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Author Geng, L.S.; Molina, R.; Oset, E.
Title On the chiral covariant approach to rho rho scattering Type Journal Article
Year 2017 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 41 Issue 12 Pages (down) 124101 - 9pp
Keywords rho-rho scattering; unitary chiral approaches; on-shell approximations
Abstract We examine in detail a recent work (D. Gulmez, U. G. Meibner and J. A. Oller, Eur. Phys. J. C, 77: 460 (2017)), where improvements to make rho rho scattering relativistically covariant are made. The paper has the remarkable conclusion that the J=2 state disappears with a potential which is much more attractive than for J=0, where a bound state is found. We trace this abnormal conclusion to the fact that an “on-shell” factorization of the potential is done in a region where this potential is singular and develops a large discontinuous and unphysical imaginary part. A method is developed, evaluating the loops with full rho propagators, and we show that they do not develop singularities and do not have an imaginary part below threshold. With this result for the loops we define an effective potential, which when used with the Bethe-Salpeter equation provides a state with J=2 around the energy of the f(2)(1270). In addition, the coupling of the state to is evaluated and we find that this coupling and the T matrix around the energy of the bound state are remarkably similar to those obtained with a drastic approximation used previously, in which the q(2) terms of the propagators of the exchanged rho mesons are dropped, once the cut-off in the rho rho loop function is tuned to reproduce the bound state at the same energy.
Address [Geng, Li-Sheng] Beihang Univ, Sch Phys & Nucl Energy Engn, Beijing 100191, Peoples R China, Email: lisheng.geng@buaa.edu.cn
Corporate Author Thesis
Publisher Chinese Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000417112000005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3398
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Author Bombacigno, F.; Boudet, S.; Olmo, G.J.; Montani, G.
Title Big bounce and future time singularity resolution in Bianchi I cosmologies: The projective invariant Nieh-Yan case Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 12 Pages (down) 124031
Keywords
Abstract We extend the notion of the Nieh-Yan invariant to generic metric-affine geometries, where both torsion and nonmetricity are taken into account. Notably, we show that the properties of projective invariance and topologicity can be independently accommodated by a suitable choice of the parameters featuring this new Nieh-Yan term. We then consider a special class of modified theories of gravity able to promote the Immirzi parameter to a dynamical scalar field coupled to the Nieh-Yan form, and we discuss in more detail the dynamics of the effective scalar tensor theory stemming from such a revised theoretical framework. We focus, in particular, on cosmological Bianchi I models and we derive classical solutions where the initial singularity is safely removed in favor of a big bounce, which is ultimately driven by the nonminimal coupling with the Immirzi field. These solutions, moreover, turn out to be characterized by finite time singularities, but we show that such critical points do not spoil the geodesic completeness and wave regularity of these spacetimes.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000661819200005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4870
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Author Rosa, J.L.; Lobo, F.S.N.; Olmo, G.J.
Title Weak-field regime of the generalized hybrid metric-Palatini gravity Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 104 Issue 12 Pages (down) 124030 - 11pp
Keywords
Abstract In this work we explore the dynamics of the generalized hybrid metric-Palatini theory of gravity in the weak-field, slow-motion regime. We start by introducing the equivalent scalar-tensor representation of the theory, which contains two scalar degrees of freedom, and perform a conformal transformation to the Einstein frame. Linear perturbations of the metric in a Minkowskian background are then studied for the metric and both scalar fields. The effective Newton constant and the PPN parameter. of the theory are extracted after transforming back to the (original) Jordan frame. Two particular cases where the general method ceases to be applicable are approached separately. A comparison of these results with observational constraints is then used to impose bounds on the masses and coupling constants of the scalar fields.
Address [Rosa, Joao Luis] Univ Tartu, Inst Phys, W Ostwaldi 1, EE-50411 Tartu, Estonia, Email: joaoluis92@gmail.com;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000762071800011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5142
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Author Dudley, R.A.; Anderson, P.R.; Balbinot, R.; Fabbri, A.
Title Correlation patterns from massive phonons in 1+1 dimensional acoustic black holes: A toy model Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 98 Issue 12 Pages (down) 124011 - 18pp
Keywords
Abstract Transverse excitations in analogue black holes induce a masslike term in the longitudinal mode equation. With a simple toy model we show that correlation functions display a rather rich structure characterized by groups of approximately parallel peaks. For the most part the structure is completely different from that found in the massless case.
Address [Dudley, Richard A.; Anderson, Paul R.] Wake Forest Univ, Dept Phys, Winston Salem, NC 27109 USA, Email: dudlra13@wfu.edu;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000452979300003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3834
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Author Gariazzo, S.; Mena, O.; Miralles, V.; Ramirez, H.; Boubekeur, L.
Title Running of featureful primordial power spectra Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 95 Issue 12 Pages (down) 123534 - 7pp
Keywords
Abstract Current measurements of the temperature and polarization anisotropy power spectra of the cosmic microwave background (CMB) seem to indicate that the naive expectation for the slow-roll hierarchy within the most simple inflationary paradigm may not be respected in nature. We show that a primordial power spectrum with localized features could in principle give rise to the observed slow-roll anarchy when fitted to a featureless power spectrum. From a model comparison perspective, and assuming that nature has chosen a featureless primordial power spectrum, we find that, while with mock Planck data there is only weak evidence against a model with localized features, upcoming CMB missions may provide compelling evidence against such a nonstandard primordial power spectrum. This evidence could be reinforced if a featureless primordial power spectrum is independently confirmed from bispectrum and/or galaxy clustering measurements.
Address [Gariazzo, Stefano; Mena, Olga; Miralles, Victor; Ramirez, Hector] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000404475200004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3186
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Author Middeldorf-Wygas, M.M.; Oldengott, I.M.; Bödeker, D.; Schwarz, D.J.
Title Cosmic QCD transition for large lepton flavor asymmetries Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 105 Issue Pages (down) 123533 - 10pp
Keywords
Abstract We study the impact of large lepton flavor asymmetries on the cosmic QCD transition. Scenarios of unequal lepton flavor asymmetries are observationally almost unconstrained and therefore open up a whole new parameter space for the cosmic QCD transition. We find that for large asymmetries, the formation of a Bose-Einstein condensate of pions can occur and identify the corresponding parameter space. In the vicinity of the QCD transition scale, we express the pressure in terms of a Taylor expansion with respect to the complete set of chemical potentials. The Taylor coefficients rely on input from lattice QCD calculations from the literature. The domain of applicability of this method is discussed.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5497
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Author Alicki, R.; Barenboim, G.; Jenkins, A.
Title Quantum thermodynamics of de Sitter space Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 12 Pages (down) 123530 - 13pp
Keywords
Abstract We consider the local physics of an open quantum system embedded in an expanding three-dimensional space x, evolving in cosmological time t, weakly coupled to a massless quantum field. We derive the corresponding Markovian master equation for the system's nonunitary evolution and show that, for a de Sitter space with Hubble parameter h 1/4 const, the background fields act as a physical heat bath with temperature TdS 1/4 h/2z. The energy density of this bath obeys the Stefan-Boltzmann law pdS proportional to h4. We comment on how these results clarify the thermodynamics of de Sitter space and support previous arguments for its instability in the infrared. The cosmological implications are considered in an accompanying Letter.
Address [Alicki, Robert; Jenkins, Alejandro] Univ Gdansk, Int Ctr Theory Quantum Technol ICTQT, PL-80308 Gdansk, Poland, Email: robert.alicki@ug.edu.pl;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001145885800017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5918
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Author Hagstotz, S.; de Salas, P.F.; Gariazzo, S.; Pastor, S.; Gerbino, M.; Lattanzi, M.; Vagnozzi, S.; Freese, K.
Title Bounds on light sterile neutrino mass and mixing from cosmology and laboratory searches Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 104 Issue 12 Pages (down) 123524 - 20pp
Keywords
Abstract We present a consistent framework to set limits on properties of light sterile neutrinos coupled to all three active neutrinos using a combination of the latest cosmological data and terrestrial measurements from oscillations, beta-decay, and neutrinoless double-beta-decay (0 nu beta beta) experiments. We directly constrain the full 3 + 1 active-sterile mixing matrix elements vertical bar U-alpha 4 vertical bar(2) , with alpha is an element of (e,mu,tau), and the mass-squared splitting Delta m(41)(2) (math) m(4)(2) – m(1)(2). We find that results for a 3 + 1 case differ from previously studied 1 + 1 scenarios where the sterile is coupled to only one of the neutrinos, which is largely explained by parameter space volume effects. Limits on the mass splitting and the mixing matrix elements are currently dominated by the cosmological datasets. The exact results are slightly prior dependent, but we reliably find all matrix elements to be constrained below vertical bar U-alpha 4 vertical bar(2) less than or similar to 10(-3) . Short-baseline neutrino oscillation hints in favor of eV-scale sterile neutrinos arc in serious tension with these bounds, irrespective of prior assumptions. We also translate the bounds from the cosmological analysis into constraints on the parameters probed by laboratory searches, such as m(beta) or m(beta)(beta), the effective mass parameters probed by beta-decay and 0 nu beta beta searches, respectively. When allowing for mixing with a light sterile neutrino, cosmology leads to upper bounds of m(beta) < 0.09 eV and m(beta)(beta )< 0.07 eV at 95% CL, more stringent than the limits from current laboratory experiments.
Address [Hagstotz, Steffen; de Salas, Pablo F.] Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, Roslagstullsbacken 21A, SE-10691 Stockholm, Sweden, Email: steffen.hagstotz@fysik.su.se
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000730829500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5055
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Author Servant, G.; Simakachorn, P.
Title Constraining postinflationary axions with pulsar timing arrays Type Journal Article
Year 2023 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 108 Issue 12 Pages (down) 123516 - 16pp
Keywords
Abstract Models that produce axionlike particles (ALPs) after cosmological inflation due to spontaneous U(1) symmetry breaking also produce cosmic-string networks. Those axionic strings lose energy through gravitational-wave emission during the whole cosmological history, generating a stochastic background of gravitational waves that spans many decades in frequency. We can therefore constrain the axion decay constant and axion mass from limits on the gravitational-wave spectrum and compatibility with dark matter abundance as well as dark radiation. We derive such limits from analyzing the most recent NANOGrav data from pulsar timing arrays (PTAs). The limits are similar to the Neff bounds on dark radiation for ALP masses ma less than or similar to 10-22 eV. On the other hand, for heavy ALPs with ma greater than or similar to 0.1 GeV and NDW not equal 1, new regions of parameter space can be probed by PTA data due to the dominant domain-wall contribution to the gravitational-wave background.
Address [Servant, Geraldine] DESY, Notkestr 85, D-22607 Hamburg, Germany, Email: geraldine.servant@desy.de;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:001155748800012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5933
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Author Nunes, R.C.; Vagnozzi, S.; Kumar, S.; Di Valentino, E.; Mena, O.
Title New tests of dark sector interactions from the full-shape galaxy power spectrum Type Journal Article
Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 105 Issue 12 Pages (down) 123506 - 18pp
Keywords
Abstract We explore the role of redshift-space galaxy clustering data in constraining nongravitational interactions between dark energy (DE) and dark matter (DM), for which state-of-the-art limits have so far been obtained from late-time background measurements. We use the joint likelihood for prereconstruction full-shape (FS) galaxy power spectrum and postreconstruction Baryon Acoustic Oscillation (BAO) measurements from the BOSS DR12 sample, alongside Cosmic Microwave Background (CMB) data from Planck: from this dataset combination we infer H0 1/4 68.02+0.49 and the 2?? lower limit ?? > ???0.12, among the strongest limits ever reported on the DM-DE coupling strength ?? for the particular model considered. Contrary to what has been observed for the ??CDM model and simple extensions thereof, we find that the CMB + FS combination returns tighter constraints compared to the CMB + BAO one, suggesting that there is valuable additional information contained in the broadband of the power spectrum. We test this finding by running additional CMB-free analyses and removing sound horizon information, and discuss the important role of the equality scale in setting constraints on DM-DE interactions. Our results reinforce the critical role played by redshift-space galaxy clustering measurements in the epoch of precision cosmology, particularly in relation to tests of nonminimal dark sector extensions of the ??CDM model.
Address [Nunes, Rafael C.] Univ Fed Rio Grande Do Sul, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil, Email: rafadcnunes@gmail.com;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2470-0010 ISBN Medium
Area Expedition Conference
Notes WOS:000813312800005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5269
Permanent link to this record