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Author Agullo, I.; Navarro-Salas, J.; Olmo, G.J.; Parker, L.
Title Revising the observable consequences of slow-roll inflation Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 81 Issue 4 Pages 043514 - 14pp
Keywords
Abstract We study the generation of primordial perturbations in a (single-field) slow-roll inflationary Universe. In momentum space, these (Gaussian) perturbations are characterized by a zero mean and a nonzero variance Delta(2) (k, t). However, in position space the variance diverges in the ultraviolet. The requirement of a finite variance in position space forces one to regularize Delta(2) (k, t). This can (and should) be achieved by proper renormalization in an expanding Universe in a unique way. This affects the predicted scalar and tensorial power spectra (evaluated when the modes acquire classical properties) for wavelengths that today are at observable scales. As a consequence, the imprint of slow-roll inflation on the cosmic microwave background anisotropies is significantly altered. We find a nontrivial change in the consistency condition that relates the tensor-to-scalar ratio r to the spectral indices. For instance, an exact scale-invariant tensorial power spectrum, n(t) = 0, is now compatible with a nonzero ratio r approximate to 0.12 +/- 0.06, which is forbidden by the standard prediction (r = -8n(t)). The influence of relic gravitational waves on the cosmic microwave background may soon come within the range of planned measurements, offering a nontrivial test of the new predictions.
Address [Agullo, Ivan; Olmo, Gonzalo J.; Parker, Leonard] Univ Wisconsin, Dept Phys, Milwaukee, WI 53201 USA, Email: ivan.agullo@uv.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000275898500028 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 479
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Author Olmo, G.J.; Sanchis-Alepuz, H.
Title Hamiltonian formulation of Palatini f(R) theories a la Brans-Dicke theory Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 10 Pages 104036 - 11pp
Keywords
Abstract We study the Hamiltonian formulation of f(R) theories of gravity both in metric and in Palatini formalism using their classical equivalence with Brans-Dicke theories with a nontrivial potential. The Palatini case, which corresponds to the omega = -3/2 Brans-Dicke theory, requires special attention because of new constraints associated with the scalar field, which is nondynamical. We derive, compare, and discuss the constraints and evolution equations for the omega = -3/2 and omega not equal -3/2 cases. Based on the properties of the constraint and evolution equations, we find that, contrary to certain claims in the literature, the Cauchy problem for the omega = -3/2 case is well formulated and there is no reason to believe that it is not well posed in general.
Address [Olmo, Gonzalo J.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: gonzalo.olmo@uv.es
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000290761400007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 631
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Author BABAR Collaboration (del Amo Sanchez, P. et al); Lopez-March, N.; Martinez-Vidal, F.; Oyanguren, A.
Title Searches for the baryon- and lepton-number violating decays B0 -> Lambda_c+ l-, B- --> Lambda l-, and B- --> (Lambda)bar l- Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 9 Pages 091101 - 8pp
Keywords
Abstract Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either Lambda(c) or Lambda and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2-520) x 10(-8) are set on the branching fractions at the 90% confidence level.
Address [Sanchez, P. del Amo; Lees, J. P.; Poireau, V.; Prencipe, E.; Tisserand, V.] Univ Savoie, LAPP, CNRS, IN2P3, F-74941 Annecy Le Vieux, France
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000290718800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 632
Permanent link to this record
 

 
Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the WW plus WZ production cross section using a matrix element technique in lepton plus jets events Type Journal Article
Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 82 Issue 11 Pages 112001 - 15pp
Keywords
Abstract We present a measurement of the WW + WZ production cross section observed in a final state consisting of an identified electron or muon, two jets, and missing transverse energy. The measurement is carried out in a data sample corresponding to up to 4.6 fb(-1) of integrated luminosity at root s = 1.96 TeV collected by the CDF II detector. Matrix element calculations are used to separate the diboson signal from the large backgrounds. The WW + WZ cross section is measured to be 17.4 +/- 3.3 pb in agreement with standard model predictions. A fit to the dijet invariant mass spectrum yields a compatible cross section measurement.
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 Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000286565600004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 514
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Author CDF Collaboration (Aaltonen, T. et al); Cabrera, S.
Title Measurement of the B- lifetime using a simulation free approach for trigger bias correction Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 3 Pages 032008 - 30pp
Keywords
Abstract The collection of a large number of B-hadron decays to hadronic final states at the CDF II Detector is possible due to the presence of a trigger that selects events based on track impact parameters. However, the nature of the selection requirements of the trigger introduces a large bias in the observed proper-decay-time distribution. A lifetime measurement must correct for this bias, and the conventional approach has been to use a Monte Carlo simulation. The leading sources of systematic uncertainty in the conventional approach are due to differences between the data and the Monte Carlo simulation. In this paper, we present an analytic method for bias correction without using simulation, thereby removing any uncertainty due to the differences between data and simulation. This method is presented in the form of a measurement of the lifetime of the B- using the mode B- -> D-0 pi(-). The B- lifetime is measured as tau(-)(B) = 1.663 +/- 0.023 +/- 0.015 ps, where the first uncertainty is statistical and the second systematic. This new method results in a smaller systematic uncertainty in comparison to methods that use simulation to correct for the trigger bias.
Address [Aaltonen, T.; Mehtala, P.; Orava, R.; Osterberg, K.; Saarikko, H.; van Remortel, N.] Univ Helsinki, Dept Phys, Div High Energy Phys, FIN-00014 Helsinki, Finland
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language (down) English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000287393900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 601
Permanent link to this record