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Author (up) Binosi, D.; Mezrag, C.; Papavassiliou, J.; Roberts, C.D.; Rodriguez-Quintero, J.
Title Process-independent strong running coupling Type Journal Article
Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 96 Issue 5 Pages 054026 - 7pp
Keywords
Abstract We unify two widely different approaches to understanding the infrared behavior of quantum chromodynamics (QCD), one essentially phenomenological, based on data, and the other computational, realized via quantum field equations in the continuum theory. Using the latter, we explain and calculate a process-independent running coupling for QCD, a new type of effective charge that is an analogue of the Gell-Mann-Low effective coupling in quantum electrodynamics. The result is almost identical to the process-dependent effective charge defined via the Bjorken sum rule, which provides one of the most basic constraints on our knowledge of nucleon spin structure. This reveals the Bjorken sum to be a near direct means by which to gain empirical insight into QCD's Gell-Mann-Low effective charge.
Address [Binosi, Daniele] European Ctr Theoret Studies Nucl Phys & Related, Str Tabarelle 286, I-38123 Villazzano, Trentino, Italy
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:000411579700005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3317
Permanent link to this record
 
 
Author (up) Binosi, D.; Papavassiliou, J.
Title Coupled dynamics in gluon mass generation and the impact of the three-gluon vertex Type Journal Article
Year 2018 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 97 Issue 5 Pages 054029 - 15pp
Keywords
Abstract We present a detailed study of the subtle interplay transpiring at the level of two integral equations that are instrumental for the dynamical generation of a gluon mass in pure Yang-Mills theories. The main novelty is the joint treatment of the Schwinger-Dyson equation governing the infrared behavior of the gluon propagator and of the integral equation that controls the formation of massless bound-state excitations, whose inclusion is instrumental for obtaining massive solutions from the former equation. The self-consistency of the entire approach imposes the requirement of using a single value for the gauge coupling entering in the two key equations; its fulfilment depends crucially on the details of the three-gluon vertex, which contributes to both of them, but with different weight. In particular, the characteristic suppression of this vertex at intermediate and low energies enables the convergence of the iteration procedure to a single gauge coupling, whose value is reasonably close to that extracted from related lattice simulations.
Address [Binosi, Daniele] European Ctr Theoret Studies Nucl Phys & Related, Str Tabarelle 286, I-38123 Villazzano, Trento, Italy
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:000428240900006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3535
Permanent link to this record
 
 
Author (up) Biswas, A.; Sinha, N.; Abbas, G.
Title Nonleptonic decays of charmed mesons into two pseudoscalars Type Journal Article
Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 92 Issue 1 Pages 014032 - 16pp
Keywords
Abstract We examine the role of resonant coupled channel final state interactions (FSIs), as well as weak annihilation and exchange contributions, in explaining all the two-body hadronic D -> PP decay modes. In the un-unitarized amplitudes we include modified Wilson coefficients with nonfactorizable corrections as parameters. For the hadronic form factors, the z-series expansion method is used to get the q(2) dependence. The FSI effects are incorporated via a phenomenological approach with widths of resonances to various channels taken from observations where available, and others as additional parameters to be determined from fits of all the theoretical rates to the measured ones. Our results for the rather hard to explain D-0 -> K+K-, pi(+)pi(-) are in agreement with measured values. We demonstrate that both weak exchange and FSI effects are required to get the correct branching ratio for the D-0 -> K-0(K) over bar (0) mode. Using our unitarized amplitudes we evaluate the strong phase difference between the amplitudes for D-0 -> K-pi(+) and D-0 -> K+pi(-) and find it to be in complete agreement with the recent BES III result.
Address [Biswas, Aritra; Sinha, Nita] Inst Math Sci, Madras 600113, Tamil Nadu, India
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000358605200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2335
Permanent link to this record
 
 
Author (up) Blas, D.; Witte, S.J.
Title Imprints of axion superradiance in the CMB Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 10 Pages 103018 - 10pp
Keywords
Abstract Light axions (m(a) less than or similar to 10(-10) eV) can form dense clouds around rapidly rotating astrophysical black holes via a mechanism known as rotational superradiance. The coupling between axions and photons induces a parametric resonance, arising from the stimulated decay of the axion cloud, which can rapidly convert regions of large axion number densities into an enormous flux of low-energy photons. In this work we consider the phenomenological implications of a superradiant axion cloud undergoing resonant decay. We show that the low-energy photons produced from such events will be absorbed over cosmologically short distances, potentially inducing massive shockwaves that heat and ionize the intergalactic medium over Mpc scales. These shockwaves may leave observable imprints in the form of anisotropic spectral distortions or inhomogeneous features in the optical depth.
Address [Blas, Diego] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: diego.blas@kcl.ac.uk;
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:000589606900004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4609
Permanent link to this record
 
 
Author (up) Blas, D.; Witte, S.J.
Title Quenching mechanisms of photon superradiance Type Journal Article
Year 2020 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 102 Issue 12 Pages 123018 - 10pp
Keywords
Abstract Rapidly rotating black holes are known to develop instabilities in the presence of a sufficiently light boson, a process which becomes efficient when the boson's Compton wavelength is roughly the size of the black hole. This phenomenon known as black hole superradiance generates an exponentially growing boson cloud at the expense of the rotational energy of the black hole. For astrophysical black holes with M similar to O(10)M-circle dot, the superradiant condition is achieved for bosons with m(b) similar to O(10(-11))eV; intriguingly, photons traversing the intergalactic medium acquire an effective mass (due to their interactions with the ambient plasma) which naturally resides in this range. The implications of photon superradiance, i.e., the evolution of the superradiant photon cloud and ambient plasma in the presence of scattering and particle production processes, have yet to be thoroughly investigated. Here, we enumerate and discuss a number of different processes capable of quenching the growth of the photon cloud, including particle interactions with the ambient electrons and backreactions on the effective mass (arising e.g., from thermal effects, pair production, ionization of the local background, and modifications to the dispersion relation from strong electric fields). This work naturally serves as a guide in understanding how interactions may allow light exotic bosons to evade superradiant constraints.
Address [Blas, Diego] Kings Coll London, Dept Phys, Theoret Particle Phys & Cosmol Grp, London WC2R 2LS, England, Email: diego.blas@kcl.ac.uk;
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:000599093100002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4666
Permanent link to this record
 
 
Author (up) Bodeker, D.; Kuhnel, F.; Oldengott, I.M.; Schwarz, D.J.
Title Lepton flavor asymmetries and the mass spectrum of primordial black holes Type Journal Article
Year 2021 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 103 Issue 6 Pages 063506 - 6pp
Keywords
Abstract We study the influence of lepton flavor asymmetries on the formation and the mass spectrum of primordial black holes. We estimate the detectability of their mergers with LIGO/Virgo and show that the currently published gravitational wave events may actually be described by a primordial black hole spectrum from nonzero asymmetries. We suggest to use gravitational-wave astronomy as a novel tool to probe how lepton flavor asymmetric the Universe has been before the onset of neutrino oscillations.
Address [Boedeker, Dietrich; Schwarz, Dominik J.] Univ Bielefeld, Fak Phys, Postfach 100131, D-33501 Bielefeld, Germany, Email: bodeker@physik.uni-bielefeld.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:000627581200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4761
Permanent link to this record
 
 
Author (up) Bodenstein, S.; Bordes, J.; Dominguez, C.A.; Peñarrocha, J.; Schilcher, K.
Title Bottom-quark mass from finite energy QCD sum rules Type Journal Article
Year 2012 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 85 Issue 3 Pages 034003 - 5pp
Keywords
Abstract Finite energy QCD sum rules involving both inverse-and positive-moment integration kernels are employed to determine the bottom-quark mass. The result obtained in the (MS) over bar scheme at a reference scale of 10 GeV is m (m) over bar (b)(10 GeV) = 3623(9) MeV. This value translates into a scale-invariant mass (m) over bar (b)((m) over bar (b)) = 4171(9) MeV. This result has the lowest total uncertainty of any method, and is less sensitive to a number of systematic uncertainties that affect other QCD sum rule determinations.
Address [Bodenstein, S.; Dominguez, C. A.; Schilcher, K.] Univ Cape Town, Ctr Theoret & Math Phys, ZA-7700 Rondebosch, South Africa
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000299938300002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 896
Permanent link to this record
 
 
Author (up) Bodenstein, S.; Bordes, J.; Dominguez, C.A.; Peñarrocha, J.; Schilcher, K.
Title QCD sum rule determination of the charm-quark mass Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 83 Issue 7 Pages 074014 - 4pp
Keywords
Abstract QCD sum rules involving mixed inverse moment integration kernels are used in order to determine the running charm-quark mass in the (MS) over bar scheme. Both the high and the low energy expansion of the vector current correlator are involved in this determination. The optimal integration kernel turns out to be of the form p(s) = 1 -(s(0)/s)(2), where s(0) is the onset of perturbative QCD. This kernel enhances the contribution of the well known narrow resonances, and reduces the impact of the data in the range s similar or equal to 20-25 GeV2. This feature leads to a substantial reduction in the sensitivity of the results to changes in s(0), as well as to a much reduced impact of the experimental uncertainties in the higher resonance region. The value obtained for the charm-quark mass in the (MS) over bar scheme at a scale of 3 GeV is (m) over bar (c)(3 GeV) = 987 +/- 9 MeV, where the error includes all sources of uncertainties added in quadrature.
Address [Bodenstein, S.; Dominguez, C. A.] Univ Cape Town, Ctr Theoret & Math Phys, ZA-7700 Rondebosch, South Africa
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000289519700002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 604
Permanent link to this record
 
 
Author (up) 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
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
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 1550-7998 ISBN Medium
Area Expedition Conference
Notes ISI:000286567000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 527
Permanent link to this record
 
 
Author (up) Boito, D.; Cata, O.; Golterman, M.; Jamin, M.; Maltman, K.; Osborne, J.; Peris, S.
Title New determination of alpha(s) from hadronic tau decays Type Journal Article
Year 2011 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 84 Issue 11 Pages 113006 - 19pp
Keywords
Abstract We present a new framework for the extraction of the strong coupling from hadronic tau decays through finite-energy sum rules. Our focus is on the small, but still significant nonperturbative effects that, in principle, affect both the central value and the systematic error. We employ a quantitative model in order to accommodate violations of quark-hadron duality, and enforce a consistent treatment of the higher-dimensional contributions of the operator product expansion to our sum rules. Using 1998 OPAL data for the nonstrange isovector vector and axial-vector spectral functions, we find the n(f) = 3 values alpha(s)(m(tau)(2)) = 0.307 +/- 0.019 in fixed-order perturbation theory, and 0.322 +/- 0.026 in contour-improved perturbation theory. For comparison, the original OPAL analysis of the same data led to the values 0.324 +/- 0.014 (fixed order) and 0.348 +/- 0.021 (contour improved).
Address [Boito, Diogo] Univ Autonoma Barcelona, Dept Fis, E-08193 Barcelona, 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 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000298131000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 847
Permanent link to this record