1. |
- Andersen, JR, et al.
(author)
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Small-x phenomenology - summary and status 2002
- 2004
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In: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 35:1, s. 67-98
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Research review (peer-reviewed)abstract
- A second workshop on small-x physics, within the Small-x Collaboration, was held in Lund in June 2002 with the aim of over-viewing recent theoretical progress in this area and summarizing the experimental status.
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2. |
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3. |
- Andersson, Bo, et al.
(author)
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Small x phenomenology: summary and status
- 2002
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In: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 25:1, s. 77-101
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Research review (peer-reviewed)abstract
- The aim of this paper is to summarize the general status of our understanding of small-x physics. It is based on presentations and discussions at an informal meeting OIL this topic held in Lund, Sweden, in March 2001. This document also marks the founding of an informal collaboration between experimentalists and theoreticians with a special interest in small-x physics. This paper is dedicated to the memory of Bo Andersson. who died unexpectedly from a heart attack on March 4th, 2002.
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4. |
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5. |
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6. |
- Bertini, Marc, et al.
(author)
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PYTHIA version 7-0.0 - a proof-of-concept version
- 2001
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In: Computer Physics Communications. - 0010-4655. ; 134:3, s. 365-391
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Journal article (peer-reviewed)abstract
- This document describes the first proof-of-concept version of the PYTHIA7 program. PYTHIA7 is a complete re-write of the PYTHIA program in C++. It is mainly intended to be a replacement for the `Lund' family of event generators, but is also a framework with a structure suitable for implementing any event generator model. In this document, the structure of the program is presented both from the user and the developer point of view. It is not intended to be a complete manual, but together with the documentation provided in the distribution, it should be sufficient to start working with the program.
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7. |
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8. |
- Cox, B. E., et al.
(author)
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Hard color singlet exchange at the Tevatron
- 2000
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In: Deep inelastic scattering. Proceedings, 8th International Workshop, DIS 2000, Liverpool, UK, April 25-30, 2000. ; , s. 577-579
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Conference paper (other academic/artistic)
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9. |
- Cox, B. E., et al.
(author)
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What is the experimental evidence for the BFKL pomeron?
- 2000
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In: From e^+ e^- to Heavy Ion Collisions : Proceedings of the 30th International Symposium on Multiparticle Dynamics (ISMD 2000), Tihany, Hungary, October 9-15, 2000 - Proceedings of the 30th International Symposium on Multiparticle Dynamics (ISMD 2000), Tihany, Hungary, October 9-15, 2000. - 9789810246556 ; , s. 86-92
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Conference paper (other academic/artistic)
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10. |
- Giele, Walter, et al.
(author)
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The QCD / SM working group: Summary report
- 2002
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In: Physics at TeV colliders. Proceedings, Euro Summer School, Les Houches, France, May 21-June 1, 2001. ; , s. 275-426, s. 275-426
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Conference paper (other academic/artistic)
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11. |
- Gustafson, Gösta, et al.
(author)
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Gluon distribution functions in the k(perpendicular to) -factorization approach
- 2002
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; 33:10, s. 2989-2993
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Journal article (peer-reviewed)abstract
- At small x, the effects of finite transverse momenta of partons inside a hadron become increasingly important, especially in analyses of jets and heavy-quark production. These effects can be systematically accounted for in a formalism based on k(perpendicular to)-factorization and unintegrated distribution functions. We present results for the unintegrated distribution function, together with the corresponding integrated one, obtained within the framework of the Linked Dipole Chain model. Comparisons are made to results obtained within other approaches.
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12. |
- Gustafson, Gösta, et al.
(author)
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Hadronic collisions in the linked dipole chain model
- 2003
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In: Physical Review D (Particles, Fields, Gravitation and Cosmology). - 1550-2368. ; 67:034020:3
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Journal article (peer-reviewed)abstract
- We apply the Linked Dipole Chain model to hadronic collisions using a modified version of the LDCMC Monte Carlo program. In particular we investigate the effects of multiple scatterings, which in this framework are reformulated in terms of the production of multiple chains of dipoles. We find, among other things, that this way of describing multiple scatterings is less sensitive to the treatment of soft, non-perturbative, scatterings. Although the results presented here are only at parton level, by comparing with corresponding results from PYTHIA, we are confident that our model will be able to describe essential features of high energy hadronic collisions, including underlying events and jet-pedestal effects in high pT events. The model should also be applicable to estimates of transverse energy flow in high energy heavy ion collisions, of interest in analyses of signals for quark-gluon plasma formation.
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13. |
- Jung, Hannes, et al.
(author)
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Monte Carlo generators and the CCFM equation
- 2000
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In: ; , s. 297-300
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Conference paper (peer-reviewed)abstract
- We discuss three implementations of the CCFM evolution equations in event generator programs. We find that some of them are able to describe observables such as forward jet rates in DIS at HERA, but only if the so-called consistency constraint is removed. We also find that these results are sensitive to the treatment of non-singular terms in the gluon splitting function.
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14. |
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15. |
- Jung, H., et al.
(author)
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Some comments on the current status of event generators for small-x
- 2000
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In: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 26:5, s. 707-711
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Journal article (other academic/artistic)abstract
- We discuss some aspects of the current status of event generators for small-x DIS. In particular we report on recent results using the CCFM evolution implemented in the SMALLX and CASCADE program concerning the importance of the so-called consistency constraint, and compare with the linked dipole chain model implemented in the LDC program. We point out some potential problems with the resolved virtual photon approach to small-x final states. We do not, however, discuss the fact that the ARIADNE program, implementing the soft-radiation dipole cascade, reproduces the bulk of small-x final-state data from HERA.
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16. |
- Lipatov, AV, et al.
(author)
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Study of the linked dipole chain model in heavy quark production at the Tevatron
- 2004
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :1
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Journal article (peer-reviewed)abstract
- We present calculations of charm and beauty production at Tevatron within the framework of k(T)-factorization, using the unintegrated gluon distributions as obtained from the Linked Dipole Chain model. The analysis covers transverse momentum and rapidity distributions and the azimuthal correlations between b and (b) over bar quarks (or rather muons from their decay) which are powerful tests for the different unintegrated gluon distributions. We compare the theoretical results with recent experimental data taken by DO and CDF collaborations at the Tevatron Run I and II.
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17. |
- Lönnblad, Leif, et al.
(author)
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Central exclusive scalar luminosities from the linked dipole chain model gluon densities
- 2004
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In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :2
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Journal article (peer-reviewed)abstract
- We investigate the implication of uncertainties in the unintegrated gluon distribution for the predictions for central exclusive production of scalars at hadron colliders. We use parameterizations of the k(perpendicular to)-unintegrated gluon density obtained from the Linked Dipole Chain model, applying different options for the treatment of non-leading terms. We find that the luminosity function for central exclusive production is very sensitive to details of the transverse momentum distribution of the gluon which, contrary to the k(perpendicular to)-integrated distribution, is not very well constrained experimentally.
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18. |
- Lönnblad, Leif
(author)
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Combining matrix elements and the dipole cascade model
- 2002
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In: Acta Physica Polonica B. - 0587-4254. ; 33:10, s. 3171-3176
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Conference paper (peer-reviewed)abstract
- An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the ARIADNE program is corrected to match the fixed order tree-level matrix elements for e(+)e(-) --> n jets. For the results presented here, matrix elements were used up to second order in alpha(S) but the scheme is applicable also for higher orders.
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19. |
- Lönnblad, Leif
(author)
-
Correcting the colour-dipole cascade model with fixed order matrix elements
- 2002
-
In: Journal of High Energy Physics. - : Springer Science and Business Media LLC. - 1029-8479. ; :5
-
Journal article (peer-reviewed)abstract
- An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the Ariadne program is corrected to match the fixed order tree-level matrix elements for e e(+) --> n jets. The result is a full parton level generator for e e(+) annihilation where the generated states are correct on tree-level to fixed order in alpha(s) and to all orders with modified leading logarithmic (MLLA) accuracy. In this paper, matrix elements are used up to second order in alpha(s), but the scheme is applicable also for higher orders. A strategy for also including exact virtual corrections to fixed order is suggested and the possibility to extend the scheme to hadronic collisions is discussed.
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20. |
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21. |
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22. |
- Lönnblad, Leif
(author)
-
Modeling diffractive final states
- 2002
-
In: Acta Physica Polonica B. - 0587-4254. ; 33:10, s. 3231-3236
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Conference paper (peer-reviewed)abstract
- I will discuss some aspects of modeling diffractive final states with event generators. In the first part of the talk I will discuss multiple scatterings in hard diffraction in hadron collisions and its effects on gap survival and hadronization corrections. In the second part I will argue that the study of the 'pomeron remnant' in hard diffraction at HERA may be the best way of distinguishing resolved pomeron models from dipole models and soft colour interaction models.
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23. |
- Lönnblad, Leif, et al.
(author)
-
Multi-hadron final states
- 2002
-
In: Acta Physica Polonica B. - 0587-4254. ; 33:10, s. 3329-3347
-
Conference paper (other academic/artistic)abstract
- This summary aims to highlight major results and insights gained from recent studies of hadronic final states in ep, p (p) over bar, e(+)e(-), as well as relevant theoretical developments, presented in the Multi-Hadron Final States parallel sessions of the DIS2002 workshop held in Krakow, Poland in May 2002.
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24. |
- Lönnblad, Leif
(author)
-
Status of the PYTHIA7 project
- 2003
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In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 502:2-3, s. 549-551
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Journal article (peer-reviewed)abstract
- I will describe the current status of the PYTHIA7 project to completely rewrite the 'Lund family' of event generators in C++. The PYTHIA7 program is a general platform for implementing event generator models and is not limited to the standard Lund programs (PYTHIA, JETSET, ARIADNE,...). Also the future C++ version of the HERWIG program will be implemented in the PYTHIA7 framework. The underlying framework is now rather stable and the project has gone into a phase where physics models are being implemented. (C) 2003 Elsevier Science B.V. All rights reserved.
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25. |
- Lönnblad, Leif, et al.
(author)
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ThePEG, Pythia7 and Ariadne
- 2004
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In: [Host publication title missing]. - 8088880572 ; II, s. 668-671
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Conference paper (peer-reviewed)
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