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Author Coloma, P.; Huber, P.; Schwetz, T.
Title (down) Statistical interpretation of sterile neutrino oscillation searches at reactors Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 81 Issue 1 Pages 2 - 13pp
Keywords
Abstract A considerable experimental effort is currently under way to test the persistent hints for oscillations due to an eV-scale sterile neutrino in the data of various reactor neutrino experiments. The assessment of the statistical significance of these hints is usually based on Wilks' theorem, whereby the assumption is made that the log-likelihood is chi 2-distributed. However, it is well known that the preconditions for the validity of Wilks' theorem are not fulfilled for neutrino oscillation experiments. In this work we derive a simple asymptotic form of the actual distribution of the log-likelihood based on reinterpreting the problem as fitting white Gaussian noise. From this formalism we show that, even in the absence of a sterile neutrino, the expectation value for the maximum likelihood estimate of the mixing angle remains non-zero with attendant large values of the log-likelihood. Our analytical results are then confirmed by numerical simulations of a toy reactor experiment. Finally, we apply this framework to the data of the Neutrino-4 experiment and show that the null hypothesis of no-oscillation is rejected at the 2.6 sigma level, compared to 3.2 sigma obtained under the assumption that Wilks' theorem applies.
Address [Coloma, Pilar] Univ Autonoma Madrid, CSIC, Inst Fis Teor UAM, Calle Nicolas Cabrera 13-15, Madrid 28049, Spain, Email: pilar.coloma@ift.csic.es;
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:000606481000002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4680
Permanent link to this record
 
 
Author Foffa, S.; Mastrolia, P.; Sturani, R.; Sturm, C.; Bobadilla, W.J.T.
Title (down) Static Two-Body Potential at Fifth Post-Newtonian Order Type Journal Article
Year 2019 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 122 Issue 24 Pages 241605 - 6pp
Keywords
Abstract We determine the gravitational interaction between two compact bodies up to the sixth power in Newton's constant, G(N), in the static limit. This result is achieved within the effective field theory approach to general relativity, and exploits a manifest factorization property of static diagrams which allows us to derive static post Newtonian (PN) contributions of (2n + 1) order in terms of lower order ones. We recompute in this fashion the 1PN and 3PN static potential, and present the novel 5PN contribution.
Address [Foffa, Stefano] Univ Geneva, Dept Phys Theor, CH-1211 Geneva, Switzerland
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:000473033800003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4070
Permanent link to this record
 
 
Author Campanario, F.; Czyz, H.; Gluza, J.; Jelinski, T.; Rodrigo, G.; Tracz, S.; Zhuridov, D.
Title (down) Standard model radiative corrections in the pion form factor measurements do not explain the a(mu) anomaly Type Journal Article
Year 2019 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 100 Issue 7 Pages 076004 - 5pp
Keywords
Abstract In this paper, we address the question of whether the almost four standard deviations difference between theory and experiment for the muon anomalous magnetic moment a(mu) can be explained as a higher-order Standard Model perturbation effect in the pion form factor measurements. This question has, until now, remained open, obscuring the source of discrepancies between the measurements. We calculate the last radiative corrections for the extraction of the pion form factor, which were believed to be potentially substantial enough to explain the data within the Standard Model. We find that the corrections are too small to diminish existing discrepancies in the determination of the pion form factor for different kinematical configurations of low-energy BABAR, BES-III and KLOE experiments. Consequently, they cannot noticeably change the previous predictions for a(mu) and decrease the deviations between theory and direct measurements. To solve the above issues, new data and better understanding of low-energy experimental setups are needed, especially as new direct a(mu) measurements at Fermilab and J-PARC will provide new insights and substantially shrink the experimental error.
Address [Campanario, Francisco; Rodrigo, German; Tracz, Szymon] Univ Valencia, CSIC, Inst Fis Corpuscular, E-46980 Valencia, Spain, Email: henryk.czyz@us.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:000489577800008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4168
Permanent link to this record
 
 
Author Reig, M.; Srivastava, R.
Title (down) Spontaneous proton decay and the origin of Peccei-Quinn symmetry Type Journal Article
Year 2019 Publication Physics Letters B Abbreviated Journal Phys. Lett. B
Volume 790 Issue Pages 134-139
Keywords
Abstract We propose a new interpretation of Peccei-Quinn symmetry within the Standard Model, identifying it with the axial B+L symmetry i.e. U (1)(PQ) equivalent to U (1)(gamma 5)(B+L). This new interpretation retains all the attractive features of Peccei-Quinn solution to strong CP problem but in addition also leads to several other new and interesting consequences. Owing to the identification U (1)(PQ) equivalent to U (1)(gamma 5)(B+L) the axion also behaves like Majoron inducing small seesaw masses for neutrinos after spontaneous symmetry breaking. Another novel feature of this identification is the phenomenon of spontaneous (and also chiral) proton decay with its decay rate associated with the axion decay constant. Low energy processes which can be used to test this interpretation are pointed out.
Address [Reig, Mario; Srivastava, Rahul] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Parc Cient Paterna,C Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: mario.reig@ific.uv.es;
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0370-2693 ISBN Medium
Area Expedition Conference
Notes WOS:000460118200014 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3933
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Author Delhom, A.; Mariz, T.; Nascimento, J.R.; Olmo, G.J.; Petrov, A.Y.; Porfirio, P.J.
Title (down) Spontaneous Lorentz symmetry breaking and one-loop effective action in the metric-affine bumblebee gravity Type Journal Article
Year 2022 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 018 - 27pp
Keywords gravity; modified gravity; quantum field theory on curved space; Quantum fields in curved spacetimes
Abstract The metric-affine bumblebee model in the presence of fermionic matter minimally coupled to the connection is studied. We show that the model admits an Einstein frame representation in which the matter sector is described by a non-minimal Dirac action without any analogy in the literature. Such non-minimal terms involve unconventional couplings between the bumblebee and the fermion field. We then rewrite the quadratic fermion action in the Einstein frame in the basis of 16 Dirac matrices in order to identify the coefficients for Lorentz/CPT violation in all orders of the non-minimal coupling xi. The exact result for the fermionic determinant in the Einstein frame, including all orders in xi, is also provided. We demonstrate that the axial contributions are at least of second order in the perturbative expansion of xi. Furthermore, we compute the one-loop effective potential within the weak field approximation.
Address [Delhom, Adria] Univ Tartu, Inst Phys, Lab Theoret Phys, W Ostwaldi 1, EE-50411 Tartu, Estonia, Email: adria.delhom@gmail.com;
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:000834157900011 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5314
Permanent link to this record
 
 
Author del Rio, A.; Sanchis-Gual, N.; Mewes, V.; Agullo, I.; Font, J.A.; Navarro-Salas, J.
Title (down) Spontaneous Creation of Circularly Polarized Photons in Chiral Astrophysical Systems Type Journal Article
Year 2020 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 124 Issue 21 Pages 211301 - 6pp
Keywords
Abstract This work establishes a relation between chiral anomalies in curved spacetimes and the radiative content of the gravitational field. In particular, we show that a flux of circularly polarized gravitational waves triggers the spontaneous creation of photons with net circular polarization from the quantum vacuum. Using waveform catalogs, we identify precessing binary black holes as astrophysical configurations that emit such gravitational radiation and then solve the fully nonlinear Einstein's equations with numerical relativity to evaluate the net effect. The quantum amplitude for a merger is comparable to the Hawking emission rate of the final black hole and small to be directly observed. However, the implications for the inspiral of binary neutron stars could be more prominent, as argued on symmetry grounds.
Address [del Rio, Adrian; Sanchis-Gual, Nicolas] Univ Lisbon, Inst Super Tecn, Ctr Astrofis & Gravitacao CENTRA, Ave Rovisco Pais 1, P-1049001 Lisbon, Portugal
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:000535679100012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4407
Permanent link to this record
 
 
Author Alves, J.M.; Botella, F.J.; Miro, C.; Nebot, M.
Title (down) Spontaneous CP violation and μ-τ symmetry intwo-Higgs-doublet models with flavour conservation Type Journal Article
Year 2023 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 83 Issue 10 Pages 940 - 12pp
Keywords
Abstract In multi-Higgs-doublet models, requiring simultaneously that (i) CP violation only arises spontaneously, (ii)tree level scalar flavour changing couplings are absent and (iii) the fermion mixing matrix is CP violating, can only be achieved in a very specific manner. A general approach with new clarifying insights on the question is presented. Considering the quark sector, that peculiar possibility is not viable on phenomenological grounds. We show that, considering the lepton sector, it is highly interesting and leads to viable models with mu-tau symmetric PMNS matrices. Phenomenological implications of the models, both for Dirac and Majorana (in a type I seesaw scenario) neutrinos, are analysed.
Address [Miro, Carlos] Univ Valencia, Dept Fis Teor, CSIC, Valencia 46100, Spain, Email: j.magalhaes.alves@tecnico.ulisboa.pt;
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:001087967500002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5759
Permanent link to this record
 
 
Author Lazarides, G.; Reig, M.; Shafi, Q.; Srivastava, R.; Valle, J.W.F.
Title (down) Spontaneous Breaking of Lepton Number and the Cosmological Domain Wall Problem Type Journal Article
Year 2019 Publication Physical Review Letters Abbreviated Journal Phys. Rev. Lett.
Volume 122 Issue 15 Pages 151301 - 5pp
Keywords
Abstract We show that if global lepton number symmetry is spontaneously broken in a postinflation epoch, then it can lead to the formation of cosmological domain walls. This happens in the well-known “Majoron paradigm” for neutrino mass generation. We propose some realistic examples that allow spontaneous lepton number breaking to be safe from such domain walls.
Address [Lazarides, George] Aristotle Univ Thessaloniki, Sch Elect & Comp Engn, Fac Engn, Thessaloniki 54124, Greece, Email: lazaride@eng.auth.gr;
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:000464756200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3985
Permanent link to this record
 
 
Author Barenboim, G.; Park, W.I.
Title (down) Spontaneous baryogenesis in spiral inflation Type Journal Article
Year 2019 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 79 Issue 6 Pages 456 - 11pp
Keywords
Abstract We examined the possibility of spontaneous baryogenesis driven by the inflaton in the scenario of spiral inflation, and found the parametric dependence of the late-time baryon number asymmetry. As a result, it is shown that, depending on the effective coupling of baryon/lepton number violating operators, it is possible to obtain the right amount of asymmetry even in the presence of a matter-domination era as long as such era is relatively short. In a part of the parameter space, the required expansion rate during inflation is close to the current upper-bound, and hence can be probed in the near future experiments.
Address [Barenboim, Gabriela] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@uv.es;
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:000469517700001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4027
Permanent link to this record
 
 
Author Folgado, M.G.; Donini, A.; Rius, N.
Title (down) Spin-dependence of gravity-mediated dark matter in warped extra-dimensions Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 81 Issue 3 Pages 197 - 13pp
Keywords
Abstract We study the possibility that Dark Matter (DM) particles of spin 0, 1/2 or 1 may interact gravitationally with Standard Model (SM) particles within the framework of a warped Randall-Sundrum (RS) model. Both the Dark Matter and the Standard Model particles are assumed to be confined to the infra-red (IR) brane and only interchange Kaluza-Klein excitations of the graviton and the radion (adopting the Goldberger-Wise mechanism to stabilize the size of the extra-dimension). We analyze the different DM annihilation channels and find that the presently observed Dark Matter relic abundance, Omega DM, can be obtained within the freeze-out mechanism for DM particles of all considered spins. This extends our first work concerning scalar DM in RS scenarios (Folgado et al., in JHEP 01:161. https://doi.org/10.1007/JHEP01(2020)161, 2020) and put it on equal footing with our second work in which we studied DM particles of spin 0, 1/2 and 1 in the framework of the Clockwork/Linear Dilaton (CW/LD) model (Folgado et al., in JHEP 20:036. https://doi.org/10.1007/JHEP04(2020)036, 2020). We study the region of the model parameter space for which Omega DM is achieved and compare it with the different experimental and theoretical bounds. We find that, for DM particles mass mDM is an element of [1,15] TeV, most of the parameter space is excluded by the current constraints or will be excluded by the LHC Run III or by the LHC upgrade, the HL-LHC. The observed DM relic abundance can still be achieved for DM masses mDM is an element of [4,15] TeV and mG1<10 TeV for scalar and vector boson Dark Matter. On the other hand, for spin 1/2 fermion Dark Matter, only a tiny region with mDM<is an element of>[4,15] TeV, mG1 is an element of [5,10] TeV and Lambda >mG1 is compatible with theoretical and experimental bounds. We have also studied the impact of the radion in the phenomenology, finding that it does not modify significantly the allowed region for DM particles of any spin (differently from the CW/LD case, where its impact was quite significant in the case of scalar DM). We, eventually, briefly compare results in RS with those obtained in the CW/LD model.
Address [Folgado, Miguel G.] Univ Valencia, CSIC, Dept Fis Teor, C Catedratico Jose Beltran 2, Paterna 46980, Spain, Email: migarfol@ific.uv.es;
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:000625431000001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4767
Permanent link to this record