- [1] arXiv:0809.0703 [ps, pdf, other]
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Title:NMSSM and Seesaw Physics at LHCComments: 15 pages and 5 figuresSubjects: High Energy Physics - Phenomenology (hep-ph)
We consider extensions of the next-to-minimal supersymmetric model (NMSSM) in which the observed neutrino masses are described in terms of effective dimension six (or seven) rather than dimension five operators. The new particles associated with the double (or triple) seesaw mechanism can have sizable couplings to the known leptons, even with a TeV seesaw scale. In the latter case some of these new short-lived particles could be produced and detected at the LHC.
- [2] arXiv:0809.0705 [pdf, other]
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Title:Implications of the measurements of B_s - B_s bar mixing on SUSY modelsComments: 29 pagesSubjects: High Energy Physics - Phenomenology (hep-ph)
We derive constraints on the mass insertion parameters from the recent measurements of B_s - B_s bar mixing, and discuss their implications on SUSY breaking mediation mechanisms and SUSY flavor models. Some SUSY flavor models are already excluded or disfavored by B_s - B_s bar mixing. We also discuss how to test the SM and SUSY models in the future experiments, by studying other CP violating observables related to b -> s transition, such as the time-dependent CP asymmetry in B -> phi K_S and the direct CP asymmetry in B -> X_s gamma.
- [3] arXiv:0809.0710 [ps, pdf, other]
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Title:Prospects for Yukawa Unified SO(10) SUSY GUTs at the CERN LHCComments: 25 pages including 18 EPS figuresSubjects: High Energy Physics - Phenomenology (hep-ph)
The requirement of t-b-\tau Yukawa coupling unification is common in simple grand unified models based on the gauge group SO(10), and it also places a severe constraint on the expected spectrum of superpartners. For Yukawa-unified models with \mu >0, the spectrum is characterized by three mass scales: {\it i}). first and second generation scalars in the multi-TeV range, {\it ii}). third generation scalars, \mu and m_A in the few-TeV range and {\it iii}). gluinos in the \sim 350-500 GeV range with chargino masses around 100-160 GeV. In such a scenario, gluino pair production should occur at large rates at the CERN LHC, followed by gluino three-body decays into neutralinos or charginos. Discovery of Yukawa-unified SUSY at the LHC should hence be possible with only 1 fb^{-1} of integrated luminosity, by tagging multi-jet events with 2--3 isolated leptons, without relying on missing E_T. A characteristic dilepton mass edge should easily be apparent above Standard Model background. Combining dileptons with b-jets, along with the gluino pair production cross section information, should allow for gluino and neutralino mass reconstruction. A secondary corroborative signal should be visible at higher integrated luminosity in the W1Z2-> 3\ell channel, and should exhibit the same dilepton mass edge as in the gluino cascade decay signal.
- [6] arXiv:0809.0751 [ps, pdf, other]
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Title:$B_d-\bar{B}_d$ mixing vs. $B_s-\bar{B}_s$ mixing with the anomalous $Wtb$ couplingsComments: 5 pages, 2 figuresSubjects: High Energy Physics - Phenomenology (hep-ph)
We explore the effects of the anomalous $tbW$ couplings on the $B_d-\bar{B}_d$ mixing and recently measured $B_s-\bar{B}_s$ mixing. Bounds from the $B \to X_s \gamma$ decays are important for the anomalous top quark couplings and the combined analysis mixings via box diagrams with penguin decays provides strong constraints on the model parameters. We find the bound from the $B_d-\bar{B}_d$ mixing data is stronger than that from the $B_s-\bar{B}_s$ mixing.
- [7] arXiv:0809.0761 [ps, pdf, other]
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Title:Resummation approach in Fractional APT: How many loops do we need to calculate?Authors: Alexander P. BakulevComments: 8 pages, 2 figures, invited talk at the International Workshop "Hadron Structure and QCD" (HSQCD'2008), Gatchina, Russia, June 30 - July 4, 2008Subjects: High Energy Physics - Phenomenology (hep-ph)
We give a short introduction to the Analytic Perturbation Theory (APT) in QCD, discuss its problems and how they can be resolved in Fractional APT (FAPT), and give a brief report about taking into account heavy-quark thresholds in FAPT. Then we describe the resummation approach in the one-loop APT and FAPT, which produces finite answers in both Euclidean and Minkowski regions, provided the generating function P(t) of perturbative coefficients d_n is known. We consider its applications in estimations of the width of Higgs boson decay H^0\to b\bar{b} and of the Adler function D(Q^2) and the ratio R(s) in the N_f=4 region. In order to provide numerical answers we suggest very simple factorially growing models for perturbative coefficients d_n. We see that for the case of Higgs boson decay an accuracy of the order of 1% is reached at N^3LO approximation, when term d_3{\mathcal A}_3 is taken into account. In the case of Adler function D(Q^2) we have an accuracy of the order of 0.1% already at N^2LO (i. e., with taking into account d_2{\mathcal A}_2 term). The main conclusion is: In order to achieve an accuracy of the order of 1%, we do not need to calculate more than four loops and d_4 coefficients are needed only to estimate corresponding generating functions P(t).
- [8] arXiv:0809.0779 [ps, pdf, other]
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Title:The constrained NMSSM: mSUGRA and GMSBAuthors: Ulrich EllwangerComments: 6 pages, 5 Figures. Plenary talk given at SUSY 08Subjects: High Energy Physics - Phenomenology (hep-ph)
We review different constrained versions of the NMSSM: the fully constrained cNMSSM with universal boundary conditions for gauginos and all soft scalar masses and trilinear couplings, and the NMSSM with soft terms from Gauge Mediated Supersymmetry Breaking. Regarding the fully constrained cNMSSM, after imposing LEP constraints and the correct dark matter relic density, one single parameter is sufficient to describe the entire Higgs and sparticle spectrum of the model, which then contains always a singlino LSP. The NMSSM with soft terms from GMSB is phenomenologically viable if (and only if) the singlet is allowed to couple directly to the messenger sector; then various ranges in parameter space satisfy constraints from colliders and precision observables. Motivations for and phenomenological features of extra U(1)' gauge symmetries are briefly reviewed.
- [9] arXiv:0809.0781 [ps, pdf, other]
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Title:Generic Friedberg-Lee Symmetry of Dirac NeutrinosComments: RevTex4 10 pages, 1 figureSubjects: High Energy Physics - Phenomenology (hep-ph)
We write out the generic Dirac neutrino mass operator which possesses the Friedberg-Lee (FL) symmetry and find that its corresponding neutrino mass matrix is asymmetric. Following a simple way to break the FL symmetry, we calculate the neutrino mass eigenvalues and show that the resultant neutrino mixing pattern is nearly tri-bimaximal. Imposing the Hermitian condition on the neutrino mass matrix, we also show that the simplified ansatz is consistent with current experimental data and favors the normal neutrino mass hierarchy.
- [10] arXiv:0809.0785 [ps, pdf, other]
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Title:Solar Neutrinos as Background in Direct Dark Matter SearchesAuthors: J. D. Vergados (Physics Department, University of Ioannina, Ioannina, Greece andTheory Division, CERN 1211, Geneva, CH), I. Giomataris (IRFU, Centre d' etudes de Saclay, Gif sur Yvette CEDEX, France)Comments: 6 pages, 5 figures, Submitted for the DSU proceedings to be published by the American institute of Physics (AIP)Subjects: High Energy Physics - Phenomenology (hep-ph)
The coherent contribution of all neutrons in neutrino nucleus scattering due to the neutral current is examined considering the boron solar neutrinos. These neutrinos could potentially become a source of background in the future dark matter searches aiming at nucleon cross sections in the region well below the few events per ton per year.
- [11] arXiv:0809.0790 [ps, pdf, other]
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Title:QCD corrections to charged triple vector boson production with leptonic decayComments: 16 pages, 9 figures, 3 tablesSubjects: High Energy Physics - Phenomenology (hep-ph)
We compute the O(alpha_s) QCD corrections to charged triple vector boson production at a hadron collider, i.e. the processes pp -> ZZW + X and pp -> WWW + X. Intermediate Higgs boson exchange effects, spin correlations from leptonic vector boson decays, and off-shell contributions are all taken into account. Results are implemented in a fully flexible Monte Carlo program that allows for an easy customization of kinematical cuts and variation of the factorization and renormalization scales. We analyze the dependence of the differential cross sections under scale variations and present distributions where the QCD corrections strongly modify the leading-order results.
- [12] arXiv:0809.0792 [ps, pdf, other]
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Title:Gamma rays and positrons from a decaying hidden gauge bosonSubjects: High Energy Physics - Phenomenology (hep-ph)
We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of hidden gauge boson can explain both the EGRET excess of diffuse gamma rays and the HEAT anomaly in the positron fraction. The spectra of the gamma rays and the positrons have distinctive features; the absence of line emission of the gamma ray and a sharp peak in the positron fraction. Such features may be observed by the GLAST and PAMELA satellites.
- [14] arXiv:0809.0800 [ps, pdf, other]
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Title:Two-loop electroweak next-to-leading logarithms for processes involving heavy quarksComments: 55 pages, LaTeXSubjects: High Energy Physics - Phenomenology (hep-ph)
We derive logarithmically enhanced two-loop virtual electroweak corrections for arbitrary fermion-scattering processes at the TeV scale. This extends results previously obtained for massless-fermion scattering to processes that involve also bottom and top quarks. The contributions resulting from soft, collinear, and ultraviolet singularities in the complete electroweak Standard Model are explicitly extracted from two-loop diagrams to next-to-leading-logarithmic accuracy including all effects associated with symmetry breaking and Yukawa interactions.
- [15] arXiv:0809.0821 [ps, pdf, other]
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Title:Phenomenological aspects of the exotic $T$ quark in 331 modelsComments: 11 pages, 2 figuresSubjects: High Energy Physics - Phenomenology (hep-ph)
In the context of 331 models we analyze the phenomenology of exotic $T$ quarks with electric charge 2/3. We establish bounds for the corresponding masses and mixing angles and study the decay modes $T\to bW$, $tZ$ and $qH$. It is found that the decays into scalars are strongly dependent on the model parameters, and can be the dominant ones in a scenario with approximate flavor symmetry.
- [16] arXiv:0809.0839 [ps, pdf, other]
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Title:Searches for hyperbolic extra dimensions at the LHCAuthors: Tommy OhlssonComments: 3 pages, 4 figures, poster presented at the XXXIVth International Conference on High Energy Physics (ICHEP08), Philadelphia, Pennsylvania, USA, July 30-August 5, 2008Subjects: High Energy Physics - Phenomenology (hep-ph)
In this poster, we present a model of large extra dimensions where the internal space has the geometry of a hyperbolic disc. Compared with the ADD model, this model provides a more satisfactory solution to the hierarchy problem between the electroweak scale and the Planck scale, and it also avoids constraints from astrophysics. Since there is no known analytic form of the Kaluza-Klein spectrum for our choice of geometry, we obtain a spectrum based on a combination of approximations and numerical computations. We study the possible signatures of our model for hadron colliders, especially the LHC, where the most important processes are the production of a graviton together with a hadronic jet or a photon. We find that for the case of hadronic jet production, it is possible to obtain relatively strong signals, while for the case of photon production, this is much more difficult.
- [17] arXiv:0809.0841 [ps, pdf, other]
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Title:Flavor symmetry analysis of charmless B --> VP decaysComments: 21 pages and 2 plotsSubjects: High Energy Physics - Phenomenology (hep-ph)
Based upon flavor SU(3) symmetry, we perform global fits to charmless, B decays into one pseudoscalar meson and one vector meson in the final states. We consider different breaking schemes to test the symmetry assumption, and find that the exact symmetry one renders the best fit. The $(\bar\rho,\bar\eta)$ vertex of the unitarity triangle (UT) constrained by our fits is consistent with other methods within errors. The fit results are used to compute branching ratio and CP asymmetry observables in all of the decay modes, particularly those in the $B_s$ decays to be measured at the Tevatron and LHC experiments.
- [18] arXiv:0809.0842 [pdf, other]
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Title:The Golden Modes B^0 -> J/psi K_{S,L} in the Era of Precision Flavour PhysicsComments: 4+1 pages, 4 figuresSubjects: High Energy Physics - Phenomenology (hep-ph)
The B^0 -> J/\psi K_{S,L} channels are outstanding probes of CP violation. We have a detailed look at the associated Standard-Model uncertainties, which are related to doubly Cabibbo-suppressed penguin contributions, and point out that these usually neglected effects can actually be taken into account unambiguously through the CP asymmetries and the branching ratio of the B^0 -> J/\psi pi^0 decay. Using the most recent B-factory measurements, we find a negative shift of the extracted value of beta, which softens the tension in the fits of the unitarity triangle. In addition, this strategy can be used to constrain a possible new-physics phase in B^0-\bar B^0 mixing. The proposed strategy is crucial to fully exploit the tremendous accuracies for the search for this kind of new physics that can be achieved at the LHC and future super-flavour factories.
- [19] arXiv:0809.0846 [ps, pdf, other]
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Title:Direct photon production at HERA, the Tevatron and the LHCComments: 16 pages, 18 figures, Proceedings of the HERA-LHC workshop (CERN-DESY), 2007-2008Subjects: High Energy Physics - Phenomenology (hep-ph)
We review several most recent prompt-photon measurements at HERA and the Tevatron and discuss their implication for future measurements at the LHC. A comparison to Monte Carlo models, as well as to NLO QCD predictions based on the standard DGLAP and the kT-factorization approaches is discussed. Effects from renormalization and factorization scale uncertainties, as well as uncertainties on the gluon density distribution inside a proton are discussed.
- [21] arXiv:0809.0872 [ps, pdf, other]
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Title:A Method to Measure cos(2beta) Using Time-Dependent Dalitz Plot Analysis of B0 -> D_CP pi+ pi-Comments: 22 pages, 9 figures, 3 tablesSubjects: High Energy Physics - Phenomenology (hep-ph)
We present a feasibility study of a method to measure the cosine of twice the CKM Unitarity Triangle angle beta using a time-dependent Dalitz plot analysis of B0 -> D pi+ pi- decays, where the neutral D meson is reconstructed in decays to CP eigenstates. We show that this method can be used at the B factories to make a measurement of cos(2beta) that is competitive with, or more precise than, other techniques using different quark-level transitions, while sin(2beta) can be measured to an accuracy more precise than any existing measurement using b -> c ubar d transitions. Furthermore, this technique has great potential to be employed at LHCb.
- [25] arXiv:0809.0623 (cross-list from astro-ph) [ps, pdf, other]
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Title:Quantum slow-roll and quantum fast-roll inflationary initial conditions: CMB quadrupole suppression and further effects on the low CMB multipolesComments: LaTeX, 14 pages, 3 figuresSubjects: Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)
Quantum fast-roll initial conditions for the inflaton which are different from the classical fast-roll conditions and from the quantum slow-roll conditions can lead to inflation that last long enough. These quantum fast-roll initial conditions for the inflaton allow for kinetic energies of the same order of the potential energies and nonperturbative inflaton modes with nonzero wavenumbers. Their evolution starts with a transitory epoch where the redshift due to the expansion succeeds to assemble the quantum excited modes of the inflaton in a homogeneous (zero mode) condensate, and the large value of the Hubble parameter succeeds to overdamp the fast-roll of the redshifted inflaton modes. After this transitory stage the effective classical slow-roll epoch is reached. Most of the efolds are produced during the slow-roll epoch and we recover the classical slow-roll results for the scalar and tensor metric perturbations plus corrections. These corrections are important, both for scalar and for tensor perturbations, if scales which are horizon-size today exited the horizon by the end of the transitory stage and as a consequence the lower CMB multipoles get suppressed (fast-roll) or enhanced (precondensate). These two types of corrections can compete and combine in a scale dependent manner. They arise as natural consequences of the quantum nonperturbative inflaton dynamics, and provide a consistent and contrastable model for the origin of the suppression of the quadrupole and for other departures of the low CMB multipoles from the slow-roll inflation-LambdaCMB model which are to be contrasted to the TE and EE multipoles and to the forthcoming and future CMB data.
- [26] arXiv:0809.0639 (cross-list from hep-th) [ps, pdf, other]
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Title:The Flavor Group Delta(6n^2)Comments: 20 pagesSubjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
Many non-Abelian finite subgroups of SU (3) have been used to explain the flavor structure of the Standard Model. In order to systematize and classify successful models, a detailed knowledge of their mathematical structure is necessary. In this paper we shall therefore look closely at the series of finite non-Abelian groups known as Delta(6n^2), its smallest members being S3 (n = 1) and S4 (n = 2). For arbitrary n, we determine the conjugacy classes, the irreducible representations, the Kronecker products as well as the Clebsch-Gordan coefficients.
- [27] arXiv:0809.0840 (cross-list from cs.CE) [ps, pdf, other]
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Title:HEP data analysis using jHepWork and JavaAuthors: S.ChekanovComments: 5 pages, Proceedings of the HERA-LHC workshops (2007-2008), DESY-CERNSubjects: Computational Engineering, Finance, and Science (cs.CE); High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph)
A role of Java in high-energy physics and recent progress in development of a platform-independent data-analysis framework, jHepWork, is discussed. The framework produces professional graphics and has many libraries for data manipulation.
- [28] arXiv:0801.0095 (replaced) [ps, pdf, other]
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Title:Mass matrices for quarks and leptons in triangular formComments: Latex, 20 pages, no figures, extended and modified version to be published in Acta Phys. Pol. BSubjects: High Energy Physics - Phenomenology (hep-ph)
- [30] arXiv:0804.3941 (replaced) [ps, pdf, other]
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Title:RS model with a small curvature and two-photon production at the LHCAuthors: A.V. KisselevComments: 23 pages, 12 figures. Appendix and 4 figures are addedSubjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Experiment (hep-ex)
- [31] arXiv:0805.0710 (replaced) [ps, pdf, other]
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Title:Quantitative study of the transverse correlation of soft gluons in high energy QCDSubjects: High Energy Physics - Phenomenology (hep-ph)
- [32] arXiv:0805.1119 (replaced) [ps, pdf, other]
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Title:Search for a promising tetraquark candidate $X(ud\bar{s}\bar{s})$ in $pn\to \Lambda\Lambda X$Comments: Revtex, 9 pages and 5 eps figures; revised version with additional calculations includedSubjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Experiment (hep-ex)
- [34] arXiv:0805.3000 (replaced) [ps, pdf, other]
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Title:Neutrino Masses, Leptogenesis, and Unification in the Absence of Low Energy SupersymmetryComments: 26 pages, 3 figures, typos corrected and references added, published in JHEPJournal-ref: JHEP09(2008)020Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)
- [35] arXiv:0805.4074 (replaced) [ps, pdf, other]
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Title:Semileptonic decays of $B_{s1}$, $B_{s2}^*$, $B_{s0}$ and $B_{s1}'$Comments: 8 pages, 5 figures, 8 tables. Typos correctedSubjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Experiment (hep-ex)
- [36] arXiv:0805.4542 (replaced) [ps, pdf, other]
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Title:One-Loop Effective Action in Orbifold CompactificationsAuthors: Gero von GersdorffComments: 30 pages, 1 figure, 3 tables, v2: appendix on zeta function regularization added, discussion of 6d example expanded, version to appear in JHEPSubjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
- [37] arXiv:0806.0247 (replaced) [ps, pdf, other]
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Title:The color gauge invariance of QCD at non-zero tadpole termAuthors: V. GogokhiaComments: 13 pages, 1 figure, no tables, English improved, some clarifications introduced as well as substantial new material added, some references removedSubjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
- [38] arXiv:0807.1046 (replaced) [ps, pdf, other]
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Title:Higgs versus Matter in the Heterotic LandscapeComments: 29 pages, 1 figure. Final version to appear in Nucl. Phys. BSubjects: High Energy Physics - Theory (hep-th); High Energy Physics - Phenomenology (hep-ph)
- [39] arXiv:0808.0899 (replaced) [ps, pdf, other]
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Title:Placing direct limits on the mass of earth-bound dark matterAuthors: Stephen L. AdlerComments: Latex, 5 pages; v2 has Added Note, v4 has added references and footnotesSubjects: Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph); Space Physics (physics.space-ph)
- [41] arXiv:0808.3583 (replaced) [ps, pdf, other]
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Title:Testing non-standard CP violation in neutrino propagationAuthors: Walter WinterComments: 6 pages, 4 figures. Some references added and typos correctedSubjects: High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Experiment (hep-ex)
- [42] arXiv:0809.0471 (replaced) [ps, pdf, other]
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Title:M2 signatures in psi(2S) radiative decaysAuthors: Jonathan L. RosnerComments: 8 pages, 4 figures, to be submitted to Phys. Rev. D. Additional data and referenceSubjects: High Energy Physics - Phenomenology (hep-ph)
- [43] arXiv:0809.0549 (replaced) [ps, pdf, other]
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Title:What HERA may provide ?Authors: Hannes Jung, Albert De Roeck, Jochen Bartels, Olaf Behnke, Johannes Blumlein, Stanley Brodsky, Amanda Cooper-Sarkar, Michal Deak, Robin Devenish, Markus Diehl, Thomas Gehrmann, Guenter Grindhammer, Gosta Gustafson, Valery Khoze, Albert Knutsson, Max Klein, Frank Krauss, Krzysztof Kutak, Eric Laenen, Leif Lonnblad, Leszek Motyka, Paul R. Newman, Fred Olness, Daniel Pitzl, Marta Ruspa, Agustin Sabio Vera, Gavin P. Salam, Thomas Schorner-Sadenius, Mark StrikmanComments: resulting from a discussion session at DIS08, 21 pagesSubjects: High Energy Physics - Phenomenology (hep-ph)