High energy physics - phenomenology

Quark spin content of the proton, hyperon semileptonic decays, and the decay width of the Theta[sup +] pentaquark

Ghil-Seok Yang, Hyun-Chul Kim, and Klaus Goeke
Using the exisiting experimental data for hyperon semileptonic decays and the flavor-singlet axial-vector charge g[sub A][sup (0)] from polarized deep inelastic scattering of the proton, we derive the decay width of the Theta[sup +] pentaquark baryon. We take into account the effects of flavor SU(3) ... [Phys. Rev. D 75, 094004 (2007)] published Thu May 3, 2007.

Measurements of CP-Violating Asymmetries in B[sup 0] --> a[sub 1][sup [plus-minus]](1260)pi[sup -/+] Decays

B. Aubert, M. Bona, D. Boutigny, Y. Karyotakis, J. P. Lees et al. BABAR Collaboration
We present measurements of CP-violating asymmetries in the decay B[sup 0]-->a[sub 1][sup [plus-minus]](1260)pi[sup -/+] with a[sub 1][sup [plus-minus]](1260)-->pi[sup -/+]pi[sup ]pi[sup ]. The data sample corresponds to 384 x 10[sup 6] B[overline B] pairs collected with the BABAR detector at the PEP ... [Phys. Rev. Lett. 98, 181803 (2007)] published Wed May 2, 2007.

Constraints on Braneworld Gravity Models from a Kinematic Limit on the Age of the Black Hole XTE J1118 + 480

Dimitrios Psaltis
In braneworld gravity models with a finite antide Sitter space (AdS) curvature in the extra dimension, the AdS/conformal field theory correspondence leads to a prediction for the lifetime of astrophysical black holes that is significantly smaller than the Hubble time, for asymptotic curvatures that ... [Phys. Rev. Lett. 98, 181101 (2007)] published Wed May 2, 2007.

Generalized parton distributions from hadronic observables: Zero skewness

Saeed Ahmad, Heli Honkanen, Simonetta Liuti, and Swadhin K. Taneja
We propose a physically motivated parametrization for the unpolarized generalized parton distributions. At zero value of the skewness variable, zeta, the parametrization is constrained by simultaneously fitting the experimental data on both the nucleon elastic form factors and the deep inelastic str ... [Phys. Rev. D 75, 094003 (2007)] published Wed May 2, 2007.

Revising limits on neutrino-Majoron couplings

A. P. Lessa and O. L. G. Peres
Any theory that has a global spontaneously broken symmetry will imply the existence of very light neutral bosons or massless bosons (sometimes called Majorons). For most of these models we have neutrino-Majoron couplings that appear as additional branching ratios in decays of mesons and leptons. Her ... [Phys. Rev. D 75, 094001 (2007)] published Tue May 1, 2007.

Azimuthal and single-spin asymmetry in deep-inelastic lepton-nucleon scattering

Zuo-tang Liang and Xin-Nian Wang
We derive a general framework for describing semi-inclusive deep-inelastic lepton-nucleon scattering in terms of the unintegrated parton distributions and other higher-twist parton correlations. Such a framework provides a consistent approach to the calculation of inclusive and semi-inclusive cross ... [Phys. Rev. D 75, 094002 (2007)] published Tue May 1, 2007.

Partial-Wave Analysis of Single-Pion Production Reactions

R. A. Arndt, W. J. Briscoe, I. I. Strakovsky, and R. L. Workman
We present an overview of our efforts to analyze pion-nucleon elastic scattering data, along with data from related photo- and electroproduction reactions, in order to study the baryon spectrum. We then focus on the Delta(1232) resonance. Fits to pion photo- and electroproduction data have been used ... [AIP Conf. Proc. 904, 269 (2007)] published Mon Apr 30, 2007.

Multipole Extraction: A Novel, Model Independent Method

E. Stiliaris and C. N. Papanicolas
A novel method for extracting multipole amplitudes in the nucleon resonance region from electroproduction data is presented. The method is based on statistical concepts and it relies heavily on Monte Carlo and simulation techniques; it produces precise identification and determination of the contrib ... [AIP Conf. Proc. 904, 257 (2007)] published Mon Apr 30, 2007.

Accuracy of Extracted Multipoles from gamma *N --> Delta Data

S. Stave, A. M. Bernstein, and I. Nakagawa
This work evaluates the model dependence of the electric and Coulomb quadrupole amplitudes (E2, C2) in the predominantly M1 (magnetic dipole-quark spin flip) gamma*N --> Delta transition. Both the model-to-model dependence and the intrinsic model uncertainties are evaluated and found to be comparabl ... [AIP Conf. Proc. 904, 245 (2007)] published Mon Apr 30, 2007.

gamma * N --> Delta at JLab: Exploring the High Q[sup 2] Regime

Maurizio Ungaro, Kyungseon Joo, and Paul Stoler
We report a new measurement of the exclusive electroproduction reaction gamma* p --> pi[sup 0] p to explore the evolution from soft non-perturbative physics to hard processes via the Q[sup 2] dependence of the magnetic (M[sub 1+]), electric (E[sub 1+]) and scalar (S[sub 1+]) multipoles in the N --> ... [AIP Conf. Proc. 904, 232 (2007)] published Mon Apr 30, 2007.

Exploring the gamma * p --> Delta(1232) Transition at Low Q[sup 2] Using CLAS

L. C. Smith CLAS Collaboration
Precision measurements of the p(e, e[prime] p)pi[sup 0] reaction were performed using the CEBAF Large Acceptance Spectrometer (CLAS) in the range of photon invariant momentum transfer Q[sup 2] = 0.16 0.36 GeV[sup 2]. Fits to the data using both a Unitary Isobar Model and the Sato-Lee dynamical mode ... [AIP Conf. Proc. 904, 222 (2007)] published Mon Apr 30, 2007.

Nucleon Form Factor Experiments and the Pion Cloud

Kees de Jager
The experimental and theoretical status of elastic electron scattering from the nucleon is reviewed. A wealth of new data of unprecedented precision, especially at small values of the momentum transfer, in parallel to new theoretical insights, has allowed sensitive tests of the influence of the pion ... [AIP Conf. Proc. 904, 95 (2007)] published Mon Apr 30, 2007.

Search for Quadrupole Amplitudes in the N --> Delta Transition at Bates and Mainz

N. F. Sparveris
The issue of hadron deformation has been a subject of intense scientific interest during the last two decades. The detailed study of the N --> Delta transition has emerged as the prefered method of experimental investigation of this issue. A brief overview of the experimental and theoretical landsca ... [AIP Conf. Proc. 904, 213 (2007)] published Mon Apr 30, 2007.

Real Photon Experiments: N --> Delta and mu (Delta)

Martin Kotulla
The electromagnetic structure of the Delta[sup +]1232 resonance has been investigated in photoproduction experiments. In the first part, the status on the E2/M1 ratio is reported where new data allowed for an extraction of R[sub EM] = (2.4 0.16[sub stat] 0.24[sub sys]). In the second part, the rad ... [AIP Conf. Proc. 904, 203 (2007)] published Mon Apr 30, 2007.

Nucleon Resonance Excitation with Virtual Photons

L. Tiator and S. Kamalov
The unitary isobar model MAID is used for a partial wave analysis of pion photoproduction and electroproduction data on the nucleon. In particular we have taken emphasis on the region of the Delta(1232) resonance and have separated the resonance and background amplitudes with the K-matrix approach. ... [AIP Conf. Proc. 904, 191 (2007)] published Mon Apr 30, 2007.

Phenomenological Hadron Form Factors: Shape and Relativity

B. Julia-Diaz
The use of relativistic quark models with simple parametric wave functions for the understanding of the electromagnetic structure of nucleons together with their electromagnetic transition to resonances is discussed. The implications of relativity in the different ways it can be implemented in a sim ... [AIP Conf. Proc. 904, 167 (2007)] published Mon Apr 30, 2007.

The gamma N --> Delta Transition in Chiral Effective-field Theory

Vladimir Pascalutsa and Marc Vanderhaeghen
We describe the pion electroproduction processes in the Delta(1232)-resonance region within the framework of chiral effective-field theory. By studying the observables of pion electroproduction in a next-to-leading order calculation we are able to make predictions and draw conclusions on the propert ... [AIP Conf. Proc. 904, 158 (2007)] published Mon Apr 30, 2007.

Overview of Dynamic Models for gamma N --> Delta

D. Drechsel and L. Tiator
We present an overview of dynamic and related models for pion electroproduction on the nucleon due to Delta(1232) excitation. The electromagnetic multipoles and their ratios obtained from these models and from effective field theories are compared, and the existing contradictory results for the pion ... [AIP Conf. Proc. 904, 129 (2007)] published Mon Apr 30, 2007.

Charge Form Factors and Nucleon Shape

A. J. Buchmann
To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the proton's charge density. Quark model relations are employed to derive ... [AIP Conf. Proc. 904, 110 (2007)] published Mon Apr 30, 2007.

Virtual Compton Scattering and the Pion Contribution

Rory Miskimen
Recent results from a virtual Compton scattering experiment performed at the MIT-Bates out-of-plane scattering facility are presented. In this experiment the mean square polarizability radii of the proton have been measured for the first time The response functions, P[sub LL]- P[sub TT]/epsilon and ... [AIP Conf. Proc. 904, 104 (2007)] published Mon Apr 30, 2007.

N-flationary Magnetic Fields

Mohamed M. Anber and Lorenzo Sorbo
There is increasing interest in the role played by pseudo Nambu-Goldstone bosons (pNGBs) in the construction of string-inspired models of inflation. In these models the inflaton is expected to be coupled to gauge fields, and will lead to the generation of magnetic fields that can be of cosmological ... [AIP Conf. Proc. 903, 669 (2007)] published Fri Apr 27, 2007.

New Discrete States in Supersymmetric c = 1 Model

Dimitri Polyakov
Two-dimensional string theory is known to contain the set of discrete states that are the SU(2) multiplets generated by the lowering operator of the SU(2) current algebra. Their structure constants are defined by the area preserving diffeomorphisms in two dimensions. In this talk I show that the int ... [AIP Conf. Proc. 903, 541 (2007)] published Fri Apr 27, 2007.

Patterns of Supersymmetry Breaking in Moduli-mixing Racetrack Model

Hiroyuki Abe
We show some structures of moduli stabilization and supersymmetry breaking caused by gaugino condensations with the gauge couplings depending on two moduli which often appear in the four-dimensional effective theories of superstring compactifications. (C)2007 American Institute of Physics ... [AIP Conf. Proc. 903, 517 (2007)] published Fri Apr 27, 2007.

Floating Correlations on the String Landscape

Keith R. Dienes and Michael Lennek
The realization that string theory gives rise to a huge landscape of vacuum solutions has recently prompted a statistical approach towards extracting phenomenological predictions from string theory. Unfortunately, for most classes of string models, direct enumeration of all solutions is not computat ... [AIP Conf. Proc. 903, 505 (2007)] published Fri Apr 27, 2007.

Hawking radiation of mini black holes at colliders: Determination of BH evolution

Daisuke Ida, Kin-ya Oda, and Seong Chan Park
In the series of papers by Ida, Oda and Park, the complete description of Hawking radiation to the brane localized Standard model fields from mini black holes in the low energy gravity scenarios are obtained. In this proceedings, we briefly review what we have learned in those papers. (C)2007 Americ ... [AIP Conf. Proc. 903, 471 (2007)] published Fri Apr 27, 2007.

A Direct ILC Measurement of W-t-b

Puneet Batra
We propose the first direct measurement of the Standard Model W-t-b coupling at the ILC, from measurements of tt-bar -like signals below the tt-bar production threshold. We estimate that the ILC with 100 fb[sup 1] can measure a combination of the coupling and top width to high precision, and when c ... [AIP Conf. Proc. 903, 459 (2007)] published Fri Apr 27, 2007.

The SUSY Flavor Problem, Proton Decay and Discrete Family Symmetry

Etsuko Itou, Yuji Kajiyama, and Jisuke Kubo
We consider a supersymmetric extension of the standard model, which possess a family symmetry based on a binary dihedral group Q[sub 6], and investigate the consequences of the family symmetry on the mixing of fermions, FCNCs and the stability of proton. (C)2007 American Institute of Physics ... [AIP Conf. Proc. 903, 389 (2007)] published Fri Apr 27, 2007.

Is there a new weakly interacting boson of mass 214 MeV?

N. G. Deshpande, G. Eilam, and J. Jiang
We consider the existence of the stated X[sup 0] (214 MeV) in Sigma[sup +] --> p[mu][sup +][mu][sup ] decay found by the HyperCP collaboration. We assume that a fundamental spin zero boson X[sup 0] coupled to quarks leads to flavor changing s --> dX[sup 0] process. We estimate the scalar and pseudos ... [AIP Conf. Proc. 903, 319 (2007)] published Fri Apr 27, 2007.

Shortcuts in extra dimensions and neutrino physics

Heinrich Pas, Sandip Pakvasa, and Thomas J. Weiler
We discuss the possibility of sterile neutrinos taking shortcuts in extra dimensions, and the consequences for neutrino oscillations. This effect influences the active-sterile neutrino mixing and provides a possibility to accommodate the LSND evidence for neutrino oscillations together with bounds f ... [AIP Conf. Proc. 903, 315 (2007)] published Fri Apr 27, 2007.

Precision Observables in the MSSM: W mass and the muon magnetic moment

J. Haestier, S. Heinemeyer, W. Hollik, D. Stockinger, A. M. Weber et al.
The precision observables M[sub W] and g 2 of the muon are discussed in the framework of the MSSM. Recent progress in the evaluation of the theoretical predictions is described, and the MSSM predictions are compared with the SM predictions and the experimental values. (C)2007 American Institute of ... [AIP Conf. Proc. 903, 291 (2007)] published Fri Apr 27, 2007.

Model Independent Naturalness Bounds on Magnetic Moments of Majorana Neutrinos

Mikhail Gorchtein, Nicole F. Bell, Michael J. Ramsey-Musolf, Petr Vogel, and Peng Wang
We analyze the implications of neutrino masses for the magnitude of neutrino magnetic moments. By considering electroweak radiative corrections to the neutrino mass, we derive model-independent naturalness upper bounds on neutrino magnetic moments, generated by physics above the electroweak scale. F ... [AIP Conf. Proc. 903, 287 (2007)] published Fri Apr 27, 2007.

Probing Extra Dimensions with ATLAS

Dominik Dannheim
In the late nineties several authors suggested that the extra dimensions predicted by string theory might lead to observable effects at high energy colliders. The ATLAS experiment which will start taking data at the LHC in 2007 will be an excellent place to search for such effects. The sensitivity o ... [AIP Conf. Proc. 903, 261 (2007)] published Fri Apr 27, 2007.

Z + Jets Cross Section Ratio Measurements

Marc Buehler
We present a study of events with Z bosons and jets produced at the Fermilab Tevatron Collider in pp-bar collisions at a center of mass energy of 1.96 TeV. The data sample consists of nearly 14,000 Z/gamma[sup *] --> e[sup +]e[sup ] candidates corresponding to the integrated luminosity of 340 pb[su ... [AIP Conf. Proc. 903, 153 (2007)] published Fri Apr 27, 2007.

Measurement of the Longitudinal Structure Function from ep Collisions with the H1 Detector at HERA

N. Raičević H1 collaboration
The longitudinal structure function, F[sub L], is identically zero in lowest order QCD, but due to gluon radiation gets a non-zero value in perturbative QCD. Measurements of F[sub L] can thus provide constraints on the gluon density in the proton which are complementary to that obtained from the sca ... [AIP Conf. Proc. 899, 575 (2007)] published Fri Apr 27, 2007.

WW Production at the LHC in NLO Simulations

N. Vranješ, Lj. Simić, D. Reljić, D. Vudragović, and D. S. Popović
The WW production via leptonic decay is studied using next-to-leading order generators. The output from the Baur, Han and Ohnemus (BHO) NLO code is compared with MC@NLO generator. (C)2007 American Institute of Physics ... [AIP Conf. Proc. 899, 225 (2007)] published Fri Apr 27, 2007.

Measurement of the Inclusive ep Deep Inelastic Scattering Cross Section at Low Q[sup 2] with the H1 Detector at HERA

N. Raičević H1 collaboration
The focus of this report are the recent measurements of the cross section and proton structure function F[sub 2] in ep deep inelastic scattering (DIS) at low virtuality of the exchanged boson, Q[sup 2], with the H1 detector at the HERA accelerator in Hamburg. The region of low Q[sup 2] and low Bjork ... [AIP Conf. Proc. 899, 217 (2007)] published Fri Apr 27, 2007.

High Energy Photon Beam Generation For QCD Explorer Based gamma P Colliders

A. K. Ciftci, H. Aksakal, and Z. Nergiz
Combination of two linear accelerator projects, namely CLIC (Compact Linear Collider) and ILC (International Linear Collider) with LHC(Large Hadron Collider) offer an opportunity to build gammap collider. High energy photons are produced by the Compton backscattering of the laser photons off high en ... [AIP Conf. Proc. 899, 211 (2007)] published Fri Apr 27, 2007.

Recent results of the NA48/2 experiment

Evelina Marinova NA48 CERN collaboration
The main goals of the NA48/2 experiment are a search for direct CP violation in the charged kaon decays, a measurement of the pion scattering lengths using Ke4 decays and an investigation of some rare decays. By using large samples of K[sup ] --> pi[sup ]pi[sup +]pi[sup ] and K[sup ] --> pi[sup ]pi ... [AIP Conf. Proc. 899, 205 (2007)] published Fri Apr 27, 2007.

Pion production in p + C collisions at 158 GeV/c beam momentum

M. Makariev NA49 Collaboration
The production of charged pions in minimum bias p+C collisions at 158 GeV/c beam momentum has been studied. A data sample of 377 000 inelastic events were obtained with NA49 detector at CERN SPS. The data cover large phase space ranging from 0 to 1.8 GeV/c in transverse momentum and from 0.1 to 0.5 ... [AIP Conf. Proc. 899, 203 (2007)] published Fri Apr 27, 2007.

Investigations of Semileptonic Kaon Decays at the NA48 Experiment

Milena Dyulendarova NA48 Collaboration
Semileptonic decays of charged and neutral kaons, K[sub L] --> pi[sup ]e[sup -/+]nu[sub e] (K[sub e3][sup 0]), K[sub L] --> pi[sup ][mu][sup -/+]nu[sub [mu]] (K[sub mu 3][sup 0]) and K[sup ] --> pi[sup 0]e[sup ]nu[sub e] (K[sub e3][sup [plus-minus]]), were used to study the strangeness-changing weak ... [AIP Conf. Proc. 899, 195 (2007)] published Fri Apr 27, 2007.

Inclusive Production of rho [sup [plus-minus] ](770) Meson in Hadronic Decays of Z[sup 0] Boson

A. Beddall, A. Beddall, and A. Bingul
The inclusive production of the charged vector meson rho[sup ](770) in hadronic Z decays is measured with the ALEPH detector at the LEP collider. Decays of rho[sup ] --> pi[sup 0] + pi[sup ] are reconstructed for x > 0.05 where x = E[sub rho]/E[sub beam]. The results are compared with Monte Carlo mo ... [AIP Conf. Proc. 899, 189 (2007)] published Fri Apr 27, 2007.

Advances in Nucleon-Nucleon Scattering Experiments and Their Theoretical Consequences

Sadik Bekteshi, Skender Kabashi, and Burim Kamishi
An overview of critical analysis of the experimental data obtained from nucleon-nucleon scattering is given and investigated in this work. Comparison of the experimental data with results of recent partial wave analysis of Nijmegen group, VPI/GWU and Saclay is given. Potentials of Nijmegen, Bonn and ... [AIP Conf. Proc. 899, 93 (2007)] published Fri Apr 27, 2007.

Neutrino Mixing and the Private Higgs. (arXiv:0807.0612v1 [hep-ph])

ePrint arXiv http://arXiv.org/

A subtraction scheme for computing QCD jet cross sections at NNLO: integrating the subtraction terms I. (arXiv:0807.0509v1 [hep-ph])

ePrint arXiv http://arXiv.org/

$\cos 2 \phi$ asymmetries in unpolarized semi-inclusive DIS. (arXiv:0807.0503v2 [hep-ph])

ePrint arXiv http://arXiv.org/

Loops for Hot QCD. (arXiv:0807.0500v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Effective Theories and Electroweak Precision Constraints. (arXiv:0807.0490v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Partons and jets at strong coupling from AdS/CFT. (arXiv:0807.0489v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Minimal Supersymmetric Left-Right Model. (arXiv:0807.0481v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Chaos, Determinacy and Fractals in Active-Sterile Neutrino Oscillations in the Early Universe. (arXiv:0807.0456v1 [hep-ph])

ePrint arXiv http://arXiv.org/

The Casimir Force in Randall Sundrum Models with q+1 dimensions. (arXiv:0807.0443v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Analytic integration of real-virtual counterterms in NNLO jet cross sections I. (arXiv:0807.0514v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Radiative corrections in K --> 3 pi decays. (arXiv:0807.0515v1 [hep-ph])

ePrint arXiv http://arXiv.org/

Subtraction method of computing QCD jet cross sections at NNLO accuracy. (arXiv:0807.0520v1 [hep-ph])

ePrint arXiv http://arXiv.org/