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Author Binosi, D.; Ibañez, D.; Papavassiliou, J. url  doi
openurl 
  Title Nonperturbative study of the four gluon vertex Type Journal Article
  Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 09 Issue 9 Pages 059 - 32pp  
  Keywords Nonperturbative Effects; QCD; Confinement  
  Abstract In this paper we study the nonperturbative structure of the SU(3) four-gluon vertex in the Landau gauge, concentrating on contributions quadratic in the metric. We employ an approximation scheme where “one-loop” diagrams are computed using fully dressed gluon and ghost propagators, and tree-level vertices. When a suitable kinematical configuration depending on a single momentum scale p is chosen, only two structures emerge: the tree-level four-gluon vertex, and a tensor orthogonal to it. A detailed numerical analysis reveals that the form factor associated with this latter tensor displays a change of sign (zero-crossing) in the deep infrared, and finally diverges logarithmically. The origin of this characteristic behavior is proven to be entirely due to the masslessness of the ghost propagators forming the corresponding ghost-loop diagram, in close analogy to a similar effect established for the three-gluon vertex. However, in the case at hand, and under the approximations employed, this particular divergence does not affect the form factor proportional to the tree-level tensor, which remains finite in the entire range of momenta, and deviates moderately from its naive tree-level value. It turns out that the kinematic configuration chosen is ideal for carrying out lattice simulations, because it eliminates from the connected Green's function all one-particle reducible contributions, projecting out the genuine one-particle irreducible vertex. Motivated by this possibility, we discuss in detail how a hypothetical lattice measurement of this quantity would compare to the results presented here, and the potential interference from an additional tensorial structure, allowed by Bose symmetry, but not encountered within our scheme.  
  Address [Binosi, D.; Ibanez, D.] European Ctr Theoret Studies Nucl Phys & Related, I-38123 Villazzano, TN, Italy, Email: binosi@ectstar.eu;  
  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:000342215400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 1954  
Permanent link to this record
 

 
Author Ghosh, P.; Lopez-Fogliani, D.E.; Mitsou, V.A.; Muñoz, C.; Ruiz de Austri, R. url  doi
openurl 
  Title Probing the μnu SSM with light scalars, pseudoscalars and neutralinos from the decay of a SM-like Higgs boson at the LHC Type Journal Article
  Year 2014 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 11 Issue 11 Pages 102 - 57pp  
  Keywords Supersymmetry Phenomenology  
  Abstract The “mu from nu” supersymmetric standard model (mu nu SSM) can accommodate the newly discovered Higgs-like scalar boson with a mass around 125GeV. This model provides a solution to the mu-problem and simultaneously reproduces correct neutrino physics by the simple use of right-handed neutrino superfields. These new superfields together with the introduced R-parity violation can produce novel and characteristic signatures of the μnu SSM at the LHC. We explore the signatures produced through two-body Higgs decays into the new states, provided that these states lie below in the mass spectrum. For example, a pair produced light neutralinos depending on the associated decay length can give rise to displaced multi-leptons/taus/jets/photons with small/moderate missing transverse energy. In the same spirit, a Higgs-like scalar decaying to a pair of scalars/pseudoscalars can produce final states with prompt multi-leptons/taus/jets/photons.  
  Address [Ghosh, Pradipta; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: pradipta.ghosh@uam.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 1029-8479 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000345590600002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2016  
Permanent link to this record
 

 
Author Barenboim, G.; Bosch, C.; Lee, J.S.; Lopez-Ibañez, M.L.; Vives, O. url  doi
openurl 
  Title Flavor-changing Higgs boson decays into bottom and strange quarks in supersymmetric models Type Journal Article
  Year 2015 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 92 Issue 9 Pages 095017 - 15pp  
  Keywords  
  Abstract In this work, we explore the flavor-changing decays H-i -> bs in a general supersymmetric scenario. In these models the flavor-changing decays arise at loop level, but-because they originate from a dimension-four operator-they do not decouple and may provide a first sign of new physics for heavy masses beyond the reach of colliders. In the framework of the minimal supersymmetric extension of the Standard Model, we find that the largest branching ratio of the lightest Higgs (H-1) is O(10(-6)) after imposing present experimental constraints, while heavy Higgs states may still present branching ratios O(10(-3)). In a more general supersymmetric scenario, where additional Higgs states may modify the Higgs mixings, the branching ratio BR(H-1 -> bs) can reach values O(10(-4)), while heavy Higgses still remain at O(10(-3)). Although these values are clearly out of reach for the LHC, a full study in a linear collider environment could be worth pursuing.  
  Address [Barenboim, G.; Bosch, C.; Lopez-Ibanez, M. L.; Vives, O.] Univ Valencia, Dept Fis Teor, CSIC, E-46100 Burjassot, Spain, Email: Gabriela.Barenboim@uv.es;  
  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:000364411600009 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2449  
Permanent link to this record
 

 
Author Choi, K.Y.; Lopez-Fogliani, D.E.; Muñoz, C.; Ruiz de Austri, R. url  doi
openurl 
  Title Gamma-ray detection from gravitino dark matter decay in the μnu SSM Type Journal Article
  Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 03 Issue 3 Pages 028 - 14pp  
  Keywords dark matter theory; supersymmetry and cosmology; gamma ray experiments  
  Abstract The μnu SSM provides a solution to the mu-problem of the MSSM and explains the origin of neutrino masses by simply using right-handed neutrino superfields. Given that R-parity is broken in this model, the gravitino is a natural candidate for dark matter since its lifetime becomes much longer than the age of the Universe. We consider the implications of gravitino dark matter in the μnu SSM, analyzing in particular the prospects for detecting gamma rays from decaying gravitinos. If the gravitino explains the whole dark matter component, a gravitino mass larger than 20 GeV is disfavored by the isotropic diffuse photon background measurements. On the other hand, a gravitino with a mass range between 0.1 – 20 GeV gives rise to a signal that might be observed by the FERMI satellite. In this way important regions of the parameter space of the μnu SSM can be checked.  
  Address [Choi, Ki-Young; Munoz, Carlos] Univ Autonoma Madrid, Dept Fis Teor, E-28049 Madrid, Spain, Email: kiyoung.choi@pusan.ac.kr  
  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:000276103000006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 464  
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Author Bertone, G.; Cerdeño, D.G.; Fornasa, M.; Ruiz de Austri, R.; Trotta, R. url  doi
openurl 
  Title Identification of dark matter particles with LHC and direct detection data Type Journal Article
  Year 2010 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 82 Issue 5 Pages 055008 - 7pp  
  Keywords  
  Abstract Dark matter (DM) is currently searched for with a variety of detection strategies. Accelerator searches are particularly promising, but even if weakly interacting massive particles are found at the Large Hadron Collider (LHC), it will be difficult to prove that they constitute the bulk of the DM in the Universe Omega(DM). We show that a significantly better reconstruction of the DM properties can be obtained with a combined analysis of LHC and direct detection data, by making a simple Ansatz on the weakly interacting massive particles local density rho(0)((chi) over bar1), i.e., by assuming that the local density scales with the cosmological relic abundance, (rho(0)((chi) over bar1)/rho(DM)) = (Omega(0)((chi) over bar1)/Omega(DM)). We demonstrate this method in an explicit example in the context of a 24-parameter supersymmetric model, with a neutralino lightest supersymmetric particle in the stau coannihilation region. Our results show that future ton-scale direct detection experiments will allow to break degeneracies in the supersymmetric parameter space and achieve a significantly better reconstruction of the neutralino composition and its relic density than with LHC data alone.  
  Address [Bertone, G.] Univ Zurich, Inst Theoret Phys, CH-8057 Zurich, 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 1550-7998 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000281741400005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ elepoucu @ Serial 380  
Permanent link to this record
 

 
Author ANTARES Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Hernandez-Rey, J.J.; Lambard, G.; Mangano, S.; Sanchez-Losa, A.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Optical and X-ray early follow-up of ANTARES neutrino alerts Type Journal Article
  Year 2016 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 02 Issue 2 Pages 062 - 29pp  
  Keywords gamma ray burst experiments; neutrino astronomy; X-ray telescopes  
  Abstract High-energy neutrinos could be produced in the interaction of charged cosmic rays with matter or radiation surrounding astrophysical sources. Even with the recent detection of extraterrestrial high-energy neutrinos by the IceCube experiment, no astrophysical neutrino source has yet been discovered. Transient sources, such as gamma-ray bursts, core-collapse supernovae, or active galactic nuclei are promising candidates. Multi-messenger programs offer a unique opportunity to detect these transient sources. By combining the information provided by the ANTARES neutrino telescope with information coming from other observatories, the probability of detecting a source is enhanced, allowing the possibility of identifying a neutrino progenitor from a single detected event. A method based on optical and X-ray follow-ups of high-energy neutrino alerts has been developed within the ANTARES collaboration. This method does not require any assumptions on the relation between neutrino and photon spectra other than time-correlation. This program, denoted as TAToO, triggers a network of robotic optical telescopes (TAROT and ROTSE) and the Swift-XRT with a delay of only a few seconds after a neutrino detection, and is therefore well-suited to search for fast transient sources. To identify an optical or Xray counterpart to a neutrino signal, the images provided by the follow-up observations are analysed with dedicated pipelines. A total of 42 alerts with optical and 7 alerts with Xray images taken with a maximum delay of 24 hours after the neutrino trigger have been analysed. No optical or X-ray counterparts associated to the neutrino triggers have been found, and upper limits on transient source magnitudes have been derived. The probability to reject the gamma-ray burst origin hypothesis has been computed for each alert.  
  Address [Adrian-Martinez, S.; Ardid, M.; Bou-Cabo, M.; Feis, I.; Herrero, A.; Martinez-Mora, J. A.; Saldana, M.] Univ Politecn Valencia, Inst Invest Gestio Integrada Zones Costaneres IGI, C Paranimf 1, Gandia 46730, Spain, Email: dornic@cppm.in2p3.fr;  
  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:000372467600063 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2588  
Permanent link to this record
 

 
Author Holz, S.; Plenter, J.; Xiao, C.W.; Dato, T.; Hanhart, C.; Kubis, B.; Meissner, U.G.; Wirzba, A. url  doi
openurl 
  Title Towards an improved understanding of eta -> gamma*gamma * Type Journal Article
  Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 81 Issue 11 Pages 1002 - 15pp  
  Keywords  
  Abstract We argue that high-quality data on the reaction e(+)e(-) -> pi(+) pi(-) eta will allow one to determine the doubly-virtual form factor eta -> gamma*gamma* in a model-independent way with controlled accuracy. This is an important step towards a reliable evaluation of the hadronic light-by-light scattering contribution to the anomalous magnetic moment of themuon. When analyzing the existing data for e(+) e(-) -> pi(+) pi(-) eta for total energies squared k(2) > 1GeV(2), we demonstrate that the effect of the a(2) meson provides a natural breaking mechanism for the commonly employed factorization ansatz in the doubly-virtual form factor F-eta gamma*gamma* (q(2), k(2)). However, better data are needed to draw firm conclusions.  
  Address [Holz, S.; Plenter, J.; Dato, T.; Kubis, B.; Meissner, U-G] Univ Bonn, Helmholtz Inst Strahlen & Kemphys Theorie, D-53115 Bonn, Germany, Email: holz@hiskp.uni-bonn.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 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000718113500001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5024  
Permanent link to this record
 

 
Author ANTARES Collaboration (Adrian-Martinez, S. et al); Barrios-Marti, J.; Hernandez-Rey, J.J.; Sanchez-Losa, A.; Tönnis, C.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Murchison Widefield Array Limits on Radio Emission from ANTARES Neutrino Events Type Journal Article
  Year 2016 Publication Astrophysical Journal Letters Abbreviated Journal Astrophys. J. Lett.  
  Volume 820 Issue 2 Pages L24 - 7pp  
  Keywords neutrinos; radio continuum: general  
  Abstract We present a search, using the Murchison Widefield Array (MWA), for electromagnetic (EM) counterparts to two candidate high-energy neutrino events detected by the ANTARES neutrino telescope in 2013 November and 2014 March. These events were selected by ANTARES because they are consistent, within 0 degrees.4, with the locations of galaxies within 20 Mpc of Earth. Using MWA archival data at frequencies between 118 and 182 MHz, taken similar to 20. days prior to, at the same time as, and up to a year after the neutrino triggers, we look for transient or strongly variable radio sources that are consistent with the neutrino positions. No such counterparts are detected, and we set a 5 sigma upper limit for low-frequency radio emission of similar to 10(37) erg s(-1) for progenitors at 20 Mpc. If the neutrino sources are instead not in nearby galaxies, but originate in binary neutron star coalescences, our limits place the progenitors at z greater than or similar to 0.2. While it is possible, due to the high background from atmospheric neutrinos, that neither event is astrophysical, the MWA observations are nevertheless among the first to follow up neutrino candidates in the radio, and illustrate the promise of wide-field instruments like MWA for detecting EM counterparts to such events.  
  Address [Croft, S.; Zheng, W.] Univ Calif Berkeley, Dept Astron, 501 Campbell Hall 3411, Berkeley, CA 94720 USA  
  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 2041-8205 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000373085300002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 2613  
Permanent link to this record
 

 
Author Faleiro, R.; Pavao, R.; Costa, H.A.S.; Hiller, B.; Blin, A.H.; Sampaio, M. url  doi
openurl 
  Title Perturbative approach to entanglement generation in QFT using the S matrix Type Journal Article
  Year 2020 Publication Journal of Physics A Abbreviated Journal J. Phys. A  
  Volume 53 Issue 36 Pages 365301 - 19pp  
  Keywords S-matrix; entanglement; QFT; cross-section  
  Abstract We compute the variation of the von Neumann (VN) entropy Delta Sbetween the asymptoticinandoutmomenta modes of a real scalar field A, when elastically scattered against the modes of another scalar field B. This is done to see how the entanglement between the two fields' momenta changes under the scattering procedure. The calculation is separated into two case studies, one where the fields' asymptoticinstates are separable, and another where they are arbitrarily entangled. We perform a perturbative calculation to one loop order in the separable case, and verify that Delta Schanges in a non-trivial way when we vary the momentum of the incoming field modes and/or the coupling of the theory. Finally, also in the separable case, we show an explicit dependence between Delta Sand the cross-section of the collision, consistent with perturbation theory.  
  Address [Faleiro, Ricardo; Hiller, Brigitte] Univ Lisbon, Dept Math, Ave Rovisco Pais, P-1049001 Lisbon, Portugal, Email: ricardofaleiro@tecnico.ulisboa.pt  
  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 1751-8113 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000563486000001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4511  
Permanent link to this record
 

 
Author Begone, G.; Deisenroth, M.P.; Kim, J.S.; Liem, S.; Ruiz de Austri, R.; Welling, M. url  doi
openurl 
  Title Accelerating the BSM interpretation of LHC data with machine learning Type Journal Article
  Year 2019 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe  
  Volume 24 Issue Pages 100293 - 5pp  
  Keywords  
  Abstract The interpretation of Large Hadron Collider (LHC) data in the framework of Beyond the Standard Model (BSM) theories is hampered by the need to run computationally expensive event generators and detector simulators. Performing statistically convergent scans of high-dimensional BSM theories is consequently challenging, and in practice unfeasible for very high-dimensional BSM theories. We present here a new machine learning method that accelerates the interpretation of LHC data, by learning the relationship between BSM theory parameters and data. As a proof-of-concept, we demonstrate that this technique accurately predicts natural SUSY signal events in two signal regions at the High Luminosity LHC, up to four orders of magnitude faster than standard techniques. The new approach makes it possible to rapidly and accurately reconstruct the theory parameters of complex BSM theories, should an excess in the data be discovered at the LHC.  
  Address [Begone, Gianfranco; Liem, Sebastian] Univ Amsterdam, GRAPPA, Sci Pk 904, NL-1098 XH Amsterdam, Netherlands, Email: jongsoo.kim@tu-dortmund.de  
  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 2212-6864 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000465292500018 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3994  
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