| Records |
| Author |
Pandolfi, S.; Giusarma, E.; Kolb, E.W.; Lattanzi, M.; Melchiorri, A.; Mena, O.; Pena, M.; Cooray, A.; Serra, P. |
| Title |
Impact of general reionization scenarios on extraction of inflationary parameters |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
82 |
Issue |
12 |
Pages |
123527 - 10pp |
| Keywords |
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| Abstract |
Determination of whether the Harrison-Zel'dovich spectrum for primordial scalar perturbations is consistent with observations is sensitive to assumptions about the reionization scenario. In light of this result, we revisit constraints on inflationary models using more general reionization scenarios. While the bounds on the tensor-to-scalar ratio are largely unmodified, when different reionization schemes are addressed, hybrid models are back into the inflationary game. In the general reionization picture, we reconstruct both the shape and amplitude of the inflaton potential. We discuss how relaxing the simple reionization restriction affects the reconstruction of the potential through the changes in the constraints on the spectral index, the tensor-to-scalar ratio and the running of the spectral index. We also find that the inclusion of other Cosmic Microwave Background data in addition to the Wilkinson Microwave Anisotropy probe data excludes the very flat potentials typical of models in which the inflationary evolution reaches a late-time attractor, as a consequence of the fact that the running of the spectral index is constrained to be different from zero at 99% confidence level. |
| Address |
[Pandolfi, Stefania; Lattanzi, Massimiliano; Melchiorri, Alessandro] Univ Roma La Sapienza, Dept Phys, I-00185 Rome, Italy |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
ISI:000286744800007 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
530 |
| Permanent link to this record |
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| Author |
Lopez Honorez, L.; Mena, O.; Panotopoulos, G. |
| Title |
Higher-order coupled quintessence |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
82 |
Issue |
12 |
Pages |
123525 - 7pp |
| Keywords |
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| Abstract |
We study a coupled quintessence model in which the interaction with the dark-matter sector is a function of the quintessence potential. Such a coupling can arise from a field dependent mass term for the dark-matter field. The dynamical analysis of a standard quintessence potential coupled with the interaction explored here shows that the system possesses a late-time accelerated attractor. In light of these results, we perform a fit to the most recent Supernovae Ia, Cosmic Microwave Background, and Baryon Acoustic Oscillation data sets. Constraints arising from weak equivalence principle violation arguments are also discussed. |
| Address |
[Lopez Honorez, Laura] UAM, Dept Phys, Madrid 28049, Spain |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
ISI:000286744800005 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
529 |
| Permanent link to this record |
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| Author |
Bodenstein, S.; Bordes, J.; Dominguez, C.A.; Peñarrocha, J.; Schilcher, K. |
| Title |
Charm-quark mass from weighted finite energy QCD sum rules |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
82 |
Issue |
11 |
Pages |
114013 - 5pp |
| Keywords |
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| Abstract |
The running charm-quark mass in the scheme is determined from weighted finite energy QCD sum rules involving the vector current correlator. Only the short distance expansion of this correlator is used, together with integration kernels (weights) involving positive powers of s, the squared energy. The optimal kernels are found to be a simple pinched kernel and polynomials of the Legendre type. The former kernel reduces potential duality violations near the real axis in the complex s plane, and the latter allows us to extend the analysis to energy regions beyond the end point of the data. These kernels, together with the high energy expansion of the correlator, weigh the experimental and theoretical information differently from e. g. inverse moments finite energy sum rules. Current, state of the art results for the vector correlator up to four-loop order in perturbative QCD are used in the finite energy sum rules, together with the latest experimental data. The integration in the complex s plane is performed using three different methods: fixed order perturbation theory, contour improved perturbation theory, and a fixed renormalization scale mu. The final result is (m) over bar (c)(3 GeV) = 1008 +/- 26 MeV, in a wide region of stability against changes in the integration radius s(0) in the complex s plane. |
| Address |
[Bodenstein, S.; Dominguez, C. A.] Univ Cape Town, Ctr Theoret & Math Phys, ZA-7700 Rondebosch, South Africa |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1550-7998 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
ISI:000286567000004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
527 |
| Permanent link to this record |
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| Author |
CDF Collaboration (Aaltonen, T. et al); Cabrera, S. |
| Title |
Improved Search for a Higgs Boson Produced in Association with Z -> l(+)l(-) in p(p)over-bar Collisions at root s=1.96 TeV |
Type |
Journal Article |
| Year |
2010 |
Publication |
Physical Review Letters |
Abbreviated Journal |
Phys. Rev. Lett. |
| Volume |
105 |
Issue |
25 |
Pages |
251802 - 7pp |
| Keywords |
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| Abstract |
We search for the standard model Higgs boson produced with a Z boson in 4: 1 fb(-1) of integrated luminosity collected with the CDF II detector at the Tevatron. In events consistent with the decay of the Higgs boson to a bottom-quark pair and the Z boson to electrons or muons, we set 95% credibility level upper limits on the ZH production cross section multiplied by the H -> b (b) over bar branching ratio. Improved analysis methods enhance signal sensitivity by 20% relative to previous searches. At a Higgs boson mass of 115 GeV/c(2) we set a limit of 5.9 times the standard model cross section. |
| Address |
[Aaltonen, T.; Brucken, E.; Devoto, F.; Mehtala, P.; Orava, R.] Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0031-9007 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
ISI:000286750400004 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
513 |
| Permanent link to this record |
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| Author |
Fernandes, L.M.P.; Freitas, E.D.C.; Ball, M.; Gomez-Cadenas, J.J.; Monteiro, C.M.B.; Yahlali, N.; Nygren, D.; dos Santos, J.M.F. |
| Title |
Primary and secondary scintillation measurements in a Xenon Gas Proportional Scintillation Counter |
Type |
Journal Article |
| Year |
2010 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
5 |
Issue |
|
Pages |
P09006 - 15pp |
| Keywords |
Interaction of radiation with matter; Gaseous detectors; Photon detectors for UV, visible and IR photons (vacuum) (photomultipliers, HPDs, others) |
| Abstract |
NEXT is a new experiment to search for neutrinoless double beta decay using a 100 kg radio-pure high-pressure gaseous xenon TPC. The detector requires excellent energy resolution, which can be achieved in a Xe TPC with electroluminescence readout. Hamamatsu R8520-06SEL photomultipliers are good candidates for the scintillation readout. The performance of this photomultiplier, used as VUV photosensor in a gas proportional scintillation counter, was investigated. Initial results for the detection of primary and secondary scintillation produced as a result of the interaction of 5.9 keV X-rays in gaseous xenon, at room temperature and at pressures up to 3 bar, are presented. An energy resolution of 8.0% was obtained for secondary scintillation produced by 5.9 keV X-rays. No significant variation of the primary scintillation was observed for different pressures (1, 2 and 3 bar) and for electric fields up to 0.8 V cm(-1) torr(-1) in the drift region, demonstrating negligible recombination luminescence. A primary scintillation yield of 81 +/- 7 photons was obtained for 5.9 keV X-rays, corresponding to a mean energy of 72 +/- 6 eV to produce a primary scintillation photon in xenon. |
| Address |
[Fernandes, L. M. P.; Freitas, E. D. C.; Monteiro, C. M. B.; dos Santos, J. M. F.] Univ Coimbra, Dept Phys, Instrumentat Ctr, P-3004516 Coimbra, Portugal, Email: pancho@gian.fis.uc.pt |
| Corporate Author |
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Thesis |
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| Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1748-0221 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
ISI:000283796100003 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
255 |
| Permanent link to this record |
