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Author Wang, Y.F.; Yao, D.L.; Zheng, H.Q. url  doi
openurl 
  Title On the existence of N*(890) resonance in S-11 channel of N scatterings Type Journal Article
  Year 2019 Publication Frontiers of Physics Abbreviated Journal Front. Phys.  
  Volume 14 Issue 2 Pages 24501 - 6pp  
  Keywords dispersion relations; N scatterings; nucleon resonance  
  Abstract Low-energy partial-wave N scattering data is reexamined with the help of the production representation of partial-wave S matrix, where branch cuts and poles are thoroughly under consideration. The left-hand cut contribution to the phase shift is determined, with controlled systematic error estimates, by using the results of O(p(3)) chiral perturbative amplitudes obtained in the extended-onmass- shell scheme. In S-11 and P-11 channels, severe discrepancies are observed between the phase shift data and the sum of all known contributions. Statistically satisfactory fits to the data can only be achieved by adding extra poles in the two channels. We find that a S-11 resonance pole locates at zr = (0:895-0:081)-(0:164-0:023)i GeV, on the complex s-plane. On the other hand, a P-11 virtual pole, as an accompanying partner of the nucleon bound-state pole, locates atzv = (0:966-0:018) GeV, slightly above the nucleon pole on the real axis below threshold. Physical origin of the two newly established poles is explored to the best of our knowledge. It is emphasized that the O(p(3)) calculation greatly improves the fit quality comparing with the previous O(p(2)) one.  
  Address (down) [Wang, Yu-Fei; Zheng, Han-Qing] Peking Univ, Dept Phys, Beijing 100871, Peoples R China, Email: deliang.yao@ific.uv.es  
  Corporate Author Thesis  
  Publisher Higher Education Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2095-0462 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000454564100001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3857  
Permanent link to this record
 
 
Author Wang, D. url  doi
openurl 
  Title Model-independent traversable wormholes from baryon acoustic oscillations Type Journal Article
  Year 2023 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe  
  Volume 42 Issue Pages 101306 - 8pp  
  Keywords Traversable wormholes; Dark energy; Baryon acoustic oscillations  
  Abstract In this paper, we investigate the model-independent traversable wormholes from baryon acoustic oscillations. Firstly, we place the statistical constraints on the average dark energy equation of state Wav by only using BAO data. Subsequently, two specific wormhole solutions are obtained, i.e, the cases of the constant redshift function and a special choice for the shape function. For the first case, we analyze the traversabilities of the wormhole configuration, and for the second case, we find that one can construct theoretically a traversable wormhole with infinitesimal amounts of average null energy condition violating phantom fluid. Furthermore, we perform the stability analysis for the first case, and find that the stable equilibrium configurations may increase for increasing values of the throat radius of the wormhole in the cases of a positive and a negative surface energy density. It is worth noting that the obtained wormhole solutions are static and spherically symmetrical metric, and that we assume Wav to be a constant between different redshifts when placing constraints, hence, these wormhole solutions can be interpreted as stable and static phantom wormholes configurations at some certain redshift which lies in the range [0.32, 2.34].  
  Address (down) [Wang, Deng] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46980 Paterna, Spain, Email: cstar@nao.cas.cn  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001122744700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5853  
Permanent link to this record
 
 
Author Wagner, C.; Verde, L.; Boubekeur, L. url  doi
openurl 
  Title N-body simulations with generic non-Gaussian initial conditions I: power spectrum and halo mass function Type Journal Article
  Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 10 Issue 10 Pages 022 - 24pp  
  Keywords power spectrum; cosmological simulations; initial conditions and eternal universe; galaxy clusters  
  Abstract We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one). We plan to make the simulations outputs available to the community via the non-Gaussian simulations comparison project web site http://icc.ub.edu/similar to liciaverde/NGSCP.html.  
  Address (down) [Wagner, Christian; Verde, Licia] Univ Barcelona, ICCUB IEEC, E-08028 Barcelona, Spain, Email: cwagner@icc.ub.edu  
  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 ISI:000283577600013 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 339  
Permanent link to this record
 
 
Author Vitez-Sveiczer, A. et al; Algora, A.; Morales, A.I.; Rubio, B.; Agramunt, J.; Guadilla, V.; Montaner-Piza, A.; Orrigo, S.E.A. doi  openurl
  Title The beta-decay of Kr-70 into Br-70: Restoration of the pseudo-SU(4) symmetry Type Journal Article
  Year 2022 Publication Physics Letters B Abbreviated Journal Phys. Lett. B  
  Volume 830 Issue Pages 137123 - 8pp  
  Keywords Beta decay of Kr-70; pn pairing; GT strength distribution; Pseudo-SU(4) symmetry; QRPA calculations  
  Abstract The beta-decay of the even-even nucleus Kr-70 with Z=N+2, has been investigated at the Radioactive Ion Beam Factory (RIBF) of the RIKEN Nishina Center using the BigRIPS fragment separator, the ZeroDegree Spectrometer, the WAS3ABI implantation station and the EURICA HPGe cluster array. Fifteen gamma-rays associated with the beta-decay of( 70)Kr into Br-70 have been identified for the first time, defining ten populated states below E-exc=3300 keV. The half-life of Kr-70 was derived with increased precision and found to be t(1/2)=45.19 +/- 0.14 ms. The beta-delayed proton emission probability has also been determined as epsilon(p)=0.545(23)%. An increase in the beta-strength to the yrast 1(+) state in comparison with the heaviest Z=N+2 system studied so far (Ge-62 decay) is observed that may indicate increased np correlations in the T=0 channel. The beta-decay strength deduced from the results is interpreted in terms of the proton-neutron quasiparticle random-phase approximation (pnQRPA) and also with a schematic model that includes isoscalar and isovector pairing in addition to quadrupole deformation. The application of this last model indicates an approximate realization of pseudo-SU(4) symmetry in this system.  
  Address (down) [Vitez-Sveiczer, A.; Algora, A.; Morales, A., I; Rubio, B.; Agramunt, J.; Guadilla, V; Montaner-Piza, A.; Orrigo, S. E. A.; Gelletly, W.] Univ Valencia, Inst Fis Corpuscular, CSIC, E-46071 Valencia, Spain, Email: algora@ific.uv.es;  
  Corporate Author Thesis  
  Publisher Elsevier 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:000832707200002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5316  
Permanent link to this record
 
 
Author Vinyoles, N.; Serenelli, A.M.; Villante, F.L.; Basu, S.; Bergstrom, J.; Gonzalez-Garcia, M.C.; Maltoni, M.; Pena-Garay, C.; Song, N.Q. url  doi
openurl 
  Title A New Generation of Standard Solar Models Type Journal Article
  Year 2017 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.  
  Volume 835 Issue 2 Pages 202 - 16pp  
  Keywords neutrinos; Sun: abundances; Sun: Helioseismology; Sun: interior  
  Abstract We compute a new generation of standard solar models (SSMs) that includes recent updates on some important nuclear reaction rates and a more consistent treatment of the equation of state. Models also include a novel and flexible treatment of opacity uncertainties based on opacity kernels, required in. light of recent theoretical and experimental works on radiative opacity. Two large sets of SSMs, each based on a different canonical set of solar abundances with high and low metallicity (Z), are computed to determine model uncertainties and correlations among different observables. We present detailed comparisons of high-and low-Z models against different ensembles of solar observables,. including solar neutrinos, surface helium abundance, depth of the. convective envelope, and sound speed profile. A global comparison, including all observables, yields a p-value of 2.7 sigma for the high-Z model and 4.7 sigma for the low-Z one. When the sound speed differences in the narrow region of 0.65 < r/R-circle dot < 0.70 are excluded from the analysis, results are 0.9 sigma and 3.0 sigma for high-and low-Z models respectively. These results show that. high-Z models agree well with solar data but have a systematic problem right below the bottom of the convective envelope linked to steepness of molecular weight and temperature gradients, and that low-Z models lead to a much more general disagreement with solar data. We also show that, while simple parametrizations of opacity uncertainties can strongly alleviate the solar abundance problem, they are insufficient to substantially improve the agreement of SSMs with helioseismic data beyond that obtained for high-Z models due to the intrinsic correlations of theoretical predictions.  
  Address (down) [Vinyoles, Nuria; Serenelli, Aldo M.] CSIC IEEC, Inst Ciencies Espai, Campus UAB,Carrer Can Magrans S-N, E-08193 Barcelona, Spain, Email: vinyoles@ice.csic.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 0004-637x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000401145700018 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3145  
Permanent link to this record
 
 
Author Vincent, A.C.; Fernandez Martinez, E.; Hernandez, P.; Mena, O.; Lattanzi, M. url  doi
openurl 
  Title Revisiting cosmological bounds on sterile neutrinos Type Journal Article
  Year 2015 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 04 Issue 4 Pages 006 - 23pp  
  Keywords particle physics – cosmology connection; cosmological neutrinos; cosmology of theories beyond the SM  
  Abstract We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R-CMB and the sound horizon r(s) from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin(2) theta less than or similar to 0.026(m(s)/eV)(-2).  
  Address (down) [Vincent, Aaron C.] Univ Durham, Dept Phys, IPPP, Durham DH1 3LE, England, Email: aaron.vincent@durham.ac.uk;  
  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:000355742500007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2261  
Permanent link to this record
 
 
Author Vincent, A.C.; Scott, P.; Trampedach, R. url  doi
openurl 
  Title Light bosons in the photosphere and the solar abundance problem Type Journal Article
  Year 2013 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 432 Issue 4 Pages 3332-3339  
  Keywords elementary particles; line: formation; Sun: abundances; Sun: atmosphere; cosmology: theory  
  Abstract Spectroscopy is used to measure the elemental abundances in the outer layers of the Sun, whereas helioseismology probes the interior. It is well known that current spectroscopic determinations of the chemical composition are starkly at odds with the metallicity implied by helioseismology. We investigate whether the discrepancy may be due to conversion of photons to a new light boson in the solar photosphere. We examine the impact of particles with axion-like interactions with the photon on the inferred photospheric abundances, showing that resonant axion-photon conversion is not possible in the region of the solar atmosphere in which line formation occurs. Although non-resonant conversion in the line-forming regions can in principle impact derived abundances, constraints from axion-photon conversion experiments rule out the couplings necessary for these effects to be detectable. We show that this extends to hidden photons and chameleons (which would exhibit similar phenomenological behaviour), ruling out known theories of new light bosons as photospheric solutions to the solar abundance problem.  
  Address (down) [Vincent, A. C.] Univ Valencia, IFIC, CSIC, E-46071 Valencia, Spain, Email: vincent@ific.uv.es  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000321053500058 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1481  
Permanent link to this record
 
 
Author Villanueva-Domingo, P.; Villaescusa-Navarro, F. url  doi
openurl 
  Title Removing Astrophysics in 21 cm Maps with Neural Networks Type Journal Article
  Year 2021 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.  
  Volume 907 Issue 1 Pages 44 - 14pp  
  Keywords Cosmology; Cold dark matter; Dark matter; Dark matter distribution; H I line emission; Intergalactic medium; Cosmological evolution; Convolutional neural networks; Large-scale structure of the universe  
  Abstract Measuring temperature fluctuations in the 21 cm signal from the epoch of reionization and the cosmic dawn is one of the most promising ways to study the universe at high redshifts. Unfortunately, the 21 cm signal is affected by both cosmology and astrophysics processes in a nontrivial manner. We run a suite of 1000 numerical simulations with different values of the main astrophysical parameters. From these simulations we produce tens of thousands of 21 cm maps at redshifts 10 <= z <= 20. We train a convolutional neural network to remove the effects of astrophysics from the 21 cm maps and output maps of the underlying matter field. We show that our model is able to generate 2D matter fields not only that resemble the true ones visually but whose statistical properties agree with the true ones within a few percent down to scales 2 Mpc(-1). We demonstrate that our neural network retains astrophysical information that can be used to constrain the value of the astrophysical parameters. Finally, we use saliency maps to try to understand which features of the 21 cm maps the network is using in order to determine the value of the astrophysical parameters.  
  Address (down) [Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: Pablo.Villanueva@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 0004-637x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000612333400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4698  
Permanent link to this record
 
 
Author Villanueva-Domingo, P.; Gnedin, N.Y.; Mena, O. url  doi
openurl 
  Title Warm Dark Matter and Cosmic Reionization Type Journal Article
  Year 2018 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.  
  Volume 852 Issue 2 Pages 139 - 7pp  
  Keywords cosmology: theory; galaxies: formation; intergalactic medium; large-scale structure of universe; methods: numerical  
  Abstract In models with dark matter made of particles with keV masses, such as a sterile neutrino, small-scale density perturbations are suppressed, delaying the period at which the lowest mass galaxies are formed and therefore shifting the reionization processes to later epochs. In this study, focusing on Warm Dark Matter (WDM) with masses close to its present lower bound, i.e., around the 3. keV region, we derive constraints from galaxy luminosity functions, the ionization history and the Gunn-Peterson effect. We show that even if star formation efficiency in the simulations is adjusted to match the observed UV galaxy luminosity functions in both CDM and WDM models, the full distribution of Gunn-Peterson optical depth retains the strong signature of delayed reionization in the WDM model. However, until the star formation and stellar feedback model used in modern galaxy formation simulations is constrained better, any conclusions on the nature of dark matter derived from reionization observables remain model-dependent.  
  Address (down) [Villanueva-Domingo, Pablo; Mena, Olga] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: gnedin@fnal.gov  
  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 0004-637x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000422865600009 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3455  
Permanent link to this record
 
 
Author Villanueva-Domingo, P.; Mena, O.; Palomares-Ruiz, S. url  doi
openurl 
  Title A Brief Review on Primordial Black Holes as Dark Matter Type Journal Article
  Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal Front. Astron. Space Sci.  
  Volume 8 Issue Pages 681084 - 10pp  
  Keywords primordial black holes; dark matter; cosmology; accretion; 21 cm cosmology; gravitational waves; cosmic microwave background; microlensing  
  Abstract Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.  
  Address (down) [Villanueva-Domingo, Pablo; Mena, Olga; Palomares-Ruiz, Sergio] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.villanueva.domingo@gmail.com  
  Corporate Author Thesis  
  Publisher Frontiers Media Sa Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2296-987x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000660081700001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4852  
Permanent link to this record
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