET is preferentially localized at the cell surface, where it is present in roughly half the amount of p190MET. The two C-terminal truncated forms of the Met receptor are also found in stable transfectants expressing the full-length MET cDNA, thus showing that they originate from posttranslational proteolysis. This process is regulated by protein kinase C activation. Together, these data suggest that the production of the C-terminal truncated Met forms may have a physiological role in modulating the Met receptor function.
International Nuclear Information System (INIS)
Steshenko, A.I.; Maksimenko, V.N.
1983-01-01
A method for calculating the matrix elements of a nuclear form factor operator in the basis of collective functions Sp(2,R) is proposed. The formulas obtained can be used in the calculatings of the charged elastic and transition form factors for the collective states of maqic and near magic nuclei by means of the generalized hyperspherical function method
DEFF Research Database (Denmark)
Pedersen, Susanne J; Wichuk, Stephanie; Chiowchanwisawakit, Praveena
2014-01-01
INTRODUCTION: Radiography is an unreliable and insensitive tool for the assessment of structural lesions in the sacroiliac joints (SIJ). Magnetic resonance imaging (MRI) detects a wider spectrum of structural lesions but has undergone minimal validation in prospective studies. The Spondyloarthritis...... Research Consortium of Canada (SPARCC) MRI Sacroiliac Joint (SIJ) Structural Score (SSS) assesses a spectrum of structural lesions (erosion, fat metaplasia, backfill, ankylosis) and its potential to discriminate between therapies requires evaluation. METHODS: The SSS score assesses five consecutive coronal......). Two readers independently scored 147 pairs (baseline, 2 years) of scans from a prospective cohort of patients with SpA who received either standard (n = 69) or tumor necrosis factor alpha (TNFα) inhibitor (n = 78) therapy. Smallest detectable change (SDC) was calculated using analysis of variance...
Analysis tools for precision studies of hadronic three-body decays and transition form factors
Energy Technology Data Exchange (ETDEWEB)
Schneider, Sebastian Philipp
2013-02-14
Due to the running coupling constant of Quantum Chromodynamics one of the pillars of the Standard Model, the strong interactions, is still insufficiently understood at low energies. In order to describe the interactions of hadrons that form in this physical regime, one has to devise methods that are non-perturbative in the strong coupling constant. In particular hadronic three-body decays and transition form factors present a great challenge due to the complex analytic structure ensued by strong final-state interactions. In this thesis we present two approaches to tackle these processes. In the first part we use a modified version of non-relativistic effective field theory to analyze the decay {eta}{yields}3{pi}. This perturbative low-energy expansion is ideally suited to study the effects of {pi}{pi} rescattering and contributes greatly to the understanding of the slope parameter of the {eta}{yields}3{pi}{sup 0} Dalitz plot, a quantity that is strongly influenced by final-state interactions and has presented a long-standing puzzle for theoretical approaches. In the second part we present dispersion relations as a non-perturbative means to study three-particle decays. Using the example of {eta}'{yields}{eta}{pi}{pi} we give a detailed introduction to the framework and its numerical implementation. We confront our findings with recent experimental data from the BES-III and VES collaborations and discuss whether the extraction of {pi}{eta} scattering parameters, one of the prime motives to study this decay channel, is feasible in such an approach. A more clear-cut application is given in our study of the decays {omega}/{phi}{yields}3{pi} due to the relative simplicity of this decay channel: our results are solely dependent on the {pi}{pi} P-wave scattering phase shift. We give predictions for the Dalitz plot distributions and compare our findings to very precise data on {phi}{yields}3{pi} by the KLOE and CMD-2 collaborations. We also predict Dalitz plot
Computing the nucleon charge and axial radii directly at Q2=0 in lattice QCD
Hasan, Nesreen; Green, Jeremy; Meinel, Stefan; Engelhardt, Michael; Krieg, Stefan; Negele, John; Pochinsky, Andrew; Syritsyn, Sergey
2018-02-01
We describe a procedure for extracting momentum derivatives of nucleon matrix elements on the lattice directly at Q2=0 . This is based on the Rome method for computing momentum derivatives of quark propagators. We apply this procedure to extract the nucleon isovector magnetic moment and charge radius as well as the isovector induced pseudoscalar form factor at Q2=0 and the axial radius. For comparison, we also determine these quantities with the traditional approach of computing the corresponding form factors, i.e. GEv(Q2) and GMv(Q2) for the case of the vector current and GPv(Q2) and GAv(Q2) for the axial current, at multiple Q2 values followed by z -expansion fits. We perform our calculations at the physical pion mass using a 2HEX-smeared Wilson-clover action. To control the effects of excited-state contamination, the calculations were done at three source-sink separations and the summation method was used. The derivative method produces results consistent with those from the traditional approach but with larger statistical uncertainties especially for the isovector charge and axial radii.
The K->π vector form factor at zero momentum transfer on the lattice
International Nuclear Information System (INIS)
Becirevic, D.; Isidori, G.; Lubicz, V.; Martinelli, G.; Mescia, F.; Simula, S.; Tarantino, C.; Villadoro, G.
2005-01-01
We present a quenched lattice study of the form factors f+(q2) and f0(q2) of the matrix elements . We focus on the second-order SU(3)-breaking quantity [1-f+(0)], which is necessary to extract |Vus| from K-bar 3 decays. For this quantity we show that it is possible to reach the percent precision which is the required one for a significant determination of |Vus|. The leading quenched chiral logarithms are corrected for by using analytic calculations in quenched chiral perturbation theory. Our final result, f+K0π-(0)=0.960+/-0.005stat+/-0.007syst, where the systematic error does not include the residual quenched effects, is in good agreement with the estimate made by Leutwyler and Roos. A comparison with other non-lattice computations and the impact of our result on the extraction of |Vus| are also presented
The d(e, e'p)n reaction and the nuetron electric form factor
International Nuclear Information System (INIS)
Dieperink, A.E.L.
1978-01-01
An accurate determination of the electric form factor of the neutron, Gsub(En), is important both for our understanding of the structure of the nucleons, and for the description of electron scattering on nuclear many-body systems. At present only reliable model-independent information on Gsub(En) is available for four-momentum transfer (qsub(μ)) 2 →0 from the scattering of thermal neutrons off atoms. Electron scattering offers the possibility to obtain information at higher (qsub(μ)) 2 . However, since electrons can only be scattered off neutrons embedded in a many-body target the extraction of Gsub(En) will in general be affected by nuclear structure uncertainties. Some methods to obtain information on Gsub(En) in e-d experiments are discussed. (Auth.)
Structural studies of formic acid using partial form-factor analysis
International Nuclear Information System (INIS)
Swan, G.; Dore, J.C.; Bellissent-Funel, M.C.
1993-01-01
Neutron diffraction measurements have been made of liquid formic acid using H/D isotopic substitution. Data are recorded for samples of DCOOD, HCOOD and a (H/D)COOD mixture (α D =0.36). A first-order difference method is used to determine the intra-molecular contribution through the introduction of a partial form-factor analysis technique incorporating a hydrogen-bond term. The method improves the sensitivity of the parameters defining the molecular geometry and avoids some of the ambiguities arising from terms involving spatial overlap of inter- and intra-molecular features. The possible application to other systems is briefly reviewed. (authors). 8 figs., 2 tabs., 8 refs
Nucleon Elastic and Transition form factors from the Dyson-Schwinger Equations
Cloet, Ian
2017-09-01
Recent progress in the bound-state problem in continuum QCD has produced a consistent treatment of the nucleon and its resonances. These studies predict the presence of strong diquark correlations within baryons, whose impact on the nucleon elastic and transition form factors will be illustrated. For example, the Roper resonance is found to be the nucleon's first radial excitation and consists of a core of three dressed-quarks whose charge radius is 80% larger than the proton analogue. This core is complemented by a meson cloud which reduces the observed Roper mass by about 20%, however the quark core is revealed to probes with Q2 > 3MN2 . This work was supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, Contract No. DE-AC02-06CH11357.
International Nuclear Information System (INIS)
Hirata, Y.; Orth, D.N.
1981-01-01
Epidermal growth factor (EGF), a 53 amino acid polypeptide, was first isolated by Cohen. EGF's growth-promoting activity is not limited to epidermal cells, but is expressed on a wide variety of tissues derived from a number of different species. Human EGF (hEGF) was isolated and subsequently purified from human urine. Unexpectedly, a close structural relationship was recognized between mEGF and human β-urogastrone. The authors recently developed both an homologous hEGF radioimmunoassay (RIA) and a radioreceptor assay (RRA) using a human placental membrane fraction. Using these assays, the molecular size of hEGF in human body fluids and tissues was evaluated, and partial characterization of a high molecular weight form of hEGF isolated from human urine was carried out. The concentrations of immunoreactive hEGF were also determined in human tissues and plasma after extraction either with cationic exchange chromatography or with immunoaffinity chromatography. (Auth.)
Scaling study of the pion electroproduction cross sections and the pion form factor
International Nuclear Information System (INIS)
Tanja Horn; Xin Qian; John Arrington; Razmik Asaturyan; Fatiha Benmokthar; Werner Boeglin; Peter Bosted; Antje Bruell; Eric Christy; Eugene Chudakov; Ben Clasie; Mark Dalton; AJI Daniel; Donal Day; Dipangkar Dutta; Lamiaa El Fassi; Rolf Ent; Howard Fenker; J. Ferrer; Nadia Fomin; H. Gao; K Garrow; Dave Gaskell; C Gray; G. Huber; M. Jones; N Kalantarians; C. Keppel; K Kramer; Y Li; Y Liang; A. Lung; S Malace; P. Markowitz; A. Matsumura; D. Meekins; T Mertens; T Miyoshi; H. Mykrtchyan; R. Monson; T. Navasardyan; G. Niculescu; I. Niculescu; Y. Okayasu; A. Opper; C Perdrisat; V. Punjabi; A. Rauf; V. Rodriguez; D. Rohe; J Seely; E Segbefia; G. Smith; M. Sumihama; V. Tadevoyan; L Tang; V. Tvaskis; A. Villano; W. Vulcan; F. Wesselmann; S. Wood; L. Yuan; X. Zheng
2007-01-01
The 1 H(e,e(prime)π + )n cross section was measured for a range of four-momentum transfer up to Q 2 =3.91 GeV 2 at values of the invariant mass, W, above the resonance region. The Q 2 -dependence of the longitudinal component is consistent with the Q 2 -scaling prediction for hard exclusive processes. This suggests that perturbative QCD concepts are applicable at rather low values of Q 2 . Pion form factor results, while consistent with the Q 2 -scaling prediction, are inconsistent in magnitude with perturbative QCD calculations. The extraction of Generalized Parton Distributions from hard exclusive processes assumes the dominance of the longitudinal term. However, transverse contributions to the cross section are still significant at Q 2 =3.91 GeV 2
arXiv Conformal anomaly of generalized form factors and finite loop integrals
Chicherin, Dmitry
We reveal a new mechanism of conformal symmetry breaking at Born level. It occurs in generalized form factors with several local operators and an on-shell state of massless particles. The effect is due to hidden singularities on collinear configurations of the momenta. This conformal anomaly is different from the holomorphic anomaly of amplitudes. We present a number of examples in four and six dimensions. We find an application of the new conformal anomaly to finite loop momentum integrals with one or more massless legs. The collinear region around a massless leg creates a contact anomaly, made visible by the loop integration. The anomalous conformal Ward identity for an $\\ell-$loop integral is a 2nd-order differential equation whose right-hand side is an $(\\ell-1)-$loop integral. We show several examples, in particular the four-dimensional scalar double box.
Neutron electric form factor up to Q2 = 1.47 GeV/c2
International Nuclear Information System (INIS)
Madey, Richard; Semenov, Andrei; Taylor, S.; Aghalaryan, Aram; Crouse, Erick; MacLachlan, Glen; Plaster, Bradley; Shigeyuki Tajima; William Tireman; Chenyu Yan; Abdellah Ahmidouch; Brian Anderson; Hartmuth Arenhovel; Razmik Asaturyan; Baker, O.; Alan Baldwin; Herbert Breuer; Roger Carlini; Christy, E.; Steve Churchwell; Leon Cole; Areg Danagoulian; Donal Day; Mostafa Elaasar; Rolf Ent; Manouchehr Farkhondeh; Howard Fenker; John Finn; Liping Gan; Kenneth Garrow; Paul Gueye; Calvin Howell; Bitao Hu; Mark Jones; James Kelly; Cynthia Keppel; Mahbubul Khandaker; Wooyoung Kim; Stanley Kowalski; Allison Lung; David Mack; Manley, D.; Pete Markowitz; Joseph Mitchell; Hamlet Mkrtchyan; Allena Opper; Charles Perdrisat; Vina Punjabi; Brian Raue; Tilmann Reichelt; Joerg Reinhold; Julie Roche; Yoshinori Sato; Irina Semenova; Wonick Seo; Neven Simicevic; Smith, G.; Samuel Stepanyan; Vardan Tadevosyan; Liguang Tang; Paul Ulmer; William Vulcan; Watson, J. W.; Steven Wells; Frank Wesselmann; Stephen Wood; Chen Yan; Seunghoon Yang; Lulin Yuan; Wei-Ming Zhang; Hong Guo Zhu; Xiaofeng Zhu
2003-01-01
The ratio of the electric to the magnetic form factor of the neutron, g /equiv G En /G Mn , was measured via recoil polarimetry (R.G. Arnold, C.E. Carlson, F. Gross, Phys. Rev. C 23, 363 (1981)) from the quasielastic 2 H (/mathop(e)/limitse' /mathop(n)/limits) 1H reaction at three values of Q 2 (viz, 0.45, 1.15, and 1.47 (GeV/c) 2 ) in Hall C of the Thomas Jefferson National Accelerator Facility. The data reveal that GEn continues to follow the Galster parameterization up to Q 2 = 1.15 (GeV/c) 2 and rises above the Galster parameterization at Q 2 = 1.47 (GeV/c) 2
Nyberg, E; Stieglitz, R-D; Flury, M; Riecher-Rössler, A
2013-06-01
BACKGROUND AND HYPOTHESES: Domestic violence is common and can lead to severe physical and psychological problems. Thus, we have investigated the frequency of occurrence, forms and risk factors of domestic violence against female patients on a crisis intervention ward. 115 women were screened with the "screening spouse violence" (SPG) and the "index of spouse abuse" (ISA). The life time prevalence concerning spouse violence was 70 %. Out of 74 women who were currently living in a relationship 28 (38 % )were victims of violence in the last 12 months prior to their admission. Women who experienced violence had a significantly lower level of education. Screening for domestic violence in female patients in the field of crisis intervention and psychiatry should become a standard of "good clinical practice". © Georg Thieme Verlag KG Stuttgart · New York.
Neutral Pion Transition Form Factor Measurement and Run Control at the NA62 experiment
AUTHOR|(CDS)2082375; Goudzovski, Evgueni
The measurement of the 0 electromagnetic transition form factor (TFF) slope a is performed in the time-like region of momentum transfer using a sample of 1.1 $10^6$ $\\pi^0 \\to e^+ e^- \\gamma$ Dalitz decays collected at the NA62-RK experiment in 2007. The event selection, the fit procedure and the study of the systematic ffects are presented. The final result obtained $a = (3.68 \\pm 0.51stat \\pm 0.25syst) \\times 10^{-2} $ is the most precise to date and represents the first evidence of a non-zero $\\pi^0$ TFF slope with more than 3 $\\sigma$ significance. The NA62 experiment based at the CERN SPS is currently taking data and aims at measuring the branching fraction of the $K \\to \\pi \
Supersymmetric axial anomalies and the Wess-Zumino action
International Nuclear Information System (INIS)
Harada, K.; Shizuya, K.
1988-01-01
We derive, by an algebraic method, a manifestly supersymmetric extension of Bardeen's minimal form of axial anomalies, which obeys the Wess-Zumino consistency condition. The left-right symmetric form of the anomalies is also obtained by a reduction procedure. We construct the supersymmetric Wess-Zumino effective action and study its low-energy features. (orig.)
Measurement of the electromagnetic form factors of $\\pi$ and $K$ mesons at the SPS
2002-01-01
This experiment will measure the electro-magnetic form factors of $\\pi$ and K mesons by determining the elastic scattering cross sections of these particles from stationary electrons in a liquid hydrogen target. It is planned to use an incident beam momentum of 300 GeV/c which corresponds to a maximum four momentum transfer of 0.29 (GeV/c)$^{2}$ for $\\pi$-e scattering and of 0.17 (GeV/c)$^{2}$ for K-e scattering. \\\\ \\\\ The apparatus will consist of the forward spectrometer of the NA1 experiment as described in proposal SPSC/74-15/P6 and addenda, preceded by modules of multiwire proportional chambers which determine the trajectories of the incident and scattered particles. The event trigger will be produced by scintillation counters arranged to discriminate against the strong interaction background and by the identification of one of the scattered particles as an electron by the photon detectors which form part of the forward spectrometer.
Snowden, Austyn; Watson, Roger; Stenhouse, Rosie; Hale, Claire
2015-12-01
To examine the construct validity of the Trait Emotional Intelligence Questionnaire Short form. Emotional intelligence involves the identification and regulation of our own emotions and the emotions of others. It is therefore a potentially useful construct in the investigation of recruitment and retention in nursing and many questionnaires have been constructed to measure it. Secondary analysis of existing dataset of responses to Trait Emotional Intelligence Questionnaire Short form using concurrent application of Rasch analysis and confirmatory factor analysis. First year undergraduate nursing and computing students completed Trait Emotional Intelligence Questionnaire-Short Form in September 2013. Responses were analysed by synthesising results of Rasch analysis and confirmatory factor analysis. Participants (N = 938) completed Trait Emotional Intelligence Questionnaire Short form. Rasch analysis showed the majority of the Trait Emotional Intelligence Questionnaire-Short Form items made a unique contribution to the latent trait of emotional intelligence. Five items did not fit the model and differential item functioning (gender) accounted for this misfit. Confirmatory factor analysis revealed a four-factor structure consisting of: self-confidence, empathy, uncertainty and social connection. All five misfitting items from the Rasch analysis belonged to the 'social connection' factor. The concurrent use of Rasch and factor analysis allowed for novel interpretation of Trait Emotional Intelligence Questionnaire Short form. Much of the response variation in Trait Emotional Intelligence Questionnaire Short form can be accounted for by the social connection factor. Implications for practice are discussed. © 2015 John Wiley & Sons Ltd.
Joint resummation for pion wave function and pion transition form factor
Energy Technology Data Exchange (ETDEWEB)
Li, Hsiang-nan [Institute of Physics, Academia Sinica,Academia Rd., Taipei, Taiwan 115 (China); Department of Physics, National Cheng-Kung University,University Rd., Tainan, Taiwan 701 (China); Department of Physics, National Tsing-Hua University,Kuang-Fu Rd., Hsinchu, Taiwan 300 (China); Shen, Yue-Long [College of Information Science and Engineering, Ocean University of China,Songling Rd, Qingdao, Shandong 266100 (China); Wang, Yu-Ming [Institut für Theoretische Teilchenphysik und Kosmologie RWTH Aachen,Physikzentrum Otto-Blumenthal-Straße, D-52056 Aachen (Germany); Physik Department T31, Technische Universität München,James-Franck-Straße, D-85748 Garching (Germany)
2014-01-03
We construct an evolution equation for the pion wave function in the k{sub T} factorization formalism, whose solution sums the mixed logarithm ln xln k{sub T} to all orders, with x (k{sub T}) being a parton momentum fraction (transverse momentum). This joint resummation induces strong suppression of the pion wave function in the small x and large b regions, b being the impact parameter conjugate to k{sub T}, and improves the applicability of perturbative QCD to hard exclusive processes. The above effect is similar to those from the conventional threshold resummation for the double logarithm ln{sup 2} x and the conventional k{sub T} resummation for ln{sup 2} k{sub T}. Combining the evolution equation for the hard kernel, we are able to organize all large logarithms in the γ{sup ∗}π{sup 0}→γ scattering, and to establish a scheme-independent k{sub T} factorization formula. It will be shown that the significance of next-to-leading-order contributions and saturation behaviors of this process at high energy differ from those under the conventional resummations. It implies that QCD logarithmic corrections to a process must be handled appropriately, before its data are used to extract a hadron wave function. Our predictions for the involved pion transition form factor, derived under the joint resummation and the input of a non-asymptotic pion wave function with the second Gegenbauer moment a{sub 2}=0.05, match reasonably well the CLEO, BaBar, and Belle data.
International Nuclear Information System (INIS)
Constantia Alexandrou; Bojan Bistrovic; Robert Edwards; P de Forcrand; George Fleming; Philipp Haegler; John Negele; Konstantinos Orginos; Andrew Pochinsky; Dru Renner; David Richards; Wolfram Schroers; Antonios Tsapalis
2005-01-01
Lattice QCD is an essential complement to the current and anticipated DOE-supported experimental program in hadronic physics. In this poster we address several key questions central to our understanding of the building blocks of nuclear matter, nucleons and pions. Firstly, we describe progress at computing the electromagnetic form factors of the nucleon, describing the distribution of charge and current, before considering the role played by the strange quarks. We then describe the study of transition form factors to the Delta resonance. Finally, we present recent work to determine the pion form factor, complementary to the current JLab experimental determination and providing insight into the approach to asymptotic freedom
International Nuclear Information System (INIS)
Liu Guangqing; Lou Xianhong; Li Zhenqiu
2008-01-01
Reduced form exciting factors of governing mineralization are discussed. It is indicated that metallogenic conditions of hydrothermal uranium deposits of reduced form exciting factors governing mineralization are ore-forming solution flow into metallogenic space; Eh decreases significantly, and reach reducing condition of mineral deposit. The exciting factors of governing mineralization are divided into internal reduction subclass and environment reduction subclass. Then emphases on the classification, characteristic, formation condition, representative deposits and prospecting significance in this paper. The environment reduction index is put forward to evaluate reducing power of surrounding rock. (authors)
Energy Technology Data Exchange (ETDEWEB)
Constantia Alexandrou; Bojan Bistrovic; Robert Edwards; P de Forcrand; George Fleming; Philipp Haegler; John Negele; Konstantinos Orginos; Andrew Pochinsky; Dru Renner; David Richards; Wolfram Schroers; Antonios Tsapalis
2005-10-01
Lattice QCD is an essential complement to the current and anticipated DOE-supported experimental program in hadronic physics. In this poster we address several key questions central to our understanding of the building blocks of nuclear matter, nucleons and pions. Firstly, we describe progress at computing the electromagnetic form factors of the nucleon, describing the distribution of charge and current, before considering the role played by the strange quarks. We then describe the study of transition form factors to the Delta resonance. Finally, we present recent work to determine the pion form factor, complementary to the current JLab experimental determination and providing insight into the approach to asymptotic freedom.
Clinical and genetic risk factors for biofilm-formingStaphylococcus aureus.
Luther, Megan K; Parente, Diane M; Caffrey, Aisling R; Daffinee, Katie; Lopes, Vrishali V; Martin, Emily T; LaPlante, Kerry L
2018-03-12
Background. Molecular and clinical factors associated with biofilm-forming methicillin-resistant Staphylococcus aureus (MRSA) are incompletely understood. Methods. Biofilm production was quantified in 182 MRSA isolates from clinical culture sites (2004-2013). Microbiologic toxins, pigmentation, and genotypes were evaluated, and patient demographics were collected. Logistic regression was used to quantify the effect of strong biofilm production (versus weak) on clinical outcomes and independent predictors of strong biofilm. Results. Of isolates evaluated, 25.8% (47/182) produced strong biofilm, and 40.7% (74/182) produced weak biofilm. Strong biofilm-producing isolates were more likely to be from MLST clonal complex 8 (34.0% vs. 14.9%; P=0.01), but less likely to be from MLST CC5 (48.9% vs. 73.0%, P=0.007). Predictors for strong biofilm were spa type t008 (aOR 4.54 95%CI 1.21-17.1), and receiving chemotherapy or immunosuppressants in the previous 90 days (aOR 33.6; 95%CI 1.68-673). Conversely, patients with high serum creatinine (aOR 0.33; 95%CI 0.15-0.72) or who previously received vancomycin (aOR 0.03; 95%CI 0.002-0.39) were less likely to harbor strong biofilm-producing MRSA. Beta-toxin producing isolates (aOR 0.31; 95%CI 0.11-0.89) and isolates with spa type t895 (aOR 0.02 95%CI <0.001-0.47) were less likely to produce strong biofilm. Patient outcomes also varied between the two groups. Specifically, patients with strong biofilm-forming MRSA were significantly more likely to be readmitted within 90 days (aOR 5.43; 95%CI 1.69-17.4), but tended to have decreased 90 day mortality (aOR 0.36; 95%CI 0.12-1.06). Conclusions: Patients that harbored t008 and received immunosuppressants were more likely to have a strong biofilm-producing MRSA. Clinically, patients with strong biofilm-forming MRSA were less likely to die at 90 days, but five times more likely to be re-admitted. Copyright © 2018 American Society for Microbiology.
Temperature dependence of the field-induced magnetic form factor of the intermetallic compound PrSn3
International Nuclear Information System (INIS)
Loong, C.; Stassis, C.; Zarestky, J.; McMasters, O.D.; Moon, R.M.
1984-01-01
The spatial distribution of the magnetization induced by a magnetic field of 42.5 kG in a single crystal of PrSn 3 has been studied at 100 and 20 K using polarized neutron scattering techniques. We find that at both temperatures the measured form factor is in good agreement with the theoretical 4f magnetic form factor of the Pr 3+ ion. This result is in contrast to the large deviations from the 4f magnetic form factor of Ce 3+ observed, at low temperatures, for the mixed-valence compounds CeSn 3 and CePd 3 . The localized static susceptibility of PrSn 3 at 100 and 20 K, obtained by extrapolating the measured form factor to the forward direction, agrees very well with bulk susceptibility measurements
Energy Technology Data Exchange (ETDEWEB)
Peters, Gerhard
2008-05-15
In this work the leading-twist next-to-leading order (NLO) correction to the light-cone sum rules prediction for the electromagnetic form factors of the nucleon are calculated. Here the Ioffe nucleon interpolation current is used and it is worked in the M{sub N}=0 approximation, with M{sub N} being the mass of the nucleon. In this approximation, only the Pauli form factor F{sub 2} receives a correction and the calculated correction is quite sizable. The numerical results for the proton form factors show the improved agreement with the experimental data. Furthermore the problems encountered when going away from M{sub N}=0 approximation at NLO, as well as, gauge invariance of the perturbative results are discussed. This work presents the first step towards the NLO accuracy in the light-cone sum rules for baryon form factors. (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.
Ankylosing Spondylitis versus Nonradiographic Axial Spondyloarthritis
DEFF Research Database (Denmark)
Glintborg, Bente; Sørensen, Inge J; Østergaard, Mikkel
2017-01-01
OBJECTIVE: To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders....../disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm]. RESULTS: The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients...
Axial structure of the nucleon
Energy Technology Data Exchange (ETDEWEB)
Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner
2002-01-01
We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.
Axial stability of Taylor bubbles
Lu, X.; Prosperetti, Andrea
2006-01-01
Long gas bubbles rising in a vertical tube are observed to lose axial symmetry and become unstable in a downward liquid flow. In this paper an approximate linear stability analysis of this phenomenon is presented. It is found that, under the combined effect of gravity and the pressure gradient which
International Nuclear Information System (INIS)
Dubnicka, S.; Martinovic, L.
1988-01-01
Using precise experimental information on the imaginary part of the pion form factor from e + e - → π + π - up to the inelastic threshold and QCD constraints for it in the range of momenta (m π 0 +m ω ) 2 < t < infinity, was investigated by means of a dispersion integral the reliability of individual electroproduction CEA and Cornell model-dependent pion form factor data points
International Nuclear Information System (INIS)
Bagdasaryan, A.S.; Esaybegyan, S.V.; Ter-Isaakyan, N.L.
1982-01-01
In a model of hadrons composed of relativistic quarks a description of meson static characteristics and pion electromagnetic form factor in the range of small and intermediate values of momentum transfer 0 2 2 have obtained. It is shown that in such a model the data available on the pion electromagnetic form factor may be described basing on a simplest quark without gluon exchange. The contribution of a one-gluon exchange diagram in such a model cannot exceed 30%
One-loop corrections to the pion form factor in QCD
International Nuclear Information System (INIS)
Radyushkin, A.V.; Khalmuradov, R.S.
1985-01-01
The approach based on the operator expansions is applied to study the power corrections to the asymptotic behaviour of the pion form factor corresponding to the contribution of the pseudoscalar operators. Operators correspond to the coefficient function Esup(pp)(x, y;Qsup(2)). The general structure is studied of the most singular in the limit of small fractions x, y contribution to the coefficient function Esup(pp) (x, y; Qsup(2)) and its cancellation is demonstrated with the analogous contribution to the coefficient function Esup(TP) (x, y; Qsup(2)) corresponding to the interference between the T- and P-projections. The influence is investigated of this cancellation on the structure of the one-loop contributions into Esup(PP)(x, y; Qsup(2)). The methods developed can be applied for the calculation of the one-loop corrections to other projections (Esup(PT), Esup(TP), Esup(TT) of the coefficient function related to the twist-3 two-quark operators
Measurement of the g_{πNN}(t) Form Factor
Energy Technology Data Exchange (ETDEWEB)
Vansyoc, Kelley Gene [Old Dominion Univ., Norfolk, VA (United States)
2001-08-01
Cross sections were measured for the reaction 1H(e, e' π^{+} )n at the energy W = 1.95 GeV and momentum transfer Q ^{2} = 0.6 (GeV/c) ^{2} . At this W and Q ^{2} , the longitudinal cross section is dominated by t-channel production, giving a unique opportunity to examine the strong coupling form factor g _{πNN}(t). The measured cross sections were separated using a method similar to a Rosenbluth separation. For the extraction of g _{πNN} (t), the Actor and Korner model [42] and a parameterization of the MAID2000 model [3] were employed to fit the longitudinal cross section. Three parameterizations g_{πNN}(π) were used in both models. These fits resulted in a strong coupling constant g_{πNN}(m$2\\atop{2}$) that is consistent with theoretical predictions. However, this coupling constant leads to a cutoff parameter that is less than 1 GeV.
Proton electromagnetic form factors: Basic notions, present achievements and future perspectives
Energy Technology Data Exchange (ETDEWEB)
Pacetti, Simone, E-mail: simone.pacetti@pg.infn.it [Dipartimento di Fisica e Geologia dell’Universitá degli Studi di Perugia and INFN Sezione di Perugia, 06123 Perugia (Italy); Baldini Ferroli, Rinaldo [INFN, Laboratori Nazionali di Frascati, 00044 Frascati (Italy); Tomasi-Gustafsson, Egle [CEA, IRFU, SPhN, Saclay, 91191 Gif-sur-Yvette Cedex (France); CNRS/IN2P3, Institut de Physique Nucléaire, UMR 8608, 91406 Orsay (France)
2015-01-20
The aim of this report is to give basic notions on electromagnetic hadron form factors (FFs), as they are understood at the present time, to summarize and analyze the present experimental results and available theoretical models and to open a view on future perspectives. FFs are fundamental quantities, which describe the internal, dynamical structure of hadrons. Although the theoretical formalism was settled in the middle of last century, as well as the first experiments in electron–proton elastic scattering for which R. Hofstadter got the Nobel prize in 1961, a renewed activity is due to recent, surprising results and to the opening of new experimental possibilities. An elegant formalism was built on the assumption of a hadron electromagnetic interaction based on the exchange of a virtual photon of four-momentum q{sup 2}. In this case FFs are analytic functions of only one variable, q{sup 2}, and the electromagnetic vertex γ{sup ∗}hh (h is any hadron) is defined by two structure functions, which, in turn, are expressed in terms of (2S+1) FFs, S being the hadron spin, assuming parity and time-invariance. Our aim is to anticipate the potentiality contained in the future data, combined with the present knowledge, to point out the relevant observables and the most significative measurements, and to give predictions to be compared to the data when they will be available.
Environmental impacts: Weathering factors, mechanism and forms affected the stone decaying in Petra
El-Gohary, M. A.
2017-11-01
The decay of stones in a natural environment is governed by extrinsic and intrinsic factors. Petra is exposed for centuries to the severe climatic conditions especially temperature (T), total monthly rainfall (TMR) and relative humidity (RH). In this regard, there are negative effects that result from these climatic elements on stone; which affect or are based on the chemical characteristics and physio-mechanical properties of the Petra rocks. The aim of this work is to determine the chemical and mineralogical characteristics including the morphological features which affect the behavior of stones in various environments using valuation techniques such as XRD, PM, Stereo M and SEM. The results proved that the stone was highly affected by two different deterioration mechanisms. The 1st one concerning physical mechanism and the 2nd one is regarding chemical deterioration. Both of them have led to some deterioration forms such as deep cracking, scaling, exfoliation and crumbling due mainly to the heating and cooling alternative cycles as well as frost action. In addition to salt crystallization and powder steadily off. It also show that most of the un-sheltered monuments were severely affected by the freezing and thawing actions, which is need to be a target in a special article to study their different effects. These activities in Petra are the subject of this study which also recommends the suitable materials and methods for preserving these valuable sites.
Pion vector form factor from lattice QCD at the physical point
Alexandrou, C.; Bacchio, S.; Dimopoulos, P.; Finkenrath, J.; Frezzotti, R.; Jansen, K.; Kostrzewa, B.; Mangin-Brinet, M.; Sanfilippo, F.; Simula, S.; Urbach, C.; Wenger, U.; ETM Collaboration
2018-01-01
We present an investigation of the electromagnetic pion form factor, Fπ(Q2) , at small values of the four-momentum transfer Q2 (≲0.25 GeV2), based on the gauge configurations generated by the European Twisted Mass Collaboration with Nf=2 twisted-mass quarks at maximal twist including a clover term. Momentum is injected using nonperiodic boundary conditions and the calculations are carried out at a fixed lattice spacing (a ≃0.09 fm ) and with pion masses equal to its physical value, 240 MeV and 340 MeV. Our data are successfully analyzed using chiral perturbation theory at next-to-leading order in the light-quark mass. For each pion mass two different lattice volumes are used to take care of finite size effects. Our final result for the squared charge radius is ⟨r2⟩π=0.443 (29 ) fm2, where the error includes several sources of systematic errors except the uncertainty related to discretization effects. The corresponding value of the SU(2) chiral low-energy constant ℓ¯6 is equal to ℓ¯6=16.2 (1.0 ).
Proton electromagnetic form factors: Basic notions, present achievements and future perspectives
Pacetti, Simone; Baldini Ferroli, Rinaldo; Tomasi-Gustafsson, Egle
2015-01-01
The aim of this report is to give basic notions on electromagnetic hadron form factors (FFs), as they are understood at the present time, to summarize and analyze the present experimental results and available theoretical models and to open a view on future perspectives. FFs are fundamental quantities, which describe the internal, dynamical structure of hadrons. Although the theoretical formalism was settled in the middle of last century, as well as the first experiments in electron-proton elastic scattering for which R. Hofstadter got the Nobel prize in 1961, a renewed activity is due to recent, surprising results and to the opening of new experimental possibilities. An elegant formalism was built on the assumption of a hadron electromagnetic interaction based on the exchange of a virtual photon of four-momentum q2. In this case FFs are analytic functions of only one variable, q2, and the electromagnetic vertex γ∗ hh (h is any hadron) is defined by two structure functions, which, in turn, are expressed in terms of (2 S + 1) FFs, S being the hadron spin, assuming parity and time-invariance. Our aim is to anticipate the potentiality contained in the future data, combined with the present knowledge, to point out the relevant observables and the most significative measurements, and to give predictions to be compared to the data when they will be available.
Proton electromagnetic form factors: Basic notions, present achievements and future perspectives
International Nuclear Information System (INIS)
Pacetti, Simone; Baldini Ferroli, Rinaldo; Tomasi-Gustafsson, Egle
2015-01-01
The aim of this report is to give basic notions on electromagnetic hadron form factors (FFs), as they are understood at the present time, to summarize and analyze the present experimental results and available theoretical models and to open a view on future perspectives. FFs are fundamental quantities, which describe the internal, dynamical structure of hadrons. Although the theoretical formalism was settled in the middle of last century, as well as the first experiments in electron–proton elastic scattering for which R. Hofstadter got the Nobel prize in 1961, a renewed activity is due to recent, surprising results and to the opening of new experimental possibilities. An elegant formalism was built on the assumption of a hadron electromagnetic interaction based on the exchange of a virtual photon of four-momentum q 2 . In this case FFs are analytic functions of only one variable, q 2 , and the electromagnetic vertex γ ∗ hh (h is any hadron) is defined by two structure functions, which, in turn, are expressed in terms of (2S+1) FFs, S being the hadron spin, assuming parity and time-invariance. Our aim is to anticipate the potentiality contained in the future data, combined with the present knowledge, to point out the relevant observables and the most significative measurements, and to give predictions to be compared to the data when they will be available
Hadronic form factor models and spectroscopy within the gauge/gravity correspondence
Energy Technology Data Exchange (ETDEWEB)
de Teramond, Guy F.; /Costa Rica U.; Brodsky, Stanley J.; /SLAC
2012-03-20
We show that the nonperturbative light-front dynamics of relativistic hadronic bound states has a dual semiclassical gravity description on a higher dimensional warped AdS space in the limit of zero quark masses. This mapping of AdS gravity theory to the boundary quantum field theory, quantized at fixed light-front time, allows one to establish a precise relation between holographic wave functions in AdS space and the light-front wavefunctions describing the internal structure of hadrons. The resulting AdS/QCD model gives a remarkably good accounting of the spectrum, elastic and transition form factors of the light-quark hadrons in terms of one parameter, the QCD gap scale. The light-front holographic approach described here thus provides a frame-independent first approximation to the light-front Hamiltonian problem for QCD. This article is based on lectures at the Niccolo Cabeo International School of Hadronic Physics, Ferrara, Italy, May 2011.
Directory of Open Access Journals (Sweden)
Christopher Terranova
Full Text Available Genetic studies have placed the Fgfr1 gene at the top of major ontogenic pathways that enable gastrulation, tissue development and organogenesis. Using genome-wide sequencing and loss and gain of function experiments the present investigation reveals a mechanism that underlies global and direct gene regulation by the nuclear form of FGFR1, ensuring that pluripotent Embryonic Stem Cells differentiate into Neuronal Cells in response to Retinoic Acid. Nuclear FGFR1, both alone and with its partner nuclear receptors RXR and Nur77, targets thousands of active genes and controls the expression of pluripotency, homeobox, neuronal and mesodermal genes. Nuclear FGFR1 targets genes in developmental pathways represented by Wnt/β-catenin, CREB, BMP, the cell cycle and cancer-related TP53 pathway, neuroectodermal and mesodermal programing networks, axonal growth and synaptic plasticity pathways. Nuclear FGFR1 targets the consensus sequences of transcription factors known to engage CREB-binding protein, a common coregulator of transcription and established binding partner of nuclear FGFR1. This investigation reveals the role of nuclear FGFR1 as a global genomic programmer of cell, neural and muscle development.
Extended vector meson dominance model for the baryon octet electromagnetic form factors
International Nuclear Information System (INIS)
Williams, R.A.; Puckett-Truman, C.
1996-01-01
An unresolved issue in the present understanding of nucleon structure is the effect of hidden strangeness on electromagnetic observables such as G n E (q 2 ). Previously, we have shown that G n E (q 2 ) is sensitive to small φNN couplings. A complementary approach for understanding effects due to strangeness content and the Okubo-Zweig-Iizuka (OZI) rule is to investigate the electromagnetic structure of hyperons. We apply Sakurai close-quote s universality limit of the SU(3) F symmetry relations and a prescription based on the OZI rule to calculate the electromagnetic form factors of the baryon octet states (p,n,Λ,Σ + ,Σ 0 ,Σ - ,Ξ 0 ,Ξ - ) within the framework of an extended vector meson dominance model. To provide additional motivation for experimental investigation, we discuss the possibility of extracting the ratio G M Λ (q 2 )/G M ΣΛ (q 2 ) from the Λ/Σ polarization ratio in kaon electroproduction experiments. copyright 1996 The American Physical Society
Covariant Spectator Theory of np scattering: Deuteron magnetic moment and form factors
Energy Technology Data Exchange (ETDEWEB)
Gross, Franz L. [JLAB
2014-06-01
The deuteron magnetic moment is calculated using two model wave functions obtained from 2007 high precision fits to $np$ scattering data. Included in the calculation are a new class of isoscalar $np$ interaction currents which are automatically generated by the nuclear force model used in these fits. After normalizing the wave functions, nearly identical predictions are obtained: model WJC-1, with larger relativistic P-state components, gives 0.863(2), while model WJC-2 with very small $P$-state components gives 0.864(2) These are about 1\\% larger than the measured value of the moment, 0.857 n.m., giving a new prediction for the size of the $\\rho\\pi\\gamma$ exchange, and other purely transverse interaction currents that are largely unconstrained by the nuclear dynamics. The physical significance of these results is discussed, and general formulae for the deuteron form factors, expressed in terms of deuteron wave functions and a new class of interaction current wave functions, are given.
Terranova, Christopher; Narla, Sridhar T; Lee, Yu-Wei; Bard, Jonathan; Parikh, Abhirath; Stachowiak, Ewa K; Tzanakakis, Emmanuel S; Buck, Michael J; Birkaya, Barbara; Stachowiak, Michal K
2015-01-01
Genetic studies have placed the Fgfr1 gene at the top of major ontogenic pathways that enable gastrulation, tissue development and organogenesis. Using genome-wide sequencing and loss and gain of function experiments the present investigation reveals a mechanism that underlies global and direct gene regulation by the nuclear form of FGFR1, ensuring that pluripotent Embryonic Stem Cells differentiate into Neuronal Cells in response to Retinoic Acid. Nuclear FGFR1, both alone and with its partner nuclear receptors RXR and Nur77, targets thousands of active genes and controls the expression of pluripotency, homeobox, neuronal and mesodermal genes. Nuclear FGFR1 targets genes in developmental pathways represented by Wnt/β-catenin, CREB, BMP, the cell cycle and cancer-related TP53 pathway, neuroectodermal and mesodermal programing networks, axonal growth and synaptic plasticity pathways. Nuclear FGFR1 targets the consensus sequences of transcription factors known to engage CREB-binding protein, a common coregulator of transcription and established binding partner of nuclear FGFR1. This investigation reveals the role of nuclear FGFR1 as a global genomic programmer of cell, neural and muscle development.
Energy Technology Data Exchange (ETDEWEB)
Radyushkin, Anatoly V. [ODU, JLAB
2014-07-01
We outline basics of a new approach to transverse momentum dependence in hard processes. As an illustration, we consider hard exclusive transition process gamma*gamma -> to pi^0 at the handbag level. Our starting point is coordinate representation for matrix elements of operators (in the simplest case, bilocal O(0,z)) describing a hadron with momentum p. Treated as functions of (pz) and z^2, they are parametrized through a virtuality distribution amplitude (VDA) Phi (x, sigma), with x being Fourier-conjugate to (pz) and sigma Laplace-conjugate to z^2. For intervals with z^+=0, we introduce transverse momentum distribution amplitude (TMDA) Psi (x, k_\\perp), and write it in terms of VDA Phi (x, \\sigma). The results of covariant calculations, written in terms of Phi (x sigma) are converted into expressions involving Psi (x, k_\\perp. Starting with scalar toy models, we extend the analysis onto the case of spin-1/2 quarks and QCD. We propose simple models for soft VDAs/TMDAs, and use them for comparison of handbag results with experimental (BaBar and BELLE) data on the pion transition form factor. We also discuss how one can generate high-k_\\perp tails from primordial soft distributions.
Free-Form Rapid Prototyped Porous PDMS Scaffolds Incorporating Growth Factors Promote Chondrogenesis
Directory of Open Access Journals (Sweden)
Andrés Díaz Lantada
2014-01-01
Full Text Available In this study, we present a promising approach for the rapid development of porous polydimethylsiloxane (PDMS scaffold prototypes, with outer geometry defined from the design stage, according to the form of conventional implants or adapted to patients’ biostructures. The manufacture method is based on phase separation processes using materials obtained by casting within additive rapid prototyped molds. We include a comparative study of PDMS sponges obtained by different simple processes. Final in vitro assessment is carried out using hMSCs (bone marrow-derived human mesenchymal stem cells, cultured onto porous PDMS scaffolds functionalized with aminopropyltriethoxysilane (APTS and equilibrated with a trophic factors medium produced by the cells. Results show that porous PDMS scaffold prototypes are excellent 3D platforms for hMSCs adhesion. Furthermore, this PDMS-3D niche, seeded with hMSCs and chondrogenic incubation medium during three weeks, showed a successful chondrogenesis determined by collagen type II expression. Thus, results show a versatile method to produce a 3D niche to address questions about cartilage and endochondral bone formation or skeleton tissues clinical approaches.
Trojanek, Pavel; Prochazka, Ivan; Blazej, Josef
2017-05-01
We are reporting on timing parameters of commonly used standard Small Form Factor Pluggable (SFP) laser modules using single photon counting method. Photon counting is a promising approach for laser time transfer via optical fiber communication hardware. The sub-picosecond precision and stability may be achieved. We have performed several experiments with the aim to measure main parameters of the modules, such as time delay precision, time stability and temperature stability, all being critical for optical time transfer applications. Two standard 16 and 10 Gbit/s at 850 nm SFP modules were examined. The ultimate precision of possible time transfer of 800 fs for averaging times of hours was achieved. The modules together with their driving circuits exhibited very good temperature stability. The temperature drift as low as 300+/-200 fs/K was measured. The achieved timing parameters will enable to use the standard SFP modules for a new method of two way time transfer where the time differences between two distant time scales are measured in parallel to data transfer on existing optical data links without any communication interference.
Energy Technology Data Exchange (ETDEWEB)
Gueven, H.M. (San Diego State Univ., CA (United States). Dept. of Mechanical Engineering)
1994-08-01
In this paper, a closed-form expression for intercept factor is used to carry out the optimization of parabolic trough collector geometry (rim angle and concentration ratio). It is shown that the presented closed-form expression eliminates the need for a detailed ray-trace computer code and facilitates optimization of the collector optical design parameters.
Test of critical heat flux with non-uniform axial power shapes in rectangle narrow channel
International Nuclear Information System (INIS)
Xiong Wanyu; Wang Fei; Xiao Zejun; Lu Donghua
2007-01-01
Critical heat flux for axial non-uniform heat flux distribution in rectangle narrow channel was studied in this report. During the test, electric heating were adopted, and the axial direction power loaded were truncation cosine distribution. The de-ionized water was heated. The test result indicated that CHF with non-uniform axial heat flux distribution was lower than CHF with uniform axial heat flux distribution. A correction factor was used to analyze the test data. The semi-empirical relation of correction factor of CHF with axial non-uniform heat flux distribution had been obtained. Comparing to the existing correction factor models, it revealed that the proposed semi-empirical relation predictive CHF with axial non-uniform heat flux distribution in rectangle narrow channel was most accurate. (authors)
Energy Technology Data Exchange (ETDEWEB)
Lin, Dexu; Nasher Ahmed, Samer Ali; Rosner, Christoph [Helmholtz-Institut Mainz (Germany); Mainz Univ. (Germany); Dbeyssi, Alaa; Larin, Paul; Morales, Cristina; Wang, Yadi [Helmholtz-Institut Mainz (Germany); Maas, Frank [Helmholtz-Institut Mainz (Germany); Mainz Univ. (Germany); PRISMA Cluster of Excellence, Johannes Gutenberg Universitaet Mainz (Germany); Collaboration: BESIII-Collaboration
2016-07-01
The structure of the proton can be understood through the study of its electromagnetic (EM) form factors. Electron scattering experiments (space-like region) have explored the proton EM form factors with a high accuracy. Only few data on the proton form factors in the time-like region, and only a very coarse determination of the individual electric and magnetic form factors (or their ratio) has been possible so far. The BESIII (Beijing Spectrometer III) at BEPCII (Beijing Electron Positron Collider II) has collected large data samples from J/ψ-mass up to 4.60 GeV. These data can be used to measure proton EM form factors by means of Initial-State-Radiation (ISR) events with the process e{sup +}e{sup -} → p anti pγ{sub ISR}. With 7.408 fb{sup -1} total luminosity of seven data samples from 3.773-4.600 GeV, the proton form factors and the cross section of p anti p have been analyzed with ISR-tagged method. In this talk, the status of this work is reported together with a discussion of the analysis of the background.
Experimental Investigations on Axially and Eccentrically Loaded Masonry Walls
Keshava, Mangala; Raghunath, Seshagiri Rao
2017-12-01
In India, un-reinforced masonry walls are often used as main structural components in load bearing structures. Indian code on masonry accounts the reduction in strength of walls by using stress reduction factors in its design philosophy. This code was introduced in 1987 and reaffirmed in 1995. The present study investigates the use of these factors for south Indian masonry. Also, with the gaining popularity in block work construction, the aim of this study was to find out the suitability of these factors given in the Indian code to block work masonry. Normally, the load carrying capacity of masonry walls can be assessed in three ways, namely, (1) tests on masonry constituents, (2) tests on masonry prisms and (3) tests on full-scale wall specimens. Tests on bricks/blocks, cement-sand mortar, brick/block masonry prisms and 14 full-scale brick/block masonry walls formed the experimental investigation. The behavior of the walls was investigated under varying slenderness and eccentricity ratios. Hollow concrete blocks normally used as in-fill masonry can be considered as load bearing elements as its load carrying capacity was found to be high when compared to conventional brick masonry. Higher slenderness and eccentricity ratios drastically reduced the strength capacity of south Indian brick masonry walls. The reduction in strength due to slenderness and eccentricity is presented in the form of stress reduction factors in the Indian code. These factors obtained through experiments on eccentrically loaded brick masonry walls was lower while that of brick/block masonry under axial loads was higher than the values indicated in the Indian code. Also the reduction in strength is different for brick and block work masonry thus indicating the need for separate stress reduction factors for these two masonry materials.
Glintborg, Bente; Sørensen, Inge J; Østergaard, Mikkel; Dreyer, Lene; Mohamoud, Abdiweli A; Krogh, Niels S; Hendricks, Oliver; Andersen, Lis S; Raun, Johnny L; Kowalski, Marcin R; Danielsen, Laura; Pelck, Randi; Nordin, Henrik; Pedersen, Jens K; Kraus, Dorte G A; Christensen, Susan R; Hansen, Inger M J; Esbesen, Jakob; Schlemmer, Annette; Loft, Anne G; Al Chaer, Nabil; Salomonsen, Lone; Hetland, Merete L
2017-01-01
To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders (e.g., HLA-B27 status). Observational cohort study based on prospectively registered data in the nationwide DANBIO registry. We used Kaplan-Meier plots, Cox, and logistic regression analyses to study the effect of diagnosis (nr-axSpA vs AS) and potential confounders (sex/age/start yr/HLA-B27/disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm]. The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients with nr-axSpA were more frequently women (50%/27%) and HLA-B27-negative (85/338 = 25%), compared to AS (81/476 = 17%; p 0.05). Response rates were similar in AS and nr-axSpA (p > 0.05). HLA-B27 negativity was associated with poorer treatment adherence [HLA-B27 negative/positive, nr-axSpA: HR 1.74 (1.29-2.36), AS: HR 2.04 (1.53-2.71), both p < 0.0001]; and lower response rates (nr-axSpA: 18/61 = 30% vs 93/168 = 55%; AS: 17/59 = 29% vs 157/291 = 54%, both p < 0.05). In this nationwide cohort, patients with nr-axSpA had higher subjective disease activity at start of first TNFi treatment, but similar outcomes to patients with AS after confounder adjustment. HLA-B27 positivity was associated with better outcomes irrespective of axSpA subdiagnosis.
Effect of different tillage intensity on yields and yield-forming factors in winter wheat
Directory of Open Access Journals (Sweden)
Martin Houšť
2012-01-01
Full Text Available The paper presents results of a study on application of minimum tillage technologies when growing winter wheat. Experiments were performed in the sugar-beet-growing region with loamy chernozem within the period of 2005–2009. Aanalysed and evaluated were effects of different methods of soil processing on yield-forming factors in stands of winter wheat grown after three different preceding crops (i.e. alfalfa, maize for silage and pea. Evaluated were the following four variants of tillage: (1 conventional ploughing to the depth of 0.22 m (Variant 1; (2 ploughing to the depth of 0.15 m (Variant 2; (3 direct sowing into the untilled soil (Variant 3, and (4 shallow tillage to the depth of 0.10 m (Variant 4.The effect of different tillage intensity on winter wheat yields was statistically non-significant after all forecrops. After alfalfa, the highest and the lowest average yields were recorded in Variant 2 (i.e. with ploughing to the depth of 0.15 m and Variant 3 (direct sowing into the untilled soil, respectively. After maize grown for silage, higher yields were obtained in Variant 2 and Variant 1 (conventional ploughing while in Variants 4 and 3 the obtained yields were lower. When growing winter wheat after pea as a preceding crop, the highest and the lowest average yields were recorded after direct sowing (Variant 3 and in Variant 1 (i.e. ploughing to the depth of 0.22 m, respectively. Results of studies on effect of different tillage technologies on yields of winter wheat crops indicate that under the given pedological and climatic conditions it is possible to apply methods of reduced tillage intensity. However, the choice of the corresponding technology must be performed with regard to the type of preceding crop.
N → Δ (1232) electromagnetic transition form factor and pion-nucleon dynamics at moderate energies
International Nuclear Information System (INIS)
Jurewicz, A.
1980-01-01
The dependence of the electromagnetic N → Δ (1232) transition form factor G/sup asterisk//sub M/(q 2 ) on q 2 , the four-momentum transfer squared, has been calculated with the use of relativistic dispersion relations supplemented with some dynamical assumptions. In the first place, they regard the phase of the magnetic dipole amplitude of electroproduction of pions on nucleons in the p 33 final state beyond the region of elastic unitarity. Namely, over the range from the lowest inelastic threshold up to 1780 MeV pion-nucleon c.m. energy, the phase in question has been identified with the real part of the respective phase shift of pion-nucleon scattering. Secondly, contributions to the dispersion integral from the higher energy region have been neglected. Finally, the polynomial ambiguity which appears in the problem has been fixed by requiring that the foregoing amplitude of electroproduction vanishes, independently of q 2 , at the upper end of the integration interval as defined above. These assumptions which preserve unitarity were shown previously to lead to very good results when applied to the calculation of the multipole amplitudes M/sup() 3/2/ 1 /sub +/ and E/sup() 3/2/ 1 /sub +/ of photopion production on nucleons in the Δ (1232) region. Now it is also shown that G/sup asterisk//sub M/(q 2 ) calculated in that fashion follows remarkably well the data over the whole range 0 2 2 currently covered by quantitative experimental studies. Some speculation concerning a possible dynamical rooting of the foregoing assumptions is presented
Axial magnetic field produced by axially and radially magnetized permanent rings
International Nuclear Information System (INIS)
Peng, Q.L.; McMurry, S.M.; Coey, J.M.D.
2004-01-01
Axial magnetic fields produced by axially and radially magnetized permanent magnet rings were studied. First, the axial magnetic field produced by a current loop is introduced, from which the axial field generated by an infinitely thin solenoid and by an infinitely thin current disk can be derived. Then the axial fields produced by axially and by radially magnetized permanent magnet rings can be obtained. An analytic formula for the axial fields produced by two axially magnetized rings is given. A permanent magnet with a high axial gradient field is fabricated, the measured results agree with the theoretical calculation very well. As an example, the axial periodic field produced by an arrangement of alternating axially and radially magnetized rings has been discussed
View of the Axial Field Spectrometer
1980-01-01
The Axial Field Spectrometer, with the vertical uranium/scintillator calorimeter and the central drift chamber retracted for service. One coil of the Open Axial Field Magnet is just visible to the right.
International Nuclear Information System (INIS)
Weisiger, R.A.; Mendel, C.M.; Cavalieri, R.R.
1986-01-01
Two general models have been proposed for predicting the effects of metabolism, protein binding, and plasma flow on the removal of drugs by the liver. These models differ in the degree of plasma mixing assumed to exist within each hepatic sinusoid. The venous equilibrium model treats the sinusoid as a single well-stirred compartment, whereas the sinusoidal model effectively breaks up the sinusoid into a large number of sequentially perfused compartments which do not exchange their contents except through plasma flow. As a consequence, the sinusoidal model, but not the venous equilibrium model, predicts that the concentration of highly extracted drugs will decline as the plasma flows through the hepatic lobule. To determine which of these alternative models best describes the hepatic uptake process, we looked for evidence that concentration gradients are formed during the uptake of [ 125 I]thyroxine by the perfused rat liver. Autoradiography of tissue slices after perfusion of the portal vein at physiologic flow rates with protein-free buffer containing [ 125 I]thyroxine demonstrated a rapid exponential fall in grain density with distance from the portal venule, declining by half for each 8% of the mean length of the sinusoid. Reversing the direction of perfusate flow reversed the direction of the autoradiographic gradients, indicating that they primarily reflect differences in the concentration of thyroxine within the hepatic sinusoids rather than differences in the uptake capacity of portal and central hepatocytes. Analysis of the data using models in which each sinusoid was represented by different numbers of sequentially perfused compartments (1-20) indicated that at least eight compartments were necessary to account for the magnitude of the gradients seen
2011-05-13
... Factor-Diphtheria Toxoid Conjugate AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. [[Page... veterinary prescription use of gonadotropin releasing factor-diphtheria toxoid conjugate by subcutaneous... provides for the veterinary prescription use of IMPROVEST (gonadotropin releasing factor-diphtheria toxoid...
Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.E.; Hink, M.A.; Limpens, E.H.M.; Gadella, T.W.J.; Bisseling, T.
2014-01-01
Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It
Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.; Hink, M.A.; Limpens, E.; Gadella, T.W.J.; Bisseling, T.
2014-01-01
Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It
Chiral behavior of K →π l ν decay form factors in lattice QCD with exact chiral symmetry
Aoki, S.; Cossu, G.; Feng, X.; Fukaya, H.; Hashimoto, S.; Kaneko, T.; Noaki, J.; Onogi, T.; Jlqcd Collaboration
2017-08-01
We calculate the form factors of the K →π l ν semileptonic decays in three-flavor lattice QCD and study their chiral behavior as a function of the momentum transfer and the Nambu-Goldstone boson masses. Chiral symmetry is exactly preserved by using the overlap quark action, which enables us to directly compare the lattice data with chiral perturbation theory (ChPT). We generate gauge ensembles at a lattice spacing of 0.11 fm with four pion masses covering 290-540 MeV and a strange quark mass ms close to its physical value. By using the all-to-all quark propagator, we calculate the vector and scalar form factors with high precision. Their dependence on ms and the momentum transfer is studied by using the reweighting technique and the twisted boundary conditions for the quark fields. We compare the results for the semileptonic form factors with ChPT at next-to-next-to-leading order in detail. While many low-energy constants appear at this order, we make use of our data of the light meson electromagnetic form factors in order to control the chiral extrapolation. We determine the normalization of the form factors as f+(0 )=0.9636 (36 )(-35+57) and observe reasonable agreement of their shape with experiment.
Factor Structure of the BASC-2 Behavioral and Emotional Screening System Student Form
Dowdy, Erin; Twyford, Jennifer M.; Chin, Jenna K.; DiStefano, Christine A.; Kamphaus, Randy W.; Mays, Kristen L.
2011-01-01
The BASC-2 Behavioral and Emotional Screening System (BESS) Student Form (Kamphaus & Reynolds, 2007) is a recently developed youth self-report rating scale designed to identify students at risk for behavioral and emotional problems. The BESS Student Form was derived from the Behavior Assessment System for Children-Second Edition Self-Report of…
Modeling the axial offset anomaly in PWRs
Energy Technology Data Exchange (ETDEWEB)
Blok, J.; Chauffriat, S.; Frattini, P. [EPRI, Palo Alto, CA (United States)
2002-07-01
Axially un-symmetrical flux depression is defined as axial offset anomaly (AOA) in PWRs. The effect has only been observed in PWR reactor cores operated at high power duty. The threat of AOA limits the aggressiveness of core design, and in extreme form, the effect can decrease shutdown margin near end of cycle (EOC) sufficiently to mandate power reduction. AOA is ultimately the result of boron hideout on fuel. Studies have confirmed that sufficient boron hideout to produce measurable AOA requires relatively large amounts of corrosion products to deposit on the fuel. Because corrosion product deposition is favored in the boiling upper regions of the (high duty) core, the amount of boron uptake in these regions is large in proportion, and core reactivity is affected disproportionately in the upper region of the core. This paper explores possible mechanisms for deposition of corrosion products on fuel and the consequent incorporation of boron compounds. The proposed mechanisms are viewed in the context of corrosion product samples from the Callaway Cycle 9, one of the PWR fuel cycles that exhibited the most severe AOA to date. (author)
Similarity of urinary risk factors among stone-forming patients in five regions of the United States
Harvey, J. A.; Hill, K. D.; Pak, C. Y.
1990-01-01
Study Objective: To compare urinary biochemical risk factors among stone-forming patients in the Southeast (SE) or "stone belt" versus four other regions of the United States. Design: Prospective biochemical survey for regional comparisons. Setting: Referral-based nephrolithiasis clinics, urologists, nephrologists, and family practitioners. Patients: Consecutive sample of 3473 stone-forming patients who submitted 24-hour urine collections for biochemical analyses of stone-forming risk factors. Interventions: None. Subjects taking medication known to interfere with stone-forming risk factors were deleted from the final data compilation. Measurements and Main Results: Overall, the mean values for each urinary parameter spanned a narrow range without significant difference between the five regions. Among "metabolic" factors, 40% in the SE had hypercalciuria (> 6.25 mmol/d), compared to 35%-43% in other regions, and hyperuricosuria (> 4.2 mmol/d) was found in 16% in the SE versus 17%-19% elsewhere. Among "environmental" factors, low urine volume ( magnesium. Conclusions: Despite expected regional differences in nutritional and environmental influences, the results of this study showed a striking similarity in urinary biochemical risk factor profiles of stone-formers in all five regions of the United States.
Diagonal form factors and hexagon form factors
International Nuclear Information System (INIS)
Jiang, Yunfeng; Petrovskii, Andrei
2016-01-01
We study the heavy-heavy-light (HHL) three-point functions in the planar N=4 super-Yang-Mills theory using the recently proposed hexagon bootstrap program http://arxiv.org/abs/1505.06745. We prove the conjecture of Bajnok, Janik and Wereszczynski http://dx.doi.org/10.1007/JHEP09(2014)050 on the polynomial L-dependence of HHL structure constant up to the leading finite-size corrections, where L is the length of the heavy operators. The proof is presented for a specific set-up but the method can be applied to more general situations.
Higgs amplitudes from supersymmetric form factors Part II: $\\mathcal{N}<4$ super Yang-Mills arXiv
Brandhuber, Andreas; Penante, Brenda; Travaglini, Gabriele
The study of form factors has many phenomenologically interesting applications, one of which is Higgs plus gluon amplitudes in QCD. Through effective field theory techniques these are related to form factors of various operators of increasing classical dimension. In this paper we extend our analysis of the first finite top-mass correction, arising from the operator ${\\rm Tr} (F^3)$, from $\\mathcal{N}=4$ super Yang-Mills to theories with $\\mathcal{N}<4$, for the case of three gluons and up to two loops. We confirm our earlier result that the maximally transcendental part of the associated Catani remainder is universal and equal to that of the form factor of a protected trilinear operator in the maximally supersymmetric theory. The terms with lower transcendentality deviate from the $\\mathcal{N}=4$ answer by a surprisingly small set of terms involving for example $\\zeta_2$, $\\zeta_3$ and simple powers of logarithms, for which we provide explicit expressions.
SCP2, a major protein component of the axial elements of synaptonemal complexes
Schalk, J.A.C.
1999-01-01
Synaptonemal complexes (SCs) are ladderlike protein structures, which are formed between homologous chromosomes during the prophase of the first meiotic division. SCs consist of two axial elements, one along each chromosome, and transverse filaments (TFs), which connect the axial elements.
"Legal aspects of forms and factors of mobbing in the Republic of Macedonia"
Sotiroski, Ljupco
2010-01-01
This project represents a serious attempt for discovering and presenting the meaning and the role of mobbing as a new contemporary concept in Macedonia in the last 3-4 years. Mobbing is commonly defined as repeated, non-physical harassment in the workplace in certain period, which aims to humiliate and belittle the employee. The forms of mobbing that have been occurring in the global and European practice commonly refer to psycho-physical harassment of the employee, various forms of sexua...
On determinant representations of scalar products and form factors in the SoV approach: the XXX case
Kitanine, N.; Maillet, J. M.; Niccoli, G.; Terras, V.
2016-03-01
In the present article we study the form factors of quantum integrable lattice models solvable by the separation of variables (SoVs) method. It was recently shown that these models admit universal determinant representations for the scalar products of the so-called separate states (a class which includes in particular all the eigenstates of the transfer matrix). These results permit to obtain simple expressions for the matrix elements of local operators (form factors). However, these representations have been obtained up to now only for the completely inhomogeneous versions of the lattice models considered. In this article we give a simple algebraic procedure to rewrite the scalar products (and hence the form factors) for the SoV related models as Izergin or Slavnov type determinants. This new form leads to simple expressions for the form factors in the homogeneous and thermodynamic limits. To make the presentation of our method clear, we have chosen to explain it first for the simple case of the XXX Heisenberg chain with anti-periodic boundary conditions. We would nevertheless like to stress that the approach presented in this article applies as well to a wide range of models solved in the SoV framework.
On determinant representations of scalar products and form factors in the SoV approach: the XXX case
International Nuclear Information System (INIS)
Kitanine, N; Maillet, J M; Niccoli, G; Terras, V
2016-01-01
In the present article we study the form factors of quantum integrable lattice models solvable by the separation of variables (SoVs) method. It was recently shown that these models admit universal determinant representations for the scalar products of the so-called separate states (a class which includes in particular all the eigenstates of the transfer matrix). These results permit to obtain simple expressions for the matrix elements of local operators (form factors). However, these representations have been obtained up to now only for the completely inhomogeneous versions of the lattice models considered. In this article we give a simple algebraic procedure to rewrite the scalar products (and hence the form factors) for the SoV related models as Izergin or Slavnov type determinants. This new form leads to simple expressions for the form factors in the homogeneous and thermodynamic limits. To make the presentation of our method clear, we have chosen to explain it first for the simple case of the XXX Heisenberg chain with anti-periodic boundary conditions. We would nevertheless like to stress that the approach presented in this article applies as well to a wide range of models solved in the SoV framework. (paper)
Thermocapillary Convection in Floating Zone with Axial Magnetic Fields
Liang, Ruquan; Yang, Shuo; Li, Jizhao
2014-02-01
Numerical simulations on the effects of axial magnetic fields on the thermocapillary convection in a liquid bridge of silicone-oil-based ferrofluid under zero gravity have been conducted. The Navier-Stokes equations coupled with the energy conservation equation are solved on a staggered grid, and the mass conserving level set approach is used to capture the free surface deformation of the liquid bridge. The obvious effects of the magnetic fields on the flow pattern as well as the velocity and temperature distributions in the liquid bridge can be detected. The axial magnetic fields suppress the thermocapillary convection and a stagnant flow zone is formed between the circulating flow and the symmetric axis as the magnetic fields increase. The axial magnetic fields affect not only the velocity level inside the liquid bridge but also the velocity level on the free surface. The temperature contours near the free surface illustrates conduction-type temperature profiles at moderate strength fields.
Measurement of the Proton's Electric to Magnetic Form Factor Ratio from 1H-vector(e-vector,e'p)
International Nuclear Information System (INIS)
Crawford, C. B.; Akdogan, T.; Bertozzi, W.; Botto, T.; Clasie, B.; DeGrush, A.; Donnelly, T. W.; Dow, K.; Farkhondeh, M.; Fatemi, R.; Franklin, W.; Gilad, S.; Hasell, D.; Kohl, M.; Kolster, H.; Maschinot, A.; Matthews, J.; Meitanis, N.; Milner, R. G.; Redwine, R. P.
2007-01-01
We report the first precision measurement of the proton electric to magnetic form factor ratio from spin-dependent elastic scattering of longitudinally polarized electrons from a polarized hydrogen internal gas target. The measurement was performed at the MIT-Bates South Hall Ring over a range of four-momentum transfer squared Q 2 from 0.15 to 0.65 (GeV/c) 2 . Significantly improved results on the proton electric and magnetic form factors are obtained in combination with existing cross-section data on elastic electron-proton scattering in the same Q 2 region
International Nuclear Information System (INIS)
Mukherjee, G.; Sharma, S.K.
1984-03-01
A microscopic description of the recent data on the Coulomb form factors for the Osub(gnd) + →2 2 + transitions in the nuclei 48 Ti and 50 Cr is attempted in terms of the prolate and oblate intrinsic states resulting from realistic effective interactions operating in the 2p-1f shell. The results for the higher momentum-transfer region show dramatic improvements compared to the form factor estimates obtained in some recent shell model calculations involving the fsub(7/2)sup(n)+fsub(7/2)sup(n-1)psub(3/2) configurations. (author)
Measurements of the Proton Elastic-Form-Factor Ratio μpGEp/GMp at Low Momentum Transfer
International Nuclear Information System (INIS)
Ron, G.; Piasetzky, E.; Pomerantz, I.; Shneor, R.; Glister, J.; Lee, B.; Choi, Seonho; Kang, H.; Oh, Y.; Song, J.; Yan, X.; Allada, K.; Dutta, C.; Armstrong, W.; Meziani, Z.-E.; Yao, H.; Arrington, J.; Solvignon, P.; Beck, A.; May-Tal Beck, S.
2007-01-01
High-precision measurements of the proton elastic form-factor ratio, μ p G E p /G M p , have been made at four-momentum transfer, Q 2 , values between 0.2 and 0.5 GeV 2 . The new data, while consistent with previous results, clearly show a ratio less than unity and significant differences from the central values of several recent phenomenological fits. By combining the new form-factor ratio data with an existing cross-section measurement, one finds that in this Q 2 range the deviation from unity is primarily due to G E p being smaller than expected
Wilkins, Natalie; Myers, Lindsey; Kuehl, Tomei; Bauman, Alice; Hertz, Marci
2018-01-01
Violence takes many forms, including intimate partner violence, sexual violence, child abuse and neglect, bullying, suicidal behavior, and elder abuse and neglect. These forms of violence are interconnected and often share the same root causes. They can also co-occur together in families and communities and can happen at the same time or at different stages of life. Often, due to a variety of factors, separate, “siloed” approaches are used to address each form of violence. However, understanding and implementing approaches that prevent and address the overlapping root causes of violence (risk factors) and promote factors that increase the resilience of people and communities (protective factors) can help practitioners more effectively and efficiently use limited resources to prevent multiple forms of violence and save lives. This article presents approaches used by 2 state health departments, the Maryland Department of Health and Mental Hygiene and the Colorado Department of Public Health and Environment, to integrate a shared risk and protective factor approach into their violence prevention work and identifies key lessons learned that may serve to inform crosscutting violence prevention efforts in other states. PMID:29189502
Axial Lengths in Children with Recessive Cornea Plana.
Al Hazimi, Amro; Khan, Arif O
2015-06-01
While flat keratometry contributes to the hyperopia and associated refractive accommodative esotropia that is part of recessive cornea plana, whether or not axial lengths are abnormally short in the disease is unclear. In this study we assess this possibility. Prospective (2010-2012) axial length measurement (IOLmaster; Carl Zeiss, Oberkochen, Germany) of affected right eyes and comparison to right eyes with refractive accommodative esotropia only. Keratometry and refraction were also performed. For eight affected right eyes (age 10-12 years; seven families) axial length ranged from 21.46-24.80 mm (mean 23.34). Best corrected visual acuity ranged from 20/25 to 20/50, keratometry from 25.33-39.80 diopters (D) [mean 31.80], and refraction from +2.00 to +14.00 D (mean +7.22). For 50 control right eyes (age 4-12 years), axial length ranged from 19.87-23.66 mm (mean 21.6). Best-corrected visual acuity was 20/25 or better, keratometry ranged from 39.81-46.25 D (mean 42.42), and refraction from +2.25 to +8.00 D (mean 4.71). Axial lengths were longer in the affected group (2-tailed unpaired t-test p value 0.000005) despite greater hyperopia (2-tailed unpaired t-test p value 0.001). Despite greater hyperopia, axial lengths were longer in eyes with recessive cornea plana, evidence that axial lengths are not shortened by the disease. Keratometry in children with cornea plana was below the range of controls and was the major factor underlying the phenotype's hyperopia.
International Nuclear Information System (INIS)
Arrington, John; Sick, Ingo
2007-01-01
The extraction of the strangeness form factors from parity-violating elastic electron-proton scattering is sensitive to the electromagnetic form factors at low Q 2 . We provide parametrizations for the form factors and uncertainties, including the effects of two-photon exchange corrections to the extracted electromagnetic form factors. We study effect of the correlations between different form factors, in particular as they impact the parity-violating asymmetry and the extraction of the strangeness form factors. We provide a prescription to extract the strangeness form factors from the asymmetry that provides an excellent approximation of the full two-photon correction. The corrected form factors are also appropriate as input for other low-Q analyses, although the effects of correlations and two-photon exchange corrections may be different
Directory of Open Access Journals (Sweden)
E E Shults
2017-12-01
Full Text Available The article considers reasons for radical mass forms of social protest in the context of the ‘Malthusian trap’ and structural-demographic theory of Jack Goldstone, which have become popular in the last two decades. The author critically evaluates these two conceptions and comes to the conclusion that the principles they underline are just concomitant factors, i.e. additional risk factors for political systems and regimes, rather than causes of radical mass forms of social protest. The author suggests a method of analysis that consists of studying the circumstances, i.e. the wide historical context, in which mass forms of social protest usually emerge, and provides a large number of illustrative examples. The scientific approach to the identification of social-historical determinants of radical forms of social protest implies that if something is a reason/cause of an event, then this reason/cause must be present whenever there is such an event both alone or within a complex of concomitant factors. The ‘Malthusian trap’ and demographic factors cannot be traced in all manifestations of radical mass forms of social protest in modern and contemporary history. Moreover, the ‘Malthusian trap’ and demographic pressure on the economy and social system do not always lead to mass forms of social protest. The wave of radical forms of social protest in the last decade, i.e. the so-called ‘color revolutions’, ‘Arab spring’, protest actions in France, England and the USA, once again confirms the relevance of the author’s approach and the importance of critical study of the traditional conceptions.
Modelling the cardiac transverse-axial tubular system
Czech Academy of Sciences Publication Activity Database
Pásek, Michal; Šimurda, J.; Christé, G.; Orchard, C.
2008-01-01
Roč. 96, - (2008), s. 226-246 ISSN 0079-6107 Institutional research plan: CEZ:AV0Z20760514 Keywords : cardiac cell * transverse-axial tubular system * quantitative modelling Subject RIV: BO - Biophysics Impact factor: 6.388, year: 2008
Amphiregulin Antibody and Reduction of Axial Elongation in Experimental Myopia
Directory of Open Access Journals (Sweden)
Wen Jun Jiang
2017-03-01
Full Text Available To examine the mechanism of ocular axial elongation in myopia, guinea pigs (age: 2–3 weeks which either underwent unilateral or bilateral lens-induced myopization (group 1 or which were primarily myopic at baseline (group 2 received unilateral intraocular injections of amphiregulin antibody (doses: 5, 10, or 15 μg three times in intervals of 9 days. A third group of emmetropic guinea pigs got intraocular unilateral injections of amphiregulin (doses: 0.25, 0.50 or 1.00 ng, respectively. In each group, the contralateral eyes received intraocular injections of Ringer's solution. In intra-animal inter-eye comparison and intra-eye follow-up comparison in groups 1 and 2, the study eyes as compared to the contralateral eyes showed a dose-dependent reduction in axial elongation. In group 3, study eyes and control eyes did not differ significantly in axial elongation. Immunohistochemistry revealed amphiregulin labelling at the retinal pigment epithelium in eyes with lens-induced myopization and Ringer's solution injection, but not in eyes with amphiregulin antibody injection. Intraocular injections of amphiregulin-antibody led to a reduction of lens-induced axial myopic elongation and of the physiological eye enlargement in young guinea pigs. In contrast, intraocularly injected amphiregulin in a dose of ≤1 ng did not show a significant effect. Amphiregulin may be one of several essential molecular factors for axial elongation.
Czech Academy of Sciences Publication Activity Database
Jonák, Jiří
2007-01-01
Roč. 849, 1-2 (2007), s. 141-153 ISSN 1570-0232 R&D Projects: GA AV ČR IAA5052206; GA AV ČR KJB500520503; GA MŠk 2B06065 Institutional research plan: CEZ:AV0Z50520514 Keywords : bacterial elongation factors EF-Tu, , G-domain * recombinant EF-Tus * preparation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.935, year: 2007
Huwe, Le W; Sullan, Gurdeep K; Hu, Jerry C; Athanasiou, Kyriacos A
2018-03-01
Generating neocartilage with suitable mechanical integrity from a cell source that can circumvent chondrocyte scarcity is indispensable for articular cartilage regeneration strategies. Costal chondrocytes of the rib eliminate donor site morbidity in the articular joint, but it remains unclear how neocartilage formed from these cells responds to mechanical loading, especially if the intent is to use it in a load-bearing joint. In a series of three experiments, this study sought to determine efficacious parameters of passive axial compressive stimulation that would enable costal chondrocytes to synthesize mechanically robust cartilage. Experiment 1 determined a suitable time window for stimulation by its application during either the matrix synthesis phase, the maturation phase, or during both phases of the self-assembling process. The results showed that compressive stimulation at either time was effective in increasing instantaneous moduli by 92% and 87% in the synthesis and maturation phases, respectively. Compressive stimulation during both phases did not further improve properties beyond a one-time stimulation. The magnitude of passive axial compression was examined in Experiment 2 by applying 0, 3.3, 5.0, or 6.7 kPa stresses to the neocartilage. Unlike 6.7 kPa, both 3.3 and 5.0 kPa significantly increased neocartilage compressive properties by 42% and 48% over untreated controls, respectively. Experiment 3 examined how the passive axial compression regimen developed from the previous phases interacted with a bioactive regimen (transforming growth factor [TGF]-β1, chondroitinase ABC, and lysyl oxidase-like 2). Passive axial compression significantly improved the relaxation modulus compared with bioactive treatment alone. Furthermore, a combined treatment of compressive and bioactive stimulation improved the tensile properties of neocartilage 2.6-fold compared with untreated control. The ability to create robust articular cartilage from passaged costal
Sociocognitive Factors and Perceived Consequences Associated with Alternative Forms of Alcohol Use
Braitman, Abby L.; Linden-Carmichael, Ashley N.; Stamates, Amy L.; Lau-Barraco, Cathy
2017-01-01
Objective: Popular media have highly publicized alternative forms of alcohol use (e.g., eyeballing, inhaling alcohol vapor) among college students as a growing concern, possibly associated with severe health risks. Formative research indicates rarity of use. Participants and Methods: College students (Study 1: n = 411; Study 2: n = 687) completed…
Zhan, Jiao; Lin, Haotian; Zhang, Xinyu; Chen, Weirong; Liu, Yizhi
2013-06-01
Congenital cataract is the main cause of blindness in children, with significantly varying treatment effects. The development of axial length is an important factor that affects the prognosis of these children. However, when compared with the eyes of normal children, the mechanism of growth of the axial length is so complicated that the reported findings differ significantly in terms of the measuring apparatus, assessment methods, and statistical outcome, making the rule of axial length development still unclear. In this paper, we first review the process of axial length development in normal healthy children and compare different hypotheses about certain factors that could affect the development of axial length. The results of some current research about the characteristics of axial length development in congenital cataract children are then reviewed. Lastly, the advantages and disadvantages of current axial length measurements methods are compared and analyzed. The purpose of this review is to improve our understanding of the complexity and importance of axial length development and to suggest better use of axial length monitoring measurements in congenital cataract children for pediatric ophthalmologists, with the hope of offering assistance that will enhance long-term therapeutic effects for these children.
Equivalence between Zwanziger's horizon function and Gribov's no-pole ghost form factor
Energy Technology Data Exchange (ETDEWEB)
Gomez, A.J., E-mail: ajgomez@uerj.b [UERJ - Universidade do Estado do Rio de Janeiro, Instituto de Fisica - Departamento de Fisica Teorica, Rua Sao Francisco Xavier 524, 20550-013 Maracana, Rio de Janeiro (Brazil); Guimaraes, M.S., E-mail: marceloguima@gmail.co [UERJ - Universidade do Estado do Rio de Janeiro, Instituto de Fisica - Departamento de Fisica Teorica, Rua Sao Francisco Xavier 524, 20550-013 Maracana, Rio de Janeiro (Brazil); Sobreiro, R.F., E-mail: sobreiro@if.uff.b [UFF - Universidade Federal Fluminense, Instituto de Fisica, Campus da Praia Vermelha, Avenida General Milton Tavares de Souza s/n, 24210-346, Niteroi (Brazil); Sorella, S.P., E-mail: sorella@uerj.b [UERJ - Universidade do Estado do Rio de Janeiro, Instituto de Fisica - Departamento de Fisica Teorica, Rua Sao Francisco Xavier 524, 20550-013 Maracana, Rio de Janeiro (Brazil)
2010-01-18
The ghost form factor entering the Gribov no-pole condition is evaluated till the third order in the gauge fields. The resulting expression turns out to coincide with Zwanziger's horizon function implementing the restriction to the Gribov region in the functional integral.
Four-loop photon quark form factor and cusp anomalous dimension in the large-Nc limit of QCD
International Nuclear Information System (INIS)
Henn, Johannes; Lee, Roman N.; Smirnov, Alexander V.; Smirnov, Vladimir A.; Steinhauser, Matthias
2017-01-01
We compute the four-loop QCD corrections to the massless quark-anti-quark-photon form factor F q in the large-N c limit. From the pole part we extract analytic expressions for the corresponding cusp and collinear anomalous dimensions.
Ezhova, O V; Egorova, E A; Malakhov, V V
2016-05-01
The ultrastructure of the axial organ of Asterias amurensis has been studied The organ is a network of canals of the axial coelom separated by haemocoelic spaces. The axial coelom is lined with two types of monociliary cells: podocytes and musculo-epithelial cells. Podocytes form numerous basal processes adjacent to the basal lamina on the coelomic side. Musculo-epithelial cells form processes running along the basal lamina. Some bundles of these processes wrapped in the basal lamina pass through haemocoelic spaces between neighboring coelomic canals. It is hypothesized that the axial organ serves for filtration of fluid from haemocoelic spaces into the axial coelom cavity, from which urine is excreted through the madreporite to the exterior.
Cdx and Hox Genes Differentially Regulate Posterior Axial Growth in Mammalian Embryos
Young, Teddy; Rowland, Jennifer Elizabeth; van de Ven, Cesca; Bialecka, Monika; Novoa, Ana; Carapuco, Marta; van Nes, Johan; de Graaff, Wim; Duluc, Isabelle; Freund, Jean-Noel; Beck, Felix; Mallo, Moises; Deschamps, Jacqueline
2009-01-01
Hox and Cdx transcription factors regulate embryonic positional identities. Cdx mutant mice display posterior body truncations of the axial skeleton, neuraxis, and caudal urorectal structures. We show that trunk Hox genes stimulate axial extension, as they can largely rescue these Cdx mutant
The Ellipsoid Factor for quantification of rods, plates and intermediate forms in 3D geometries
Directory of Open Access Journals (Sweden)
Michael eDoube
2015-02-01
Full Text Available The Ellipsoid Factor (EF is a method for the local determination of the rod- or plate-like nature of porous or spongy continua. EF at a point within a 3D structure is defined as the difference in axis ratios of the greatest ellipsoid which fits inside the structure and which contains the point of interest, and ranges from -1 for strongly oblate (discus-shaped ellipsoids, to +1 for strongly prolate (javelin-shaped ellipsoids. For an ellipsoid with axes a ≤ b ≤ c, EF = a/b – b/c. Here, EF is demonstrated in a Java plugin, Ellipsoid Factor for ImageJ, distributed in the BoneJ plugin collection. Ellipsoid Factor utilises an ellipsoid optimisation algorithm which assumes that maximal ellipsoids are centred on the medial axis, then dilates, rotates and translates slightly each ellipsoid until it cannot increase in volume any further. Ellipsoid Factor successfully identifies rods, plates and intermediate structures within trabecular bone, and summarises the distribution of geometries with an overall EF mean and standard deviation, EF histogram and Flinn diagram displaying a/b versus b/c. Ellipsoid Factor is released to the community for testing, use, and improvement.
Axial diagnostic package for Z
International Nuclear Information System (INIS)
Nash, T.J.; Derzon, M.S.; Chandler, G.
1998-06-01
The authors have developed and fielded an axial diagnostic package for the 20 MA, 100 ns, z-pinch driver Z. The package is used to diagnose dynamic hohlraum experiments which require an axial line of sight. The heart of the package is a reentrant cone originally used to diagnose ion-beam-driven hohlraums on PBFA-H. It has one diagnostic line of sight at 0 degrees, 4 at 6 degrees, and 4 at 9 degrees. In addition it has a number of viewing, alignment, and vacuum feedthrough ports. The front of the package sits approximately 5 feet from the pinch. This allows much closer proximity to the pinch, with inherently better resolution and signal, than is presently possible in viewing the pinch from the side. Debris that is preferentially directed along the axis is mitigated by two apertures for each line of sight, and by fast valves and imaging pinholes or cross slits for each diagnostic. In the initial run with this package they fielded a time resolved pinhole camera, a five-channel pinhole-apertured x-ray diode array, a bolometer, a spatially resolved time-integrated crystal spectrometer, and a spatially and temporally resolved crystal spectrometer. They present data obtained from these diagnostics in the dynamic hohlraum research conducted on Z
International Nuclear Information System (INIS)
Grande, T.; Gonzalez, J.; Tejero, C.; Maganto, G.; Bueren, J.A.
1990-01-01
The production of humoral factors that stimulate spleen colony-forming units (CFU-S) has been studied in irradiated mice using an in vivo diffusion chamber assay. The experiments show that a significant release of factors that stimulate CFU-S takes place in the first few days after irradiation with moderate doses of 1.5 or 5 Gy. In contrast, the release of significant amounts of these humoral factors was not seen in animals irradiated with either low (0.75 Gy) or high (10 Gy) doses of X rays. The correlation observed between the production of factors that stimulate the CFU-S and the hemopoietic regeneration kinetics of the irradiated mice suggests that these factors represent part of the physiological regulators controlling the proliferation of CFU-S
Sanchez, Robert O.; Gunewardena, Shelton; Masi, James V.
2005-03-29
An electrical component in the form of an inductor or transformer is disclosed which includes one or more coils and a magnetic polymer material located near the coils or supporting the coils to provide an electromagnetic interaction therewith. The magnetic polymer material is preferably a cured magnetic epoxy which includes a mercaptan derivative having a ferromagnetic atom chemically bonded therein. The ferromagnetic atom can be either a transition metal or rare-earth atom.
Iversen, Sigrun
2010-01-01
This thesis investigates the aggressive behaviour in 102 city dogs of different breeds in Berlin. The results presented in this thesis are based on an aggression test especially developed for this investigation and consisting of 31 test sequences, as well as a physical examination. The purpose of the test was to explore the different forms of aggressive behaviour shown by dogs toward humans and to ascertain possibly existing stimulus thresholds for aggressive behaviour. Before the test ...
Elevated temperature axial and torsional fatigue behavior of Haynes 188
Bonacuse, Peter J.; Kalluri, Sreeramesh
1995-01-01
The results are reported for high-temperature axial and torsional low-cycle fatigue experiments performed at 760 C in air on thin-walled tubular specimens of Haynes 188, a wrought cobalt-based superalloy. Data are also presented for mean coefficient of thermal expansion, elastic modulus, and shear modulus at various temperatures from room to 1000 C, and monotonic and cyclic stress-strain curves in tension and in shear at 760 C. This data set is used to evaluate several multiaxial fatigue life models (most were originally developed for room temperature multiaxial life prediction) including von Mises equivalent strain range (ASME Boiler and Pressure Code), Manson-Halford, modified multiaxiality factor (proposed in this paper), modified Smith-Watson-Topper, and Fatemi-Socie-Kurath. At von Mises equivalent strain ranges (the torsional strain range divided by the square root of 3, taking the Poisson's ratio to be 0.5), torsionally strained specimens lasted, on average, factors of 2 to 3 times longer than axially strained specimens. The modified multiaxiality factor approach shows promise as a useful method of estimating torsional fatigue life from axial fatigue data at high temperatures. Several difficulties arose with the specimen geometry and extensometry used in these experiments. Cracking at extensometer probe indentations was a problem at smaller strain ranges. Also, as the largest axial and torsional strain range fatigue tests neared completion, a small amount of specimen buckling was observed.
Axial weak currents in the Wess-Zumino term
International Nuclear Information System (INIS)
Fujikawa, Kazuo
1986-01-01
In a simplified model lagrangian of 3 quarks with an SU(2)sub(L) gauging of chiral SU(3)sub(L)xSU(3)sub(R) to introduce W-boson, we analyse certain complications associated with the low-energy theorem including axial weak fields. We first show that the low-energy amplitude is independent of the form of the quark-level anomalous identity, whether in the covariant form or the consistent form. However, the interplay of the short-distance dynamics (anomalous identity) and the long-distance dynamics (low-energy theorem) becomes involved in the presence of axial fields. We then discuss what kinds of conditions single out the gauged Wess-Zumino term as a low-energy effective action. The connection of the low-energy theorem with the 't Hooft anomaly matching condition is also discussed. (orig.)
The reliability and factor structure of Thai Young Schema Questionnaire-Short Form 3.
Sakulsriprasert, Chaiyun; Phukao, Darunee; Kanjanawong, Suree; Meemon, Natthani
2016-12-01
Previous research which documented the psychometric properties of Young Schema Questionnaire (YSQ) was conducted in Western countries. The current research examined the reliability and factor structure of the Thai version of the Young Schema-Short From-3 (YSQ-S3). The participants were 622 undergraduates (62% females) recruited from three universities in Chiang Mai, Thailand. Results suggested acceptable internal consistency of 18 early maladaptive schemas (EMSs) (Cronbach's α range from 0.619 to 0.846). Confirmatory factor analysis confirmed the factor structures of 18 EMSs. The results failed to support Young's theoretical schema domain. The authors indicated a four-factor solution as the best alternative second-order model for this population. In conclusion, the Thai version of YSQ-S3 is psychometrically sound questionnaire that can be utilized for assessing EMS, both for research and practice purposes. The current study further provides evidence supporting the existence of 18 EMSs in the non-Western context. Copyright © 2016. Published by Elsevier B.V.
Models of Anaylzing the Influence of Factors on Forming Profit Rate
Directory of Open Access Journals (Sweden)
Klara S. Jakovčević
2014-04-01
Full Text Available The analysis in this paper is focused on identifying the impact of individual factors on the elements of the profit rate. The primary aim of this work is a methodological overview of solutions for understanding the full content of the profit rate as a cause of economic quality as well as indicators of the results of reproduction. Application of model analysis of profit rate factors was performed in an enterprise from Serbia that manufactures construction materials from baked clay. The aim is of application is to test the range in determining elements and factors of economic success of the enterprise, and quantification of changes in its assumptions. The results are useful guideline for the management to take organizational measures to increase the economic success of the enterprise. This means eliminating the negative, emphasizing the positive impact of objectively, and organizational factors to make higher economic success. Based on empirical research, it could be concluded that the proposed quantitative models of analyzing the dynamics of enterprise business quality could be applied in practice.
Baculovirus Per Os Infectivity Factors Form a Complex on the Surface of Occlusion-Derived Virus
Peng, K.; Oers, van M.M.; Hu, Z.; Lent, van J.W.M.; Vlak, J.M.
2010-01-01
Five highly conserved per os infectivity factors, PIF1, PIF2, PIF3, PIF4, and P74, have been reported to be essential for oral infectivity of baculovirus occlusion-derived virus (ODV) in insect larvae. Three of these proteins, P74, PIF1, and PIF2, were thought to function in virus binding to insect
Forming Factors of Russia International Image in the Conflict between Georgia and South Ossetia
Directory of Open Access Journals (Sweden)
I Y Glinskaya
2009-12-01
Full Text Available The author analyses the factors of determining the international political image of Russia in the context of Russian policy in the Northern Caucasus. Relations between Russia and Georgia, as well as changes of international image of Russia are evaluated.
Factors Forming Collaboration within the Knowledge Triangle of Education, Research and Innovation
Zascerinska, Jelena; Ahrens, Andreas; Bassus, Olaf
2009-01-01
A proper combination of education, research and innovation is provided by varied cooperative networks. However, the success of collaboration within a multicultural environment requires that the key factors enabling synergy between education, research and innovation have to be considered. Aim of the following paper is to identify and to analyze…
Characterization of water-forming NADH oxidases for co-factor regeneration
DEFF Research Database (Denmark)
Rehn, Gustav; Pedersen, Asbjørn Toftgaard; J. Charnock, Simon
an environmentaland economic perspective [1]. Alcohol dehydrogenases (ADH) offer one such alternative. However, the reaction requires the oxidized nicotinamide co-factor (NAD+) that must be recycled due to its high cost contribution. One regeneration method that offers certain advantages is the oxidation of NADH...
Cortés-Flores, Jorge; Hernández-Esquivel, Karen Beatriz; González-Rodríguez, Antonio; Ibarra-Manríquez, Guillermo
2017-01-01
Analyses of the influence of temporal variation in abiotic factors on flowering phenology of tropical dry forest species have not considered the possible response of species with different growth forms and pollination syndromes, while controlling for phylogenetic relationships among species. Here, we investigated the relationship between flowering phenology, abiotic factors, and plant functional attributes, while controlling for phylogenetic relationship among species, in a dry forest community in Mexico. We characterized flowering phenology (time and duration) and pollination syndromes of 55 tree species, 49 herbs, 24 shrubs, 15 lianas, and 11 vines. We tested the influence of pollination syndrome, growth form, and abiotic factors on flowering phenology using phylogenetic generalized least squares. We found a relationship between flowering duration and time. Growth form was related to flowering time, and the pollination syndrome had a more significant relationship with flowering duration. Flowering time variation in the community was explained mainly by abiotic variables, without an important phylogenetic effect. Flowering time in lianas and trees was negatively and positively correlated with daylength, respectively. Functional attributes, environmental cues, and phylogeny interact with each other to shape the diversity of flowering patterns. Phenological differentiation among species groups revealed multiples strategies associated with growth form and pollination syndromes that can be important for understanding species coexistence in this highly diverse plant community. © 2017 Botanical Society of America.
International Nuclear Information System (INIS)
Krapchev, V.
1976-01-01
In the framework of the two-dimensional scalar quantum theory of the bag model of Chodos et al a definition of the physical field and a general scheme for constructing a physical state are given. Some of the difficulties associated with such an approach are exposed. Expressions for the physical current and the elastic form factor are given. The calculation of the latter is restricted at first to the approximation in which the mapping from a bag of changing shape to a fixed domain is realized only by a term which is a diagonal, bilinear function of the creation and annihilation operators. This is done for the case of a one-mode and an infinite-mode bag theory. By computing the form factor in an exact one-mode bag model it is shown that the logarithmic falloff of the asymptotic term is the same as the one in the approximation. On the basis of this a form for the asymptotic behavior of the form factor is suggested which may be correct for the general two-dimensional scalar bag theory
Λc→N form factors from lattice QCD and phenomenology of Λc→n ℓ+νℓ and Λc→p μ+μ- decays
Meinel, Stefan
2018-02-01
A lattice QCD determination of the Λc→N vector, axial vector, and tensor form factors is reported. The calculation was performed with 2 +1 flavors of domain-wall fermions at lattice spacings of a ≈0.11 and 0.085 fm and pion masses in the range 230 MeV ≲mπ≲350 MeV . The form factors are extrapolated to the continuum limit and the physical pion mass using modified z expansions. The rates of the charged-current decays Λc→n e+νe and Λc→n μ+νμ are predicted to be (0.405 ±0.01 6stat±0.02 0syst) |Vc d|2 ps-1 and (0.396 ±0.01 6stat±0.02 0syst) |Vc d|2 ps-1 , respectively. The phenomenology of the rare charm decay Λc→p μ+μ- is also studied. The differential branching fraction, the fraction of longitudinally polarized dimuons, and the forward-backward asymmetry are calculated in the standard model and in an illustrative new-physics scenario.
The herpes viral transcription factor ICP4 forms a novel DNA recognition complex
Tunnicliffe, Richard B.; Lockhart-Cairns, Michael P.; Levy, Colin; Mould, A. Paul; Jowitt, Thomas A.; Sito, Hilary; Baldock, Clair; Sandri-Goldin, Rozanne M.
2017-01-01
Abstract The transcription factor ICP4 from herpes simplex virus has a central role in regulating the gene expression cascade which controls viral infection. Here we present the crystal structure of the functionally essential ICP4 DNA binding domain in complex with a segment from its own promoter, revealing a novel homo-dimeric fold. We also studied the complex in solution by small angle X-Ray scattering, nuclear magnetic resonance and surface-plasmon resonance which indicated that, in addition to the globular domain, a flanking intrinsically disordered region also recognizes DNA. Together the data provides a rationale for the bi-partite nature of the ICP4 DNA recognition consensus sequence as the globular and disordered regions bind synergistically to adjacent DNA motifs. Therefore in common with its eukaryotic host, the viral transcription factor ICP4 utilizes disordered regions to enhance the affinity and tune the specificity of DNA interactions in tandem with a globular domain. PMID:28505309
Kwon, Youngho; Cha, Jaeyul; Chiang, Jennifer; Tran, Grant; Nislow, Corey; Hur, Jae-Seoun; Kwak, Youn-Sig
2016-06-01
Lichen-forming fungi and extracts derived from them have been used as alternative medicine sources for millennia and recently there has been a renewed interest in their known bioactive properties for anticancer agents, cosmetics and antibiotics. Although lichen-forming fungus-derived compounds are biologically and commercially valuable, few studies have been performed to determine their modes of action. This study used chemical-genetic and chemogenomic high-throughput analyses to gain insight into the modes of action of Caloplaca flavoruscens extracts. High-throughput screening of 575 lichen extracts was performed and 39 extracts were identified which inhibited yeast growth. A C. flavoruscens extract was selected as a promising antifungal and was subjected to genome-wide haploinsufficiency profiling and homozygous profiling assays. These screens revealed that yeast deletion strains lacking Rsc8, Pro1 and Toa2 were sensitive to three concentrations (IC25.5, IC25 and IC50, respectively) of C. flavoruscens extract. Gene-enrichment analysis of the data showed that C. flavoruscens extracts appear to perturb transcription and chromatin remodeling. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Electric machines with axial magnetic flux
Nuca, I.; Ambros, T.; Burduniuc, M.; Deaconu, S. I.; Turcanu, A.
2018-01-01
The paper contains information on the performance of axial machines compared to cylindrical ones. At the same time, various constructive schemes of synchronous electromechanical converters with permanent magnets and asynchronous with short-circuited rotor are presented. In the developed constructions, the aim is to maximize the usage of the material of the stator windings. The design elements of the axial machine magnetic system are presented. The FEMM application depicted the array of the magnetic field of an axial machine.
Axial vector mass spectrum and mixing angles
International Nuclear Information System (INIS)
Caffarelli, R.V.; Kang, K.
1976-01-01
Spectral sum rules of the axial-vector current and axial-vector current-pseudoscalar field are used to study the axial-vector mass spectrum and mixing angles, as well as the decay constants and mixing angles of the pseudoscalar mesons. In general, the result is quite persuasive for the existence of the Jsup(PC) = 1 ++ multiplet in which one has a canonical D-E mixing. (Auth.)
Directory of Open Access Journals (Sweden)
Priyanka Gupta
2017-11-01
Full Text Available The GATA gene family is one of the most conserved families of transcription factors, playing a significant role in different aspects of cellular processes, in organisms ranging from fungi to angiosperms. GATA transcription factors are DNA-binding proteins, having a class IV zinc-finger motif CX2CX17−20CX2C followed by a highly basic region and are known to bind a consensus sequence WGATAR. In plants, GATAs are known to be involved in light-dependent gene regulation and nitrate assimilation. However, a comprehensive analysis of these GATA gene members has not yet been highlighted in rice when subjected to environmental stresses. In this study, we present an overview of the GATA gene family in rice (OsGATA in terms of, their chromosomal distribution, domain architecture, and phylogeny. Our study has revealed the presence of 28 genes, encoding 35 putative GATA transcription factors belonging to seven subfamilies in the rice genome. Transcript abundance analysis in contrasting genotypes of rice—IR64 (salt sensitive and Pokkali (salt tolerant, for individual GATA members indicated their differential expression in response to various abiotic stresses such as salinity, drought, and exogenous ABA. One of the members of subfamily VII—OsGATA23a, emerged as a multi-stress responsive transcription factor giving elevated expression levels in response to salinity and drought. ABA also induces expression of OsGATA23a by 35 and 55-folds in IR64 and Pokkali respectively. However, OsGATA23b, an alternative splice variant of OsGATA23 did not respond to above-mentioned stresses. Developmental regulation of the OsGATA genes based on a publicly available microarray database showed distinct expression patterns for most of the GATA members throughout different stages of rice development. Altogether, our results suggest inherent roles of diverse OsGATA factors in abiotic stress signaling and also throw some light on the tight regulation of the spliced variants of
Centrifugal and axial compressor control
McMillan, Gregory K
2009-01-01
Control engineers, mechanical engineers and mechanical technicians will learn how to select the proper control systems for axial and centrifugal compressors for proper throughput and surge control, with a particular emphasis on surge control. Readers will learn to understand the importance of transmitter speed, digital controller sample time, and control valve stroking time in helping to prevent surge. Engineers and technicians will find this book to be a highly valuable guide on compressor control schemes and the importance of mitigating costly and sometimes catastrophic surge problems. It can be used as a self-tutorial guide or in the classroom with the book's helpful end-of-chapter questions and exercises and sections for keeping notes.
Axial channeling of uttrarelativistic electrons
Energy Technology Data Exchange (ETDEWEB)
Telegin, V.I.; Khokonov, M.Kh. (Moskovskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Yadernoj Fiziki)
1982-07-01
The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements.
Axial channeling of uttrarelativistic electrons
International Nuclear Information System (INIS)
Telegin, V.I.; Khokonov, M.Kh.
1982-01-01
The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements
FACTOR STRUCTURE AND PSYCHOMETRIC PROPERTIES OF THE INDEX OF TEACHING STRESS-SHORT FORM (ITS-SF).
Zurlo, Maria Clelia; Pes, Daniela; Romano, Rosaria
2015-12-01
This study analyses factor structure and psychometric properties of the Italian short version of the Index of Teaching Stress-Short Form (ITS-SF). The original version of the ITS (90 items) was submitted to 567 teachers randomly drawn from a cross-section of school levels. Confirmatory factor analysis to check the factor structure was unsatisfactory, and Cronbach's α (.98) indicated a redundancy of items. Exploratory factor analysis was conducted for each section of the test and cross-loading items were eliminated. The resulting ITS-SF consists of 43 items, tapping eight meaningful and adequately reliable dimensions substantially corresponding to all dimensions measured by the original version of the ITS. The Italian short version of the Index of Teaching Stress constitutes a reliable measure of teacher stress in educative interactions.
Axial and Radial Oxylipin Transport.
Gasperini, Debora; Chauvin, Adeline; Acosta, Ivan F; Kurenda, Andrzej; Stolz, Stéphanie; Chételat, Aurore; Wolfender, Jean-Luc; Farmer, Edward E
2015-11-01
Jasmonates are oxygenated lipids (oxylipins) that control defense gene expression in response to cell damage in plants. How mobile are these potent mediators within tissues? Exploiting a series of 13-lipoxygenase (13-lox) mutants in Arabidopsis (Arabidopsis thaliana) that displays impaired jasmonic acid (JA) synthesis in specific cell types and using JA-inducible reporters, we mapped the extent of the transport of endogenous jasmonates across the plant vegetative growth phase. In seedlings, we found that jasmonate (or JA precursors) could translocate axially from wounded shoots to unwounded roots in a LOX2-dependent manner. Grafting experiments with the wild type and JA-deficient mutants confirmed shoot-to-root oxylipin transport. Next, we used rosettes to investigate radial cell-to-cell transport of jasmonates. After finding that the LOX6 protein localized to xylem contact cells was not wound inducible, we used the lox234 triple mutant to genetically isolate LOX6 as the only JA precursor-producing LOX in the plant. When a leaf of this mutant was wounded, the JA reporter gene was expressed in distal leaves. Leaf sectioning showed that JA reporter expression extended from contact cells throughout the vascular bundle and into extravascular cells, revealing a radial movement of jasmonates. Our results add a crucial element to a growing picture of how the distal wound response is regulated in rosettes, showing that both axial (shoot-to-root) and radial (cell-to-cell) transport of oxylipins plays a major role in the wound response. The strategies developed herein provide unique tools with which to identify intercellular jasmonate transport routes. © 2015 American Society of Plant Biologists. All Rights Reserved.
[Characteristics of physical growth of schoolchildren in Mongolia and their forming factors].
Pogorelova, I G; Amgalan, G
The article considers the findings of hygienic assessments of educational conditions in urban and rural schools in Mongolia and socio-economic conditions of living of schoolchildren and analysis of anthropometric measurements of schoolchildren aged of 7-16 years in relation to the assessment of harmonicity of their physical development. Hygienic conditions in Mongolian schools are characterized by improper organization of the educational - accomplishment process, high occupancy rate in classes causing insufficient space for a pupil and disconformity of school furniture parameters of school desks and chairs to growth and age requirements of pupils. Comparative assessment of socio-economic factors revealed (выделено автором) that the majority (84.1%) of rural pupils reside in uncomfortable houses and gerdwellings, 58.5 % - in large families with many children, 46.3 % - in families with poor living conditions. There were obtained data about differences in physical development of urban and rural schoolchildren pronounced with age by the gain in the number of children with disharmonious development and children with lower physical indices of the development, delayed by 1-2 years appearance of the crossing of growth and growth shift typical for rural children in comparison with their urban counterparts. According to results of multivariate regression analysis most significant factors for the formation of physical development of school children in descending order are academic workload, the place of residence, the number of children in the family, uncomfortable living conditions, household income and parent’s education. In the presence of these factors, the risk of the formation of disharmonious physical growth of school children increases by 1.8-2.8 times. The probability of the risk offormation of disharmonious physical development of schoolchildren living in rural areas was found to be by 2.5 times more than for their urban counterparts. The results
Scott, Kerry; George, Asha S; Harvey, Steven A; Mondal, Shinjini; Patel, Gupteswar; Ved, Rajani; Garimella, Surekha; Sheikh, Kabir
2017-01-01
Health committees are a common strategy to foster community participation in health. Efforts to strengthen committees often focus on technical inputs to improve committee form (e.g. representative membership) and functioning (e.g. meeting procedures). However, porous and interconnected contextual spheres also mediate committee effectiveness. Using a framework for contextual analysis, we explored the contextual features that facilitated or hindered Village Health, Sanitation and Nutrition Committee (VHSNC) functionality in rural north India. We conducted interviews (n = 74), focus groups (n = 18) and observation over 1.5 years. Thematic content analysis enabled the identification and grouping of themes, and detailed exploration of sub-themes. While the intervention succeeded in strengthening committee form and functioning, participant accounts illuminated the different ways in which contextual influences impinged on VHSNC efficacy. Women and marginalized groups navigated social hierarchies that curtailed their ability to assert themselves in the presence of men and powerful local families. These dynamics were not static and unchanging, illustrated by pre-existing cross-caste problem solving, and the committee's creation of opportunities for the careful violation of social norms. Resource and capacity deficits in government services limited opportunities to build relationships between health system actors and committee members and engendered mistrust of government institutions. Fragmented administrative accountability left committee members bearing responsibility for improving local health without access to stakeholders who could support or respond to their efforts. The committee's narrow authority was at odds with widespread community needs, and committee members struggled to involve diverse government services across the health, sanitation, and nutrition sectors. Multiple parallel systems (political decentralization, media and other village groups) presented
Directory of Open Access Journals (Sweden)
Kerry Scott
Full Text Available Health committees are a common strategy to foster community participation in health. Efforts to strengthen committees often focus on technical inputs to improve committee form (e.g. representative membership and functioning (e.g. meeting procedures. However, porous and interconnected contextual spheres also mediate committee effectiveness. Using a framework for contextual analysis, we explored the contextual features that facilitated or hindered Village Health, Sanitation and Nutrition Committee (VHSNC functionality in rural north India. We conducted interviews (n = 74, focus groups (n = 18 and observation over 1.5 years. Thematic content analysis enabled the identification and grouping of themes, and detailed exploration of sub-themes. While the intervention succeeded in strengthening committee form and functioning, participant accounts illuminated the different ways in which contextual influences impinged on VHSNC efficacy. Women and marginalized groups navigated social hierarchies that curtailed their ability to assert themselves in the presence of men and powerful local families. These dynamics were not static and unchanging, illustrated by pre-existing cross-caste problem solving, and the committee's creation of opportunities for the careful violation of social norms. Resource and capacity deficits in government services limited opportunities to build relationships between health system actors and committee members and engendered mistrust of government institutions. Fragmented administrative accountability left committee members bearing responsibility for improving local health without access to stakeholders who could support or respond to their efforts. The committee's narrow authority was at odds with widespread community needs, and committee members struggled to involve diverse government services across the health, sanitation, and nutrition sectors. Multiple parallel systems (political decentralization, media and other village groups
International Nuclear Information System (INIS)
Hazarika, Bhaskar Jyoti; Choudhury, D.K.
2015-01-01
We use variationally improved perturbation theory (VIPT) for calculating the elastic form factors and charge radii of D, D s , B, B s and B c mesons in a quantum chromodynamics (QCD)-inspired potential model. For that, we use linear-cum-Coulombic potential and opt the Coulombic part first as parent and then the linear part as parent. The results show that charge radii and form factors are quite small for the Coulombic parent compared to the linear parent. Also, the analysis leads to a lower as well as upper bounds on the four-momentum transfer Q 2 , hinting at a workable range of Q 2 within this approach, which may be useful in future experimental analyses. Comparison of both the options shows that the linear parent is the better option. (author)
Yang, Gang
2016-12-30
Using color-kinematics duality, we construct for the first time the full integrand of the five-loop Sudakov form factor in N=4 super-Yang-Mills theory, including nonplanar contributions. This result also provides a first manifestation of the color-kinematics duality at five loops. The integrand is explicitly ultraviolet finite when D<26/5, coincident with the known finiteness bound for amplitudes. If the double-copy method could be applied to the form factor, this would indicate an interesting ultraviolet finiteness bound for N=8 supergravity at five loops. The result is also expected to provide an essential input for computing the five-loop nonplanar cusp anomalous dimension.
Golubeva, E Yu
2016-01-01
The satisfaction of the quality of life (QOL) in elderly age is discussed. There have been considered the satisfaction of QOL depending on the form of social service in urban and rural areas. The key factors influencing the QOL in various forms of services is defined. They include: rural life satisfaction is largely dependent on the availability of family than on the health and financial status; in a special house for single elderly life satisfaction is determined only by the state of health due to the large number of chronic diseases, in stationary social services very important factor is loneliness, isolation that creates some feeling of being tired of life, depression, provocation the abuse of alcohol.
A Measurement of the Branching Ratio and Form-Factor of $K_L \\to \\mu^+ \\mu^- \\gamma$
Energy Technology Data Exchange (ETDEWEB)
Quinn, Gene Breese [Chicago U., EFI
2000-01-01
We report on the analysis of the rare decay $K_L \\to \\mu^+\\mu^- \\gamma$ using the 1997 data from the KTeV experiment at Fermilab. A total of 9327 candidate events are observed with 2.4% background. We find that BR($K_L \\to \\mu^+\\mu^- \\gamma$) = (3.70 $\\pm$ 0.04 stat $\\pm$ 0.07syst) $\\pm$ $10^{-7}$. The BMS form factor parameter $\\alpha_{K*}$ is measured to be $\\alpha_{K*}$ = -0.163 $^{+0.026}_{-0.027}$. In addition, we make the first experimental measurement of the parameter $\\alpha$ from the D'Ambrosio, Isidori, and Portoles form factor, finding $\\alpha$ = -1.55 $\\pm$ 0.09. This measurement of $\\alpha$ limits the CKM parameter $\\rho$ > -0.2.
Silva, António; Urbano, Diana; Kim, Hyun-Chul
2018-02-01
We investigate the flavor decomposition of the electromagnetic form factors of the nucleon, based on the chiral quark-soliton model (χQSM) with symmetry-conserving quantization. We consider the rotational 1/N_c and linear strange-quark mass (ms) corrections. We discuss the results of the flavor-decomposed electromagnetic form factors in comparison with the recent experimental data. In order to see the effects of the strange quark, we compare the SU(3) results with those of SU(2). Finally, we discuss the transverse charge densities for both unpolarized and polarized nucleons. The transverse charge density inside a neutron turns out to be negative in the vicinity of the center within the SU(3) χQSM, which can be explained by the contribution of the strange quark.
The electric dipole form factor of the nucleon in chiral perturbation theory to sub-leading order
Energy Technology Data Exchange (ETDEWEB)
Mereghetti, E., E-mail: emanuele@physics.arizona.ed [Department of Physics, University of Arizona, Tucson, AZ 85721 (United States); Vries, J. de [KVI, Theory Group, University of Groningen 9747 AA Groningen (Netherlands); Hockings, W.H. [Department of Mathematics and Natural Sciences, Blue Mountain College, Blue Mountain, MS 38610 (United States); Maekawa, C.M. [Instituto de Matematica, Estatistica e Fisica, Universidade Federal do Rio Grande, Campus Carreiros, PO Box 474, 96201-900 Rio Grande, RS (Brazil); Kolck, U. van [Department of Physics, University of Arizona, Tucson, AZ 85721 (United States)
2011-01-24
The electric dipole form factor (EDFF) of the nucleon stemming from the QCD {theta}-bar term and from the quark color-electric dipole moments is calculated in chiral perturbation theory to sub-leading order. This is the lowest order in which the isoscalar EDFF receives a calculable, non-analytic contribution from the pion cloud. In the case of the {theta}-bar term, the expected lower bound on the deuteron electric dipole moment is |d{sub d}|{>=}1.4.10{sup -4{theta}}-bar e fm. The momentum dependence of the isovector EDFF is proportional to a non-derivative time-reversal-violating pion-nucleon coupling, and the scale for momentum variation-appearing, in particular, in the radius of the form factor-is the pion mass.
Measurement of B -> D Form Factors in the Semileptonic Decay B -> D* l nu at BaBar
Energy Technology Data Exchange (ETDEWEB)
Gill, Mandeep Singh; /SLAC
2006-01-27
We present here the results of a measurement of the three semileptonic form factors involved in the decay B{sup 0} {yields} D*{ell}{nu}, where {ell} is one of the two light charged leptons (i.e. an electron or muon--though the final results in this work are determined only for {ell} = electron). This measurement uses the Babar 2000-2002 data set, which is altogether approximately 85 x 10{sup 6} B{bar B}-pairs in 78 fb{sup -1} of integrated luminosity. The D*{sup +} was reconstructed in the channel D*{sup +} {yields} D{sup 0}{pi}{sup +}, and the D{sup 0} in the channel D{sup 0} {yields} K{sup -}{pi}{sup +}. This analysis was based ultimately on {approx} 16,386 reconstructed events with an estimated background contamination of {approx} 15%. The method of the measurement was to perform a unbinned maximum likelihood fit in the four kinematic variables that describe the decay for the three form factor parameters R{sub 1}, R{sub 2}, and {rho}{sup 2}. The results obtained for the form factor ratios are R{sub 1} = 1.328 {+-} 0.055 {+-} 0.025 {+-} 0.025 and R{sub 2} = 0.920 {+-} 0.044 {+-} 0.020 {+-} 0.013 for the ratios and {rho}{sup 2} = 0.769 {+-} 0.039 {+-} 0.019 {+-} 0.032 for the form factor slope. The errors given are statistical, Monte Carlo statistical and systematic respectively.
Directory of Open Access Journals (Sweden)
V I Kazarenkov
2013-12-01
Full Text Available In the article the problem of forming an interest in learning in students through the extracurricular activity is considered; the importance of the extracurricular activity as a factor of the development of the interest in educationally-cognitive activity in the college students with poor academic performance is revealed; the conditions providing the efficiency of using the extracurricular activity for the stimulation of the interest in learning in students with poor academic performance are accentuated.
Li, Chih-Ying; Waid-Ebbs, Julia; Velozo, Craig A; Heaton, Shelley C
2016-01-01
Social problem-solving deficits characterise individuals with traumatic brain injury (TBI), and poor social problem solving interferes with daily functioning and productive lifestyles. Therefore, it is of vital importance to use the appropriate instrument to identify deficits in social problem solving for individuals with TBI. This study investigates factor structure and item-level psychometrics of the Social Problem Solving Inventory-Revised: Short Form (SPSI-R:S), for adults with moderate and severe TBI. Secondary analysis of 90 adults with moderate and severe TBI who completed the SPSI-R:S was performed. An exploratory factor analysis (EFA), principal components analysis (PCA) and Rasch analysis examined the factor structure and item-level psychometrics of the SPSI-R:S. The EFA showed three dominant factors, with positively worded items represented as the most definite factor. The other two factors are negative problem-solving orientation and skills; and negative problem-solving emotion. Rasch analyses confirmed the three factors are each unidimensional constructs. It was concluded that the total score interpretability of the SPSI-R:S may be challenging due to the multidimensional structure of the total measure. Instead, we propose using three separate SPSI-R:S subscores to measure social problem solving for the TBI population.
Li, Chih-Ying; Waid-Ebbs, Julia; Velozo, Craig A.; Heaton, Shelley C.
2016-01-01
Primary Objective Social problem solving deficits characterize individuals with traumatic brain injury (TBI). Poor social problem solving interferes with daily functioning and productive lifestyles. Therefore, it is of vital importance to use the appropriate instrument to identify deficits in social problem solving for individuals with TBI. This study investigates factor structure and item-level psychometrics of the Social Problem Solving Inventory-Revised Short Form (SPSI-R:S), for adults with moderate and severe TBI. Research Design Secondary analysis of 90 adults with moderate and severe TBI who completed the SPSI-R:S. Methods and Procedures An exploratory factor analysis (EFA), principal components analysis (PCA) and Rasch analysis examined the factor structure and item-level psychometrics of the SPSI-R:S. Main Outcomes and Results The EFA showed three dominant factors, with positively worded items represented as the most definite factor. The other two factors are negative problem solving orientation and skills; and negative problem solving emotion. Rasch analyses confirmed the three factors are each unidimensional constructs. Conclusions The total score interpretability of the SPSI-R:S may be challenging due to the multidimensional structure of the total measure. Instead, we propose using three separate SPSI-R:S subscores to measure social problem solving for the TBI population. PMID:26052731
Mobile health IT: The effect of user interface and form factor on doctor-patient communication
DEFF Research Database (Denmark)
Alsos, Ole Andreas; Das, Anita; Svanæs, Dag
2012-01-01
-establishment of eye contact, better verbal and non-verbal contact, more gesturing, good visibility of actions, and quick information retrieval. The digital information devices lacked many of these affordances; physicians’ actions were not visible for the patients, the user interfaces required much attention...... support or hinder aspects of doctor–patient communication, such as face-to-face dialogue, nonverbal communication, and action transparency. Method The study draws on two different experimental simulation studies where 22 doctors, in 80 simulated ward rounds, accessed patient-related information from...... that physicians can use the devices to support face-to-face dialogue, nonverbal communication, and action visibility. The ability to facilitate and support the doctor–patient collaboration is a noteworthy usability factor in the design of mobile EPR systems. The paper also presents possible design guidelines...
Posterior composite restoration update: focus on factors influencing form and function
Bohaty, Brenda S; Ye, Qiang; Misra, Anil; Sene, Fabio; Spencer, Paulette
2013-01-01
Restoring posterior teeth with resin-based composite materials continues to gain popularity among clinicians, and the demand for such aesthetic restorations is increasing. Indeed, the most common aesthetic alternative to dental amalgam is resin composite. Moderate to large posterior composite restorations, however, have higher failure rates, more recurrent caries, and increased frequency of replacement. Investigators across the globe are researching new materials and techniques that will improve the clinical performance, handling characteristics, and mechanical and physical properties of composite resin restorative materials. Despite such attention, large to moderate posterior composite restorations continue to have a clinical lifetime that is approximately one-half that of the dental amalgam. While there are numerous recommendations regarding preparation design, restoration placement, and polymerization technique, current research indicates that restoration longevity depends on several variables that may be difficult for the dentist to control. These variables include the patient’s caries risk, tooth position, patient habits, number of restored surfaces, the quality of the tooth–restoration bond, and the ability of the restorative material to produce a sealed tooth–restoration interface. Although clinicians tend to focus on tooth form when evaluating the success and failure of posterior composite restorations, the emphasis must remain on advancing our understanding of the clinical variables that impact the formation of a durable seal at the restoration–tooth interface. This paper presents an update of existing technology and underscores the mechanisms that negatively impact the durability of posterior composite restorations in permanent teeth. PMID:23750102
D → π and D → K semileptonic form factors with Nf = 2 + 1 + 1 twisted mass fermions
Lubicz, Vittorio; Riggio, Lorenzo; Salerno, Giorgio; Simula, Silvano; Tarantino, Cecilia
2018-03-01
We present a lattice determination of the vector and scalar form factors of the D → π(K)lv semileptonic decays, which are relevant for the extraction of the CKM matrix elements |Vcd| and |Vcs| from experimental data. Our analysis is based on the gauge configurations produced by the European Twisted Mass Collaboration with Nf = 2 + 1 +1 flavors of dynamical quarks. We simulated at three different values of the lattice spacing and with pion masses as small as 210 MeV. The matrix elements of both vector and scalar currents are determined for a plenty of kinematical conditions in which parent and child mesons are either moving or at rest. Lorentz symmetry breaking due to hypercubic effects is clearly observed in the data and included in the decomposition of the current matrix elements in terms of additional form factors. After the extrapolations to the physical pion mass and to the continuum limit the vector and scalar form factors are determined in the whole kinematical region from q2 = 0 up to qmax2 = (MD - Mπ(K))2 accessible in the experiments, obtaining a good overall agreement with experiments, except in the region at high values of q2 where some deviations are visible.
Evolution of the global economic science as a factor of forming the expectations of economic agents
Directory of Open Access Journals (Sweden)
Valeriy Vladimirovich Shlychkov
2015-09-01
Full Text Available Objective to reveal the correlation between the level of economic system development and the adequacy of economic ideas and conceptions at particular historic periods to define the role of economic theory in generating economic knowledge and the degree of its influence on economic subjects39 behavior under permanent changes in technology setups and evolutionary development of economic systems. Methods the research methodology was based on ensuring the uniformity of logical and historical approaches the research methods were widely used descriptive analysis and synthesis deduction and induction generalization observation prediction scientific abstraction statistical analysis system analysis and techniques of grouping and classification methods of comparative historical and interdisciplinary analysis expert judgment the combination of these methods allowed to ensure the accuracy of the research and the validity of conclusions. Results the correlation was revealed between the level of economic system development and the adequacy of economic ideas and concepts at certain historical periods the significant role of economic theory in shaping the optimal behavior of economic entitieswas identified the purpose of the economic theory was statedass providing the evolutionary development of our civilization through the process of scientifictheoretical support of business activities of the society. Scientific novelty the main theoretical and methodological approaches were identified to the formation of economic agents expectations to obtain economic knowledge the trends are revealed of expansion and qualitative change of the range of issues facing economistsresearchers in the development of postindustrial society the authorsrsquo interpretation is proposed of the notion ldquoeconomic agentsrsquoexpectationrdquo in which public expectations of economic science are viewed as quotthe formed society need for scientifically grounded economic knowledgequot it
Topological invariants and the dynamics of an axial vector torsion field
International Nuclear Information System (INIS)
Drechsler, W.
1983-01-01
A generalized throry of gravitation is discussed which is based on a Riemann-Cartan space-time, U 4 , with an axial vector torsion field. Besides Einstein's equations determining the metric of the U 4 a system of nonlinear field equations is established coupling an axial vector source current to the axial vector torsion field. The properties of the solutions of these equations are discussed assuming a London-type condition relating the axial current and torsion field. To characterize the solutions use is made of the Euler and Pontrjagin forms and the associated quadratic curvature invariants for the U 4 space-time. It is found that there exists for a Riemann-Cartan space-time a relation between the zeros of the axial vector torsion field and the singularities of the Pontrjagin invariant, which is analogous to the well-known Hopf relation between the zeros of vector fields and the Euler characteristic. (author)
Posterior composite restoration update: focus on factors influencing form and function
Directory of Open Access Journals (Sweden)
Bohaty BS
2013-05-01
Full Text Available Brenda S Bohaty,1,2 Qiang Ye,3 Anil Misra,3,4 Fabio Sene,6 Paulette Spencer3,51Department of Pediatric Dentistry, University of Missouri-Kansas City School of Dentistry, Kansas City, MO, USA; 2Department of Pediatric Dentistry, Children's Mercy Hospital, Kansas City, MO, USA; 3Bioengineering Research Center, 4Department of Civil, Environmental, and Architectural Engineering, 5Department of Mechanical Engineering, University of Kansas, Lawrence, KS, USA; 6Department of Restorative Dentistry, State University of Londrina, School of Dentistry, Londrina, BrazilAbstract: Restoring posterior teeth with resin-based composite materials continues to gain popularity among clinicians, and the demand for such aesthetic restorations is increasing. Indeed, the most common aesthetic alternative to dental amalgam is resin composite. Moderate to large posterior composite restorations, however, have higher failure rates, more recurrent caries, and increased frequency of replacement. Investigators across the globe are researching new materials and techniques that will improve the clinical performance, handling characteristics, and mechanical and physical properties of composite resin restorative materials. Despite such attention, large to moderate posterior composite restorations continue to have a clinical lifetime that is approximately one-half that of the dental amalgam. While there are numerous recommendations regarding preparation design, restoration placement, and polymerization technique, current research indicates that restoration longevity depends on several variables that may be difficult for the dentist to control. These variables include the patient's caries risk, tooth position, patient habits, number of restored surfaces, the quality of the tooth–restoration bond, and the ability of the restorative material to produce a sealed tooth–restoration interface. Although clinicians tend to focus on tooth form when evaluating the success and failure of
Health and imaging outcomes in axial spondyloarthritis
Machado, P.M.
2016-01-01
This thesis focuses on the assessment and monitoring of health and imaging outcomes in axial spondyloarthritis (SpA) and the relationship between these outcomes. Four major contributions to the understanding and management of axial SpA were made: 1) the improvement and facilitation of the assessment
Aryabhata and Axial Rotation of Earth
Indian Academy of Sciences (India)
GENERAL I ARTICLE. Aryabhata and Axial Rotation of Earth. 3. A Brief History. Amartya Kumar Datta is in the Stat-Math Unit of. Indian Statistic.llnstiutte,. Kolkata. His research ... historical account of some of Aryabha~a's views on axial rotation of Earth, ..... and stress on periodic observations and updating of the parameters.
Soil carbon distribution in Alaska in relation to soil-forming factors
Johnson, K.D.; Harden, J.; McGuire, A.D.; Bliss, N.B.; Bockheim, James G.; Clark, M.R.; Nettleton-Hollingsworth, T.; Jorgenson, M.T.; Kane, E.S.; Mack, M.; O'Donnell, J.; Ping, C.-L.; Schuur, E.A.G.; Turetsky, M.R.; Valentine, D.W.
2011-01-01
The direction and magnitude of soil organic carbon (SOC) changes in response to climate change remain unclear and depend on the spatial distribution of SOC across landscapes. Uncertainties regarding the fate of SOC are greater in high-latitude systems where data are sparse and the soils are affected by sub-zero temperatures. To address these issues in Alaska, a first-order assessment of data gaps and spatial distributions of SOC was conducted from a recently compiled soil carbon database. Temperature and landform type were the dominant controls on SOC distribution for selected ecoregions. Mean SOC pools (to a depth of 1-m) varied by three, seven and ten-fold across ecoregion, landform, and ecosystem types, respectively. Climate interactions with landform type and SOC were greatest in the uplands. For upland SOC there was a six-fold non-linear increase in SOC with latitude (i.e., temperature) where SOC was lowest in the Intermontane Boreal compared to the Arctic Tundra and Coastal Rainforest. Additionally, in upland systems mineral SOC pools decreased as climate became more continental, suggesting that the lower productivity, higher decomposition rates and fire activity, common in continental climates, interacted to reduce mineral SOC. For lowland systems, in contrast, these interactions and their impacts on SOC were muted or absent making SOC in these environments more comparable across latitudes. Thus, the magnitudes of SOC change across temperature gradients were non-uniform and depended on landform type. Additional factors that appeared to be related to SOC distribution within ecoregions included stand age, aspect, and permafrost presence or absence in black spruce stands. Overall, these results indicate the influence of major interactions between temperature-controlled decomposition and topography on SOC in high-latitude systems. However, there remains a need for more SOC data from wetlands and boreal-region permafrost soils, especially at depths > 1 m in
International Nuclear Information System (INIS)
Ghayesh, Mergen H.; Amabili, Marco; Farokhi, Hamed
2013-01-01
In the present study, the coupled nonlinear dynamics of an axially moving viscoelastic beam with time-dependent axial speed is investigated employing a numerical technique. The equations of motion for both the transverse and longitudinal motions are obtained using Newton’s second law of motion and the constitutive relations. A two-parameter rheological model of the Kelvin–Voigt energy dissipation mechanism is employed in the modelling of the viscoelastic beam material, in which the material time derivative is used in the viscoelastic constitutive relation. The Galerkin method is then applied to the coupled nonlinear equations, which are in the form of partial differential equations, resulting in a set of nonlinear ordinary differential equations (ODEs) with time-dependent coefficients due to the axial acceleration. A change of variables is then introduced to this set of ODEs to transform them into a set of first-order ordinary differential equations. A variable step-size modified Rosenbrock method is used to conduct direct time integration upon this new set of first-order nonlinear ODEs. The mean axial speed and the amplitude of the speed variations, which are taken as bifurcation parameters, are varied, resulting in the bifurcation diagrams of Poincaré maps of the system. The dynamical characteristics of the system are examined more precisely via plotting time histories, phase-plane portraits, Poincaré sections, and fast Fourier transforms (FFTs)
Lungfish axial muscle function and the vertebrate water to land transition.
Directory of Open Access Journals (Sweden)
Angela M Horner
Full Text Available The role of axial form and function during the vertebrate water to land transition is poorly understood, in part because patterns of axial movement lack morphological correlates. The few studies available from elongate, semi-aquatic vertebrates suggest that moving on land may be powered simply from modifications of generalized swimming axial motor patterns and kinematics. Lungfish are an ideal group to study the role of axial function in terrestrial locomotion as they are the sister taxon to tetrapods and regularly move on land. Here we use electromyography and high-speed video to test whether lungfish moving on land use axial muscles similar to undulatory swimming or demonstrate novelty. We compared terrestrial lungfish data to data from lungfish swimming in different viscosities as well as to salamander locomotion. The terrestrial locomotion of lungfish involved substantial activity in the trunk muscles but almost no tail activity. Unlike other elongate vertebrates, lungfish moved on land with a standing wave pattern of axial muscle activity that closely resembled the pattern observed in terrestrially locomoting salamanders. The similarity in axial motor pattern in salamanders and lungfish suggests that some aspects of neuromuscular control for the axial movements involved in terrestrial locomotion were present before derived appendicular structures.
Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor
Energy Technology Data Exchange (ETDEWEB)
Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others
1997-04-01
Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.
Rawat, Roopa; Agrawal, Neha; Patil, Nilesh S.
2017-01-01
Since 1984 the diagnosis of ankylosing spondylitis (AS) has been based upon the modified New York (mNY) criteria with mandatory presence of radiographic sacroiliitis, without which the diagnosis is not tenable. However, it may take years or decades for radiographic sacroiliitis to develop delaying the diagnosis for long periods. It did not matter in the past because no effective treatment was available. However, with the availability of a highly effective treatment, namely, tumour necrosis factor-α inhibitors (TNFi), the issue of early diagnosis of AS acquired an urgency. The Assessment of SpondyloArthritis International Society (ASAS) classification criteria published in 2009 was a significant step towards this goal. These criteria described an early stage of the disease where sacroiliitis was demonstrable only on MRI but not on standard radiograph. Therefore, this stage of the disease was labelled “nonradiographic axial SpA” (nr-axSpA). But questions have been raised if, in search of early diagnosis, specificity was compromised. The Federal Drug Administration (FDA, USA) withheld approval for the use of TNFi in patients with nr-axSpA because of issues related to the specificity of these criteria. This review attempts to clarify some of these aspects of the nr-axSpA-AS relationship and also tries to answer the question whether ASAS classifiable radiographic axial spondyloarthritis (r-axSpA) term can be interchangeably used with the term AS. PMID:28555158
Directory of Open Access Journals (Sweden)
Ana María Camacho
2016-09-01
Full Text Available Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs. The results show that for small reductions (rh < 20%, the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%, it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.
The effects of density-dependent form factors for (e, e'p) reaction in quasi-elastic region
Energy Technology Data Exchange (ETDEWEB)
Kim, K.S. [Korea Aerospace University, School of Liberal Arts and Science, Goyang (Korea, Republic of); Cheoun, Myung-Ki [Soongsil University, Department of Physics, Seoul (Korea, Republic of); Kim, Hungchong [Kookmin University, Department of General Education, Seoul (Korea, Republic of); So, W.Y. [Kangwon National University at Dogye, Department of Radiological Science, Samcheok (Korea, Republic of)
2016-04-15
Within the framework of a relativistic single particle model, the effects of density-dependent electromagnetic form factors on the exclusive (e, e'p) reaction are investigated in the quasi-elastic region. The density-dependent electromagnetic form factors are generated from a quark-meson coupling model and used to calculate the cross sections in two different densities, either at the normal density of ρ{sub 0} ∝ 0.15 fm{sup -3} or at the lower density, 0.5ρ{sub 0}. Then these cross sections are analyzed in the two different kinematics: One is that the momentum of the outgoing nucleon is along the momentum transfer. The other is that the angle between the momentum of the outgoing nucleon and the momentum transfer is varied at fixed magnitude of the momentum of the outgoing nucleon. Our theoretical differential reduced cross sections are compared with the NIKHEF data for the {sup 208}Pb(e, e'p) reaction, which is related to the probability that a bound nucleon from a given orbit can be knocked-out of the nucleus. The effects of the density-dependent form factors increase the differential cross sections for both knocked-out proton and neutron by an amount of a few percent. Moreover they are shown to be almost the same within only a few percent, i.e., nearly independent of the shell location of knockout nucleons. These results are quite consistent with the characteristics of double magic nuclei which have relatively sharp smearing in the density distribution. (orig.)
Xiang, Yang; Yan, Chao; Guo, Xiaolong; Zhou, Kaifeng; Li, Sheng'an; Gao, Qian; Wang, Xuan; Zhao, Feng; Liu, Jie; Lee, Wen-Hui; Zhang, Yun
2014-05-06
Aerolysins are virulence factors belonging to the bacterial β-pore-forming toxin superfamily. Surprisingly, numerous aerolysin-like proteins exist in vertebrates, but their biological functions are unknown. βγ-CAT, a complex of an aerolysin-like protein subunit (two βγ-crystallin domains followed by an aerolysin pore-forming domain) and two trefoil factor subunits, has been identified in frogs (Bombina maxima) skin secretions. Here, we report the rich expression of this protein, in the frog blood and immune-related tissues, and the induction of its presence in peritoneal lavage by bacterial challenge. This phenomena raises the possibility of its involvement in antimicrobial infection. When βγ-CAT was administrated in a peritoneal infection model, it greatly accelerated bacterial clearance and increased the survival rate of both frogs and mice. Meanwhile, accelerated Interleukin-1β release and enhanced local leukocyte recruitments were determined, which may partially explain the robust and effective antimicrobial responses observed. The release of interleukin-1β was potently triggered by βγ-CAT from the frog peritoneal cells and murine macrophages in vitro. βγ-CAT was rapidly endocytosed and translocated to lysosomes, where it formed high molecular mass SDS-stable oligomers (>170 kDa). Lysosomal destabilization and cathepsin B release were detected, which may explain the activation of caspase-1 inflammasome and subsequent interleukin-1β maturation and release. To our knowledge, these results provide the first functional evidence of the ability of a host-derived aerolysin-like protein to counter microbial infection by eliciting rapid and effective host innate immune responses. The findings will also largely help to elucidate the possible involvement and action mechanisms of aerolysin-like proteins and/or trefoil factors widely existing in vertebrates in the host defense against pathogens.
Deuteron form factors and e-d polarization observables for the Paris and Graz-II potentials
International Nuclear Information System (INIS)
Schwarz, K.; Plessas, W.; Mathelitsch, L.
1983-01-01
Elastic e-d scattering is studied employing the meson-theoretical Paris potential and the non-local separable Graz-II potential. Electric and magnetic form factors are calculated with inclusion of meson-exchange currents and compared to existing experimental data. Deuteron vector and tensor polarizations are predicted and discussed in relation to the deuteron wave functions of the potential models considered. Thereby the off-shell behaviour of the Graz-II interaction is found to be close to that one of the Paris potential over the most important domain of low and moderate off-shell moments. (Author)
International Nuclear Information System (INIS)
Rekalo, M.P.; Tomasi-Gustafsson, E.
1996-01-01
We analyze the properties of the inclusive d + p-reactions, with particular interest in the domain of nucleonic resonances excitation. The calculated cross section and polarization observables show that it is possible to disentangle the different reaction mechanisms (ω-,σ-, n- exchange) and bring new information about the electromagnetic form factors of the deuteron as well as of the nucleonic resonances excitation. Existing data on the tensor analyzing power are in agreement with the predictions based on the ω-exchange model. (authors)
Determination of the pion charge form factor for Q2 = 0.60-1.60 (GeV/c)2
International Nuclear Information System (INIS)
Vardan Tadevosyan; Henk Blok; Garth Huber; David Abbott; Heinz Anklin; Christopher Armstrong; John Arrington; Ketevi Assamagan; Steven Avery; O. Baker; C. Bochna; Edward Brash; Herbert Breuer; Nicholas Chant; James Dunne; T. Eden; Rolf Ent; David Gaskell; Ronald Gilman; Kenneth Gustafsson; Wendy Hinton; Harold Jackson; Mark Jones; Cynthia Keppel; Pyunghun Kim; Wooyoung Kim; Andreas Klein; Douglas Koltenuk; Meihua Liang; George Lolos; Allison Lung; David Mack; David McKee; David Meekins; Joseph Mitchell; Hamlet Mkrtchyan; Robert Mueller; Gabriel Niculescu; Maria-Ioana Niculescu; David Pitz; David Potterveld; Liming Qin; Joerg Reinhold; Ilkyoung Shin; Stepan Stepanyan; Liguang Tang; Rob van der Meer; Kelley Vansyoc; D. Van Westrum; Jochen Volmer; William Vulcan; Stephen Wood; Chen Yan; Wenxia Zhao; Benedikt Zihlmann
2006-01-01
The data analysis for the reaction H(e,e(prime) pi + )n, which was used to determine values for the charged pion form factor Fpi for values of Q2 = 0.6-1.6 (gEv/C) 2 , has been repeated with careful inspection of all steps and special attention to systematic uncertainties. Also the method used to extract Fpi from the measured longitudinal cross section was critically reconsidered. Final values for the separated longitudinal and transverse cross sections and the extracted values of Fpi are presented
Form factors of the semileptonic decays B(D) → π + lν near zero recoil
International Nuclear Information System (INIS)
Jin Hongying.
1995-12-01
We discuss the possible corrections of some recent calculations on the form factors which parametrize the matrix element of the decays B(D) → πlν. These calculations are based on the assumption that the B * (D * ) pole contribution is fully dominant near the zero recoil. By using the Bethe-Salpeter approach. We have calculated some low-lying states pole terms predicted by the quark model. The numerical results are obtained to the next-leading order of the 1/M expansion. (author). 12 refs, 1 tab
Energy Technology Data Exchange (ETDEWEB)
Rekalo, M.P.; Tomasi-Gustafsson, E.
1996-12-31
We analyze the properties of the inclusive d + p-reactions, with particular interest in the domain of nucleonic resonances excitation. The calculated cross section and polarization observables show that it is possible to disentangle the different reaction mechanisms ({omega}-,{sigma}-, n- exchange) and bring new information about the electromagnetic form factors of the deuteron as well as of the nucleonic resonances excitation. Existing data on the tensor analyzing power are in agreement with the predictions based on the {omega}-exchange model. (authors). 18 refs.