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(419) Production(s) de l'année 2017
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Monojet searches for momentum-dependent dark matter interactions
Auteur(s): Barducci D., Bharucha Aoife
(Article) Publié:
Journal Of High Energy Physics, vol. 01 p.078 (2017)
Texte intégral en Openaccess :
Ref HAL: in2p3-01372979_v1
Ref Arxiv: 1609.07490
DOI: 10.1007/JHEP01(2017)078
WoS: 000397643300001
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
10 Citations
Résumé: We consider minimal dark matter scenarios featuring momentum-dependent couplings of the dark sector to the Standard Model. We derive constraints from existing LHC searches in the monojet channel, estimate the future LHC sensitivity for an integrated luminosity of 300 fb$^{-1}$, and compare with models exhibiting conventional momentum-independent interactions with the dark sector. In addition to being well motivated by (composite) pseudo-Goldstone dark matter scenarios, momentum-dependent couplings are interesting as they weaken direct detection constraints. For a specific dark matter mass, the LHC turns out to be sensitive to smaller signal cross-sections in the momentum-dependent case, by virtue of the harder jet transverse-momentum distribution.
Commentaires: 23 pages, 4 figures
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Multiple D3-instantons and mock modular forms I
Auteur(s): Alexandrov S., Banerjee S., Manschot Jan, Pioline Boris
(Article) Publié:
Communications In Mathematical Physics, vol. 353 p.379-411 (2017)
Texte intégral en Openaccess :
Ref HAL: cea-01318414_v1
Ref Arxiv: 1605.05945
DOI: 10.1007/s00220
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
Résumé: We study D3-instanton corrections to the hypermultiplet moduli space in type IIB string theory compactified on a Calabi-Yau threefold. In a previous work, consistency of D3-instantons with S-duality was established at first order in the instanton expansion, using the modular properties of the M5-brane elliptic genus. We extend this analysis to the two-instanton level, where wall-crossing phenomena start playing a role. We focus on the contact potential, an analogue of the Kähler potential which must transform as a modular form under S-duality. We show that it can be expressed in terms of a suitable modification of the partition function of D4-D2-D0 BPS black holes, constructed out of the generating function of MSW invariants (the latter coincide with Donaldson-Thomas invariants in a particular chamber). Modular invariance of the contact potential then requires that, in case where the D3-brane wraps a reducible divisor, the generating function of MSW invariants must transform as a vector-valued mock modular form, with a specific modular completion built from the MSW invariants of the constituents. Physically, this gives a powerful constraint on the degeneracies of BPS black holes. Mathematically, our result gives a universal prediction for the modular properties of Donaldson-Thomas invariants of pure two-dimensional sheaves.
Commentaires: 33 pages
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Homogenization near resonances and artificial magnetism in 3D dielectric metamaterials
Auteur(s): Bouchitté Guy, Bourel Christophe, Felbacq D.
(Article) Publié:
Archive For Rational Mechanics And Analysis, vol. 225 p.1233-1277 (2017)
Texte intégral en Openaccess :
Ref HAL: hal-01240316_v1
Ref Arxiv: 1512.02463
DOI: 10.1007/s00205-017-1132-1
WoS: 000404633500008
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
17 Citations
Résumé: It is now well established that the homogenization of a periodic array of parallel dielectric fibers with suitably scaled high permittivity can lead to a (possibly) negative frequency-dependent effective permeability. However this result based on a two-dimensional approach holds merely in the case of linearly polarized magnetic fields, reducing thus its applications to infinite cylindrical obstacles. In this paper we consider a dielectric structure placed in a bounded domain of $\mathbb{R}^3$ and perform a full 3D asymptotic analysis. The main ingredient is a new averaging method for characterizing the bulk effective magnetic field in the vanishing-period limit. We evidence a vectorial spectral problem on the periodic cell which determines micro-resonances and encodes the oscillating behavior of the magnetic field from which artificial magnetism arises. At a macroscopic level we deduce an effective permeability tensor that we can be make explicit as a function of the frequency. As far as sign-changing permeability are sought after, we may foresee that periodic bulk dielectric inclusions could be an efficient alternative to the very popular metallic split-ring structure proposed by Pendry.
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A New Braid-like Algebra for Baxterisation
Auteur(s): Crampé N., Frappat L., Ragoucy E., Vanicat M.
(Article) Publié:
Communications In Mathematical Physics, vol. 349 p.271-283 (2017)
Texte intégral en Openaccess :
Ref HAL: hal-01220002_v1
Ref Arxiv: 1509.05516
DOI: 10.1007/s00220-016-2780-y
WoS: WOS:000392061000005
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
3 Citations
Résumé: We introduce a new Baxterisation for R-matrices that depend separately on twospectral parameters. The Baxterisation is based on a new algebra, close to butdifferent from the braid group. This allows us to recover the R-matrix of themulti-species generalization of the totally asymmetric simple exclusion processwith different hopping rates.
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Ray chaos in a photonic crystal
Auteur(s): Rousseau E., Felbacq D.
(Article) Publié:
Europhysics Letters (Epl), vol. 117 p.14002 (2017)
Texte intégral en Openaccess :
Ref HAL: hal-01095319_v3
DOI: 10.1209/0295-5075/117/14002
WoS: WOS:000397026200018
Exporter : BibTex | endNote
2 Citations
Résumé: The ray dynamics in a photonic crystal was investigated. Chaos occurs for perfectly periodic crystals, the rays dynamics being very sensitive to the initial conditions. Depending on the filling factor, the ray dynamics can exhibit stable paths near (fully) chaotic motion. The degree of chaoticity is quantified through the computation of Lyapunov exponents. As a result, the more diluted is the geometry, the more chaotic is the dynamic. Therefore, despite the perfect periodicity of the geometry, light transport is a diffusive process which can be tuned from normal diffusion (brownian motion) to anomalous diffusion because of the existence of L ́evy flights.
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Global Jacquet-Langlands Correspondence for Division Algebras in Characteristic $p$
Auteur(s): Badulescu Alexandru Ioan, Roche P.
(Article) Publié:
International Mathematics Research Notices, vol. 7 p.2172–2206 (2017)
Texte intégral en Openaccess :
Ref HAL: hal-02067734_v1
DOI: 10.1093/imrn/rnw094
WoS: 000404041400007
Exporter : BibTex | endNote
6 Citations
Résumé: We prove a full global Jacquet-Langlands correspondence between GL(n) and division algebras over global fields of non zero characteristic. If D is a central division algebra of dimension n 2 over a global field F of non zero characteristic , we prove that there exists an injective map from the set of automorphic representations of D × to the set of automorphic square integrable representations of GL n (F), compatible at all places with the local Jacquet-Langlands correspondence for unitary representations. We characterize the image of the map. As a consequence we get multiplicity one and strong multiplicity one theorems for D × .
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