Astrophysics

Authors and titles for November 2004

[801] arXiv:astro-ph/0411801 [pdf, other]

Title: A Self-Consistent Model for the Formation of Relativistic Outflows in Advection-Dominated Accretion Disks with Shocks

Truong Le, Peter A. Becker

Comments: accepted for publication in Astrophysical Journal Letters

Journal-ref: Astrophys.J. 617 (2004) L25-L28

Subjects: Astrophysics (astro-ph)

[802] arXiv:astro-ph/0411802 [pdf, other]

Title: Nearby early-type galaxies with ionized gas.I. Line-strength indices of the underlying stellar population

R. Rampazzo, F. Annibali, A. Bressan, M. Longhetti, F. Padoan, W.W. Zeilinger

Comments: A&A accepted. Electronic tables will be available at the CDS when the printed version will appear

Subjects: Astrophysics (astro-ph)

[803] arXiv:astro-ph/0411803 [pdf, other]

Title: Dynamical dark energy: Current constraints and forecasts

Amol Upadhye, Mustapha Ishak, Paul J. Steinhardt (Princeton University)

Comments: 24 pages, 20 figures. Added SN systematic uncertainties, extended discussion

Journal-ref: Phys.Rev.D72:063501,2005

Subjects: Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Phenomenology (hep-ph)

[804] arXiv:astro-ph/0411804 [pdf, other]

Title: Continuing a Chandra Survey of Quasar Radio Jets

J. M. Gelbord, H. L. Marshall, D. A. Schwartz, D. M. Worrall, M. Birkinshaw, J. E. J. Lovell, D. L. Jauncey, E. S. Perlman, D. W. Murphy, R. A. Preston

Comments: 4 pages, 8 figures. To appear in `X-Ray and Radio Connections', ed. L.O. Sjouwerman and K.K. Dyer (published electronicly at this http URL). Additional material and higher resolution figures may be found at this http URL

Subjects: Astrophysics (astro-ph)

[805] arXiv:astro-ph/0411805 [pdf, other]

Title: High-Energy Emission From Millisecond Pulsars

Alice K. Harding, Vladimir V. Usov, Alex G. Muslimov

Comments: 34 pages, 6 figures, accepted for publication in Astrophysical Journal

Journal-ref: Astrophys.J. 622 (2005) 531-543

Subjects: Astrophysics (astro-ph)

[806] arXiv:cond-mat/0411342 (cross-list from cond-mat.stat-mech) [pdf, other]

Title: Intensity Thresholds and the Statistics of the Temporal Occurrence of Solar Flares

Marco Baiesi, Maya Paczuski, Attilio L. Stella

Comments: 5 pages, 4 figures, revtex4

Journal-ref: Phys.Rev.Lett. 96 (2006) 051103

Subjects: Statistical Mechanics (cond-mat.stat-mech); Astrophysics (astro-ph)

[807] arXiv:cond-mat/0411408 (cross-list from cond-mat.stat-mech) [pdf, other]

Title: Microcanonical Thermostatistics as Foundation of Thermodynamics. The microscopic origin of condensation and phase separations

D.H.E.Gross

Comments: Invited paper for the conference "Frontiers of Quantum and Mesoscopic Thermodynamics", Prague 26-29 July 2004, 9 pages, 3 figures A detailed discussion of Clausius original papers on entropy are added

Journal-ref: Physica E,2005, special volume dedicated to the proceedings from FQMT04

Subjects: Statistical Mechanics (cond-mat.stat-mech); Astrophysics (astro-ph); Nuclear Theory (nucl-th)

[808] arXiv:cond-mat/0411514 (cross-list from cond-mat.stat-mech) [pdf, other]

Title: Diffusion, Fragmentation and Coagulation Processes: Analytical and Numerical Results

Poul Olesen, Jesper Ferkinghoff-Borg, Mogens H. Jensen, Joachim Mathiesen (Niels Bohr Institute, Copenhagen)

Comments: (28 pages, 6 figures, v2+v3 minor corrections)

Journal-ref: Phys.Rev. E72 (2005) 031103

Subjects: Statistical Mechanics (cond-mat.stat-mech); Astrophysics (astro-ph); Soft Condensed Matter (cond-mat.soft); Chaotic Dynamics (nlin.CD)

[809] arXiv:cond-mat/0411529 (cross-list from cond-mat.stat-mech) [pdf, other]

Title: Regeneration of Stochastic Processes: An Inverse Method

J. Peinke, M. Reza Rahimi Tabar, Muhammad Sahimi, F. Ghasemi

Comments: 5 pages, two columns, 7 figs. to appear, The European Physical Journal B (2006)

Subjects: Statistical Mechanics (cond-mat.stat-mech); Astrophysics (astro-ph); Data Analysis, Statistics and Probability (physics.data-an)

[810] arXiv:gr-qc/0411006 (cross-list from gr-qc) [pdf, other]

Title: Transonic Black Hole Accretion as Analogue System

Tapas Kumar Das

Comments: 20 pages. One figure. To be published in the Proceedings of the Workshop on 'Dynamics and Thermodynamics of Black Holes and Naked Singularities' (Milan, May 2004)

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[811] arXiv:gr-qc/0411012 (cross-list from gr-qc) [pdf, other]

Title: Primordial Density Perturbation in Effective Loop Quantum Cosmology

Golam Mortuza Hossain

Comments: 33 pages, revtex4, few typos and a confusing notation changed; several clarifications, references added, to appear in CQG

Journal-ref: Class.Quant.Grav.22:2511-2532,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[812] arXiv:gr-qc/0411017 (cross-list from gr-qc) [pdf, other]

Title: Probing anisotropies of gravitational-wave backgrounds with a space-based interferometer: geometric properties of antenna patterns and their angular power

Hideaki Kudoh, Atsushi Taruya

Comments: RevTex4, 22 pages, 6 figures (low resolution), typos corrected

Journal-ref: Phys.Rev. D71 (2005) 024025

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[813] arXiv:gr-qc/0411021 (cross-list from gr-qc) [pdf, other]

Title: Coupling of radial and non-radial oscillations of Neutron stars

Andrea Passamonti, Marco Bruni, Leonardo Gualtieri, Carlos F. Sopuerta

Comments: 4 pages. Proceedings of the NATO Advanced Study Institute on the Electromagnetic Spectrum of Neutron Stars, Marmaris, Turkey, June 2004

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[814] arXiv:gr-qc/0411022 (cross-list from gr-qc) [pdf, other]

Title: Newman-Penrose quantities as valuable tools in astrophysical relativity

Marco Bruni, Andrea Nerozzi, Frances White

Comments: 3 pages. Proceedings of 16th SIGRAV conference, Vietri, Italy, September 2004

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[815] arXiv:gr-qc/0411023 (cross-list from gr-qc) [pdf, other]

Title: Self-Interaction and Gauge Invariance

S. Deser

Comments: Missing last reference added. 9 pages, This article, the first paper in Gen. Rel. Grav. [1 (1970) 9], is now somewhat inaccessible; the present posting is the original version, with a few subsequent references included. Updates updated

Journal-ref: Gen.Rel.Grav.1:9-18,1970

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[816] arXiv:gr-qc/0411024 (cross-list from gr-qc) [pdf, other]

Title: On the reliability of the so far performed tests for measuring the Lense-Thirring effect with the LAGEOS satellites

Lorenzo Iorio

Comments: LaTex2e, 22 pages, 1 figure, 1 table, 60 references. Conclusions and Table of Contents added. Estimates of the impact of J6dot on the node-node-perigee combination presented. Typos corrected and minor stylistic changes. Small changes due to G. Melki useful remarks. Lense-Thirring 'memory' effect in EIGEN-GRACE02S discussed

Journal-ref: New Astron. 10 (2005) 603-615

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); Geophysics (physics.geo-ph)

[817] arXiv:gr-qc/0411025 (cross-list from gr-qc) [pdf, other]

Title: Black hole quasinormal modes: hints of quantum gravity?

Emanuele Berti

Comments: 26 pages, 17 figures. To be published in the Proceedings of the Workshop on 'Dynamics and Thermodynamics of Black Holes and Naked Singularities' (Milan, May 2004)

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[818] arXiv:gr-qc/0411033 (cross-list from gr-qc) [pdf, other]

Title: Arbitrary Dimensional Schwarzschild-FRW Black Holes

Chang Jun Gao

Comments: 10 pages

Journal-ref: Class.Quant.Grav. 21 (2004) 4805-4810

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[819] arXiv:gr-qc/0411034 (cross-list from gr-qc) [pdf, other]

Title: Effective refractive index tensor for weak field gravity

Petarpa Boonserm, Celine Cattoen, Tristan Faber, Matt Visser, Silke Weinfurtner (Victoria University, New Zealand)

Comments: V1: 8 pages, no figures, uses this http URL. V2: 13 pages, no figures. Significant additions and clarifications. This version to appear in Classical and Quantum Gravity

Journal-ref: Class.Quant.Grav. 22 (2005) 1905-1916

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[820] arXiv:gr-qc/0411038 (cross-list from gr-qc) [pdf, other]

Title: A Note on the Integral Formulation of Einstein's Equations Induced on a Braneworld

Christine C. Dantas

Comments: 10 pages, no figures, accepted for publication in the General Relativity and Gravitation Journal

Journal-ref: Gen.Rel.Grav. 37 (2005) 959-965

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[821] arXiv:gr-qc/0411040 (cross-list from gr-qc) [pdf, other]

Title: Higher Dimensional Reissner-Nordstr\"om-FRW metric

Chang Jun Gao, Shuang Nan Zhang

Comments: 13 pages

Journal-ref: Gen.Rel.Grav. 38 (2006) 23-32

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[822] arXiv:gr-qc/0411045 (cross-list from gr-qc) [pdf, other]

Title: New Isotropic and Anisotropic Sudden Singularities

John D. Barrow, Christos G. Tsagas (DAMTP)

Comments: Typos corrected. Published version

Journal-ref: Class.Quant.Grav. 22 (2005) 1563-1571

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[823] arXiv:gr-qc/0411048 (cross-list from gr-qc) [pdf, other]

Title: A note on the resonant frequencies of rapidly rotating black holes

Vitor Cardoso

Comments: 5 pages, ReVTeX 4

Journal-ref: Phys.Rev. D70 (2004) 127502

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[824] arXiv:gr-qc/0411056 (cross-list from gr-qc) [pdf, other]

Title: On the Tensor/Scalar Ratio in Inflation with UV Cutoff

A. Ashoorioon, R.B. Mann

Comments: 19 pages, 14 figures, to appear in Nucl. Phys. B; v4: typos corrected, matched with the published version

Journal-ref: Nucl.Phys. B716 (2005) 261-279

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[825] arXiv:gr-qc/0411060 (cross-list from gr-qc) [pdf, other]

Title: The river model of black holes

Andrew J. S. Hamilton, Jason P. Lisle (JILA, U. Colorado)

Comments: 16 pages, 4 figures. The introduction now refers to the paper of Unruh (1981) and the extensive work on analog black holes that it spawned. Thanks to many readers for feedback that called attention to our omissions. Submitted to the American Journal of Physics

Journal-ref: Am.J.Phys.76:519-532,2008

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[826] arXiv:gr-qc/0411061 (cross-list from gr-qc) [pdf, other]

Title: Inside charged black holes I. Baryons

Andrew J. S. Hamilton, Scott E. Pollack (JILA, U. Colorado)

Comments: 31 pages, 12 figures. Minor revisions to agree with version accepted for publication in PRD

Journal-ref: Phys.Rev.D71:084031,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[827] arXiv:gr-qc/0411062 (cross-list from gr-qc) [pdf, other]

Title: Inside charged black holes II. Baryons plus dark matter

Andrew J. S. Hamilton, Scott E. Pollack (JILA, U. Colorado)

Comments: 18 pages, 5 figures. Minor revisions to agree with version accepted for publication in PRD

Journal-ref: Phys.Rev.D71:084032,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[828] arXiv:gr-qc/0411066 (cross-list from gr-qc) [pdf, other]

Title: 5-dimensional Brans-Dicke Theory and Cosmic Acceleration

Li-e Qiang, Yongge Ma, Muxin Han, Dan Yu

Comments: 13 pages, 4 figures, revised version to appear in PRD

Journal-ref: Phys.Rev. D71 (2005) 061501

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[829] arXiv:gr-qc/0411067 (cross-list from gr-qc) [pdf, other]

Title: Dark Energy in the Universe, the Irreversibility of Time and Neutrinos

N. E. Mavromatos (King's College London)

Comments: 13 pages revtex, four figures incorporated; better fit to guarantee positivity on some data; no effects on conclusions, plenary talk at DICE2004 international conference, Piombino (Italy), September 1-4 2004

Journal-ref: Braz.J.Phys. 35 (2005) 284-295

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

[830] arXiv:gr-qc/0411070 (cross-list from gr-qc) [pdf, other]

Title: Structure and stability of the Lukash plane-wave spacetime

John D. Barrow, Christos G. Tsagas (DAMTP)

Comments: Revised version, references added. To appear in Class. Quantum Grav

Journal-ref: Class.Quant.Grav. 22 (2005) 825-840

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[831] arXiv:gr-qc/0411074 (cross-list from gr-qc) [pdf, other]

Title: A scalar field governed cosmological model from noncompact Kaluza-Klein theory

Jose Edgar Madriz Aguilar (IFM, Michoacana University), Mauricio Bellini (Mar del Plata University & CONICET), Francisco Astorga Saenz (IFM, Michoacana University)

Comments: 23 pages, 2 figures. Invited paper for the book: Progress in General Relativity and Quantum Cosmology Research (Nova Science, NY, 2004)

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

[832] arXiv:gr-qc/0411084 (cross-list from gr-qc) [pdf, other]

Title: Some comments on the recent results about the measurement of the Lense-Thirring effect in the gravitational field of the Earth with the LAGEOS and LAGEOS II satellites

Lorenzo Iorio

Comments: Latex2e, 2 tables, 1 figure, 22 pages, 51 references. It refers to the recent paper: I. Ciufolini, Frame Dragging and Lense-Thirring Effect, Gen. this http URL., 36(10), 2257-2270, 2004. Rewritten version. Quantitative estimates of the impact of the secular variations of the even zonals

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); Space Physics (physics.space-ph)

[833] arXiv:gr-qc/0411088 (cross-list from gr-qc) [pdf, other]

Title: Tachyon driven solution to Cosmic Coincidence Problrm

S.K.Srivastaca

Comments: 19 pages

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[834] arXiv:gr-qc/0411100 (cross-list from gr-qc) [pdf, other]

Title: Quantum Effect and Curvature Strength of Naked Singularities

Umpei Miyamoto, Hideki Maeda, Tomohiro Harada

Comments: 21 pages, 1 table, 3 figures. Final version to appear in Progress of Theoretical Physics

Journal-ref: Prog.Theor.Phys.113:513-533,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th); Quantum Physics (quant-ph)

[835] arXiv:gr-qc/0411104 (cross-list from gr-qc) [pdf, other]

Title: Modelling the rotational curves of spiral galaxies with a scalar field

J.P. Mbelek

Comments: Latex, 5 pages with 3 Postscript figures

Journal-ref: Astron.Astrophys.424:761-764,2004

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[836] arXiv:gr-qc/0411118 (cross-list from gr-qc) [pdf, other]

Title: No news for Kerr-Schild fields

Boyko V. Ivanov

Comments: 4 pages, Revtex4

Journal-ref: Phys.Rev. D71 (2005) 044012

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[837] arXiv:gr-qc/0411123 (cross-list from gr-qc) [pdf, other]

Title: Bounding the mass of the graviton using eccentric binaries

D I Jones

Comments: 4 figures, 2 tables. To appear in Astrophysical Journal Letters

Journal-ref: Astrophys.J.618:L115-L118,2004

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[838] arXiv:gr-qc/0411124 (cross-list from gr-qc) [pdf, other]

Title: Early Universe Dynamics in Semi-Classical Loop Quantum Cosmology

James E. Lidsey

Comments: 14 pages, In Press, JCAP

Journal-ref: JCAP 0412 (2004) 007

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[839] arXiv:gr-qc/0411126 (cross-list from gr-qc) [pdf, other]

Title: Formation of voids in the Universe within the Lemaitre-Tolman model

Krzysztof Bolejko, Andrzej Krasinski, Charles Hellaby

Comments: MN2e LaTeX style file, 17 pages, 16 figures, 22 figure files; replecement has minor changes in references

Journal-ref: Mon.Not.Roy.Astron.Soc.362:213-228,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[840] arXiv:gr-qc/0411127 (cross-list from gr-qc) [pdf, other]

Title: Last orbits of binary strange quark stars

Francois Limousin (LUTH), Dorota Gondek-Rosinska (LUTH, CAMK), Eric Gourgoulhon (LUTH)

Comments: 11 pages, 10 figures, improved conclusion and figures, references added, accepted for publication in Phys. Rev. D

Journal-ref: Phys.Rev.D71:064012,2005

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[841] arXiv:gr-qc/0411128 (cross-list from gr-qc) [pdf, other]

Title: Gravitational wave interactions with magnetized plasmas

Joachim Moortgat, Jan Kuijpers

Comments: 4 pages. Proceedings of the NATO Advanced Study Institute on the Electromagnetic Spectrum of Neutron Stars, Marmaris, Turkey, June 2004

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph)

[842] arXiv:gr-qc/0411129 (cross-list from gr-qc) [pdf, other]

Title: Estimating spinning binary parameters and testing alternative theories of gravity with LISA

Emanuele Berti, Alessandra Buonanno, Clifford M. Will

Comments: 29 pages, 9 figures. Matches version accepted in Physical Review D. More stringent checks in the inversion of the Fisher matrix

Journal-ref: Phys.Rev. D71 (2005) 084025

Subjects: General Relativity and Quantum Cosmology (gr-qc); Astrophysics (astro-ph); High Energy Physics - Theory (hep-th)

[843] arXiv:hep-ex/0411033 (cross-list from hep-ex) [pdf, other]

Title: First results from the CERN Axion Solar Telescope (CAST)

CAST Collaboration

Comments: 4 pages, accepted by PRL. Final version after the referees comments

Journal-ref: Phys.Rev.Lett.94:121301,2005

Subjects: High Energy Physics - Experiment (hep-ex); Astrophysics (astro-ph)

[844] arXiv:hep-lat/0411009 (cross-list from hep-lat) [pdf, other]

Title: An Experimenter's View of Lattice QCD

I. Shipsey

Comments: Invited talk delivered at Lattice2004(plenary), Fermilab, June 21-26, 2004. 10 pages

Subjects: High Energy Physics - Lattice (hep-lat); Astrophysics (astro-ph); High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph); High Energy Physics - Theory (hep-th)

[845] arXiv:hep-ph/0411004 (cross-list from hep-ph) [pdf, other]

Title: Massless Gauge Bosons other than the Photon

Bogdan A. Dobrescu

Comments: 5 pages

Journal-ref: Phys.Rev.Lett.94:151802,2005

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph)

[846] arXiv:hep-ph/0411024 (cross-list from hep-ph) [pdf, other]

Title: Scale of Mass Generation for Majorana Neutrinos

Duane A. Dicus, Hong-Jian He

Comments: Presented at the Conference of the Division of Particles and Fields, American Physical Society (DPF-2004), held at University of California, Riverside, CA, USA, August 26-31, 2004

Journal-ref: Int.J.Mod.Phys. A20 (2005) 3082-3088

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph); High Energy Physics - Experiment (hep-ex)

[847] arXiv:hep-ph/0411053 (cross-list from hep-ph) [pdf, other]

Title: Kaluza-Klein Dark Matter, Electrons and Gamma Ray Telescopes

Edward A. Baltz, Dan Hooper

Comments: 10 pages, 2 figures

Journal-ref: JCAP 0507:001,2005

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph)

[848] arXiv:hep-ph/0411089 (cross-list from hep-ph) [pdf, other]

Title: The Classical Stability Of The Ghost Condensate

Alexey Anisimov, Alexander Vikman

Comments: 16 pages, 7 figures Added references, one figure and additional discussion

Journal-ref: JCAP 0504 (2005) 009

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph)

[849] arXiv:hep-ph/0411093 (cross-list from hep-ph) [pdf, other]

Title: May Heavy neutrinos solve underground and cosmic ray puzzles?

K. Belotsky, D. Fargion, M. Khlopov, R.V. Konoplich

Comments: 16 pages, 8 figures

Journal-ref: Phys.Atom.Nucl.71:147-161,2008

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph)

[850] arXiv:hep-ph/0411119 (cross-list from hep-ph) [pdf, other]

Title: Low scale inflation and the curvaton mechanism

Konstantinos Dimopoulos (1), David H. Lyth (1), Yeinzon Rodriguez (1 and 2) ((1) Department of Physics Lancaster University, (2) Centro de Investigaciones Universidad Antonio Narino)

Comments: Latex file in Revtex style. 17 pages, 3 figures. v2: added material and corrected mistakes to take into account the constraints on the behaviour of the radial field coming from the requirements of the spectral index of density perturbations. v3: typos corrected. Reference added. Version accepted for publication in Journal of High Energy Physics

Journal-ref: JHEP0502:055,2005

Subjects: High Energy Physics - Phenomenology (hep-ph); Astrophysics (astro-ph)