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Sample records for nlo dglap evolution

  1. Implementing NLO DGLAP evolution in Parton Showers

    Energy Technology Data Exchange (ETDEWEB)

    Höche, Stefan [SLAC; Krauss, Frank [Durham U., IPPP; Prestel, Stefan [Fermilab

    2017-05-02

    We present a parton shower which implements the DGLAP evolution of parton densities and fragmentation functions at next-to-leading order precision up to effects stemming from local four-momentum conservation. The Monte-Carlo simulation is based on including next-to-leading order collinear splitting functions in an existing parton shower and combining their soft enhanced contributions with the corresponding terms at leading order. Soft double counting is avoided by matching to the soft eikonal. Example results from two independent realizations of the algorithm, implemented in the two event generation frameworks Pythia and Sherpa, illustrate the improved precision of the new formalism.

  2. Decoupling the NLO coupled QED $\\otimes$ QCD, DGLAP evolution equations,Using Laplace Transform Method

    CERN Document Server

    Mottaghizadeh, Marzieh; Taghavi-Shahri, Fatemeh

    2016-01-01

    We analytically solved the QED $\\otimes$ QCD coupled DGLAP evolution equations at leading order (LO) quantum electrodynamics (QED) and next to leading order (NLO) quantum chromodynamics (QCD) approximations, using the Laplace transform method and then computed the proton structure function in terms of the unpolarized parton distributions functions. Our analyitical solutions for parton densities are in good agreement with those from APFEL (A PDF Evolution Library) (Computer Physics Communications 185, 1647-1668 (2014)) and CT14QED (Phys. Rev. D 93, 114015 (2016)) global parameterizations. We also compared the proton structure function, $F_{2}^{p}(x,Q^{2})$, with experimental data released by the ZEUS and H1 collaborations at HERA. There is a nice agreement between them in the range of low and high x and $Q^{2}$.

  3. Analytical solutions of the QCD⊗QED DGLAP evolution equations based on the Mellin transform technique in NLO approximation

    Science.gov (United States)

    Mottaghizadeh, Marzieh; Taghavi Shahri, Fatemeh; Eslami, Parvin

    2017-10-01

    In this paper we present a new and efficient analytical solutions for evolving the QCD⊗QED DGLAP evolution equations in Mellin space and obtain the parton distribution functions (PDFs) in perturbative QCD including the QED corrections. The validity of our analytical solutions, which have done in the next to leading order QCD and the leading order QED approximations, are checked with the initial parton distributions from newly released CT14QED global analysis code (Schmidt et al., 2016 [9]). The evolved parton distribution functions are in good agreement with CT14QED PDFs set and also with those from APFEL (Bertone et al., 2014 [7]) program. Finally, we derived the impact of the NLO QED corrections to the QCD⊗QED DGLAP evolution equations.

  4. Solution of QCD⊗QED coupled DGLAP equations at NLO

    Science.gov (United States)

    Zarrin, S.; Boroun, G. R.

    2017-09-01

    In this work, we present an analytical solution for QCD⊗QED coupled Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations at the leading order (LO) accuracy in QED and next-to-leading order (NLO) accuracy in perturbative QCD using double Laplace transform. This technique is applied to obtain the singlet, gluon and photon distribution functions and also the proton structure function. We also obtain contribution of photon in proton at LO and NLO at high energy and successfully compare the proton structure function with HERA data [1] and APFEL results [2]. Some comparisons also have been done for the singlet and gluon distribution functions with the MSTW results [3]. In addition, the contribution of photon distribution function inside the proton has been compared with results of MRST [4] and with the contribution of sea quark distribution functions which obtained by MSTW [3] and CTEQ6M [5].

  5. Interplay of IR-Improved DGLAP-CS Theory and NLO Parton Shower MC Precision

    CERN Document Server

    Ward, B F L; Yost, S A

    2013-01-01

    We present the interplay between the new IR-improved DGLAP-CS theory and the precision of NLO parton shower/ME matched MC`s as it is realized by the new MC Herwiri1.031 in interface to MC@NLO. We discuss phenomenological implications using comparisons with recent LHC data on single heavy gauge boson production.

  6. Unpolarized coupled DGLAP evolution equation at small-

    Indian Academy of Sciences (India)

    Saurav Bhattacharjee; Ranjit Baishya; Jayanata Kumar Sarma

    2013-01-01

    In this paper, we have obtained the solution of the unpolarized coupled Dokshitzer–Gribove–Lipatov–Alterelli–Parisi (DGLAP) evolution equation in leading order at the small- limit. Here, we have used a Taylor series expansion, separation of functions and then the method of characteristics to solve the evolution equations. We have also calculated -evolution of singlet and gluon distribution functions and the results are compared with E665 and NNPDF data for singlet structure function and GRV1998 and MRST2004 gluon parametrizations. It is shown that our results are in good agreement with the parametrizations especially at small-x and high-2 region. From global parametrizations and our results, we have seen that the singlet and gluon distribution functions increase when 2 increases for fixed values of .

  7. NLO JIMWLK evolution unabridged

    CERN Document Server

    Kovner, Alex; Mulian, Yair

    2014-01-01

    In Ref. [1] we presented the JIMWLK Hamiltonian for high energy evolution of QCD amplitudes at the next-to-leading order accuracy in $\\alpha_s$. In the present paper we provide details of our original derivation, which was not reported in [1], and provide the Hamiltonian in the form appropriate for action on color singlet as well as color nonsinglet states. The rapidity evolution of the quark dipole generated by this Hamiltonian is computed and compared with the corresponding result of Balitsky and Chirilli [2]. We then establish the equivalence between the NLO JIMWLK Hamiltonian and the NLO version of the Balitsky's hierarchy [3], which includes action on nonsinglet combinations of Wilson lines. Finally, we present complete evolution equation for three-quark Wilson loop operator, thus extending the results of Grabovsky [4].

  8. Gluon distributions from Oliveira-Martin-Ryskin combined BFKL+DGLAP evolution equations

    CERN Document Server

    Toton, Dawid

    2014-01-01

    Kwiecinski, Martin, Stasto [13] argue for inclusion of DGLAP terms into BFKL evolution of unintegrated gluon density. The equation was reformulated by Oliveira, Martin, Ryskin [6] employing the opening angle {\\theta} = k/xp as the evolution variable. It leads to a description of a {\\theta}-integrated gluon density. This paper is a numerical study of these two similar combined BFKL+DGLAP formulations. It is a demonstration of feasibility of the new approach. The different ways of subtracting the contribution common for BFKL and DGLAP proposed in [13] and [6] are compared. The numerical tests confirm that the {\\theta} variable is a more natural evolution variable for this kind of equation.

  9. The next-to-leading order (NLO) gluon distribution from DGLAP equation and the logarithmic derivatives of the proton structure function 2 (, 2) at low

    Indian Academy of Sciences (India)

    D K Choudhury; P K Sahariah

    2005-08-01

    At low , an analytic solution of the DGLAP equation for gluon in the next-to-leading order (NLO) is obtained by applying the method of characteristics. Its compatibility with double leading logarithmic approximation (DLLA) asymptotics is discussed and comparison with the exact ones like GRV98NLO is made. The solution is then utilized to calculate the derivatives $\\dfrac{ 2 (x, 2)}{ {\\text{ln}} 2}$ and $\\dfrac{ {\\text{ln}} 2 (x, 2)}{ {\\text{ln}} (1/x)}$ and compared with the recent HERA data. Our solution is found to reproduce most of the essential features of the data on the derivatives.

  10. Phenomenological study of the interplay between IR-improved DGLAP-CS theory and the precision of an NLO ME matched parton shower MC

    Energy Technology Data Exchange (ETDEWEB)

    Majhi, S.K., E-mail: tpskm@iacs.res.in [Indian Association for the Cultivation of Science, Kolkata (India); Mukhopadhyay, A., E-mail: aditi_mukhopadhyay@baylor.edu [Baylor University, Waco, TX (United States); Ward, B.F.L., E-mail: bfl_ward@baylor.edu [Baylor University, Waco, TX (United States); Yost, S.A., E-mail: scott.yost@citadel.edu [The Citadel, Charleston, SC (United States)

    2014-11-15

    We present a phenomenological study of the current status of the application of our approach of exact amplitude-based resummation in quantum field theory to precision QCD calculations, by realistic MC event generator methods, as needed for precision LHC physics. We discuss recent results as they relate to the interplay of the attendant IR-improved DGLAP-CS theory of one of us and the precision of exact NLO matrix-element matched parton shower MC’s in the Herwig6.5 environment as determined by comparison to recent LHC experimental observations on single heavy gauge boson production and decay. The level of agreement between the new theory and the data continues to be a reason for optimism. In the spirit of completeness, we discuss as well other approaches to the same theoretical predictions that we make here from the standpoint of physical precision with an eye toward the (sub-)1% QCD⊗EW total theoretical precision regime for LHC physics. - Highlights: • Using LHC data, we show that IR-improved DGLAP-CS kernels with exact NLO Shower/ME matching improves MC precision. • We discuss other possible approaches in comparison with ours. • We propose experimental tests to discriminate between competing approaches.

  11. Non-singlet structure functions: Combining the leading logarithms resummation at small-x with DGLAP

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2005-01-01

    The explicit expressions for the non-singlet DIS structure functions obtained at small x by resumming the most singular logarithmic contributions are discussed and compared in detail with the DGLAP evolution for different values of x and Q^2. The role played by the initial conditions for the parton densities currently used in the DGLAP analysis, on the small-$x$ behavior of the non-singlet structure functions is discussed. Explicit expressions are presented which implement the NLO DGLAP contributions with our small-x results.

  12. Phenomenological Study of the Interplay between IR-Improved DGLAP-CS Theory and the Precision of an NLO ME Matched Parton Shower MC

    CERN Document Server

    Mukhopadhyay, A; Yost, S A

    2013-01-01

    We present a phenomenological study of the current status of the application of our approach of {\\it exact} amplitude-based resummation in quantum field theory to precision QCD calculations, by realistic MC event generator methods, as needed for precision LHC physics. We discuss recent results as they relate to the interplay of the attendant IR-Improved DGLAP-CS theory of one of us and the precision of exact NLO matrix-element matched parton shower MC's in the Herwig6.5 environment as determined by comparison to recent LHC experimental observations on single heavy gauge boson production and decay. The level of agreement between the new theory and the data continues to be a reason for optimism. In the spirit of completeness, we discuss as well other approaches to the same theoretical predictions that we make here from the standpoint of physical precision with an eye toward the (sub-)1% QCD \\otimes EW total theoretical precision regime for LHC physics.

  13. A Matrix Approach to Numerical Solution of the DGLAP Evolution Equations

    CERN Document Server

    Ratcliffe, P G

    2001-01-01

    A matrix-based approach to numerical integration of the DGLAP evolution equations is presented. The method arises naturally on discretisation of the Bjorken x variable, a necessary procedure for numerical integration. Owing to peculiar properties of the matrices involved, the resulting equations take on a particularly simple form and may be solved in closed analytical form in the variable t=ln(alpha_0/alpha). Such an approach affords parametrisation via data x bins, rather than fixed functional forms. Thus, with the aid of the full correlation matrix, appraisal of the behaviour in different x regions is rendered more transparent and free of pollution from unphysical cross-correlations inherent to functional parametrisations. Computationally, the entire programme results in greater speed and stability; the matrix representation developed is extremely compact. Moreover, since the parameter dependence is linear, fitting is very stable and may be performed analytically in a single pass over the data values.

  14. Non-singlet structure functions: Combining the leading logarithms resummation at small-x with DGLAP

    Energy Technology Data Exchange (ETDEWEB)

    Ermolaev, B.I. [Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation)]. E-mail: ermolaev@mail.cern.ch; Greco, M. [Department of Physics and INFN, University Rome III, Rome (Italy); Troyan, S.I. [St. Petersburg Institute of Nuclear Physics, 188300 Gatchina (Russian Federation)

    2005-08-25

    The explicit expressions for the non-singlet DIS structure functions F{sub 1} and g{sub 1}, obtained at small-x by resumming the leading logarithmic contributions to all orders, are discussed and compared in detail with the DGLAP evolution for different values of x and Q{sup 2}. The role played by the DGLAP inputs for the initial parton densities on the small-x behavior of the non-singlet structure functions is discussed. It is shown that the singular factors included into the fits ensure the Regge asymptotics of the non-singlet structure functions and mimic the impact of the total resummation of the leading logarithms found explicitly in our approach. Explicit expressions are presented which implement the NLO DGLAP contributions with our small-x results.

  15. The Green function for the BFKL pomeron and the transition to DGLAP evolution

    Science.gov (United States)

    Kowalski, H.; Lipatov, L. N.; Ross, D. A.

    2014-06-01

    We consider the (process-independent) Green function for the BFKL equation with running coupling, and explain how, within the semi-classical approximation, it is related to Green function of the Airy equation. The unique Green function is obtained from a combination of its required ultraviolet behaviour compatible with asymptotic freedom and an infrared limit phase imposed by the non-perturbative sector of QCD. We show that at sufficiently large gluon transverse momenta the corresponding gluon density matches that of the DGLAP analysis, whereas for relatively small values of the gluon transverse momentum the gluon distribution is sensitive to the Regge poles, whose positions are determined both by the non-perturbative QCD dynamics and physics at large transverse momenta.

  16. The Green Function for the BFKL Pomeron and the Transition to DGLAP Evolution

    CERN Document Server

    Kowalski, Henri; Ross, Douglas

    2014-01-01

    We consider the (process-independent) Green function for the BFKL equation in the next-to-leading order approximation, with running coupling, and explain how, within the semi-classical approximation, it is related to Green function of the Airy equation. The unique Green function is obtained from a combination of its required ultraviolet behaviour compatible with asymptotic freedom and an infrared limit phase imposed by the non-perturbative sector of QCD. We show that at sufficiently large gluon transverse momenta the corresponding gluon density matches that of the DGLAP analysis, whereas for relatively small values of the gluon transverse momentum the gluon distribution is sensitive to the Regge poles, whose positions are determined both by the non-pertubative QCD dynamics and physics at large transverse momenta.

  17. An analytic solution to LO coupled DGLAP evolution equations: a new pQCD tool

    CERN Document Server

    Block, Martin M; Ha, Phuoc; McKay, Douglas W

    2010-01-01

    We have analytically solved the LO pQCD singlet DGLAP equations using Laplace transform techniques. Newly-developed highly accurate numerical inverse Laplace transform algorithms allow us to write fully decoupled solutions for the singlet structure function F_s(x,Q^2)and G(x,Q^2) as F_s(x,Q^2)={\\cal F}_s(F_{s0}(x), G_0(x)) and G(x,Q^2)={\\cal G}(F_{s0}(x), G_0(x)). Here {\\cal F}_s and \\cal G are known functions of the initial boundary conditions F_{s0}(x) = F_s(x,Q_0^2) and G_{0}(x) = G(x,Q_0^2), i.e., the chosen starting functions at the virtuality Q_0^2. For both G and F_s, we are able to either devolve or evolve each separately and rapidly, with very high numerical accuracy, a computational fractional precision of O(10^{-9}). Armed with this powerful new tool in the pQCD arsenal, we compare our numerical results from the above equations with the published MSTW2008 and CTEQ6L LO gluon and singlet F_s distributions, starting from their initial values at Q_0^2=1 GeV^2 and 1.69 GeV^2, respectively, using their ...

  18. Balitsky-JIMWLK evolution equation at NLO

    Directory of Open Access Journals (Sweden)

    Chirilli Giovanni Antonio

    2014-01-01

    Full Text Available Wilson line operators are infinite gauge factors ordered along the straight lines of the fast moving particles. Scattering amplitudes of proton-Nucleus or Nucleus-Nucleus collisions at high-energy are written in terms of matrix elements of these operators and the energy dependence of such amplitudes is obtained by the evolution equation with respect to the rapidity parameter: the Balitsky-JIMWLK evolution equation. A brief description of the derivation of the Balitsky-JIMWLK evolution equation at leading order and nextto-leading order will be presented.

  19. Medium-modified DGLAP evolution of fragmentation functions from large to small x

    Energy Technology Data Exchange (ETDEWEB)

    Albino, S.; Kniehl, B.A.; Perez-Ramos, R. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2009-03-15

    The unified description of fragmentation function evolution from large to small x which was developed for the vacuum in previous publications is now generalized to the medium, and is studied for the case in which the complete contribution from the largest class of soft gluon logarithms, the double logarithms, are accounted for and with the fixed order part calculated to leading order. In this approach it proves possible to choose the remaining degrees of freedom related to the medium such that the distribution of produced hadrons is suppressed at large momenta while the production of soft radiation-induced charged hadrons at small momenta is enhanced, in agreement with experiment. Just as for the vacuum, our approach does not require further assumptions concerning fragmentation and is more complete than previous computations of evolution in the medium. (orig.)

  20. Regge-like initial input and evolution of non-singlet structure functions from DGLAP equation up to next-next-to-leading order at low and low 2

    Indian Academy of Sciences (India)

    Nayan Mani Nath; Mrinal Kumar Das; Jayanta Kumar Sarma

    2015-10-01

    This is an attempt to study how the features of Regge theory, along with QCD predictions, lead towards the understanding of unpolarized non-singlet structure functions $F_{2}^{\\text{NS}}$ (, 2) and 3 (, 2) at low and low 2 . Combining the features of perturbative quantum chromodynamics (pQCD) and Regge theory, an ansatz for $F_{2}^{\\text{NS}}$ (, 2) and 3 (, 2) structure functions at small was obtained, which when used as the initial input to Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) equation, gives the 2 evolution of the non-singlet structure functions. The non-singlet structure functions, evolved in accordance with DGLAP evolution equations up to next-next-to-leading order are studied phenomenologically in comparison with the available experimental and parametrization results taken from NMC, CCFR, NuTeV, CORUS, CDHSW, NNPDF and MSTW Collaborations and a very good agreement is observed in this regard.

  1. Regge behaviour of distribution functions and evolution of gluon distribution function in next-to-leading order at low-x

    Indian Academy of Sciences (India)

    U Jamil; J K Sarma

    2008-09-01

    Evolution of gluon distribution function from Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) evolution equation in next-to-leading order (NLO) at low- is presented assuming the Regge behaviour of quark and gluon at this limit. We compare our results of gluon distribution function with MRST2004, GRV98LO and GRV98NLO parametrizations and show the compatibility of Regge behaviour of quark and gluon distribution functions with perturbative quantum chromodynamics (PQCD) at low-.

  2. On the dependence of QCD splitting functions on the choice of the evolution variable

    CERN Document Server

    Jadach, S; Placzek, W; Skrzypek, M

    2016-01-01

    We show that already at the NLO level the DGLAP evolution kernel Pqq starts to depend on the choice of the evolution variable. We give an explicit example of such a variable, namely the maximum of transverse momenta of emitted partons and we identify a class of evolution variables that leave the NLO Pqq kernel unchanged with respect to the known standard MS-bar results. The kernels are calculated using a modified Curci-Furmanski-Petronzio method which is based on a direct Feynman-graphs calculation.

  3. On the dependence of QCD splitting functions on the choice of the evolution variable

    Science.gov (United States)

    Jadach, S.; Kusina, A.; Placzek, W.; Skrzypek, M.

    2016-08-01

    We show that already at the NLO level the DGLAP evolution kernel P qq starts to depend on the choice of the evolution variable. We give an explicit example of such a variable, namely the maximum of transverse momenta of emitted partons and we identify a class of evolution variables that leave the NLO P qq kernel unchanged with respect to the known standard overline{MS} results. The kernels are calculated using a modified Curci-Furmanski-Petronzio method which is based on a direct Feynman-graphs calculation.

  4. Quark loop contribution to BFKL evolution: Running coupling and leading-N_f NLO intercept

    CERN Document Server

    Kovchegov, Yu V; Kovchegov, Yuri V.; Weigert, Heribert

    2006-01-01

    We study the sea quark contribution to the BFKL kernel in the framework of Mueller's dipole model using the results of our earlier calculation. We first obtain the BFKL equation with the running coupling constant. We observe that the ``triumvirate'' structure of the running coupling found previously for non-linear evolution equations in is preserved for the BFKL equation. In fact, we rederive the equation conjectured by Levin and by Braun, albeit for the unintegrated gluon distribution with a slightly unconventional normalization. We obtain the leading-N_f contribution to the NLO BFKL kernel in transverse momentum space and use it to calculate the leading-N_f contribution to the NLO BFKL pomeron intercept for the unintegrated gluon distribution. Our result agrees with the well-known results of Camici and Ciafaloni and of Fadin and Lipatov. We show how to translate this intercept to the case of the quark dipole scattering amplitude and find that it maps onto the expression found by Balitsky.

  5. Analytical solution to DGLAP integro-differential equation in a simple toy-model with a fixed gauge coupling

    CERN Document Server

    Alvarez, Gustavo; Kniehl, Bernd A; Kondrashuk, Igor; Parra-Ferrada, Ivan

    2016-01-01

    We consider a simple model for QCD dynamics in which DGLAP integro-differential equation may be solved analytically. This is a gauge model which possesses dominant evolution of gauge boson (gluon) distribution and in which the gauge coupling does not run. This may be ${\\cal N} =4$ supersymmetric gauge theory with softly broken supersymmetry, other finite supersymmetric gauge theory with lower level of supersymmetry, or topological Chern-Simons field theories. We maintain only one term in the splitting function of unintegrated gluon distribution and solve DGLAP analytically for this simplified splitting function. The solution is found by use of the Cauchy integral formula. The solution restricts form of the unintegrated gluon distribution as function of transfer momentum and of Bjorken $x$. Then we consider an almost realistic splitting function of unintegrated gluon distribution as an input to DGLAP equation and solve it by the same method which we have developed to solve DGLAP equation for the toy-model. We ...

  6. A global DGLAP analysis of nuclear PDFs

    Science.gov (United States)

    Eskola, K. J.; Kolhinen, V. J.; Paukkunen, H.; Salgado, C. A.

    2008-05-01

    In this talk, we shortly report results from our recent global DGLAP analysis of nuclear parton distributions. This is an extension of our former EKS98-analysis improved with an automated χ2 minimization procedure and uncertainty estimates. Although our new analysis show no significant deviation from EKS98, a sign of a significantly stronger gluon shadowing could be seen in the RHIC BRAHMS data.

  7. Solution of QCD$\\otimes$QED coupled DGLAP equations

    CERN Document Server

    Zarrin, S

    2016-01-01

    In this work, we present an analytical solution for QCD$\\otimes$QED coupled Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations at the leading order accuracy using double Laplace transform. This technique is applied to obtain the singlet, gluon and photon distribution functions and also the proton structure function. We successfully compare the proton structure function with HERA data \\cite{12} and APFEL results \\cite{7}. Some comparisons also have been done for the singlet and gluon distribution functions with the MSTW results\\cite{9}. In addition, the contribution of photon distribution function inside the proton has been compared with results of MRST \\cite{11} and with the contribution of sea quark distribution functions which obtained by MSTW \\cite{9} and CTEQ6M \\cite{14}.

  8. Analytical solution to DGLAP integro-differential equation in a simple toy-model with a fixed gauge coupling

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Gustavo [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Concepcion Univ. (Chile). Dept. de Fisica; Cvetic, Gorazd [Univ. Tecnica Federico Santa Maria, Valparaiso (Chile). Dept. de Fisica; Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Kondrashuk, Igor [Univ. del Bio-Bio, Chillan (Chile). Grupo de Matematica Aplicada; Univ. del Bio-Bio, Chillan (Chile). Grupo de Fisica de Altas Energias; Parra-Ferrada, Ivan [Talca Univ. (Chile). Inst. de Matematica y Fisica

    2016-11-15

    We consider a simple model for QCD dynamics in which DGLAP integro-differential equation may be solved analytically. This is a gauge model which possesses dominant evolution of gauge boson (gluon) distribution and in which the gauge coupling does not run. This may be N=4 supersymmetric gauge theory with softly broken supersymmetry, other finite supersymmetric gauge theory with lower level of supersymmetry, or topological Chern-Simons field theories. We maintain only one term in the splitting function of unintegrated gluon distribution and solve DGLAP analytically for this simplified splitting function. The solution is found by use of the Cauchy integral formula. The solution restricts form of the unintegrated gluon distribution as function of transfer momentum and of Bjorken x. Then we consider an almost realistic splitting function of unintegrated gluon distribution as an input to DGLAP equation and solve it by the same method which we have developed to solve DGLAP equation for the toy-model. We study a result obtained for the realistic gluon distribution and find a singular Bessel-like behaviour in the vicinity of the point x=0 and a smooth behaviour in the vicinity of the point x=1.

  9. High Energy QCD at NLO: from light-cone wave function to JIMWLK evolution

    CERN Document Server

    Lublinsky, Michael

    2016-01-01

    Soft components of the light cone wave-function of a fast moving projectile hadron is computed in perturbation theory to third order in QCD coupling constant. At this order, the Fock space of the soft modes consists of one-gluon, two-gluon, and a quark-antiquark states. The hard component of the wave-function acts as a non-Abelian background field for the soft modes and is represented by a valence charge distribution that accounts for non-linear density effects in the projectile. When scattered off a dense target, the diagonal element of the S-matrix reveals the Hamiltonian of high energy evolution, the JIMWLK Hamiltonian. This way we provide a new direct derivation of the JIMWLK Hamiltonian at the Next-to-Leading Order.

  10. Nuclear PDFs at NLO - status report and review of the EPS09 results

    CERN Document Server

    Eskola, K J; Salgado, C A

    2010-01-01

    We review the current status of the global DGLAP analysis of nuclear parton distribution functions, nPDFs, focusing on the recent EPS09 analysis, whose output, EPS09NLO, is the best-constrained NLO nPDF set on the market. Collinear factorization is found to work very well in the kinematical region studied. With the error sets released in the EPS09 package one can compute how the nPDF-related uncertainties propagate into factorizable nuclear hard-process cross sections. A comparison with the other existing NLO nPDF sets is shown, and the BRAHMS forward-$\\eta$ hadron data from d+Au collisions are discussed in the light of the EPS09 nPDFs and their error sets.

  11. NLO efforts in Herwig++

    CERN Document Server

    Reuschle, Christian; Gieseke, Stefan; Grellscheid, David; Plätzer, Simon; Rauch, Michael; Richardson, Peter; Schichtel, Peter; Seymour, Michael H; Siodmok, Andrzej; Wilcock, Alexandra; Fischer, Nadine; Harrendorf, Marco A; Nail, Graeme; Papaefstathiou, Andreas; Rauch, Daniel

    2016-01-01

    With the advent and recent extension of the BLHA standard to interface Monte Carlo event generators and one-loop matrix element providers, the Herwig++ event generator has expanded its range of applicability to a multitude of underlying hard processes at NLO QCD. The new NLO development is centered around the Matchbox framework, which turns fixed NLO QCD calculations into parton shower matched calculations - to be matched to the two parton shower variants of Herwig++. Matchbox provides thereby for the automated setup of the underlying fixed NLO QCD calculations and the interface to the one-loop matrix element providers, as well as for an efficient and automated multi-channel phase space sampling, and forms the basis for the NLO capabilities of the new release of Herwig++. Along with several other new features and developments, the new release marks the end of distinguishing Herwig++ and (Fortran) HERWIG, and constitutes the first major release of version 7 of the Herwig event generator.

  12. Tensor structure function b{sub 1}{sup d}(x,Q{sup 2}) of the deuteron at NLO and NNLO at small-x

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Saiful [R.G.I., Department of Physics, Assam, Guwahati (India); Choudhury, D.K. [Gauhati University, Department of Physics, Assam, Guwahati (India)

    2012-12-15

    The precision of the contemporary experimental data demands that the parton distribution functions (PDF's) should be corrected at least up to next-to-leading order (NLO) and preferably up to next-to-next-to-leading order (NNLO). A general form of tensor structure function b{sub 1}{sup d}(x,Q{sup 2}) of the deuteron at NLO and NNLO is obtained by using the solution of Dokshitzer, Gribov, Lipatov, Altarelli, Parisi (DGLAP) equation for singlet structure function at small-x. Results are compared with HERA Experiment data. (orig.)

  13. A solution of the DGLAP equation for gluon at low

    Indian Academy of Sciences (India)

    D K Choudhury; P K Sahariah

    2002-04-01

    We obtain a solution of the DGLAP equation for the gluon at low first by expanding the gluon in a Taylor series and then using the method of characteristics. We test its validity by comparing it with that of Glück, Reya and Vogt. The convergence criteria of the approximation used are also discussed. We also calculate 2(,2)/ ln 2 using its approximate relations with the gluon distribution at low . The predictions are then compared with the HERA data.

  14. Dynamical parton distributions from DGLAP equations with nonlinear corrections

    CERN Document Server

    Wang, Rong

    2016-01-01

    Determination of proton parton distribution functions is present under the dynamical parton model assumption by applying DGLAP equations with GLR-MQ-ZRS corrections. We provide two data sets, referred as IMParton16, which are from two different nonperturbative inputs. One is the naive three valence quarks input and the other is three valence quarks with flavor-asymmetric sea components input. Basically, both data sets are compatible with the experimental measurements at high scale ($Q^2>2$ GeV$^2$). Furthermore, our analysis shows that the input with flavor-asymmetric sea components better reproduce the structure functions at high $Q^2$. Generally, the obtained parton distribution functions, especially the gluon distribution functions, are the good options of inputs for simulations of high energy scattering processes. The analysis is performed under the fixed-flavor number scheme for $n_f=$ 3, 4, 5 and uses the $\\overline{\\text MS}$ scheme for the running coupling $\\alpha_s$ and the heavy-quark masses. Both d...

  15. Synthesis of DGLAP and total resummation of leading logarithms for the non-singlet spin structure function $g_{1}$

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2005-01-01

    The explicit expressions for the non-singlet DIS structure function g_1 at small $x$ are obtained by resumming the leading logarithmic contributions. The role played by the fits for the initial parton densities currently used in the DGLAP on the small-x behavior of the non-singlet g_1 is discussed. Explicit expressions combining DGLAP with our results are presented.

  16. Generalization of the DGLAP for the structure function g_1 to the region of small x

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2005-01-01

    The explicit expressions for the non-singlet and singlet components of the DIS structure function g_1 comprising the DGLAP -expressions for the coefficient functions and the anomalous dimensions, and accounting for the total resummation of the most singular contributions to those are obtained.

  17. Helac-Nlo

    Science.gov (United States)

    Bevilacqua, G.; Czakon, M.; Garzelli, M. V.; van Hameren, A.; Kardos, A.; Papadopoulos, C. G.; Pittau, R.; Worek, M.

    2013-03-01

    Based on the OPP technique and the HELAC framework, HELAC-1LOOP is a program that is capable of numerically evaluating QCD virtual corrections to scattering amplitudes. A detailed presentation of the algorithm is given, along with instructions to run the code and benchmark results. The program is part of the HELAC-NLO framework that allows for a complete evaluation of QCD NLO corrections. Catalogue identifier: AEOC_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOC_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 290945 No. of bytes in distributed program, including test data, etc.: 3013326 Distribution format: tar.gz Programming language: Fortran (gfortran(http://gcc.gnu.org/fortran/), lahey95 (http://www.lahey.com), ifort3(http://software.intel.com)). Computer: Any. Operating system: Linux, Unix, Mac OS. Classification: 11.1. Nature of problem: The evaluation of virtual one-loop amplitudes for multi-particle scattering is a long-standing problem [1]. In recent years the OPP reduction technique [2] opened the road for a fully numerical approach based on the evaluation of the one-loop amplitude for well-defined values of the loop momentum. Solution method: By using HELAC [3-5] and CutTools [6], HELAC-1LOOP is capable of evaluating QCD virtual corrections [7]. The one-loop n-particle amplitudes are constructed as part of the n+2 tree-order ones, by using the basic recursive algorithm used in HELAC. A Les Houches Event (LHE) file is produced, combining the complete information from tree-order and virtual one-loop contributions. In conjunction with real corrections, obtained with the use of HELAC-DIPOLES [8], the full NLO corrections can be computed. The program has been successfully used in many applications.

  18. Exclusive meson production at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Diehl, M.; Kugler, W.

    2007-06-15

    We report on numerical studies of the NLO corrections to exclusive meson electroproduction, both in collider and fixed-target kinematics. Corrections are found to be huge at small x{sub B} and moderate at intermediate or large x{sub B}. (orig.)

  19. Phenomenology of jet physics in the BFKL formalism at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Schwennsen, F.

    2007-01-15

    We study jet physics in the high energy regime of QCD. Based on the NLO BFKL equation, we construct a vertex for the production of a jet at central rapidity in k{sub T}-factorization. A jet algorithm is introduced, and we take special care of the separation of multi-Regge and quasi-multi-Regge kinematics. The connection with the energy scale of the evolution is investigated in detail. The result is discussed for two situations: scattering of highly virtual photons, which requires a symmetric energy scale to separate the impact factors from the gluon Green's function, and hadron-hadron collisions, where a non-symmetric scale choice is needed. For the second case we are able to de ne a NLO unintegrated gluon density, valid in the small-x regime, and give the evolution equation for this density as well. In the second part, we examine the angular decorrelation of Mueller- Navelet jets. Using an operator formalism in the space of anomalous dimension and conformal spin, we implement the NLO BFKL Green's function to study the rapidity dependence of angular decorrelations. We incorporate the necessary summation of collinearly enhanced corrections beyond NLO accuracy. We compare our results with data from the Tevatron p anti p-collider and provide predictions for the LHC as well. We also extend our study to the angular decorrelation between a forward jets and the electron in deep inelastic ep scattering. The angular decorrelation has not been measured in DIS so far, but we give theoretical results for this observable which already implement the experimental cuts. (orig.)

  20. NLO Corrections to Hard Process in Parton Shower MC - KrkNLO Method

    CERN Document Server

    Jadach, S; Sapeta, S; Siódmok, A; Skrzypek, M

    2015-01-01

    A new method of combining an NLO-corrected hard process with an LO parton shower Monte Carlo, nicknamed {\\sf KrkNLO}, was proposed recently. It is simpler than well-established two other methods: {\\sf MC@NLO} and {\\sf POWHEG}. In this contribution, we present some results of extensive numerical tests of the new method for single $Z$-boson production at hadron colliders and numerical comparisons with two other methods as well as with NNLO calculations.

  1. First steps towards WHIZARD + NLO

    Energy Technology Data Exchange (ETDEWEB)

    Chokoufe, Bijan; Reuter, Juergen; Weiss, Christian [DESY Hamburg (Germany); Kilian, Wolfgang [Uni Siegen (Germany)

    2015-07-01

    WHIZARD is a multi-purpose event generator for hadron- and lepton-colliders, considering the standard model as well as a multitude of BSM models. The current version of the program is only capable of automatically performing leading-order calculations, contributions of higher virtual orders being available for some specific kinds of processes. However, many applications require at least next-to-leading order accuracy. We present a first extension of WHIZARD which can also deal with processes at next-to-leading order, using the Frixione-Kunszt-Signer subtraction scheme. The program structure is briefly explained, focussing on the various components of the calculation and the corresponding interface to one-loop programs like GoSam. Finally, first results for NLO massless QCD are presented.

  2. NLO production of W' bosons at hadron colliders using the MC@NLO and POWHEG methods

    CERN Document Server

    Papaefstathiou, Andreas

    2009-01-01

    We present a next-to-leading order (NLO) treatment of the production of a new charged heavy vector boson, generically called W', at hadron colliders via the Drell-Yan process. We fully consider the interference effects with the Standard Model W boson and allow for arbitrary chiral couplings to quarks and leptons. We present results at both leading order (LO) and NLO in QCD using the MC@NLO/Herwig++ and POWHEG methods. We derive observation curves on the mass-width plane for the LO case and give the significance for a sample of NLO mass-width points. The event generator used, Wpnlo, is fully customisable and publicly available.

  3. Evolution equations for higher moments of angular momentum distributions

    CERN Document Server

    Hägler, P

    1998-01-01

    Based on a sumrule for the nucleon spin we expand quark and gluon orbital angular momentum operators and derive an evolution matrix for higher moments of the corresponding distributions. In combination with the spin-dependent DGLAP-matrix we find a complete set of spin and orbital angular momentum evolution equations.

  4. Regge behaviour of distribution functions and and -evolutions of gluon distribution function at low-

    Indian Academy of Sciences (India)

    U Jamil; J K Sarma

    2007-08-01

    In this paper, and -evolutions of gluon distribution function from Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) evolution equation in leading order (LO) at low- are presented assuming the Regge behaviour of quarks and gluons at this limit. We compare our results of gluon distribution function with MRST 2001, MRST 2004 and GRV 1998 parametrizations and show the compatibility of Regge behaviour of quark and gluon distribution functions with perturbative quantum chromodynamics (PQCD) at low-. We also discuss the limitations of Taylor series expansion method used earlier to solve DGLAP evolution equations in the Regge behaviour of distribution functions.

  5. Organic NLO Polymers. 5. Homopolymerization of Indole Based NLO-phore: A Heterocycle Chi(2)NLO Main-Chain Polymer

    Science.gov (United States)

    1994-05-28

    Lackrltz" and Lee-Yin Liu 2J. 1 wje I Oi School of Chemical SA~giiaeuiat, Purdue Unioersity, Wesit NK InOR Laftbyet ,. A 479071Z26 cHOI, coa 9t Ti (Os3...o /co m. c~ Introduction The design and synthesis of nw NLO materials for i .. CbYt and bucyl optoacave device appli&ctons an be accomplished...through a 2 variety of schemne.’ Tin development of polymeric J" NLO 2Qj:Q1j’TJ materials has boen approached firom a variety od ceative Is on design

  6. Transport at ''NLO'' in hot QCD

    CERN Document Server

    CERN. Geneva

    2016-01-01

    The study of QCD kinetics is driven by a vast array of the experimental measurements of transport at the LHC, ranging from heavy quark energy loss, jet suppression, and hydrodynamics. I first review the fundamental elements of QCD kinetic theory, i.e. plasma screening, 2to2 scattering, and medium modified collinear bremsstrahlung. Then I will summarize recent progress in calculating these elements and their interplay at "NLO" -- "NLO" refers to an order $\\sqrt{\\alpha_s}$ correction to the plasma processes arising from the statistical fluctuations of soft gluons. These "NLO" calculations suggest a computational strategy where the influence of the Debye sector on the real time dynamics of the hard lightlike modes can be incorporated into a few medium coefficients (such as the drag coefficient and $\\hat{q}$), which can be simulated with a Euclidean 3D dimensionally reduced theory.

  7. NLO corrections to the Kernel of the BKP-equations

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, J. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Fadin, V.S. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation); Novosibirskij Gosudarstvennyj Univ., Novosibirsk (Russian Federation); Lipatov, L.N. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Vacca, G.P. [INFN, Sezione di Bologna (Italy)

    2012-10-02

    We present results for the NLO kernel of the BKP equations for composite states of three reggeized gluons in the Odderon channel, both in QCD and in N=4 SYM. The NLO kernel consists of the NLO BFKL kernel in the color octet representation and the connected 3{yields}3 kernel, computed in the tree approximation.

  8. Integration of fastNLO into MCPLOTS

    CERN Document Server

    Tyros, Stefanos

    1993-01-01

    RIVET is a very popular tool that allows precise comparisons between measurements and Monte Carlo (MC) event generators. The MCPLOTS project at CERN uses its functionality to provide a browsable repository of such comparison plots. Higher order predictions, however, are usually too time consuming to be included in these comparisons. fastNLO provides precalculated interpolation tables that can deliver histograms of differential cross sections quickly and efficiently. In this project the capabilities of fastNLO with RIVET were combined to enable the fast histogram production for inclusion into the MCPLOTS collection on request of visitors of the corresponding web page.

  9. Non-singlet spin structure function $g^{NS}_{1} (x,t)$ in the DGLAP approach

    Indian Academy of Sciences (India)

    Neelakshi N K Borah; D K Choudhury; P K Sahariah

    2012-10-01

    An analytical solution of the non-singlet polarized parton distribution $ q^{NS} (x, Q^{2}) = ( u(x, Q^{2}) − d(x, Q^{2}))$ is obtained by solving the DGLAP (Gribov and Lipatov, Sov. J. Nucl. Phys. 15, 438 (1972); Lipatov, ibid, 20, 94 (1975); Dokshitzer, Sov. Phys. JETP 46, 641 (1997); Altarelli and Parisi, Nucl. Phys. B126, 298 (1977)) equation by the method of characteristics. We then evaluate the non-singlet spin-dependent structure function $g^{NS}_{1}$ . The result is compared with the data from HERMES (Airapetian et al, Phys. Rev. D75, 012007 (2007)).

  10. Organometallic NLO Polymers. Accordian Main-Chain NLO Polymers of Ferrocene

    Science.gov (United States)

    1991-12-13

    suggest that the reaction conditions required to carry out the Lewis acid catalyzed transesterification polycondensation are having deleterious effects on...organometallic main-chain NLO polymers. Our research 1"n -U has continued to f--cus on ferrocene based NLO polymers . MFP because of the outstanding results...under rt-ad pressure. The crude product wargood functional group tolerance because of the mild base (i.e. dissolved in chloroform and precipitated in

  11. MC rate at NLO for heavy flavour photoproduction at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Toll, Tobias

    2010-02-15

    A Monte Carlo at next-to-leading order (MC rate at NLO) has been constructed for the production of heavy quark flavours in photoproduction. As such, it is the rst Monte Carlo event generator with next-to-leading order (NLO) accuracy for a process in lepton hadron scattering. In order to construct such an MC rate at NLO, the matrix element for the process has to be calculated at NLO and then be matched with a parton shower. When doing this, it is important that none of the parton configurations produced are doubly counted. In this thesis, the concept of a Monte Carlo event generator will be explained, with emphasis on the HERWIG parton shower. Also, different techniques of calculating matrix elements at NLO accuracy will be explained. It will then be shown how the NLO calculation can be matched with the HERWIG parton shower in an MC rate at NLO without double counting, producing unweighted events at NLO-accuracy. Many comparisons are made between the MC rate at NLO here constructed, the HERWIG Monte Carlo and the FMNR NLO calculation. Also many comparisons are made to HERA data from the H1 and ZEUS experiments. It is shown that all HERA data with heavy quarks produced in photoproduction can be described by the MC rate at NLO program constructed in this thesis. (orig.)

  12. NLO vector boson production with light jets

    CERN Document Server

    Bern, Z; Dixon, L J; Cordero, F Febres; Forde, D; Gleisberg, T; Hoeche, S; Ita, H; Kosower, D A; Maitre, D; Ozeren, K

    2012-01-01

    In this contribution we present recent progress in the computation of next-to-leading order (NLO) QCD corrections for the production of an electroweak vector boson in association with jets at hadron colliders. We focus on results obtained using the virtual matrix element library BLACKHAT in conjunction with SHERPA, focusing on results relevant to understanding the background to top production.

  13. Q2-evolution of parton densities at small x values

    CERN Document Server

    Kotikov, A V

    2016-01-01

    The Bessel-inspired behavior of parton densities at small x, obtained in the case of the flat initial conditions for DGLAP evolution equations, is used in the fixed flavor scheme to analyze precise H1+ZEUS combined data on the structure function F2.

  14. NLO in correlation of phase transition and the alkaline metal environment effect on it in KDP family

    Energy Technology Data Exchange (ETDEWEB)

    Ennaceur, Nasreddine, E-mail: nasr.ennaceur@yahoo.fr [Laboratoire Physico-chimie de l' État Solide, Faculté des Sciences, Université de Sfax, BP 1171, 3000 (Tunisia); Laboratoire de Photonique Quantique et Moléculaire Institut d’Alembert—École Normale Supérieure, 61 avenue du Président Wilson, 94230 Cachan (France); Ledoux-Rak, Isabelle; Singh, Anu [Laboratoire de Photonique Quantique et Moléculaire Institut d’Alembert—École Normale Supérieure, 61 avenue du Président Wilson, 94230 Cachan (France); Mhiri, Tahar; Jarraya, Khaled [Laboratoire Physico-chimie de l' État Solide, Faculté des Sciences, Université de Sfax, BP 1171, 3000 (Tunisia)

    2013-11-01

    The NaH{sub 2}(P{sub 0.48}As{sub 0.52})O{sub 4}·H{sub 2}O (NDAP) compounds allow favorable conditions to the study of evolution of the NLO response during the non-centrosymmetry phases transitions. In fact, NDAP shows the existence of three reversible non-centrosymmetry phase transitions between 272 and 313 K. These experiments are good tools for probing phase transitions and their nature. In this process, several experiments are useful to reveal not only an agreement between the thermal and the quadratic nonlinear (NLO) studies, but also an attempt amongst other things to correlate the probable effect of the alkaline environment of the KDP family on the effectiveness of the NLO intensity.

  15. Synthesis of Polymers Containing Covalently Bonded NLO Chromophores

    Science.gov (United States)

    Denga, Xiao-Hua; Sanghadasa, Mohan; Walton, Connie; Penn, Benjamin B.; Amai, Robert L. S.; Clark, Ronald D.

    1998-01-01

    Polymers containing covalently bonded nonlinear optical (NLO) chromophores are expected to possess special properties such as greater stability, better mechanical processing, and easier film formation than their non-polymeric equivalent. For the present work, polymethylmethacrylate (PMMA) was selected as the basic polymer unit on which to incorporate different NLO chromophores. The NLO components were variations of DIVA {[2-methoxyphenyl methylidene]-propanedinitrile} which we prepared from vanillin derivatives and malononitrile. These were esterified with methacrylic acid and polymerized either directly or with methyl methacrylate to form homopolymers or copolymers respectively. Characterization of the polymers and NLO property studies are underway.

  16. Low-x contribution to the Bjorken sum rule within unified $ln^2x+$LO DGLAP approximation

    CERN Document Server

    Kotlorz, D

    2004-01-01

    The small-$x$ contributions to the Bjorken sum rule within unified picture $ln^2x+$LO DGLAP for different input parametrisations $g_1^{NS}(x,Q_0^2)$ are presented. Theoretical predictions for $\\int_{0}^{0.003} g_1^{NS}(x,Q^2=10) dx$ are compared with the SMC small-$x$ data. Rough estimation of the slope $\\lambda$, controlling the small-$x$ behaviour of $g_1^{NS}\\sim x^{-\\lambda}$ from the obtained results and SMC data is performed. The crucial role of the running coupling $\\alpha_s=\\alpha_s(Q^2/z)$ at low-$x$ is taken into account.

  17. Electroweak Higgs plus three jet production at NLO QCD

    Energy Technology Data Exchange (ETDEWEB)

    Campanario, Francisco [Valencia-CSIC Univ. (Spain). IFIC; Figy, Terrance M. [Manchester Univ. (United Kingdom). School of Physics and Astronomy; Plaetzer, Simon [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Sjoedahl, Malin [Lund Univ. (Sweden). Dept. of Astronomy and Theoretical Physics

    2013-11-15

    We calculate next-to-leading order (NLO) QCD corrections to electroweak Higgs plus three jet production. Both vector boson fusion (VBF) and Higgs-strahlung type contributions are included along with all interferences. The calculation is implemented within the Matchbox NLO framework of the Herwig++ event generator.

  18. NLO QCD+EW for V+jets

    CERN Document Server

    Schönherr, Marek; Lindert, Jonas M; Pozzorini, Stefano; Maierhöfer, Philipp

    2016-01-01

    In this contribution recent results regarding the NLO electroweak corrections for vector boson production in association with jets are presented. Besides discussing the phenomenology of the fixed-order results, their corporation in existing NLO QCD parton shower matched and merged calculations, which can directly be used in experimental analyses, will be shown.

  19. NLO error propagation exercise data collection system

    Energy Technology Data Exchange (ETDEWEB)

    Keisch, B.; Bieber, A.M. Jr.

    1983-01-01

    A combined automated and manual system for data collection is described. The system is suitable for collecting, storing, and retrieving data related to nuclear material control at a bulk processing facility. The system, which was applied to the NLO operated Feed Materials Production Center, was successfully demonstrated for a selected portion of the facility. The instrumentation consisted of off-the-shelf commercial equipment and provided timeliness, convenience, and efficiency in providing information for generating a material balance and performing error propagation on a sound statistical basis.

  20. Ntuples for NLO Events at Hadron Colliders

    CERN Document Server

    Bern, Z.; Febres Cordero, F.; Höche, S.; Ita, H.; Kosower, D.A.; Maitre, D.

    2014-01-01

    We present an event-file format for the dissemination of next-to-leading-order (NLO) predictions for QCD processes at hadron colliders. The files contain all information required to compute generic jet-based infrared-safe observables at fixed order (without showering or hadronization), and to recompute observables with different factorization and renormalization scales. The files also make it possible to evaluate cross sections and distributions with different parton distribution functions. This in turn makes it possible to estimate uncertainties in NLO predictions of a wide variety of observables without recomputing the short-distance matrix elements. The event files allow a user to choose among a wide range of commonly-used jet algorithms and jet-size parameters. We provide event files for a $W$ or $Z$ boson accompanied by up to four jets, and for pure-jet events with up to four jets. The files are for the Large Hadron Collider with a center of mass energy of 7 or 8 TeV. A C++ library along with a Python in...

  1. NLO Jet Physics with BlackHat

    Energy Technology Data Exchange (ETDEWEB)

    Berger, C.F.; /MIT, LNS; Bern, Z.; /UCLA; Dixon, L.J.; /SLAC; Cordero, F.Febres; /Simon Bolivar U.; Forde, D.; /CERN /NIKHEF, Amsterdam; Gleisberg, T.; /SLAC; Ita, H.; /UCLA; Kosower, D.A.; /DAPNIA, Saclay; Maitre, D.; /Durham U.

    2010-02-15

    We present several results obtained using the BLACKHAT next-to-leading order QCD program library, in conjunction with SHERPA. In particular, we present distributions for vector boson plus 1,2,3-jet production at the Tevatron and at the asymptotic running energy of the Large Hadron Collider, including new Z + 3-jet distributions. The Z + 2-jet predictions for the second-jet P{sub T} distribution are compared to CDF data. We present the jet-emission probability at NLO in W + 2-jet events at the LHC, where the tagging jets are taken to be the ones furthest apart in pseudorapidity. We analyze further the large left-handed W{sup {+-}} polarization, identified in our previous study, for W bosons produced at high P{sub T} at the LHC.

  2. Is it possible to unify the QCD evolution of structure functions in X and $Q^{2}$?

    CERN Document Server

    Peschanski, R

    1995-01-01

    We start from the two existing QCD evolution equations for structure functions, the BFKL and DGLAP equations, and discuss the theoretical hints for a unifying picture of the evolution in x and Q^2. The main difficulty is due to the property of angular ordering of the gluon radiation driving the evolution and the cancellation of the related collinear singularities. At the leading \\log\\ 1/x and leading \\log \\ Q^2 accuracy, we find a unified set of equations satisfying the constraints.

  3. Triple collinear emissions in parton showers

    Energy Technology Data Exchange (ETDEWEB)

    Höche, Stefan [SLAC; Prestel, Stefan [Fermilab

    2017-05-01

    A framework to include triple collinear splitting functions into parton showers is presented, and the implementation of flavor-changing NLO splitting kernels is discussed as a first application. The correspondence between the Monte-Carlo integration and the analytic computation of NLO DGLAP evolution kernels is made explicit for both timelike and spacelike parton evolution. Numerical simulation results are obtained with two independent implementations of the new algorithm, using the two independent event generation frameworks Pythia and Sherpa.

  4. Q 2-evolution of parton densities at small x values. Charm contribution in the combined H1 and ZEUS F 2 data

    Science.gov (United States)

    Kotikov, A. V.; Shaikhatdenov, B. G.

    2017-09-01

    The Bessel-inspired behavior of parton densities at small x, obtained in the case of the flat initial conditions for DGLAP evolution equations, is used in the fixed flavor scheme to analyze precise H1 and ZEUS combined data on the structure function F 2.

  5. Numerical solution of $Q^2$ evolution equations for fragmentation functions

    CERN Document Server

    Hirai, M

    2011-01-01

    Semi-inclusive hadron-production processes are becoming important in high-energy hadron reactions. They are used for investigating properties of quark-hadron matters in heavy-ion collisions, for finding the origin of nucleon spin in polarized lepton-nucleon and nucleon-nucleon reactions, and possibly for finding exotic hadrons. In describing the hadron-production cross sections in high-energy reactions, fragmentation functions are essential quantities. A fragmentation function indicates the probability of producing a hadron from a parton. Its $Q^2$ dependence is described by the standard DGLAP (Dokshitzer-Gribov-Lipatov-Altarelli-Parisi) evolution equations, which are often used in theoretical and experimental analyses of the fragmentation functions and in calculating semi-inclusive cross sections. The DGLAP equations are complicated integro-differential equations, which cannot be solved in an analytical method. In this work, a simple method is employed for solving the evolution equations by using Gauss-Legen...

  6. Conformal kernel for NLO BFKL equation in ${\\cal N}$=4 SYM

    Energy Technology Data Exchange (ETDEWEB)

    Balitsky, Ian; Chirilli, Giovanni

    2009-01-01

    Using the requirement of M\\"{o}bius invariance of ${\\cal N}$=4 SYM amplitudes in the Regge limit we restore the conformal NLO BFKL kernel out of the eigenvalues known from the forward NLO BFKL result.

  7. NLO vertex for a forward jet plus a rapidity gap at high energies

    Science.gov (United States)

    Hentschinski, Martin; Madrigal Martínez, José Daniel; Murdaca, Beatrice; Vera, Agustín Sabio

    2015-04-01

    We present the calculation of the forward jet vertex associated to a rapidity gap (coupling of a hard pomeron to the jet) in the BFKL formalism at next-to-leading order (NLO). Real emission contributions are computed via Lipatov's effective action. The NLO jet vertex turns out to be finite within collinear factorization and allows, together with the NLO non-forward gluon Green's function, to perform NLO studies of jet production in diffractive events (e.g. Mueller-Tang dijets).

  8. NLO Vertex for a Forward Jet plus a Rapidity Gap at High Energies

    CERN Document Server

    Hentschinski, Martin; Murdaca, Beatrice; Vera, Agustín Sabio

    2015-01-01

    We present the calculation of the forward jet vertex associated to a rapidity gap (coupling of a hard pomeron to the jet) in the BFKL formalism at next-to-leading order (NLO). Real emission contributions are computed via Lipatov's effective action. The NLO jet vertex turns out to be finite within collinear factorization and allows, together with the NLO non-forward gluon Green's function, to perform NLO studies of jet production in diffractive events (e.g. Mueller-Tang dijets).

  9. Fully differential NLO predictions for the rare muon decay

    Science.gov (United States)

    Pruna, G. M.; Signer, A.; Ulrich, Y.

    2017-02-01

    Using the automation program GoSam, fully differential NLO corrections were obtained for the rare decay of the muon μ → eν ν bar ee. This process is an important Standard Model background to searches of the Mu3e Collaboration for lepton-flavor violation, as it becomes indistinguishable from the signal μ → 3 e if the neutrinos carry little energy. With our NLO program we are able to compute the branching ratio as well as custom-tailored observables for the experiment. With minor modifications, related decays of the tau can also be computed.

  10. NLO Inclusive Jet Production in kt-factorization

    CERN Document Server

    Bartels, J; Schwennsen, F

    2006-01-01

    In this contribution we discuss the inclusive production of jets in central regions of rapidity in the context of $k_T$-factorization at next-to-leading order (NLO). We work in the Regge limit of QCD and use the NLO BFKL results. A jet cone definition is proposed together with a phase-space separation into multi-Regge and quasi-multi-Regge kinematics. We discuss scattering of highly virtual photons, with a symmetric energy scale to separate the impact factors from the gluon Green's function, and hadron-hadron collisions, with a non-symmetric scale choice.

  11. Fully differential NLO predictions for the rare muon decay

    Directory of Open Access Journals (Sweden)

    G.M. Pruna

    2017-02-01

    Full Text Available Using the automation program GoSam, fully differential NLO corrections were obtained for the rare decay of the muon μ→eνν¯ee. This process is an important Standard Model background to searches of the Mu3e Collaboration for lepton-flavor violation, as it becomes indistinguishable from the signal μ→3e if the neutrinos carry little energy. With our NLO program we are able to compute the branching ratio as well as custom-tailored observables for the experiment. With minor modifications, related decays of the tau can also be computed.

  12. Electroweak supersymmetric dark matter annihilation in DM rate at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Schmiemann, Saskia; Klasen, Michael; Kovarik, Karol; Steppeler, Patrick [Institut fuer Theoretische Physik, Universitaet Muenster (Germany); Herrmann, Bjoern [LAPTh, Universite Savoie Mont Blanc, CNRS (France); Harz, Julia [CNRS, UMR 7589, LPTHE, Paris (France); Sorbonne Universites, Institut Lagrange de Paris (ILP) (France); Sorbonne Universites, UPMC Univ Paris 06, UMR 7589, LPTHE (France)

    2016-07-01

    Today there are several pieces of evidence for dark matter. One well-known experiment is the measurement of the Dark Matter relic density by the Planck satellite. The talk introduces the 'Dark Matter at next-to-leading order' (DM rate at NLO) project which provides predictions for the dark matter relic density in the MSSM including higher-order corrections. After an introduction of the project DM rate at NLO, I shortly speak about the calculation of the electroweak processes. The main focus lies on the effects of the electroweak tree-level processes on the relic density of neutralinos within selected scenarios.

  13. Light-cone sum rules for the nucleon form factors in NLO; Lichtkegelsummenregeln fuer die Formfaktoren des Nukleons in NLO

    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.)

  14. Climbing NLO and NNLO Summits of Weak Decays

    CERN Document Server

    Buras, Andrzej J

    2011-01-01

    I describe the history of the calculations of NLO and NNLO QCD corrections to weak decays of mesons and particle-antiparticle mixing in the period 1988-2010. Also existing calculations of electroweak and QED corrections to these processes are included in this presentation. These efforts bear some analogies to the climbing of Himalayas and various expeditions by several teams of strongly motivated "climbers", acting mainly in Germany, Italy, Poland and Switzerland, allowed to move this field from the LO through the NLO to the NNLO level. The material is meant to be a guide to the rich literature on NLO and NNLO corrections in question and includes several anecdots related to the climbs that I was involved in. While, by no means this presentation should be regarded as a review of the size of NLO and NNLO corrections to weak decays, I hope that some of the comments made in the course of the presentation could turn out to be not only amusing but also instructive.

  15. Four-body contributions to B -> Xs gamma at NLO

    CERN Document Server

    Huber, Tobias; Virto, Javier

    2014-01-01

    Ongoing efforts to reduce the perturbative uncertainty in the B -> Xs gamma decay rate have resulted in a theory estimate to NNLO in QCD. However, a few contributions from multi-parton final states which are formally NLO are still unknown. These are parametrically small and included in the estimated error from higher order corrections, but must be computed if one is to claim complete knowledge of the B -> Xs gamma rate to NLO. A major part of these unknown pieces are four-body contributions corresponding to the partonic process b -> s qbar q gamma. We compute these NLO four-body contributions to B -> Xs gamma, and confirm the corresponding tree-level leading-order results. While the NLO contributions arise from tree-level and one-loop Feynman diagrams, the four-body phase-space integrations make the computation non-trivial. The decay rate contains collinear logarithms arising from the mass regularization of collinear divergences. We perform an exhaustive numerical analysis, and find that these contributions a...

  16. Impact Factor for Exclusive Diffractive Dijet Production with NLO Accuracy

    CERN Document Server

    Boussarie, R; Szymanowski, L; Wallon, S

    2016-01-01

    Relying on the shockwave approach, we present the main steps of the computation of the impact factor for the exclusive diffractive photo- or electro- production of a forward dijet with NLO accuracy. We provide details of the cancellation mechanisms for all the divergences which appear in the intermediate results.

  17. Nuclear PDFs at NLO - status report and review of the EPS09 results

    Energy Technology Data Exchange (ETDEWEB)

    Eskola, K.J. [Department of Physics, P.O. Box 35, FI-40014 University of Jyvaeskylae (Finland); Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Paukkunen, H.; Salgado, C.A. [Departamento de Fisica de Particulas and IGFAE, Universidade de Santiago de Compostela (Spain)

    2011-04-01

    We review the current status of the global DGLAP analysis of nuclear parton distribution functions, nPDFs, focusing on the recent EPS09 analysis [K.J. Eskola, H. Paukkunen, C.A. Salgado, JHEP 0904 (2009) 065. [ (arXiv:0902.4154 [hep-ph])

  18. Nuclear PDFs at NLO - status report and review of the EPS09 results

    Science.gov (United States)

    Eskola, K. J.; Paukkunen, H.; Salgado, C. A.

    2011-04-01

    We review the current status of the global DGLAP analysis of nuclear parton distribution functions, nPDFs, focusing on the recent EPS09 analysis [K.J. Eskola, H. Paukkunen, C.A. Salgado, JHEP 0904 (2009) 065. [ arXiv:0902.4154 [hep-ph

  19. NLO cross sections in 4 dimensions without DREG

    CERN Document Server

    Hernández-Pinto, R J; Rodrigo, G; Sborlini, G F R

    2016-01-01

    In this review, we present a new method for computing physical cross sections at NLO accuracy in QCD without using the standard Dimensional Regularisation. The algorithm is based on the Loop-Tree Duality theorem, which allow us to obtain loop integrals as a sum of phase-space integrals; in this way, transforming loop integrals into phase-space integrals, we propose a method to merge virtual and real contributions in order to find observables at NLO in $d=4$ space-time dimensions. In addition, the strategy described is used for computing the $\\gamma^*\\to q\\bar{q}(g)$ process. A more detailed discussion related on this topic can be found in Ref [1].

  20. Growth and Characterization of Organic NLO Crystal: β-Naphthol

    Institute of Scientific and Technical Information of China (English)

    S.Janarthanan; R.Sugaraj Samuel; S.Selvakumar; Y.C.Rajan; D.Jayaraman; S.Pandi

    2011-01-01

    Single crystals ofβ-Naphthol (βN), an organic nonlinear optical (NLO) material was successfully grown by temperature lowering method using chloroform as solvent. The initial compound was purified by repeated recrystallization process. As-grown crystals were characterized by single crystal X-ray diffraction (XRD) studies to ascertain that βN crystal crystallized in the monoclinic system with a noncemtrosymmetric space group. Vibrational frequencies of various functional groups in the crystals were derived from Fourier transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (NMR) spectrum. Optical characterization was done using UV-Visible near-infrared (NIR) spectroscopy. The thermal behaviour of the material was studied by thermo gravimetric and differential thermal plots. Scanning electron microscopy (SEM) study was carried out on the surface of the grown crystals to investigate the nature of defects in the crystal surface and the NLO property of the crystal was tested by Nd:YAG laser as a source.

  1. NLO electroweak corrections in extended Higgs sectors with RECOLA2

    Science.gov (United States)

    Denner, Ansgar; Lang, Jean-Nicolas; Uccirati, Sandro

    2017-07-01

    We present the computer code RECOLA2 along with the first NLO electroweak corrections to Higgs production in vector-boson fusion and updated results for Higgs strahlung in the Two-Higgs-Doublet Model and Higgs-Singlet extension of the Standard Model. A fully automated procedure for the generation of tree-level and one-loop matrix elements in general models, including renormalization, is presented. We discuss the application of the Background-Field Method to the extended models. Numerical results for NLO electroweak cross sections are presented for different renormalization schemes in the Two-Higgs-Doublet Model and the Higgs-Singlet extension of the Standard Model. Finally, we present distributions for the production of a heavy Higgs boson.

  2. Relic density computations at NLO: infrared finiteness and thermal correction

    CERN Document Server

    Beneke, Martin; Hryczuk, Andrzej

    2014-01-01

    There is an increasing interest in accurate dark matter relic density predictions, which requires next-to-leading order (NLO) calculations. The method applied up to now uses zero-temperature NLO calculations of annihilation cross sections in the standard Boltzmann equation for freeze-out, and is conceptually problematic, since it ignores the finite-temperature infrared (IR) divergences from soft and collinear radiation and virtual effects. We address this problem systematically by starting from non-equilibrium quantum field theory, and demonstrate on a realistic model that soft and collinear temperature-dependent divergences cancel in the collision term. Our analysis provides justification for the use of the freeze-out equation in its conventional form and determines the leading finite-temperature correction to the annihilation cross section. This turns out to have a remarkably simple structure.

  3. NLO predictions for SMEFT in the top-quark sector

    CERN Document Server

    Zhang, Cen

    2016-01-01

    Predictions for the Standard Model Effective Field Theory at the next-to-leading order accuracy in QCD, including parton-shower effects, have started to become available in the MadGraph5_aMC@NLO framework. In this talk we summarize some recent results for $t\\bar t$, single top, $t\\bar tZ/\\gamma$, and $t\\bar tH$ production channels at dimension six.

  4. Subtractive Renormalization Group Invariance: Pionless EFT at NLO

    Science.gov (United States)

    Timóteo, Varese S.; Szpigel, Sérgio; Durães, Francisco O.

    2010-11-01

    We show some results concerning the renormalization group (RG) invariance of the nucleon-nucleon (NN) interaction in pionless effective field theory at next-to-leading order (NLO), using a non-relativistic Callan-Symanzik equation (NRCS) for the driving term of the Lippmann-Schwinger (LS) equation with three recursive subtractions. The phase-shifts obtained for the RG evolved potential are same as those for the original potential, apart from relative differences of order 10-15.

  5. A critical appraisal of NLO+PS matching methods

    Science.gov (United States)

    Höche, Stefan; Krauss, Frank; Schönherr, Marek; Siegert, Frank

    2012-09-01

    In this publication, uncertainties in and differences between the M C@NLO and P OWHEG methods for matching next-to-leading order QCD calculations with parton showers are discussed. Implementations of both algorithms within the event generator S HERPA and based on Catani-Seymour subtraction are employed to assess the impact on a representative selection of observables. In the case of M C@NLO a substantial simplification is achieved by using dipole subtraction terms to generate the first emission. A phase space restriction is employed, which allows to vary in a transparent way the amount of non-singular radiative corrections that are exponentiated. Effects on various observables are investigated, using the production of a Higgs boson in gluon fusion, with or without an associated jet, as a benchmark process. The case of H+jet production is presented for the first time in an NLO+PS matched simulation. Uncertainties due to scale choices and non-perturbative effects are explored in the production of W ± and Z bosons in association with a jet. Corresponding results are compared to data from the Tevatron and LHC experiments.

  6. A critical appraisal of NLO+PS matching methods

    CERN Document Server

    Hoeche, Stefan; Schonherr, Marek; Siegert, Frank

    2011-01-01

    In this publication, uncertainties in and differences between the MC@NLO and POWHEG methods for matching next-to-leading order QCD calculations with parton showers are discussed. Implementations of both algorithms within the event generator Sherpa are employed to assess the impact on a representative selection of observables. In the MC@NLO approach a phase space restriction has been added to subtraction and parton shower, which allows to vary in a transparent way the amount of non-singular radiative corrections that are exponentiated. Effects on various observables are investigated, using the production of a Higgs boson in gluon fusion, with or without an associated jet, as a benchmark process. The case of H+jet production is presented for the first time in an NLO+PS matched simulation. Uncertainties due to scale choices and non-perturbative effects are explored in the production of W and Z bosons in association with a jet. Corresponding results are compared to data from the Tevatron and LHC experiments.

  7. NLO QCD Corrections to Electroweak Higgs Boson Production in Association with Three Jets at the LHC

    Science.gov (United States)

    Figy, Terrance

    2017-01-01

    In this talk I will discuss the implementation of the next-to-leading order (NLO) perturbative QCD corrections to electroweak Higgs boson plus three jet production at the CERN Large Hadron Collider experiment within the Matchbox framework of the Herwig 7 event generator. Numerical results for integrated cross sections and kinematic distributions will be presented for a fixed-order NLO calculation and for a NLO calculation matched to a parton shower.

  8. QCD NLO and EW NLO corrections to tt¯H production with top quark decays at hadron collider

    Directory of Open Access Journals (Sweden)

    Zhang Yu

    2014-11-01

    Full Text Available Higgs boson production associated with a top quark pair is an important process in studying the nature of the newly discovered Higgs boson at the LHC. In this letter, we report on our calculations including the next-to-leading order (NLO QCD and NLO electroweak corrections to the pp→tt¯H process in the standard model. We present the integrated cross sections at the 14 TeV LHC and even at the future proton–proton colliders with s=33 and 100TeV. Our calculation includes the top quark subsequent decays by adopting the narrow width approximation. The kinematic distributions of Higgs boson and top quark decay products at the LHC are provided. We find that the O(αs2αew2 corrections are quantitatively comparable with the O(αs3αew corrections in some kinematic region.

  9. New simpler method of matching NLO corrections with parton shower Monte Carlo

    CERN Document Server

    Jadach, S; Sapeta, S; Siodmok, A; Skrzypek, M

    2016-01-01

    Next steps in development of the KrkNLO method of implementing NLO QCD corrections to hard processes in parton shower Monte Carlo programs are presented. This new method is a simpler alternative to other well-known approaches, such as MC@NLO and POWHEG. The KrkNLO method owns its simplicity to the use of parton distribution functions (PDFs) in a new, so-called Monte Carlo (MC), factorization scheme which was recently fully defined for the first time. Preliminary numerical results for the Higgs-boson production process are also presented.

  10. Parametrization of the QCD coupling in the evolution equations

    Energy Technology Data Exchange (ETDEWEB)

    Ermolaev, B.I. [H. Niewodniczanski Nuclear Physics Institute PAN, 31-342 Krakow (Poland); Ioffe Physico-Technical Institute, 194021 St. Petersburg (Russian Federation)], E-mail: boris.ermolaev@cern.ch; Troyan, S.I. [St. Petersburg Institute of Nuclear Physics, 188300 Gatchina (Russian Federation)

    2008-08-21

    We examine the parametrization of the QCD coupling in the evolution equations, including DGLAP. Our conclusion is that the well-known parametrization, where the argument of the coupling is k{sub perpendicular}{sup 2}/{beta} or just k{sub perpendicular}{sup 2}, stands only if the lowest integration limit in the transverse momentum space (the starting point {mu}{sup 2} of the Q{sup 2}-evolution) obeys the relation {mu}>>{lambda}{sub QCD}exp({pi}/2), otherwise the coupling should be replaced by the more complicated expression presented in Eq. (29)

  11. Parametrization of the QCD coupling in the Evolution Equations

    CERN Document Server

    Ermolaev, B I

    2008-01-01

    We examine the parametrization of the QCD coupling in the Evolution Equations, including DGLAP. Our conclusion is that the well-known parametrization, where the argument of the coupling is k^2_{\\perp}/\\beta or just k^2_{\\perp}, stands only if the lowest integration limit in the transverse momentum space (the starting point mu^2 of the Q^2 -evolution) obeys the relation mu >> Lambda_{QCD} \\exp {(\\pi/2)}, otherwise the coupling should be replaced by the more complicated expression presented in Eq. (37).

  12. Hard gluon evolution of nucleon generalized parton distributions in the light-front quark model. Hard gluon evolution of nucleon GPDs

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Neetika [Indian Institute of Science Education and Research Mohali, Mohali (India)

    2016-04-15

    We incorporate the perturbative evolution effects in the generalized parton distributions (GPDs) calculated in effective light-front quark model for the nucleon. The perturbative effects enter into formalism through the evolution of GPDs according to the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi-like (DGLAP) equation. We obtain the evolved GPDs in the momentum space and transverse impact parameter space. We observe that combining the light-front quark model with the perturbative evolution effects, give the effective model for studying the phenomenological GPDs. (orig.)

  13. The SM and NLO Multileg Working Group: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, J.R.; Archibald, J.; Badger, S.; Ball, R.D.; Bevilacqua, G.; Bierenbaum, I.; Binoth, T.; Boudjema, F.; Boughezal, R.; Bredenstein, A.; Britto, R.; Campanelli, M.; Campbell, J.; Carminati, L.; Chachamis, G.; Ciulli, V.; Cullen, G.; Czakon, M.; Del Debbio, L.; Denner, A.; Dissertori, G.; /Edinburgh U. /Zurich, ETH /Michigan State U. /CAFPE, Granada /CERN /Durham U., IPPP /DESY, Zeuthen /Democritos Nucl. Res. Ctr. /Valencia U., IFIC /Annecy, LAPTH /Zurich U. /KEK, Tsukuba /Saclay, SPhT /University Coll. London /Fermilab /INFN, Milan /Milan U. /PSI, Villigen /Florence U. /INFN, Florence /RWTH Aachen U.

    2012-04-10

    After years of waiting, and after six Les Houches workshops, the era of LHC running is finally upon us, albeit at a lower initial center-of-mass energy than originally planned. Thus, there has been a great sense of anticipation from both the experimental and theoretical communities. The last two years, in particular, have seen great productivity in the area of multi-parton calculations at leading order (LO), next-to-leading order (NLO) and next-to-next-to-leading order (NNLO), and this productivity is reflected in the proceedings of the NLM group. Both religions, Feynmanians and Unitarians, as well as agnostic experimenters, were well-represented in both the discussions at Les Houches, and in the contributions to the write-up. Next-to-leading order (NLO) is the first order at which the normalization, and in some cases the shape, of perturbative cross sections can be considered reliable. This can be especially true when probing extreme kinematic regions, as for example with boosted Higgs searches considered in several of the contributions to this writeup. A full understanding for both standard model and beyond the standard model physics at the LHC requires the development of fast, reliable programs for the calculation of multi-parton final states at NLO. There have been many advances in the development of NLO techniques, standardization and automation for such processes and this is reflected in the contributions to the first section of this writeup. Many calculations have previously been performed with the aid of semi-numerical techniques. Such techniques, although retaining the desired accuracy, lead to codes which are slow to run. Advances in the calculation of compact analytic expressions for Higgs + 2 jets have resulted in the development of much faster codes, which extend the phenomenology that can be conducted, as well as making the code available to the public for the first time. A prioritized list of NLO cross sections was assembled at Les Houches in 2005

  14. Global analysis of nuclear parton distribution functions at leading and next-to-leading order perturbative QCD

    CERN Document Server

    Paukkunen, Hannu

    2009-06-01

    This is the introductory part of my PhD thesis which consists of two parts, the separate introduction and four published articles. The introduction begins by a technically detailed description of the DGLAP evolution and the fast numerical solving method for the DGLAP equations, which has been used in the numerical works of the published articles of this thesis. A write-up of the next-to-leading order (NLO) calculations for the deeply inelastic scattering (DIS) and the Drell-Yan (DY) dilepton production cross-sections is also included. The formalism of the inclusive single hadron production at NLO is described as well, although less rigorously. The introductory part ends with a discussion of the global QCD analyses in general, with a special attention paid to the major work of this thesis, the NLO analysis of nuclear parton densities and their uncertainties.

  15. NLO QCD corrections to electroweak Higgs boson plus three jet production at the LHC

    Energy Technology Data Exchange (ETDEWEB)

    Campanario, Francisco [Valencia-CSIC Univ. (Spain). IFIC; Figy, Terrance M. [Manchester Univ. (United Kingdom). School of Physics and Astronomy; Plaetzer, Simon [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Sjoedahl, Malin [Lund Univ. (Sweden). Dept. of Astronomy and Theoretical Physics

    2013-11-15

    The implementation of the full next-to-leading order (NLO) QCD corrections to electroweak Higgs boson plus three jet production at hadron colliders such as the LHC within the Matchbox NLO framework of the Herwig++ event generator is discussed. We present numerical results for integrated cross sections and kinematic distributions.

  16. Charged Higgs boson production in association with a top quark in MC@NLO

    NARCIS (Netherlands)

    Weydert, C.; Frixione, S.; Herquet, M.; Klasen, M.; Laenen, E.L.M.P.; Plehn, T.; Stavenga, G.; White, C.D.

    2010-01-01

    We discuss the calculation of charged Higgs boson production in association with top quark in the MC@NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model independent manner for wide applicability, and can be used if the charged Higgs boson mass is e

  17. Charged Higgs boson production in association with a top quark in MC@NLO

    NARCIS (Netherlands)

    Weydert, C.; Frixione, S.; Herquet, M.; Klasen, M.; Laenen, E.; Plehn, T.; Stavenga, G.; White, C.D.

    2010-01-01

    We discuss the calculation of charged Higgs boson production in association with a top quark in the MC@NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model-independent manner for wide applicability, and can be used if the charged Higgs boson mass is

  18. The nonsinglet structure function evolution by Laplace method

    Energy Technology Data Exchange (ETDEWEB)

    Boroun, G. R., E-mail: grboroun@gmail.com, E-mail: boroun@razi.ac.ir; Zarrin, S. [Razi University, Physics Department (Iran, Islamic Republic of)

    2015-12-15

    We derive a general scheme for the evolution of the nonsinglet structure function at the leadingorder (LO) and next-to-leading-order (NLO) by using the Laplace-transform technique. Results for the nonsinglet structure function are compared with MSTW2008, GRV, and CKMT parameterizations and also EMC experimental data in the LO and NLO analysis. The results are in good agreement with the experimental data and other parameterizations in the low- and large-x regions.

  19. Temporal mesonic correlators at NLO for any quark mass

    CERN Document Server

    Burnier, Y

    2013-01-01

    We present NLO results for thermal imaginary-time correlators in the vector and scalar channels as a function of the quark mass. The range of quark masses for which a non-relativistic approximation works in the temperature range considered is estimated, and charm quarks turn out to be a borderline case. Comparing with simulation data from fine lattices, we find good agreement in the vector channel but a substantial discrepancy in the scalar one. An explanation for the discrepancy is suggested in terms of physics of the quark-antiquark threshold region. Perturbative predictions for the bottom scalar spectral function around the threshold are also briefly reviewed.

  20. Anomalous couplings in WZ production beyond NLO QCD

    Energy Technology Data Exchange (ETDEWEB)

    Campanario, Francisco; Roth, Robin; Zeppenfeld, Dieter [Institute for Theoretical Physics, KIT, Karlsruhe (Germany); Sapeta, Sebastian [CERN PH-TH, Geneva (Switzerland)

    2016-07-01

    We study WZ production with anomalous couplings (AC) at anti nNLO QCD using the LoopSim method in combination with the Monte Carlo program VBFNLO. Higher order corrections to WZ production are dominated by additional hard jet radiation. Those contributions are insensitive to AC and should thus be suppressed in analyses. We do this using a dynamical jet veto based on the transverse energy of the QCD and EW final state particles. This removes jet dominated events without introducing problematic logs like a fixed p{sub T} jet veto.

  1. The SM and NLO Multileg Working Group: Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, J.R.; Archibald, J.; Badger, S.; Ball, R.D.; Bevilacqua, G.; Bierenbaum, I.; Binoth, T.; Boudjema, F.; Boughezal, R.; Bredenstein, A.; Britto, R.; Campanelli, M.; Campbell, J.; Carminati, L.; Chachamis, G.; Ciulli, V.; Cullen, G.; Czakon, M.; Del Debbio, L.; Denner, A.; Dissertori, G.; /Edinburgh U. /Zurich, ETH /Michigan State U. /CAFPE, Granada /CERN /Durham U., IPPP /DESY, Zeuthen /Democritos Nucl. Res. Ctr. /Valencia U., IFIC /Annecy, LAPTH /Zurich U. /KEK, Tsukuba /Saclay, SPhT /University Coll. London /Fermilab /INFN, Milan /Milan U. /PSI, Villigen /Florence U. /INFN, Florence /RWTH Aachen U.

    2012-04-10

    After years of waiting, and after six Les Houches workshops, the era of LHC running is finally upon us, albeit at a lower initial center-of-mass energy than originally planned. Thus, there has been a great sense of anticipation from both the experimental and theoretical communities. The last two years, in particular, have seen great productivity in the area of multi-parton calculations at leading order (LO), next-to-leading order (NLO) and next-to-next-to-leading order (NNLO), and this productivity is reflected in the proceedings of the NLM group. Both religions, Feynmanians and Unitarians, as well as agnostic experimenters, were well-represented in both the discussions at Les Houches, and in the contributions to the write-up. Next-to-leading order (NLO) is the first order at which the normalization, and in some cases the shape, of perturbative cross sections can be considered reliable. This can be especially true when probing extreme kinematic regions, as for example with boosted Higgs searches considered in several of the contributions to this writeup. A full understanding for both standard model and beyond the standard model physics at the LHC requires the development of fast, reliable programs for the calculation of multi-parton final states at NLO. There have been many advances in the development of NLO techniques, standardization and automation for such processes and this is reflected in the contributions to the first section of this writeup. Many calculations have previously been performed with the aid of semi-numerical techniques. Such techniques, although retaining the desired accuracy, lead to codes which are slow to run. Advances in the calculation of compact analytic expressions for Higgs + 2 jets have resulted in the development of much faster codes, which extend the phenomenology that can be conducted, as well as making the code available to the public for the first time. A prioritized list of NLO cross sections was assembled at Les Houches in 2005

  2. Automated NNLL + NLO resummation for jet-veto cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Becher, Thomas; Rothen, Lorena [Universitaet Bern, Albert Einstein Center for Fundamental Physics, Institut fuer Theoretische Physik, Bern (Switzerland); Frederix, Rikkert [CERN, TH Unit, PH Department, Geneva 23 (Switzerland); Neubert, Matthias [Johannes Gutenberg University, PRISMA Cluster of Excellence and Mainz Institut for Theoretical Physics, Mainz (Germany); LEPP, Cornell University, Department of Physics, Ithaca, NY (United States)

    2015-04-01

    In electroweak-boson production processes with a jet veto, higher-order corrections are enhanced by logarithms of the veto scale over the invariant mass of the boson system. In this paper, we resum these Sudakov logarithms at next-to-next-to-leading logarithmic accuracy and match our predictions to next-to-leading-order (NLO) fixed-order results. We perform the calculation in an automated way, for arbitrary electroweak final states and in the presence of kinematic cuts on the leptons produced in the decays of the electroweak bosons. The resummation is based on a factorization theorem for the cross sections into hard functions, which encode the virtual corrections to the boson production process, and beam functions, which describe the low-p{sub T} emissions collinear to the beams. The one-loop hard functions for arbitrary processes are calculated using the MadGraph5{sub a}MC rate at NLO framework, while the beam functions are process independent. We perform the resummation for a variety of processes, in particular for W{sup +}W{sup -} pair production followed by leptonic decays of the W bosons. (orig.)

  3. Penguin-dominated B -> PV decays in NLO perturbative QCD

    CERN Document Server

    Li, H; Li, Hsiang-nan; Mishima, Satoshi

    2006-01-01

    We study the penguin-dominated B -> PV decays, with P (V) representing a pseudo-scalar (vector) meson, in the next-to-leading-order (NLO) perturbative QCD (PQCD) formalism, concentrating on the B -> K phi, pi K^*, rho K, and omega K modes. It is found that the NLO corrections dramatically enhance the B -> rho K, \\omega K branching ratios, which were estimated to be small under the naive factorization assumption. The patterns of the direct CP asymmetries A_{CP}(B^0 -> rho^\\mp K^\\pm) \\approx A_{CP}(B^\\pm -> rho^0 K^\\pm) and |A_{CP}(B^0 -> pi^\\mp K^{*\\pm})| > |A_{CP}(B^\\pm -> pi^0 K^{*\\pm})| are predicted, differing from |A_{CP}(B^0 -> pi^\\mp K^\\pm)| >> |A_{CP}(B^\\pm -> pi^0 K^\\pm)|. The above patterns, if confirmed by data, will support the source of strong phases from the scalar penguin annihilation in PQCD. The results for the mixing-induced CP asymmetries S_f are consistent with those obtained in the literature, except that our S_{rho^0 K_S} is as low as 0.5.

  4. NLO QCD + EW corrections to $ZZZ$ production with subsequent leptonic decays at LHC

    CERN Document Server

    Hong, Wang; Wen-Gan, Ma; Lei, Guo; Xiao-Zhou, Li; Shao-Ming, Wang

    2016-01-01

    In this paper we present the NLO QCD + NLO EW corrections to the $ZZZ$ production with subsequent $Z$-boson leptonic decays at the LHC by adopting the improved narrow width approximation, which takes into account off-shell contributions and spin correlations. Integrated cross sections at $13$, $14$, $33$ and $100~{\\rm TeV}$ hadron colliders and various kinematic distributions are presented. Our numerical results show that the jet emission correction accounts for a large part of the total QCD correction, especially in the high energy region. By applying a proper cut to the jet transverse momentum, e.g., $p_{{\\rm \\,T,jet}} > p_{{\\rm \\,T,jet}}^{{\\rm \\,\\,\\,cut}}=50~{\\rm GeV}$, the jet emission correction can be reduced and the cross section is less dependent on the factorization/renormalization scale. This work reveals that both the NLO QCD and the NLO EW corrections are significant. For example, the NLO QCD, NLO EW and NLO QCD + EW relative corrections in the inclusive event selection scheme at the $13~{\\rm TeV}...

  5. Charged Higgs boson production in association with a top quark in MC@NLO

    Science.gov (United States)

    Weydert, C.; Frixione, S.; Herquet, M.; Klasen, M.; Laenen, E.; Plehn, T.; Stavenga, G.; White, C. D.

    2010-06-01

    We discuss the calculation of charged Higgs boson production in association with a top quark in the MC@NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model-independent manner for wide applicability, and can be used if the charged Higgs boson mass is either greater or less than the mass of the top quark. For the latter mass region, care is needed in defining the charged Higgs production mode due to interference with top pair production. We give a suitable definition applicable in an NLO (plus parton shower) context, and we present example results for the LHC.

  6. Charged Higgs boson production in association with a top quark in MC@NLO

    CERN Document Server

    Weydert, C; Herquet, M; Klasen, M; Laenen, E; Plehn, T; Stavenga, G; White, C D

    2010-01-01

    We discuss the calculation of charged Higgs boson production in association with top quark in the MC@NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model independent manner for wide applicability, and can be used if the charged Higgs boson mass is either greater or less than the mass of the top quark. For the latter mass region, care is needed in defining the charged Higgs production mode due to interference with top pair production. We give a suitable definition applicable in an NLO (plus parton shower) context, and present example results for the LHC.

  7. Study of HERA ep data at low Q{sup 2} and low x{sub Bj} and the need for higher-twist corrections to standard pQCD evolution

    Energy Technology Data Exchange (ETDEWEB)

    Abt, I. [Max-Planck-Institut fuer Physik, Muenchen (Germany). Werner-Heisenberg-Institut; Cooper-Sarkar, A.M. [Oxford Univ. (United Kingdom). Dept. of Physics; Foster, B. [Oxford Univ. (United Kingdom). Dept. of Physics; Hamburg Univ. (Germany). Inst. fuer Experimentelle Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Myronenko, V.; Wichmann, K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Wing, M. [University College London (United Kingdom)

    2016-04-15

    A detailed comparison of HERA data at low Bjorken-x and low four-momentum-transfer squared, Q{sup 2}, with predictions based on ln Q{sup 2} evolution (DGLAP) in perturbative Quantum Chromo Dynamics suggests inadequacies of this framework. The standard DGLAP evolution was augmented by including an additional higher-twist term in the description of the longitudinal structure function, F{sub L}. This additional term, F{sub L} A{sup HT}{sub L}/Q{sup 2}, improves the description of the reduced cross sections significantly. The resulting predictions for F{sub L} suggest that further corrections are required for Q{sup 2} less than about 2 GeV{sup 2}.

  8. NLO Electroweak Corrections to Higgs Boson Production at Hadron Colliders

    CERN Document Server

    Actis, S; Sturm, C; Uccirati, S

    2008-01-01

    Results for the complete NLO electroweak corrections to Standard Model Higgs production via gluon fusion are included in the total cross section for hadronic collisions. Artificially large threshold effects are avoided working in the complex-mass scheme. The numerical impact at LHC (Tevatron) energies is explored for Higgs mass values up to 500 GeV (200 GeV). Assuming a complete factorization of the electroweak corrections, one finds a +5 % shift with respect to the NNLO QCD cross section for a Higgs mass of 120 GeV both at the LHC and the Tevatron. Adopting two different factorization schemes for the electroweak effects, an estimate of the corresponding total theoretical uncertainty is computed.

  9. "H"-shape second order NLO polymers: synthesis and characterization.

    Science.gov (United States)

    Li, Zhong'an; Hu, Pan; Yu, Gui; Zhang, Wei; Jiang, Zuoquan; Liu, Yunqi; Ye, Cheng; Qin, Jingui; Li, Zhen

    2009-02-28

    In this work, two "H"-shape and one "AB"-type second order nonlinear optical (NLO) polymers were prepared for the first time. The linkage positions of chromophores in the "H"-shape polymers were shoulder-to-shoulder, in which the chromophore moieties were part of the polymeric backbone. The subtle structure could be easily modified by the introduction of different isolation groups, to adjust the property of the resultant polymers. All the polymers exhibited good film-forming ability and thermal stability. The second harmonic generation (SHG) experiments demonstrated that the two "H"-shape polymers (P1 and P2) exhibited large SHG coefficients of d(33) values (up to 90 pm V(-1)), and P2 even demonstrated relatively good long-term temporal stability.

  10. Automation of NLO processes and decays and POWHEG matching in WHIZARD

    Energy Technology Data Exchange (ETDEWEB)

    Reuter, Juergen; Chokoufe, Bijan [DESY, Hamburg (Germany). Theory Group; Hoang, Andre [Vienna Univ. (Austria). Faculty of Physics; Vienna Univ. (Austria). Erwin Schroedinger International Inst. for Mathematical Physics; Kilian, Wolfgang [Siegen Univ. (Germany); Stahlhofen, Maximilian [Mainz Univ. (Germany). PRISMA Cluster of Excellence; DESY, Hamburg (Germany). Theory Group; Teubner, Thomas [Liverpool Univ. (United Kingdom). Dept. of Mathematical Sciences; Weiss, Christian [DESY, Hamburg (Germany). Theory Group; Siegen Univ. (Germany)

    2016-03-15

    We give a status report on the automation of next-to-leading order processes within the Monte Carlo event generator WHIZARD, using GoSam and OpenLoops as provider for one-loop matrix elements. To deal with divergences, WHIZARD uses automated FKS subtraction, and the phase space for singular regions is generated automatically. NLO examples for both scattering and decay processes with a focus on e{sup +}e{sup -} processes are shown. Also, first NLO-studies of observables for collisions of polarized leptons beams, e.g. at the ILC, will be presented. Furthermore, the automatic matching of the fixed-order NLO amplitudes with emissions from the parton shower within the POWHEG formalism inside WHIZARD will be discussed. We also present results for top pairs at threshold in lepton collisions, including matching between a resummed threshold calculation and fixed-order NLO. This allows the investigation of more exclusive differential observables.

  11. The chaotic effects in a nonlinear QCD evolution equation

    Science.gov (United States)

    Zhu, Wei; Shen, Zhenqi; Ruan, Jianhong

    2016-10-01

    The corrections of gluon fusion to the DGLAP and BFKL equations are discussed in a united partonic framework. The resulting nonlinear evolution equations are the well-known GLR-MQ-ZRS equation and a new evolution equation. Using the available saturation models as input, we find that the new evolution equation has the chaos solution with positive Lyapunov exponents in the perturbative range. We predict a new kind of shadowing caused by chaos, which blocks the QCD evolution in a critical small x range. The blocking effect in the evolution equation may explain the Abelian gluon assumption and even influence our expectations to the projected Large Hadron Electron Collider (LHeC), Very Large Hadron Collider (VLHC) and the upgrade (CppC) in a circular e+e- collider (SppC).

  12. Organic nanoclusters for nonlinear optics: from model systems to cooperative nanoassemblies with enhanced NLO responses

    Science.gov (United States)

    Terenziani, Francesca; Parthasarathy, Venkatakrishnan; Ghosh, Sampa; Pandey, Ravindra; Das, Puspendu K.; Blanchard-Desce, Mireille

    2009-08-01

    While structure-properties relationships are quite actively and successfully investigated at the molecular level of engineering of optical nonlinear responses, supramolecular structure-property relationships are an appealing field. The realization that interchromophoric interactions between strongly polar/polarizable NLO chromophores can significantly affect the NLO response of each chromophoric unit as well as promote associations has opened new dimensions for molecular design. Several elegant routes have been implemented to hinder or counterbalance dipole-dipole interactions between dipolar NLO chromophores for the elaboration of second-order materials (for SHG or electro-optical modulation). At opposite, we have implemented a reverse strategy by confining discrete numbers of NLO push-pull chromophores in close proximity within covalent organic nanoclusters with the aim to exploit interchromophoric interactions in order to achieve enhanced NLO responses. As a proof of concept, we present here the investigation of two-series of multichromophoric covalent assemblies built from NLO push-pull chromophores showing that cooperative enhancement can be achieved both for second-order optical responses (first hyperpolarizabilities) or third-order responses (two-photon absorption cross-sections).

  13. NLO+NLL squark and gluino production cross-sections with threshold-improved parton distributions

    CERN Document Server

    Beenakker, Wim; Krämer, Michael; Kulesza, Anna; Laenen, Eric; Marzani, Simone; Rojo, Juan

    2015-01-01

    We present updated predictions for the cross-sections for pair production of squarks and gluinos at the LHC Run II. First of all, we update the calculations based on NLO+NLL partonic cross-sections by using the NNPDF3.0NLO global analysis. This study includes a full characterization of theoretical uncertainties from higher orders, PDFs and the strong coupling. Then, we explore the implications for this calculation of the recent NNPDF3.0 PDFs with NLO+NLL threshold resummation. We find that the shift in the results induced by the threshold-improved PDFs is within the total theory uncertainty band of the calculation based on NLO PDFs. However, we also observe that the central values of the cross-sections are modified both in a qualitative and a quantitative way, illustrating the relevance and impact of using threshold-improved PDFs together with resummed partonic cross-sections. The updated NLO+NLL cross-sections based on NNPDF3.0NLO are publicly available in the NLL-fast format, and should be an important ingr...

  14. Fragmentation functions of neutral mesons π0 and k0 with Laplace transform approach

    Science.gov (United States)

    Taghavi-Shahri, F.; Tehrani, S. Atashbar; Zarei, M.

    2016-06-01

    With an analytical solutions of DGLAP evolution equations based on the Laplace transform method, we find the fragmentation functions (FFs) of neutral mesons, π0 and k0 at NLO approximation. We also calculated the total fragmentation functions of these mesons and compared them with experimental data and those from global fits. The results show a good agreement between our solutions and other models and they are compatible with experimental data.

  15. Fragmentation Functions of neutral mesons $\\pi^0$ and $k ^0$ with Laplace transform approach

    CERN Document Server

    Taghavi-Shahri, F; Zare, M

    2016-01-01

    With an analytical solutions of DGLAP evolution equations based on the Laplace transform method , we find the fragmentation functions (FFs) of neutral mesons, $\\pi^0$ and $k ^0$ at NLO approximation. We also calculated the total fragmentation functions of these mesons and compared them with experimental data and those from global fits. The results show a good agreements between our solutions and other models and also are compatible with experimental data.

  16. NLO uncertainties in Higgs+2 jets from gluon fusion

    Energy Technology Data Exchange (ETDEWEB)

    Gangal, Shireen; Tackmann, Frank J.

    2013-02-15

    A central ingredient in establishing the properties of the newly discovered Higgs-like boson is to isolate its production via vector boson fusion (VBF). With the typical experimental selection cuts, the VBF sample is contaminated by a {proportional_to} 25% fraction from Higgs+2 jet production via gluon fusion (ggF) which has large perturbative uncertainties. We perform a detailed study of the perturbative uncertainties in the NLO predictions for pp{yields}H+2 jets via ggF used by the ATLAS and CMS collaborations, with the VBF selection cuts of their current H{yields}{gamma}{gamma} analyses. We discuss in detail the application of the so-called ''ST method'' for estimating fixed-order perturbative uncertainties in this case, and also consider generalizations of it. Qualitatively, our results apply equally to other decay channels with similar VBF selection cuts. Typical VBF selections include indirect restrictions or explicit vetoes on additional jet activity, primarily to reduce non-Higgs backgrounds. We find that such restrictions have to be chosen carefully and are not necessarily beneficial for the purpose of distinguishing between the VBF and ggF production modes, since a modest reduction in the relative ggF contamination can be easily overwhelmed by its quickly increasing perturbative uncertainties.

  17. Functionalized organic frameworks explored as second order NLO agents

    Indian Academy of Sciences (India)

    Anil K Singh; Brijesh Rathi; Volodymyr V Medviediev; Oleg V Shishkin; Vijay Bahadur; Taruna Singh; Brajendra K Singh; N Vijayan; V Balachandran; Nikolay Yu Gorobets

    2016-02-01

    A new class of chiral phthalimides functionalized with aryl piperazines was designed anticipating their strong candidature for crystal engineering and technological applications. Five new phthalimides were synthesized, characterized and subjected to single crystal X-ray diffraction study that directed their noncentrosymmetric structures. Four phthalimides crystallized in 21 space group with monoclinic crystal system, however, one was found to possess 212121 space group with orthorhombic system. The supramolecular architectures of phthalimide crystals were analysed by an approach based on consideration of energy of intermolecular interaction. The molecular hyperpolarizability () calculation for all the listed phthalimides indicated their promising candidature for NLO materials. Further, the crystalline form of all phthalimides was evaluated for their second harmonic generation (SHG) response. A significant response of 16.4mV was measured for phthalimide possessing t-butyl substituent at the para position of 4-benzylpiperazine. This high SHG response may be attributed to the molecular chirality and helical supramolecular frameworks stabilized by C-H· · ·O hydrogen bonds in the solid state. The current study attests chiral phthalimides possessing arylpiperazines as effective nominees to the area of crystal engineering and nonlinear optics.

  18. Tuning the NLO properties of polymethineimine chains by chemical substitution

    Energy Technology Data Exchange (ETDEWEB)

    Medved’, Miroslav, E-mail: miroslav.medved@umb.sk [Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, SK-97400 Banská Bystrica (Slovakia); Jacquemin, Denis [CEISAM, UMR CNRS 6230, BP 92208, Université de Nantes, 2, rue de la Houssinière, 44322 Nantes Cedex 3 (France); Institut Universitaire de France, 103, bd Saint-Michel, F-75005 Paris Cedex 05 (France)

    2013-03-29

    Highlights: ► Properties of the most stable isomers of polymethineimine (PMI) are investigated. ► 2nd order NLO properties of experimentally known PMI derivatives are determined. ► Structure-property relationships are unraveled for several series of oligomers. ► Performance of long-range corrected DFT methods is assessed. - Abstract: Structure and molecular electronic properties including dipole moment, polarizability and first hyperpolarizability of polymethineimine (PMI) oligomers (up to hexadecamers) and its experimentally known amino-, methyl-, and cyano-derivatives are investigated using several ab initio methods (HF, MP2 and DFT). It is shown that side-chain substitutions have significant effects both on the structure and molecular properties of PMI chains. Depending on the substitution, two types of structures have been identified. The first is characterized by a bent skeleton and encompasses PMI, polyacetonitrile (PAcN), and polycyanonitrile (PCN). The second, represented by polyaminonitrile (PAN), remains quasi-linear with the plane of the unit cell (UC) only slightly rotating around the longitudinal molecular axis. These structural differences are also reflected in molecular properties; while in case of PMI, PAcN, and PCN the longitudinal component of properties (reduced per UC) reaches its maximum value for medium-size oligomers and then decreases for longer chains, the linear and nonlinear properties of PAN steadily increase towards the polymeric limit. In addition, we have assessed the performances of long-range corrected DFT functionals (LR-DFT), namely LC-BLYP, CAM-B3LYP, and ωB97X within the present framework: they provide results in qualitative agreement with MP2, a success not reached with B3LYP.

  19. NLO perturbativity bounds on quartic couplings in renormalizable theories with ϕ4-like scalar sectors

    Science.gov (United States)

    Murphy, Christopher W.

    2017-08-01

    The apparent breakdown of unitarity in low order perturbation theory is often is used to place bounds on the parameters of a theory. In this work we give an algorithm for approximately computing the next-to-leading order (NLO) perturbativity bounds on the quartic couplings of a renormalizable theory whose scalar sector is ϕ4-like. By this we mean theories where either there are no cubic scalar interactions, or the cubic couplings are related to the quartic couplings through spontaneous symmetry breaking. The quantity that tests where perturbation theory breaks down itself can be written as a perturbative series, and having the NLO terms allows one to test how well the series converges. We also present a simple example to illustrate the effect of considering these bounds at different orders in perturbation theory. For example, there is a noticeable difference in the viable parameter when the square of the NLO piece is included versus when it is not.

  20. QCD NLO with Powheg matching and top threshold matching in WHIZARD

    CERN Document Server

    Reuter, J; Chokoufe, B; Kilian, W; Stahlhofen, M; Weiss, C

    2016-01-01

    We present the status of the automation of NLO processes within the event generator WHIZARD. The program provides an automated FKS subtraction and phase space integration over the FKS regions, while the (QCD) NLO matrix element is accessed via the Binoth Les Houches Interface from an externally linked one-loop program. Massless and massive test cases and validation are shown for several e+e- processes. Furthermore, we discuss work in progress and future plans. The second part covers the matching of the NRQCD prediction with NLL threshold resummation to the NLO continuum top pair production at lepton colliders. Both the S-wave and P-wave production of the top pair are taken into account in the resummation. The inclusion in WHIZARD allows to study more exclusive observables than just the total cross section and automatically accounts for important electroweak and relativistic corrections in the threshold region.

  1. A golden A{sub 5} model of leptons with a minimal NLO correction

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, Iain K., E-mail: ikc1g08@soton.ac.uk; King, Stephen F., E-mail: king@soton.ac.uk; Stuart, Alexander J., E-mail: a.stuart@soton.ac.uk

    2013-10-21

    We propose a new A{sub 5} model of leptons which corrects the LO predictions of Golden Ratio mixing via a minimal NLO Majorana mass correction which completely breaks the original Klein symmetry of the neutrino mass matrix. The minimal nature of the NLO correction leads to a restricted and correlated range of the mixing angles allowing agreement within the one sigma range of recent global fits following the reactor angle measurement by Daya Bay and RENO. The minimal NLO correction also preserves the LO inverse neutrino mass sum rule leading to a neutrino mass spectrum that extends into the quasi-degenerate region allowing the model to be accessible to the current and future neutrinoless double beta decay experiments.

  2. Hadronic Higgs production through NLO+PS in the SM, the 2HDM and the MSSM

    CERN Document Server

    Mantler, Hendrik

    2015-01-01

    The NLO cross section of the gluon fusion process is matched to parton showers in the MC@NLO approach. We work in the framework of MadGraph5_aMC@NLO and document the inclusion of the full quark-mass dependence in the SM as well as the state-of-the-art squark and gluino effects within the MSSM embodied in the program SusHi. The combination of the two programs is realized by a script which is publicly available and whose usage is detailed. We discuss the input cards and the relevant parameter switches. One of our focuses is on the shower scale which is specifically important for gluon-induced Higgs production, particularly in models with enhanced Higgs-bottom Yukawa coupling.

  3. NLO+NLL limits on $W'$ and $Z'$ gauge boson masses

    CERN Document Server

    Ježo, Tomáš; Lamprea, David R; Lyonnet, Florian; Schienbein, Ingo

    2015-01-01

    QCD resummation predictions for the production of new charged ($W'$) and neutral ($Z'$) heavy gauge bosons decaying leptonically are presented. These results are obtained with our resummation code at next-to-leading order and next-to-leading logarithmic (NLO+NLL) accuracy. Our predictions are compared to PYTHIA at leading order (LO) supplemented with parton showers (PS) and FEWZ at NLO and next-to-next-to-leading order (NNLO) for the $p_T$-differential and total cross sections in the Sequential Standard Model (SSM) and general SU(2)$\\times$SU(2)$\\times$U(1) models. We show that the importance of resummation for total cross sections increases with the gauge boson mass. Finally, the latest ATLAS and CMS results are reinterpreted to derive new limits at NLO+NLL on $W'$ and $Z'$ boson masses in general extensions of the Standard Model.

  4. NLO corrections to c - and b -quark fragmentation into j /ψ and γ

    Science.gov (United States)

    Sepahvand, R.; Dadfar, S.

    2017-02-01

    We present the next-to-leading-order (NLO) corrections to the fragmentation process of a heavy quark to a 3S1 wave heavy quarkonium. The virtual and real corrections are calculated by using the dimensional regularization method. The divergences due to virtual NLO corrections are analytically extracted then we explain how the poles from phase-space integrals and from loop integrals are canceled by renormalization. We use the eikonal scheme to evaluate the soft real corrections in 4 -2 ɛ dimensions. Our numerical calculations show the fragmentation function (FF) at NLO is dependent on both the μ scale and the initial quark energy. These corrections have a significant effect on the shape and probability of the FF.

  5. Higgs boson pair production in gluon fusion at NLO with full top-quark mass dependence

    CERN Document Server

    Borowka, S; Heinrich, G; Jones, S P; Kerner, M; Schlenk, J; Schubert, U; Zirke, T

    2016-01-01

    We present the calculation of the cross section and invariant mass distribution for Higgs boson pair production in gluon fusion at next-to-leading order (NLO) in QCD. Top-quark masses are fully taken into account throughout the calculation. The virtual two-loop amplitude has been generated using an extension of the program GoSam supplemented with an interface to Reduze for the integral reduction. The occurring integrals have been calculated numerically using the program SecDec. Our results, including the full top-quark mass dependence for the first time, allow us to assess the validity of various approximations proposed in the literature, which we also recalculate. We find substantial deviations between the NLO result and the different approximations, which emphasizes the importance of including the full top-quark mass dependence at NLO.

  6. QCD NLO with POWHEG matching and top threshold matching in WHIZARD

    Energy Technology Data Exchange (ETDEWEB)

    Reuter, Juergen; Nejad, Bijan Chokoufe [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Bach, Fabian [European Commission, Luxembourg (Luxembourg); Kilian, Wolfgang [Siegen Univ. (Germany); Stahlhofen, Maximilian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Mainz Univ. (Germany). PRISMA Cluster of Excellence; Weiss, Christian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Siegen Univ. (Germany)

    2016-01-15

    We present the status of the automation of NLO processes within the event generator WHIZARD. The program provides an automated FKS subtraction and phase space integration over the FKS regions, while the (QCD) NLO matrix element is accessed via the Binoth Les Houches Interface from an externally linked one-loop program. Massless and massive test cases and validation are shown for several e{sup +}e{sup -} processes. Furthermore, we discuss work in progress and future plans. The second part covers the matching of the NRQCD prediction with NLL threshold resummation to the NLO continuum top pair production at lepton colliders. Both the S-wave and P-wave production of the top pair are taken into account in the resummation. The inclusion in WHIZARD allows to study more exclusive observables than just the total cross section and automatically accounts for important electroweak and relativistic corrections in the threshold region.

  7. NLO QCD corrections to Higgs boson production plus three jets in gluon fusion

    Energy Technology Data Exchange (ETDEWEB)

    Cullen, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Deurzen, H. van; Greiner, N.; Luisoni, G.; Mirabella, E.; Peraro, T. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Mastrolia, P. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Padova Univ. (Italy). Dipt. di Fisica e Astronomia; INFN, Sezione di Padova (Italy); Ossola, G. [New York Univ., NY (United States). New York City College of Technology; New York Univ., NY (United States). The Graduate School and University Center; Tramontano, F. [Napoli Univ. (Italy). Dipt. di Fisica; INFN, Sezione di Napoli (Italy)

    2013-07-15

    We report on the calculation of the cross section for Higgs boson production in association with three jets via gluon fusion, at next-to-leading-order (NLO) accuracy in QCD, in the infinite top-mass approximation. After including the complete NLO QCD corrections, we observe a strong reduction in the scale dependence of the result, and an increased steepness in the transverse momentum distributions of both the Higgs and the leading jets. The results are obtained with the combined use of GoSam, Sherpa, and the MadDipole/MadEvent framework.

  8. Synthesis and Non-linear Optical(NLO) Properties of a Series of Alkoxysilane Derivative Chromophores

    Institute of Scientific and Technical Information of China (English)

    SHI Zuo-sen; ZHANG Xiao-long; WANG Shi-wei; ZHAO Li-sha; CUI Zhan-chen

    2009-01-01

    @@ 1 Introduction Nonlinear optical materials(NLO) have drawn a great intrest of some scholars and scientists in the last dacades because of their tremendous potential application in optoelectronic~[1]. The fabrication of efficient optoelectron devices is a challenging task because such systems need to meet the stringentable requirements for high optical quality and large and sustainable electro-optical(EO) response[2]. In pursuit of NLO materials with excellent optoelectronic property, a number of organic and inorganic materials have been investigated. Among them, organic-inorganic hybrid materials have drawn a great interest due to their good thermal stabilities, low optical loss and convenience in fabricating their thin films[3-6].

  9. NLO QCD Corrections for $\\chi_{cJ}$ Inclusive Production at $B$ Factories

    CERN Document Server

    Chen, Long-Bin; Qiao, Cong-Feng

    2014-01-01

    The next-to-leading order (NLO) quantum chromodynamics (QCD) corrections for $\\chi_{cJ}(^3P_J^{[1]},^3S_1^{[8]})$, the P-wave charmoniums inclusive production at $B$ factories are calculated utilizing the non-relativistic QCD (NRQCD) factorization formalism. Large NLO corrections are found, especially for $^3P_0^{[1]}$ and $^3S_1^{[8]}$ configurations. Numerical evaluation indicates that the total cross sections of $\\chi_{cJ}+c+\\bar{c}$ processes are about $1\\sim100$fb, which are accessible in the super-B experiment.

  10. NLO K-factors for Single-Inclusive Leptoproduction of Hadrons

    CERN Document Server

    Schlegel, Marc; Vogelsang, Werner

    2015-01-01

    In these proceedings we discuss next-to-leading order (NLO) perturbative-QCD calculations of the cross section for the process $\\ell N\\to h X$. We briefly present the main features of the calculation and in particular analyze the role of quasi-real photons that enter the processes because the scattered lepton is not observed. We find that the NLO corrections are sizable for the spin-averaged cross section. In order to quantify this statement we present the K-factors of the cross sections for fixed target experiments HERMES, JLab12 and COMPASS.

  11. The NLO QCD corrections to associate production of squarks and charginos at LHC

    Science.gov (United States)

    Xiao, Zhen-Jun; Jin, Li-Gang; Yu, Huan; Cheng, Hong-Mei

    2010-02-01

    In this talk, we present our calculations for the next-to-leading order(NLO) QCD corrections to the cross sections (CS) of the associate production processes pp→gq→q˜iχ˜j±+X with q = (u,d) in the constrained minimal supersymmetric standard model in the CERN LHC experiments. The NLO QCD corrections can in general provide a 30-40% enhancement to the corresponding cross sections, and significantly reduce the dependence of the total cross section on the renormalization and factorization scales.

  12. Triple vector boson production through Higgs-Strahlung with NLO multijet merging

    CERN Document Server

    Hoeche, S.; Pozzorini, S.; Schoenherr, M.; Thompson, J.M.; Zapp, K.C.

    2014-01-01

    Triple gauge boson hadroproduction, in particular the production of three $W$-bosons at the LHC, is considered at next-to leading order accuracy in QCD. The NLO matrix elements are combined with parton showers. Multijet merging is invoked such that NLO matrix elements with one additional jet are also included. The studies here incorporate both the signal and all relevant backgrounds for $VH$ production with the subsequent decay of the Higgs boson into $W$-- or $\\tau$--\\-pairs. They have been performed using \\SherpaOpenLoops in combination with Collier.

  13. NLO QCD analysis of single-diffractive dijet production at the Tevatron

    Science.gov (United States)

    Klasen, M.

    We present the first NLO QCD analysis of single-diffractive dijet production in proton-antiproton collisions. By comparing the ratio of single- and non-diffractive cross sections to data from the Tevatron, the rapidity-gap survival probability is determined as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at NLO.

  14. NLO QCD analysis of single-diffractive dijet production at the Tevatron

    CERN Document Server

    Klasen, M

    2010-01-01

    We present the first NLO QCD analysis of single-diffractive dijet production in proton-antiproton collisions. By comparing the ratio of single- and non-diffractive cross sections to data from the Tevatron, the rapidity-gap survival probability is determined as a function of the momentum fraction of the parton in the antiproton. Assuming Regge factorization, this probability can be interpreted as a suppression factor for the diffractive structure function measured in deep-inelastic scattering at HERA. In contrast to the observations for photoproduction, the suppression factor in proton-antiproton collisions depends on the momentum fraction of the parton in the Pomeron even at NLO.

  15. On the maximal use of Monte Carlo samples: re-weighting events at NLO accuracy

    Science.gov (United States)

    Mattelaer, Olivier

    2016-12-01

    Accurate Monte Carlo simulations for high-energy events at CERN's Large Hadron Collider, are very expensive, both from the computing and storage points of view. We describe a method that allows to consistently re-use parton-level samples accurate up to NLO in QCD under different theoretical hypotheses. We implement it in MadGraph5_aMC@NLO and show its validation by applying it to several cases of practical interest for the search of new physics at the LHC.

  16. The SM and NLO Multileg and SM MC Working Groups: Summary Report

    CERN Document Server

    Alcaraz Maestre, J.; Huston, J.; Krauss, F.; Maitre, D.; Nurse, E.; Pittau, R.; Alioli, S.; Andersen, J.R.; Ball, R.D.; Buckley, A.; Cacciari, M.; Campanario, F.; Chanon, N.; Chachamis, G.; Ciulli, V.; Cossutti, F.; Cullen, G.; Denner, A.; Dittmaier, S.; Fleischer, J.; Frederix, R.; Frixione, S.; Gao, J.; Garren, L.; Gascon-Shotkin, S.; Greiner, N.; Guillet, J.P.; Hapola, T.; Hartland, N.P.; Hesketh, G.; Hirschi, V.; Hoeth, H.; Jezo, T.; Kallweit, S.; Kovarik, K.; Kusina, A.; Liang, Z.; Lenzi, P.; Lonnblad, L.; Lopez-Villarejo, J.J.; Luisoni, G.; Maltoni, F.; Mastrolia, P.; Nadolsky, P.M.; Oleari, C.; Olness, F.I.; Ossola, G.; Pilon, E.; Platzer, S.; Pozzorini, S.; Prestel, S.; Re, E.; Reiter, T.; Riemann, T.; Rojo, J.; Salam, G.P.; Sapeta, S.; Schienbein, I.; Schonherr, M.; Schulz, H.; Schulze, M.; Schwoerer, M.; Skands, P.; Smillie, J.M.; Somogyi, G.; Soyez, G.; Stavreva, T.; Stewart, I.W.; Stockton, M.; or, Z.Sz\\H.; Tackmann, F.J.; Torrielli, P.; Tramontano, F.; Tripiana, M.; Trocsanyi, Z.; Ubiali, M.; Yundin, V.; Weinzierl, S.; Winter, J.; Yu, J.Y.; Zapp, K.

    2012-01-01

    The 2011 Les Houches workshop was the first to confront LHC data. In the two years since the previous workshop there have been significant advances in both soft and hard QCD, particularly in the areas of multi-leg NLO calculations, the inclusion of those NLO calculations into parton shower Monte Carlos, and the tuning of the non-perturbative parameters of those Monte Carlos. These proceedings describe the theoretical advances that have taken place, the impact of the early LHC data, and the areas for future development.

  17. Triple vector boson production through Higgs-Strahlung with NLO multijet merging

    Energy Technology Data Exchange (ETDEWEB)

    Hoeche, S.; /SLAC; Krauss, F.; /Durham U., IPPP; Pozzorini, S.; /Zurich U.; Schonherr, M.; Thompson, J.M.; /Durham U., IPPP; Zapp, K.C.; /CERN

    2014-07-25

    Triple gauge boson hadroproduction, in particular the production of three W-bosons at the LHC, is considered at next-to leading order accuracy in QCD. The NLO matrix elements are combined with parton showers. Multijet merging is invoked such that NLO matrix elements with one additional jet are also included. The studies here incorporate both the signal and all relevant backgrounds for V H production with the subsequent decay of the Higgs boson into W– or τ–- pairs. They have been performed using SHERPA+OPENLOOPS in combination with COLLIER.

  18. Erratum for the time-like evolution in QCDNUM

    CERN Document Server

    Botje, M

    2016-01-01

    A recent comparison of the evolution programs QCDNUM and APFEL showed a discrepancy in the time-like evolution of the singlet fragmentation function at NLO. It was found that the splitting functions of this evolution were wrongly assigned in QCDNUM, and also that the fragmentation functions were not correctly matched at the flavour thresholds. These errors are corrected in a new release of the program.

  19. Global extraction of the parton-to-pion fragmentation functions at NLO accuracy in QCD

    CERN Document Server

    Hernández-Pinto, R J; de Florian, D; Sassot, R; Stratmann, M

    2016-01-01

    In this review, we discuss the results on the parton-to-pion fragmentation functions obtained in a combined NLO fit to data of single-inclusive hadron production in electron-positron annihilation, proton-proton collisions, and lepton-nucleon deep-inelastic scattering. A more complete discussion can be found in Ref. [1].

  20. Single slepton production associated with a top quark at LHC in NLO QCD

    CERN Document Server

    Xiao-Peng, Li; Wen-Gan, Ma; Liang, Han; Ren-You, Zhang; Shao-Ming, Wang

    2012-01-01

    Single slepton production in association with a top quark at the CERN Large Hadron Collider (LHC) is one of the important processes in probing the R-parity violation couplings. We calculate the QCD next-to-leading order (NLO) corrections to the $pp \\to t\\slep^{-}(\\bar{t}\\slep^{+})+X$ process at the LHC and discuss the impacts of the QCD corrections on kinematic distributions. We investigate the dependence of the leading order (LO) and the NLO QCD corrected integrated cross section on the factorization/renormalization energy scale, slepton, stop-quark and gluino masses. We find that the uncertainty of the LO cross section due to the energy scale is obviously improved by the NLO QCD corrections, and the exclusive jet event selection scheme keeps the convergence of the perturbative series better than inclusive scheme. The results show that the polarization asymmetry of the top-quark will be reduced by the NLO QCD corrections, and the QCD corrections generally increase with the increment of $\\tilde{t}_1$ or $\\til...

  1. W gamma production in hadronic collisions using the POWHEG+MiNLO method

    CERN Document Server

    Barze, Luca; Montagna, Guido; Nason, Paolo; Nicrosini, Oreste; Piccinini, Fulvio; Prosperi, Valeria

    2014-01-01

    We detail a calculation of W gamma production in hadronic collision, at Next-to-Leading Order (NLO) QCD interfaced to a shower generator according to the POWHEG prescription supplemented with the MiNLO procedure. The fixed order result is matched to an interleaved QCD+QED parton shower, in such a way that the contribution arising from hadron fragmentation into photons is fully modeled. In general, our calculation illustrates a new approach to the fully exclusive simulation of prompt photon production processes accurate at the NLO level in QCD. We compare our predictions to those of the NLO program MCFM, which treats the fragmentation contribution in terms of photon fragmentation functions. We also perform comparisons to available LHC data at 7 TeV, for which we observe good agreement, and provide phenomenological results for physics studies of the W gamma production process at the Run II of the LHC. The new tool, which includes W leptonic decays and the contribution of anomalous gauge couplings, allows a full...

  2. NLO QCD corrections to off-shell ttj production at the LHC

    CERN Document Server

    Worek, Malgorzata

    2016-01-01

    A short summary of results for top-quark pair production in association with a jet with NLO QCD off-shell effects at the LHC is given. The calculation is based on the matrix element for the $pp \\to e^+ \

  3. $HZ$ associated production at the LHC within the littlest Higgs model at NLO+NLL accuracy

    CERN Document Server

    Liang-Wen, Chen; Ren-You, Zhang; Xiao-Zhou, Li; Yong, Wang

    2016-01-01

    We consider the $HZ$ associated production at the $14~{\\rm TeV}$ LHC in the littlest Higgs model (LHM) and study the corrections of the transverse momentum resummation and threshold resummation at the next-to-leading logarithmic (NLL) accuracy and the fixed-order prediction at the QCD next-to-leading order (NLO) including the contribution from the one-loop-induced $gg$-fusion channel. The QCD NLO+NLL effects on the integrated cross section and the distributions of transverse momentum and invariant mass of the $HZ$ system for the $HZ$ production in the LHM are discussed. The distributions of transverse momentum and invariant mass of the $HZ$ system are evaluated by means of the transverse momentum resummation and threshold resummation, respectively. We estimate their scale uncertainties and find that the predictions obtained at the QCD NLO+NLL accuracy are much more reliable than those using the pure NLO approach. We see also that the relative deviation between the results in the LHM and the standard model is ...

  4. X-Ray Diffraction Analysis of NLO Crystals: Traditional Applications and More New Opportunities

    Science.gov (United States)

    Antipin, Mikhail Yu.; Clark, Ronald D.; Nesterov, Vladimir N.

    1998-01-01

    Single crystal X-ray diffraction analysis is one of the more important methods for the molecular and crystal structure determination of matter and therefore it has a great importance in material science including design and engineering of different compounds with non-linear optical (NLO) properties. It was shown in our previous publications that this method provides unique information about molecular structure of NLO compounds, their crystal symmetry and crystal packing arrays, molecular conformation and geometries and many other structural and electronic characteristics that are important for understanding the nature of NLO properties of solids. A very new application of the X-ray diffraction method is related to analysis of the electron density distribution p(r) in crystals and some of its characteristics (atomic and group charges, dipole and higher multipole moments, etc.), that may be obtained directly form the diffraction measurements. In the present work, we will discuss our preliminary low temperature high-resolution X-ray data for the m-nitroaniline (mNA) single crystal (VI). This is one of the "classical" organic NLO materials and electron density distribution analysis in this simple compound has a great scientific interest.

  5. A general framework for implementing NLO calculations in shower Monte Carlo programs. The POWHEG BOX

    Energy Technology Data Exchange (ETDEWEB)

    Alioli, Simone [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Nason, Paolo [INFN, Milano-Bicocca (Italy); Oleari, Carlo [INFN, Milano-Bicocca (Italy); Milano-Bicocca Univ. (Italy); Re, Emanuele [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology

    2010-02-15

    In this work we illustrate the POWHEG BOX, a general computer code framework for implementing NLO calculations in shower Monte Carlo programs according to the POWHEG method. Aim of this work is to provide an illustration of the needed theoretical ingredients, a view of how the code is organized and a description of what a user should provide in order to use it. (orig.)

  6. The in-medium scale evolution in jet modification

    CERN Document Server

    Majumder, A

    2009-01-01

    The in-medium modification of the scale dependence of the fragmentation function in dense matter, brought about by higher twist corrections to the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations, is derived. A phenomenologically motivated resummation is outlined which incorporates the next-to-leading twist single gluon emission kernel along with the vacuum emission kernel and provides an in-medium virtuality evolution of the final fragmentation function of a hard jet propagating through dense matter. The concept of a fragmentation function is generalized to include a dependence on distance travelled in the medium. Following this, numerical implementations are carried out and compared to experimental results on the single inclusive suppression observed in Deep-Inelastic scattering (DIS) off a large nucleus.

  7. Charged Higgs boson production in association with a top quark in MC {sup rate} {sup at} NLO

    Energy Technology Data Exchange (ETDEWEB)

    Weydert, C.; Klasen, M. [UJF, CNRS/IN2P3, INPG, Laboratoire de Physique Subatomique et de Cosmologie, Grenoble cedex (France); Frixione, S. [CERN, PH Department, TH unit, Geneva 23 (Switzerland); EPFL, ITPP, Lausanne (Switzerland); Herquet, M. [Nikhef Theory Group, Amsterdam (Netherlands); Laenen, E. [Nikhef Theory Group, Amsterdam (Netherlands); University of Amsterdam, Institute for Theoretical Physics, Amsterdam (Netherlands); Utrecht University, Institute for Theoretical Physics, Utrecht (Netherlands); Plehn, T. [Universitaet Heidelberg, Institut fuer Theoretische Physik, Heidelberg (Germany); Stavenga, G. [Utrecht University, Institute for Theoretical Physics, Utrecht (Netherlands); Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL (United States); White, C.D. [Durham University, Institute for Particle Physics Phenomenology, Department of Physics, Durham, DH1 3LE (United Kingdom)

    2010-06-15

    We discuss the calculation of charged Higgs boson production in association with a top quark in the MC {sup rate} {sup at} NLO framework for combining NLO matrix elements with a parton shower. The process is defined in a model-independent manner for wide applicability, and can be used if the charged Higgs boson mass is either greater or less than the mass of the top quark. For the latter mass region, care is needed in defining the charged Higgs production mode due to interference with top pair production. We give a suitable definition applicable in an NLO (plus parton shower) context, and we present example results for the LHC. (orig.)

  8. Jet quenching from QCD evolution

    Science.gov (United States)

    Chien, Yang-Ting; Emerman, Alexander; Kang, Zhong-Bo; Ovanesyan, Grigory; Vitev, Ivan

    2016-04-01

    Recent advances in soft-collinear effective theory with Glauber gluons have led to the development of a new method that gives a unified description of inclusive hadron production in reactions with nucleons and heavy nuclei. We show how this approach, based on the generalization of the DGLAP evolution equations to include final-state medium-induced parton shower corrections for large Q2 processes, can be combined with initial-state effects for applications to jet quenching phenomenology. We demonstrate that the traditional parton energy loss calculations can be regarded as a special soft-gluon emission limit of the general QCD evolution framework. We present phenomenological comparison of the SCETG -based results on the suppression of inclusive charged hadron and neutral pion production in √{sNN }=2.76 TeV lead-lead collisions at the Large Hadron Collider to experimental data. We also show theoretical predictions for the upcoming √{sNN }≃5.1 TeV Pb +Pb run at the LHC.

  9. Measurement-Based LoS/NLoS Channel Modeling for Hot-Spot Urban Scenarios in UMTS Networks

    Directory of Open Access Journals (Sweden)

    Jiajing Chen

    2014-01-01

    Full Text Available A measurement campaign is introduced for modeling radio channels with either line-of-sight (LoS or non-line-of-sight (NLoS connection between user equipment (UE and NodeB (NB in an operating universal mobile telecommunications system. A space-alternating generalized expectation-maximization (SAGE algorithm is applied to estimate the delays and the complex attenuations of multipath components from the obtained channel impulse responses. Based on a novel LoS detection method of multipath parameter estimates, channels are classified into LoS and NLoS categories. Deterministic models which are named “channel maps” and fading statistical models have been constructed for LoS and NLoS, respectively. In addition, statistics of new parameters, such as the distance between the NB and the UE in LoS/NLoS scenarios, the life-distance of LoS channel, the LoS existence probability per location and per NB, the power variation at LoS to NLoS transition and vice versa, and the transition duration, are extracted. These models are applicable for designing and performance evaluation of transmission techniques or systems used by distinguishing the LoS and NLoS channels.

  10. Monte Carlo simulations of Higgs-boson production at the LHC with the KrkNLO method

    CERN Document Server

    Jadach, S.

    2017-01-01

    We present numerical tests and predictions of the KrkNLO method for matching of NLO QCD corrections to hard processes with LO parton shower Monte Carlo generators. This method was described in detail in our previous publications, where its advantages over other approaches, such as MCatNLO and POWHEG, were pointed out. Here we concentrate on presenting some numerical results (cross sections and distributions) for $Z/\\gamma^*$ (Drell-Yan) and Higgs-boson production processes at the LHC. The Drell--Yan process is used mainly to validate the KrkNLO implementation in the Herwig 7 program with respect to the previous implementation in Sherpa. We also show predictions for this process with the new, complete, MC-scheme parton distribution functions and compare them with our previously published results. Then, we present the first results of the KrkNLO method for the Higgs production in gluon--gluon fusion at the LHC and compare them with the predictions of other programs, such as MCFM, MCatNLO, POWHEG and HNNLO, as w...

  11. Monte Carlo simulations of Higgs-boson production at the LHC with the KrkNLO method

    CERN Document Server

    Jadach, S; Placzek, W; Sapeta, S; Siodmok, A; Skrzypek, M

    2016-01-01

    We present numerical tests and predictions of the KrkNLO method for matching of NLO QCD corrections to hard processes with LO parton shower Monte Carlo generators. This method was described in detail in our previous publications, where its advantages over other approaches, such as MCatNLO and POWHEG, were pointed out. Here we concentrate on presenting some numerical results (cross sections and distributions) for $Z/\\gamma^*$ (Drell-Yan) and Higgs-boson production processes at the LHC. The Drell--Yan process is used mainly to validate the KrkNLO implementation in the Herwig 7 program with respect to the previous implementation in Sherpa. We also show predictions for this process with the new, complete, MC-scheme parton distribution functions and compare them with our previously published results. Then, we present the first results of the KrkNLO method for the Higgs production in gluon--gluon fusion at the LHC and compare them with the predictions of other programs, such as MCFM, MCatNLO, POWHEG and HNNLO, as w...

  12. High multiplicity processes at NLO with BlackHat and Sherpa

    CERN Document Server

    Bern, Zvi; Dixon, Lance J; Hoeche, Stefan; Cordero, Fernando Febres; Ita, Harald; Kosower, David; Maître, Daniel

    2012-01-01

    In this contribution we review recent progress with fixed-order QCD predictions for the production of a vector boson in association with jets at hadron colliders, using the programs BlackHat and SHERPA. We review general features of next-to-leading-order (NLO) predictions for the production of a massive vector boson in association with four jets. We also discuss how precise descriptions of vector-boson production can be applied to the determination of backgrounds to new physics signals. Here we focus on data-driven backgrounds to a missing-energy-plus-jets search performed by CMS. Finally, we review recent progress in developing theoretical tools for high-multiplicity loop-computation within the BlackHat-library. In particular, we discuss methods for handling the color degrees of freedom in multi-jet predictions at NLO.

  13. Higgs characterisation at NLO in QCD: CP properties of the top-quark Yukawa interaction.

    Science.gov (United States)

    Demartin, Federico; Maltoni, Fabio; Mawatari, Kentarou; Page, Ben; Zaro, Marco

    At the LHC the CP properties of the top-quark Yukawa interaction can be probed through Higgs production in gluon fusion or in association with top quarks. We consider the possibility for both CP-even and CP-odd couplings to the top quark to be present, and study CP-sensitive observables at next-to-leading order (NLO) in QCD, including parton-shower effects. We show that the inclusion of NLO corrections sizeably reduces the theoretical uncertainties, and confirm that di-jet correlations in [Formula: see text] jet production through gluon fusion and correlations of the top-quark decay products in [Formula: see text] production can provide sensitive probes of the CP nature of the Higgs interactions.

  14. Kaluza-Klein gluons at 100 TeV: NLO corrections

    CERN Document Server

    Lillard, Benjamin; Tanedo, Philip

    2016-01-01

    We explore the reach of a 100 TeV proton collider to discover KK gluons in a warped extra dimension. These particles are templates for color adjoint vectors that couple dominantly to the top quark. We examine their production rate at NLO in the six-flavor m-ACOT scheme for a variety of reference models defining their coupling to quarks, largely inspired by the RS model of a warped extra dimension. In agreement with previous calculations aimed at lower energy machines, we find that the NLO corrections are typically negative, resulting in a $K$-factor of around 0.7 (depending on the model) and with a residual scale dependence on the order of $\\pm 20\\%$, greater than the variation from the scale exhibited by the na\\"{i}ve LO estimate.

  15. Jet-Medium Interactions at NLO in a Weakly-Coupled Quark-Gluon Plasma

    CERN Document Server

    Ghiglieri, Jacopo; Teaney, Derek

    2015-01-01

    We present an extension to next-to-leading order in the strong coupling constant $g$ of the AMY effective kinetic approach to the energy loss of high momentum particles in the quark-gluon plasma. At leading order, the transport of jet-like particles is determined by elastic scattering with the thermal constituents, and by inelastic collinear splittings induced by the medium. We reorganize this description into collinear splittings, high-momentum-transfer scatterings, drag and diffusion, and particle conversions (momentum-preserving identity-changing processes). We show that this reorganized description remains valid to NLO in $g$, and compute the appropriate modifications of the drag, diffusion, particle conversion, and inelastic splitting coefficients. In addition, a new kinematic regime opens at NLO for wider-angle collinear bremsstrahlung. These semi-collinear emissions smoothly interpolate between the leading order high-momentum-transfer scatterings and collinear splittings. To organize the calculation, w...

  16. $W^+W^-$ + 3 Jet Production at the Large Hadron Collider in NLO QCD

    CERN Document Server

    Cordero, F Febres; Ita, H

    2015-01-01

    We present next-to-leading order (NLO) QCD predictions to $W^+W^-$ production in association with up to three jets at hadron colliders. We include contributions from couplings of the $W$ bosons to light quarks as well as trilinear vector couplings. These processes are used in vector-boson coupling measurements, are background to Higgs signals and are needed to constrain many new physics scenarios. For the first time NLO QCD predictions are shown for electroweak di-vector boson production with three jets at a hadron collider. We show total and differential cross sections for the LHC with proton center-of-mass energies of 8 and 13 TeV. To perform the calculation we employ on-shell and unitarity methods implemented in the BlackHat library along with the SHERPA package. We have produced event files that can be accessed for future dedicated studies.

  17. NLO QCD Corrections to the Polarized Photo- and Hadroproduction of Heavy Quarks

    CERN Document Server

    Bojak, I

    2000-01-01

    The complete details of our calculation of the NLO QCD corrections to heavy flavor photo- and hadroproduction with longitudinally polarized initial states are presented. The main motivation for investigating these processes is the determination of the polarized gluon density at the COMPASS and RHIC experiments, respectively, in the near future. All methods used in the computation are extensively documented, providing a self-contained introduction to this type of calculations. Some employed tools also may be of general interest, e.g., the series expansion of hypergeometric functions. The relevant parton level results are collected and plotted in the form of scaling functions. However, the simplification of the obtained gluon-gluon virtual contributions has not been completed yet. Thus NLO phenomenological predictions are only given in the case of photoproduction. The theoretical uncertainties of these predictions, in particular with respect to the heavy quark mass, are carefully considered. Also it is shown th...

  18. DFT calculations on spectroscopic, structural and NLO properties of silver (I) complex with picolinamide

    Science.gov (United States)

    Altürk, Sümeyye; Avci, Davut; Tamer, Ömer; Atalay, Yusuf

    2017-02-01

    The molecular geometry optimization, vibrational frequencies, the molecular static polarizability (α), first-order static hyperpolarizability (β), second-order static hyperpolarizability (γ) and frontier molecular orbital (FMO) energies of silver (I) complex with picolinamide, [Ag(C6H6N2O)2](NO3).H2O, were investigated using density functional theory (DFT) HSEh1PBE and B3LYP methods with LANL2DZ basis set. The molecular hardness (η) and electronegativity (χ) parameters were also obtained by using FMO energies. The NLO parameters of the complex were compared with those of para-Nitroaniline (pNA) and urea which are typical NLO materials. Obtained data showed that there is an agreement between the predicted and experimental data.

  19. Comparisons of select ATLAS $t\\bar{t}$ differential distributions with various NLO predictions

    CERN Document Server

    The ATLAS collaboration

    2013-01-01

    Differential $t\\bar{t}$ cross-section results have been published by the ATLAS experiment at the LHC for a variety of kinematic distributions using an integrated luminosity of 2 ${\\rm fb}^{-1}$ proton-proton collision data collected at a center-of-mass energy of $\\sqrt{s} = 7$ TeV. Some of these distributions can potentially be used to improve the precision of the parton distribution functions. In this document we compare select differential spectra with predictions determined at NLO QCD using the MCFM program and accounting for a wide variety of theoretical systematic uncertainties. The data are compared with each of the following PDF models with NLO accuracy: CT10, MSTW 2008, NNPDF 2.3, HERAPDF1.5, and ABM11.

  20. AC and DC Electrical Conductivity Measurements on Glycine Family of Nonlinear Optical (NLO Single Crystals

    Directory of Open Access Journals (Sweden)

    Suresh Sagadevan

    2014-04-01

    Full Text Available In the present work, the AC/DC conductivity studies were carried out on Glycine family of NLO single crystals such as Trisglycine Zinc Chloride (TGZC, Triglycine Acetate (TGAc and Glycine Lithium Sulphate (GLS. The AC conductivity measurements were carried out using HIOKI 3532-50 LCR HITESTER in the frequency range of 50 Hz to 5 MHz for the grown NLO single crystals. The DC electrical conductivity measurements were also carried out for the crystals using the conventional two – probe technique in the temperature range of 313 – 423 K. The present study indicates that both the AC and DC conductivity of the samples increase with the increase in temperature. The activation energies were also calculated from AC/DC conductivity studies.

  1. A DFT study on NLO response of push-pull hybrid porphyrin-polyoxometalate complexes

    Science.gov (United States)

    Yao, Chan; Hu, Bo; Wang, Qingwei; Song, Ping; Su, Zhongmin

    2014-06-01

    Density functional theory (DFT) calculations were carried out to investigate the second-order nonlinear optical (NLO) properties of a series of proposed porphyrin-polyoxometalate-based complexes related to [5-(3,5-dimethyl-4-hexamolybdate amino-phenyl-ethynyl)-15-(4-nitrophenyl-ethynyl)porphinato]zinc(II) which have donor-π conjugated bridge-acceptor (D-π-A) configurations. Our calculations show that these species possess considerably large molecular total second-order polarizability (β0), ˜2000 × 10-30 esu. Furthermore, it can be seen that {W6O18} exhibits stronger electron-donating ability than {Mo6O18}. And two-dimensional (2D) system with A-π-D-π-A structure might be a promising candidate for NLO materials based on the large β0 (4583.5 × 10-30 esu) and in-plane nonlinear anisotropy.

  2. Electroweakino pair production at the LHC: NLO SUSY-QCD corrections and parton-shower effects

    CERN Document Server

    Baglio, Julien; Kesenheimer, Matthias

    2016-01-01

    We present a set of NLO SUSY-QCD calculations for the pair production of neutralinos and charginos at the LHC, and their matching to parton-shower programs in the framework of the POWHEG-BOX program package. The code we have developed provides a SUSY Les Houches Accord interface for setting supersymmetric input parameters. Decays of the neutralinos and charginos and parton-shower effects can be simulated with PYTHIA. To illustrate the capabilities of our program, we present phenomenological results for a representative SUSY parameter point. We find that NLO-QCD corrections increase the production rates for neutralinos and charginos significantly. The impact of parton-shower effects on distributions of the weakinos is small, but non-negligible for jet distributions.

  3. NNLO massive corrections to Bhabha scattering and theoretical precision of BabaYaga rate at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Carloni Calame, C.M. [Southampton Univ. (United Kingdom). School of Physics; Czyz, H.; Gluza, J.; Gunia, M. [Silesia Univ., Katowice (Poland). Dept. of Field Theory and Particle Physics; Montagna, G. [Pavia Univ. (Italy). Dipt. di Fisica Nucleare e Teorica; INFN, Sezione di Pavia (Italy); Nicrosini, O.; Piccinini, F. [INFN, Sezione di Pavia (Italy); Riemann, T. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Worek, M. [Bergische Univ., Wuppertal (Germany). Fachbereich Physik

    2011-12-15

    We provide an exact calculation of next-to-next-to-leading order (NNLO) massive corrections to Bhabha scattering in QED, relevant for precision luminosity monitoring at meson factories. Using realistic reference event selections, exact numerical results for leptonic and hadronic corrections are given and compared with the corresponding approximate predictions of the event generator BabaYaga rate at NLO. It is shown that the NNLO massive corrections are necessary for luminosity measurements with per mille precision. At the same time they are found to be well accounted for in the generator at an accuracy level below the one per mille. An update of the total theoretical precision of BabaYaga rate at NLO is presented and possible directions for a further error reduction are sketched. (orig.)

  4. Quantum chemical characterization of N-(2-hydroxybenzylidene)acetohydrazide (HBAH): a detailed vibrational and NLO analysis.

    Science.gov (United States)

    Tamer, Ömer; Avcı, Davut; Atalay, Yusuf

    2014-01-03

    The molecular modeling of N-(2-hydroxybenzylidene)acetohydrazide (HBAH) was carried out using B3LYP, CAMB3LYP and PBE1PBE levels of density functional theory (DFT). The molecular structure of HBAH was solved by means of IR, NMR and UV-vis spectroscopies. In order to find the stable conformers, conformational analysis was performed based on B3LYP level. A detailed vibrational analysis was made on the basis of potential energy distribution (PED). HOMO and LUMO energies were calculated, and the obtained energies displayed that charge transfer occurs in HBAH. NLO analysis indicated that HBAH can be used as an effective NLO material. NBO analysis also proved that charge transfer, conjugative interactions and intramolecular hydrogen bonding interactions occur through HBAH. Additionally, major contributions from molecular orbitals to the electronic transitions were investigated theoretically.

  5. B→ p(ω, φ)η(') Decays and NLO Contributions in pQCD Approach

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-Qing; XIAO Zhen-Jun

    2009-01-01

    By employing the perturbative QCD (pQCD) factorization approach, we calculate some important next-to-leading-order (NLO) contributions to the two-body charmless hadronic decays B+→ p+η(1) and(B0 → p0(ω, φ)η(1)),induced by the vertex QCD corrections, the quark-loops as well as the chromo-magnetic penguins. From the numerical results and phenomenological analysis we find that (a) for B± → p±η(1) (B0 → p0(ω, φ)η(1)) decays, the partial NLO contributions to branching ratios are small (large) in magnitude; and (b) the pQCD predictions for A Cpdir( B±→ p±η(1)) are consistent with the data, while the predicted Acp(B0 p0(ω)η(1)) are generally large in magnitude and could be tested by the forthcoming LHCb experiments.

  6. Parton distribution functions at LO, NLO and NNLO with correlated uncertainties between orders

    CERN Document Server

    :,; Britzger, D; Camarda, S; Cooper-Sarkar, A M; Diaconu, C; Feltesse, J; Gizhko, A; Glazov, A; Kolesnikov, V; Lohwasser, K; Luszczak, A; Myronenko, V; Pirumov, H; Placakyte, R; Rabbertz, K; Radescu, V; Sapronov, A; Schoenig, A; Shushkevich, S; Slominski, W; Starovoitov, P; Sutton, M; Tomaszewska, J; Turkot, O; Watt, G; Wichmann, K; Lisovyi, M

    2014-01-01

    Sets of parton distribution functions (PDFs) of the proton are reported for the leading (LO), next-to-leading (NLO) and next-to-next-to leading order (NNLO) QCD calculations. The parton distribution functions are determined with the HERAFitter program using the data from the HERA experiments and preserving correlations between uncertainties for the LO, NLO and NNLO PDF sets. The sets are used to study cross-section ratios and their uncertainties when calculated at different orders in QCD. A reduction of the overall theoretical uncertainty is observed if correlations between the PDF sets are taken into account for the ratio of $WW$ di-boson to $Z$ boson production cross sections at the LHC.

  7. Photophysical studies of fused phenanthrimidazole derivatives as versatile π-conjugated systems for potential NLO applications.

    Science.gov (United States)

    Jayabharathi, Jayaraman; Thanikachalam, Venugopal; Perumal, Marimuthu Venkatesh

    2012-06-15

    Two new heterocyclic imidazole derivatives consists of π-conjugated system attached to a phenanthrimidazole moiety have been synthesized in moderate yield by the condensation of 1,10-phenanthroline-5,6-dione with substituted aromatic aldehydes and 4-methoxyaniline in the presence of ammonium acetate in ethanol medium. The photophysical properties of these imidazole derivatives were studied in several solvents. These derivatives were evaluated concerning their solvatochromic properties and molecular optical nonlinearities. Their electric dipole moment (μ) and hyperpolarizability (β) have been calculated theoretically and the results indicate that the extension of the π-framework of the ligands has an effect on the NLO properties of these imidazole derivatives. The non-zero tensor components of these imidazole derivatives reveal that they possess potent non-linear optical (NLO) behavior. The energies of the HOMO and LUMO levels and the molecular electrostatic potential (MEP) energy surface studies have exploited the existence of intramolecular charge transfer (ICT) within the molecule.

  8. An Efficient Beam Training Technique for mmWave Communication Under NLoS Channel Conditions

    OpenAIRE

    Yuan, Wenfang; Armour, Simon; Doufexi, Angela

    2016-01-01

    An efficient codebook-based beam training technique is proposed for mmWave communication systems operating under non-line-of-sight (NLoS) channel conditions. Using convex optimization theory, this technique formulates the beam training process as a combinational optimization problem. It finds the best transmit-receive beam pair that maximizes the received signal power by iterating the Nelder-Mead simplex method through a multi-stage formulation of the training process. Compared with beamformi...

  9. MC@NLO for the hadronic decay of Higgs bosons in associated production with vector bosons

    CERN Document Server

    Latunde-Dada, Oluseyi

    2009-01-01

    In this article we describe simulations of the hadronic decay of Higgs bosons produced in association with vector bosons at linear and hadronic colliders. We use the Monte Carlo at next-to-leading-order MC@NLO matching prescription with the Herwig++ event generator to predict various spectra of the resulting b anti-b pairs and compare our results with leading order and matrix element correction predictions.

  10. Evolution of twist-three parton distributions in QCD beyond the large $N_{c}$ limit

    CERN Document Server

    Braun, V M; Manashov, A N

    2000-01-01

    We formulate a consistent 1/N_c^2 expansion of the QCD evolution equations for the twist-three quark distributions g_2(x,Q^2), h_L(x,Q^2) and e(x,Q^2) based on the interpretation of the evolution as a three-particle quantum-mechanical problem with hermitian Hamiltonian. Each distribution amplitude can be decomposed in contributions of partonic components with DGLAP-type scale dependence. We calculate the 1/N_c^2 corrections to the evolution of the dominant component with the lowest anomalous dimension - the only one that survives in the large-N_c limit - and observe a good agreement with the exact numerical results for N_c=3. The 1/N_c^2 admixture of operators with higher anomalous dimensions is shown to be concentrated at a few lowest partonic components and in general is rather weak.

  11. NLO Monte Carlo predictions for heavy-quark production at the LHC. pp collisions in ALICE

    Energy Technology Data Exchange (ETDEWEB)

    Klasen, M.; Kovarik, K.; Topp, M. [Muenster Univ. (Germany). Inst. fuer Theoretische Physik 1; Klein-Boesing, C. [Muenster Univ. (Germany). Inst. fuer Kernphysik; GSI Helmholtzzentrum fuer Schwerionenforschung, Darmstadt (Germany). ExtreMe Matter Institute EMMI; Kramer, G. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Wessels, J.P. [Muenster Univ. (Germany). Inst. fuer Kernphysik

    2014-05-15

    Next-to-leading order (NLO) QCD predictions for the production of heavy quarks in proton-proton collisions are presented within three different approaches to quark mass, resummation and fragmentation effects. In particular, new NLO and parton shower simulations with POWHEG are performed in the ALICE kinematic regime at three different centre-of-mass energies, including scale and parton density variations, in order to establish a reliable baseline for future detailed studies of heavy-quark suppression in heavy-ion collisions. Very good agreement of POWHEG is found with FONLL, in particular for centrally produced D{sup 0}, D{sup +} and D{sup *+} mesons and electrons from charm and bottom quark decays, but also with the generally somewhat higher GM-VFNS predictions within the theoretical uncertainties. The latter are dominated by scale rather than quark mass variations. Parton density uncertainties for charm and bottom quark production are computed here with POWHEG for the first time and shown to be dominant in the forward regime, e.g. for muons coming from heavy-flavour decays. The fragmentation into D{sub s}{sup +} mesons seems to require further tuning within the NLO Monte Carlo approach.

  12. NLO Monte Carlo predictions for heavy-quark production at the LHC: pp collisions in ALICE

    Science.gov (United States)

    Klasen, M.; Klein-Bösing, C.; Kovarik, K.; Kramer, G.; Topp, M.; Wessels, J. P.

    2014-08-01

    Next-to-leading order (NLO) QCD predictions for the production of heavy quarks in proton-proton collisions are presented within three different approaches to quark mass, resummation and fragmentation effects. In particular, new NLO and parton shower simulations with POWHEG are performed in the ALICE kinematic regime at three different centre-of-mass energies, including scale and parton density variations, in order to establish a reliable baseline for future detailed studies of heavy-quark suppression in heavy-ion collisions. Very good agreement of POWHEG is found with FONLL, in particular for centrally produced D 0, D + and D *+ mesons and electrons from charm and bottom quark decays, but also with the generally somewhat higher GM-VFNS predictions within the theoretical uncertainties. The latter are dominated by scale rather than quark mass variations. Parton density uncertainties for charm and bottom quark production are computed here with POWHEG for the first time and shown to be dominant in the forward regime, e.g. for muons coming from heavy-flavour decays. The fragmentation into D s mesons seems to require further tuning within the NLO Monte Carlo approach.

  13. Combining Higher-Order Resummation with Multiple NLO Calculations and Parton Showers in GENEVA

    CERN Document Server

    Alioli, Simone; Berggren, Calvin J; Hornig, Andrew; Tackmann, Frank J; Vermilion, Christopher K; Walsh, Jonathan R; Zuberi, Saba

    2012-01-01

    We extend the lowest-order matching of tree-level matrix elements with parton showers to give a complete description at the next higher perturbative accuracy in alpha_s at both small and large jet resolutions, which has not been achieved so far. This requires the combination of the higher-order resummation of large Sudakov logarithms at small values of the jet resolution variable with the full next-to-leading order (NLO) matrix-element corrections at large values. As a by-product this combination naturally leads to a smooth connection of the NLO calculations for different jet multiplicities. In this paper, we focus on the general construction of our method and discuss its application to e+e and pp collisions. We present first results of the implementation in the GENEVA Monte Carlo framework, where we employ N-jettiness as the jet resolution variable, combining its next-to-next-to-leading logarithmic resummation with fully exclusive NLO matrix elements, and PYTHIA8 as the backend for further parton showering a...

  14. Combining higher-order resummation with multiple NLO calculations and parton showers in GENEVA

    Energy Technology Data Exchange (ETDEWEB)

    Alioli, Simone; Bauer, Christian W.; Berggren, Calvin; Vermilion, Christopher K.; Walsh, Jonathan R.; Zuberi, Saba [California Univ., Berkeley, CA (United States). Ernest Orlando Lawrence Berkeley National Laboratory; Hornig, Andrew [Washington Univ., Seattle, WA (United States). Dept. of Physics; Tackmann, Frank J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Gruppe Theorie

    2012-11-15

    We extend the lowest-order matching of tree-level matrix elements with parton showers to give a complete description at the next higher perturbative accuracy in {alpha}{sub s} at both small and large jet resolutions, which has not been achieved so far. This requires the combination of the higher-order resummation of large Sudakov logarithms at small values of the jet resolution variable with the full next-to-leading order (NLO) matrix-element corrections at large values. As a by-product, this combination naturally leads to a smooth connection of the NLO calculations for different jet multiplicities. In this paper, we focus on the general construction of our method and discuss its application to e{sup +}e{sup -} and pp collisions. We present first results of the implementation in the GENEVA Monte Carlo framework. We employ N-jettiness as the jet resolution variable, combining its next-to-next-to-leading logarithmic resummation with fully exclusive NLO matrix elements, and PYTHIA 8 as the backend for further parton showering and hadronization. For hadronic collisions, we take Drell-Yan production as an example to apply our construction. For e{sup +}e{sup -} {yields} jets, taking {alpha}{sub s}(m{sub Z}) = 0.1135 from fits to LEP thrust data, together with the PYTHIA 8 hadronization model, we obtain good agreement with LEP data for a variety of 2-jet observables.

  15. The chiral S=-1 meson-baryon interaction with new constrains on the NLO contributions

    CERN Document Server

    Ramos, A; Magas, V K

    2016-01-01

    We present a study of the $S=-1$ meson-baryon interaction, employing a chiral SU(3) Lagrangian up to next-to-leading order (NLO) and implementing unitarization in coupled channels. The parameters of the model have been fitted to a large set of experimental scattering data in different two-body channels, to threshold branching ratios, and to the precise SIDDHARTA value of the energy shift and width of kaonic hidrogen. In contrast to other groups, we have taken into consideration the $K^- p\\to K^+\\Xi^-, K^0\\Xi^0$ reaction data, since we found in a previous work to be especially sensitive to the NLO parameters of the chiral Lagrangian. In the present work we also include the Born terms, which usually have very little effect, and find them to be non-negligible in the $K^- p\\to K\\Xi$ channels, correspondingly causing significant modifications to the NLO parameters. We furthermore show that the importance of the Born terms becomes more visible in the isospin projected amplitudes of the $K^-p \\to K\\Xi$ reactions. Th...

  16. NLO QCD corrections to Higgs pair production including dimension-6 operators

    Energy Technology Data Exchange (ETDEWEB)

    Groeber, Ramona [INFN, Sezione di Roma Tre, Roma (Italy); Muehlleitner, Margarete; Streicher, Juraj [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany). Institut fuer Theoretische Physik; Spira, Michael [Paul Scherrer Institut, Villigen (Switzerland)

    2016-07-01

    The role of the Higgs boson has developed from the long-sought particle into a tool for exploring beyond Standard Model (BSM) physics. While the Higgs boson signal strengths are close to the values predicted in the Standard Model (SM), the trilinear Higgs-selfcoupling can still deviate significantly from the SM expectations in some BSM scenarios. The Effective Field Theory (EFT) framework provides a way to describe these deviations in a rather model independent way, by including higher-dimensional operators which modify the Higgs boson couplings and induce novel couplings not present in the SM. The trilinear Higgs-selfcoupling is accessible in Higgs pair production, for which the gluon fusion is the dominant production channel. The next-to-leading (NLO) QCD corrections to this process are important for a proper prediction of the cross section and are known in the limit of heavy top quark masses. In our work, we provide the NLO QCD corrections in the large top quark mass limit to Higgs pair production including dimension-6 operators. The various higher-dimensional contributions are affected differently by the QCD corrections, leading to deviations in the relative NLO QCD corrections of several per-cent, while modifying the cross section by up to an order of magnitude.

  17. The chiral S = -1 meson-baryon interaction with new constraints on the NLO contributions

    Science.gov (United States)

    Ramos, A.; Feijoo, A.; Magas, V. K.

    2016-10-01

    We present a study of the S = - 1 meson-baryon interaction, employing a chiral SU(3) Lagrangian up to next-to-leading order (NLO) and implementing unitarization in coupled channels. The parameters of the model have been fitted to a large set of experimental scattering data in different two-body channels, to threshold branching ratios, and to the precise SIDDHARTA value of the energy shift and width of kaonic hidrogen. In contrast to other groups, we have taken into consideration the K- p →K+Ξ- ,K0Ξ0 reaction data, since we found in a previous work to be especially sensitive to the NLO parameters of the chiral Lagrangian. In the present work we also include the Born terms, which usually have very little effect, and find them to be non-negligible in the K- p → KΞ channels, correspondingly causing significant modifications to the NLO parameters. We furthermore show that the importance of the Born terms becomes more visible in the isospin projected amplitudes of the K- p → KΞ reactions. The measurement of processes that filter single isospin components, like the KL0 p →K+Ξ0 reaction that could be measured at the proposed secondary KL0 beam at Jlab, would put valuable constraints on the chiral models describing the meson-baryon interaction in the S = - 1 sector.

  18. Combining NNPDF3.0 and NNPDF2.3QED through the APFEL evolution code

    CERN Document Server

    Bertone, Valerio

    2016-01-01

    We present sets of parton distribution functions (PDFs), based on the NNPDF3.0 family, which include the photon PDF from the NNPDF2.3QED sets, and leading-order QED contributions to the DGLAP evolution as implemented in the public code APFEL. The aim is to combine our state-of-the-art determination of quark and gluon PDFs with the so far only direct determination of the photon PDF from LHC data. In addition, the use of APFEL allowed us to employ a solution of the DGLAP equation that, differently from that used for the NNPDF2.3QED sets, includes QED corrections in a more accurate way. We briefly discuss how these sets are constructed and investigate the effect of the inclusion of the QED corrections on PDFs and parton luminosities. Finally, we compare the resulting sets, which we dubbed NNPDF3.0QED, to the older NNPDF2.3QED sets and to all presently available PDF sets that include QED corrections, namely CT14QED and MRST2004QED.

  19. In Vivo Non Linear Optical (NLO) Imaging in Live Rabbit Eyes Using the Heidelberg Two-Photon Laser Ophthalmoscope

    Science.gov (United States)

    Hao, Ming; Flynn, Kevin; Nien-Shy, Chyong; Jester, Bryan E.; Winkler, Moritz; Brown, Donald J.; La Schiazza, Olivier; Bille, Josef; Jester, James V.

    2010-01-01

    Imaging of non-linear optical (NLO) signals generated from the eye using ultrafast pulsed lasers has been limited to the study of ex vivo tissues because of the use of conventional microscopes with slow scan speeds. The purpose of this study was to evaluate the ability of a novel, high scan rate ophthalmoscope to generate NLO signals using an attached femtosecond laser. NLO signals were generated and imaged in live, anesthetized albino rabbits using a newly designed Heidelberg Two-Photon Laser Ophthalmoscope with attached 25 mW femtosecond laser having a central wavelength of 780 nm, pulsewidth of 75 fs, and a repetition rate of 50 MHz. To assess two-photon excited fluorescent (TPEF) signal generation, cultured rabbit corneal fibroblasts (RCF) were first labeled by Blue-green fluorescent FluoSpheres (1 μm diameter) and then cells were micro-injected into the central cornea. Clumps of RCF cells could be detected by both reflectance and TPEF imaging at 6 hours after injection. By 6 days, RCF containing fluorescent microspheres confirmed by TPEF showed a more spread morphology and had migrated from the original injection site. Overall, this study demonstrates the potential of using NLO microscopy to sequentially detect TPEF signals from live, intact corneas. We conclude that further refinement of the Two-photon laser Ophthalmoscope should lead to the development of an important, new clinical instrument capable of detecting NLO signals from patient corneas. PMID:20558159

  20. Spin polarisation of t anti tγγ production at NLO+PS with GoSam interfaced to MadGraph5aMC rate at NLO

    Energy Technology Data Exchange (ETDEWEB)

    Deurzen, Hans van; Luisoni, Gionata [Max-Planck-Institut fuer Physik, Munich (Germany); Frederix, Rikkert [Technische Universitaet Muenchen, Physik Department T31, Garching (Germany); Hirschi, Valentin [National Accelerator Laboratory, SLAC, Menlo Park, CA (United States); Mastrolia, Pierpaolo [Max-Planck-Institut fuer Physik, Munich (Germany); Padova Univ. (Italy). Dipt. di Fisica e Astronomia; INFN, Padova (Italy); Ossola, Giovanni [New York City College of Technology, City University of New York, Brooklyn, NY (United States); The Graduate School and University Center, City University of New York, New York, NY (United States)

    2016-04-15

    We present an interface between the multipurpose Monte Carlo tool MadGraph5aMC rate at NLO and the automated amplitude generatorGoSam.As a first application of this novel framework, we compute the NLO corrections to pp → t anti tH and pp → t anti tγγ matched to a parton shower. In the phenomenological analyses of these processes, we focus our attention on observables which are sensitive to the polarisation of the top quarks. (orig.)

  1. arXiv NLO predictions for Higgs boson pair production with full top quark mass dependence matched to parton showers

    CERN Document Server

    Heinrich, G.; Kerner, M.; Luisoni, G.; Vryonidou, E.

    2017-08-21

    We present the first combination of NLO QCD matrix elements for di-Higgs production, retaining the full top quark mass dependence, with a parton shower. Results are provided within both the POWHEG-BOX and MadGraph5_aMC@NLO Monte Carlo frameworks. We assess in detail the theoretical uncertainties and provide differential results. We find that, as expected, the shower effects are relatively large for observables like the transverse momentum of the Higgs boson pair, which are sensitive to extra radiation. However, these shower effects are still much smaller than the differences between the Born-improved HEFT approximation and the full NLO calculation in the tails of the distributions.

  2. Top-antitop pair hadroproduction in association with a heavy boson at the NLO QCD accuracy + Parton Shower

    CERN Document Server

    Garzelli, M V; Papadopoulos, C G; Trocsanyi, Z

    2013-01-01

    The PowHel framework allows to make predictions of total and differential cross-sections of multiparticle hadroproduction processes at both NLO QCD accuracy and NLO QCD matched to Parton Shower, on the basis of the interface between the POWHEG-BOX and HELAC-NLO codes. It has already been applied to study several processes involving a top-antitop pair in association with a third particle or hadronic jet. Our most recent predictions concern top-antitop-V hadroproduction (with V = W or Z), at both parton and hadron level, by considering different decay channels (hadronic and leptonic) of the heavy particles. In particular, we show the results of our phenomenological analyses under the same system of cuts also recently adopted by the CMS collaboration at LHC.

  3. NLO QCD corrections to Single Top and W associated production at the LHC with forward detector acceptances

    CERN Document Server

    Sun, Hao; Hou, Hong-Sheng

    2014-01-01

    In this paper we study the Single Top and W boson associated photoproduction via the main reaction $\\rm pp\\rightarrow p\\gamma p\\rightarrow pW^{\\pm}t+Y$ at the 14 TeV Large Hadron Collider (LHC) up to next-to-leading order (NLO) QCD level assuming a typical LHC multipurpose forward detector. We use the Five-Flavor-Number Schemes (5FNS) with massless bottom quark assumption in the whole calculation. Our results show that the QCD NLO corrections can reduce the scale uncertainty. The typical K-factors are in the range of 1.15 to 1.2 which lead to the QCD NLO corrections of 15$\\%$ to 20$\\%$ correspond to the leading-order (LO) predictions with our chosen parameters.

  4. NLO predictions for Higgs boson pair production with full top quark mass dependence matched to parton showers arXiv

    CERN Document Server

    Heinrich, G.; Kerner, M.; Luisoni, G.; Vryonidou, E.

    We present the first combination of NLO QCD matrix elements for di-Higgs production, retaining the full top quark mass dependence, with a parton shower. Results are provided within both the POWHEG-BOX and MadGraph5_aMC@NLO Monte Carlo frameworks. We assess in detail the theoretical uncertainties and provide differential results. We find that, as expected, the shower effects are relatively large for observables like the transverse momentum of the Higgs boson pair, which are sensitive to extra radiation. However, these shower effects are still much smaller than the differences between the Born-improved HEFT approximation and the full NLO calculation in the tails of the distributions.

  5. NLO corrections and contribution of a tensor gluon operator to the process $\\gamma^{*} \\gamma\\rightarrow \\pi\\pi$

    CERN Document Server

    Kivel, N A; Polyakov, M V

    1999-01-01

    We have calculated the NLO corrections for the leading twist amplitude of the reaction $\\gamma^*\\gamma\\to\\pi\\pi$ at large virtuality of the photon and at $W^2\\ll Q^2$. With a simple model for the two-pion quark and gluon distribution amplitudes we have estimated that the NLO effects may reduce the leading-order amplitude by as much as 30%. We have found that besides the usual twist-2 quark and gluon operators the NLO amplitude receives contribution from a distribution associated with twist-2 tensor gluon operator. The new gluon distribution can be investigated by studying the azimuthal asymmetry of the cross section for $e+\\gamma\\to e'+\\pi\\pi$.

  6. Scaffold characterization using NLO multimodal microscopy in metrology for regenerative medicine

    Science.gov (United States)

    Mortati, Leonardo; Divieto, Carla; Boffitto, Monica; Sartori, Susanna; Ciardelli, Gianluca; Sassi, Maria Paola

    2013-09-01

    Metrology in regenerative medicine aims to develop traceable measurement technologies for characterizing cellular and macromolecule behaviour in regenerative medicine products and processes. One key component in regenerative medicine is using three-dimensional porous scaffolds to guide cells during the regeneration process. The regeneration of specific tissues guided by tissue analogous substrates is dependent on diverse scaffold architectural properties that can be derived quantitatively from scaffolds images. This paper discuss the results obtained with the multimodal NLO microscope recently realized in our laboratory in characterizing 3D tissue engineered (TE) scaffolds colonized from human Mesenchimal stem cells (hMSC), focusing on the study of the three-dimensional metrological parameters.

  7. Full top quark mass dependence in Higgs boson pair production at NLO

    CERN Document Server

    Borowka, S; Heinrich, G; Jones, S P; Kerner, M; Schlenk, J; Zirke, T

    2016-01-01

    We study the effects of the exact top-quark mass dependent two-loop corrections to Higgs boson pair production by gluon fusion at the LHC and at a 100 TeV hadron collider. We perform a detailed comparison of the full next-to-leading order result to various approximations at the level of differential distributions and also analyse non-standard Higgs self-coupling scenarios. We find that the different next-to-leading order approximations differ from the full result by up to 50 percent in relevant differential distributions. This clearly stresses the importance of the full NLO result.

  8. Di-jet production and angular correlations in DIS at NLO

    Directory of Open Access Journals (Sweden)

    Jalilian-Marian Jamal

    2016-01-01

    Full Text Available Angular correlations are a sensitive probe of the dynamics of QCD at high energy. In particular azimuthal angular correlations between two hadrons produced in Deeply Inelastic Scattering (DIS of a virtual photon on a hadron or nucleus offer the best environment in which to investigate high gluon density (gluon saturation effects expected to arise at small x. Here we give a progress report on our derivation of Next to Leading Order (NLO corrections to di-jet (di-hadron production in DIS.

  9. Jet Cross Sections in $\\gamma^{*} \\gamma $ Scattering at $e^{+}e^{-}$ Colliders in NLO QCD

    CERN Document Server

    Pötter, B

    1999-01-01

    Recent results from NLO QCD calculations for inclusive jet cross sections in gamma^*-gamma scattering at e+e- colliders, especially for LEP, are reported. The virtuality Q^2 of the virtual photon is non-zero and can be unlimited large. The virtuality of the second photon is zero and the spectrum is calculated with the Weizs"acker-Williams approximation. Four components of the cross sections have to be distinguished, involving direct and resolved real and virtual photon contributions. Since Q^2 is non-zero, the virtual photon structure function is needed to calculate the contributions involving a resolved virtual photon.

  10. NLO corrections to $\\chi_{bJ}$ two-body exclusive decay processes

    CERN Document Server

    Chen, Long-Bin

    2014-01-01

    The next-to-leading order QCD corrections for $\\chi_{bJ}$, the p-wave bottomonium, to $J/\\psi$ pair decay processes were evaluated utilizing NRQCD factorization formalism. It was determined that the scale dependence was depressed with NLO corrections, and hence the uncertainties in the leading order results were greatly reduced. The total branch ratios were found to be the order of $10^{-5}$ for all three $\\chi_{bJ}\\rightarrow J/\\psi J/\\psi$ processes,indicating that they were observable in the LHC and super-B experiments.

  11. Growth, spectral and thermal studies of an efficient NLO material: Diaquadicinnamatocadmium(II)

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Sunalya M.; Sudarsanakumar, M. R.; Dhanya, V. S. [Department of Chemistry, Mahatma Gandhi College, Thiruvananthapuram 695004, Kerala (India)

    2014-01-28

    A nonlinear metal–organic crystal, diaquadicinnamatocadmium(II) has been grown by controlled gel diffusion technique. Sodium metasilicate was used to prepare the gel. The chemical composition of the crystal has been determined by CHN analysis. Powder X-ray diffraction studies confirm the crystalline nature of the grown crystal. Functional groups present in the compound were identified by FT-IR spectral analysis. The thermal decomposition of the compound was studied using thermogravimetry (TG). The optical transparency range and the lower cut-off wavelength were identified from the UV-Visible-NIR spectrum. The NLO activity of the grown crystal was confirmed using Kurtz and Perry powder test.

  12. APFEL: A PDF Evolution Library with QED corrections

    CERN Document Server

    Bertone, Valerio; Rojo, Juan

    2014-01-01

    Quantum electrodynamics and electroweak corrections are important ingredients for many theoretical predictions at the LHC. This paper documents APFEL, a new PDF evolution package that allows for the first time to perform DGLAP evolution up to NNLO in QCD and to LO in QED, in the variable-flavor-number scheme and with either pole or MSbar heavy quark masses. APFEL consistently accounts for the QED corrections to the evolution of quark and gluon PDFs and for the contribution from the photon PDF in the proton. The coupled QCD+QED equations are solved in x-space by means of higher order interpolation, followed by Runge-Kutta solution of the resulting discretized evolution equations. APFEL is based on an innovative and flexible methodology for the sequential solution of the QCD and QED evolution equations and their combination. In addition to PDF evolution, APFEL provides a module that computes Deep-Inelastic Scattering structure functions in the FONLL general-mass variable-flavor-number scheme up to O($\\alpha_s^2...

  13. NLO QCD off-shell effects for top pair production with a jet in the dilepton channel

    CERN Document Server

    Kraus, Manfred

    2016-01-01

    A short summary of a NLO QCD calculation for the top-quark pair production with a jet in the dilepton decay channel is presented. The calculation takes into account all double, single, non-resonant and interference contributions. Thus, NLO QCD corrections are computed for the process pp -> e+ ve mu- vm~ b b~ j + X. This calculation provides the first complete description, which overcomes the narrow width approximation for ttj process in the dilepton decay channel. Results for the total cross section and differential distributions for the LHC at sqrt(s) = 8 TeV are shown.

  14. NLO properties of formyl-methoxy derivatives of [2.2]paracyclophane containing the donor group in different positions

    Science.gov (United States)

    Puntus, Lada N.; Suponitsky, Kyrill Y.; Antonov, Dmitrii; Pekareva, Irina S.; Lyssenko, Konstantin A.; Kajzar, François

    2014-10-01

    Formyl-methoxy derivatives of [2.2]paracyclophane (pCp) have been synthesized and studied by optical spectroscopy as well as the X-ray diffraction method. These molecules crystallize in acentric space groups. The efficiency of SHG ability of these compounds was measured by the powder technique at 1064 nm fundamental wavelength and average NLO susceptibility for some of them was found comparable with such well-known NLO crystal as NPP. The calculations of molecular and crystalline nonlinearities within density functional theory using M052X/6-31+G* level of approximation were also conducted for the considered series of compounds.

  15. B→πη('), η(')η(') decays and NLO contributions in the pQCD approach

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-Qing; LIU Xin; XIAO Zhen-Jun

    2009-01-01

    By employing the perturbative QCD (pQCD) factorization approach, we calculate the full leading and the partial next-to-leading order (NLO) contributions to the seven B→πη(') and η(')η(') decays. For B+B→π+η(') decays, the pQCD predictions for their decay rates agree very well with the data after the inclusion of the small NLO contributions. For neutral decays, the pQCD predictions are also consistent with the experimental upper limits and can be tested by the LHC experiments. The measured value of ACPdir(π±η)=-19±7% can also be accommodated by the pQCD approach.

  16. {ZZ}\\gamma production in the NLO QCD+EW accuracy at the LHC

    Science.gov (United States)

    Yong, Wang; Ren-You, Zhang; Wen-Gan, Ma; Xiao-Zhou, Li; Shao-Ming, Wang; Huan-Yu, Bi

    2017-08-01

    In this paper we present the first study of the impact of the { O }(α ) electroweak (EW) correction to the {pp}\\to {ZZ}γ +X process at the CERN Large Hadron Collider. The subsequent Z-boson leptonic decays are considered at the leading order using the MadSpin method, which takes into account the spin-correlation and off-shell effects from the Z-boson decays. We provide numerical results of the integrated cross section and the kinematic distributions for this process. In coping with final-state photon-jet separation in the QCD real emission and photon-induced processes, we adopt both the Frixione isolated-photon plus jets algorithm and the phenomenological quark-to-photon fragmentation function method for comparison. We find that the next-to-leading order (NLO) EW correction to the {ZZ}γ production can be sizeable and amounts to about -7 % of the integrated cross section, and provides a non-negligible contribution to the kinematic distributions, particularly in the high energy region. We conclude that the NLO EW correction should be included in precision theoretical predictions in order to match future experimental accuracy.

  17. NLO Monte Carlo predictions for heavy-quark production at the LHC: pp collisions in ALICE

    CERN Document Server

    Klasen, M; Kovarik, K; Kramer, G; Topp, M; Wessels, J

    2014-01-01

    Next-to-leading order (NLO) QCD predictions for the production of heavy quarks in proton-proton collisions are presented within three different approaches to quark mass, resummation and fragmentation effects. In particular, new NLO and parton shower simulations with POWHEG are performed in the ALICE kinematic regime at three different centre-of-mass energies, including scale and parton density variations, in order to establish a reliable baseline for future detailed studies of heavy-quark suppression in heavy-ion collisions. Very good agreement of POWHEG is found with FONLL, in particular for centrally produced D^0, D^+ and D^*+ mesons and electrons from charm and bottom quark decays, but also with the generally somewhat higher GM-VFNS predictions within the theoretical uncertainties. The latter are dominated by scale rather than quark mass variations. Parton density uncertainties for charm and bottom quark production are computed here with POWHEG for the first time and shown to be dominant in the forward reg...

  18. Investigation of nonlinear optical (NLO) properties by charge transfer contributions of amine functionalized tetraphenylethylene

    Science.gov (United States)

    Rana, Meenakshi; Singla, Nidhi; Chatterjee, Amrita; Shukla, Abhishek; Chowdhury, Papia

    2016-12-01

    Nonlinear Optical (NLO) properties of amine functionalized tetraphenylethylene (TPE-NH2) have been recorded and analyzed. The structural geometry, bonding features, harmonic vibrational frequencies (FTIR and Raman) of TPE-NH2 have been investigated by B3LYP density functional theory (DFT). Charge (Mulliken and natural) analysis, natural bond orbital (NBO) analysis, frontier molecular orbitals (FMOs), 13C and 1H nuclear magnetic resonance (NMR) and molecular electrostatic potential (MEP) indicate the delocalization of charges over the donor-acceptor region by the increase of C-N bond length. The vibrational analysis on the basis of potential energy distribution (PED) confirms the charge transfer interaction between donor and acceptor groups, and that in turn validates the presence of the larger dipole moment (μ), polarizability and hyperpolarizabilities (α, β and γ) in TPE-NH2. Higher value of ionization potential (IP), electronegativity (χ), hardness (η), chemical potential (CP) and smaller HOMO-LUMO energy gap (Δε) validate TPE-NH2's strong candidature to be used as an NLO active material.

  19. Comparative studies on molecular structure, vibrational spectra and hyperpolarizabilies of NLO chromophore Ethyl 4-Dimethylaminobenzoate

    Science.gov (United States)

    Amalanathan, M.; Jasmine, G. Femina; Roy, S. Dawn Dharma

    2017-08-01

    The molecular structure, vibrational spectra and polarizabilities of Ethyl 4-Dimethylaminobenzoate (EDAB) was investigated by density functional theory employing Becke's three parameter hybrid exchange functional with Lee-Yang-Parr (B3LYP) co-relational functional involving 6-311++G(d,p) basis set and compared with some other levels. A detailed interpretation of the IR and Raman spectra of EDBA have been reported and analyzed. Complete vibrational assignments of the vibrational modes have been done on the basis of the potential energy distribution (TED) using VEDA software. The molecular electrostatic potential mapped onto total density surface has been obtained. A study on the electronic properties, such as absorption wavelength, and frontier molecular orbitals energy, was performed using DFT approach. The stability of the molecule arising from hyper conjugative interactions and accompanying charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The natural and Mulliken charge also calculated and compared with different level of calculation. The dipole moment, polarizability and first, second order hyperpolarizabilities of the title molecule were calculated and compared with the experimental values. The energy gap between frontier orbitals has been used along with electric moments and first order hyperpolarizability, to understand the non linear optical (NLO) activity of the molecule. The NLO activity of molecule was confirmed by SHG analysis.

  20. Modelling Wt and tWZ production at NLO for ATLAS analyses

    CERN Document Server

    Bessidskaia Bylund, Olga; The ATLAS collaboration

    2016-01-01

    The generation of single top production in the Wt channel at NLO gives rise to doubly-resonant diagrams that overlap with tt, and similarly for associated production with a Z or Higgs boson. Several methods exist to remove this overlap, thus avoiding double counting and separating between the two processes. In Diagram Removal 1, the amplitudes of double-resonant diagrams are set to zero, which also removes the interference of Wt with tt. If a measurement is performed in a region where this interference is not negligible, it would be of interest to take it into account. Another method, Diagram Subtraction, preserves the interference. However, it relies upon momentum reshuffling, which introduces uncertainties to the prediction. An alternative method, Diagram Removal 2, does not involve reshuffling and preserves the interference by subtracting the amplitude squared of the doubly-resonant diagrams from the total. The predictions of Diagram Removal 2 from MG5_aMC@NLO are compared with other predictions for Wt and...

  1. NLO contributions to B{yields}KK{sup *} decays in the pQCD approach

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhi-Qing; Xiao, Zhen-Jun [Nanjing Normal University, Department of Physics and Institute of Theoretical Physics, Nanjing, Jiangsu (China)

    2009-01-15

    We calculate the important next-to-leading-order (NLO) contributions to the B{yields}KK{sup *} decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD (pQCD) factorization approach. The pQCD predictions for the CP-averaged branching ratios are Br(B{sup +}{yields}K{sup +} anti K{sup *0}){approx}3.2 x 10{sup -7},Br(B{sup +}{yields}anti K{sup 0}K{sup *+}){approx}2.1 x 10{sup -7}, Br(B{sup 0}{yields}K{sup 0} anti K{sup *0}+ anti K{sup 0}K{sup *0}){approx}8.5 x 10{sup -7} and Br(B{sup 0}{yields}K{sup +}K{sup *-}+K{sup -}K{sup *+}){approx}1.3 x 10{sup -7}, which agree well with both the experimental upper limits and the predictions based on the QCD factorization approach. Furthermore, the CP violating asymmetries of the considered decay modes are also evaluated. The NLO pQCD predictions for B{sup +}{yields}K{sup +} anti K{sup *0} and K{sup *+} anti K{sup 0} decays are A{sub CP}{sup dir}(K{sup +} anti K{sup *0}){approx}-6.9% and A{sub CP}{sup dir}(K{sup *+} anti K{sup 0}){approx}6.5%. (orig.)

  2. NLO+NLL limits on W' and Z' gauge boson masses in general extensions of the Standard Model

    Science.gov (United States)

    Ježo, Tomáš; Klasen, Michael; Lamprea, David R.; Lyonnet, Florian; Schienbein, Ingo

    2014-12-01

    QCD resummation predictions for the production of charged ( W ') and neutral ( Z ') heavy gauge bosons decaying leptonically are presented. The results of our resummation code at next-to-leading order and next-to-leading logarithmic (NLO+NLL) accuracy are compared to Monte Carlo predictions obtained with PYTHIA at leading order (LO) supplemented with parton showers (PS) and FEWZ at NLO and next-to-next-to-leading order (NNLO) for the p T -differential and total cross sections in the Sequential Standard Model (SSM) and general SU(2)×SU(2)×U(1) models. The LO+PS Monte Carlo and NNLO fixed-order predictions are shown to agree approximately with those at NLO+NLL at small and intermediate p T , respectively, and the importance of resummation for total cross sections is shown to increase with the gauge boson mass. The theoretical uncertainties are estimated by variations of the renormalisation/factorisation scales and of the parton densities, the former being significantly reduced by the resummation procedure. New limits at NLO+NLL on W ' and Z ' boson masses are obtained by reinterpreting the latest ATLAS and CMS results in general extensions of the Standard Model.

  3. NLO QCD Corrections for $J/\\psi+ c + \\bar{c}$ Production in Photon-Photon Collision

    CERN Document Server

    Chen, Zi-Qiang; Qiao, Cong-Feng

    2016-01-01

    The $\\gamma+\\gamma\\rightarrow J/\\psi+c+\\bar{c}$ inclusive process is an extremely important subprocess in $J/\\psi$ photoproduction, like at LEP\\uppercase\\expandafter{\\romannumeral2} or various types future electron-positron colliders. In this work we perform the next-to-leading(NLO) QCD corrections to this process in the framework of non-relativistic QCD(NRQCD) factorization formalism, the first NLO calculation for two projectiles to 3-body quarkonium inclusive production process. By setting the center-of-mass energy at LEP\\uppercase\\expandafter{\\romannumeral2}, the $\\sqrt{s}=197$ GeV, we conduct analyses of the $p_t^2$ distribution and total cross section of this process at the NLO accuracy. It turns out that the total cross section is moderately enhanced by the NLO correction with a $K$ factor of about 1.46, and hence the discrepancy between DELPHI data and color-singlet(CS) calculation is reduced while the color-octet(CO) contributions are still inevitable at this order. At the future Circular Electron-Pos...

  4. Relativistic correction to gluon fragmentation function into pseudoscalar quarkonium

    CERN Document Server

    Gao, Xiangrui; Li, LiuJi; Xiong, Xiaonu

    2016-01-01

    Inspired by the recent measurements of the $\\eta_c$ meson production at LHC, we investigate the relativistic correction effect for the fragmentation function of the gluon into $\\eta_c$, which constitutes the crucial nonperturbative elements to understand $\\eta_c$ production at high $p_T$. Employing three distinct methods, we calculate the leading relativistic correction to the $g\\to\\eta_c$ fragmentation function in the NRQCD factorization framework, as well as verify the existing NLO result for the $c\\to \\eta_c$ fragmentation function. We also study the evolution behavior of these fragmentation functions with the aid of DGLAP equation.

  5. Semi-inclusive jet cross sections within SCET

    CERN Document Server

    Kang, Zhong-Bo; Vitev, Ivan

    2016-01-01

    We review the definition of semi-inclusive jet functions within Soft Collinear Effective Theory (SCET) and their application to inclusive jet cross sections. As an example, we consider both the inclusive production of jets and the jet fragmentation function in proton-proton collisions. The semi-inclusive jet functions satisfy renormalization group (RG) equations which take the form of standard timelike DGLAP evolution equations, analogous to collinear fragmentation functions. By solving these RG equations, the resummation of potentially large single logarithms $(\\alpha_s \\ln R)^n$ can be achieved. We present numerical results at NLO+NLL$_R$ accuracy and compare to existing data from the LHC.

  6. Crystal Growth and Characterization of a New NLO Material: p-Toluidine p-Toluenesulfonate

    Directory of Open Access Journals (Sweden)

    M. Suresh

    2013-01-01

    Full Text Available Single crystals of p-Toluidine p-Toluenesulfonate (PTPT, an organic nonlinear optical (NLO material, have been grown by slow evaporation method at room temperature using ethanol as solvent. The crystal system was confirmed from the single crystal X-ray diffraction analysis. The functional groups were identified using FTIR spectroscopy. UV-Vis-NIR spectrum showed that the UV cut-off wavelength of PTPT occurs at 295 nm and it has insignificant absorption in the wavelength region of 532–800 nm. The SHG efficiency of PTPT was measured by employing Kurtz and Perry powder technique using a Q-switched mode locked Nd: YAG laser emitting 1064 nm for the first time and it was found to be 52% of standard KDP. Thermal and mechanical properties of PTPT were examined by TG/DTA and Vickers microhardness test, respectively.

  7. NLO-QCD corrections to Higgs pair production in the MSSM

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, A.; Degrassi, G. [Dipartimento di Matematica e Fisica, Università di Roma Tre, Via della Vasca Navale 84, I-00146 Rome (Italy); INFN, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146 Rome (Italy); Gröber, R. [INFN, Sezione di Roma Tre, Via della Vasca Navale 84, I-00146 Rome (Italy); Slavich, P. [LPTHE, UPMC University Paris 06, Sorbonne Universités, 4 Place Jussieu, F-75252 Paris (France); LPTHE, CNRS, 4 Place Jussieu, F-75252 Paris (France)

    2016-04-18

    We take a step towards a complete NLO-QCD determination of the production of a pair of Higgs scalars in the MSSM. Exploiting a low-energy theorem that connects the Higgs-gluon interactions to the derivatives of the gluon self-energy, we obtain analytic results for the one- and two-loop squark contributions to Higgs pair production in the limit of vanishing external momenta. We find that the two-loop squark contributions can have non-negligible effects in MSSM scenarios with stop masses below the TeV scale. We also show how our results can be adapted to the case of Higgs pair production in the NMSSM.

  8. ZZ production in gluon fusion at NLO matched to parton-shower

    CERN Document Server

    Alioli, Simone; Luisoni, Gionata; Röntsch, Raul

    2016-01-01

    We present a calculation of the next-to-leading order (NLO) QCD corrections to the hadroproduction process $gg\\to ZZ \\to e^+e^- \\mu^+ \\mu^-$, matched to the parton shower in the POWHEG framework. We take advantage of the POWHEG BOX tool for the implementation and rely on PYTHIA 8 for the showering and hadronization stages. We fully include $\\gamma^*/Z$ interference effects, while also covering the single-resonant region. For this phenomenological study we focus on four lepton production as a signal process, neglecting all quark mass effects as well as the Higgs-mediated contributions, which are known to be subdominant in this case. We provide predictions from our simulations for the 13 TeV LHC Run II setup, including realistic experimental cuts.

  9. Computing decay rates for new physics theories with FEYNRULES and MADGRAPH 5_AMC@NLO

    Science.gov (United States)

    Alwall, Johan; Duhr, Claude; Fuks, Benjamin; Mattelaer, Olivier; Öztürk, Deniz Gizem; Shen, Chia-Hsien

    2015-12-01

    We present new features of the FEYNRULES and MADGRAPH 5_AMC@NLO programs for the automatic computation of decay widths that consistently include channels of arbitrary final-state multiplicity. The implementations are generic enough so that they can be used in the framework of any quantum field theory, possibly including higher-dimensional operators. We extend at the same time the conventions of the Universal FEYNRULES Output (or UFO) format to include decay tables and information on the total widths. We finally provide a set of representative examples of the usage of the new functions of the different codes in the framework of the Standard Model, the Higgs Effective Field Theory, the Strongly Interacting Light Higgs model and the Minimal Supersymmetric Standard Model and compare the results to available literature and programs for validation purposes.

  10. Monitoring molecular orientational order in NLO push-pull based polymeric films via photoacoustic measurements

    Science.gov (United States)

    Torres-Zúñiga, V.; Castañeda-Guzmán, R.; Morales-Saavedra, O. G.; Pérez-Martínez, A. L.; Ogawa, T.

    2011-12-01

    The pulsed-laser photoacoustic-technique (PLPA) was implemented to characterize molecular orientational order and anisotropy in push-pull poled polymeric films as function of temperature and laser polarization. Traditionally, photoacoustic signals are considered to be directly proportional to the linear optical absorption in amorphous media. In this work, however, it is shown that photoacoustic signals can also be highly sensitive to the material anisotropy when convenient polarization dependent photoacoustic analyses are performed. Thus, variation of the molecular orientation in organic films, comprising rod-like polar chromophores, can be unambiguously monitored via rms-analyses performed on the amplitude of the generated opto-acoustical PLPA-signals as function of the incident laser polarization. This result can be useful for the characterization of organic-based nonlinear optical (NLO) poled films and, in general, in studies of anisotropic materials. In fact, in this work we were able to accurately determine the molecular order parameter ( ϕ) of a NLO-active spin-coated polymeric film containing optically active push-pull chromophores. These molecules, previously oriented via an electrical-poling procedure, are capable to exhibit strong second harmonic generation (SHG) effects. The PLPA-measurements were systematically compared to the linear UV-vis optical absorbance spectra while heating the poled film sample in order to monitor the thermally induced molecular disorder, so that the order parameter may be photo-acoustically evaluated via the PLPA-signals generated from the poled to the unpoled film phase. These PLPA-experiments were performed taking into account the UV-vis reference spectra for calibration and comparison purposes in the evaluation of the order parameter. A significant advantage of the PLPA-technique over commonly used optical spectral methodologies is its convenient applicability in samples exhibiting poor or null optical transmission.

  11. Production of D* Mesons with Dijets in Deep-Inelastic Scattering at HERA

    CERN Document Server

    Aktas, A; Anthonis, T; Antunovic, B; Aplin, S; Asmone, A; Astvatsatourov, A; Babaev, A; Backovic, S; Baghdasaryan, A; Baranov, P; Barrelet, E; Bartel, Wulfrin; Baudrand, S; Beckingham, M; Begzsuren, K; Behnke, O; Behrendt, O; Belousov, A; Berger, N; Bizot, J C; Boenig, M O; Boudry, V; Bozovic-Jelisavcic, I; Bracinik, J; Brandt, G; Brinkmann, M; Brisson, V; Bruncko, D; Bunyatyan, A; Buschhorn, G; Bystritskaya, L; Büsser, F W; Campbell, A J; Cantun Avila, K B; Cassol-Brunner, F; Cerny, K; Cerny, V; Chekelian, V; Cholewa, A; Contreras, J G; Coughlan, J A; Cozzika, G; Cvach, J; Dainton, J B; Daum, K; De Boer, Y; De Wolf, E A; Del Degan, M; Delcourt, B; Diaconu, C; Dodonov, V; Dubak, A; Eckerlin, G; Efremenko, V; Egli, S; Eichler, R; Eisele, F; Eliseev, A; Elsen, E; Essenov, S; Falkewicz, A; Faulkner, P J W; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Finke, L; Fleischer, M; Flucke, G; Fomenko, A; Franke, G; Frisson, T; Gabathuler, E; Garutti, E; Gayler, J; Ghazaryan, S; Ginzburgskaya, S; Glazov, A; Glushkov, I; Goettlich, M; Gogitidze, N; Gorbounov, S; Gouzevitch, M; Grab, C; Greenshaw, T; Gregori, M; Grell, B R; Grindhammer, G; Görlich, L; Habib, S; Haidt, D; Hansson, M; Heinzelmann, G; Helebrant, C; Henderson, R C W; Henschel, H; Herrera-Corral, G; Hildebrandt, M; Hiller, K H; Hoffmann, D; Horisberger, Roland Paul; Hovhannisyan, A; Hreus, T; Hussain, S; Jacquet, M; Janssen, X; Jemanov, V; Johnson, D P; Jung, A W; Jung, H; Jönsson, L B; Kapichine, M; Katzy, J; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Klimkovich, T; Kluge, T; Knies, G; Knutsson, A; Korbel, V; Kostka, P; Krastev, K; Kretzschmar, J; Kropivnitskaya, A; Krämer, M; Krüger, K; Landon, M P J; Lange, W; Lastoviicka-Medin, G; Laycock, P; Lebedev, A; Leibenguth, G; Lendermann, V; Levonian, S; Lindfeld, L; Lipka, K; Liptaj, A; List, B; List, J; Loktionova, N; Lubimov, V; Lucaci-Timoce, A I; Lüders, H; Lytkin, L; López-Fernandez, R; Makankine, A; Malinovskii, E I; Marage, P; Marti, L; Martisikova, M; Martyn, H U; Maxfield, S J; Mehta, A; Meier, K; Meyer, A B; Meyer, H; Meyer, J; Michels, V; Mikocki, S; Milcewicz-Mika, I; Mladenov, D; Mohamed, A; Moreau, F; Morozov, A; Morris, J V; Mozer, M U; Murn, P; Müller, K; Nankov, K; Naroska, B; Naumann, T; Newman, P R; Niebuhr, C; Nikiforov, A; Nowak, G; Nowak, K; Nozicka, M; Oganezov, R; Olivier, B; Olsson, J E; Osman, S; Ozerov, D; Palichik, V; Panagoulias, I; Pandurovic, M; Papadopoulou, T; Pascaud, C; Patel, G D; Peng, H; Perez-Astudillo, D; Perieanu, A; Petrukhin, A; Picuric, I; Piec, S; Pitzl, D; Placakyte, R; Povh, B; Prideaux, P; Pérez, E; Rahmat, A J; Raicevic, N; Reimer, P; Rimmer, A; Risler, C; Rizvi, E; Robmann, P; Roland, B; Roosen, R; Rostovtsev, A; Rurikova, Z; Rusakov, S; Salvaire, F; Sankey, D P C; Sauter, M; Sauvan, E; Schmidt, S; Schmitt, S; Schmitz, C; Schoeffel, L; Schultz-Coulon, H C; Schöning, A; Sefkow, F; Shaw-West, R N; Shevyakov, I; Shtarkov, L N; Sloan, T; Smiljanic, I; Smirnov, P; Soloviev, Yu; South, D; Spaskov, V; Specka, A; Steder, M; Stella, B; Stiewe, J; Stoilov, A; Straumann, U; Sunar, D; Sykora, T; Tchoulakov, V; Thompson, G; Thompson, P D; Toll, T; Tomasz, F; Traynor, D; Trinh, T N; Truöl, P; Tsakov, I; Tsipolitis, G; Tsurin, I; Turnau, J; Tzamariudaki, E; Urban, K; Usik, A; Utkin, D; Valkárová, A; Vallée, C; Van Mechelen, P; Vargas-Trevino, A; Vazdik, Ya A; Vinokurova, S; Volchinski, V; Wacker, K; Weber, G; Weber, R; Wegener, D; Werner, C; Wessels, M; Wissing, C; Wolf, R; Wünsch, E; Xella, S M; Yan, W; Yeganov, V; Zaleisak, J; Zhang, Z; Zhelezov, A; Zhokin, A; Zhu, Y C; Zimmermann, J; Zimmermann, T; Zohrabyan, H; Zomer, F; Zácek, J; de Roeck, A

    2007-01-01

    Inclusive D* production is measured in deep-inelastic ep scattering at HERA with the H1 detector. In addition, the production of dijets in events with a D* meson is investigated. The analysis covers values of photon virtuality 2< Q^2 <=100 GeV^2 and of inelasticity 0.05<= y <= 0.7. Differential cross sections are measured as a function of Q^2 and x and of various D* meson and jet observables. Within the experimental and theoretical uncertainties all measured cross sections are found to be adequately described by next-to-leading order (NLO) QCD calculations, based on the photon-gluon fusion process and DGLAP evolution, without the need for an additional resolved component of the photon beyond what is included at NLO. A reasonable description of the data is also achieved by a prediction based on the CCFM evolution of partons involving the k_T-unintegrated gluon distribution of the proton.

  12. Determination of αs at NLO*+NNLL from a global fit of the low-z parton-tohadron fragmentation functions in e+e− and DIS collisions

    Directory of Open Access Journals (Sweden)

    Pérez-Ramos Redamy

    2015-01-01

    Full Text Available The QCD coupling αs is determined from a combined analysis of experimental e+e− and e±p jet data confronted to theoretical predictions of the energy evolution of the parton-to-hadron fragmentation functions (FFs moments –multiplicity, peak, width, skewness– at low fractional hadron momentum z. The impact of approximate next-to-leading order (NLO* corrections plus next-to-next-to-leading log (NNLL resummations, compared to previous LO+NLL calculations, is discussed. A global fit of the full set of existing data, amounting to 360 FF moments at collision energies √s ≈ 1–200 GeV, results in αs(mZ2 = 0.1189−0.0014+0.0025 at the Z mass.

  13. Determination of alpha_s at NLO*+NNLL from a global fit of the low-z parton-to-hadron fragmentation functions in e+e- and DIS collisions

    CERN Document Server

    Pérez-Ramos, Redamy

    2015-01-01

    The QCD coupling alpha_s is determined from a combined analysis of experimental e+e- and e-p jet data confronted to theoretical predictions of the energy evolution of the parton-to-hadron fragmentation functions (FFs) moments --multiplicity, peak, width, skewness-- at low fractional hadron momentum z. The impact of approximate next-to-leading order (NLO*) corrections plus next-to-next-to-leading log (NNLL) resummations, compared to previous LO+NLL calculations, is discussed. A global fit of the full set of existing data, amounting to 360 FF moments at collision energies sqrt(s)~1--200 GeV, results in alpha_s(m_Z^2)=0.1189^{+0.0025}_{-0.0014} at the Z mass.

  14. Quark contribution to the small-x evolution of color dipole

    Energy Technology Data Exchange (ETDEWEB)

    Ian Balitsky

    2006-09-11

    The small-x deep inelastic scattering in the saturation region is governed by the non-linear evolution of Wilson-lines operators. In the leading logarithmic approximation it is given by the BK equation for the evolution of color dipoles. In the NLO the nonlinear equation gets contributions from quark and gluon loops. In this paper I calculate the quark-loop contribution to small-x evolution of Wilson lines in the NLO. It turns out that there are no new operators at the one-loop level--just as at the tree level, the high-energy scattering can be described in terms of Wilson lines. In addition, from the analysis of quark loops I find that the argument of coupling constant in the BK equation is determined by the size of the parent dipole rather than by the size of produced dipoles. These results are to be supported by future calculation of gluon loops.

  15. An NLO QCD analysis of inclusive cross-section and jet-production data from the ZEUS experiment

    CERN Document Server

    Abramowicz, H; Adamczyk, L; Adamus, M; Adler, V; Aghuzumtsyan, G; Allfrey, P D; Antonioli, P; Antonov, A; Arneodo, M; Bailey, D S; Bamberger, A; Barakbaev, A N; Barbagli, G; Barbi, M; Bari, G; Barreiro, F; Bartsch, D; Basile, M; Behrens, U; Bell, M A; Bellagamba, L; Bellan, P M; Benen, A; Bertolin, A; Bhadra, S; Bloch, I; Bold, T; Boos, E G; Borras, K; Boscherini, D; Brock, I; Brook, N H; Brugnera, R; Brümmer, N; Bruni, A; Bruni, G; Bussey, P J; Butterworth, J M; Büttner, C; Bylsma, B; Caldwell, A; Capua, M; Cara Romeo, G; Carli, T; Carlin, R; Cassel, D G; Catterall, C D; Chekanov, S; Chwastowski, J; Ciborowski, J; Ciesielski, R; Cifarelli, Luisa; Cindolo, F; Cole, J E; Collins-Tooth, C; Contin, A; Cooper-Sarkar, A M; Coppola, N; Corradi, M; Corriveau, F; Costa, M; Cottrell, A; Cui, Y; D'Agostini, G; Dal Corso, F; Danilov, P; De Pasquale, S; Dementiev, R K; Derrick, M; Devenish, R C E; Dhawan, S; Dobur, D; Dolgoshein, B A; Doyle, A T; Drews, G; Durkin, L S; Dusini, S; Eisenberg, Y; Ermolov, P F; Eskreys, Andrzej; Everett, A; Ferrando, J; Ferrero, M I; Figiel, J; Foster, B; Foudas, C; Fourletov, S; Fourletova, J; Fry, C; Gabareen, A; Galas, A; Gallo, E; Garfagnini, A; Geiser, A; Genta, C; Gialas, I; Giusti, P; Gladilin, L K; Gladkov, D; Glasman, C; Göbel, F; Goers, S; Goncalo, R; González, O; Gosau, T; Göttlicher, P; Grabowska-Bold, I; Graciani-Díaz, R; Grigorescu, G; Grijpink, S; Groys, M; Grzelak, G; Gutsche, O; Gwenlan, C; Haas, T; Hain, W; Hall-Wilton, R; Hamatsu, R; Hamilton, J; Hanlon, S; Hart, C; Hartmann, H; Hartner, G; Heaphy, E A; Heath, G P; Helbich, M; Hilger, E; Hochman, D; Holm, U; Horn, C; Iacobucci, G; Iga, Y; Irrgang, P; Jakob, H P; Jiménez, M; Jones, T W; Kagawa, S; Kahle, B; Kaji, H; Kananov, S; Karshon, U; Karstens, F; Kasemann, M; Kataoka, M; Katkov, I I; Kcira, D; Keramidas, A; Khein, L A; Kim, J Y; Kind, O; Kisielewska, D; Kitamura, S; Koffeman, E; Kohno, T; Kooijman, P; Koop, T; Korzhavina, I A; Kotanski, A; Kötz, U; Kowal, A M; Kowalski, H; Kramberger, G; Kreisel, A; Krumnack, N; Kulinski, P; Kuze, M; Kuzmin, V A; Labarga, L; Lammers, S; Lelas, D; Levchenko, B B; Levy, A; Li, L; Lightwood, M S; Lim, H; Limentani, S; Ling, T Y; Liu, C; Liu, X; Löhr, B; Lohrmann, E; Loizides, J H; Long, K R; Longhin, A; Lukasik, J; Lukina, O Yu; Luzniak, P; Ma, K J; Maddox, E; Magill, S; Malka, J; Mankel, R; Margotti, A; Marini, G; Martin, J F; Martínez, M; Mastroberardino, A; Matsuzawa, K; Mattingly, M C K; Melzer-Pellmann, I A; Menary, S R; Metlica, F; Meyer, U; Miglioranzi, S; Milite, M; Mirea, A; Monaco, V; Montanari, A; Musgrave, B; Nagano, K; Namsoo, T; Nania, R; Nguyen, C N; Nigro, A; Ning, Y; Noor, U; Notz, D; Nowak, R J; Nuncio-Quiroz, A E; Oh, B Y; Olkiewicz, K; Ota, O; Padhi, S; Palmonari, F; Patel, S; Paul, E; Pavel, Usan; Pawlak, J M; Pelfer, P G; Pellegrino, A; Pesci, A; Piotrzkowski, K; Plamondon, M; Plucinsky, P P; Pokrovskiy, N S; Polini, A; Proskuryakov, A S; Przybycien, M B; Rautenberg, J; Raval, A; Reeder, D D; Ren, Z; Renner, R; Repond, J; Ri, Y D; Rinaldi, L; Robins, S; Rosin, M; Ruspa, M; Ryan, P; Sacchi, R; Salehi, H; Santamarta, R; Sartorelli, G; Savin, A A; Saxon, D H; Schagen, S; Schioppa, M; Schlenstedt, S; Schleper, P; Schmidke, W B; Schneekloth, U; Schörner-Sadenius, T; Sciulli, F; Shcheglova, L M; Skillicorn, I O; Slominski, W; Smith, W H; Soares, M; Solano, A; Son, D; Sosnovtsev, V V; Stairs, D G; Stanco, L; Standage, J; Stifutkin, A; Stonjek, S; Stopa, P; Stösslein, U; Straub, P B; Suchkov, S; Susinno, G; Suszycki, L; Sutiak, J; Sutton, M R; Sztuk, J; Szuba, D; Szuba, J; Tapper, A D; Targett-Adams, C; Tassi, E; Tawara, T; Terron, J; Tiecke, H G; Tokushuku, K; Tsurugai, T; Turcato, M; Tymieniecka, T; Tyszkiewicz, A; Ukleja, A; Ukleja, J; Vázquez, M; Vlasov, N N; Voss, K C; Walczak, R; Walsh, R; Wang, M; Whitmore, J J; Whyte, J; Wichmann, K; Wick, K; Wiggers, L; Wills, H H; Wing, M; Wlasenko, M; Wolf, G; Yagues-Molina, A G; Yamada, S; Yamazaki, Y; Yoshida, R; Youngman, C; Zambrana, M; Zawiejski, L; Zeuner, W; Zhautykov, B O; Zhou, C; Zichichi, A; Ziegler, A; Zotkin, D S; Zotkin, S A; De Favereau, J; De Wolf, E; Del Peso, J

    2005-01-01

    The ZEUS inclusive differential cross-section data from HERA, for charged and neutral current processes taken with e+ and e- beams, together with differential cross-section data on inclusive jet production in e+ p scattering and dijet production in \\gamma p scattering, have been used in a new NLO QCD analysis to extract the parton distribution functions of the proton. The input of jet data constrains the gluon and allows an accurate extraction of \\alpha_s(M_Z) at NLO; \\alpha_s(M_Z) = 0.1183 \\pm 0.0028(exp.) \\pm 0.0008(model) An additional uncertainty from the choice of scales is estimated as \\pm 0.005. This is the first extraction of \\alpha_s(M_Z) from HERA data alone.

  16. NLO NRQCD disfavors the interpretation of X(3872) as {chi}{sub c1}(2P)

    Energy Technology Data Exchange (ETDEWEB)

    Butenschoen, Mathias [Wien Univ. (Austria). Fakultaet fuer Physik; He, Zhi-Guo; Kniehl, Bernd A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2013-03-15

    We study {chi}{sub c1}(2P) inclusive hadroproduction at next-to-leading order (NLO) within the factorization formalism of nonrelativistic quantum chromodynamics (NRQCD), including both the color-singlet {sup 3}P{sub 1}{sup [1]} and color-octet {sup 3}S{sub 1}{sup [8]} c anti c Fock states. Assuming the recently discovered X(3872) hadron to be the 2P (1{sup ++}) charmonium state, we perform a fit to the cross sections measured by the CDF, CMS, and LHCb Collaborations. We either obtain an unacceptably high value of {chi}{sup 2} or a value of vertical stroke R{sub 2P}{sup '}(0) vertical stroke incompatible with well-established potential models. We thus conclude that NLO NRQCD is incompatible with the hypothesis X(3872){identical_to}{chi}{sub c1}(2P).

  17. Second harmonic generation in NLO polymers excited by Surface Plasmon enhanced electric field induced by femtosecond optical pulses

    Directory of Open Access Journals (Sweden)

    Kawata Y.

    2013-03-01

    Full Text Available We will report second harmonic generation (SHG in nonlinear optical (NLO polymers excited by surface plasmon enhanced optical fields. The surface plasmon (SP polariton was excited in an attenuated total reflection geometry having the Kretchmann configuration. The NLO polymers, consisting of Disperse Red1 as guest chromophores and poly (methyl methacrylate as host materials, were coated upon the Ag layers. Our experimental results indicated that the SHG signal intensity from the polymer coated Ag films was more than 10 times higher than that from the non-coated Ag films. The SHG autocorrelation traces excited by SP-enhanced fields were also studied and the correlation time was shorter than 150 fs, the temporal resolutions of the present spectrometer.

  18. Combining Higher-Order Resummation with Multiple NLO Calculations and Parton Showers in the GENEVA Monte Carlo Framework

    CERN Document Server

    Alioli, Simone; Berggren, Calvin; Hornig, Andrew; Tackmann, Frank J; Vermilion, Christopher K; Walsh, Jonathan R; Zuberi, Saba

    2013-01-01

    We discuss the GENEVA Monte Carlo framework, which combines higher-order resummation (NNLL) of large Sudakov logarithms with multiple next-to-leading-order (NLO) matrix-element corrections and parton showering (using PYTHIA8) to give a complete description at the next higher perturbative accuracy in alpha_s at both small and large jet resolution scales. Results for e+e- -> jets compared to LEP data and for Drell-Yan production are presented.

  19. Drell-Yan, ZZ, W+W- production in SM & ADD model to NLO+PS accuracy at the LHC

    CERN Document Server

    Frederix, R; Mathews, P; Ravindran, V; Seth, S

    2014-01-01

    In this paper, we present the next-to-leading order QCD corrections for di-lepton, di-electroweak boson (ZZ, W+W-) production in both the SM and the ADD model, matched to the HERWIG parton-shower using the aMC@NLO framework. A selection of results at the 8 TeV LHC, which exhibits deviation from the SM as a result of the large extra-dimension scenario are presented.

  20. NLO+NLL limits on W' and Z' gauge boson masses in general extensions of the Standard Model

    CERN Document Server

    Jezo, T; Lamprea, D R; Lyonnet, F; Schienbein, I

    2014-01-01

    QCD resummation predictions for the production of charged (W') and neutral (Z') heavy gauge bosons decaying leptonically are presented. The results of our resummation code at next-to-leading order and next-to-leading logarithmic (NLO+NLL) accuracy are compared to Monte Carlo predictions obtained with PYTHIA at leading order (LO) supplemented with parton showers (PS) and FEWZ at NLO and next-to-next-to-leading order (NNLO) for the $p_T$-differential and total cross sections in the Sequential Standard Model (SSM) and general SU(2)xSU(2)xU(1) models. The LO+PS Monte Carlo and NNLO fixed-order predictions are shown to agree approximately with those at NLO+NLL at small and intermediate $p_T$, respectively, and the importance of resummation for total cross sections is shown to increase with the gauge boson mass. The theoretical uncertainties are estimated by variations of the renormalisation/factorisation scales and of the parton densities, the former being significantly reduced by the resummation procedure. New li...

  1. Correlation between structural studies and third order NLO properties of selected new quinolinium semi-organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Bouchouit, K., E-mail: karim.bouchouit@laposte.net [Departement de Chimie, Faculte des Sciences, Universite de Jijel (Algeria); Bendeif, E.E. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisation CRM2 CNRS UMR 7036, Institut Jean Barriol, Nancy Universite, Faculte des Sciences, BP 239, 54506 Vandoeuvre-les-Nancy, CEDEX (France); EL Ouazzani, H. [Institut des Sciences et Technologies Moleculaires d' Angers UMR CNRS 6200 MOLTECH ANJOU, Universite d' Angers 2, Boulevard Lavoisier, 49045 Angers (France); Dahaoui, S.; Lecomte, C. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisation CRM2 CNRS UMR 7036, Institut Jean Barriol, Nancy Universite, Faculte des Sciences, BP 239, 54506 Vandoeuvre-les-Nancy, CEDEX (France); Benali-cherif, N. [Laboratoire des Structures, Proprietes et Interactions Inter Atomiques (LASPI2A), Centre Universitaire de Khenchela, 40000 Khenchela (Algeria); Sahraoui, B. [Institut des Sciences et Technologies Moleculaires d' Angers UMR CNRS 6200 MOLTECH ANJOU, Universite d' Angers 2, Boulevard Lavoisier, 49045 Angers (France)

    2010-09-14

    Graphical abstract: Organic quinolinium moieties build a zigzag layers in compounds (II) - Abstract: New quinolinium semi-organic compounds of formula (C{sub 9}H{sub 8}N){sub 2}{sup +}.SO{sub 4}{sup 2-},H{sub 2}O (I) (bis-quinolinium sulphate monohydrate) and (C{sub 9}H{sub 8}N){sup +}.NO{sub 3}{sup -} (II) (quinolinium nitrate) have been synthesized and characterized by UV-Vis absorption spectroscopy, nonlinear optical (NLO) measurements and by single crystal X-ray diffraction. The third order nonlinear optical properties of (I) and (II) were investigated using two methods: the degenerate four wave mixing technique (DFWM) performed in solution at {lambda} = 532 nm and the third-harmonic generation (THG) measurements carried out on thin films at {lambda} = 1064 nm. The NLO measurements showed that compound (I) presents better nonlinear optical properties compared to compound (II). To understand further the optical behaviour of (I) and (II), the crystal structures of both compounds were determined from accurate single crystal X-ray diffraction measurements performed at 100 K. The crystallographic studies revealed the key role of the intermolecular interactions and the molecular arrangements in the enhancement of the NLO properties.

  2. Effect of chromophore-chromophore electrostatic interactions in the NLO response of functionalized organic-inorganic sol-gel materials

    Science.gov (United States)

    Reyes-Esqueda, J.; Darracq, B.; García-Macedo, J.; Canva, M.; Blanchard-Desce, M.; Chaput, F.; Lahlil, K.; Boilot, J. P.; Brun, A.; Lévy, Y.

    2001-10-01

    In the last years, important non-linear optical (NLO) results on sol-gel and polymeric materials have been reported, with values comparable to those found in crystals. These new materials contain push-pull chromophores either incorporated as guest in a high Tg polymeric matrix (doped polymers) or grafted onto the polymeric matrix. These systems present several advantages, however they require significant improvement at the molecular level—by designing optimized chromophores with very large molecular figure of merit, specific to each application targeted. Besides, it was recently stated in polymers that the chromophore-chromophore electrostatic interactions, which are dependent of chromophore concentration, have a strong effect into their NLO properties. This has not been explored at all in sol-gel systems. In this work, the sol-gel route was used to prepare hybrid organic-inorganic thin films with different NLO chromophores grafted into the skeleton matrix. Combining a molecular engineering strategy for getting a larger molecular figure of merit and by controlling the intermolecular dipole-dipole interactions through both: the tuning of the push-pull chromophore concentration and the control of tetraethoxysilane concentration, we have obtained a r33 coefficient around 15 pm/V at 633 nm for the classical DR1 azo-chromophore and a r33 around 50 pm/V at 831 nm for a new optimized chromophore structure.

  3. Higgs production in association with off-shell top-antitop pairs at NLO EW and QCD at the LHC

    Science.gov (United States)

    Denner, Ansgar; Lang, Jean-Nicolas; Pellen, Mathieu; Uccirati, Sandro

    2017-02-01

    We present NLO electroweak corrections to Higgs production in association with off-shell top-antitop quark pairs. The full process ppto {e}+{ν}e{μ}-{overline{ν}}_{μ}boverline{b}H is considered, and hence all interference, off-shell, and non-resonant contributions are taken into account. The electroweak corrections turn out to be below one per cent for the integrated cross section but can exceed 10% in certain phase-space regions. In addition to its phenomenological relevance, the computation constitutes a major technical achievement as the full NLO virtual corrections involving up to 9-point functions have been computed exactly. The results of the full computation are supported by two calculations in the double-pole approximation. These also allow to infer the effect of off-shell contributions and emphasise their importance especially for the run II of the LHC. Finally, we present combined predictions featuring both NLO electroweak and QCD corrections in a common set-up that will help the experimental collaborations in their quest of precisely measuring the aforementioned process.

  4. Diphoton production at Tevatron and the LHC in the NLO$^\\star$ approximation of the Parton Reggeization Approach

    CERN Document Server

    Nefedov, Maxim

    2015-01-01

    The hadroproduction of prompt isolated diphotons at high energies is studied in the NLO^star framework of the Parton Reggeization Approach. The real part of the NLO corrections is computed, and the procedure for the subtraction of double counting between real parton emissions in the hard-scattering matrix element and unintegrated PDF is constructed for the amplitudes with Reggeized quarks in the initial state. The matrix element of the important NNLO subprocess RR->2gamma with full dependence on the transverse momenta of the initial-state partons is obtained. We compare obtained numerical results with diphoton spectra measured at Tevatron and the LHC, and find a good agreement of our predictions with experimental data at the high values of diphoton transverse momentum, p_T, and especially at the p_T larger than the diphoton invariant mass, M. In this multi-Regge kinematics region, the NLO correction is strongly suppressed, demonstrating the self-consistency of the Parton Reggeization Approach.

  5. Growth and characterization of NLO crystal: L-leucine phthalic acid potassium iodide

    Directory of Open Access Journals (Sweden)

    Jagadeesh M.R.

    2015-09-01

    Full Text Available A new semi-organic non linear optical crystal, L-leucine phthalic acid potassium iodide (LLPPI has been grown from an aqueous solution by slow evaporation method. The grown crystals were subjected to different characterizations, such as single crystal XRD, FT-IR, UV-Vis, TGA, SEM, EDAX, micro hardness, dielectric and powder SHG. Single crystal structure was determined from X-ray diffraction data and it revealed that the crystal belongs to triclinic system with the space group P1. The vibrational frequencies of various functional groups were derived from FT-IR spectrum. Thermal stability of the grown crystal was investigated by TG-DTA studies and it was observed that the crystal was thermally stable up to 192 °C. Optical absorption study was carried out and a good transparency in the entire visible region was observed at the lower cutoff wavelength of 227 nm. Dielectric study was performed as a function of frequency and normal dielectric behavior was observed. The micro hardness test was carried out and the load dependent hardness was measured. Kurtz powder method was employed to explore the NLO characteristics of the grown crystal.

  6. Constraints on the S=-1 meson-baryon interaction at NLO

    Science.gov (United States)

    Feijoo, A.; Magas, V. K.; Ramos, A.

    2017-03-01

    This work contains a study of the meson-baryon interaction in the S = -1 sector by means of a chiral SU(3) Lagrangian up to next-to-leading order (NLO) and implementing unitarization in coupled channels. In order to get more reliable values of the parameters which are present in the model, we performed several fits which take a large set of experimental scattering data in different two-body channels, threshold branching ratios, and the precise SIDDHARTA values of the energy shift and width of kaonic hidrogen into consideration. In previous studies, we had shown that the K- p → KΞ reactions are especially sensitive to the next to Weinberg-Tomozawa (WT) corrections in the hierarchy. In addition, we pointed out the need to employ processes which are described by pure isospin amplitudes as a tool to discern which models are more realistic among those which give small values for the χ2 in the fits. Following the former suggestion, we present results which include data from K- p → ηΛ, ηΣ reactions which have pure isospin I = 0 and I = 1 component respectively. Finally, to check the goodness of the new obtained parametrization of the model, we present a prediction for another process that filters the I = 1 isospin component: the pure I = 1 K_L^ - p \\to {K^ + }{Ξ^0} reaction which could be measured at the proposed secondary K0L beam at Jlab.

  7. Complete NLO QCD Corrections for Tree Level Delta F = 2 FCNC Processe

    CERN Document Server

    Buras, Andrzej J

    2012-01-01

    Anticipating the important role of tree level FCNC processes in the indirect search for new physics at distance scales as short as 10^-19-10^-21 m, we present complete NLO QCD corrections to tree level Delta F=2 processes mediated by heavy colourless gauge bosons and scalars. Such contributions can be present at the fundamental level when GIM mechanism is absent as in numerous Z' models, gauged flavour models with new heavy neutral gauge bosons and Left-Right symmetric models with heavy neutral scalars. They can also be generated at one loop in models having GIM at the fundamental level and MFV of which Two-Higgs Doublet models with and without SUSY are the best known examples. In models containing vectorial heavy fermions that mix with the standard chiral quarks and models in which Z and SM neutral Higgs H mix with new heavy gauge bosons and scalars also tree-level Z and SM neutral Higgs contributions to Delta F=2 processes are possible. In all these extensions new local operators are generated having Wilson...

  8. Quantifying jet transport properties via large $p_T$ hadron productions at NLO

    CERN Document Server

    Liu, Zhi-Quan; Zhang, Ben-Wei; Wang, Enke

    2015-01-01

    Nuclear modification factor $R_{AA}$ for large $p_T$ single hadron is studied in a next-to-leading order (NLO) perturbative QCD (pQCD) parton model with medium-modified fragmentation functions (mFFs) due to jet quenching in high-energy heavy-ion collisions. The energy loss of the hard partons in the QGP is incorporated in the mFFs which utilize two most important parameters to characterize the transport properties of the hard parton jets: the jet transport parameter $\\hat q_{0}$ and the mean free path $\\lambda_{0}$, both at the initial time $\\tau_0$. A phenomenological study of the experimental data for $R_{AA}(p_{T})$ is performed to constrain the two parameters with simultaneous $\\chi^2/{\\rm d.o.f}$ fits to RHIC as well as LHC data. We obtain for energetic quarks $\\hat q_{0}\\approx 1.1 \\pm 0.2$ GeV$^2$/fm and $\\lambda_{0}\\approx 0.4 \\pm 0.03$ fm in central $Au+Au$ collisions at $\\sqrt{s_{NN}}=200$ GeV, while $\\hat q_{0}\\approx 1.7 \\pm 0.3$ GeV$^2$/fm, and $\\lambda_{0}\\approx 0.5 \\pm 0.05$ fm in central $Pb+...

  9. Advanced Software Ground Station and UAV Development for NLoS Control Using Mobile Communications

    Directory of Open Access Journals (Sweden)

    Amr AbdElHamid

    2015-01-01

    Full Text Available Over the last decades, Unmanned Aerial Systems (UASs have gained much attention due to their various applications in different sections. However, their communication range is limited to utilized communication equipment. Therefore, utilization of GSM channels opens a new prospect towards long distance UAV missions and mobile command and control centers. This paper demonstrates new design and development of a small-scale UAV and a Ground Control Station (GCS using GSM bidirectional communications for Non-Line of Sight (NLoS long range control. GCSs are considered the front end node in UAV guidance process. Therefore, the proposed GCS employs a two-layer framework to consider all ground pilot requirements. Moreover, a new exploitation of global weather forecast data is added to the GCS. On the other hand, the proposed airborne system utilizes a new integration of different Commercial off-the-Shelf (COTS components and excludes short range receivers. The ground and flight tests show that stable bidirectional GSM communication is established, reliable hardware integration is accomplished, real time performance is achieved, GCS functional fidelity is obtained, and low cost is maintained. Finally, some qualitative aspects of the proposed platform are presented to address the detailed features.

  10. Growth and structural analysis of an organic NLO compound: L-lysinium picrate

    Science.gov (United States)

    Arthi, D.; Ilango, E.; Mercina, M.; Jayaraman, D.; Joseph, V.

    2017-01-01

    L-lysinium picrate (LLP), an organic material, has been synthesized and grown by solution growth method. The crystal structure of the grown material was solved by single crystal X-ray diffraction analysis and it was found that the material belongs to triclinic system with space group P1. The transmission range of the crystal was measured in the range of 470-1100 nm with lower cut off wavelength at 470 nm using UV-vis-NIR absorption spectrum. The optical band gap of the grown material was found to establish the dielectric behavior of the material. The main functional groups present in the material were identified using FTIR spectral analysis. Thermal stability and decomposition range were studied by means of TGA and DTA analyses. The microstructure of the grown crystal was studied using SEM analysis. The various chemical environments of the protons and carbons were studied by 1H and 13C NMR spectroscopy to confirm the molecular structure of the grown crystal. NLO behavior was confirmed by Kurtz and Perry technique and SHG efficiency was estimated as 1.4 times that of standard KDP.

  11. The exclusive J/ψ process at the LHC tamed to probe the low x gluon

    Energy Technology Data Exchange (ETDEWEB)

    Jones, S.P. [Max-Planck-Institute for Physics, Munich (Germany); Martin, A.D. [Institute for Particle Physics Phenomenology Durham University, Durham (United Kingdom); Ryskin, M.G. [Institute for Particle Physics Phenomenology Durham University, Durham (United Kingdom); Petersburg Nuclear Physics Institute, NRC Kurchatov Institute, St. Petersburg (Russian Federation); Teubner, T. [University of Liverpool, Department of Mathematical Sciences, Liverpool (United Kingdom)

    2016-11-15

    The perturbative QCD expansion for J/ψ photoproduction appears to be unstable: the NLO correction is large (and of opposite sign) to the LO contribution. Moreover, the predictions are very sensitive to the choice of factorisation and renormalisation scales. Here we show that perturbative stability is greatly improved by imposing a 'Q{sub 0} cut' on the NLO coefficient functions; a cut which is required to avoid double counting. Q{sub 0} is the input scale used in the parton DGLAP evolution. This result opens the possibility of high precision exclusive J/ψ data in the forward direction at the LHC being able to determine the low x gluon distribution at low scales. (orig.)

  12. The $NLO$ production of the $W^{\\pm}$ and $Z^0$ vector bosons via hadron collisions in the frameworks of $KMR$ and $MRW$ unintegrated parton distribution functions

    CERN Document Server

    Modarres, M; Aminzadeh-Nik, R; Hosseinkhani, H; Olanj, N

    2016-01-01

    In a series of papers, we have investigated the compatibility of the $Kimber$-$Martin$-$Ryskin$ ($KMR$) and $Martin$-$Ryskin$-$Watt$ ($MRW$) $unintegrated$ parton distribution functions ($UPDF$) as well as the description of the experimental data on the proton structure functions. The present work is a sequel to that survey, via calculation of the transverse momentum distribution of the electro-weak gauge vector bosons in the $k_t$-factorization scheme, by the means of the $KMR$, the $LO\\;MRW$ and the $NLO\\;MRW$ $UPDF$, in the next-to leading order ($NLO$). To this end, we have calculated and aggregated the invariant amplitudes of the corresponding $involved$ diagrams in the $NLO$, and counted the individual contributions in different frameworks. The preparation process for the $UPDF$ utilizes the $PDF$ of $Martin$ et al, $MSTW2008-LO$, $MSTW2008-NLO$, $MMHT2014-LO$ and $MMHT2014-NLO$ as the inputs. Afterwards, the results have been analyzed against each other, as well as the existing experimental data. Our c...

  13. Applicability of the Wigner functional approach to evolution of quantum fields

    Directory of Open Access Journals (Sweden)

    Leonidov Andrey

    2016-01-01

    Full Text Available Evolution of highly excited quantum field is considered in the framework of Keldysh formalism . It is demonstrated that leading order (LO term of semiclassical approximation appears as well-known Classical Statistical Approximation (CSA. In simple case of spatially homogeneous scalar field analytical expressions for leading and next-to-leading (NLO order are presented. It is shown that the range of applicability of CSA strongly depends on the properties of the initial state of the system.

  14. η meson production of high-energy nuclear collisions at NLO

    Directory of Open Access Journals (Sweden)

    Wei Dai

    2015-11-01

    Full Text Available The transverse momentum spectrum of η meson in relativistic heavy-ion collisions is studied at the Next-to-Leading Order (NLO within the perturbative QCD, where the jet quenching effect in the QGP is incorporated with the effectively medium-modified η fragmentation functions using the higher-twist approach. We show that the theoretical simulations could give nice descriptions of PHENIX data on η meson in both p+p and central Au + Au collisions at the RHIC, and also provide numerical predictions of η spectra in central Pb + Pb collisions with sNN=2.76 TeV at the LHC. The ratios of η/π0 in p+p and in central Au + Au collisions at 200 GeV are found to overlap in a wide pT region, which matches well the measured ratio η/π0 by PHENIX. We demonstrate that, at the asymptotic region when pT→∞ the ratios of η/π0 in both Au + Au and p+p are almost determined only by quark jets fragmentation and thus approach to the one in e+e− scattering; in addition, the almost identical gluon (quark contribution fractions to η and to π result in a rather moderate variation of η/π0 distribution at intermediate and high pT region in A+A relative to that in p+p; while a slightly higher η/π0 at small pT in Au + Au can be observed due to larger suppression of gluon contribution fraction to π0 as compared to the one to η. The theoretical prediction for η/π0 at the LHC has also been presented.

  15. Synthesis, structure, thermal and NLO characterization of 4-hydroxy tetramethylpiperazinium picrate crystals

    Indian Academy of Sciences (India)

    T Dhanabal; G Amirthaganesan; M Dhandapani; Samar K Das

    2012-07-01

    Good quality single crystals of 4-hydroxy tetramethylpiperazinium picrate (TMPP) were grown by slow evaporation solution growth method at room temperature. The average dimensions of the grown crystals were 0.6 × 0.2 × 0.2 cm3. The solubility of the compound was estimated using methanol and acetone. The elemental analysis confirms the formation of the compound in the stoichiometric proportion. The UV-visible transmittance study indicates that the crystal possesses minimum transmittance at 370 nm and no absorption at 470-900 nm. The Bragg peaks obtained in the powder X-ray diffraction pattern confirm its crystallinity. The thermal behaviour of the crystal was investigated using thermogravimetric (TG) and differential thermal analysis (DTA) techniques. The structure of the compound was determined by using single crystal X-ray diffraction method. The compound was found to be crystallize in the monoclinic space group P2(1)/c (a = 6.9513(8)Å, b = 11.8016(14)Å, c = 22.018(2)Å, = 90.00°, = 92.575(2)°, = 90.00°). The thermal anomalies observed in the differential scanning calorimetry (DSC) heating and cooling cycles indicate the occurrence of first order phase transition. Fourier transform infrared (FTIR) and polarized Raman spectral analyses were used to confirm the presence of various functional groups in the compound. The nonlinear optical property (NLO) of the crystal was analysed by Kurtz-Perry powder technique and found that the compound has SHG efficiency 1.5 times greater that of potassium dihydrogen phosphate (KDP).

  16. Synthesis and characterization of polymers and interpenetrating polymer networks (IPNs) with nonlinear optical (NLO) properties and related numerical studies

    Science.gov (United States)

    Sharma, P. R. Srikanth

    Copolymers of methyl methacrylate (MMA) and 2-propenoic acid, 2-methyl-, 2-[[[[4-methyl-3-[[[2-methyl-4-nitrophenyl)amino]carbonyl]aminophenyl]carbonyl]oxy]ethyl ester (PAMEE) exhibiting nonlinear optical (NLO) properties have been synthesized. Two kinds of urethane containing interpenetrating polymer networks (IPNs), consisting of nonlinear optical (NLO) chromophore, 2-methyl-4-nitroaniline (MNA) or Disperse Red1 (DR1) have been synthesized. The IPN systems consist of either aliphatic polycarbonate urethane (PCU) or 2,6-dimethyl-1,4-phenylene oxide (PPO) as one network and crosslinked poly (MMA-co-PAMEE) or poly (MMA-co-PMNEE) as the second network. Copolymers and interpenetrating polymer networks (IPNs) were characterized by IR spectroscopy, UV-VIS spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and second harmonic generation (SHG) measurements. The thin films of copolymers and IPNs were optically transparent and the corona poled polymers produced relatively large and stable SHG signals at room temperature. To understand the polarization decay of our NLO polymer we studied a simple theoretical model which can account for the main features which we observe. The addition of an apparent "chemical" reaction with a reaction activation energy EAB to the neighbor-facilitated Fredrickson-Anderson model shows the existence of a beta relaxation occurring simultaneously with the main alpha process. The combination of an Ising-model with antiferromagnetic interaction and the neighbor-facilitated Fredrickson-Anderson model allows a description of the polarization decay of polarized materials, such as our polymers, below the glass transition temperature Tg. The relaxation time for the polarization scales with the relaxation time of the alpha-process of the glass transition, and shows a typical curvature in the ln tau versus T-1 plot. Real polymers, such as poly(MMA-co-PAMEE) which we study possess both of these features and its

  17. Determination of the fragmentation functions from an NLO QCD analysis of the HERMES data on pion multiplicities

    Science.gov (United States)

    Leader, Elliot; Sidorov, Alexander V.; Stamenov, Dimiter B.

    2016-04-01

    An NLO QCD analysis of the final HERMES data on pion multiplicities is presented and a new set of pion fragmentation functions is extracted from the best fit to the data. We have studied the so-called [x ,z ] and [Q2,z ] presentations of their data, as given by HERMES, which, in principle, should simply be two different ways of presenting the experimental data. We have based our extraction on an excellent fit to the [Q2,z ] presentation of the data.

  18. Determination of the fragmentation functions from an NLO QCD analysis of the HERMES data on pion multiplicities

    CERN Document Server

    Leader, Elliot; Stamenov, Dimiter B

    2015-01-01

    An NLO QCD analysis of the final HERMES data on pion multiplicities is presented and a new set of pion fragmentation functions is extracted from the best fit to the data. We have studied the so-called $[x,z]$ and $[Q^2,z]$ presentations of the HERMES data which, in principle, should simply be two different ways of presenting the same data. As we explain in detail, it appears that there is an inconsistency between these two formats and our extraction is based on the $[Q^2,z]$ presentation of the data.

  19. Synthesis and NLO Properties of Chromophores with 1,8-Dimethoxy-9,10-dihydroanthracene and Thiobarbituric acid Moieties

    Institute of Scientific and Technical Information of China (English)

    WU De-Lin; JIA Zhao-Li; SHI Jie-Ping; SHI Zheng-Wei; LU Guo-Yuan

    2008-01-01

    The new chromophore molecules with nonlinear optical (NLO) properties were prepared by Knoevenagel condensation from 4,5-diformyl-1,8-dimethoxy-9,10-dihydroanthracene and thiobarbituric acid derivatives in the presence of piperidine and acetic acid. In these chromophores, the ring-locked triene employed as a conjugation bridge and the thiobarbituric acid moiety was as an electron acceptor in a D-π-A units. The solvatochromism and UV spectra indicate that they have higher second-order nonlinear polarizability μβ values than the corresponding reference compound, without causing a large red shift of the charge transfer band.

  20. Transverse Single Spin Asymmetry in $e+p^\\uparrow \\to e+J/\\psi +X $ and $Q^2$ -evolution of Sivers Function-II

    CERN Document Server

    Godbole, Rohini M; Misra, Anuradha; Rawoot, Vaibhav S

    2014-01-01

    We present estimates of Single Spin Asymmetry(SSA) in the electroproduction of J/{\\psi} taking into account the transverse momentum dependent(TMD) evolution of the Sivers function. We estimate SSA for JLab, HERMES, COMPASS and eRHIC energies using color evaporation model of J/{\\psi}. We have calculated the asymmetry using recent parameters extracted by Echevarria et al. using the CSS approach to TMD evolution. These recent TMD evolution fits are based on the evolution kernel in which the perturbative part is resummed up to NLL accuracy. We have also estimated the asymmetry by using parameters which had been obtained by a fit by Anselmino et al., using both an exact numerical and an approximate analytical solution of the TMD evolution equations. We find that the variation among the different estimates obtained using TMD evolution is much smaller than between these on one hand and the estimates obtained using DGLAP evolution on the other. Even though the use of TMD evolution causes an overall reduction in asymm...

  1. NLO QCD predictions for off-shell t anti t and t anti tH production and decay at a linear collider

    Energy Technology Data Exchange (ETDEWEB)

    Nejad, Bijan Chokoufe; Reuter, Juergen [DESY Hamburg (Germany). Theory Group; Kilian, Wolfgang [Zuerich Univ. (Switzerland). Physik-Inst.; Lindert, Jonas M.; Pozzorini, Stefano [Emmy-Noether Campus, Siegen (Germany); Weiss, Christian [DESY Hamburg (Germany). Theory Group; Zuerich Univ. (Switzerland). Physik-Inst.

    2016-09-15

    We present predictions for t anti t and t anti tH production and decay at future lepton colliders including non-resonant and interference contributions up to next-to-leading order (NLO) in perturbative QCD. The obtained precision predictions are necessary for a future precise determination of the top-quark Yukawa coupling, and allow for top-quark phenomenology in the continuum at an unprecedented level of accuracy. Simulations are performed with the automated NLO Monte-Carlo framework WHIZARD interfaced to the OpenLoops matrix element generator.

  2. NLO QCD Predictions for off-shell $t \\bar t$ and $t \\bar t H$ Production and Decay at a Linear Collider

    CERN Document Server

    Nejad, Bijan Chokoufé; Lindert, Jonas M; Pozzorini, Stefano; Reuter, Jürgen; Weiss, Christian

    2016-01-01

    We present predictions for $t \\bar t$ and $t \\bar t H$ production and decay at future lepton colliders including non-resonant and interference contributions up to next-to-leading order (NLO) in perturbative QCD. The obtained precision predictions are necessary for a future precise determination of the top-quark Yukawa coupling, and allow for top-quark phenomenology in the continuum at an unprecedented level of accuracy. Simulations are performed with the automated NLO Monte-Carlo framework WHIZARD interfaced to the OpenLoops matrix element generator.

  3. Incorporation of a platinum center in the pi-conjugated core of push-pull chromophores for nonlinear optics (NLO).

    Science.gov (United States)

    Durand, Raphaël J; Gauthier, Sébastien; Achelle, Sylvain; Kahlal, Samia; Saillard, Jean-Yves; Barsella, Alberto; Wojcik, Laurianne; Le Poul, Nicolas; Robin-Le Guen, Françoise

    2017-02-28

    In this article, we describe the synthesis, redox characteristics, and linear and nonlinear optical (NLO) properties of seven new unsymmetrical push-pull diacetylide platinum-based complexes. These D-π-Pt-π-A complexes incorporate pyranylidene ligands as pro-aromatic donor groups (D), diazine rings as electron-withdrawing groups (A), and various aromatic fragments (styryl or thienylvinyl) as π-linkers separating the platinum diacetylide unit from the donor and the acceptor groups. This is one of the first examples of push-pull chromophores incorporating a platinum center in the π-conjugated core. The NLO properties of these complexes were compared with those of their purely organic analogues. All compounds (organic and organometallic) exhibited positive μβ values, which dramatically increased upon methylation of the pyrimidine fragment. However, this increase was even more significant in the complexes due to the presence of platinum in the π-conjugated core. The effects of the linker on the redox and spectroscopic properties of the complexes are also discussed. In addition, DFT calculations were performed in order to gain further insight into the intramolecular charge transfer (ICT) occurring through the platinum center.

  4. Top quark mass determination from the energy peaks of b-jets and B-hadrons at NLO QCD

    CERN Document Server

    Agashe, Kaustubh; Franceschini, Roberto; Schulze, Markus

    2016-01-01

    We analyze the energy spectra of $single$ b-jets and B-hadrons resulting from the production and decay of top quarks within the SM at the LHC at the NLO QCD. For both hadrons and jets, we calculate the correlation of the peak of the spectrum with the top quark mass, considering the "energy-peak" as an observable to determine the top quark mass. Such a method is motivated by our previous work where we argued that this approach can have reduced sensitivity to the details of the production mechanism of the top quark, whether it is higher-order QCD effects or new physics contributions. As part of the NLO improvement over the original proposal, we assess the residual sensitivity of the extracted top quark mass to perturbative effects both in top quark production and decay. For a 1% jet energy scale uncertainty (and assuming negligible statistical error), the top quark mass can then be extracted using the energy-peak of b-jets with an error +- (1.2 (exp) + 0.6(th)) GeV. We note that recently the CMS collaboration r...

  5. Top quark mass determination from the energy peaks of b-jets and B-hadrons at NLO QCD

    Energy Technology Data Exchange (ETDEWEB)

    Agashe, Kaustubh [University of Maryland, Department of Physics, Maryland Center for Fundamental Physics, College Park, MD (United States); Franceschini, Roberto; Schulze, Markus [CERN, Theoretical Physics Department, Geneva (Switzerland); Kim, Doojin [CERN, Theoretical Physics Department, Geneva (Switzerland); University of Florida, Department of Physics, Gainesville, FL (United States)

    2016-11-15

    We analyze the energy spectra of single b-jets and B-hadrons resulting from the production and decay of top quarks within the SM at the LHC at the NLO QCD. For both hadrons and jets, we calculate the correlation of the peak of the spectrum with the top quark mass, considering the ''energy peak'' as an observable to determine the top quark mass. Such a method is motivated by our previous work where we argued that this approach can have reduced sensitivity to the details of the production mechanism of the top quark, whether it concerns higher-order QCD effects or new physics contributions. For a 1% jet energy scale uncertainty, the top quark mass can then be extracted using the energy peak of b-jets with an error ± (1.2(exp) + 0.6(th)) GeV. In view of the dominant jet energy scale uncertainty in the measurement using b-jets, we also investigate the extraction of the top quark mass from the energy peak of the corresponding B-hadrons which, in principle, can be measured without this uncertainty. The calculation of the B-hadron energy spectrum is carried out using fragmentation functions at NLO. The dependence on the fragmentation scale turns out to be the largest theoretical uncertainty in this extraction of top quark mass. (orig.)

  6. Measurement of the strange - antistrange asymmetry at NLO in QCD from NuTeV dimuon data

    Energy Technology Data Exchange (ETDEWEB)

    Mason, David Alexander [Univ. of Oregon, Eugene, OR (United States)

    2006-03-01

    A measurement of the asymmetry between the strange and antistrange quark distributions, from a next to leading order QCD analysis of dimuon events measured by the NuTeV experiment at Fermilab is presented. Neutrino charged current events with two muons in the final state provide a direct means for studying charm production and measuring the strange sea. NuTeV's sign selected beam allows independent measurement of the strange and antistrange seas. An improved measurement of the neutrino and antineutrino forward dimuon cross section tables, using the complete charged current event sample for normalization is performed. These tables are then analyzed at NLO to measure the strange and antistrange seas. Detector acceptance is modeled using an NLO charm cross section differential in all variables required. The strange quark distribution is found to have an integrated momentum weighted asymmetry of +0.00196 ± 0.00046(stat) ± 0.00045(syst) ± 0.00182(external). The charm mass is found to be 1.41 ± 0.10(stat) ± 0.08(syst) ± 0.12(external) GeV.

  7. Vibrational, NMR and UV-visible spectroscopic investigation and NLO studies on benzaldehyde thiosemicarbazone using computational calculations

    Science.gov (United States)

    Moorthy, N.; Prabakar, P. C. Jobe; Ramalingam, S.; Pandian, G. V.; Anbusrinivasan, P.

    2016-04-01

    In order to investigate the vibrational, electronic and NLO characteristics of the compound; benzaldehyde thiosemicarbazone (BTSC), the XRD, FT-IR, FT-Raman, NMR and UV-visible spectra were recorded and were analysed with the calculated spectra by using HF and B3LYP methods with 6-311++G(d,p) basis set. The XRD results revealed that the stabilized molecular systems were confined in orthorhombic unit cell system. The cause for the change of chemical and physical properties behind the compound has been discussed makes use of Mulliken charge levels and NBO in detail. The shift of molecular vibrational pattern by the fusing of ligand; thiosemicarbazone group with benzaldehyde has been keenly observed. The occurrence of in phase and out of phase molecular interaction over the frontier molecular orbitals was determined to evaluate the degeneracy of the electronic energy levels. The thermodynamical studies of the temperature region 100-1000 K to detect the thermal stabilization of the crystal phase of the compound were investigated. The NLO properties were evaluated by the determination of the polarizability and hyperpolarizability of the compound in crystal phase. The physical stabilization of the geometry of the compound has been explained by geometry deformation analysis.

  8. Growth and characterization of novel organic 3-Hydroxy Benzaldehyde-N-methyl 4 Stilbazolium Tosylate crystals for NLO applications

    Science.gov (United States)

    Jagannathan, K.; Umarani, P.; Ratchagar, V.; Ramesh, V.; Kalainathan, S.

    2016-01-01

    The 3-Hydroxy Benzaldehyde-N-methyl 4-Stilbazolium Tosylate (3- HBST) is a new organic NLO crystal and it is a new derivative in stilbazolium tosylate family. In this work we have synthesized 3-HBST and the single crystal was grown by conventional slow cooling method. The structure and lattice parameters of the grown crystal were determined by the single crystal X-ray diffraction (XRD) technique and it is exhibiting good crystalline nature which is observed from the powder XRD. In order to check the crystalline quality the rocking curve was recorded using multi crystal X-ray diffractometer. The functional groups were identified from both FTIR and NMR spectral analyses. The π-π* and n-π* optical transition energy levels were estimated from the absorption peaks. The NLO property was confirmed by measuring relative SHG efficiency by Kurtz powder test; it shows 24 times higher SHG efficiency than that of urea. In order to test the mechanical stability the Vickers and Knoop micro hardness measurement were carried out and found that the micro hardness number decreases with increasing load. The melting point was determined from Differential Scanning Colorimetry (DSC).

  9. A High Laser Damage Threshold and a Good Second-Harmonic Generation Response in a New Infrared NLO Material: LiSm3SiS7

    Directory of Open Access Journals (Sweden)

    Ni Zhen

    2016-09-01

    Full Text Available A series of new infrared nonlinear optical (IR NLO materials, LiRe3MS7 (Re = Sm, Gd; M = Si, Ge, have been successfully synthesized in vacuum-sealed silica tubes via a high-temperature solid-state method. All of them crystallize in the non-centrosymmetric space group P63 of the hexagonal system. In their structures, LiS6 octahedra connect with each other by sharing common faces to form infinite isolated one-dimensional ∞[LiS3]n chains along the 63 axis. ReS8 polyhedra share edges and corners to construct a three-dimensional tunnel structure with ∞[LiS3]n chains located inside. Remarkably, LiSm3SiS7 shows promising potential as one new IR NLO candidate, including a wide IR transparent region (0.44–21 μm, a high laser damage threshold (LDT (3.7 × benchmark AgGaS2, and a good NLO response (1.5 × AgGaS2 at a particle size between 88 μm and 105 μm. Dipole-moment calculation was also used to analyze the origin of NLO responses for title compounds.

  10. Electroweak top-quark pair production at the LHC with Z ' bosons to NLO QCD in POWHEG

    Science.gov (United States)

    Bonciani, Roberto; Ježo, Tomáš; Klasen, Michael; Lyonnet, Florian; Schienbein, Ingo

    2016-02-01

    We present the calculation of the NLO QCD corrections to the electroweak production of top-antitop pairs at the CERN LHC in the presence of a new neutral gauge boson. The corrections are implemented in the parton shower Monte Carlo program POWHEG. Standard Model (SM) and new physics interference effects are properly taken into account. QED singularities, first appearing at this order, are consistently subtracted. Numerical results are presented for SM and Z ' total cross sections and distributions in invariant mass, transverse momentum, azimuthal angle and rapidity of the top-quark pair. The remaining theoretical uncertainty from scale and PDF variations is estimated, and the potential of the charge asymmetry to distinguish between new physics models is investigated for the Sequential SM and a leptophobic topcolor model.

  11. Electroweak top-quark pair production at the LHC with $Z'$ bosons to NLO QCD in POWHEG

    CERN Document Server

    Bonciani, R; Klasen, M; Lyonnet, F; Schienbein, I

    2015-01-01

    We present the calculation of the NLO QCD corrections to the electroweak production of top-antitop pairs at the CERN LHC in the presence of a new neutral gauge boson. The corrections are implemented in the parton shower Monte Carlo program POWHEG. Standard Model (SM) and new physics interference effects are properly taken into account. QED singularities, first appearing at this order, are consistently subtracted. Numerical results are presented for SM and $Z'$ total cross sections and distributions in invariant mass, transverse momentum, azimuthal angle and rapidity of the top-quark pair. The remaining theoretical uncertainty from scale and PDF variations is estimated, and the potential of the charge asymmetry to distinguish between new physics models is investigated for the Sequential SM and a leptophobic topcolor model.

  12. Design, synthesis, and characterization of a novel class of tunable chromophores for second- and third-order NLO applications

    Science.gov (United States)

    Attias, Andre-Jean; Leclerc, Nicolas; Chen, Qiying; Sargent, Edward H.; Schull, Guillaume; Charra, Fabrice

    2004-10-01

    We describe a general approach for the synthesis of 6,6'-(disubstituted)-3,3'-bipyridine based chromophores. This combinatorial type strategy is based on (i) the synthesis of a library of conjugated building blocks end-capped with electron donor or acceptor groups, and (ii) their homo- or cross-coupling. The compounds are either dipolar (push-pull molecules) or apolar (symmetric D-A-A-D) molecules. Depending on the building blocks, we are able to tune both the structural and NLO properties of the chromophores. For example, the D-A-A-D structure possesses ultrafast nonresonant nonlinearity around 1550 nm with excellent figures of merit, as well as TPA in the visible and NIR ranges.

  13. Conformational analysis, UV-VIS, MESP, NLO and NMR studies of 6-methoxy-1,2,3,4-tetrahydronaphthalene.

    Science.gov (United States)

    Arivazhagan, M; Kavitha, R; Subhasini, V P

    2014-07-15

    The detailed HF and B3LYP/6-311++G(d,p) comparative studies on the complete FT-IR and FT-Raman spectra of 6-methoxy-1,2,3,4-tetrahydronaphthalene [MTHN] have been studied. In view of the special properties and uses, the present investigation has been undertaken to provide a satisfactorily vibrational analysis of 6-methoxy-1,2,3,4-tetrahydronaphthalene. Therefore, a thorough Raman, IR, molecular electrostatic potential (MESP), non-linear optical (NLO) properties, UV-VIS, HOMO-LUMO and NMR spectroscopic investigation are reported complemented by B3LYP theoretical predictions with basis set 6-311++G(d,p) to provide novel insight on vibrational assignments and conformational stability of MTHN. Potential energy surface scans (PES) of the CH3 group are undertaken to shed light on the rather complicated conformational interchanges in the compound under investigation.

  14. A QCD space-time analysis of quarkonium formation and evolution in hadronic collisions

    CERN Document Server

    Kinder-Geiger, Klaus

    1998-01-01

    The production of heavy quarkonium as QQbar bound-states in hadron-hadron collisions is considered within the framework of a space-time description, combining parton-cascade evolution with a coalescence model for bound-state formation. The `hard' production of the initial QQbar, directly or via gluon fragmentation and including both color-singlet and color-octet contributions, is calculated from the PQCD cross-sections. The subsequent development of the QQbar system is described within a space-time generalization of the DGLAP parton-evolution formalism in position- and momentum-space. The actual formation of the bound-states is accomplished through overlap of the QQbar pair and a spectrum of quarkonium wave-functions. This coalescence can only occur after sufficent gluon radiation reduces the QQbar relative velocity to a value commensurate with the non-relativistic kinematics of these bound systems. The presence of gluon participants in the cascade then is both necessary and leads to the natural inclusion of ...

  15. Dipole factorization for DIS at NLO I: Loop correction to the photon to quark-antiquark light-front wave-functions

    CERN Document Server

    Beuf, Guillaume

    2016-01-01

    The one-loop QCD corrections to the light-front wave-function for the quark-antiquark Fock state inside a transverse or longitudinal off-shell photon are explicitly calculated, both in full momentum space and in mixed space (a.k.a. dipole space). These results provide one of the main contributions to virtual NLO corrections to many DIS observables (inclusive or not) in the dipole factorization formalism at low Bjorken x. In a follow-up article, these one-loop corrections are combined with earlier results on the wave-function for the quark-antiquark-gluon Fock state, in order to get the full set of NLO corrections to the DIS structure functions $F_2$ and $F_L$ in the dipole factorization formalism, valid at low Bjorken x.

  16. Complete QED NLO contributions to the reaction $e^+e^- \\to \\mu^+\\mu^-\\gamma$ and their implementation in the event generator PHOKHARA

    CERN Document Server

    Campanario, F; Gluza, J; Gunia, M; Riemann, T; Rodrigo, G; Yundin, V

    2013-01-01

    KLOE and Babar have an observed discrepancy of 2% to 5% in the invariant pion pair production cross section. These measurements are based on approximate NLO $ \\mu^+ \\mu^- \\gamma $ cross section predictions of the Monte Carlo event generator PHOKHARA7.0. In this article, the complete NLO radiative corrections to $ \\mu^+ \\mu^- \\gamma $ production are calculated and implemented in the Monte Carlo event generator PHOKHARA9.0. Numerical reliability is guaranteed by two independent approaches to the real and the virtual corrections. The novel features include the contribution of pentagon diagrams in the virtual corrections, which form a gauge-invariant set when combined with their box diagram partners. They may contribute to certain distributions at the percent level. Also the real emission was complemented with two-photon final state emission contributions not included in the generator PHOKHARA7.0. We demonstrate that the numerical influence reaches, for realistic charge-averaged experimental setups, not more than...

  17. Synthesis, growth, structural and HOMO and LUMO, MEP analysis of a new stilbazolium derivative crystal: A enhanced third-order NLO properties with a high laser-induced damage threshold for NLO applications

    Science.gov (United States)

    Senthil, K.; Kalainathan, S.; Hamada, F.; Yamada, M.; Aravindan, P. G.

    2015-08-01

    A new organic third-order nonlinear optical crystal from stilbazolium family 2-[2-(4-methoxy-phenyl) vinyl]-1-methyl-pyridinium tetrafluoroborate (4MSTB) has been synthesized and grown by slow evaporation method for the first time. The grown crystal structure was confirmed by single crystal X-ray diffraction analysis, and it is revealed that the grown crystal crystallized in a triclinic crystal system with centrosymmetric space group P 1 bar . The HOMO and LUMO energies were calculated for the grown crystal explains charge transfer takes place within the molecule and confirms the suitability of the title crystal for NLO applications. The presence of various vibration modes of expected functional groups was identified by FT-IR analysis. The transmittance ability of the grown crystal was also analyzed by using UV-Vis-NIR spectral studies and shows that the crystal has no absorption of light in the entire Vis-NIR region. The thermal stability of the title crystal has been investigated by TGA/DTA studies and revealed that the material was thermally stable up to the melting point, 193 °C. The hardness number, Meyer index, yield strength, and elastic stiffness constant has been estimated for the grown 4MSTB crystal using Vickers microhardness tester. Photoluminescence excitation studies showed green emission radiation occurred at 517 nm. The dielectric properties of the grown crystal have been analyzed as a function of temperature over a wide range of frequency (50 Hz-5 MHz) by using LCR meter. The result of ac electrical conductivity of 4MSTB was found to be 5.25 × 10-5 (Ω m)-1. The laser damage threshold (LDT) energy for the grown crystal has been measured by using a Q-switched Nd:YAG laser as a source in single-shot mode (1064 nm, 10 Hz, 420 mJ). The result of LDT indicates that grown title crystal has excellent resistance to laser radiation than those of known some inorganic NLO materials. The chemical etching studies were carried out to assess the perfection of

  18. New Meta Nanomaterials Extension II of Optical Enhancement and Photorefractive Two-Beam Coupling - Synthesis and Fabrication of Quantum Dot NLO Polymer Composites

    Science.gov (United States)

    2015-07-09

    of CdS(MPS) are not affecting the spectrum of the composite. Both polymer and composite absorb at 423 nm(Figure 8);only a slight baseline is...of fluorescent quantum dot- polymer nanocomposites via frontal polymerization . Journal of Polymer Science Part A: Polymer Chemistry2010, 48, 2170. [2...of Quantum Dot NLO Polymer Composites Ronald Ziolo CIQA Final Report 07/09/2015 DISTRIBUTION A: Distribution approved for public release. AF Office

  19. Rb2Na(NO33: A Congruently Melting UV-NLO Crystal with a Very Strong Second-Harmonic Generation Response

    Directory of Open Access Journals (Sweden)

    Guohong Zou

    2016-04-01

    Full Text Available Crystals of congruently melting noncentrosymmetric (NCS mixed alkali metal nitrate, Rb2Na(NO33, have been grown through solid state reactions. The material possesses layers with NaO8 hexagonal bipyramids and NO3 triangular units. Rb+ cations are residing in the interlayer space. Each NaO8 hexagonal bipyramid shares its corners and edges with two and three NO3 units, respectively, in order to fulfill a highly dense stacking in the unit cell. The NaO8 groups share their six oxygen atoms in equatorial positions with three different NO3 groups to generate a NaO6-NO3 layer with a parallel alignment. The optimized arrangement of the NO3 groups and their high density in the structure together produce a strong second-harmonic generation (SHG response. Powder SHG measurements indicate that Rb2Na(NO33 has a strong SHG efficiency of five times that of KH2PO4 (KDP and is type I phase-matchable. The calculated average nonlinear optical (NLO susceptibility of Rb2Na(NO33 turns out to be the largest value among the NLO materials composed of only [NO3]− anion. In addition, Rb2Na(NO33 exhibits a wide transparency region ranging from UV to near IR, which suggests that the compound is a promising NLO material.

  20. Top-down holographic G-structure glueball spectroscopy at (N)LO in N and finite coupling

    Energy Technology Data Exchange (ETDEWEB)

    Sil, Karunava; Yadav, Vikas; Misra, Aalok [Indian Institute of Technology, Department of Physics, Roorkee, Uttaranchal (India)

    2017-06-15

    The top-down type IIB holographic dual of large-N thermal QCD as constructed in Mia et al. (Nucl Phys B 839:187, 2010) involving a fluxed resolved warped deformed conifold, its delocalized type IIA Strominger-Yau-Zaslow-mirror (SYZ-mirror) as well as its M-theory uplift constructed in Dhuria and Misra (JHEP 1311:001, 2013) - both in the finite coupling g{sub s} NLO) in N and find a (g{sub s}M{sup 2})/(N)(g{sub s}N{sub f})-suppression similar to and further validating semi-universality of NLO corrections to transport coefficients, observed in Sil and Misra (Eur Phys J C 76(11):618, 2016). (orig.)

  1. Off-shell top quarks with one jet at the LHC: a comprehensive analysis at NLO QCD

    Energy Technology Data Exchange (ETDEWEB)

    Bevilacqua, G. [MTA-DE Particle Physics Research Group, University of Debrecen,H-4010 Debrecen (Hungary); Hartanto, H.B.; Kraus, M.; Worek, M. [Institute for Theoretical Particle Physics and Cosmology, RWTH Aachen University,D-52056 Aachen (Germany)

    2016-11-17

    We present a comprehensive study of the production of top quark pairs in association with one hard jet in the di-lepton decay channel at the LHC. Our predictions, accurate at NLO in QCD, focus on the LHC Run II with a center-of-mass energy of 13 TeV. All resonant and non-resonant contributions at the perturbative order O(α{sub s}{sup 4}α{sup 4}) are taken into account, including irreducible backgrounds to tt̄j production, interferences and off-shell effects of the top quark and the W gauge boson. We extensively investigate the dependence of our results upon variation of renormalisation and factorisation scales and parton distribution functions in the quest for an accurate estimate of the theoretical uncertainties. Additionally, we explore a few possibilities for a dynamical scale choice with the goal of stabilizing the perturbative convergence of the differential cross sections far away from the tt̄ threshold. Results presented here are particularly relevant for searches of new physics as well as for precise measurements of the top-quark fiducial cross sections and top-quark properties at the LHC.

  2. Techniques for the treatment of IR divergences in decay processes at NLO and application to the top-quark decay.

    Science.gov (United States)

    Basso, Lorenzo; Dittmaier, Stefan; Huss, Alexander; Oggero, Luisa

    We present the extension of two general algorithms for the treatment of infrared singularities arising in electroweak corrections to decay processes at next-to-leading order: the dipole subtraction formalism and the one-cutoff slicing method. The former is extended to the case of decay kinematics which has not been considered in the literature so far. The latter is generalised to production and decay processes with more than two charged particles, where new "surface" terms arise. Arbitrary patterns of massive and massless external particles are considered, including the treatment of infrared singularities in dimensional or mass regularisation. As an application of the two techniques we present the calculation of the next-to-leading order QCD and electroweak corrections to the top-quark decay width including all off-shell and decay effects of intermediate [Formula: see text] bosons. The result, e.g., represents a building block of a future calculation of NLO electroweak effects to off-shell top-quark pair ([Formula: see text]) production. Moreover, this calculation can serve as the first step towards an event generator for top-quark decays at next-to-leading order accuracy, which can be used to attach top-quark decays to complicated many-particle top-quark processes, such as for [Formula: see text] or [Formula: see text].

  3. Assessment of conformational, spectral, antimicrobial activity, chemical reactivity and NLO application of Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone)

    Science.gov (United States)

    Rawat, Poonam; Singh, R. N.

    2015-04-01

    An orange colored pyrrole dihydrazone: Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone) (PDBO) has been synthesized by reaction of oxalic acid dihydrazide with 2,5 diformyl-1H-pyrrole and has been characterized by spectroscopic analysis (1H, 13C NMR, UV-visible, FT-IR and DART Mass). The properties of the compound has been evaluated using B3LYP functional and 6-31G(d,p)/6-311+G(d,p) basis set. The symmetric (3319, 3320 cm-1) and asymmetric (3389, 3382 cm-1) stretching wave number confirm free NH2 groups in PDBO. NBO analysis shows, inter/intra molecular interactions within the molecule. Topological parameters have been analyzed by QTAIM theory and provide the existence of intramolecular hydrogen bonding (N-H⋯O). The local reactivity descriptors analyses determine the reactive sites within molecule. The calculated first hyperpolarizability value (β0 = 23.83 × 10-30 esu) of pyrrole dihydrazone shows its suitability for non-linear optical (NLO) response. The preliminary bioassay suggested that the PDBO exhibits relatively good antibacterial and fungicidal activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Candida albicans, Aspergillus niger. The local reactivity descriptors - Fukui functions (fk+, fk-), local softnesses (sk+, sk-) and electrophilicity indices (ωk+, ωk-) analyses have been used to determine the reactive sites within molecule.

  4. Heavy Quark Production in CC and NC DIS and The Structure of Real and Virtual Photons in NLO QCD

    CERN Document Server

    Schienbein, I

    2001-01-01

    This thesis consists of two parts. In the first part heavy quark production in neutral current and charged current DIS is studied within the variable flavor number scheme of Aivazis, Collins, Olness, and Tung (ACOT). For this purpose all the relevant partonic subprocesses have been calculated to order O(\\alpha_s^1) for general masses and couplings taking into account massive initial state quark-partons as needed in the variable flavor number scheme of ACOT. By the calculation of the before missing radiative corrections to scattering amplitudes on massive quark partons the ACOT scheme could be completed to full order O(\\alpha_s^1). These results might also prove useful for studying the intrinsic charm content of nucleons. In the second part the parton content of pions and real and virtual photons is analyzed in leading order (LO) and next-to-leading oder (NLO) QCD within the framework of the radiative parton model of Gl\\"uck, Reya, and Vogt (GRV). Furthermore, the factorization of the cross section for the pro...

  5. A posteriori inclusion of parton density functions in NLO QCD final-state calculations at hadron colliders: The APPLGRID Project

    CERN Document Server

    Carli, Tancredi; Cooper-Sarkar, Amanda; Gwenlan, Claire; Salam, Gavin P; Siegert, Frank; Starovoitov, Pavel; Sutton, Mark

    2010-01-01

    A method to facilitate the consistent inclusion of cross-section measurements based on complex final-states from HERA, TEVATRON and the LHC in proton parton density function (PDF) fits has been developed. This can be used to increase the sensitivity of LHC data to deviations from Standard Model predictions. The method stores perturbative coefficients of NLO QCD calculations of final-state observables measured in hadron colliders in look-up tables. This allows the posteriori inclusion of parton density functions (PDFs), and of the strong coupling, as well as the a posteriori variation of the renormalisation and factorisation scales in cross-section calculations. The main novelties in comparison to original work on the subject are the use of higher-order interpolation, which substantially improves the trade-off between accuracy and memory use, and a CPU and computer memory optimised way to construct and store the look-up table using modern software tools. It is demonstrated that a sufficient accuracy on the cro...

  6. Synthesis, structural and spectral characterization of a novel NLO crystal N,N‧-diphenylguanidinium picrate: diacetone solvate

    Science.gov (United States)

    Shanmugavadivu, T.; Dhandapani, M.; Naveen, S.; Lokanath, N. K.

    2017-09-01

    An organic NLO active material N,N‧-diphenylguanidinium picrate: diacetone solvate (C13H14N3+. C6H2N3O7-. 2C3H6O) (DPGPD) was synthesized and single crystals were grown by slow evaporation-solution growth technique at room temperature. DPGPD crystallizes in monoclinic crystal system with noncentrosymmetric space group, Cc confirmed by single crystal X-ray diffraction analysis. The presence of various functional groups was identified from FT-IR spectral analysis and the proton transfer during the formation of compound was confirmed by NMR spectroscopic techniques. The thermal stability was investigated by TG/DTA analyses. Optical transmittance was measured by UV-Vis-NIR spectroscopy and band gap energy was calculated. Photoluminescence spectrum was used to explore its applicability towards laser diodes. Dielectric property of the material was ascertained at different temperatures and it is found that the grown crystal has higher dielectric constant in low frequencies. Photoconductivity study revealed that DPGPD exhibits positive photoconductivity. SHG property was found to be 0.6 times higher than that of KDP.

  7. Off-shell Top Quarks with One Jet at the LHC: A comprehensive analysis at NLO QCD

    CERN Document Server

    Bevilacqua, G; Kraus, M; Worek, M

    2016-01-01

    We present a comprehensive study of the production of top quark pairs in association with one hard jet in the di-lepton decay channel at the LHC. Our predictions, accurate at NLO in QCD, focus on the LHC Run II with a center-of-mass energy of 13 TeV. All resonant and non-resonant contributions at the perturbative order ${\\cal O}(\\alpha_s^4 \\alpha^4)$ are taken into account, including irreducible backgrounds to $t\\bar{t}j$ production, interferences and off-shell effects of the top quark and the $W$ gauge boson. We extensively investigate the dependence of our results upon variation of renormalisation and factorisation scales and parton distribution functions in the quest for an accurate estimate of the theoretical uncertainties. Additionally, we explore a few possibilities for a dynamical scale choice with the goal of stabilizing the perturbative convergence of the differential cross sections far away from the $t\\bar{t}$ threshold. Results presented here are particularly relevant for searches of new physics as...

  8. Investigation of gamma radiation effect on chemical properties and surface morphology of some nonlinear optical (NLO) single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ahlam, M.A., E-mail: omaymn771@yahoo.com [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India); Ravishankar, M.N. [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India); Vijayan, N. [Materials Characterization Division, National Physical Laboratory, New Delhi 110 012 (India); Govindaraj, G. [Department of Physics, Pondicherry University, Pondicherry 605 014 (India); Siddaramaiah [Department of Polymer and Technology, Sri Jayachamarajendra College of Engineering, Mysore 570 006 (India); Gnana Prakash, A.P., E-mail: gnanaprakash@physics.uni-mysore.ac.in [Department of Studies in Physics, University of Mysore, Manasagangotri, Mysore 570 006, Karnataka (India)

    2012-05-01

    The effect of Co-60 gamma irradiation on L-alanine cadmium chloride (LACC), L-alanine doped potassium dihydrogen orthophosphate (KDP) and L-arginine doped KDP nonlinear optical (NLO) single crystals were studied in doses ranging from 100 krad to 6 Mrad. The crystals were grown by slow evaporation method at room temperature. The effects of gamma irradiation on the chemical, surface morphology, DC electrical conductivity, thermal and mechanical properties of the grown crystals have been studied. The functional groups of unirradiated and irradiated crystals have been identified and confirmed by Fourier transform infrared (FTIR) studies. Scanning electron microscopy (SEM) of irradiated crystals shows some morphological changes in the crystals. The dc conductivity of LACC and L-alanine doped KDP crystals were found to increase with increase in radiation dose whereas in case of L-arginine doped KDP crystals, the dc conductivity was found to decrease with increase in radiation dose. Differential scanning calorimetry (DSC) thermograms reveals that there is no significant change in the melting point of the crystals after irradiation and the crystals does not decompose as a result of irradiation. The mechanical behavior of both unirradiated and irradiated crystals is explained with the indentation effects using Vicker's microhardness tester. The Vicker's hardness number H{sub V} and Mayer's index 'n' has been estimated and confirms that LACC belong to the hard materials.

  9. Investigation of gamma radiation effect on chemical properties and surface morphology of some nonlinear optical (NLO) single crystals

    Science.gov (United States)

    Ahlam, M. A.; Ravishankar, M. N.; Vijayan, N.; Govindaraj, G.; Siddaramaiah; Gnana Prakash, A. P.

    2012-05-01

    The effect of Co-60 gamma irradiation on L-alanine cadmium chloride (LACC), L-alanine doped potassium dihydrogen orthophosphate (KDP) and L-arginine doped KDP nonlinear optical (NLO) single crystals were studied in doses ranging from 100 krad to 6 Mrad. The crystals were grown by slow evaporation method at room temperature. The effects of gamma irradiation on the chemical, surface morphology, DC electrical conductivity, thermal and mechanical properties of the grown crystals have been studied. The functional groups of unirradiated and irradiated crystals have been identified and confirmed by Fourier transform infrared (FTIR) studies. Scanning electron microscopy (SEM) of irradiated crystals shows some morphological changes in the crystals. The dc conductivity of LACC and L-alanine doped KDP crystals were found to increase with increase in radiation dose whereas in case of L-arginine doped KDP crystals, the dc conductivity was found to decrease with increase in radiation dose. Differential scanning calorimetry (DSC) thermograms reveals that there is no significant change in the melting point of the crystals after irradiation and the crystals does not decompose as a result of irradiation. The mechanical behavior of both unirradiated and irradiated crystals is explained with the indentation effects using Vicker's microhardness tester. The Vicker's hardness number HV and Mayer's index 'n' has been estimated and confirms that LACC belong to the hard materials.

  10. Spectroscopic investigation, HOMO-LUMO and NLO studies on L-histidinium maleate based on DFT approach

    Science.gov (United States)

    Dhanavel, S.; Stephen, A.; Asirvatham, P. Samuel

    2017-05-01

    The molecular structure of the title compound L-Histidinium Maleate (LHM) was constructed and optimized based on Density Functional Theory method (DFT-B3LYP) with the 6-31G (d,p) basis set. The fundamental vibrational spectral assignment was analyzed with the aid of optimized structure of LHM. The study on electronic properties such as, HOMO-LUMO energies and absorption wavelength were performed using Time dependent DFT (TD-DFT) approach which reveals that energy transfer occur within the molecule. 13C NMR chemical shift values were measured using Gauge independent atomic orbital method (GIAO) and the obtained values are in good agreement with the reported experimental values. Hardness, ionization potential and electrophilicity index also calculated. The electric dipole moment (μtot) and hyperpolarizability (βtot) values of the investigated molecules were computed. The calculated value (β) was 3.7 times higher than that of urea, which confirms the LHM molecule is a potential candidate for NLO applications.

  11. Assessment of conformational, spectral, antimicrobial activity, chemical reactivity and NLO application of Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone).

    Science.gov (United States)

    Rawat, Poonam; Singh, R N

    2015-04-05

    An orange colored pyrrole dihydrazone: Pyrrole-2,5-dicarboxaldehyde bis(oxaloyldihydrazone) (PDBO) has been synthesized by reaction of oxalic acid dihydrazide with 2,5 diformyl-1H-pyrrole and has been characterized by spectroscopic analysis (1H, 13C NMR, UV-visible, FT-IR and DART Mass). The properties of the compound has been evaluated using B3LYP functional and 6-31G(d,p)/6-311+G(d,p) basis set. The symmetric (3319, 3320 cm(-1)) and asymmetric (3389, 3382 cm(-1)) stretching wave number confirm free NH2 groups in PDBO. NBO analysis shows, inter/intra molecular interactions within the molecule. Topological parameters have been analyzed by QTAIM theory and provide the existence of intramolecular hydrogen bonding (N-H⋯O). The local reactivity descriptors analyses determine the reactive sites within molecule. The calculated first hyperpolarizability value (β0=23.83×10(-30) esu) of pyrrole dihydrazone shows its suitability for non-linear optical (NLO) response. The preliminary bioassay suggested that the PDBO exhibits relatively good antibacterial and fungicidal activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Candida albicans, Aspergillus niger. The local reactivity descriptors--Fukui functions (fk+, fk-), local softnesses (sk+, sk-) and electrophilicity indices (ωk+, ωk-) analyses have been used to determine the reactive sites within molecule. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Completing NLO QCD Corrections for Tree Level Non-Leptonic Delta F = 1 Decays Beyond the Standard Model

    CERN Document Server

    Buras, Andrzej J

    2012-01-01

    In various extensions of the Standard Model (SM) tree level non-leptonic decays of hadrons receive contributions from new heavy gauge bosons and scalars. Prominent examples are the right-handed W' bosons in left-right symmetric models and charged Higgs (H^\\pm) particles in models with extended scalar sector like two Higgs doublet models and supersymmetric models. Even in the case of decays with four different quark flavours involved, to which penguin operators cannot contribute, twenty linearly independent operators, instead of two in the SM, have to be considered. Anticipating the important role of such decays at the LHCb, KEKB and Super-B in Rome and having in mind future improved lattice computations, we complete the existing NLO QCD formulae for these processes by calculating O(alpha_s) corrections to matching conditions for the Wilson coefficients of all contributing operators in the NDR-\\bar{MS} scheme. This allows to reduce certain unphysical scale and renormalization scheme dependences in the existing...

  13. NLO+NLL collider bounds, Dirac fermion and scalar dark matter in the B-L model

    Energy Technology Data Exchange (ETDEWEB)

    Klasen, Michael [Westfaelische Wilhelms-Universitaet Muenster, Institut fuer Theoretische Physik, Muenster (Germany); Lyonnet, Florian [Southern Methodist University, Dallas, TX (United States); Queiroz, Farinaldo S. [Max-Planck-Institut fuer Kernphysik, Particle and Astroparticle Physics Division, Heidelberg (Germany)

    2017-05-15

    Baryon and lepton numbers being accidental global symmetries of the Standard Model (SM), it is natural to promote them to local symmetries. However, to preserve anomaly-freedom, only combinations of B-L are viable. In this spirit, we investigate possible dark matter realizations in the context of the U(1){sub B-L} model: (i) Dirac fermion with unbroken B-L; (ii) Dirac fermion with broken B-L; (iii) scalar dark matter; (iv) two-component dark matter. We compute the relic abundance, direct and indirect detection observables and confront them with recent results from Planck, LUX-2016, and Fermi-LAT and prospects from XENON1T. In addition to the well-known LEP bound M{sub Z}{sup {sub '}}/g{sub BL} >or similar 7 TeV, we include often ignored LHC bounds using 13 TeV dilepton (dimuon + dielectron) data at next-to-leading order plus next-to-leading logarithmic accuracy. We show that, for gauge couplings smaller than 0.4, the LHC gives rise to the strongest collider limit. In particular, we find M{sub Z}{sup {sub '}}/g{sub BL} > 8.7 TeV for g{sub BL} = 0.3. We conclude that the NLO+NLL corrections improve the dilepton bounds on the Z{sup '} mass and that both dark matter candidates are only viable in the Z{sup '} resonance region, with the parameter space for scalar dark matter being fully probed by XENON1T. Lastly, we show that one can successfully have a minimal two-component dark matter model. (orig.)

  14. Vibrational spectroscopic and thermo dynamical property studies, Fukui functions, HOMO-LUMO, NLO, NBO and crystal structure analysis of a new Schiff base bearing phenoxy-imine group

    Science.gov (United States)

    Ceylan, Ümit; Çapan, Ali; Yalçın, Şerife Pınar; Sönmez, Mehmet; Aygün, Muhittin

    2017-05-01

    This study covers the synthesis, structural characterization by experimental FT-IR, 1H NMR and 13C NMR, UV-Vis and single crystal XRD and comparison with theoretical calculations of a Schiff base compound bearing phenoxy group, C34H28N2O4 by using the DFT method 6-311G(d,p) basis set. The molecular geometry, the dipole moments, electrostatic potential, vibrational frequencies, HOMO-LUMO energy were calculated. NBO, NLO, thermodynamic properties and Fukui function were studied. In this work, theoretical values show good agreement with experimental values.

  15. Studies of tt+cc production with MadGraph5_aMC@NLO and Herwig++ for the ATLAS experiment

    CERN Document Server

    The ATLAS collaboration

    2016-01-01

    Studies of the simulation of ttcc at the LHC, at a centre-of-mass energy of 13 TeV, based on next-to-leading order calculations with MadGraph5_aMC@NLO matched to Herwig++ are presented. Samples with ttcc in the three flavour scheme, in a next-to-leading order matrix element are compared to an inclusive tt sample with the charm contribution coming from the parton shower. The effects of generator-level cuts, the functional form of the renormalization and factorization scales, and the starting scale of the parton shower are investigated.

  16. 无线传感网中NLoS环境下的ToA/AoA改进混合定位算法(英文)

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    An improved hybrid Time of Arrival (ToA)/ Angle of Arrival (AoA) location algorithm by adopting Gauss-Newton iterative algorithm is proposed. It is with the advantage of fast convergence and combining with the grid-search-based method to optimize the initial object coordinates of the iteration, meanwhile, under the condition of small measurement errors caused by noises of ToA and AoA, the algorithm performance can be improved effectively. In the Non-Line-of-Sight (NLoS) environments of the Wireless Sensor N...

  17. DM rate at NLO and the impact of SUSY-QCD-corrections to (co-)annihilation-processes on neutralino dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Harz, Julia [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Herrmann, Bjoern [Laboratoire d' Annecy de Physique Theorique, Annecy-le-Vieux (France); Klasen, Michael; Meinecke, Moritz; Steppeler, Patrick [Institute of Theoretical Physics Muenster (Germany); Kovarik, Karol [Karlsruher Institut fuer Technologie (KIT), Karlsruhe (Germany); Le Boulc' h, Quentin [Laboratoire de Physique Subatomique et de Cosmologie, Grenoble (France)

    2013-07-01

    A powerful method to constrain the parameter space of theories beyond the Standard Model is to compare the predicted dark matter relic density with cosmological precision measurements, in particular with WMAP- and the upcoming Planck-data. On the particle physics side, the main uncertainty on the relic density arises from the (co-)annihilation cross sections of the dark matter particle. After a motivation for including higher order corrections in the prediction of the relic density, the DM rate at NLO-project will be presented, a software package that allows for the computation of the neutralino (co-)annihilation cross sections including SUSY-QCD corrections at the one-loop level and the evaluation of their effect on the relic density using a link to the public codes MicrOMEGAs and DarkSUSY. Recent results of the impact of SUSY-QCD corrections on the neutralino (co-)annihilation cross section as well as further ongoing projects in the context of the DM rate at NLO-project are discussed.

  18. Theoretical Study of the N-(2,5-Methylphenyl)salicylaldimine Schiff Base Ligand: Atomic Charges, Molecular Electrostatic Potential, Nonlinear Optical (NLO) Effects and Thermodynamic Properties

    Energy Technology Data Exchange (ETDEWEB)

    Zeyrek, Tugrul C. [Turkish Atomic Energy Authority, Ankara (Turkmenistan)

    2013-08-15

    Optimized geometrical structure, atomic charges, molecular electrostatic potential, nonlinear optical (NLO) effects and thermodynamic properties of the title compound N-(2,5-methylphenyl)salicylaldimine (I) have been investigated by using ab initio quantum chemical computational studies. Calculated results showed that the enol form of (I) is more stable than keto form. The solvent effect was investigated for obtained molecular energies, hardneses and the atomic charge distributions of (I). Natural bond orbital and frontier molecular orbital analysis of the title compound were also performed. The total molecular dipole moment (μ), linear polarizability (α), and first-order hyperpolarizability (β) were calculated by B3LYP method with 6-31G(d), 6-31+G(d,p), 6-31++G(d,p), 6-311+G(d) and 6-311++G(d,p) basis sets to investigate the NLO properties of the compound (I). The standard thermodynamic functions were obtained for the title compound with the temperature ranging from 200 to 450 K.

  19. Structural characterization, vibrational study, NLO and DFT calculations of a novel organic sulfate monohydrate templated with (S)-(-)-2,6-diammonium-4,5,6,7-tetrahydrobenzothiazole

    Science.gov (United States)

    Barhoumi, Abir; Mhiri, Tahar; Dammak, Thameur; Suñol, Joan Josep; Belhouchet, Mohamed

    2017-01-01

    A single crystal of (S)-(-)-2,6-diammonium-4,5,6,7-tetrahydrobenzothiazole sulfate monohydrate has been synthesized and grown at room temperature by slow evaporation of aqueous solution. The studied compound crystallizes in the space group P212121 of the orthorhombic system with cell parameters a = 7.0014(12), b = 8.7631(15), c = 19.773(3) Å. We report the molecular structure and the theoretical and experimental vibrational spectra of the synthesized compound. The atomic arrangement, which is an alternation of organic inorganic layers linked together through hydrogen bonds, gives rise to three types of rings formed by the interconnection of organic-inorganic entities. The experimental FT-IR and the Raman spectra the synthesized compound were recorded and analyzed. The peaks assignment has been made unambiguously from the literature. To confirm the assignment, the experimental spectra were compared with theoretical spectra obtained with the Gaussian 98 program by the Density Functional Theory (DFT) method using B3LYP function with the LanL2DZ basis set. Moreover, to study the nonlinear optical (NLO) property of this compound, the hyperpolarizability βtot, the electric dipole μtot and the polarizability αtot were calculated using the DFT. Based on our calculation the synthesized compound has a non-zero hyperpolarizability suggesting that it may be used in some NLO applications.

  20. Experimental and theoretical studies of the second- and third-order NLO properties of a semi-organic compound: 6-Aminoquinolinium iodide monohydrate

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Pedro S. Pereira, E-mail: psidonio@pollux.fis.uc.pt [CEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra (Portugal); El Ouazzani, Hasnaa; Pranaitis, Mindaugas [Institut des Sciences et Technologies Moléculaires d’Angers, MOLTECH ANJOU, CNRS UMR 6200, Université d’Angers, 2 Bd Lavoisier, 49045 Angers Cedex (France); Silva, Manuela Ramos [CEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra (Portugal); Arranja, Cláudia T.; Sobral, Abilio J.F.N. [Department of Chemistry, University of Coimbra, P-3004-516 Coimbra (Portugal); Sahraoui, Bouchta [Institut des Sciences et Technologies Moléculaires d’Angers, MOLTECH ANJOU, CNRS UMR 6200, Université d’Angers, 2 Bd Lavoisier, 49045 Angers Cedex (France); Paixão, José A. [CEMDRX, Physics Department, University of Coimbra, P-3004-516 Coimbra (Portugal)

    2014-01-15

    Highlights: • Synthesis and structure of 6-aminoquinolinium iodide monohydrate is reported. • UV–vis absorption and fluorescence spectra are reported. • SHG and THG signals measured with the Maker fringes technique. • Hyperpolarizabilities calculated with the DFT and MP2 methods. • Behaviour of hybrid functionals corrected with ESP charges. - Abstract: A new semi-organic compound, 6-aminoquinolinium iodide monohydrate (I), has been synthesized and characterized by single crystal X-ray diffraction, UV–vis absorption and fluorescence spectroscopy and nonlinear optical (NLO) measurements. The second- and third-order NLO responses were investigated with the second- and third-harmonic Maker fringes techniques, carried out on thin films at a fundamental wavelength of 1064 nm. From the molecular structure, the molecular hyperpolarizability tensors were determined with density functional theory and second-order Møller–Plesset perturbation method. The second- and third-order susceptibility tensors of the reported crystal were evaluated using the oriented gas model with the Lorenz–Lorentz and the Wortmann–Bishop local-field corrections. The calculations using the Wortmann–Bishop local-field were able to reproduce the correct order of magnitude of the experimental third-order susceptibilities. The value of χ{sup (3)} obtained by summing the effective third-order polarizability calculated for the asymmetric unit surrounded by ESP-derived charges have also the same order of magnitude of the experimental.

  1. Experimental and theoretical studies of the second- and third-order NLO properties of a semi-organic compound: 6-Aminoquinolinium iodide monohydrate

    Science.gov (United States)

    Silva, Pedro S. Pereira; El Ouazzani, Hasnaa; Pranaitis, Mindaugas; Silva, Manuela Ramos; Arranja, Cláudia T.; Sobral, Abilio J. F. N.; Sahraoui, Bouchta; Paixão, José A.

    2014-01-01

    A new semi-organic compound, 6-aminoquinolinium iodide monohydrate (I), has been synthesized and characterized by single crystal X-ray diffraction, UV-vis absorption and fluorescence spectroscopy and nonlinear optical (NLO) measurements. The second- and third-order NLO responses were investigated with the second- and third-harmonic Maker fringes techniques, carried out on thin films at a fundamental wavelength of 1064 nm. From the molecular structure, the molecular hyperpolarizability tensors were determined with density functional theory and second-order Møller-Plesset perturbation method. The second- and third-order susceptibility tensors of the reported crystal were evaluated using the oriented gas model with the Lorenz-Lorentz and the Wortmann-Bishop local-field corrections. The calculations using the Wortmann-Bishop local-field were able to reproduce the correct order of magnitude of the experimental third-order susceptibilities. The value of χ obtained by summing the effective third-order polarizability calculated for the asymmetric unit surrounded by ESP-derived charges have also the same order of magnitude of the experimental.

  2. Electronic structure and nonlinear optical properties (NLO) of 2,4-di-aryl-1,5-benzothiazepine derivatives using DFT approach

    Science.gov (United States)

    Moustafa, H.; Elshakre, Mohamed E.; Elramly, Salwa

    2017-05-01

    The electronic structure of and NLO of 2,4-di-aryl-1,5-benzothiazepine and some of its derivatives are investigated theoretically at the B3LYP/6-311G**level of theory. The extent of delocalization and intramolecular charge transfer are estimated and discussed in terms of natural bond orbital analysis (NBO) and second order perturbation interactions between donor and acceptor MOs. The calculated EHOMO and ELUMO energies of the studied compounds can be used to calculate the global properties; chemical hardness (η), softness (S) and electronegativity (χ). The equilibrium geometries of the studied compounds are determined, and it was found that these geometries are non plannar. The choice of these substituents aims at creating a push- pull system on the 1,5-thiazepine basic structure which pave the way to understand their nonlinear optical properties. The calculated nonlinear optical parameters (NLO); polarizability (α), anisotropy of the polarizibility (Δα) and first order hyperpolarizibility (β) of the studied compounds show promising optical properties. 3D-plots of the molecular electrostatic potential (MEP) for some selected molecules are investigated and analyzed showing the distribution of electronic density of orbitals describing the electrophilic and nucleophilic sites of the selected molecules.

  3. Structure and second-order NLO property of the molecules bridged through n-vertex bis-substituted carborane (n=5, 6, 7)

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Density functional theory (DFT) B3LYP at 6-31G* level is employed to optimize the structures of the molecules bridged through n-vertex bis-substituted carborane (n=5, 6, 7) and combined with finite field (FF) formalism to calculate the second-order NLO properties. The results indicate that the structures of n-vertex bis-substituted carborane (n=5, 6, 7) are changed due to bridged donor and acceptor moieties. The distances between two C atoms are becoming longer. And the stability and dipole moment are influenced by changing substituted positions of C atoms. The isomers with the substituents connecting with C atoms of lower coordination number have better stability and larger values of polarizability. One-dimensional structure of the molecules bridged through n-vertex bis-substituted carborane (n=5, 6, 7) is in favor of intramolecular charge-transfer. Meanwhile, the isomer with a larger change of dipole moment has larger value of second-order NLO properties during the charge-transfer process.

  4. Fabrication and optical testing of hybrid SiO2: azo-polymer based planar waveguides for NLO/SHG laser emission

    Science.gov (United States)

    Torres-Zúñiga, V.; Morales-Saavedra, O. G.; Pérez-Martínez, A. L.

    2015-01-01

    Predesigned push-pull azo-dye polymers were homogeneously dispersed within a SiO2 sol-gel matrix synthesized via the sonogel (SG) route. High-quality spin-coated films were obtained with these hybrid structures in the liquid sol-phase. The spectroscopic UV- Vis analyses reveal the appropriate insertion of these organic compounds within the highly pure SG-environment whereas the thermal (DSC) analysis and photoacoustic measurements evidence the thermomechanical stability of the amorphous hybrid layers. As the optical attenuation, refractive index and film thickness values of the obtained films are adequate for opto-electronic applications; these hybrid films were implemented to fabricate optical waveguiding prototypes. In this sense, functional planar waveguides were fabricated for nonlinear optical (NLO) applications after performing a molecular ordering via a corona DC-poling procedure in order to achieve a macroscopic polar order (ferroelectric and noncentrosymmetric arrangement of the organic chromophores). The poled films were then able to exhibit stable NLO-waveguiding effects as excited with a Nd:YAG laser system in order to generate second harmonic waves travelling within the planar layer.

  5. Probing the littlest Higgs model with $T$ parity using di-Higgs events through $Z_H$-pair production at the LHC in NLO QCD

    CERN Document Server

    Liang-Wen, Chen; Wen-Gan, Ma; Wei-Hua, Li; Peng-Fei, Duan; Lei, Guo

    2014-01-01

    We investigate the di-Higgs events through $Z_H$-pair production at the CERN Large Hadron Collider including the pure next-to-leading order (NLO) QCD correction and the $gg$-fusion contribution in the framework of the littlest Higgs model with $T$ parity. We employ the diagram subtraction scheme in the QCD NLO calculations to avoid double counting and keep the convergence of the perturbative QCD description for the $Z_H$-pair production. We investigate the dependence of the leading order and QCD corrected integrated cross sections on the renormalization/factorization scale, and find that the total QCD corrections slightly reduce the scale uncertainty in the plotted range. By considering the subsequent decays of the intermediately produced $Z_H$ bosons and adopting the exclusive four-$b$-jet event selection criterion, the QCD correction provides considerable enhancement of the kinematic distributions for final decay products. We find that it is possible to select the signature of the $Z_H$-pair production from...

  6. Higgs production in association with a top-antitop pair in the Standard Model Effective Field Theory at NLO in QCD

    Energy Technology Data Exchange (ETDEWEB)

    Maltoni, Fabio; Vryonidou, Eleni [Centre for Cosmology, Particle Physics and Phenomenology (CP3),Université catholique de Louvain,B-1348 Louvain-la-Neuve (Belgium); Zhang, Cen [Department of Physics, Brookhaven National Laboratory,Upton, NY 11973 (United States)

    2016-10-24

    We present the results of the computation of the next-to-leading order QCD corrections to the production cross section of a Higgs boson in association with a top-antitop pair at the LHC, including the three relevant dimension-six operators (O{sub tφ},O{sub φG},O{sub tG}) of the standard model effective field theory. These operators also contribute to the production of Higgs bosons in loop-induced processes at the LHC, such as inclusive Higgs, Hj and HH production, and modify the Higgs decay branching ratios for which we also provide predictions. We perform a detailed study of the cross sections and their uncertainties at the total as well as differential level and of the structure of the effective field theory at NLO including renormalisation group effects. Finally, we show how the combination of information coming from measurements of these production processes will allow to constrain the three operators at the current and future LHC runs. Our results lead to a significant improvement of the accuracy and precision of the deviations expected from higher-dimensional operators in the SM in both the top-quark and the Higgs-boson sectors and provide a necessary ingredient for performing a global EFT fit to the LHC data at NLO accuracy.

  7. A New Copper(I) Complex Based on Imidazole and Triphenyl- phosphine Ligands: Synthesis, Structure, Third-Order NLO, and Fluorescence Properties

    Institute of Scientific and Technical Information of China (English)

    刘法谦; 金燕玲; 刘保成; 李荣勋; 邓月义; 李伟华; 建方方

    2012-01-01

    A new candidate [Cu(PPh3)2Him]Br (1, PPh3 =triphenylphosphine, Him= 1-H-imidazole) for nonlinear optical (NLO) materials has been synthesized and characterized crystallographically. The third-order NLO optical properties were measured by the Z-scan technique with an 8 ns pulsed laser at 532 nm. Compound 1 exhibits strong NLO absorptive abilities [a2=(61±5)×10^-12] and effective self-focusing performance [n2=(15±3)×10^-18 m^2·W^-1] in 1.01×10^-4 molodm 3 DMF solution. The compound also exhibits luminescence in DMF solution at room temperature and shows narrow emission with maximum at 382 nm. The electronic structure and photoluminescent process were investigated by means of TD-DFT calculations. The results suggest that the contribution to the frontier orbitals from the Cu-Br σ bond plays a crucial role in its linear optical properties, and the origin of luminescence is attrib- utable to the π* → n transitions.

  8. Push-pull 1,3-thiazolium-5-thiolates. Formation via concerted and stepwise pathways, and theoretical evaluation of NLO properties.

    Science.gov (United States)

    Cantillo, David; Avalos, Martín; Babiano, Reyes; Cintas, Pedro; Jiménez, José L; Light, Mark E; Palacios, Juan C; Rodríguez, Valentín

    2010-12-01

    The transformation of münchnones (mesoionic rings featuring the 1,3-oxazolium-5-olate core) into their sulfur counterparts (1,3-thiazolium-5-thiolates) by reaction with CS(2), pioneered by Huisgen and his group in the early 1970s, has been re-investigated in detail by means of both experimental and theoretical methods. The synthetic strategy can be tuned to incorporate donor and acceptor groups in appropriate positions. Calculations of molecular hyperpolarizabilities together with orbital topologies evidence that these sulfur-containing heterocycles exhibit nonlinear optical responses, thereby pointing to potential applications of mesoionic structures in the NLO field. From a mechanistic viewpoint, modeling of the whole systems at the B3LYP/6-31G(d) level reveals that concerted and stepwise pathways are operative depending on the substitution pattern of the parent münchnone, which also account for the experimental results.

  9. Computing decay rates for new physics theories with FeynRules  and MadGraph 5 _aMC@NLO

    CERN Document Server

    Alwall, Johan; Fuks, Benjamin; Mattelaer, Olivier; Öztürk, Deniz Gizem; Shen, Chia-Hsien

    2015-01-01

    We present new features of the FeynRules and MadGraph5/aMC@NLO programs for the automatic computation of decay widths that consistently include channels of arbitrary final-state multiplicity. The implementations are generic enough so that they can be used in the framework of any quantum field theory, possibly including higher-dimensional operators. We extend at the same time the conventions of the Universal FeynRules Output (or UFO) format to include decay tables and information on the total widths. We finally provide a set of representative examples of the usage of the new functions of the different codes in the framework of the Standard Model, the Higgs Effective Field Theory, the Strongly Interacting Light Higgs model and the Minimal Supersymmetric Standard Model and compare the results to available literature and programs for validation purposes.

  10. DFT calculations on molecular structure, spectral analysis, multiple interactions, reactivity, NLO property and molecular docking study of flavanol-2,4-dinitrophenylhydrazone

    Science.gov (United States)

    Singh, Ravindra Kumar; Singh, Ashok Kumar

    2017-02-01

    A new flavanol-2,4-dinitrophenylhydrazone (FDNP) was synthesized and its structure was confirmed by FT-IR, FT-Raman, 1H NMR, mass spectrometry and elemental analysis. All quantum chemical calculations were carried out at level of density functional theory (DFT) with B3LYP functional using 6-311++ G (d,p) basis atomic set. UV-Vis absorption spectra for the singlet-singlet transition computed for fully optimized ground state geometry using Time-Dependent-Density Functional Theory (TD-DFT) with CAM-B3LYP functional was found to be in consistent with that of experimental findings. Analysis of vibrational (FT-IR and FT-Raman) spectrum and their assignments has been done by computing Potential Energy Distribution (PED) using Gar2ped. HOMO-LUMO analysis was performed and reactivity descriptors were calculated. Calculated global electrophilicity index (ω = 7.986 eV) shows molecule to be a strong electrophile. 1H NMR chemical shift calculated with the help of gauge-including atomic orbital (GIAO) approach shows agreement with experimental data. Various intramolecular interactions were analysed by AIM approach. DFT computed total first static hyperpolarizability (β0 = 189.03 × 10-30 esu) indicates that title molecule can be used as attractive future NLO material. Solvent induced effects on the NLO properties studied by using self-consistent reaction field (SCRF) method shows that β0 value increases with increase in solvent polarity. To study the thermal behaviour of title molecule, thermodynamic properties such as heat capacity, entropy and enthalpy change at various temperatures have been calculated and reported. Molecular docking results suggests title molecule to be a potential kinase inhibitor and might be used in future for designing of new anticancer drug.

  11. Spectroscopic (FT-IR, FT-Raman, UV, NMR, NLO) investigation and molecular docking study of 1-(4-Methylbenzyl) piperazine

    Science.gov (United States)

    Subashini, K.; Periandy, S.

    2017-04-01

    The title compound, 1-(4-Methylbenzyl) piperazine, was analyzed by recording FT-IR (4000-400 cm-1) and FT-Raman (4000-100 cm-1) spectra in solid phase, 1H and 13C NMR in CDCl3 (deuterated chloroform) and UV spectrum (200-400 nm) in solid phase and in ethanol solution. The different conformers of the compound and their minimum energies were studied by potential energy surface scan, using semi-empirical method PM6. Density functional theory (DFT) calculation with 6-311++G (d, p) basis set along with B3LYP and B3PW91 functionals have been used to compute ground state molecular geometries and vibrational frequencies. The assignments of the vibrational spectra have carried out with the help of Potential Energy distribution (PED) analysis. Factor group analysis has also been tabulated. Charge distribution, Frontier Molecular Orbitals, UV-Vis spectra, Molecular Electrostatic Potential (MEP) maps, Non-linear optical (NLO) property and thermodynamic properties of the title compound at different temperatures, were determined using B3LYP functional along with 6-311++G (d, p) basis set. The theoretical 1H and 13C NMR chemical shifts were computed using B3LYP functional with 6-311++G (2d, p) basis sets. Natural Bond orbital analysis were computed and possible transitions were correlated with the electronic transitions. The title compound not only exhibits appreciable dipole moment and hyper polarizability (indicating good NLO properties) but also forms a stable complex with Bacillus cereus, (2HUC), with binding affinity -6.7 kcal/mol through molecular docking, suggesting that, it might exhibit inhibitory activity against Bacillus cereus.

  12. The growth with energy of exclusive $J/\\Psi$ and $\\Upsilon$ photo-production cross-sections and BFKL evolution

    CERN Document Server

    Hentschinski, Martin

    2016-01-01

    We investigate whether NLO BFKL evolution is capable to describe the energy dependence of the exclusive photo-production cross-section of vector mesons $J/\\Psi$ and $\\Upsilon$ on protons. Our description is based on available NLO BFKL fits of the proton impact factor in inclusive DIS, which allow us to construct the necessary scattering amplitude at zero momentum transfer $t=0$. Assuming an exponential drop-off with $t$, this result allows us to calculate the exclusive photoproduction cross-section. Comparing our results with both HERA data (measured by H1 and ZEUS collaborations in $ep$ collision) and LHC data (measured by ALICE, CMS and LHCb collaborations in ultra-peripheral $pp$ and $pPb$ collision) we find that our framework provides a very good description of the energy dependence of the $J/\\Psi$ and $\\Upsilon$ photoproduction cross-section, providing therefore further evidence for BFKL evolution at the LHC. The available fits of the proton impact factor require on the other hand an adjustment in the ov...

  13. The growth with energy of exclusive J/Ψ and ϒ photo-production cross-sections and BFKL evolution

    Science.gov (United States)

    Hentschinski, Martin

    2017-03-01

    We investigate whether NLO BFKL evolution is capable to describe the energy dependence of the exclusive photo-production cross-section of vector mesons J/Ψ and ϒ on protons. Our description is based on available NLO BFKL fits of the proton impact factor in inclusive DIS, which allow us to construct the necessary scattering amplitude at zero momentum transfer t = 0. Assuming an exponential drop-off with t, this result allows us to calculate the exclusive photoproduction cross-section. Comparing our results with both HERA data (measured by H1 and ZEUS collaborations in ep collision) and LHC data (measured by ALICE, CMS and LHCb collaborations in ultra-peripheral pp and pPb collision) we find that our framework provides a very good description of the energy dependence of the J/Ψ and ϒ photoproduction cross-section, providing therefore further evidence for BFKL evolution at the LHC. The available fits of the proton impact factor require on the other hand an adjustment in the overall normalization.

  14. Singularity-free Next-to-leading Order $\\Delta S= 1$ Renormalization Group Evolution and $\\epsilon_{K}^{\\prime}/\\epsilon_{K}$ in the Standard Model and Beyond

    CERN Document Server

    Kitahara, Teppei; Tremper, Paul

    2016-01-01

    The standard analytic solution of the renormalization group (RG) evolution for the $\\Delta S = 1$ Wilson coefficients involves several singularities. In practical applications one either regularizes these singularities or circumvents the problem by using numerical integrations. In this paper we derive a singularity-free solution of the next-to-leading order (NLO) RG equations, which greatly facilitates the calculation of $\\epsilon_K^{\\prime}$, the measure of direct $CP$ violation in $K\\to\\pi\\pi$ decays. Using our new RG evolution and the latest lattice results for the hadronic matrix elements, we calculate the ratio $\\epsilon_{K}^{\\prime}/\\epsilon_{K}$ (with $\\epsilon_{K}$ quantifying indirect $CP$ violation) in the Standard Model (SM) at NLO to $\\epsilon_{K}^{\\prime}/\\epsilon_{K} = ( 0.96 \\pm 4.96 ) \\times 10^{-4}$, which is 2.9$\\,\\sigma$ below the experimental value. We also present the evolution matrix in the high-energy regime for calculations of new physics contributions and derive easy-to-use approximat...

  15. Assessment of long-range corrected and conventional DFT functional for the prediction of second--order NLO properties and other molecular properties of N-(2-cyanoethyl)-N-butylaniline--a vibrational spectroscopy study.

    Science.gov (United States)

    Anitha, K; Balachandran, V

    2015-07-05

    Vibrational spectral analysis and quantum chemical computations based on density functional theory have been performed on the N-(2-cyanoethyl)-N-butylaniline. The geometry, structural properties, intermolecular hydrogen bond, and harmonic vibrational frequencies of the title molecule have been investigated with the help of DFT (B3LYP) and LC-DFT (CAM-B3LYP) method. Molecular electrostatic potential (MEP) have been performed. The various intramolecular interactions have been exposed by natural bond orbital analysis. The distribution of atomic charges and bending of natural hybrid orbitals also reflect the presence of intramolecular hydrogen bonding. Global reactivity and local reactivity descriptors of the title molecule have been calculated. The analysis of the electron density of HOMO and LUMO gives an idea of the delocalization and low value of energy gap indicated the electron transport in the molecule and thereby NLO activity. The effect of solvent on second-order NLO properties has been studied using polarized continuum model (PCM) in the tetrahydrofuran (THF) solution. The solvent leads to a slight enhancement of the NLO responses for the studied complexes relevant to their NLO responses in gas phase. The electronic absorption spectra were investigated by the TDDFT methods. The frequency-dependent first hyperpolarizabilities of the N-(2-cyanoethyl)-N-butylaniline were also evaluated. The (1)H and (13)C NMR chemical shifts have been calculated by gauge-indepedent atomic orbital (GIAO) method with B3LYP/6-311++G(d, p) approach. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Stellar evolution

    CERN Document Server

    Meadows, A J

    2013-01-01

    Stellar Evolution, Second Edition covers the significant advances in the understanding of birth, life, and death of stars.This book is divided into nine chapters and begins with a description of the characteristics of stars according to their brightness, distance, size, mass, age, and chemical composition. The next chapters deal with the families, structure, and birth of stars. These topics are followed by discussions of the chemical composition and the evolution of main-sequence stars. A chapter focuses on the unique features of the sun as a star, including its evolution, magnetic fields, act

  17. The approximation method for calculation of the exponent of the gluon distribution-$\\lambda_{g}$ and the structure function-$\\lambda_{S}$ at low $x$

    CERN Document Server

    Boroun, G R

    2014-01-01

    We present a set of formulae using the solution of the QCD Dokshitzer-Gribov-Lipatov-Altarelli-parisi (DGLAP) evolution equation to the extract of the exponent $\\lambda_g$ gluon distribution and $\\lambda_S$ structure function from the Regge- like behavior at low $x$. The exponents are found to be independent of $x$ and to increase linearly with ln$Q^{2}$ and compared with the most data from H1 Collaboration. We also calculated the structure function $F_{2}(x,Q^{2})$ and the gluon distribution $G(x,Q^{2})$ at low $x$ assuming the Regge- like behavior of the gluon distribution function at this limit and compared with NLO QCD fit to the H$1$ data, two Pomeron fit, multipole Pomeron exchange fit and MRST (A.D.Martin, R.G.Roberts, W.J.Stirling and R.S.Thorne), DL(A.Donnachie and P.V.Landshoff), NLO-GRV(M.Gluk, E.Reya and A.Vogt) fit results, respectively.

  18. Simulating Evolution

    Science.gov (United States)

    Stebbins, Robert C.; Allen, Brockenbrough

    1975-01-01

    Described are simulations that can be used to illustrate evolution by natural selection. Suggestions for simulating phenomena such as adaptive radiation, color match to background and vision of predators are offered. (BR)

  19. Schumpeter's Evolution

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    reworking of his basic theory of economic evolution in Development from 1934, and this reworking was continued in Cycles from 1939. Here Schumpeter also tried to handle the statistical and historical evidence on the waveform evolution of the capitalist economy. Capitalism from 1942 modified the model...... of economic evolution and added evolutionary contributions to other social sciences. History, which was published by his widow, was based on his evolutionary theory of the history of economic analysis. This sequential analysis of Schumpeter's six books demonstrates the progress he within his research......This draft of a book on Schumpeter is distributed for commenting. It is a stylised intellectual biography that focus on the emergence and extension of the Schumpeterian vision and analysis of economic and social evolution. The draft provides novel interpretations of Schumpeter's six major books. He...

  20. Schumpeter's Evolution

    DEFF Research Database (Denmark)

    Andersen, Esben Sloth

    This draft of a book on Schumpeter is distributed for commenting. It is a stylised intellectual biography that focus on the emergence and extension of the Schumpeterian vision and analysis of economic and social evolution. The draft provides novel interpretations of Schumpeter's six major books. He...... originally developed his evolutionary research programme in Wesen from 1908 by studying the inherent limitations of Neoclassical Economics. He presented core results on economic evolution and sketched an extension evolutionary analysis to all social sciences in Entwicklung from 1912. He made a partial...... reworking of his basic theory of economic evolution in Development from 1934, and this reworking was continued in Cycles from 1939. Here Schumpeter also tried to handle the statistical and historical evidence on the waveform evolution of the capitalist economy. Capitalism from 1942 modified the model...

  1. Growth, optical, thermal, mechanical and dielectric studies of sodium succinate hexahydrate (β phase) single crystal: A promising third order NLO material

    Science.gov (United States)

    Mageshwari, P. S. Latha; Priya, R.; Krishnan, S.; Joseph, V.; Das, S. Jerome

    2016-11-01

    A third order nonlinear optical (NLO)single crystals of sodium succinate hexahydrate (SSH) (β phase) has been grown by a slow evaporation growth technique using aqueous solution at ambient temperature. The lattice parameters and morphology of SSH were determined by single crystal X-ray diffraction analysis. SSH crystallizes in centrosymmetric monoclinic system with space group P 21 / c and the crystalline purity was analyzed by powder X-ray diffraction analysis. The UV-vis-NIR spectrum reveals that the crystal is transparent in the entire visible region. The recorded FT-IR spectrum verified the presence of various functional groups in the material. NMR analysis of the grown crystal confirms the structural elucidation and detects the major and minor functional groups present in the title compound. ICP-OES analysis proved the presence of sodium in SSH. TG-DTA/DSCanalysis was used to investigate the thermal stability of the material. The dielectric permittivity and dielectric loss of SSH were carried out as a function of frequency for different temperatures and the results were discussed. The mechanical stability was evaluated from Vicker's microhardness test. The third order nonlinear optical properties of SSH has been investigated employing Z-scan technique with He-Ne laser operating at 632.8 nm wavelength.

  2. Synthesis, characterization and theoretical investigations of the structure, electronic properties and third-order nonlinearity optics (NLO) of M(DPIP)2

    Science.gov (United States)

    Li, Kang; Tang, Guodong; Kou, ShanShan; Culnane, Lance F.; Zhang, Yu; Song, Yinglin; Li, Rongqing; Wei, Changmei

    2015-03-01

    Three complexes of M(DPIP)2 (M = Cu, Co, Zn as 1, 2, 3) were synthesized and characterized by elemental analysis, IR, UV-Vis, thermogravimetry, and X-ray diffraction. Their nonlinear optical properties were measured by the Z-scan technique and yielded a normalized transmittance of about 70% for complex 1 (45 μJ pulse), and 93% for complex 3 (68 μJ pulse at the focus point). The nonlinear absorption coefficient, β, is 1.4 × 10-11 m/W for 1 and 5.6 × 10-13 m/W for 3, and the third-order nonlinear refraction index, n2, is 1.0 × 10-18 m2/W for 3. Complex 1 shows self-defocusing property, while complex 3 exhibits self-focusing property. The thermogravimetric results show that the frame structure of compounds 1-3 begin to collapse at 400, 250 and 280 °C, respectively, which suggests that they elicit excellent thermal stability. This research aims to provide better understanding of these compounds, and offer preliminary explanations for the significant differences between compounds 1-3, in order to potentially help in the designing of future novel materials with NLO properties.

  3. Higgs production in association with a top-antitop pair in the Standard Model Effective Field Theory at NLO in QCD

    CERN Document Server

    Maltoni, Fabio; Zhang, Cen

    2016-01-01

    We present the results of the computation of the next-to-leading order QCD corrections to the production cross section of a Higgs boson in association with a top-antitop pair at the LHC, including the three relevant dimension-six operators ($O_{t \\varphi }, O_{\\varphi G}, O_{tG}$) of the standard model effective field theory. These operators also contribute to the production of Higgs bosons in loop-induced processes at the LHC, such as inclusive Higgs, $Hj$ and $HH$ production, and modify the Higgs decay branching ratios for which we also provide predictions. We perform a detailed study of the cross sections and their uncertainties at the total as well as differential level and of the structure of the effective field theory at NLO including renormalisation group effects. Finally, we show how the combination of information coming from measurements of these production processes will allow to constrain the three operators at the current and future LHC runs. Our results lead to a significant improvement of the ac...

  4. Novel synthetic ester of Brassicasterol, DFT investigation including NBO, NLO response, reactivity descriptor and its intramolecular interactions analyzed by AIM theory

    Science.gov (United States)

    Sethi, Arun; Prakash, Rohit

    2015-03-01

    In the present work, Brassicasterol (compound 1) isolated from Allamanda Violacea reacted with the well known NSAID ibuprofen by Steglich esterification yielding a novel steroidal ester, 3β-(2-(4-isobutyl phenyl) propionoxy) 24 methyl cholest-5, 22-dien (compound 2). Identity of synthetic derivative (compound 2) was done with the help of modern spectroscopic techniques like, 1H NMR, IR and UV as well as mass spectrometry. Molecular geometry and vibrational frequencies of compound 2 were calculated using density functional method (DFT/B3LYP) and 6-31(d,p) basis set. NMR chemical shifts of the compound were calculated with GIAO method. Electronic properties such as HOMO-LUMO energies were measured with the help of time dependent DFT method. Natural bond orbital (NBO) analysis was carried out to study hyperconjugative interactions. Non linear optical (NLO) response of compound 2 was also evaluated. Molecular electrostatic potential (MEP) surface has been used to indicate nucleophilic and electrophilic sites. Global reactivity descriptors of compound 1 and 2 were also calculated. Intramolecular interactions were analyzed using Atoms in molecule (AIM) theory.

  5. Structure, crystal growth, optical and mechanical studies of poly bis (thiourea) silver (I) nitrate single crystal: A new semi organic NLO material

    Science.gov (United States)

    Sivakumar, N.; Kanagathara, N.; Varghese, B.; Bhagavannarayana, G.; Gunasekaran, S.; Anbalagan, G.

    2014-01-01

    A new semi organic non linear optical polymeric crystal, bis (thiourea) silver (I) nitrate (TuAgN) with dimension 8 × 7 × 1.5 mm3 has been successfully grown from aqueous solution by slow evaporation solution technique. Single crystal X-ray diffraction study reveals that the crystal belongs to orthorhombic system with non centrosymmetric space group C2221. The crystalline perfection of the crystal was analyzed by high resolution X-ray diffraction (HRXRD) rocking curve measurements. Functional groups present in the crystal were analyzed qualitatively by infrared and Confocal Raman spectral analysis. Effects due to coordination of thiourea with metal ions were also discussed. Optical absorption study on TuAgN crystal shows the minimum absorption in the entire UV-Vis region and the lower cut off wavelength of TuAgN is found to be 318 nm. Thermal analysis shows that the material is thermally stable up to 180 °C. The mechanical strength and its parameters of the grown crystal were estimated by Vicker's microhardness test. The second harmonic generation (SHG) efficiency of the crystal was measured by Kurtz's powder technique infers that the crystal has nonlinear optical (NLO) efficiency 0.85 times that of KDP.

  6. Molecular structure, vibrational spectra, NLO and MEP analysis of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II).

    Science.gov (United States)

    Tanak, Hasan; Toy, Mehmet

    2013-11-01

    The molecular geometry and vibrational frequencies of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II) in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-311G(d,p) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The energetic and atomic charge behavior of the title compound in solvent media has been examined by applying the Onsager and the polarizable continuum model. To investigate second order nonlinear optical properties of the title compound, the electric dipole (μ), linear polarizability (α) and first-order hyperpolarizability (β) were computed using the density functional B3LYP and CAM-B3LYP methods with the 6-31+G(d) basis set. According to our calculations, the title compound exhibits nonzero (β) value revealing second order NLO behavior. In addition, DFT calculations of the title compound, molecular electrostatic potential (MEP), frontier molecular orbitals, and thermodynamic properties were performed at B3LYP/6-311G(d,p) level of theory. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Molecular structure, vibrational spectra, NLO and MEP analysis of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II)

    Science.gov (United States)

    Tanak, Hasan; Toy, Mehmet

    2013-11-01

    The molecular geometry and vibrational frequencies of bis[2-hydroxy-кO-N-(2-pyridyl)-1-naphthaldiminato-кN]zinc(II) in the ground state have been calculated by using the Hartree-Fock (HF) and density functional method (B3LYP) with 6-311G(d,p) basis set. The results of the optimized molecular structure are presented and compared with the experimental X-ray diffraction. The energetic and atomic charge behavior of the title compound in solvent media has been examined by applying the Onsager and the polarizable continuum model. To investigate second order nonlinear optical properties of the title compound, the electric dipole (μ), linear polarizability (α) and first-order hyperpolarizability (β) were computed using the density functional B3LYP and CAM-B3LYP methods with the 6-31+G(d) basis set. According to our calculations, the title compound exhibits nonzero (β) value revealing second order NLO behavior. In addition, DFT calculations of the title compound, molecular electrostatic potential (MEP), frontier molecular orbitals, and thermodynamic properties were performed at B3LYP/6-311G(d,p) level of theory.

  8. Measurement of D sup * meson cross sections at HERA and determination of the gluon density in the proton using NLO QCD

    CERN Document Server

    Adloff, C; Andreev, V; Andrieu, B; Arkadov, V; Arndt, C; Ayyaz, I; Babaev, A; Bähr, J; Baranov, P; Barrelet, E; Bartel, Wulfrin; Bassler, U; Bate, P; Beck, M; Beglarian, A; Behnke, O; Behrend, H J; Beier, C; Belousov, A; Berger, C; Bernardi, G; Bertrand-Coremans, G; Biddulph, P; Bizot, J C; Boudry, V; Braunschweig, W; Brisson, V; Brown, D P; Brückner, W; Bruel, P; Bruncko, Dusan; Bürger, J; Büsser, F W; Buniatian, A; Burke, S; Burrage, A; Buschhorn, G; Calvet, D; Campbell, A J; Carli, T; Chabert, E; Charlet, M; Clarke, D; Clerbaux, B; Contreras, J G; Cormack, C; Coughlan, J A; Cousinou, M C; Cox, B E; Cozzika, G; Cvach, J; Dainton, J B; Dau, W D; Daum, K; David, M; Davidsson, M; de Roeck, A; De Wolf, E A; Delcourt, B; Demirchyan, R; Diaconu, C; Dirkmann, M; Dixon, P; Dlugosz, W; Donovan, K T; Dowell, John D; Droutskoi, A; Ebert, J; Eckerlin, G; Eckstein, D; Efremenko, V; Egli, S; Eichler, R; Eisele, F; Eisenhandler, E F; Elsen, E; Enzensberger, H M; Erdmann, M; Fahr, A B; Favart, L; Fedotov, A; Felst, R; Feltesse, J; Ferencei, J; Ferrarotto, F; Fleischer, M; Flügge, G; Fomenko, A; Formánek, J; Foster, J M; Franke, G; Gabathuler, Erwin; Gabathuler, K; Gaede, F; Garvey, J; Gassner, J; Gayler, J; Gerhards, R; Ghazaryan, S; Glazov, A; Görlich, L; Gogitidze, N; Goldberg, M; Gorelov, I; Grab, C; Grässler, Herbert; Greenshaw, T; Griffiths, R K; Grindhammer, G; Hadig, T; Haidt, Dieter; Hajduk, L; Haller, T; Hampel, M; Haustein, V; Haynes, W J; Heinemann, B; Heinzelmann, G; Henderson, R C W; Hengstmann, S; Henschel, H; Heremans, R; Herynek, I; Hewitt, K; Hiller, K H; Hilton, C D; Hladky, J; Hoffmann, D; Horisberger, R P; Hurling, S; Ibbotson, M; Issever, C; Jacquet, M; Jaffré, M; Jansen, D M; Jönsson, L B; Johnson, D P; Jones, M; Jung, H; Kaestli, H K; Kander, M; Kant, D; Kapichine, M; Karlsson, M; Karschnik, O; Katzy, J; Kaufmann, O; Kausch, M; Kenyon, I R; Kermiche, S; Keuker, C; Kiesling, C; Klein, M; Kleinwort, C; Knies, G; Köhne, J H; Kolanoski, H; Kolya, S D; Korbel, V; Kostka, P; Kotelnikov, S K; Kraemerkaemper, T; Krasny, M W; Krehbiel, H; Krücker, D; Krüger, K; Küpper, A; Küster, H; Kuhlen, M; Kurca, T; Lahmann, R; Landon, M P J; Lange, W; Langenegger, U; Lebedev, A; Lehner, F; Lemaître, V; Lendermann, V; Levonian, S; Lindstrøm, M; List, B; Lobo, G; Lobodzinska, E; Lubimov, V; Lüders, S; Lüke, D; Lytkin, L; Magnussen, N; Mahlke-Krüger, H; Malinovskii, E I; Maracek, R; Marage, P; Marks, J; Marshall, R; Martin, G; Martyn, H U; Martyniak, J; Maxfield, S J; McMahon, T R; Mehta, A; Meier, K; Merkel, P; Metlica, F; Meyer, A; Meyer, A; Meyer, H; Meyer, J; Meyer, P O; Mikocki, S; Milstead, D; Moeck, J; Mohr, R F; Mohrdieck, S; Moreau, F; Morris, J V; Müller, D; Müller, K; Murín, P; Nagovizin, V; Naroska, Beate; Naumann, T; Negri, I; Newman, P R; Nguyen, H K; Nicholls, T C; Niebergall, F; Niebuhr, C B; Niedzballa, C; Niggli, H; Nikitin, D K; Nix, O; Nowak, G; Nunnemann, T; Oberlack, H; Olsson, J E; Ozerov, D; Palmen, P; Panassik, V; Pascaud, C; Passaggio, S; Patel, G D; Pawletta, H; Pérez, E; Phillips, J P; Pieuchot, A; Pitzl, D; Pöschl, R; Pope, G; Povh, B; Rabbertz, K; Rauschenberger, J; Reimer, P; Reisert, B; Reyna, D; Rick, H; Riess, S; Rizvi, E; Robmann, P; Roosen, R; Rosenbauer, K; Rostovtsev, A A; Rouse, F; Royon, C; Rusakov, S V; Rybicki, K; Sankey, D P C; Schacht, P; Scheins, J; Schilling, F P; Schleif, S; Schleper, P; Schmidt, D; Schmidt, D; Schoeffel, L; Schröder, V; Schultz-Coulon, H C; Schwab, B; Sefkow, F; Semenov, A; Shekelyan, V; Shevyakov, I; Shtarkov, L N; Siegmon, G; Sirois, Y; Sloan, T; Smirnov, P; Smith, M; Solochenko, V; Soloviev, Yu V; Spaskov, V; Specka, A; Spiekermann, J; Spitzer, H; Squinabol, F; Steffen, P; Steinberg, R; Steinhart, J; Stella, B; Stellberger, A; Stiewe, J; Straumann, U; Struczinski, W; Sutton, J P; Swart, M; Tapprogge, Stefan; Tasevsky, M; Tchernov, V V; Chechelnitskii, S; Theissen, J; Thompson, G; Thompson, P D; Tobien, N; Todenhagen, R; Truöl, P; Tsipolitis, G; Turnau, J; Tzamariudaki, E; Udluft, S; Usik, A; Valkár, S; Valkárová, A; Vallée, C; Van Esch, P; Van Haecke, A; Van Mechelen, P; Vazdik, Ya A; Villet, G; Wacker, K; Wallny, R; Walter, T; Waugh, B; Weber, G; Weber, M; Wegener, D; Wegner, A; Wengler, T; Werner, M; West, L R; Wiesand, S; Wilksen, T; Willard, S; Winde, M; Winter, G G; Wittek, C; Wittmann, E; Wobisch, M; Wollatz, H; Wünsch, E; Zácek, J; Zaleisak, J; Zhang, Z; Zhokin, A; Zini, P; Zomer, F; Zsembery, J; Zurnedden, M

    1999-01-01

    With the H1 detector at the ep collider HERA, D sup * meson production cross sections have been measured in deep inelastic scattering with four-momentum transfers Q sup 2 > 3 GeV sup 2 and in photoproduction at energies around W subgamma sub p approx 88 GeV and 194 GeV. Next-to-Leading Order QCD calculations are found to describe the differential cross sections within theoretical and experimental uncertainties. Using these calculations, the NLO gluon momentum distribution in the proton, x sub g g(x sub g), has been extracted in the momentum fraction range 7.5 x 10 sup - sup 4 < x sub g < 4 x 10 sup - sup 2 at average scales mu sup 2 = 25 to 50 GeV sup 2. The gluon momentum fraction x sub g has been obtained from the measured kinematics of the scattered electron and the D sup * meson in the final state. The results compare well with the gluon distribution obtained from the analysis of scaling violations of the proton structure function F sub 2.

  9. Numerical Solution of the Evolution Equation for Orbital Angular Momentum of Partons in the Nucleon

    CERN Document Server

    Martin, O; Schäfer, A

    1999-01-01

    The evolution of orbital angular momentum distributions within the radiative parton model is studied. We use different scenarios for the helicity weighted parton distributions and consider a broad range of input distributions for orbital angular momentum. In all cases we are lead to the conclusion that the absolute value of the average angular momentum per parton peaks at relatively large $x\\approx 0.1$ for perturbatively accessible scales. Furthermore, in all scenarios considered here the average orbital angular momentum per parton is several times larger for gluons than for quarks which favours gluon initiated reactions to measure orbital angular momentum. The large gluon polarization typically obtained in NLO-fits to DIS data is primarily canceled by the gluon orbital angular momentum.

  10. Laplace method for the evolution of the fragmentation function of Bc mesons

    Science.gov (United States)

    Boroun, G. R.; Zarrin, S.; Dadfar, S.

    2016-09-01

    In high-energy processes, the predominant mechanism for b bar c bound states is the production of a high-energy b bar or c quark, which fragments into the b bar c state. An approximate approach for the evolution of the fragmentation functions for the production of the S-wave states of Bc and Bc* is presented using Laplace transform technique in the leading order (LO) and next-to-leading order (NLO) analyses. The cross sections, as a function of the transverse momentum for the direct hadro-production b bar (c) →Bc and b bar (c) →Bc* based on the nonrelativistic quantum chromodynamics (QCD) factorization, are determined and compared with the Large Hadron Collider (LHC) and Tevatron data at the 1S-wave state.

  11. Evolution of nonlinear optical properties: from gold atomic clusters to plasmonic nanocrystals.

    Science.gov (United States)

    Philip, Reji; Chantharasupawong, Panit; Qian, Huifeng; Jin, Rongchao; Thomas, Jayan

    2012-09-12

    Atomic clusters of metals are an emerging class of extremely interesting materials occupying the intermediate size regime between atoms and nanoparticles. Here we report the nonlinear optical (NLO) characteristics of ultrasmall, atomically precise clusters of gold, which are smaller than the critical size for electronic energy quantization (∼2 nm). Our studies reveal remarkable features of the distinct evolution of the optical nonlinearity as the clusters progress in size from the nonplasmonic regime to the plasmonic regime. We ascertain that the smallest atomic clusters do not show saturable absorption at the surface plasmon wavelength of larger gold nanocrystals (>2 nm). Consequently, the third-order optical nonlinearity in these ultrasmall gold clusters exhibits a significantly lower threshold for optical power limiting. This limiting efficiency, which is superior to that of plasmonic nanocrystals, is highly beneficial for optical limiting applications.

  12. Galaxy Evolution

    Science.gov (United States)

    Matteucci, F.

    We review both the observational and theoretical constraints on the evolution of the abundances of heavy elements in gas and stars in galaxies of different morphological type. The main aim of this work is to document the progress made in our understanding of the physical processes regulating the chemical evolution of galaxies during the last sixteen years since the appearance, in this same journal (volume 5, page 287), of the well know review of Beatrice Tinsley, to whom I dedicate this paper. Finally, this article is addressed particularly to readers who do not actively work on galactic chemical evolution and who might use it as a cook book where the main ingredients are discussed and useful recipes can be found.

  13. Nonlinear Effects in Gluon Distribution Predicted by GLR-MQ Evolution Equation at Next-to-leading Order in LHC Data

    Science.gov (United States)

    Lalung, M.; Phukan, P.; Sarma, J. K.

    2017-09-01

    In this work we have solved the nonlinear GLR-MQ evolution equation upto next-to-leading order (NLO) by considering NLO terms of the gluon-gluon splitting functions and running coupling constant α s (Q 2). Here, we have incorporated a Regge-like behaviour of gluon distribution in order to obtain a solution of the GLR-MQ equation in the range of 5G e V 2 ≤ Q 2 ≤ 25G e V 2. We have studied the Q 2 evolution of the gluon distribution function G(x, Q 2) and its nonlinear effects at small-x. It can be observed from our analysis that the nonlinearities increase with decrease in the correlation radius R of two interacting gluons, as expected. We have compared our result of G(x, Q 2) as Q 2 increases and x decreases, for two different values of R, viz. R = 2G e V -1 and 5 G e V -1. We have also checked the sensitivity of the Regge intercept λ G on our results. We compare our computed results with those obtained by the global analysis to parton distribution functions (PDFs) by various collaborations where LHC data have been included viz. ABM12, CT14, MMHT14, PDF4LHC15, NNPDF3.0 and CJ15. Besides we have also shown comparison of our results with HERA PDF data viz. HERAPDF15.

  14. Animal evolution

    DEFF Research Database (Denmark)

    Nielsen, Claus

    This book provides a comprehensive analysis of evolution in the animal kingdom. It reviews the classical, morphological information from structure and embryology, as well as the new data gained from studies using immune stainings of nerves and muscles and blastomere markings, which makes...

  15. Representing Evolution

    DEFF Research Database (Denmark)

    Hedin, Gry

    2012-01-01

    . This article discusses Willumsen's etching in the context of evolutionary theory, arguing that Willumsen is a rare example of an artist who not only let the theory of evolution fuel his artistic imagination, but also concerned himself with a core issue of the theory, namely to what extent it could be applied...

  16. An extensive investigation on nucleation, growth parameters, crystalline perfection, spectroscopy, thermal, optical, microhardness, dielectric and SHG studies on potential NLO crystal - Ammonium Hydrogen L-tartarte

    Science.gov (United States)

    Hanumantharao, Redrothu; Kalainathan, S.; Bhagavannarayana, G.; Madhusoodanan, U.

    2013-02-01

    Ammonium Hydrogen L-tartarte (AMT), an organic nonlinear optical crystal was grown by slow evaporation method at ambient temperature. Solubility, metastable zone width and induction period of Ammonium Hydrogen L-tartarte in aqueous solution were determined. Good quality crystals were selected and characterized by Single crystal XRD, HR-XRD, FT-IR, 1H NMR, Mass, TGA-DTA, SEM, EDAX, optical and NLO studies. Single crystal XRD analysis revealed that the crystal system belongs to orthorhombic with cell parameters a = 7.65 Å, b = 7.85 Å and c = 11.07 Å. High-resolution-X-ray diffraction (HR-XRD) analysis was carried out to study the crystalline perfection of the grown crystal. 1H NMR and FTIR spectrum thus confirmed the presence of functional groups of the grown crystal. Molecular mass of AMT was measured accurately by mass spectroscopic analysis. Surface features of the grown crystal were analyzed by SEM, AFM, chemical etching and the presence of elements in the compound was identified by EDAX analysis. Thermal behavior of the grown crystal has been studied by TG/DTA analysis. The recorded UV-Vis-NIR spectrum shows excellent transmission in the region of 190-1100 nm. The Vickers and Knoop's microhardness studies have been carried out on AMT crystals over a range of 10-50 g. Hardness anisotropy has been observed in accordance with the orientation of the crystal. Fluorescence spectral studies were carried in the range of 280-500 nm for the grown crystal. The SHG conversion efficiency and laser damage threshold were measured using an Nd: YAG laser (1064 nm).

  17. DFT and ab initio study on non-linear optical (NLO) properties of some organic complexes with different conjugate linker and substituent groups

    Science.gov (United States)

    Tang, Guodong; Zhao, Jianying; Jiang, Zhengjing; Kou, Shanshan; Ju, Xuehai; Wei, Changmei

    2012-09-01

    A series of Schiff-bases chromophores containing imine or double C=C bond linkers between the donor and acceptor have been studied by first-principles calculations. The molecular structures, electronic properties and second order nonlinearities were investigated by DFT and ab initio methods. The optimized structural parameters of these Schiff-base derivates showed that these compounds are stable. The results of TD-DFT calculations indicate that the derivatives with the heterocyclic and imine linker have a red shift absorption compared to derivatives with the double C=C or N=N bonds. The analysis of the frontier molecular orbitals indicates that the CN group and the heterocycle linked by the CN or imine group has contribution to the LUMO orbital while the groups N(CH3)2 and the benzene ring linked by the double C=C or N=N bond have contribution to the HOMO orbital. The CN and the heterocyclic acceptors enable the derivatives to have a larger first static hyperpolarizability. However, the compounds 3-{4-[(4-Dimethylamino-phenylimino)-methyl]-pyridin-1-yl}-propanel-1-sulfonoperoxoic acid and 3-{4-[(4-Dimethylamino-phenylimino)-methyl]-quinolin-1-yl}propanel-1-sulfonoperoxoic acid with a substituent also have large first static hyperpolarizabilities due to the overwhelming contributions of electron density of the group to the HOMO orbital, that is, the HOMO orbital were constituted by the SO{3/-} group only. In order to understand the influence of the energy gap (Δ E) between the HOMO and the LUMO orbitals on the first static hyperpolarizability, we calculated the energy gap (Δ E) of all Schiff-base compounds. The results show that the smaller the HOMO-LUMO energy gap the larger the first static hyperpolarizability. The present study demonstrated that these compounds which have pure C=N double bond and heterocyclic substitution groups may have potential applications in the development of NLO materials.

  18. The spectroscopic (FT-IR, UV-vis), Fukui function, NLO, NBO, NPA and tautomerism effect analysis of (E)-2-[(2-hydroxy-6-methoxybenzylidene)amino]benzonitrile.

    Science.gov (United States)

    Demircioğlu, Zeynep; Kaştaş, Çiğdem Albayrak; Büyükgüngör, Orhan

    2015-03-15

    A new o-hydroxy Schiff base, (E)-2-[(2-hydroxy-6-methoxybenzylidene)amino]benzonitrile was isolated and investigated by experimental and theoretical methodologies. The solid state molecular structure was determined by X-ray diffraction method. The vibrational spectral analysis was carried out by using FT-IR spectroscopy in the range of 4000-400cm(-)(1). Theoretical calculations were performed by density functional theory (DFT) method using 6-31G(d,p) basis set. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The UV-vis spectrum of the compound was recorded in the region 200-800 nm in several solvents and electronic properties such as excitation energies, and wavelengths were calculated by TD-DFT/B3LYP method. The most prominent transitions were corresponds to π→π∗. Hybrid density functional theory (DFT) was used to investigate the enol-imine and keto-amine tautomers of titled compound. The titled compound showed the preference of enol form, as supported by X-ray and spectroscopic analysis results. The geometric and molecular properties were compaired for both enol-imine and keto-amine forms. Additionally, geometry optimizations in solvent media were performed with the same level of theory by the integral equation formalism polarizable continuum (IEF-PCM). Stability of the molecule arises from hyperconjugative interactions, charge delocalization and intramolecular hydrogen bond has been analyzed using natural bond orbital (NBO) analysis. Mulliken population method and natural population analysis (NPA) have been studied. Also, condensed Fukui function and relative nucleophilicity indices calculated from charges obtained with orbital charge calculation methods (NPA). Molecular electrostatic potential (MEP) and non linear optical (NLO) properties are also examined.

  19. Jet substructure using semi-inclusive jet functions in SCET

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Zhong-Bo [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States); Department of Physics and Astronomy, University of California,Los Angeles, CA 90095 (United States); Ringer, Felix; Vitev, Ivan [Theoretical Division, Los Alamos National Laboratory,Los Alamos, NM 87545 (United States)

    2016-11-25

    We propose a new method to evaluate jet substructure observables in inclusive jet measurements, based upon semi-inclusive jet functions in the framework of Soft Collinear Effective Theory (SCET). As a first example, we consider the jet fragmentation function, where a hadron h is identified inside a fully reconstructed jet. We introduce a new semi-inclusive fragmenting jet function G{sub i}{sup h}(z=ω{sub J}/ω,z{sub h}=ω{sub h}/ω{sub J},ω{sub J},R,μ), which depends on the jet radius R and the large light-cone momenta of the parton ‘i’ initiating the jet (ω), the jet (ω{sub J}), and the hadron h (ω{sub h}). The jet fragmentation function can then be expressed as a semi-inclusive observable, in the spirit of actual experimental measurements, rather than as an exclusive one. We demonstrate the consistency of the effective field theory treatment and standard perturbative QCD calculations of this observable at next-to-leading order (NLO). The renormalization group (RG) equation for the semi-inclusive fragmenting jet function G{sub i}{sup h}(z,z{sub h},ω{sub J},R,μ) are also derived and shown to follow exactly the usual timelike DGLAP evolution equations for fragmentation functions. The newly obtained RG equations can be used to perform the resummation of single logarithms of the jet radius parameter R up to next-to-leading logarithmic (NLL{sub R}) accuracy. In combination with the fixed NLO calculation, we obtain NLO+NLL{sub R} results for the hadron distribution inside the jet. We present numerical results for pp→(jet h)X in the new framework, and find excellent agreement with existing LHC experimental data.

  20. Representing Evolution

    DEFF Research Database (Denmark)

    Hedin, Gry

    2012-01-01

    A scandal shook Danish art when Jens Ferdinand Willumsen exhibited his etching Fertility in 1891. A heavily pregnant woman—Willumsen's wife, Juliette—and a short text about a new language of art flank a grain, which sprouts in a way that looks less like a plant than some sort of diagram....... This article discusses Willumsen's etching in the context of evolutionary theory, arguing that Willumsen is a rare example of an artist who not only let the theory of evolution fuel his artistic imagination, but also concerned himself with a core issue of the theory, namely to what extent it could be applied...

  1. Proton structure functions at HERA

    Science.gov (United States)

    Stella, Bruno

    2001-10-01

    The electron-proton collider HERA, like an electron-mycroscope, explores the structure of the proton down to 10-16 cm and up to the situation of very high parton densities. The proton energy was upgraded from 820 to 920 GeV in the Fall of '98 and the luminosity has also substantially improved, with another factor of 3 upgrade expected to follow this year. Inclusive proton structure functions have been studied with incident e+ and e- of 27 GeV in the neutral (NC) and charged (CC) current interactions as functions of the squared four-momentum transfer, Q2, and of the fractional proton momentum carried by partons, x. The structure function F2, as well as the γ-Z0 interference term xF3, have been measured in a range of Q2 and 1/x that extends by orders of magnitude that reached by fixed target experiments. The DGLAP evolution equations [1] allow for a perturbative NLO QCD fit of the measured non-perturbative structure functions in the available kinematic range: αS and the gluon density at low x are fitted at the same time with good precision. The longitudinal structure function, FL, can be determined within the DGLAP formalism. With CC, the electroweak unification has been tested; at high x, a first flavor decomposition of the light quarks is achieved. The contribution to F2 of the charm quark has been measured and results to be relevant. Bounds on the radius of quarks and on compositeness are derived from the data at the highest Q2, 100

  2. CHEMICAL EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Melvin

    1965-06-01

    How did life come to be on the surface of the earth? Darwin himself recognized that his basic idea of evolution by variation and natural selection must be a continuous process extending backward in time through that period in which the first living things arose and into the period of 'Chemical Evolution' which preceded it. We are approaching the examination of these events by two routes. One is to seek for evidence in the ancient rocks of the earth which were laid down prior to that time in which organisms capable of leaving their skeletons in the rocks to be fossilized were in existence. This period is sometime prior to approximately 600 million years ago. The earth is believed to have taken its present form approximately 4700 million years ago. We have found in rocks whose age is about 1000 million years certain organic molecules which are closely related to the green pigment of plants, chlorophyll. This seems to establish that green plants were already fluorishing prior to that time. We have now found in rocks of still greater age, namely, 2500 million years, the same kinds of molecules mentioned above which can be attributed to the presence of living organisms. If these molecules are as old as the rocks, we have thus shortened the time available for the generation of the complex biosynthetic sequences which give rise to these specific hydrocarbons (polyisoprenoids) to less than 2000 million years.

  3. Thought Evolution

    Directory of Open Access Journals (Sweden)

    Shadrikov V.D.

    2015-08-01

    Full Text Available The thought evolution is studied by historical reconstruction method that is based on the propositions of the theory of culturalhistorical determination of the psyche development, and the data of the morphological analysis and child development, and the conception of the psyche neuroontogenesis. The grounds for advisability of protothinking are presented. The protothinking is understood as the use of objective thought in cases of awareness absence. It is shown that protothinking is a form of transition from animal thinking to human speech. The particular attention is paid to the process of the word producing and thought generation in that process. The conditions of word producing as cooccurring acoustic pattern served for though expression are discussed. It is emphasized that a word is produced by a particular person. The historical development of the language and the specificity of this development are pointed out

  4. Community Evolution

    CERN Document Server

    Bródka, Piotr; Kazienko, Przemysław

    2016-01-01

    The continuous interest in the social network area contributes to the fast development of this field. The new possibilities of obtaining and storing data facilitate deeper analysis of the entire social network, extracted social groups and single individuals as well. One of the most interesting research topic is the network dynamics and dynamics of social groups in particular, it means analysis of group evolution over time. It is the natural step forward after social community extraction. Having communities extracted, appropriate knowledge and methods for dynamic analysis may be applied in order to identify changes as well as to predict the future of all or some selected groups. Furthermore, knowing the most probably change of a given group some additional steps may be performed in order to change this predicted future according to specific needs. Such ability would be a powerful tool in the hands of human resource managers, personnel recruitment, marketing, telecommunication companies, etc.

  5. Om religion og evolution

    DEFF Research Database (Denmark)

    Geertz, Armin W.

    2011-01-01

    for kulturens kausale virkning på den menneskelige kognition og ikke mindst den hominine evolution. Ud fra, hvad vi ved om den menneskelige evolution, ses det, at den hominine evolution har en dybde, som sjældent medtænkes i teorier og hypoteser om den menneskelige evolution. Den menneskelige evolution er...

  6. Groupware requirements evolution patterns

    NARCIS (Netherlands)

    Pumareja, Dulce Trinidad

    2013-01-01

    Requirements evolution is a generally known problem in software development. Requirements are known to change all throughout a system's lifecycle. Nevertheless, requirements evolution is a poorly understood phenomenon. Most studies on requirements evolution focus on changes to written specifications

  7. Has Human Evolution Stopped?

    OpenAIRE

    TEMPLETON, Alan R

    2010-01-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important ...

  8. Syntheses, crystal structures, and NLO properties of the quaternary sulfides RE{sub 3}Sb{sub 0.33}SiS{sub 7} (RE=La, Pr)

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hua-Jun, E-mail: cszzl772002@yeah.net [Laboratory of Applied Research on the Characteristic Resources in the North of Guizhou Province, School of Chemistry and Chemical Engineering, Zunyi Normal College, Zunyi, Guizhou 563002 (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

    2015-07-15

    Two quaternary sulfides RE{sub 3}Sb{sub 0.33}SiS{sub 7} (RE=La, Pr) have been prepared from stoichiometric mixtures of elements at 1223 K in an evacuated silica tube. They are the first examples of chalcogenides in the quaternary RE/Si/Sb/Q (RE=rare earth metal; Q=S, Se, Te) system. These two isostructural materials crystallize in the Ce{sub 3}Al{sub 1.67}S{sub 7} structure type in the hexagonal space group P6{sub 3}. Their structure features one-dimensional chains of face-sharing SbS{sub 6} octahedra running parallel to the c direction surrounded by the discrete SiS{sub 4} tetrahedra and RE cations. The La{sub 3}Sb{sub 0.33}SiS{sub 7} exhibits a SHG signal about 0.5 times that of the commercially used IR NLO material AgGaS{sub 2} at 2.05 μm laser. The optical gap of 1.92 eV for La{sub 3}Sb{sub 0.33}SiS{sub 7} was deduced from UV/Vis reflectance spectroscopy. - Graphical abstract: The RE{sub 3}Sb{sub 0.33}SiS{sub 7} (RE=La, Pr), crystalling in the Ce{sub 3}Al{sub 1.67}S{sub 7} structure type, have been prepared. The La{sub 3}Sb{sub 0.33}SiS{sub 7} exhibits a SHG signal about 0.5 times that of the IR NLO material AgGaS{sub 2}. - Highlights: • The RE{sub 3}Sb{sub 0.33}SiS{sub 7} (RE=La, Pr), crystalling in the Ce{sub 3}Al{sub 1.67}S{sub 7} structure type, have been prepared. • The La{sub 3}Sb{sub 0.33}SiS{sub 7} exhibits a SHG signal about 0.5 times that of the IR NLO material AgGaS{sub 2}. • The optical gap of 1.92 eV for La{sub 3}Sb{sub 0.33}SiS{sub 7} was deduced from UV/Vis reflectance spectroscopy.

  9. Nudging Evolution?

    Directory of Open Access Journals (Sweden)

    Katharine N. Farrell

    2013-12-01

    Full Text Available This Special Feature, "Nudging Evolution? Critical Exploration of the Potential and Limitations of the Concept of Institutional Fit for the Study and Adaptive Management of Social-Ecological Systems," aims to contribute toward the development of social theory and social research methods for the study of social-ecological system dynamics. Our objective is to help strengthen the academic discourse concerning if, and if so, how, to what extent, and in what concrete ways the concept of institutional "fit" might play a role in helping to develop better understanding of the social components of interlinkages between the socioeconomic-cultural and ecological dynamics of social-ecological systems. Two clearly discernible patterns provide a map of this Special Feature: (1 One pattern is the authors' positions regarding the place and role of normativity within their studies and assessment of institutional fit. Some place this at the center of their studies, exploring phenomena endogenous to the process of defining what constitutes institutional fit, whereas others take the formation of norms as a phenomenon exogenous to their study. (2 Another pattern is the type of studies presented: critiques and elaborations of the theory, methods for judging qualities of fit, and/or applied case studies using the concept. As a body of work, these contributions highlight that self-understanding of social-ecological place, whether explicit or implicit, constitutes an important part of the study object, i.e., the role of institutions in social-ecological systems, and that this is, at the same time, a crucial point of reference for the scholar wishing to evaluate what constitutes institutional fit and how it might be brought into being.

  10. QCD analysis of DIS structure functions in neutrino-nucleon scattering: Laplace transform and Jacobi polynomials approach

    CERN Document Server

    Nejad, S Mohammad Moosavi; Tehrani, S Atashbar; Mahdavi, Mahdi

    2016-01-01

    We present a detailed QCD analysis of nucleon structure functions $xF_3 (x, Q^2)$, based on Laplace transforms and Jacobi polynomials approach. The analysis corresponds to the next-to-leading order (NLO) and next-to-next-to-leading order (NNLO) approximation of perturbative QCD. The Laplace transform technique, as an exact analytical solution, is used for the solution of nonsinglet DGLAP evolution equations at low- and large-$x$ values. The extracted results are used as input to obtain the $x$ and Q$^2$ evolution of $xF_3(x, Q^2)$ structure functions using the Jacobi polynomials approach. In our work, the values of the typical QCD scale $\\Lambda_{\\overline{\\rm MS}}^{(n_f)}$ and the strong coupling constant $\\alpha_s(M_Z^2)$ are determined for four quark flavors ($n_f=4$) as well. A careful estimation of the uncertainties shall be performed using the Hessian method for the valence-quark distributions, originating from the experimental errors. We compare our valence-quark PDFs sets with those of other collabora...

  11. Evolution prediction from tomography

    Science.gov (United States)

    Dominy, Jason M.; Venuti, Lorenzo Campos; Shabani, Alireza; Lidar, Daniel A.

    2017-03-01

    Quantum process tomography provides a means of measuring the evolution operator for a system at a fixed measurement time t. The problem of using that tomographic snapshot to predict the evolution operator at other times is generally ill-posed since there are, in general, infinitely many distinct and compatible solutions. We describe the prediction, in some "maximal ignorance" sense, of the evolution of a quantum system based on knowledge only of the evolution operator for finitely many times 0evolution at times away from the measurement times. Even if the original evolution is unitary, the predicted evolution is described by a non-unitary, completely positive map.

  12. The Evolution of Design

    Science.gov (United States)

    Stebbins, G. Ledyard

    1973-01-01

    Describes the basic logic behind the modern view of evolution theory. Despite gaps in fossil records, evidence is indicative of the origin of life from nonliving molecules and evolution of higher forms of life from simpler forms. (PS)

  13. Cannabis: evolution and ethnobotany

    National Research Council Canada - National Science Library

    Clarke, Robert Connell; Merlin, Mark David

    2013-01-01

    "Cannabis: Evolution and Ethnobotany is a comprehensive, interdisciplinary exploration of the natural origins and early evolution of this famous plant, highlighting its historic role in the development of human societies...

  14. Mistakes and Molecular Evolution.

    Science.gov (United States)

    Trevors, J. T.

    1998-01-01

    Examines the role mistakes play in the molecular evolution of bacteria. Discusses the interacting physical, chemical, and biological factors that cause changes in DNA and play a role in prokaryotic evolution. (DDR)

  15. Evolution & Diversity in Plants.

    Science.gov (United States)

    Pearson, Lorentz C.

    1988-01-01

    Summarizes recent findings that help in understanding how evolution has brought about the diversity of plant life that presently exists. Discusses basic concepts of evolution, diversity and classification, the three-line hypothesis of plant evolution, the origin of fungi, and the geologic time table. Included are 31 references. (CW)

  16. The semi-inclusive jet function in SCET and small radius resummation for inclusive jet production

    CERN Document Server

    Kang, Zhong-Bo; Vitev, Ivan

    2016-01-01

    We introduce a new kind of jet function: the semi-inclusive jet function $J_i(z, \\omega_J, \\mu)$, which describes how a parton $i$ is transformed into a jet with a jet radius $R$ and energy fraction $z = \\omega_J/\\omega$, with $\\omega_J$ and $\\omega$ being the large light-cone momentum component of the jet and the corresponding parton $i$ that initiates the jet, respectively. Within Soft Collinear Effective Theory (SCET), we calculate both $J_q(z, \\omega_J, \\mu)$ and $J_g(z, \\omega_J, \\mu)$ to the next-to-leading order (NLO), and for both cone and anti-k$_{\\rm T}$ algorithms. We demonstrate that the renormalization group (RG) equations of $J_i(z, \\omega_J, \\mu)$ follow exactly the usual DGLAP evolution, which can be used to perform the $\\ln R$ resummation for {\\it inclusive} jet cross sections with a small jet radius $R$. We clarify the difference between our RG equations of $J_i(z, \\omega_J, \\mu)$ and those of so-called unmeasured jet functions $J_i(\\omega_J, \\mu)$, widely used in SCET for {\\it exclusive} je...

  17. Perturbative stability of the QCD predictions for the ratio $R=F_L/F_T$ and azimuthal asymmetry in heavy-quark leptoproduction

    CERN Document Server

    Ivanov, N Ya

    2012-01-01

    We analyze the perturbative and parametric stability of the QCD predictions for the Callan-Gross ratio $R(x,Q^2)=F_L/F_T$ and azimuthal $\\cos(2\\varphi)$ asymmetry in heavy-quark leptoproduction. Our analysis shows that large radiative corrections to the structure functions cancel each other in their ratio $R(x,Q^2)$ and azimuthal asymmetry with good accuracy. As a result, the NLO contributions to the Callan-Gross ratio and $\\cos(2\\varphi)$ asymmetry are less than 10% in a wide region of the variables $x$ and $Q^2$. We provide compact analytic predictions for $R(x,Q^2)$ and asymmetry in the case of low $x\\ll 1$. Simple formulae connecting the high-energy behavior of the Callan-Gross ratio and azimuthal asymmetry with the low-$x$ asymptotics of the gluon density in the target are derived. It is shown that the obtained hadron-level predictions for $R(x,Q^2)$ and azimuthal asymmetry are stable at $x\\ll 1$ under the DGLAP evolution of the gluon distribution function. Concerning the experimental aspects, we propose...

  18. New acceptor-bridge-donor strategy for enhancing NLO response with long-range excess electron transfer from the NH2...M/M3O donor (M = Li, Na, K) to inside the electron hole cage C20F19 acceptor through the unusual σ chain bridge (CH2)4.

    Science.gov (United States)

    Bai, Yang; Zhou, Zhong-Jun; Wang, Jia-Jun; Li, Ying; Wu, Di; Chen, Wei; Li, Zhi-Ru; Sun, Chia-Chung

    2013-04-01

    Using the strong electron hole cage C20F19 acceptor, the NH2...M/M3O (M = Li, Na, and K) complicated donors with excess electron, and the unusual σ chain (CH2)4 bridge, we construct a new kind of electride molecular salt e(-)@C20F19-(CH2)4-NH2...M(+)/M3O(+) (M = Li, Na, and K) with excess electron anion inside the hole cage (to be encapsulated excess electron-hole pair) serving as a new A-B-D strategy for enhancing nonlinear optical (NLO) response. An interesting push-pull mechanism of excess electron generation and its long-range transfer is exhibited. The excess electron is pushed out from the (super)alkali atom M/M3O by the lone pair of NH2 in the donor and further pulled inside the hole cage C20F19 acceptor through the efficient long σ chain (CH2)4 bridge. Owing to the long-range electron transfer, the new designed electride molecular salts with the excess electron-hole pair exhibit large NLO response. For the e(-)@C20F19-(CH2)4-NH2...Na(+), its large first hyperpolarizability (β0) reaches up to 9.5 × 10(6) au, which is about 2.4 × 10(4) times the 400 au for the relative e(-)@C20F20...Na(+) without the extended chain (CH2)4-NH2. It is shown that the new strategy is considerably efficient in enhancing the NLO response for the salts. In addition, the effects of different bridges and alkali atomic number on β0 are also exhibited. Further, three modulating factors are found for enhancing NLO response. They are the σ chain bridge, bridge-end group with lone pair, and (super)alkali atom. The new knowledge may be significant for designing new NLO materials and electronic devices with electrons inside the cages. They may also be the basis of establishing potential organic chemistry with electron-hole pair.

  19. Has Human Evolution Stopped?

    Directory of Open Access Journals (Sweden)

    Alan R. Templeton

    2010-07-01

    Full Text Available It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  20. Has human evolution stopped?

    Science.gov (United States)

    Templeton, Alan R

    2010-07-01

    It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important implications for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the human gene pool, thereby enhancing the potential for human evolution. The increase in human population size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual heterozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.

  1. Spectroscopic, DNA binding ability, biological activity, DFT calculations and non linear optical properties (NLO) of novel Co(II), Cu(II), Zn(II), Cd(II) and Hg(II) complexes with ONS Schiff base

    Science.gov (United States)

    Abdel Aziz, Ayman A.; Elantabli, Fatma M.; Moustafa, H.; El-Medani, Samir M.

    2017-08-01

    The reaction of Co(II), Cu(II), Zn(II), Cd(II) and Hg(II) with the synthesized N-(2-hydroxy-1-naphthylidene)-2-aminothiophenol Schiff base ligand (H2L) at room temperature resulted in the formation of the five complexes; [Co(HL)2]H2O, 1; [M(HL)2] (M = Cu, Zn and Cd), (2-4) and [Hg(HL)Cl], 5. The ligand and its complexes were characterized based on elemental analyses, IR, 1H NMR, magnetic measurement, molar conductance, and thermal analysis. Coats and Redfern method was used to compute the kinetic and thermodynamic parameters. Antimicrobial activities of H2L and its complexes have been studied. The binding of Co(II), Cu(II) and Zn(II) complexes to calf thymus DNA (CT-DNA) has been investigated using UV-Vis and fluorescence absorption spectra. The results indicated that the ligand and its complexes may bind to DNA by intercalation modes, with a much higher binding affinity of the complexes than that of the ligand. The equilibrium geometries of the studied complexes are investigated theoretically at the B3LYP/LANL2DZ level of theory, and it was found that these geometries are non-linear. The calculated EHOMO and ELUMO energies of the studied complexes can be used to calculate the global properties. The calculated nonlinear optical parameters (NLO); first order hyperpolarizibility (β) of the studied complexes show promising optical properties.

  2. Spectroscopic (FT-IR, FT-Raman, and UV-visible) and quantum chemical studies on molecular geometry, Frontier molecular orbitals, NBO, NLO and thermodynamic properties of 1-acetylindole.

    Science.gov (United States)

    Shukla, Vikas K; Al-Abdullah, Ebtehal S; El-Emam, Ali A; Sachan, Alok K; Pathak, Shilendra K; Kumar, Amarendra; Prasad, Onkar; Bishnoi, Abha; Sinha, Leena

    2014-12-10

    Quantum chemical calculations of ground state energy, geometrical structure and vibrational wavenumbers of 1-acetylindole were carried out using density functional (DFT/B3LYP) method with 6-311++G(d,p) basis set. The FT-IR and FT-Raman spectra were recorded in the condensed state. The fundamental vibrational wavenumbers were calculated and a good correlation between experimental and scaled calculated wavenumbers has been accomplished. Electric dipole moment, polarizability and first static hyperpolarizability values of 1-acetylindole have been calculated at the same level of theory and basis set. The results show that the 1-acetylindole molecule possesses nonlinear optical (NLO) behavior with non-zero values. Stability of the molecule arising from hyper-conjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. UV-Visible spectrum of the molecule was recorded in the region 200-500nm and the electronic properties like HOMO and LUMO energies and composition were obtained using TD-DFT method. The calculated energies and oscillator strengths are in good correspondence with the experimental data. The thermodynamic properties of the compound under investigation were calculated at different temperatures. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Vibrational analysis using FT-IR, FT-Raman spectra and HF-DFT methods and NBO, NLO, NMR, HOMO-LUMO, UV and electronic transitions studies on 2,2,4-trimethyl pentane

    Science.gov (United States)

    Suvitha, A.; Periandy, S.; Govindarajan, M.; Gayathri, P.

    2015-03-01

    In this work, the vibrational spectral analysis was carried out by using Raman and infrared spectroscopy in the range 100-4000 cm-1and 50-4000 cm-1, respectively, for 2,2,4-Trimethyl Pentane, TMP (C8H18) molecule. The molecular structure, fundamental vibrational frequencies and intensity of the vibrational bands are interpreted with the aid of structure optimizations and geometrical parameter calculations based on Hartree Fock (HF) and density functional theory (DFT) method with 6-311++G(d,p) basis set. The scaled B3LYP/6-311++G(d,p) results shows the best agreement with the experimental values over the other method. The calculated HOMO and LUMO energies shows that charge transfer within the molecule. The physical reactions of single bond hydrocarbon TMP were investigated. The results of the calculations were applied to simulate spectra of the title compound, which shows the excellent agreement with observed spectra. Besides, Mulliken atomic charges, UV, frontier molecular orbital (FMO), MEP, NLO activity, Natural Bond-Orbital (NBO) analysis, NMR and thermodynamic properties of title molecule were also performed.

  4. Vibrational spectroscopic studies, Fukui functions, HOMO-LUMO, NLO, NBO analysis and molecular docking study of (E)-1-(1,3-benzodioxol-5-yl)-4,4-dimethylpent-1-en-3-one, a potential precursor to bioactive agents

    Science.gov (United States)

    Al-Wabli, Reem I.; Resmi, K. S.; Sheena Mary, Y.; Yohannan Panicker, C.; Attia, Mohamed I.; El-Emam, Ali A.; Van Alsenoy, C.

    2016-11-01

    The FT-IR and FT-Raman spectra of (E)-1-(1,3-benzodioxol-5-yl)-4,4-dimethylpent-1-en-3-one were recorded and analyzed experimentally and theoretically. The observed experimental and theoretical wavenumbers were assigned using potential energy distribution. The NLO properties were evaluated by the determination of first and second hyperpolarizabilities of the title compound. From the frontier molecular orbital study, the HOMO centers over the entire molecule except the methyl groups, while the LUMO is over the entire molecule except the CH2 group with the dioxole ring and one of the methyl groups. From the MEP plot, it is evident that the negative region covers the carbonyl and Cdbnd C groups and the positive region is over CH2 groups. The Fukui functions are also reported. The calculated geometrical parameters are in agreement with the XRD results. From the molecular docking study, the docked ligand title compound forms a stable complex with the androgen receptor and gives a binding affinity value of -8.1 kcal/mol and the results suggest that the compound might exhibit inhibitory activity against androgen receptor.

  5. Structural, thermal, laser damage, photoconductivity, NLO and mechanical properties of modified vertical Bridgman method grown AgGa0.5In0.5Se2 single crystal

    Science.gov (United States)

    Vijayakumar, P.; Ramasamy, P.

    2016-08-01

    AgGa0.5In0.5Se2 single crystal was grown using modified vertical Bridgman method. The structural perfection of the AgGa0.5In0.5Se2 single crystal has been analyzed by high-resolution X-ray diffraction rocking curve measurements. The structural and compositional uniformities of AgGa0.5In0.5Se2 were studied using Raman scattering spectroscopy at room temperature. The FWHM of the Γ1 (W1) and Γ5L (Γ15) measured at different regions of the crystal confirms that the composition throughout its length is fairly uniform. Thermal properties of the as-grown crystal, including specific heat, thermal diffusivity and thermal conductivity have been investigated. The multiple shot surface laser damage threshold value was measured using Nd:YAG laser. Photoconductivity measurements with different temperatures have confirmed the positive photoconducting behavior. Second harmonic generation (SHG) on powder samples has been measured using the Kurtz and Perry technique and the results display that AgGa0.5In0.5Se2 is a phase-matchable NLO material. The hardness behavior has been measured using Vickers micro hardness measurement and the indentation size effect has been observed. The classical Meyer's law, propositional resistance model and modified propositional resistance model have been used to analyse the micro hardness behavior.

  6. A series of noncentrosymmetric antimony sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) - syntheses, crystal and electronic structures, and NLO properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hua-Jun [Laboratory of Applied Research on the Characteristic Resources in the North of Guizhou Province, School of Chemistry and Chemical Engineering, Zunyi Normal College, Guizhou (China); State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China); Zhou, Liu-Jiang [State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou (China)

    2015-02-15

    A series of noncentrosymmetric sulfides Ln{sub 8}Sb{sub 2}S{sub 15} (Ln = La, Pr, Nd) were prepared from stoichiometric mixtures of the elements at 1223 K in an evacuated silica tube. The compounds Ln{sub 8}Sb{sub 2}S{sub 15} with Ln = La and Nd are isostructural to Pr{sub 8}Sb{sub 2}S{sub 15} and crystallize in the tetragonal noncentrosymmetric space group I4{sub 1}cd. Their structure contains discrete [SbS{sub 3}]{sup 3-} trigonal pyramids separated by Ln{sup 3+} cations and S{sup 2-} anions. La{sub 8}Sb{sub 2}S{sub 15} shows second harmonic generation with intensities 1.2 times that of the commercially used IR NLO (nonlinear optics) material AgGaS{sub 2} (at 2.05 μm laser). It exhibits excellent thermal stability up to 663 C. Studies with UV/Vis-NIR diffuse reflectance spectroscopy show that La{sub 8}Sb{sub 2}S{sub 15} has an optical gap of around 2.3 eV, and a DFT study indicates a direct band gap with an electronic transfer excitation of S 3p electrons to a La 5d orbital. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Oxygen evolution reaction catalysis

    Science.gov (United States)

    Haber, Joel A.; Jin, Jian; Xiang, Chengxiang; Gregoire, John M.; Jones, Ryan J.; Guevarra, Dan W.; Shinde, Aniketa A.

    2016-09-06

    An Oxygen Evolution Reaction (OER) catalyst includes a metal oxide that includes oxygen, cerium, and one or more second metals. In some instances, the cerium is 10 to 80 molar % of the metals in the metal oxide and/or the catalyst includes two or more second metals. The OER catalyst can be included in or on an electrode. The electrode can be arranged in an oxygen evolution system such that the Oxygen Evolution Reaction occurs at the electrode.

  8. Evolution of biological complexity

    OpenAIRE

    Adami, Christoph; Ofria, Charles; Travis C. Collier

    2000-01-01

    In order to make a case for or against a trend in the evolution of complexity in biological evolution, complexity needs to be both rigorously defined and measurable. A recent information-theoretic (but intuitively evident) definition identifies genomic complexity with the amount of information a sequence stores about its environment. We investigate the evolution of genomic complexity in populations of digital organisms and monitor in detail the evolutionary transitions that increase complexit...

  9. Museums teach evolution.

    Science.gov (United States)

    Diamond, Judy; Evans, E Margaret

    2007-06-01

    Natural history museums play a significant role in educating the general public about evolution. This article describes Explore Evolution, one of the largest evolution education projects funded by the National Science Foundation. A group of regional museums from the Midwestern United States worked with leading evolutionary scientists to create multiple permanent exhibit galleries and a curriculum book for youth. This program invites the public to experience current evolutionary research on organisms that range in size from HIV to whales. Learning research is being conducted on museum visitors to understand how they reason about evolution and to determine what influences the process of conceptual change.

  10. Mueller-Navelet jets at LHC: BFKL versus high-energy DGLAP

    Energy Technology Data Exchange (ETDEWEB)

    Celiberto, F.G.; Murdaca, B.; Papa, A. [Dipartimento di Fisica, Universita della Calabria, Cosenza (Italy); Istituto Nazionale di Fisica Nucleare, Gruppo Collegato, Cosenza (Italy); Ivanov, D.Yu. [Sobolev Institute of Mathematics, Novosibirsk (Russian Federation); Novosibirsk State University, Novosibirsk (Russian Federation)

    2015-06-15

    The production of forward jets separated by a large rapidity gap at LHC, the so-called Mueller-Navelet jets, is a fundamental testfield for perturbative QCD in the high-energy limit. Several analyses have already provided us with evidence about the compatibility of theoretical predictions, based on collinear factorization and BFKL resummation of energy logarithms in the next-to-leading approximation, with the CMS experimental data at 7 TeV of center-of-mass energy. However, the question if the same data can be described also by fixed-order perturbative approaches has not yet been fully answered. In this paper we provide numerical evidence that the mere use of partially asymmetric cuts in the transverse momenta of the detected jets allows for a clear separation between BFKL-resummed and fixed-order predictions in some observables related with the Mueller-Navelet jet production process. (orig.)

  11. Evolution: functional evolution of nuclear structure.

    Science.gov (United States)

    Wilson, Katherine L; Dawson, Scott C

    2011-10-17

    The evolution of the nucleus, the defining feature of eukaryotic cells, was long shrouded in speculation and mystery. There is now strong evidence that nuclear pore complexes (NPCs) and nuclear membranes coevolved with the endomembrane system, and that the last eukaryotic common ancestor (LECA) had fully functional NPCs. Recent studies have identified many components of the nuclear envelope in living Opisthokonts, the eukaryotic supergroup that includes fungi and metazoan animals. These components include diverse chromatin-binding membrane proteins, and membrane proteins with adhesive lumenal domains that may have contributed to the evolution of nuclear membrane architecture. Further discoveries about the nucleoskeleton suggest that the evolution of nuclear structure was tightly coupled to genome partitioning during mitosis.

  12. Software evolution with XVCL

    DEFF Research Database (Denmark)

    Zhang, Weishan; Jarzabek, Stan; Zhang, Hongyu

    2004-01-01

    This chapter introduces software evolution with XVCL (XML-based Variant Configuration Language), which is an XML-based metaprogramming technique. As the software evolves, a large number of variants may arise, especially whtn such kinds of evolutions are related to multiple platforms as shown in o...

  13. Framing Evolution Discussion Intellectually

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin; Buck, Gayle A.

    2011-01-01

    This study examines how a first-year biology teacher facilitates a series of whole-class discussions about evolution during the implementation of a problem-based unit. A communicative theoretical perspective is adopted wherein evolution discussions are viewed as social events that the teacher can frame intellectually (i.e., present or organize as…

  14. Evolution for Young Victorians

    Science.gov (United States)

    Lightman, Bernard

    2012-01-01

    Evolution was a difficult topic to tackle when writing books for the young in the wake of the controversies over Darwin's "Origin of Species." Authors who wrote about evolution for the young experimented with different ways of making the complex concepts of evolutionary theory accessible and less controversial. Many authors depicted presented…

  15. Evolution of Constructivism

    Science.gov (United States)

    Liu, Chu Chih; Chen, I Ju

    2010-01-01

    The contrast between social constructivism and cognitive constructivism are depicted in different ways in many studies. The purpose of this paper is to summarize the evolution of constructivism and put a focus on social constructivism from the perception of Vygotsky. This study provides a general idea of the evolution of constructivism for people…

  16. Self and Evolution.

    Science.gov (United States)

    Csikszentmihalyi, Mihaly

    1998-01-01

    Suggests the time has come for humans to direct their own individual evolution and the evolution of the entire species. Argues that ways must be found to encourage individuals, families, and cultures to discover and develop their differentiating characteristics and help these groups integrate with other cultures, customs, and belief systems.…

  17. Thermodynamical Arguments against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-01-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be…

  18. Framing Evolution Discussion Intellectually

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin; Buck, Gayle A.

    2011-01-01

    This study examines how a first-year biology teacher facilitates a series of whole-class discussions about evolution during the implementation of a problem-based unit. A communicative theoretical perspective is adopted wherein evolution discussions are viewed as social events that the teacher can frame intellectually (i.e., present or organize as…

  19. Kognition, evolution og Bibel

    DEFF Research Database (Denmark)

    Jensen, Hans Jørgen Lundager

    2012-01-01

    En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)......En opfordring til, at Bibelvidneskaberne oprienterer sig i retning af aktuelle teorier om bio-kulturel evolution (Merlin Donald, aksetids-teori hos fx Robert Bellah)...

  20. Evolution for Young Victorians

    Science.gov (United States)

    Lightman, Bernard

    2012-01-01

    Evolution was a difficult topic to tackle when writing books for the young in the wake of the controversies over Darwin's "Origin of Species." Authors who wrote about evolution for the young experimented with different ways of making the complex concepts of evolutionary theory accessible and less controversial. Many authors depicted presented…

  1. Evolution's Erratic Pace

    Science.gov (United States)

    Gould, Stephen Jay

    1977-01-01

    Offers an opposing view to Darwin's statement that evolution occurs through gradual change, using fossil species and modes of evolution to lend support to the author's model of "punctuated equilibria," in which... "Lineages change little during most of their history, but events of rapid speciation occasionally punctuate this…

  2. Evolution Under Attack

    Science.gov (United States)

    Muench, David; Newell, Norman D.

    1974-01-01

    The article points out the growing attempts by creationists to have special creation presented with evolution in any educational discussion of the origin of life. The evolution theory is shown to be consistent with known scientific facts while the theory of special creation does not adequately account for these facts. (LS)

  3. Cultural Evolution and SETI

    Science.gov (United States)

    Dick, S. J.

    2009-12-01

    The Drake Equation for the number of radio communicative technological civilizations in the Galaxy encompasses three components of cosmic evolution: astronomical, biological and cultural. Of these three, cultural evolution totally dominates in terms of the rapidity of its effects. Yet, SETI scientists do not take cultural evolution into account, perhaps for understandable reasons, since cultural evolution is not well-understood even on Earth and is unpredictable in its outcome. But the one certainty for technical civilizations billions, millions, or even thousands of years older than ours is that they will have undergone cultural evolution. Cultural evolution potentially takes place in many directions, but this paper argues that its central driving force is the maintenance, improvement and perpetuation of knowledge and intelligence, and that to the extent intelligence can be improved, it will be improved. Applying this principle to life in the universe, extraterrestrials will have sought the best way to improve their intelligence. One possibility is that they may have long ago advanced beyond flesh-and-blood to artificial intelligence, constituting a postbiological universe. Although this subject has been broached, it has not been given the attention it is due from its foundation in cultural evolution. Nor has the idea of a postbiological universe been carried to its logical conclusion, including a careful analysis of the implications for SETI. SETI scientists, social scientists, and experts in AI should consider the strengths and weaknesses of this new paradigm.

  4. Dual phase evolution

    CERN Document Server

    Green, David G; Abbass, Hussein A

    2014-01-01

    This book explains how dual phase evolution operates in all these settings and provides a detailed treatment of the subject. The authors discuss the theoretical foundations for the theory, how it relates to other phase transition phenomena and its advantages in evolutionary computation and complex adaptive systems. The book provides methods and techniques to use this concept for problem solving. Dual phase evolution concerns systems that evolve via repeated phase shifts in the connectivity of their elements. It occurs in vast range of settings, including natural systems (species evolution, landscape ecology, geomorphology), socio-economic systems (social networks) and in artificial systems (annealing, evolutionary computing).

  5. Galactic Chemical Evolution

    CERN Document Server

    Mollá, M; da Costa, R; Gibson, B K; Díaz, A I

    2016-01-01

    We analyze the evolution of oxygen abundance radial gradients resulting from our chemical evolution models calculated with different prescriptions for the star formation rate (SFR) and for the gas infall rate, in order to assess their respective roles in shaping gradients. We also compare with cosmological simulations and confront all with recent observational datasets, in particular with abundances inferred from planetary nebulae. We demonstrate the critical importance in isolating the specific radial range over which a gradient is measured, in order for their temporal evolution to be useful indicators of disk growth with redshift.

  6. Evolution of science I: Evolution of Mind

    CERN Document Server

    Vahia, M N

    2016-01-01

    The central nervous system and particularly the brain was designed to control the life cycle of a living being. With increasing size and sophistication, in mammals, the brain became capable of exercising significant control over life. In Homo Sapiens the brain became significantly powerful and capable of comprehension beyond survival needs with visualisation, formal thought and long term memory. Here we trace the rise of the powers of the brains of the Homo Sapiens and its capability of three comprehending the three spatial dimensions as well as time. By tracing the evolution of technology over the last millennium and particularly the late arrival of astronomy to discuss the evolution of the formal thinking process in humans. In a follow up paper we will trace the extensive use of this new faculty by humans to comprehend the working of the universe.

  7. Comment on the paper "Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-chloro 4-nitrostilbene (CONS): a potential NLO material" by P.M. Dinakaran, S. Kalainathan [Spectrochim. Acta A 111 (2013) 123-130].

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R; Dhuri, Sunder N; Nadkarni, V S

    2014-01-03

    We argue that (trans)-4-chloro-4'-nitrostilbene is not a new organic nonlinear optical material as claimed by Dinakaran and Kalainathan [P.M. Dinakaran, S. Kalainathan, Synthesis, growth, structural, spectral, thermal, chemical etching, linear and nonlinear optical and mechanical studies of an organic single crystal 4-Chloro 4-Nitrostilbene (CONS): a potential NLO material, Spectrochim. Acta A 111 (2013) 123-130], but instead a well-known compound whose synthesis, spectral data, single crystal structure and second harmonic generation (SHG) efficiency are well documented in the literature. The title paper is completely erroneous. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Evolution of oncolytic viruses.

    Science.gov (United States)

    Sanjuán, Rafael; Grdzelishvili, Valery Z

    2015-08-01

    Owing to their replicative capacity, oncolytic viruses (OVs) can evolve under the action of natural selection. Reversion to virulence and recombination with wild-type strains may compromise OV safety, therefore requiring evolutionary risk assessment studies. On the other hand, evolution can be directed in the laboratory to create more potent and safer OVs. Previous work in the experimental evolution field provides a background for OV directed evolution, and has identified interesting exploitable features. While genetic engineering has greatly advanced the field of oncolytic virotherapy, this approach is sometimes curtailed by the complexity and diversity of virus-host interactions. Directed evolution provides an alternative approach that may help to obtain new OVs without prejudice toward the underlying molecular mechanisms involved. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Evolution, epigenetics and cooperation

    Indian Academy of Sciences (India)

    Patrick Bateson

    2014-04-01

    Explanations for biological evolution in terms of changes in gene frequencies refer to outcomes rather than process. Integrating epigenetic studies with older evolutionary theories has drawn attention to the ways in which evolution occurs. Adaptation at the level of the gene is givingway to adaptation at the level of the organism and higher-order assemblages of organisms. These ideas impact on the theories of how cooperation might have evolved. Two of the theories, i.e. that cooperating individuals are genetically related or that they cooperate for self-interested reasons, have been accepted for a long time. The idea that adaptation takes place at the level of groups is much more controversial. However, bringing together studies of development with those of evolution is taking away much of the heat in the debate about the evolution of group behaviour.

  10. Galactic Chemical Evolution

    National Research Council Canada - National Science Library

    Gibson, Brad K; Fenner, Yeshe; Renda, Agostino; Kawata, Daisuke; Lee, Hyun-chul

    2003-01-01

    .... We review the current state-of-the-art semi-analytical and chemodynamical models for the Milky Way, emphasising the strengths and weaknesses of both approaches. Keywords: Galaxy: abundances — Galaxy: evolution — Galaxy: formation — Galaxy...

  11. Evolution, epigenetics and cooperation.

    Science.gov (United States)

    Bateson, Patrick

    2014-04-01

    Explanations for biological evolution in terms of changes in gene frequencies refer to outcomes rather than process. Integrating epigenetic studies with older evolutionary theories has drawn attention to the ways in which evolution occurs. Adaptation at the level of the gene is givingway to adaptation at the level of the organism and higher-order assemblages of organisms. These ideas impact on the theories of how cooperation might have evolved. Two of the theories, i.e. that cooperating individuals are genetically related or that they cooperate for self-interested reasons, have been accepted for a long time. The idea that adaptation takes place at the level of groups is much more controversial. However, bringing together studies of development with those of evolution is taking away much of the heat in the debate about the evolution of group behaviour.

  12. Chemical evolution and life

    Directory of Open Access Journals (Sweden)

    Malaterre Christophe

    2015-01-01

    Full Text Available In research on the origins of life, the concept of “chemical evolution” aims at explaining the transition from non-living matter to living matter. There is however strong disagreement when it comes to defining this concept more precisely, and in particular with reference to a chemical form of Darwinian evolution: for some, chemical evolution is nothing but Darwinian evolution applied to chemical systems before life appeared; yet, for others, it is the type of evolution that happened before natural selection took place, the latter being the birthmark of living systems. In this contribution, I review the arguments defended by each side and show how both views presuppose a dichotomous definition of “life”.

  13. Manipulation of quantum evolution

    Science.gov (United States)

    Cabera, David Jose Fernandez; Mielnik, Bogdan

    1994-01-01

    The free evolution of a non-relativistic charged particle is manipulated using time-dependent magnetic fields. It is shown that the application of a programmed sequence of magnetic pulses can invert the free evolution process, forcing an arbitrary wave packet to 'go back in time' to recover its past shape. The possibility of more general operations upon the Schrodinger wave packet is discussed.

  14. Software evolution with XVCL

    DEFF Research Database (Denmark)

    Zhang, Weishan; Jarzabek, Stan; Zhang, Hongyu

    2004-01-01

    This chapter introduces software evolution with XVCL (XML-based Variant Configuration Language), which is an XML-based metaprogramming technique. As the software evolves, a large number of variants may arise, especially whtn such kinds of evolutions are related to multiple platforms as shown in our...... case study. Handling variants and tracing the impact of variants across the development lifecycle is a challenge. This chapter shows how we can maintain different versions of software in a reuse-based way....

  15. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    2005-12-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. A prime application of characteristic evolution is to compute waveforms via Cauchy-characteristic matching, which is also reviewed.

  16. Evolution, museums and society.

    Science.gov (United States)

    MacFadden, Bruce J

    2008-11-01

    Visitors to natural history museums have an incomplete understanding of evolution. Although they are relatively knowledgeable about fossils and geological time, they have a poor understanding of natural selection. Museums in the 21st century can effectively increase public understanding of evolution through interactive displays, novel content (e.g. genomics), engaging videos and cyberexhibits that communicate to a broad spectrum of society, both within the exhibit halls as well as outside the museum.

  17. The theory of evolution

    Directory of Open Access Journals (Sweden)

    Oleg Bazaluk

    2015-06-01

    Full Text Available The book The Theory of Evolution: from the Space Vacuum to Neural Ensembles and Moving Forward, an edition of 100 copies, was published in Russian language, in December 2014 in Kiev. Its Russian version is here: http://en.bazaluk.com/journals.html. Introduction, Chapter 10 and Conclusion published in English for the first time. Since 2004 author have been researching in the field of theory of Evolution, Big History. The book was written on the base of analysis of more than 2000 primary sources of this research topic. The volume is 90,000 words (with Reference. The book is for a wide range of professionals, from students to professors and researchers working in the fields of: philosophical anthropology, philosophy, Big History, cosmology, biology, neuroscience and etc. In the book, the author defines the evolution as continuous and nonlinear complication of the structure of matter, the types of interaction and environments; analyzes existing in modern science and philosophy approaches to the research of the process of evolution, degree of development of the factors and causes of evolution. Unifying interdisciplinary researches of evolution in cosmology, biology, neuroscience and philosophy, the author presents his vision of the model of «Evolving Matter», which allows us to consider not only the laws of transition of space vacuum in neural ensembles but also to see our Universe as a complication, heterogeneous organization. Interdisciplinary amount of information on the theory of evolution is systematized and a new method of world perception is proposed in the book.

  18. Creationism, Evolution, and Science Education

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eugenie C. (National Center for Science Education)

    2005-06-22

    Many topics in the curriculum of American schools are controversial, but perhaps the one with the longest tenure is evolution. Three arguments are made against evolution: that it is allegedly weak science ('evolution is a theory in crisis'); that it is incompatible with religion; and that it is only 'fair' to 'balance' evolution with creationism. Regardless of the appropriateness of their application to science education, all three of the arguments are made to try to restrict the teaching of evolution. Variants of the fairness argument such as balancing evolution with 'scientific alternatives to evolution' or balancing evolution with 'arguments against evolution' have in fact become the current predominant antievolutionist strategy. Current events in the creationism/evolution controversy will be reviewed, and suggestions made for how to promote sound science education in the schools.

  19. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Jeffrey Winicour

    2012-01-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial-value problem. Progress in characteristic evolution is traced from the early stage of 1D feasibility studies to 2D-axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black-hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black-hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to extend such simulations to null infinity where the waveform from the binary inspiral and merger can be unambiguously computed. This has now been accomplished by Cauchy-characteristic extraction, where data for the characteristic evolution is supplied by Cauchy data on an extraction worldtube inside the artificial outer boundary. The ultimate application of characteristic evolution is to eliminate the role of this outer boundary by constructing a global solution via Cauchy-characteristic matching. Progress in this direction is discussed.

  20. The Evolution of Language

    Science.gov (United States)

    Nowak, Martin A.; Krakauer, David C.

    1999-07-01

    The emergence of language was a defining moment in the evolution of modern humans. It was an innovation that changed radically the character of human society. Here, we provide an approach to language evolution based on evolutionary game theory. We explore the ways in which protolanguages can evolve in a nonlinguistic society and how specific signals can become associated with specific objects. We assume that early in the evolution of language, errors in signaling and perception would be common. We model the probability of misunderstanding a signal and show that this limits the number of objects that can be described by a protolanguage. This "error limit" is not overcome by employing more sounds but by combining a small set of more easily distinguishable sounds into words. The process of "word formation" enables a language to encode an essentially unlimited number of objects. Next, we analyze how words can be combined into sentences and specify the conditions for the evolution of very simple grammatical rules. We argue that grammar originated as a simplified rule system that evolved by natural selection to reduce mistakes in communication. Our theory provides a systematic approach for thinking about the origin and evolution of human language.

  1. Workshop on Molecular Evolution

    Science.gov (United States)

    Cummings, Michael P.

    2004-01-01

    Molecular evolution has become the nexus of many areas of biological research. It both brings together and enriches such areas as biochemistry, molecular biology, microbiology, population genetics, systematics, developmental biology, genomics, bioinformatics, in vitro evolution, and molecular ecology. The Workshop provides an important contribution to these fields in that it promotes interdisciplinary research and interaction, and thus provides a glue that sticks together disparate fields. Due to the wide range of fields addressed by the study of molecular evolution, it is difficult to offer a comprehensive course in a university setting. It is rare for a single institution to maintain expertise in all necessary areas. In contrast, the Workshop is uniquely able to provide necessary breadth and depth by utilizing a large number of faculty with appropriate expertise. Furthermore, the flexible nature of the Workshop allows for rapid adaptation to changes in the dynamic field of molecular evolution. For example, the 2003 Workshop included recently emergent research areas of molecular evolution of development and genomics.

  2. Evolution of Things

    CERN Document Server

    Eiben, A E; Schut, M; Kernbach, S

    2011-01-01

    Evolution is one of the major omnipresent powers in the universe that has been studied for about two centuries. Recent scientific and technical developments make it possible to make the transition from passively understanding to actively mastering evolution. As of today, the only area where human experimenters can design and manipulate evolutionary processes in full is that of Evolutionary Computing, where evolutionary processes are carried out in a digital space, inside computers, in simulation. We argue that in the near future it will be possible to move evolutionary computing outside such imaginary spaces and make it physically embodied. In other words, we envision the "Evolution of Things", rather than just the evolution of code, leading to a new field of Embodied Artificial Evolution (EAE). The main objective of the present paper is to offer an umbrella term and vision in order to aid the development of this high potential research area. To this end, we introduce the notion of EAE, discuss a few examples...

  3. AGN evolution from a galaxy evolution viewpoint

    CERN Document Server

    Caplar, Neven; Trakhtenbrot, Benny

    2014-01-01

    We explore the connections between the evolving galaxy and AGN populations. We present a simple phenomenological model that links the evolving galaxy mass function and the evolving quasar luminosity function, motivated by similarities between the two, which makes specific and testable predictions for the distribution of host galaxy masses for AGN of different luminosities. We show that the phi$^{*}$ normalisations of the galaxy mass function and the AGN luminosity function closely track each other over a wide range of redshifts, implying a constant "duty cycle" of AGN activity. The strong redshift evolution in the AGN break luminosity $L^*$ is produced by either an evolution in the distribution of Eddington rations, or in the $m_{bh}/m_{*}$ mass ratio, or both. An evolving $m_{bh}/m_{*}$ ratio, such that it is ten times higher at $z \\sim 2$ (i.e. roughly following $(1+z)^{2}$), reproduces the observed distribution of SDSS quasars in the ($m_{bh},L$) plane and accounts for the apparent "sub-Eddington boundary"...

  4. Software architecture evolution

    DEFF Research Database (Denmark)

    Barais, Olivier; Le Meur, Anne-Francoise; Duchien, Laurence

    2008-01-01

    Software architectures must frequently evolve to cope with changing requirements, and this evolution often implies integrating new concerns. Unfortunately, when the new concerns are crosscutting, existing architecture description languages provide little or no support for this kind of evolution....... The software architect must modify multiple elements of the architecture manually, which risks introducing inconsistencies. This chapter provides an overview, comparison and detailed treatment of the various state-of-the-art approaches to describing and evolving software architectures. Furthermore, we discuss...... one particular framework named Tran SAT, which addresses the above problems of software architecture evolution. Tran SAT provides a new element in the software architecture descriptions language, called an architectural aspect, for describing new concerns and their integration into an existing...

  5. Ethics, evolution and culture.

    Science.gov (United States)

    Mesoudi, Alex; Danielson, Peter

    2008-08-01

    Recent work in the fields of evolutionary ethics and moral psychology appears to be converging on a single empirically- and evolutionary-based science of morality or ethics. To date, however, these fields have failed to provide an adequate conceptualisation of how culture affects the content and distribution of moral norms. This is particularly important for a large class of moral norms relating to rapidly changing technological or social environments, such as norms regarding the acceptability of genetically modified organisms. Here we suggest that a science of morality/ethics can benefit from adopting a cultural evolution or gene-culture coevolution approach, which treats culture as a second, separate evolutionary system that acts in parallel to biological/genetic evolution. This cultural evolution approach brings with it a set of established theoretical concepts (e.g. different cultural transmission mechanisms) and empirical methods (e.g. evolutionary game theory) that can significantly improve our understanding of human morality.

  6. Lossless Conditional Schema Evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Bøhlen, Michael Hanspeter

    2003-01-01

    The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples and the reco......The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples...... and the recorded schema of tuples is at the core of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that conditionally evolving schemas, in contrast to current commercial database systems, are lossless when the schema evolves...

  7. Evolution of Scale Worms

    DEFF Research Database (Denmark)

    Gonzalez, Brett Christopher

    of adaptability and convergent evolution between relatively closely related scale worms. While some morphological and behavioral modifications in cave polynoids reflected troglomorphism, other modifications like eye loss were found to stem from a common ancestor inhabiting the deep sea, further corroborating...... the deep sea ancestry of scale worm cave fauna. In conclusion, while morphological characterization across Aphroditiformia appears deceptively easy due to the presence of elytra, convergent evolution during multiple early radiations across wide ranging habitats have confounded our ability to reconstruct......) caves, and the interstitium, recovering six monophyletic clades within Aphroditiformia: Acoetidae, Aphroditidae, Eulepethidae, Iphionidae, Polynoidae, and Sigalionidae (inclusive of the former ‘Pisionidae’ and ‘Pholoidae’), respectively. Tracing of morphological character evolution showed a high degree...

  8. Lossless Conditional Schema Evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Bøhlen, Michael Hanspeter

    2003-01-01

    The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples and the reco......The paper considers conditional schema evolution, where schema changes change the schema of the tuples that satisfy the change condition. When the schema of a relation change some tuples may no longer fit the current schema. Handling the mismatch between the intended schema of tuples...... and the recorded schema of tuples is at the core of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that conditionally evolving schemas, in contrast to current commercial database systems, are lossless when the schema evolves...

  9. Boussinesq evolution equations

    DEFF Research Database (Denmark)

    Bredmose, Henrik; Schaffer, H.; Madsen, Per A.

    2004-01-01

    This paper deals with the possibility of using methods and ideas from time domain Boussinesq formulations in the corresponding frequency domain formulations. We term such frequency domain models "evolution equations". First, we demonstrate that the numerical efficiency of the deterministic...... Boussinesq evolution equations of Madsen and Sorensen [Madsen, P.A., Sorensen, O.R., 1993. Bound waves and triad interactions in shallow water. Ocean Eng. 20 359-388] can be improved by using Fast Fourier Transforms to evaluate the nonlinear terms. For a practical example of irregular waves propagating over...... a submerged bar, it is demonstrated that evolution equations utilising FFT can be solved around 100 times faster than the corresponding time domain model. Use of FFT provides an efficient bridge between the frequency domain and the time domain. We utilise this by adapting the surface roller model for wave...

  10. Evolution and Christian Faith

    Science.gov (United States)

    Roughgarden, J. E.

    2006-12-01

    My recent book, Evolution and Christian Faith explores how evolutionary biology can be portrayed from the religious perspective of Christianity. The principal metaphors for evolutionary biology---differential success at breeding and random mutation, probably originate with the dawn of agriculture and clearly occur in the Bible. The central narrative of evolutionary biology can be presented using Biblical passages, providing an account of evolution that is inherently friendly to a Christian perspective. Still, evolutionary biology is far from complete, and problematic areas pertain to species in which the concept of an individual is poorly defined, and to species in which the expression of gender and sexuality depart from Darwin's sexual-selection templates. The present- day controversy in the US about teaching evolution in the schools provides an opportunity to engage the public about science education.

  11. Cultural evolution and personalization

    CERN Document Server

    Xi, Ning; Zhang, Yi-Cheng

    2012-01-01

    In social sciences, there is currently no consensus on the mechanism for cultural evolution. The evolution of first names of newborn babies offers a remarkable example for the researches in the field. Here we perform statistical analyses on over 100 years of data in the United States. We focus in particular on how the frequency-rank distribution and inequality of baby names change over time. We propose a stochastic model where name choice is determined by personalized preference and social influence. Remarkably, variations on the strength of personalized preference can account satisfactorily for the observed empirical features. Therefore, we claim that personalization drives cultural evolution, at least in the example of baby names.

  12. Parton distributions incorporating QED contributions

    CERN Document Server

    Martin, A D; Stirling, W J; Thorne, R S

    2004-01-01

    We perform a global parton analysis of deep inelastic and related hard-scattering data, including ${\\cal O}(\\alpha_{\\rm QED})$ corrections to the parton evolution. Although the quality of the fit is essentially unchanged, there are two important physical consequences. First, the different DGLAP evolution of u and d type quarks introduces isospin violation, i.e. $u^p \

  13. Computational evolution: taking liberties.

    Science.gov (United States)

    Correia, Luís

    2010-09-01

    Evolution has, for a long time, inspired computer scientists to produce computer models mimicking its behavior. Evolutionary algorithm (EA) is one of the areas where this approach has flourished. EAs have been used to model and study evolution, but they have been especially developed for their aptitude as optimization tools for engineering. Developed models are quite simple in comparison with their natural sources of inspiration. However, since EAs run on computers, we have the freedom, especially in optimization models, to test approaches both realistic and outright speculative, from the biological point of view. In this article, we discuss different common evolutionary algorithm models, and then present some alternatives of interest. These include biologically inspired models, such as co-evolution and, in particular, symbiogenetics and outright artificial operators and representations. In each case, the advantages of the modifications to the standard model are identified. The other area of computational evolution, which has allowed us to study basic principles of evolution and ecology dynamics, is the development of artificial life platforms for open-ended evolution of artificial organisms. With these platforms, biologists can test theories by directly manipulating individuals and operators, observing the resulting effects in a realistic way. An overview of the most prominent of such environments is also presented. If instead of artificial platforms we use the real world for evolving artificial life, then we are dealing with evolutionary robotics (ERs). A brief description of this area is presented, analyzing its relations to biology. Finally, we present the conclusions and identify future research avenues in the frontier of computation and biology. Hopefully, this will help to draw the attention of more biologists and computer scientists to the benefits of such interdisciplinary research.

  14. Antimycobacterial, antimicrobial activity, experimental (FT-IR, FT-Raman, NMR, UV-Vis, DSC) and DFT (transition state, chemical reactivity, NBO, NLO) studies on pyrrole-isonicotinyl hydrazine.

    Science.gov (United States)

    Rawat, Poonam; Singh, R N; Ranjan, Alok; Ahmad, Sartaj; Saxena, Rajat

    2017-05-15

    As part of a study of pyrrole hydrazone, we have investigated quantum chemical calculations, molecular geometry, relative energy, vibrational properties and antimycobacterial/antimicrobial activity of pyrrole-2-carboxaldehyde isonicotinyl hydrazone (PCINH), by applying the density functional theory (DFT) and Hartree Fock (HF). Good reproduction of experimental values is obtained and with small percentage error in majority of the cases in comparison to theoretical result (DFT). The experimental FT-IR and Raman wavenumbers were compared with the respective theoretical values obtained from DFT calculations and found to agree well. In crystal structure studies the hydrated PCINH (syn-syn conformer) shows different conformation than from anhydrous form (syn-anti conformer). The rotational barrier between syn-syn and syn-anti conformers of PCINH is 12.7kcal/mol in the gas phase. In this work, use of FT-IR, FT-Raman, (1)H NMR, (13)C NMR and UV-Vis spectroscopies has been made for full characterization of PCINH. A detailed interpretation of the vibrational spectrum was carried out with the aid of normal coordinate analysis using single scaling factor. Our results support the hydrogen bonding pattern proposed by reported crystalline structure. The calculated nature of electronic transitions within molecule found to be π→π*. The electronic descriptors study indicates that PCINH can be used as robust synthon for synthesis of new heterocyclic compounds. The first static hyperpolarizability (β0) of PCINH is calculated as 33.89×10(-30)esu, (gas phase); 68.79×10(-30) (CHCl3), esu; 76.76×10(-30)esu (CH2Cl2), 85.16×10(-30)esu (DMSO). The solvent induced effects on the first static hyperpolarizability were studied and found to increase as dielectric constants of the solvents increases. Investigated molecule shows better NLO value than Para nitroaniline (PNA). The compound PCINH shows good antifungal and antibacterial activity against Aspergillus niger and gram

  15. Bulk growth of undoped and Nd3+ doped zinc thiourea chloride (ZTC) monocrystal: Exploring the remarkably enhanced structural, optical, electrical and mechanical performance of Nd3+ doped ZTC crystal for NLO device applications

    Science.gov (United States)

    Anis, Mohd; Muley, Gajanan. G.

    2017-05-01

    In current scenario good quality crystals are demanded for NLO device application hence present communication is aimed to grow bulk crystal and investigate the doping effect of rare earth element Nd3+ on structural, linear-nonlinear optical, luminescence, mechanical and dielectric properties of zinc thiourea chloride (ZTC) crystal. The ZTC crystal of dimension 21×10×8 mm3 and the Nd3+ doped ZTC crystal of dimension 27×17×5 mm3 have been grown from aqueous solution by slow evaporation technique. The elemental analysis of Nd3+ doped ZTC single crystal has been performed by means of energy dispersive spectroscopic technique. The powder X-ray diffraction technique has been employed to confirm the crystalline phase and identify the effect of Nd3+ doping on structural dimensions of ZTC crystal. The grown crystals have been characterized by UV-Vis-NIR study in the range of 190-1100 nm to ascertain the enhancement in optical transparency of ZTC crystal facilitated by dopant Nd3+. The recorded transmittance data has been utilized to investigate the vital optical constants of grown crystals. The second order nonlinear optical behavior of grown crystals has been evaluated by means of Kurtz-Perry test and the second harmonic generation efficiency of Nd3+ doped ZTC crystal is found to be 1.24 times higher than ZTC crystal. The luminescence analysis has been performed to examine the electronic purity and the color centered photoluminescence emission nature of pure and Nd3+ doped ZTC crystals. The influence of Nd3+ ion on mechanical behavior of ZTC crystal has been investigated by means of microhardness studies. The nature of dielectric constant and dielectric loss of pure and Nd3+ doped ZTC crystal has been examined in the range of 40-100 °C under dielectric study. The Z-scan technique has been employed using the He-Ne laser to investigate the third order nonlinear optical (TONLO) nature of Nd3+ doped ZTC single crystal. The magnitude of TONLO susceptibility, absorption

  16. Managing Software Process Evolution

    DEFF Research Database (Denmark)

    This book focuses on the design, development, management, governance and application of evolving software processes that are aligned with changing business objectives, such as expansion to new domains or shifting to global production. In the context of an evolving business world, it examines...... essential insights and tips to help readers manage process evolutions. And last but not least, it provides a wealth of examples and cases on how to deal with software evolution in practice. Reflecting these topics, the book is divided into three parts. Part 1 focuses on software business transformation...... the organization and management of (software development) projects and process improvements projects....

  17. TMDs: Evolution, modeling, precision

    Directory of Open Access Journals (Sweden)

    D’Alesio Umberto

    2015-01-01

    Full Text Available The factorization theorem for qT spectra in Drell-Yan processes, boson production and semi-inclusive deep inelastic scattering allows for the determination of the non-perturbative parts of transverse momentum dependent parton distribution functions. Here we discuss the fit of Drell-Yan and Z-production data using the transverse momentum dependent formalism and the resummation of the evolution kernel. We find a good theoretical stability of the results and a final χ2/points ≲ 1. We show how the fixing of the non-perturbative pieces of the evolution can be used to make predictions at present and future colliders.

  18. [Biological evolution and specialization].

    Science.gov (United States)

    Luo, Weizhen; Wang, Deli

    2003-12-01

    There were some disputes about the concept and mechanism of biological evolution. This paper tried to give more explanations on the key concepts. The biological adaptability was distinguished into two different concepts: biological evolution and specialization. The former was defined as the process of biologically gradual evolvement, and the latter was considered as the process of species formation at horizontal development. Moreover, a new conceptual framework was applied to the popular biological theories known by people, and the previous research results or discoveries were explained over again.

  19. Evolution and social epidemiology.

    Science.gov (United States)

    Nishi, Akihiro

    2015-11-01

    Evolutionary biology, which aims to explain the dynamic process of shaping the diversity of life, has not yet significantly affected thinking in social epidemiology. Current challenges in social epidemiology include understanding how social exposures can affect our biology, explaining the dynamics of society and health, and designing better interventions that are mindful of the impact of exposures during critical periods. I review how evolutionary concepts and tools, such as fitness gradient in cultural evolution, evolutionary game theory, and contemporary evolution in cancer, can provide helpful insights regarding social epidemiology.

  20. TMDs: Evolution, modeling, precision

    CERN Document Server

    D'Alesio, Umberto; Melis, Stefano; Scimemi, Ignazio

    2014-01-01

    The factorization theorem for $q_T$ spectra in Drell-Yan processes, boson production and semi-inclusive deep inelastic scattering allows for the determination of the non-perturbative parts of transverse momentum dependent parton distribution functions. Here we discuss the fit of Drell-Yan and $Z$-production data using the transverse momentum dependent formalism and the resummation of the evolution kernel. We find a good theoretical stability of the results and a final $\\chi^2/{\\rm points}\\lesssim 1$. We show how the fixing of the non-perturbative pieces of the evolution can be used to make predictions at present and future colliders.

  1. Macrothermodynamics of Biological Evolution:

    Science.gov (United States)

    Gladyshev, Georgi P.

    The author sets forth general considerations pertaining to the thermodynamic theory of biological evolution and the aging of living organisms. It becomes much easier to comprehend the phenomenon of life scrutinizing the formation of structural hierarchies of biological matter applying different temporal scales. These scales are 'identified' by nature itself, and this is reflected in the law of temporal hierarchies. The author discusses some misunderstandings in thermodynamics and evolutionary biology. A simple physicochemical model of biological evolution and the development of living beings is proposed. The considered theory makes it possible to use physicochemical evaluations to develop effective anti-aging diets.

  2. Controlled quantum evolutions

    CERN Document Server

    Petroni, N C; De Siena, S; Illuminati, F; Petroni, Nicola Cufaro; Martino, Salvatore De; Siena, Silvio De; Illuminati, Fabrizio

    1999-01-01

    We perform a detailed analysis of the non stationary solutions of the evolution (Fokker-Planck) equations associated to either stationary or non stationary quantum states by the stochastic mechanics. For the excited stationary states of quantum systems with singular velocity fields we explicitely discuss the exact solutions for the HO case. Moreover the possibility of modifying the original potentials in order to implement arbitrary evolutions ruled by these equations is discussed with respect to both possible models for quantum measurements and applications to the control of particle beams in accelerators.

  3. Manufacturing network evolution

    DEFF Research Database (Denmark)

    Yang, Cheng; Farooq, Sami; Johansen, John

    2011-01-01

    Purpose – This paper examines the effect of changes at the manufacturing plant level on other plants in the manufacturing network and also investigates the role of manufacturing plants on the evolution of a manufacturing network. Design/methodology/approach –The research questions are developed......, the complex phenomenon of a manufacturing network evolution is observed by combining the analysis of a manufacturing plant and network level. The historical trajectories of manufacturing networks that are presented in the case studies are examined in order to understand and determine the future shape...

  4. Emergence and Evolution

    DEFF Research Database (Denmark)

    Bullwinkle, Tammy J; Ibba, Michael

    2013-01-01

    ancestor and as such they provide insights into the evolution and development of the extant genetic code. Although the aaRSs have long been viewed as a highly conserved group of enzymes, findings within the last couple of decades have started to demonstrate how diverse and versatile these enzymes really...... are. Beyond their central role in translation, aaRSs and their numerous homologs have evolved a wide array of alternative functions both inside and outside translation. Current understanding of the emergence of the aaRSs, and their subsequent evolution into a functionally diverse enzyme family...

  5. Evolution Perception with Metaphors

    Science.gov (United States)

    Yilmaz, Fatih

    2016-01-01

    The main objective of this research is to find out how the teacher candidates who graduated from the Faculty of Theology and study in pedagogical formation program perceive the theory of evolution. Having a descriptive characteristic, this research is conducted with 63 Faculty of Theology graduate teacher candidates of which 36 is women and 27 is…

  6. The Evolution of Darwinism.

    Science.gov (United States)

    Stebbins, G. Ledyard; Ayala, Francisco J.

    1985-01-01

    Recent developments in molecular biology and new interpretations of the fossil record are gradually altering and adding to Charles Darwin's theory, which has been the standard view of the process of evolution for 40 years. Several of these developments and interpretations are identified and discussed. (JN)

  7. Human Development, Human Evolution.

    Science.gov (United States)

    Smillie, David

    One of the truly remarkable events in human evolution is the unprecedented increase in the size of the brain of "Homo" over a brief span of 2 million years. It would appear that some significant selective pressure or opportunity presented itself to this branch of the hominid line and caused a rapid increase in the brain, introducing a…

  8. Electrochemical Hydrogen Evolution

    DEFF Research Database (Denmark)

    Laursen, A.B.; Varela Gasque, Ana Sofia; Dionigi, F.

    2012-01-01

    The electrochemical hydrogen evolution reaction (HER) is growing in significance as society begins to rely more on renewable energy sources such as wind and solar power. Thus, research on designing new, inexpensive, and abundant HER catalysts is important. Here, we describe how a simple experimen...

  9. Titan Polar Landscape Evolution

    Science.gov (United States)

    Moore, Jeffrey M.

    2016-01-01

    With the ongoing Cassini-era observations and studies of Titan it is clear that the intensity and distribution of surface processes (particularly fluvial erosion by methane and Aeolian transport) has changed through time. Currently however, alternate hypotheses substantially differ among specific scenarios with respect to the effects of atmospheric evolution, seasonal changes, and endogenic processes. We have studied the evolution of Titan's polar region through a combination of analysis of imaging, elevation data, and geomorphic mapping, spatially explicit simulations of landform evolution, and quantitative comparison of the simulated landscapes with corresponding Titan morphology. We have quantitatively evaluated alternate scenarios for the landform evolution of Titan's polar terrain. The investigations have been guided by recent geomorphic mapping and topographic characterization of the polar regions that are used to frame hypotheses of process interactions, which have been evaluated using simulation modeling. Topographic information about Titan's polar region is be based on SAR-Topography and altimetry archived on PDS, SAR-based stereo radar-grammetry, radar-sounding lake depth measurements, and superposition relationships between geomorphologic map units, which we will use to create a generalized topographic map.

  10. Software Architecture Evolution

    Science.gov (United States)

    Barnes, Jeffrey M.

    2013-01-01

    Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

  11. Evolution 2.0

    DEFF Research Database (Denmark)

    Andersen, Casper; Bek-Thomsen, Jakob; Clasen, Mathias

    2013-01-01

    Studies in the history of science and education have documented that the reception and understanding of evolutionary theory is highly contingent on local factors such as school systems, cultural traditions, religious beliefs, and language. This has important implications for teaching evolution...

  12. The Evolution of Behavior.

    Science.gov (United States)

    Smith, John Maynard

    1978-01-01

    The topic of altruistic behavior is an important one in studying the evolution of behavior. It is questioned whether natural selection can actually favor patterns of behavior that apparently do not favor the survival of the individual. Game theory models are presented to help explore the problem. (MA)

  13. Evolution of Business Models

    DEFF Research Database (Denmark)

    Antero, Michelle C.; Hedman, Jonas; Henningsson, Stefan

    2013-01-01

    The ERP industry has undergone dramatic changes over the past decades due to changing market demands, thereby creating new challenges and opportunities, which have to be managed by ERP vendors. This paper inquires into the necessary evolution of business models in a technology-intensive industry (e......, by adopting different value configurations to reflect the convergence of customers, suppliers and vendors....

  14. Evolution Through Architectural Reconciliation

    NARCIS (Netherlands)

    Avgeriou, Paris; Guelfi, Nicolas; Perrouin, Gilles

    2005-01-01

    One of the possible scenarios in a system evolution cycle, is to translate an emergent set of new requirements into software architecture design and subsequently to update the system implementation. In this paper, we argue that this form of forward engineering, even though addresses the new system r

  15. Evolution of rhizobium symbiosis

    NARCIS (Netherlands)

    Camp, Op den R.H.M.

    2012-01-01

    The evolution of rhizobium symbiosis is studied from several points of view in this thesis. The ultimate goal of the combined approaches is to unravel the genetic constrains of the symbiotic interaction. To this end the legume rhizobium symbiosis is studied in model plant species from the Papilionoi

  16. Explaining Poverty Evolution

    DEFF Research Database (Denmark)

    Arndt, Channing; Hussain, Mohammad Azhar; Jones, Edward Samuel

    consumption in Mozambique to examine the evolution of consumption poverty with focus on the period 2002/03 to 2008/09. The paper contributes in four areas. First, the period in question was characterized by major movements in international commodity prices. Mozambique provides an illuminating case study...

  17. Lossless conditional schema evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Böhlen, Michael

    2004-01-01

    of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that evolving schemas with conditional schema changes, in contrast to database systems relying on data migration, are lossless when the schema evolves. The lossless property...

  18. Evolution of subsidiary competences

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Pedersen, Torben; Dhanaraj, Charles

    of competitive advantage of nations, we hypothesize the contingencies under which heterogeneity in host environments influences subsidiary competence configuration. We test our model with data from more than 2,000 subsidiaries in seven Western European countries. Our results provide new insights on the evolution...

  19. Open-Ended Evolution

    DEFF Research Database (Denmark)

    Taylor, Tim; A. Bedau, Mark; Channon, Alastair

    2016-01-01

    This report describes the First Workshop on Open-Ended Evolution: Recent Progress and Future Milestones (OEE1), held during the ECAL 2015 conference at the University of York, U.K., in July 2015. We briefly summarise the content of the talks and discussions and the workshop, and provide links...

  20. Collection Evaluation and Evolution

    Science.gov (United States)

    Habermann, Ted; Kozimor, John

    2017-01-01

    We will review metadata evaluation tools and share results from our most recent CMR analysis. We will demonstrate results using Google spreadsheets and present new results in terms of number of records that include specific content. We will show evolution of UMM-compliance over time and also show results of comparing various CMR collections (NASA, non-NASA, and SciOps).

  1. Darwinism: Evolution or Revolution?

    Science.gov (United States)

    Holt, Niles R.

    1989-01-01

    Maintains that Darwin's theory of evolution was more than a science versus religion debate; rather it was a revolutionary concept that influenced numerous social and political ideologies and movements throughout western history. Traces the impact of Darwin's work historically, utilizing a holistic approach. (RW)

  2. Evolution and Flow.

    Science.gov (United States)

    Csikszentmihalyi, Mihaly

    1997-01-01

    Presents flow theory in the context of evolution. Defines the elements of "flow" and contends that flow results in an optimal state of inner harmony which improves one's chance for survival. Identifies consequences of flow for creativity, peak performance, talent development, productivity, self-esteem, and stress reduction. Examines the…

  3. Evolution of rhizobium symbiosis

    NARCIS (Netherlands)

    Camp, Op den R.H.M.

    2012-01-01

    The evolution of rhizobium symbiosis is studied from several points of view in this thesis. The ultimate goal of the combined approaches is to unravel the genetic constrains of the symbiotic interaction. To this end the legume rhizobium symbiosis is studied in model plant species from the

  4. Early cellular evolution.

    Science.gov (United States)

    Margulis, L.

    1972-01-01

    Study of the evolutionary developments that occurred subsequent to the origin of ancestral cells. Microbial physiology and ecology are potential sharp tools for shaping concepts of microbial evolution. Some popular unjustified assumptions are discussed. It is considered that certain principles derived mainly from the advances of molecular biology can be used to order the natural groups (genera) of extant prokaryotes and their patterns phylogenetically.

  5. Evolution of subsidiary competences

    DEFF Research Database (Denmark)

    Geisler Asmussen, Christian; Pedersen, Torben; Dhanaraj, Charles

    of competitive advantage of nations, we hypothesize the contingencies under which heterogeneity in host environments influences subsidiary competence configuration. We test our model with data from more than 2,000 subsidiaries in seven Western European countries. Our results provide new insights on the evolution...

  6. Open-Ended Evolution

    DEFF Research Database (Denmark)

    Taylor, Tim; A. Bedau, Mark; Channon, Alastair

    2016-01-01

    This report describes the First Workshop on Open-Ended Evolution: Recent Progress and Future Milestones (OEE1), held during the ECAL 2015 conference at the University of York, U.K., in July 2015. We briefly summarise the content of the talks and discussions and the workshop, and provide links...

  7. Lossless conditional schema evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Böhlen, Michael

    2004-01-01

    of a DBMS that supports schema evolution. We propose to keep track of schema mismatches at the level of individual tuples, and prove that evolving schemas with conditional schema changes, in contrast to database systems relying on data migration, are lossless when the schema evolves. The lossless property...

  8. Evolution of housing

    NARCIS (Netherlands)

    Slob, C.; Mohammadi, S.; Geraedts, R.P.

    2012-01-01

    ‘Perfection means something is complete and stands still and what stands still doesn’t change or evolve and is automatically dead. Everything in the universe changes, evolution implies that the creation is not complete hence the possibility of evolving’ (Osho, 1985). Our society and economy are

  9. Methylome evolution in plants

    NARCIS (Netherlands)

    Vidalis, Amaryllis; Živković, Daniel; Wardenaar, René; Roquis, David; Tellier, Aurélien; Johannes, Frank

    2016-01-01

    Despite major progress in dissecting the molecular pathways that control DNA methylation patterns in plants, little is known about the mechanisms that shape plant methylomes over evolutionary time. Drawing on recent intra- and interspecific epigenomic studies, we show that methylome evolution over

  10. EVOLUTION OF INSURANCE DEFINITION

    Directory of Open Access Journals (Sweden)

    V. A. Gorb

    2011-03-01

    Full Text Available In the article the evolution of the concept of insurance from the earliest forms to contemporary ones is shown. The development of insurance in Ukraine is demonstrated. A review of transformation of the insurance concept is presented in tabular form.

  11. Software Architecture Evolution

    Science.gov (United States)

    Barnes, Jeffrey M.

    2013-01-01

    Many software systems eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the causes, architecture evolution is commonplace in real-world software projects. Today's software architects, however,…

  12. Glossogeny and phylogeny: cultural evolution meets genetic evolution.

    Science.gov (United States)

    Fitch, W Tecumseh

    2008-08-01

    Evolutionary theorists since Darwin have been interested in the parallels and interactions between biological and cultural evolution. Recent applications of empirical techniques originally developed to analyze molecular genetic data to linguistic data offer new insights into the historical evolution of language, revealing fascinating parallels between language change and biological evolution. This work offers considerable potential toward unified theories of genetic and cultural change.

  13. Viral Evolution Core | FNLCR Staging

    Science.gov (United States)

    Brandon F. Keele, Ph.D. PI/Senior Principal Investigator, Retroviral Evolution Section Head, Viral Evolution Core Leidos Biomedical Research, Inc. Frederick National Laboratory for Cancer Research Frederick, MD 21702-1201 Tel: 301-846-173

  14. Hardware Evolution of Control Electronics

    Science.gov (United States)

    Gwaltney, David; Steincamp, Jim; Corder, Eric; King, Ken; Ferguson, M. I.; Dutton, Ken

    2003-01-01

    The evolution of closed-loop motor speed controllers implemented on the JPL FPTA2 is presented. The response of evolved controller to sinusoidal commands, controller reconfiguration for fault tolerance,and hardware evolution are described.

  15. Evolution as Fact and Theory.

    Science.gov (United States)

    Gould, Stephen Jay

    1981-01-01

    This essay by a Harvard evolutionist presents viewpoints concerning the creationists' arguments against evolutionary biology. Semantics regarding "facts" and "theory" of evolution are examined, examples are cited of creationist argument, and arguments for evolution are presented. (CS)

  16. Elementary evolutions in Banach algebra

    OpenAIRE

    Lindsay, J. Martin; Das, Bata Krishna

    2013-01-01

    An elementary class of evolutions in unital Banach algebras is obtained by integrating product functions over Guichardet's symmetric measure space on the half-line. These evolutions, along with a useful subclass, are characterised and a Lie-Trotter product formula is proved. The class is rich enough to form the basis for a recent approach to quantum stochastic evolutions.

  17. Evolution of Brain and Language

    Science.gov (United States)

    Schoenemann, P. Thomas

    2009-01-01

    The evolution of language and the evolution of the brain are tightly interlinked. Language evolution represents a special kind of adaptation, in part because language is a complex behavior (as opposed to a physical feature) but also because changes are adaptive only to the extent that they increase either one's understanding of others, or one's…

  18. On Genetic and Evolution Algebras

    Science.gov (United States)

    Qaralleh, Izzat

    2017-03-01

    The genetic and evolution algebras generally are non-associative algebra. The concept of evolution and genetic algebras were introduced to answer the question what non-Mendelian genetics offers to mathematics. This paper we review some results of evolution and genetic algebras.

  19. Fla. Panel's Evolution Vote Hailed

    Science.gov (United States)

    Cavanagh, Sean

    2008-01-01

    This article reports on how the compromise hammered out in Florida recently over the treatment of evolution in the state's science classrooms is winning praise from scientists and educators. The new science standards will refer to evolution as the "scientific theory of evolution." These changes will replace more-general language in the…

  20. Evolution of Brain and Language

    Science.gov (United States)

    Schoenemann, P. Thomas

    2009-01-01

    The evolution of language and the evolution of the brain are tightly interlinked. Language evolution represents a special kind of adaptation, in part because language is a complex behavior (as opposed to a physical feature) but also because changes are adaptive only to the extent that they increase either one's understanding of others, or one's…

  1. Fla. Panel's Evolution Vote Hailed

    Science.gov (United States)

    Cavanagh, Sean

    2008-01-01

    This article reports on how the compromise hammered out in Florida recently over the treatment of evolution in the state's science classrooms is winning praise from scientists and educators. The new science standards will refer to evolution as the "scientific theory of evolution." These changes will replace more-general language in the previous…

  2. Expanding the Understanding of Evolution

    Science.gov (United States)

    Musante, Susan

    2011-01-01

    Originally designed for K-12 teachers, the Understanding Evolution (UE) Web site ("www.understandingevolution.org") is a one-stop shop for all of a teacher's evolution education needs, with lesson plans, teaching tips, lists of common evolution misconceptions, and much more. However, during the past five years, the UE project team learned that…

  3. Spin structure function g_1 at small x and arbitrary $Q^2: Total resummaion of leading logarithms vs Standard Approach

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2007-01-01

    The Standard Approach (SA) for description of the structure function g_1 combines the DGLAP evolution equations and Standard Fits for the initial parton densities. The DGLAP equations describe the region of large Q^2 and large x, so there are not theoretical grounds to exploit them at small x. In practice, extrapolation of DGLAP into the region of large Q^2 and small x is done with complementing DGLAP with special, singular (~x^{-a}) phenomenological fits for the initial parton densities. The factors x^{-a} are wrongly believed to be of the non-perturbative origin. Actually, they mimic the resummation of logs of x and should be expelled from the fits when the resummation is accounted for. Contrary to SA, the resummaton of logarithms of x is a straightforward and natural way to describe g_1 in the small-x region. This approach can be used at both large and small Q^2 where DGLAP cannot be used by definition. Confronting this approach and SA demonstrates that the singular initial parton densities and the power Q...

  4. Characteristic Evolution and Matching

    Directory of Open Access Journals (Sweden)

    Winicour Jeffrey

    2009-04-01

    Full Text Available I review the development of numerical evolution codes for general relativity based upon the characteristic initial value problem. Progress is traced from the early stage of 1D feasibility studies to 2D axisymmetric codes that accurately simulate the oscillations and gravitational collapse of relativistic stars and to current 3D codes that provide pieces of a binary black hole spacetime. Cauchy codes have now been successful at simulating all aspects of the binary black hole problem inside an artificially constructed outer boundary. A prime application of characteristic evolution is to eliminate the role of this artificial outer boundary via Cauchy-characteristic matching, by which the radiated waveform can be computed at null infinity. Progress in this direction is discussed.

  5. Kamikazes and cultural evolution.

    Science.gov (United States)

    Allen-Hermanson, Sean

    2017-02-01

    Is cultural evolution needed to explain altruistic selfsacrifice? Some contend that cultural traits (e.g. beliefs, behaviors, and for some "memes") replicate according to selection processes that have "floated free" from biology. One test case is the example of suicide kamikaze attacks in wartime Japan. Standard biological mechanisms-such as reciprocal altruism and kin selection-might not seem to apply here: The suicide pilots did not act on the expectation that others would reciprocate, and they were supposedly sacrificing themselves for country and emperor, not close relatives. Yet an examination of both the historical record and the demands of evolutionary theory suggest the kamikaze phenomenon does not cry out for explanation in terms of a special non-biological selection process. This weakens the case for cultural evolution, and has interesting implications for our understanding of altruistic self-sacrifice. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Evolution of clustered storage

    CERN Document Server

    CERN. Geneva; Van de Vyvre, Pierre

    2007-01-01

    The session actually featured two presentations: * Evolution of clustered storage by Lance Hukill, Quantum Corporation * ALICE DAQ - Usage of a Cluster-File System: Quantum StorNext by Pierre Vande Vyvre, CERN-PH the second one prepared at short notice by Pierre (thanks!) to present how the Quantum technologies are being used in the ALICE experiment. The abstract to Mr Hukill's follows. Clustered Storage is a technology that is driven by business and mission applications. The evolution of Clustered Storage solutions starts first at the alignment between End-users needs and Industry trends: * Push-and-Pull between managing for today versus planning for tomorrow * Breaking down the real business problems to the core applications * Commoditization of clients, servers, and target devices * Interchangeability, Interoperability, Remote Access, Centralized control * Oh, and yes, there is a budget and the "real world" to deal with This presentation will talk through these needs and trends, and then ask the question, ...

  7. Epigenetics and brain evolution.

    Science.gov (United States)

    Keverne, Eric B

    2011-04-01

    Fundamental aspects of mammalian brain evolution occurred in the context of viviparity and placentation brought about by the epigenetic regulation of imprinted genes. Since the fetal placenta hormonally primes the maternal brain, two genomes in one individual are transgenerationally co-adapted to ensure maternal care and nurturing. Advanced aspects of neocortical brain evolution has shown very few genetic changes between monkeys and humans. Although these lineages diverged at approximately the same time as the rat and mouse (20 million years ago), synonymous sequence divergence between the rat and mouse is double that when comparing monkey with human sequences. Paradoxically, encephalization of rat and mouse are remarkably similar, while comparison of the human and monkey shows the human cortex to be three times the size of the monkey. This suggests an element of genetic stability between the brains of monkey and man with a greater emphasis on epigenetics providing adaptable variability.

  8. Emergence and Evolution

    DEFF Research Database (Denmark)

    Bullwinkle, Tammy J; Ibba, Michael

    2013-01-01

    ancestor and as such they provide insights into the evolution and development of the extant genetic code. Although the aaRSs have long been viewed as a highly conserved group of enzymes, findings within the last couple of decades have started to demonstrate how diverse and versatile these enzymes really......The aminoacyl-tRNA synthetases (aaRSs) are essential components of the protein synthesis machinery responsible for defining the genetic code by pairing the correct amino acids to their cognate tRNAs. The aaRSs are an ancient enzyme family believed to have origins that may predate the last common...... are. Beyond their central role in translation, aaRSs and their numerous homologs have evolved a wide array of alternative functions both inside and outside translation. Current understanding of the emergence of the aaRSs, and their subsequent evolution into a functionally diverse enzyme family...

  9. Evolution of mycorrhiza systems

    Science.gov (United States)

    Cairney, J. W. G.

    Most terrestrial plants live in mutualistic symbiosis with root-infecting mycorrhizal fungi. Fossil records and molecular clock dating suggest that all extant land plants have arisen from an ancestral arbuscular mycorrhizal condition. Arbuscular mycorrhizas evolved concurrently with the first colonisation of land by plants some 450-500 million years ago and persist in most extant plant taxa. Ectomycorrhizas (about 200million years ago) and ericoid mycorrhizas (about 100million years ago) evolved subsequently as the organic matter content of some ancient soils increased and sclerophyllous vegetation arose as a response to nutrient-poor soils respectively. Mycorrhizal associations appear to be the result of relatively diffuse coevolutionary processes. While early events in the evolution of mycorrhizal symbioses may have involved reciprocal genetic changes in ancestral plants and free-living fungi, available evidence points largely to ongoing parallel evolution of the partners in response to environmental change.

  10. Evolution 2.0

    DEFF Research Database (Denmark)

    Andersen, Casper; Bek-Thomsen, Jakob; Clasen, Mathias

    2013-01-01

    Studies in the history of science and education have documented that the reception and understanding of evolutionary theory is highly contingent on local factors such as school systems, cultural traditions, religious beliefs, and language. This has important implications for teaching evolution...... in primary and secondary schools. No universal strategy can be applied in overcoming the barriers of learning that exist and that are part of the practical and daily life in classrooms all over the world. In light of this, a huge challenge is to make high standard teaching materials fit to specific target...... audiences readily available. As more and more schools require teachers to use low cost or free web-based materials, in the research community we need to take seriously how to facilitate that demand in communication strategies on evolution. This article addresses this challenge by presenting the learning...

  11. Environment and Protostellar Evolution

    CERN Document Server

    Zhang, Yichen

    2014-01-01

    Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of resulting star and planetary systems. Here we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focussing on low-mass, Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster (ONC), to very high pressures that may be found in the densest Infrared Dark Clouds (IRDCs) or in the Galactic Center (GC). We present unified analytic and numerical models for collapse of prestellar cores, accretion disks, protostellar evolution and bipolar outflows, coupled to radiative transfer (RT) calculations and a simple astrochemical model to predict CO gas phase abundances. Prestellar cores in high pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting...

  12. Evolution to Autonomy

    Directory of Open Access Journals (Sweden)

    Horace Lockwood Fairlamb

    2007-08-01

    Full Text Available Since both modern moral theory and evolutionary theory arose in the shadow of Newtonian and Humean conceptions of nature, debates about evolutionary ethics have typically been vexed by deeper problems with the nature of evolution itself as well as meta-ethical questions about the link between facts and values. Humean skepticism and mechanistic selectionism have recently coincided in postmodern attacks on essentialism,on meta-narratives of progress, on models of human nature, and on moral collectivism. Against this most recent wave of skepticism, however, contemporary reconstructions of evolution in light of complex systems science suggest useful ways of reinterpreting both evolutionary causation, the biology of human nature, and their implications for ethics.

  13. QCD Evolution Workshop

    CERN Document Server

    2015-01-01

    These are the proceedings of the QCD Evolution 2015 Workshop which was held 26–30 May, 2015 at Jefferson Lab, Newport News, Virginia, USA. The workshop is a continuation of a series of workshops held during four consecutive years 2011, 2012, 2013 at Jefferson Lab, and in 2014 in Santa Fe, NM. With the rapid developments in our understanding of the evolution of parton distributions including low-x, TMDs, GPDs, higher-twist correlation functions, and the associated progress in perturbative QCD, lattice QCD and effective field theory techniques we look forward with great enthusiasm to the 2015 meeting. A special attention was also paid to participation of experimentalists as the topics discussed are of immediate importance for the JLab 12 experimental program and a future Electron Ion Collider.

  14. The evolution of helicopters

    Science.gov (United States)

    Chen, R.; Wen, C. Y.; Lorente, S.; Bejan, A.

    2016-07-01

    Here, we show that during their half-century history, helicopters have been evolving into geometrically similar architectures with surprisingly sharp correlations between dimensions, performance, and body size. For example, proportionalities emerge between body size, engine size, and the fuel load. Furthermore, the engine efficiency increases with the engine size, and the propeller radius is roughly the same as the length scale of the whole body. These trends are in accord with the constructal law, which accounts for the engine efficiency trend and the proportionality between "motor" size and body size in animals and vehicles. These body-size effects are qualitatively the same as those uncovered earlier for the evolution of aircraft. The present study adds to this theoretical body of research the evolutionary design of all technologies [A. Bejan, The Physics of Life: The Evolution of Everything (St. Martin's Press, New York, 2016)].

  15. Anatomy of Scientific Evolution

    CERN Document Server

    Yun, Jinhyuk; Jeong, Hawoong

    2014-01-01

    The quest for historically impactful science and technology provides invaluable insight into the innovation dynamics of human society, yet many studies are limited to qualitative and small-scale approaches. Here, we investigate scientific evolution through systematic analysis of a massive corpus of digitized English texts between 1800 and 2008. Our analysis reveals remarkable predictability for long-prevailing scientific concepts based on the levels of their prior usage. Interestingly, once a threshold of early adoption rates is passed even slightly, scientific concepts can exhibit sudden leaps in their eventual lifetimes. We developed a mechanistic model to account for such results, indicating that slowly-but-commonly adopted science and technology surprisingly tend to have higher innate strength than fast-and-commonly adopted ones. The model prediction for disciplines other than science was also well verified. Our approach sheds light on unbiased and quantitative analysis of scientific evolution in society,...

  16. Education and Evolution

    DEFF Research Database (Denmark)

    Hjermitslev, Hans Henrik

    2015-01-01

    Herbert Spencer’s ideas were first introduced to a Scandinavian audience in the early 1870s when the Danish philosopher Harald Høffding published and lectured on his evolutionary philosophy. At this time, Høffding also played an important role in disseminating Charles Darwin’s theory of evolution...... among liberal philosophers, sociologists, educationalists and authors in Scandinavia, while his influence on Scandinavian naturalists remained limited. Scandinavian naturalists preferred their colleague Charles Darwin’s detailed empirical writings to the more philosophical perspective of Herbert Spencer...... and in discussing the philosophical consequences of an evolutionary worldview. In the late 1870s and 1880s several of Spencer’s works were translated into Danish and Swedish and he became a household name among liberal intellectuals who primarily discussed his views on education and evolution. His most influential...

  17. NLO properties of functionalized DNA thin films

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, Oksana [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)], E-mail: okrupka@mail.ru; El-ghayoury, Abdelkrim [University d' Angers, UFR Sciences, Laboratoire CIMMA UMR CNRS 6200, 2 Bd. Lavoisier, 49045 (France); Rau, Ileana; Sahraoui, Bouchta [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France); Grote, James G. [Air Force Research Laboratory Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, 3005 Hobson Way, Dayton, OH 45433-7707 (United States); Kajzar, Francois [University d' Angers, Laboratoire POMA CNRS UMR 6136, France, 2 Bd. Lavoisier, 49045 (France)

    2008-10-31

    In this paper we investigate the third-order nonlinear optical properties of spin deposited thin films of DNA-based complexes using the optical third harmonic generation (THG) technique at a fundamental wavelength of 1064 nm. We found that the third-order susceptibility, {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}), of DNA-based films was about one order of magnitude larger than that of our reference, a pure silica slab. In thin films doped with 5% of the chromophore disperse red 1 (DR1), a two order of magnitude larger value of {chi}{sup (3)}(- 3{omega};{omega},{omega},{omega}) was observed.

  18. Space Product Development of Commercial NLO Materials

    Science.gov (United States)

    Frazier, Donald O.; Paley, Mark S.; Penn, Benjamin G.; Abdeldayem, Hossin A.; Smith, David D.; Witherow, William K.

    1998-01-01

    Growth on selected substrates under various processing conditions have been useful for preparing highly oriented and otherwise promising films of organic compounds for optical thin films and waveguides. The significance of processing conditions to uniformity in thickness, degree of orientation, film quality, and optical properties for a specific processing technique is the general focus of work in this area. A study on the effect of processing conditions relevant to thin-film deposition by various techniques is particularly difficult because of the possibility that convection may play a major role in some cases. It is a goal of some researchers to produce good quality anisotropic films, therefore, an important, yet understudied, requirement should be to assess the role of gravity during certain processing methods. This may be particularly true for the vapor deposition of diacetylenes where subsequent polymerization in the crystal is topochemical and occurs readily only when neighboring monomer molecules are sufficiently close and suitably oriented. Likewise, this requirement is equally viable for the vapor deposition of certain materials such as Pcs in view of the results of microgravity experiments by 3M Corporation involving the preparation of thin films of copper Pc (CuPc). Microgravity-grown CuPc had several desirable features which indicate that the vapor growth of organic films in low-g may result in better quality films for optical and electrical applications. Indeed, other materials vapor deposited onto specific substrates in microgravity produce films potentially beneficial for electro-optic applications. A novel technique, recently discovered, for growing polydiacetylene thin films involves exposing a transparent substrate, in contact with diacetylene monomer solution, to ultraviolet (LTV) light. A polymer film deposits on the side of the substrate in contact with monomer in solution, and there are distinct gravitational effects, which influence film quality. Good quality thin films elude growth from solutions absent of uniform flow fields and homogeneous temperature distributions near the substrate surfaces. The flow fields and temperature distributions during the polymerization process by exposure to UV light details the nature of gravitational influences on this process.

  19. Entrepreneurship, Evolution and Geography

    OpenAIRE

    Stam, Erik

    2009-01-01

    Entrepreneurship is a fundamental driver of economic evolution. It is also a distinctly spatially uneven process, and thus an important explanation of the uneven economic development of regions and nations. Not surprisingly, entrepreneurship is a key element of evolutionary economics (Schumpeter 1934; Witt 1998; Grebel et al. 2003; Metcalfe 2004; Grebel 2007) and has been recognized as an important element in explaining (regional) economic development (Acs and Armington 2004; Audretsch et al....

  20. Software evolution and maintenance

    CERN Document Server

    Tripathy, Priyadarshi

    2014-01-01

    Software Evolution and Maintenance: A Practitioner's Approach is an accessible textbook for students and professionals, which collates the advances in software development and provides the most current models and techniques in maintenance.Explains two maintenance standards: IEEE/EIA 1219 and ISO/IEC14764Discusses several commercial reverse and domain engineering toolkitsSlides for instructors are available onlineInformation is based on the IEEE SWEBOK (Software Engineering Body of Knowledge)

  1. Evolution of Social networks

    OpenAIRE

    Hellmann, Tim; Staudigl, Mathias

    2012-01-01

    Modeling the evolution of networks is central to our understanding of modern large communication systems, such as theWorld-Wide-Web, as well as economic and social networks. The research on social and economic networks is truly interdisciplinary and the number of modeling strategies and concepts is enormous. In this survey we present some modeling approaches, covering classical random graph models and game-theoretic models, which may be used to provide a unified framework to model and analyze...

  2. Small asteroid system evolution

    OpenAIRE

    Jacobson, Seth A.

    2014-01-01

    Observations with radar, photometric and direct imaging techniques have discovered that multiple asteroid systems can be divided clearly into a handful of different morphologies, and recently, the discovery of small unbound asteroid systems called asteroid pairs have revolutionized the study of small asteroid systems. Simultaneously, new theoretical advances have demonstrated that solar radiation dictates the evolution of small asteroids with strong implications for asteroid internal structur...

  3. Viral quasispecies evolution

    OpenAIRE

    Domingo, Esteban; Sheldon, Julie; Perales, Celia

    2012-01-01

    Summary: Evolution of RNA viruses occurs through disequilibria of collections of closely related mutant spectra or mutant clouds termed viral quasispecies. Here we review the origin of the quasispecies concept and some biological implications of quasispecies dynamics. Two main aspects are addressed: (i) mutant clouds as reservoirs of phenotypic variants for virus adaptability and (ii) the internal interactions that are established within mutant spectra that render a virus ensemble the unit of...

  4. Small asteroid system evolution

    OpenAIRE

    Jacobson, Seth A.

    2014-01-01

    Observations with radar, photometric and direct imaging techniques have discovered that multiple asteroid systems can be divided clearly into a handful of different morphologies, and recently, the discovery of small unbound asteroid systems called asteroid pairs have revolutionized the study of small asteroid systems. Simultaneously, new theoretical advances have demonstrated that solar radiation dictates the evolution of small asteroids with strong implications for asteroid internal structur...

  5. Galactic Chemical Evolution

    CERN Document Server

    Gibson, B K; Renda, A; Kawata, D; Lee, H; Gibson, Brad K.; Fenner, Yeshe; Renda, Agostino; Kawata, Daisuke; Lee, Hyun-chul

    2003-01-01

    The primary present-day observables upon which theories of galaxy evolution are based are a system's morphology, dynamics, colour, and chemistry. Individually, each provides an important constraint to any given model; in concert, the four represent a fundamental (intractable) boundary condition for chemodynamical simulations. We review the current state-of-the-art semi-analytical and chemodynamical models for the Milky Way, emphasising the strengths and weaknesses of both approaches.

  6. ENVIRONMENT AND PROTOSTELLAR EVOLUTION

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yichen [Departamento de Astronomía, Universidad de Chile, Casilla 36-D, Santiago (Chile); Tan, Jonathan C., E-mail: yczhang.astro@gmail.com [Department of Astronomy, University of Florida, Gainesville, FL 32611 (United States)

    2015-04-01

    Even today in our Galaxy, stars form from gas cores in a variety of environments, which may affect the properties of the resulting star and planetary systems. Here, we study the role of pressure, parameterized via ambient clump mass surface density, on protostellar evolution and appearance, focusing on low-mass Sun-like stars and considering a range of conditions from relatively low pressure filaments in Taurus, to intermediate pressures of cluster-forming clumps like the Orion Nebula Cluster, to very high pressures that may be found in the densest infrared dark clouds or in the Galactic center. We present unified analytic and numerical models for the collapse of prestellar cores, accretion disks, protostellar evolution, and bipolar outflows, coupled with radiative transfer calculations and a simple astrochemical model to predict CO gas-phase abundances. Prestellar cores in high-pressure environments are smaller and denser and thus collapse with higher accretion rates and efficiencies, resulting in higher luminosity protostars with more powerful outflows. The protostellar envelope is heated to warmer temperatures, affecting infrared morphologies (and thus classification) and astrochemical processes like CO depletion onto dust grain ice mantles (and thus CO morphologies). These results have general implications for star and planet formation, especially via their effect on astrochemical and dust grain evolution during infall to and through protostellar accretion disks.

  7. Genome evolution of Oryza

    Directory of Open Access Journals (Sweden)

    Tieyan Liu

    2014-01-01

    Full Text Available The genus Oryza is composed of approximately 24 species. Wild species of Oryza contain a largely untapped resource of agronomically important genes. As an increasing number of genomes of wild rice species have been or will be sequenced, Oryza is becoming a model system for plant comparative, functional and evolutionary genomics studies. Comparative analyses of large genomic regions and whole-genome sequences have revealed molecular mechanisms involved in genome size variation, gene movement, genome evolution of polyploids, transition of euchromatin to heterochromatin and centromere evolution in the genus Oryza. Transposon activity and removal of transposable elements by unequal recombination or illegitimate recombination are two important factors contributing to expansion or contraction of Oryza genomes. Double-strand break repair mediated gene movement, especially non-homologous end joining, is an important source of non-colinear genes. Transition of euchromatin to heterochromatin is accompanied by transposable element amplification, segmental and tandem duplication of genic segments, and acquisition of heterochromatic genes from other genomic locations. Comparative analyses of multiple genomes dramatically improve the precision and sensitivity of evolutionary inference than single-genome analyses can provide. Further investigations on the impact of structural variation, lineage-specific genes and evolution of agriculturally important genes on phenotype diversity and adaptation in the genus Oryza should facilitate molecular breeding and genetic improvement of rice.

  8. Consciousness and biological evolution.

    Science.gov (United States)

    Lindahl, B I

    1997-08-21

    It has been suggested that if the preservation and development of consciousness in the biological evolution is a result of natural selection, it is plausible that consciousness not only has been influenced by neural processes, but has had a survival value itself; and it could only have had this, if it had also been efficacious. This argument for mind-brain interaction is examined, both as the argument has been developed by William James and Karl Popper and as it has been discussed by C.D. Broad. The problem of identifying mental phenomena with certain neural phenomena is also addressed. The main conclusion of the analysis is that an explanation of the evolution of consciousness in Darwinian terms of natural selection does not rule out that consciousness may have evolved as a mere causally inert effect of the evolution of the nervous system, or that mental phenomena are identical with certain neural phenomena. However, the interactionistic theory still seems, more plausible and more fruitful for other reasons brought up in the discussion.

  9. Evolution of segmented strings

    CERN Document Server

    Gubser, Steven S

    2016-01-01

    I explain how to evolve segmented strings in de Sitter and anti-de Sitter spaces of any dimension in terms of forward-directed null displacements. The evolution is described entirely in terms of discrete hops which do not require a continuum spacetime. Moreover, the evolution rule is purely algebraic, so it can be defined not only on ordinary real de Sitter and anti-de Sitter, but also on the rational points of the quadratic equations that define these spaces. For three-dimensional anti-de Sitter space, a simpler evolution rule is possible that descends from the Wess-Zumino-Witten equations of motion. In this case, one may replace three-dimensional anti-de Sitter space by a non-compact discrete subgroup of SL(2,R) whose structure is related to the Pell equation. A discrete version of the BTZ black hole can be constructed as a quotient of this subgroup. This discrete black hole avoids the firewall paradox by a curious mechanism: even for large black holes, there are no points inside the horizon until one reach...

  10. Thermodynamical Arguments Against Evolution

    Science.gov (United States)

    Rosenhouse, Jason

    2017-02-01

    The argument that the second law of thermodynamics contradicts the theory of evolution has recently been revived by anti-evolutionists. In its basic form, the argument asserts that whereas evolution implies that there has been an increase in biological complexity over time, the second law, a fundamental principle of physics, shows this to be impossible. Scientists have responded primarily by noting that the second law does not rule out increases in complexity in open systems, and since the Earth receives energy from the Sun, it is an open system. This reply is correct as far as it goes, and it adequately rebuts the most crude versions of the second law argument. However, it is insufficient against more sophisticated versions, and it leaves many relevant aspects of thermodynamics unexplained. We shall consider the history of the argument, explain the nuances various anti-evolution writers have brought to it, and offer thorough explanations for why the argument is fallacious. We shall emphasize in particular that the second law is best viewed as a mathematical statement. Since anti-evolutionists never make use of the mathematical structure of thermodynamics, invocations of the second law never contribute anything substantive to their discourse.

  11. Darwinian Evolution and Fractals

    Science.gov (United States)

    Carr, Paul H.

    2009-05-01

    Did nature's beauty emerge by chance or was it intelligently designed? Richard Dawkins asserts that evolution is blind aimless chance. Michael Behe believes, on the contrary, that the first cell was intelligently designed. The scientific evidence is that nature's creativity arises from the interplay between chance AND design (laws). Darwin's ``Origin of the Species,'' published 150 years ago in 1859, characterized evolution as the interplay between variations (symbolized by dice) and the natural selection law (design). This is evident in recent discoveries in DNA, Madelbrot's Fractal Geometry of Nature, and the success of the genetic design algorithm. Algorithms for generating fractals have the same interplay between randomness and law as evolution. Fractal statistics, which are not completely random, characterize such phenomena such as fluctuations in the stock market, the Nile River, rainfall, and tree rings. As chaos theorist Joseph Ford put it: God plays dice, but the dice are loaded. Thus Darwin, in discovering the evolutionary interplay between variations and natural selection, was throwing God's dice!

  12. Reconstructing human evolution

    CERN Document Server

    AUTHOR|(CDS)2074069

    1999-01-01

    One can reconstruct human evolution using modern genetic data and models based on the mathematical theory of evolution and its four major factors : mutation, natural selection, statistical fluctuations in finite populations (random genetic drift), and migration. Archaeology gives some help on the major dates and events of the process. Chances of studying ancient DNA are very limited but there have been a few successful results. Studying DNA instead of proteins, as was done until a few years ago, and in particular the DNA of mitochondria and of the Y chromosome which are transmitted, respectively, by the maternal line and the paternal line, has greatly simplified the analysis. It is now possible to carry the analysis on individuals, while earlier studies were of necessity based on populations. Also the evolution of ÒcultureÓ (i.e. what we learn from others), in particular that of languages, gives some help and can be greatly enlightened by genetic studies. Even though it is largely based on mechanisms of mut...

  13. Anmeldelse af Evolution, Literature and Film

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2011-01-01

    Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film......Diskussion af basisproblemer i evolutionær fiktionsteori med udgangspunkt i en anmeldelse af Evolution, Literature and Film...

  14. Experimental Evolution with Caenorhabditis Nematodes

    Science.gov (United States)

    Teotónio, Henrique; Estes, Suzanne; Phillips, Patrick C.; Baer, Charles F.

    2017-01-01

    The hermaphroditic nematode Caenorhabditis elegans has been one of the primary model systems in biology since the 1970s, but only within the last two decades has this nematode also become a useful model for experimental evolution. Here, we outline the goals and major foci of experimental evolution with C. elegans and related species, such as C. briggsae and C. remanei, by discussing the principles of experimental design, and highlighting the strengths and limitations of Caenorhabditis as model systems. We then review three exemplars of Caenorhabditis experimental evolution studies, underlining representative evolution experiments that have addressed the: (1) maintenance of genetic variation; (2) role of natural selection during transitions from outcrossing to selfing, as well as the maintenance of mixed breeding modes during evolution; and (3) evolution of phenotypic plasticity and its role in adaptation to variable environments, including host–pathogen coevolution. We conclude by suggesting some future directions for which experimental evolution with Caenorhabditis would be particularly informative. PMID:28592504

  15. Group selection in behavioral evolution.

    Science.gov (United States)

    Rachlin, Howard

    2017-09-09

    How may patterns of behavior change over an organism's lifetime? The answer is that they evolve (behavioral evolution) as species evolve over generations (biological evolution). In biological evolution, under certain conditions, groups of cooperative organisms would be selected over groups of non-cooperative organisms, even when cooperation imposes a cost to individuals. Analogously, in behavioral evolution, patterns of acts may be selected even when each individual act in the pattern is costly. Although there is considerable debate among biologists whether the conditions for group selection are met in biological evolution, it is argued here that they are met in behavioral evolution (as well as in cultural evolution). The article shows how selection of patterns can explain the learning of self-control and altruism. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Deep Inelastic Structure Functions at small x

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2006-01-01

    Explicit expressions for the non-singlet and singlet structure functions g_1 in the small-x region are obtained. They include the total resummation of the double- and single- logarithms of x and account for the running QCD coupling effects. Both the non-singlet and singlet structure functions are Regge behavied asymptotically, with the intercepts predicted in agreement with experiments. A detailed comparison with the DGLAP evolution equations for different values of x and Q^2 is performed. Finally, the role played by singular terms in DGLAP fits is discussed and explicitly shown to mimic the resummation of leading logarithms at small x.

  17. QCD running coupling effects for the non-singlet structure function at small x

    CERN Document Server

    Ermolaev, B I; Troyan, S I

    2000-01-01

    A generalization of the leading-order DGLAP evolution at small x is performed for the non-singlet structure function by resumming the leading-order DGLAP anomalous dimension to all orders in the QCD coupling. Explicit expressions are obtained for the non-singlet structure function of the deep inelastic scattering, taking into account both the double-logarithmic and the single-logarithmic contributions, including the running alpha_s effects. It is shown that when these contributions are included, the asymptotic small-x behaviour is power-like, with an exponent of about 0.4.

  18. Evolution before genes.

    Science.gov (United States)

    Vasas, Vera; Fernando, Chrisantha; Santos, Mauro; Kauffman, Stuart; Szathmáry, Eörs

    2012-01-05

    Our current understanding of evolution is so tightly linked to template-dependent replication of DNA and RNA molecules that the old idea from Oparin of a self-reproducing 'garbage bag' ('coacervate') of chemicals that predated fully-fledged cell-like entities seems to be farfetched to most scientists today. However, this is exactly the kind of scheme we propose for how Darwinian evolution could have occurred prior to template replication. We cannot confirm previous claims that autocatalytic sets of organic polymer molecules could undergo evolution in any interesting sense by themselves. While we and others have previously imagined inhibition would result in selectability, we found that it produced multiple attractors in an autocatalytic set that cannot be selected for. Instead, we discovered that if general conditions are satisfied, the accumulation of adaptations in chemical reaction networks can occur. These conditions are the existence of rare reactions producing viable cores (analogous to a genotype), that sustains a molecular periphery (analogous to a phenotype). We conclude that only when a chemical reaction network consists of many such viable cores, can it be evolvable. When many cores are enclosed in a compartment there is competition between cores within the same compartment, and when there are many compartments, there is between-compartment competition due to the phenotypic effects of cores and their periphery at the compartment level. Acquisition of cores by rare chemical events, and loss of cores at division, allows macromutation, limited heredity and selectability, thus explaining how a poor man's natural selection could have operated prior to genetic templates. This is the only demonstration to date of a mechanism by which pre-template accumulation of adaptation could occur.

  19. Evolution before genes

    Directory of Open Access Journals (Sweden)

    Vasas Vera

    2012-01-01

    Full Text Available Abstract Background Our current understanding of evolution is so tightly linked to template-dependent replication of DNA and RNA molecules that the old idea from Oparin of a self-reproducing 'garbage bag' ('coacervate' of chemicals that predated fully-fledged cell-like entities seems to be farfetched to most scientists today. However, this is exactly the kind of scheme we propose for how Darwinian evolution could have occurred prior to template replication. Results We cannot confirm previous claims that autocatalytic sets of organic polymer molecules could undergo evolution in any interesting sense by themselves. While we and others have previously imagined inhibition would result in selectability, we found that it produced multiple attractors in an autocatalytic set that cannot be selected for. Instead, we discovered that if general conditions are satisfied, the accumulation of adaptations in chemical reaction networks can occur. These conditions are the existence of rare reactions producing viable cores (analogous to a genotype, that sustains a molecular periphery (analogous to a phenotype. Conclusions We conclude that only when a chemical reaction network consists of many such viable cores, can it be evolvable. When many cores are enclosed in a compartment there is competition between cores within the same compartment, and when there are many compartments, there is between-compartment competition due to the phenotypic effects of cores and their periphery at the compartment level. Acquisition of cores by rare chemical events, and loss of cores at division, allows macromutation, limited heredity and selectability, thus explaining how a poor man's natural selection could have operated prior to genetic templates. This is the only demonstration to date of a mechanism by which pre-template accumulation of adaptation could occur. Reviewers This article was reviewed by William Martin and Eugene Koonin.

  20. Evolution of Sedimentary Rocks

    Science.gov (United States)

    Veizer, J.; MacKenzie, F. T.

    2003-12-01

    For almost a century, it has been recognized that the present-day thickness and areal extent of Phanerozoic sedimentary strata increase progressively with decreasing geologic age. This pattern has been interpreted either as reflecting an increase in the rate of sedimentation toward the present (Barrell, 1917; Schuchert, 1931; Ronov, 1976) or as resulting from better preservation of the younger part of the geologic record ( Gilluly, 1949; Gregor, 1968; Garrels and Mackenzie, 1971a; Veizer and Jansen, 1979, 1985).Study of the rocks themselves led to similarly opposing conclusions. The observed secular (=age) variations in relative proportions of lithological types and in chemistry of sedimentary rocks (Daly, 1909; Vinogradov et al., 1952; Nanz, 1953; Engel, 1963; Strakhov, 1964, 1969; Ronov, 1964, 1982) were mostly given an evolutionary interpretation. An opposing, uniformitarian, approach was proposed by Garrels and Mackenzie (1971a). For most isotopes, the consensus favors deviations from the present-day steady state as the likely cause of secular trends.This chapter attempts to show that recycling and evolution are not opposing, but complementary, concepts. It will concentrate on the lithological and chemical attributes of sediments, but not deal with the evolution of sedimentary mineral deposits (Veizer et al., 1989) and of life ( Sepkoski, 1989), both well amenable to the outlined conceptual treatment. The chapter relies heavily on Veizer (1988a) for the sections dealing with general recycling concepts, on Veizer (2003) for the discussion of isotopic evolution of seawater, and on Morse and Mackenzie (1990) and Mackenzie and Morse (1992) for discussion of carbonate rock recycling and environmental attributes.

  1. Evolution of sexual asymmetry

    Directory of Open Access Journals (Sweden)

    Hoekstra Rolf F

    2004-09-01

    Full Text Available Abstract Background The clear dominance of two-gender sex in recent species is a notorious puzzle of evolutionary theory. It has at least two layers: besides the most fundamental and challenging question why sex exists at all, the other part of the problem is equally perplexing but much less studied. Why do most sexual organisms use a binary mating system? Even if sex confers an evolutionary advantage (through whatever genetic mechanism, why does it manifest that advantage in two, and exactly two, genders (or mating types? Why not just one, and why not more than two? Results Assuming that sex carries an inherent fitness advantage over pure clonal multiplication, we attempt to give a feasible solution to the problem of the evolution of dimorphic sexual asymmetry as opposed to monomorphic symmetry by using a spatial (cellular automaton model and its non-spatial (mean-field approximation. Based on a comparison of the spatial model to the mean-field approximation we suggest that spatial population structure must have played a significant role in the evolution of mating types, due to the largely clonal (self-aggregated spatial distribution of gamete types, which is plausible in aquatic habitats for physical reasons, and appears to facilitate the evolution of a binary mating system. Conclusions Under broad ecological and genetic conditions the cellular automaton predicts selective removal from the population of supposedly primitive gametes that are able to mate with their own type, whereas the non-spatial model admits coexistence of the primitive type and the mating types. Thus we offer a basically ecological solution to a theoretical problem that earlier models based on random gamete encounters had failed to resolve.

  2. Evolution and human sexuality.

    Science.gov (United States)

    Gray, Peter B

    2013-12-01

    The aim of this review is to put core features of human sexuality in an evolutionary light. Toward that end, I address five topics concerning the evolution of human sexuality. First, I address theoretical foundations, including recent critiques and developments. While much traces back to Darwin and his view of sexual selection, more recent work helps refine the theoretical bases to sex differences and life history allocations to mating effort. Second, I consider central models attempting to specify the phylogenetic details regarding how hominin sexuality might have changed, with most of those models honing in on transitions from a possible chimpanzee-like ancestor to the slightly polygynous and long-term bonded sociosexual partnerships observed among most recently studied hunter-gatherers. Third, I address recent genetic and physiological data contributing to a refined understanding of human sexuality. As examples, the availability of rapidly increasing genomic information aids comparative approaches to discern signals of selection in sexuality-related phenotypes, and neuroendocrine studies of human responses to sexual stimuli provide insight into homologous and derived mechanisms. Fourth, I consider some of the most recent, large, and rigorous studies of human sexuality. These provide insights into sexual behavior across other national samples and on the Internet. Fifth, I discuss the relevance of a life course perspective to understanding the evolution of human sexuality. Most research on the evolution of human sexuality focuses on young adults. Yet humans are sexual beings from gestation to death, albeit in different ways across the life course, and in ways that can be theoretically couched within life history theory.

  3. Is evolution finished?

    Science.gov (United States)

    Davison, John A

    2004-01-01

    Since speciation seems to be no longer in progress, one is compelled to conclude that sexual reproduction is incompetent as a macroevolutionary device. I propose that the reason some might insist that evolution is still in progress stems primarily from the influence of two authorities, the geologist Charles Lyell, with his doctrine of uniformitarianism and Gregor Mendel, the discoverer of sexually mediated transmission genetics. William Bateson, the father of modern genetics, clearly foresaw the failure of Mendelism to explain macroevolutionary change, a perspective with which I am in full agreement.

  4. Demonstrating Supernova Remnant Evolution

    Science.gov (United States)

    Leahy, Denis A.; Williams, Jacqueline

    2017-01-01

    We have created a software tool to calculate at display supernova remnant evolution which includes all stages from early ejecta dominated phase to late-time merging with the interstellar medium. The software was created using Python, and can be distributed as Python code, or as an executable file. The purpose of the software is to demonstrate the different phases and transitions that a supernova remnant undergoes, and will be used in upper level undergraduate astrophysics courses as a teaching tool. The usage of the software and its graphical user interface will be demonstrated.

  5. Multitemporal conditional schema evolution

    DEFF Research Database (Denmark)

    Jensen, Ole Guttorm; Bøhlen, Michael Hanspeter

    2004-01-01

    Schema evolution is the ability of the database to respond to changes in the real world by allowing the schema to evolve.  The multidimensional conditionally evolving schema (MD-CES) is a conceptual model for conditional schema changes, which modify the schema of those tuples that satisfy...... the change condition.  The MD-CES is lossless and preserves schemas, but has an exponential space complexity.  In this paper we restrict conditional schema changes to timestamp attributes.  Specifically, we develop 1D-CES for schema versioning over one time dimension, and 2D-CES for schema versioning over...

  6. Evolution in the Multiverse

    CERN Document Server

    Standish, R K

    2000-01-01

    In the {\\em Many Worlds Interpretation} of quantum mechanics, the range of possible worlds (or histories) provides variation, and the Anthropic Principle is a selective principle analogous to natural selection. When looked on in this way, the ``process'' by which the laws and constants of physics is determined not too different from the process that gave rise to our current biodiversity, i.e. Darwinian evolution. This has implications for the fields of SETI and Artificial Life, which are based on a philosophy of the inevitability of life.

  7. Evolution of Trading strategies

    Science.gov (United States)

    Vicente, Javier

    2007-03-01

    We attempt to classify the trading strategies of agents in the London Stock Exchange into broad categories. Our study is based on that that identifies the member of the exchange associated with each transaction. Based on the evolution of the inventory (holdings of the stock) as a function of time, we use clustering methods to classify the strategies into several groups. We study how these groups evolve in time and attempt to correlate the membership of the groups with other market properties, such as price volatility.

  8. Evolution of galaxy habitability

    OpenAIRE

    Gobat, R.; Hong, S. E.

    2016-01-01

    We combine a semi-analytic model of galaxy evolution with constraints on circumstellar habitable zones and the distribution of terrestrial planets to probe the suitability of galaxies of different mass and type to host habitable planets, and how it evolves with time. We find that the fraction of stars with terrestrial planets in their habitable zone (known as habitability) depends only weakly on galaxy mass, with a maximum around 4e10 Msun. We estimate that 0.7% of all stars in Milky Way type...

  9. The Earth's early evolution.

    Science.gov (United States)

    Bowring, S A; Housh, T

    1995-09-15

    The Archean crust contains direct geochemical information of the Earth's early planetary differentiation. A major outstanding question in the Earth sciences is whether the volume of continental crust today represents nearly all that formed over Earth's history or whether its rates of creation and destruction have been approximately balanced since the Archean. Analysis of neodymium isotopic data from the oldest remnants of Archean crust suggests that crustal recycling is important and that preserved continental crust comprises fragments of crust that escaped recycling. Furthermore, the data suggest that the isotopic evolution of Earth's mantle reflects progressive eradication of primordial heterogeneities related to early differentiation.

  10. Plant domestication slows pest evolution.

    Science.gov (United States)

    Turcotte, Martin M; Lochab, Amaneet K; Turley, Nash E; Johnson, Marc T J

    2015-09-01

    Agricultural practices such as breeding resistant varieties and pesticide use can cause rapid evolution of pest species, but it remains unknown how plant domestication itself impacts pest contemporary evolution. Using experimental evolution on a comparative phylogenetic scale, we compared the evolutionary dynamics of a globally important economic pest - the green peach aphid (Myzus persicae) - growing on 34 plant taxa, represented by 17 crop species and their wild relatives. Domestication slowed aphid evolution by 13.5%, maintained 10.4% greater aphid genotypic diversity and 5.6% higher genotypic richness. The direction of evolution (i.e. which genotypes increased in frequency) differed among independent domestication events but was correlated with specific plant traits. Individual-based simulation models suggested that domestication affects aphid evolution directly by reducing the strength of selection and indirectly by increasing aphid density and thus weakening genetic drift. Our results suggest that phenotypic changes during domestication can alter pest evolutionary dynamics.

  11. Student Visual Communication of Evolution

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin

    2016-05-01

    Despite growing recognition of the importance of visual representations to science education, previous research has given attention mostly to verbal modalities of evolution instruction. Visual aspects of classroom learning of evolution are yet to be systematically examined by science educators. The present study attends to this issue by exploring the types of evolutionary imagery deployed by secondary students. Our visual design analysis revealed that students resorted to two larger categories of images when visually communicating evolution: spatial metaphors (images that provided a spatio-temporal account of human evolution as a metaphorical "walk" across time and space) and symbolic representations ("icons of evolution" such as personal portraits of Charles Darwin that simply evoked evolutionary theory rather than metaphorically conveying its conceptual contents). It is argued that students need opportunities to collaboratively critique evolutionary imagery and to extend their visual perception of evolution beyond dominant images.

  12. Toward Documentation of Program Evolution

    DEFF Research Database (Denmark)

    Vestdam, Thomas; Nørmark, Kurt

    2005-01-01

    The documentation of a program often falls behind the evolution of the program source files. When this happens it may be attractive to shift the documentation mode from updating the documentation to documenting the evolution of the program. This paper describes tools that support the documentation...... of program evolution. The tools are refinements of the Elucidative Programming tools, which in turn are inspired from Literate Programming tools. The version-aware Elucidative Programming tools are able to process a set of program source files in different versions together with unversioned documentation...... files. The paper introduces a set of fine grained program evolution steps, which are supported directly by the documentation tools. The automatic discovery of the fine grained program evolution steps makes up a platform for documenting coarse grained and more high-level program evolution steps...

  13. Student Visual Communication of Evolution

    Science.gov (United States)

    Oliveira, Alandeom W.; Cook, Kristin

    2017-06-01

    Despite growing recognition of the importance of visual representations to science education, previous research has given attention mostly to verbal modalities of evolution instruction. Visual aspects of classroom learning of evolution are yet to be systematically examined by science educators. The present study attends to this issue by exploring the types of evolutionary imagery deployed by secondary students. Our visual design analysis revealed that students resorted to two larger categories of images when visually communicating evolution: spatial metaphors (images that provided a spatio-temporal account of human evolution as a metaphorical "walk" across time and space) and symbolic representations ("icons of evolution" such as personal portraits of Charles Darwin that simply evoked evolutionary theory rather than metaphorically conveying its conceptual contents). It is argued that students need opportunities to collaboratively critique evolutionary imagery and to extend their visual perception of evolution beyond dominant images.

  14. Modeling Protein Evolution

    Science.gov (United States)

    Goldstein, Richard; Pollock, David

    The study of biology is fundamentally different from many other scientific pursuits, such as geology or astrophysics. This difference stems from the ubiquitous questions that arise about function and purpose. These are questions concerning why biological objects operate the way they do: what is the function of a polymerase? What is the role of the immune system? No one, aside from the most dedicated anthropist or interventionist theist, would attempt to determine the purpose of the earth's mantle or the function of a binary star. Among the sciences, it is only biology in which the details of what an object does can be said to be part of the reason for its existence. This is because the process of evolution is capable of improving an object to better carry out a function; that is, it adapts an object within the constraints of mechanics and history (i.e., what has come before). Thus, the ultimate basis of these biological questions is the process of evolution; generally, the function of an enzyme, cell type, organ, system, or trait is the thing that it does that contributes to the fitness (i.e., reproductive success) of the organism of which it is a part or characteristic. Our investigations cannot escape the simple fact that all things in biology (including ourselves) are, ultimately, the result of an evolutionary process.

  15. Ultrastructure, macromolecules, and evolution

    CERN Document Server

    Dillon, Lawrence S

    1981-01-01

    Thus far in the history of biology, two, and only two, fundamental principles have come to light that pervade and unify the entire science-the cell theory and the concept of evolution. While it is true that recently opened fields of inves­ tigation have given rise to several generalizations of wide impact, such as the universality of DNA and the energetic dynamics of ecology, closer inspection reveals them to be part and parcel of either of the first two mentioned. Because in the final analysis energy can act upon an organism solely at the cellular level, its effects may be perceived basically to represent one facet of cell me­ tabolism. Similarly, because the DNA theory centers upon the means by which cells build proteins and reproduce themselves, it too proves to be only one more, even though an exciting, aspect of the cell theory. In fact, if the matter is given closer scrutiny, evolution itself can be viewed as being a fundamental portion of the cell concept, for its effects arise only as a consequence ...

  16. Topology evolutions of silhouettes

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We give the topology changing of the silhouette in 3D space while others study the projections in an image. Silhouettes play a crucial role in visualization, graphics and vision. This work focuses on the global behaviors of silhouettes, especially their topological evolutions, such as splitting, merging, appearing and disappearing. The dynamics of silhouettes are governed by the topology, the curvature of the surface, and the view point. In this paper, we work on a more theoretical level to give enumerative properties of the silhouette including: the integration of signed geodesic curvature along a silhouette is equal to the view cone angle; in elliptic regions, no silhouette can be contained in another one; in hyperbolic regions, ifa silhouette is homotopic to a point, then it has at least 4 cusps; finally, critical events can only happen when the view point is on the aspect surfaces (ruled surface of the asymptotic lines of parabolic points with surface itself). We also introduce a method to visualize the evolution of silhouettes, especially all the critical events where the topologies of the silhouettes change. The results have broad applications in computer vision for recognition, graphics for rendering and visualization.

  17. Evolution of molecular clouds

    Science.gov (United States)

    Sevenster, M.

    1993-01-01

    The evolution of interstellar molecular hydrogen was studied, with a special interest for the formation and evolution of molecular clouds and star formation within them, by a two-dimensional hydrodynamical simulation performed on a rectangular grid of physical sizes on the order of 100 pc. It is filled with an initial density of approx. 1 cm(exp -3), except for one cell (approx. 1 pc(exp 2)) at the center of the grid where an accretion core of 1-10(exp 3) solar masses is placed. The grid is co-moving with the gridcenter that is on a circular orbit around the Galactic center and that also is the guiding center of epicyclic approximation of orbits of the matter surrounding it. The initial radial velocity is zero; to account for differential rotation the initial tangential velocity (i.e. the movement around the galactic center) is proportional to the radial distance to the grid center. The rate is comparable to the rotation rate at the Local Standard of Rest. The influence of galactic rotation is noticed by spiral or elliptical forms, but on much longer time scales than self gravitation and cooling processes. Density and temperature are kept constant at the boundaries and no inflow is allowed along the tangential boundaries.

  18. Evolution Of Cosmic Strings

    CERN Document Server

    Vanchurin, V

    2005-01-01

    We investigate the evolution of finite loops and infinite strings as a part of a complete cosmic string network. We give dynamical arguments showing that the structures on infinite strings should obey a scaling law. We perform a simulation of the network which uses functional forms for the string position and thus is exact to the limits of computer arithmetic. The effective box size of our simulation is at least two orders of magnitude larger than what was previously reached. Our results confirm that the wiggles on the strings obey a scaling law described by universal power spectrum. The average distance between long strings also scales accurately with the time. Production functions of string loops do not show scaling. With low intercommutation probability p the true scaling régime is not reached until very late cosmic times, which makes it difficult to simulate such evolutions. Via the expansion of the box technique, we were able to reach scaling with a wide range of p. The physical correlation ...

  19. Evolution in thermodynamics

    Science.gov (United States)

    Bejan, Adrian

    2017-03-01

    This review covers two aspects of "evolution" in thermodynamics. First, with the constructal law, thermodynamics is becoming the domain of physics that accounts for the phenomenon of evolution in nature, in general. Second, thermodynamics (and science generally) is the evolving add-on that empowers humans to predict the future and move more easily on earth, farther and longer in time. The part of nature that thermodynamics represents is this: nothing moves by itself unless it is driven by power, which is then destroyed (dissipated) during movement. Nothing evolves unless it flows and has the freedom to change its architecture such that it provides greater and easier access to the available space. Thermodynamics is the modern science of heat and work and their usefulness, which comes from converting the work (power) into movement (life) in flow architectures that evolve over time to facilitate movement. I also review the rich history of the science, and I clarify misconceptions regarding the second law, entropy, disorder, and the arrow of time, and the supposed analogy between heat and work.

  20. Evolution of Oxygenic Photosynthesis

    Science.gov (United States)

    Fischer, Woodward W.; Hemp, James; Johnson, Jena E.

    2016-06-01

    The origin of oxygenic photosynthesis was the most important metabolic innovation in Earth history. It allowed life to generate energy and reducing power directly from sunlight and water, freeing it from the limited resources of geochemically derived reductants. This greatly increased global primary productivity and restructured ecosystems. The release of O2 as an end product of water oxidation led to the rise of oxygen, which dramatically altered the redox state of Earth's atmosphere and oceans and permanently changed all major biogeochemical cycles. Furthermore, the biological availability of O2 allowed for the evolution of aerobic respiration and novel biosynthetic pathways, facilitating much of the richness we associate with modern biology, including complex multicellularity. Here we critically review and synthesize information from the geological and biological records for the origin and evolution of oxygenic photosynthesis. Data from both of these archives illustrate that this metabolism first appeared in early Paleoproterozoic time and, despite its biogeochemical prominence, is a relatively late invention in the context of our planet's history.