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Author Agius, D.; Essig, R.; Gaggero, D.; Scarcella, F.; Suczewski, G.; Valli, M.
Title Feedback in the dark: a critical examination of CMB bounds on primordial black holes Type Journal Article
Year 2024 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue (down) 7 Pages 003 - 36pp
Keywords accretion; cosmological parameters from CMBR; dark matter theory; primordial black holes
Abstract If present in the early universe, primordial black holes (PBHs) would have accreted matter and emitted high-energy photons, altering the statistical properties of the Cosmic Microwave Background (CMB). This mechanism has been used to constrain the fraction of dark matter that is in the form of PBHs to be much smaller than unity for PBH masses well above one solar mass. Moreover, the presence of dense dark matter mini -halos around the PBHs has been used to set even more stringent constraints, as these would boost the accretion rates. In this work, we critically revisit CMB constraints on PBHs taking into account the role of the local ionization of the gas around them. We discuss how the local increase in temperature around PBHs can prevent the dark matter mini -halos from strongly enhancing the accretion process, in some cases significantly weakening previously derived CMB constraints. We explore in detail the key ingredients of the CMB bound and derive a conservative limit on the cosmological abundance of massive PBHs.
Address [Agius, Dominic] Univ Valencia, CSIC, Inst Fis Corpuscular, C Catedrat Jose Beltran 2, E-46980 Paterna, Spain, Email: dominic.agius@ific.uv.es;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:001262242300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6187
Permanent link to this record
 
 
Author Alkofer, R.; Llanes-Estrada, F.J.; Salas-Bernardez, A.
Title Spinning pairs: Supporting 3P0 quark-pair creation from Landau-gauge Green's functions Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue (down) 7 Pages 074015 - 21pp
Keywords
Abstract Abundant phenomenology suggests that strong decays from relatively low-excitation hadrons into other hadrons proceed by the creation of a light quark-antiquark pair with zero total angular momentum, the so called 3P0 mechanism originating from a scalar bilinear. Yet the quantum chromodynamics (QCD) interaction is perturbatively mediated by gluons of spin one, and QCD presents a chirally symmetric Lagrangian. Such scalar decay term must be spontaneously generated upon breaking chiral symmetry. We attempt to reproduce this with the help of the quark-gluon vertex in Landau gauge, whose nonperturbative structure has been reasonably elucidated in the last years, and insertions of a uniform, constant chromoelectric field. This is akin to Schwinger pair production in quantum electrodynamics (QED), and we provide a comparison with its two field-insertions diagram. We find that, the symmetry being cylindrical, the adequate quantum numbers to discuss the production are rather 3E0, 3E1, and 3110 as in diatomic molecules, and we indeed find a sizeable contribution of the third decay mechanism, which may give a rationale for the 3P0 phenomenology, as long as the momentum of the produced pair is at or below the scale of the bare or dynamically generated fermion mass. On the other hand, ultrarelativistic fermions are rather ejected with 3E1 quantum numbers. In QED, our results suggest that 3E0 dominates, whereas the constraint of producing a color singlet in QCD leads to 3110 dominance at sub-GeV momenta.
Address [Alkofer, Reinhard] Karl Franzens Univ Graz, Inst Phys, NAWI Graz, Univ Pl 5, A-8010 Graz, Austria
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:001235870400019 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6189
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Author Aguilar, A.C.; Ferreira, M.N.; Papavassiliou, J.; Santos, L.R.
Title Four-gluon vertex in collinear kinematics Type Journal Article
Year 2024 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 84 Issue (down) 7 Pages 676 - 27pp
Keywords
Abstract To date, the four-gluon vertex is the least explored component of the QCD Lagrangian, mainly due to the vast proliferation of Lorentz and color structures required for its description. In this work we present a nonperturbative study of this vertex, based on the one-loop dressed Schwinger-Dyson equation obtained from the 4PI effective action. A vast simplification is brought about by resorting to “collinear” kinematics, where all momenta are parallel to each other, and by appealing to the charge conjugation symmetry in order to eliminate certain color structures. Out of the fifteen form factors that comprise the transversely-projected version of this vertex, two are singled out and studied in detail; the one associated with the classical tensorial structure is moderately suppressed in the infrared regime, while the other diverges logarithmically at the origin. Quite interestingly, both form factors display the property known as “planar degeneracy” at a rather high level of accuracy. With these results we construct an effective charge that quantifies the strength of the four-gluon interaction, and compare it with other vertex-derived charges from the gauge sector of QCD.
Address [Aguilar, A. C.; Santos, L. R.] Univ Campinas UNICAMP, Inst Phys Gleb Wataghin, BR-13083859 Campinas, SP, Brazil, Email: aguilar@ifi.unicamp.br
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:001264786100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6199
Permanent link to this record
 
 
Author Centelles Chulia, S.; Herrero-Brocal, A.; Vicente, A.
Title The Type-I Seesaw family Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 07 Issue (down) 7 Pages 060 - 35pp
Keywords Lepton Flavour Violation (charged); New Light Particles; Non-Standard Neutrino Properties; Specific BSM Phenomenology
Abstract We provide a comprehensive analysis of the Type-I Seesaw family of neutrino mass models, including the conventional type-I seesaw and its low-scale variants, namely the linear and inverse seesaws. We establish that all these models essentially correspond to a particular form of the type-I seesaw in the context of explicit lepton number violation. We then focus into the more interesting scenario of spontaneous lepton number violation, systematically categorizing all inequivalent minimal models. Furthermore, we identify and flesh out specific models that feature a rich majoron phenomenology and discuss some scenarios which, despite having heavy mediators and being invisible in processes such as μ-> e gamma, predict sizable rates for decays including the majoron in the final state.
Address [Centelles Chulia, Salvador] Max Planck Inst Kernphys, Saupfercheckweg 1, D-69117 Heidelberg, Germany, Email: chulia@mpi-hd.mpg.de;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001264784900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6201
Permanent link to this record
 
 
Author Sorelli, G.; Gessner, M.; Treps, N.; Walschaers, M.
Title Gaussian quantum metrology for mode-encoded parameters Type Journal Article
Year 2024 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 26 Issue (down) 7 Pages 073022 - 23pp
Keywords quantum metrology; multimode quantum optics; Gaussian states
Abstract Quantum optical metrology aims to identify ultimate sensitivity bounds for the estimation of parameters encoded into quantum states of the electromagnetic field. In many practical applications, including imaging, microscopy, and remote sensing, the parameter of interest is not only encoded in the quantum state of the field, but also in its spatio-temporal distribution, i.e. in its mode structure. In this mode-encoded parameter estimation setting, we derive an analytical expression for the quantum Fisher information valid for arbitrary multimode Gaussian fields. To illustrate the power of our approach, we apply our results to the estimation of the transverse displacement of a beam and to the temporal separation between two pulses. For these examples, we show how the estimation sensitivity can be enhanced by adding squeezing into specific modes.
Address [Sorelli, Giacomo; Treps, Nicolas; Walschaers, Mattia] Sorbonne Univ, ENS Univ PSL, CNRS, Lab Kastler Brossel,Coll France, 4 Pl Jussieu, F-75252 Paris, France, Email: giacomo.sorelli@iosb-extern.fraunhofer.de
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:001270966100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6209
Permanent link to this record
 
 
Author Bayar, M.; Molina, R.; Oset, E.; Liu, M.Z.; Geng, L.S.
Title Subtleties in triangle loops for Ds+ → ρ+ η → π+ π0 η in a0(980) production Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue (down) 7 Pages 076027 - 7pp
Keywords
Abstract We address a general problem in the evaluation of triangle loops stemming from the consideration of the range of the interaction involved in some of the vertices, as well as the energy dependence of the width of some unstable particles in the loop. We find sizeable corrections from both effects. We apply that to a loop relevant to the D + s -> pi + pi 0 eta decay, and find reductions of about a factor of 4 in the mass distribution of invariant mass of the pi eta in the region of the a 0 ( 980 ) . The method used is based on the explicit analytical evaluation of the q 0 integration in the d 4 q loop integration, using Cauchy 's residues method, which at the same time offers an insight on the convergence of the integrals and the effect of form factors and cutoffs.
Address [Bayar, M.] Kocaeli Univ, Dept Phys, TR-41380 Izmit, Turkiye, Email: melahat.bayar@kocaeli.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:001236271000017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6211
Permanent link to this record
 
 
Author Xiao, C.W.; Dias, J.M.; Dai, L.R.; Liang, W.H.; Oset, E.
Title Triangle singularity in the J/ψ → ϕ π+ a−0(π−η) ,ϕ π− a+0(π+η) decays Type Journal Article
Year 2024 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 109 Issue (down) 7 Pages 074033 - 11pp
Keywords
Abstract We study the J= psi -> phi pi + a 0 ( 980 ) – ( a – 0 -> pi – eta ) decay, evaluating the double mass distribution in terms of the pi – eta and pi + a – 0 invariant masses. We show that the pi – eta mass distribution exhibits the typical cusp structure of the a 0 ( 980 ) seen in recent high statistics experiments, and the pi + a – 0 spectrum shows clearly a peak around M inv ( pi + a – 0 ) = 1420 MeV, corresponding to a triangle singularity. When integrating over the two invariant masses we find a branching ratio for this decay of the order of 10 – 5 , which is easily accessible in present laboratories. We also call attention to the fact that the signal obtained is compatible with a bump experimentally observed in the eta pi + pi – mass distribution in the J= psi -> phi eta pi + pi – decay and encourage further analysis to extract from there the phi pi + a – 0 and phi pi – a + 0 decay modes.
Address [Xiao, C. W.; Liang, W. H.; Oset, E.] Guangxi Normal Univ, Dept Phys, Guilin 541004, Peoples R China, Email: xiaochw@gxnu.edu.cn;
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:001236271000012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6212
Permanent link to this record
 
 
Author Timar, J. et al; Algora, A.
Title Experimental Evidence for Transverse Wobbling in Pd-105 Type Journal Article
Year 2019 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 122 Issue (down) 6 Pages 062501 - 6pp
Keywords
Abstract New rotational bands built on the nu(h(11/2)) configuration have been identified in Pd-105. Two bands built on this configuration show the characteristics of transverse wobbling: the Delta I = 1 transitions between them have a predominant E2 component and the wobbling energy decreases with increasing spin. The properties of the observed wobbling bands are in good agreement with theoretical results obtained using constrained triaxial covariant density functional theory and quantum particle rotor model calculations. This provides the first experimental evidence for transverse wobbling bands based on a one-neutron configuration, and also represents the first observation of wobbling motion in the A similar to 100 mass region.
Address [Timar, J.; Kruzsicz, B.; Sohler, D.; Kuti, I.; Algora, A.; Dombradi, Zs.; Krasznahorkay, A.; Molnar, J.; Nyako, B. M.; Zolnai, L.] Hungarian Acad Sci, Inst Nucl Res, Pf 51, H-4001 Debrecen, Hungary, Email: timar@atomki.hu
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 0031-9007 ISBN Medium
Area Expedition Conference
Notes WOS:000458381300006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3909
Permanent link to this record
 
 
Author Alvarez-Castillo, D.E.; Blaschke, D.B.; Grunfeld, A.G.; Pagura, V.P.
Title Third family of compact stars within a nonlocal chiral quark model equation of state Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue (down) 6 Pages 063010 - 19pp
Keywords
Abstract A class of hybrid compact star equations of state is investigated that joins by a Maxwell construction a low-density phase of hadronic matter, modeled by a relativistic mean-field approach with excluded nucleon volume, with a high-density phase of color superconducting two-flavor quark matter, described within a nonlocal covariant chiral quark model. It is found that the occurrence of a stable branch of hybrid compact stars requires a nonvanishing vector meson coupling in the quark model that exceeds a minimal value which depends on the presence of a diquark condensate. It is shown that these hybrid stars do not form a third family disconnected from the second family of ordinary neutron stars unless additional (de) confining effects are introduced with a density-dependent bag pressure. A suitably chosen density dependence of the vector meson coupling assures that at the same time the 2M(circle dot) maximum mass constraint is fulfilled on the hybrid star branch. A twofold interpolation method is realized which implements both the density dependence of a confining bag pressure at the onset of the hadron-to-quark matter transition and the stiffening of quark matter at higher densities by a density-dependent vector meson coupling. For three parametrizations of this class of hybrid equation of state the properties of corresponding compact star sequences are presented, including mass twins of neutron and hybrid stars at 2.00, 1.39 and 1.20 M-circle dot, respectively, and the hybrid compact star (third) families. The sensitivity of the hybrid equation of state and the corresponding compact star sequences to variations of the interpolation parameters at the 10% level is investigated and it is found that the feature of third family solutions for compact stars is robust against such a variation. This advanced description of hybrid star matter allows us to interpret GW170817 as a merger not only of two neutron stars but also of a neutron star with a hybrid star or of two hybrid stars.
Address [Alvarez-Castillo, D. E.; Blaschke, D. B.] Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Joliot Curie St 6, Dubna 141980, Russia, Email: alvarez@theor.jinr.ru;
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:000461909600002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3947
Permanent link to this record
 
 
Author Nascimento, J.R.; Olmo, G.J.; Porfirio, P.J.; Petrov, A.Y.; Soares, A.R.
Title Global monopole in Palatini f(R) gravity Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 99 Issue (down) 6 Pages 064053 - 11pp
Keywords
Abstract We consider the space-time metric generated by a global monopole in an extension of general relativity (GR) of the form f(R) = R – lambda R-2. The theory is formulated in the metric-affine (or Palatini) formalism, and exact analytical solutions are obtained. For lambda < 0, one finds that the solution has the same characteristics as the Schwarzschild black hole with a monopole charge in Einstein's GR. For lambda > 0, instead, the metric is more closely related to the Reissner-Nordstrom metric with a monopole charge and, in addition, it possesses a wormhole-like structure that allows for the geodesic completeness of the spacetime. Our solution recovers the expected limits when lambda = 0 and also at the asymptotic far limit. The angular deflection of light in this space-time in the weak field regime is also calculated.
Address [Nascimento, J. R.; Petrov, A. Yu; Soares, A. R.] Univ Fed Paraiba, Dept Fis, Caixa Postal 5008, BR-58051970 Joao Pessoa, Paraiba, Brazil, Email: jroberto@fisica.ufpb.br;
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:000462920100010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3966
Permanent link to this record