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Title:

Generalized parton distributions in proton-proton collisions at LHC

Description:

Generalized parton distributions (GPDs) describe the distributions of quarks and gluons in the proton with respect to both longitudinal momentum and transverse position. The transverse spatial distributions of partons can be extracted from measurements of the t-dependence of hard exclusive processes in e-p scattering, such as J/psi photoproducti...

Generalized parton distributions (GPDs) describe the distributions of quarks and gluons in the proton with respect to both longitudinal momentum and transverse position. The transverse spatial distributions of partons can be extracted from measurements of the t-dependence of hard exclusive processes in e-p scattering, such as J/psi photoproduction at HERA (gluons). This information is an important ingredient in the theory of high-energy p-p collisions with hard QCD processes (dijets, Higgs boson production). We summarize recent results obtained from applying these ideas to (a) inclusive p-p scattering (hard processes as a trigger on central collisions, approach to the unitarity limit), (b) diffractive p-p scattering (rapidity gap survival, Higgs boson search at LHC). We also comment on the possibilities of using high-energy p-p scattering with hard processes as a means to ''measure'' the GPDs, complementing the information obtained from e-p scattering. Minimize

Year of Publication:

2008-02-05

Subjects:

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; GLUONS; HIGGS BOSONS; LONGITUDINAL MOMENTUM; PARTICLE RAPIDITY; PHOTOPRODUCTION; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; QUARKS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; GLUONS; HIGGS BOSONS; LONGITUDINAL MOMENTUM; PARTICLE RAPIDITY; PHOTOPRODUCTION; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; QUARKS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY Minimize

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530 Physics *(computed)*

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Title:

Thinning operations for modeling time series of counts—a survey

Description:

Thinning operations, Binomial thinning, Count time series, INAR(1) models

Thinning operations, Binomial thinning, Count time series, INAR(1) models Minimize

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article

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Title:

StatSoft, Inc., Tulsa, OK.: STATISTICA, Version 8

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article

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Title:

Modelling time series of counts with overdispersion

Description:

Time series of counts, INGARCH model, ACP model, Overdispersion, Autocorrelation structure

Time series of counts, INGARCH model, ACP model, Overdispersion, Autocorrelation structure Minimize

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article

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Title:

Monitoring correlated processes with binomial marginals

Description:

Few approaches for monitoring autocorrelated attribute data have been proposed in the literature. If the marginal process distribution is binomial, then the binomial AR(1) model as a realistic and well-interpretable process model may be adequate. Based on known and newly derived statistical properties of this model, we shall develop approaches t...

Few approaches for monitoring autocorrelated attribute data have been proposed in the literature. If the marginal process distribution is binomial, then the binomial AR(1) model as a realistic and well-interpretable process model may be adequate. Based on known and newly derived statistical properties of this model, we shall develop approaches to monitor a binomial AR(1) process, and investigate their performance in a simulation study. A case study demonstrates the applicability of the binomial AR(1) model and of the proposed control charts to problems from statistical process control. ; binomial AR(1) models, statistical process control, control charts, case study Minimize

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article

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Title:

Detecting mean increases in Poisson INAR(1) processes with EWMA control charts

Description:

Processes of serially dependent Poisson counts are commonly observed in real-world applications and can often be modeled by the first-order integer-valued autoregressive (INAR) model. For detecting positive shifts in the mean of a Poisson INAR(1) process, we propose the one-sided s exponentially weighted moving average (EWMA) control chart, whic...

Processes of serially dependent Poisson counts are commonly observed in real-world applications and can often be modeled by the first-order integer-valued autoregressive (INAR) model. For detecting positive shifts in the mean of a Poisson INAR(1) process, we propose the one-sided s exponentially weighted moving average (EWMA) control chart, which is based on a new type of rounding operation. The s-EWMA chart allows computing average run length (ARLs) exactly and efficiently with a Markov chain approach. Using an implementation of this procedure for ARL computation, the s-EWMA chart is easily designed, which is demonstrated with a real-data example. Based on an extensive study of ARLs, the out-of-control performance of the chart is analyzed and compared with that of a c chart and a one-sided cumulative sum (CUSUM) chart. We also investigate the robustness of the chart against departures from the assumed Poisson marginal distribution. ; Poisson INAR(1) model, s-EWMA chart, c chart, CUSUM chart, ARL performance, Markov chain approach, robustness Minimize

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Title:

Qadhat—a comparative study of ancient and new lime mortar from the Marib province/Yemen

Description:

Qadhat is the name for a lime mortar in Southern Arabia. Its usage has a long tradition. This work describes physical and mineralogical properties of ancient, historical and new samples, which seem to have been produced the same way. XRD, thin sections and SEM analyses show the similarity of the material. It consists of aggregates of volcanic ma...

Qadhat is the name for a lime mortar in Southern Arabia. Its usage has a long tradition. This work describes physical and mineralogical properties of ancient, historical and new samples, which seem to have been produced the same way. XRD, thin sections and SEM analyses show the similarity of the material. It consists of aggregates of volcanic material that are rich in volcanic glass and lime as binder. The production process includes several hours of crushing the material, which produces fine-grained splinters of aggregates in the binder matrix and gives the mortar a high stability. A weathering test with sodium sulphate on different samples confirms that the stability of this mortar is the result of the production process. Minimize

Publisher:

Springer-Verlag

Year of Publication:

2009-07-01

Source:

Archaeological and Anthropological Sciences, 2009-07-01, Volume 1, pp 87-94

Archaeological and Anthropological Sciences, 2009-07-01, Volume 1, pp 87-94 Minimize

Document Type:

Original Paper

Language:

En

Subjects:

Qadhat ; Lime mortar ; Mortar ; Volcanic material ; Binder matrix

Qadhat ; Lime mortar ; Mortar ; Volcanic material ; Binder matrix Minimize

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Title:

The black-disk limit in high-energy ep and pp scattering

Description:

We review a recently proposed framework for studying the approach to the unitarity limit in small-x processes in ep and pp scattering within the DGLAP approximation. Our formulation is based on the correspondence between the standard QCD factorization theorems for hard processes and the dipole picture of small-x scattering in the leading logarit...

We review a recently proposed framework for studying the approach to the unitarity limit in small-x processes in ep and pp scattering within the DGLAP approximation. Our formulation is based on the correspondence between the standard QCD factorization theorems for hard processes and the dipole picture of small-x scattering in the leading logarithmic approximation. It allows us to incorporate information about the transverse spatial distribution of gluons in the proton from exclusive vector meson production at HERA. We show that the interaction of small-size color singlet configurations with the proton approaches the ''black-disk limit'' (BDL) due to the growth of the DGLAP gluon density at small x. This new dynamical regime is marginally visible in diffractive DIS at HERA, and will be fully reached in central pp collisions at LHC. Minimize

Year of Publication:

2008-02-05

Subjects:

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; COLOR; DIPOLES; FACTORIZATION; GLUONS; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY; VECTOR MESONS

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; COLOR; DIPOLES; FACTORIZATION; GLUONS; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY; VECTOR MESONS Minimize

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530 Physics *(computed)*

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Title:

Higher twists in polarized DIS and the size of the constituent quark

Description:

The spontaneous breaking of chiral symmetry implies the presence of a short-distance scale in the QCD vacuum, which phenomenologically may be associated with the ''size'' of the constituent quark, rho {approx} 0.3 fm. We discuss the role of this scale in the matrix elements of the twist-4 and 3 quark-gluon operators determining the leading power...

The spontaneous breaking of chiral symmetry implies the presence of a short-distance scale in the QCD vacuum, which phenomenologically may be associated with the ''size'' of the constituent quark, rho {approx} 0.3 fm. We discuss the role of this scale in the matrix elements of the twist-4 and 3 quark-gluon operators determining the leading power (1/Q{sup 2}-) corrections to the moments of the nucleon spin structure functions. We argue that the flavor-nonsinglet twist-4 matrix element, f{sub 2}{sup u-d}, has a sizable negative value of the order rho{sup -2}, due to the presence of sea quarks with virtualities {approx} rho{sup -2} in the proton wave function. The twist-3 matrix element, d{sub 2}, is not related to the scale rho{sup -2}. Our arguments support the results of previous calculations of the matrix elements in the instanton vacuum model. We show that this qualitative picture is in agreement with the phenomenological higher-twist correction extracted from an NLO QCD fit to the world data on g{sub 1}{sup p} and g{sub 1}{sup n}, which include recent data from the Jefferson Lab Hall A and COMPASS experiments. We comment on the implications of the short-distance scale rho for quark-hadron duality and the x-dependence of higher-twist contributions. Minimize

Year of Publication:

2009-12-16

Subjects:

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; CHIRAL SYMMETRY; DUALITY; INSTANTONS; MATRIX ELEMENTS; NUCLEONS; PROTONS; QUANTUM CHROMODYNAMICS; QUARKS; SEAS; SPIN; STRUCTURE FUNCTIONS; WAVE FUNCTIONS

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; CHIRAL SYMMETRY; DUALITY; INSTANTONS; MATRIX ELEMENTS; NUCLEONS; PROTONS; QUANTUM CHROMODYNAMICS; QUARKS; SEAS; SPIN; STRUCTURE FUNCTIONS; WAVE FUNCTIONS Minimize

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530 Physics *(computed)*

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Title:

The black-disk limit in high-energy ep and pp scattering

Description:

We review a recently proposed framework for studying the approach to the unitarity limit in small-x processes in ep and pp scattering within the DGLAP approximation. Our formulation is based on the correspondence between the standard QCD factorization theorems for hard processes and the dipole picture of small-x scattering in the leading logarit...

We review a recently proposed framework for studying the approach to the unitarity limit in small-x processes in ep and pp scattering within the DGLAP approximation. Our formulation is based on the correspondence between the standard QCD factorization theorems for hard processes and the dipole picture of small-x scattering in the leading logarithmic approximation. It allows us to incorporate information about the transverse spatial distribution of gluons in the proton from exclusive vector meson production at HERA. We show that the interaction of small-size color singlet configurations with the proton approaches the ''black-disk limit'' (BDL) due to the growth of the DGLAP gluon density at small x. This new dynamical regime is marginally visible in diffractive DIS at HERA, and will be fully reached in central pp collisions at LHC. Minimize

Year of Publication:

2008-02-05

Subjects:

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; COLOR; DIPOLES; FACTORIZATION; GLUONS; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY; VECTOR MESONS

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS ; GENERAL PHYSICS; COLOR; DIPOLES; FACTORIZATION; GLUONS; PRODUCTION; PROTONS; QUANTUM CHROMODYNAMICS; SCATTERING; SPATIAL DISTRIBUTION; UNITARITY; VECTOR MESONS Minimize

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530 Physics *(computed)*

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