# TH Articles

Ultimi arrivi:
2017-04-13
08:29
 Single top polarisation as a window to new physics / Aguilar-Saavedra, J.A. (Granada U., Theor. Phys. Astrophys.) ; Degrande, C. (CERN) ; Khatibi, S. (IPM, Tehran) We discuss the effect of heavy new physics, parameterised in terms of four-fermion operators, in the polarisation of single top (anti-)quarks in the $t$-channel process at the LHC. It is found that for operators involving a right-handed top quark field the relative effect on the longitudinal polarisation is twice larger than the relative effect on the total cross section. [...] CERN-TH-2017-013; arXiv:1701.05900.- 2017 - 9 p. - Published in : 10.1016/j.physletb.2017.04.023 Article from SCOAP3: PDF; Elsevier Open Access article: PDF; Fulltext: PDF;

2017-03-30
07:23
 Inflationary Perturbations in No-Scale Theories / Salvio, Alberto (CERN) We study the inflationary perturbations in general (classically) scale-invariant theories. Such scenario is motivated by the hierarchy problem and provides natural inflationary potentials and dark matter candidates. [...] CERN-TH-2017-068; arXiv:1703.08012.- 2017-03-23 - 38 p. - Published in : Eur.Phys.J. C77 (2017) 267 Fulltext: PDF;

2017-03-14
16:44
 SMD-based numerical stochastic perturbation theory / Dalla Brida, Mattia (Milan Bicocca U. ; INFN, Milan Bicocca) ; Lüscher, Martin (CERN ; Bern U.) The viability of a variant of numerical stochastic perturbation theory, where the Langevin equation is replaced by the SMD algorithm, is examined. In particular, the convergence of the process to a unique stationary state is rigorously established and the use of higher-order symplectic integration schemes is shown to be highly profitable in this context. [...] CERN-TH-2017-057; arXiv:1703.04396.- 2017 - 35 p. - Published in : Eur. Phys. J. C 77 (2017) 308 Fulltext: PDF;

2017-03-14
16:44
 Dispersion relation for hadronic light-by-light scattering: two-pion contributions / Colangelo, Gilberto (Bern U. ; U. Bern, AEC) ; Hoferichter, Martin (Washington U., Seattle ; Santa Barbara, KITP) ; Procura, Massimiliano (CERN) ; Stoffer, Peter (Bonn U., HISKP ; U. Bonn, Phys. Inst., BCTP ; UC, San Diego) In this third paper of a series dedicated to a dispersive treatment of the hadronic light-by-light (HLbL) tensor, we derive a partial-wave formulation for two-pion intermediate states in the HLbL contribution to the anomalous magnetic moment of the muon $(g-2)_\mu$, including a detailed discussion of the unitarity relation for arbitrary partial waves. We show that obtaining a final expression free from unphysical helicity partial waves is a subtle issue, which we thoroughly clarify. [...] INT-PUB-17-009; CERN-TH-2017-041; NSF-KITP-17-036; arXiv:1702.07347.- 2017 - 70 p. - Published in : J. High Energy Phys. 04 (2017) 161 Fulltext: PDF; Springer Open Access article: PDF;

2017-03-14
16:44
 Thermodynamics of strongly-coupled lattice QCD in the chiral limit / de Forcrand, Philippe (Zurich, ETH ; CERN) ; Romatschke, Paul (Colorado U.) ; Unger, Wolfgang (Bielefeld U.) ; Vairinhos, Helvio (Zurich, ETH) In the strong coupling limit, $n$-point functions in lattice QCD with staggered fermions can be rewritten exactly as sums over constrained configurations of monomers, dimers, and baryon loops covering the spacetime lattice. Worm algorithms provide efficient global sampling methods over such ensembles, and are particularly efficient in the chiral limit. [...] arXiv:1701.08324; CERN-TH-2017-012.- 2017 - 7 p. - Published in : PoS: LATTICE2016 (2017) , pp. 086 Fulltext: PDF; Published version from PoS: PDF; In : 34th International Symposium on Lattice Field Theory, Southampton, UK, 24 - 30 Jul 2016, pp.086

2017-03-10
11:05
 Testing Lorentz invariance of dark matter with satellite galaxies / Bettoni, Dario (U. Heidelberg, ITP) ; Nusser, Adi (Technion) ; Blas, Diego (CERN) ; Sibiryakov, Sergey (CERN ; EPFL, Lausanne, LPPC ; Moscow, INR) We develop the framework for testing Lorentz invariance in the dark matter sector using galactic dynamics. We consider a Lorentz violating (LV) vector field acting on the dark matter component of a satellite galaxy orbiting in a host halo. [...] CERN-TH-2017-037; INR-TH-2017-003; arXiv:1702.07726.- 2017 - 20 p. - Published in : J. Cosmol. Astropart. Phys. 05 (2017) 024 Fulltext: PDF;

2017-02-16
07:58
 QED Corrections to Hadronic Observables / Patella, Agostino (CERN ; Plymouth U., Math. Stat. Dept.) When aiming at the percent precision in hadronic quantities calculated by means of lattice simulations, isospin breaking effects become relevant. These are of two kinds: up/down mass splitting and electromagnetic corrections. [...] CERN-TH-2017-019; arXiv:1702.03857.- 2017-02-13 - 31 p. - Published in : PoS: LATTICE2016, pp. 020 Fulltext: arXiv:1702.03857 - PDF; PoS(LATTICE2016)020 - PDF; LATTICE2016_020 - PDF; In : 34th International Symposium on Lattice Field Theory, Southampton, UK, 24 - 30 Jul 2016, pp.020

2017-02-10
07:37
 Aspects of Berry phase in QFT / Baggio, Marco (Leuven U.) ; Niarchos, Vasilis (Durham U., Dept. of Math. ; Durham U., CPT) ; Papadodimas, Kyriakos (CERN ; U. Groningen, VSI) When continuous parameters in a QFT are varied adiabatically, quantum states typically undergo mixing---a phenomenon characterized by the Berry phase. We initiate a systematic analysis of the Berry phase in QFT using standard quantum mechanics methods. [...] CERN-TH-2016-241; DCPT-16-55; arXiv:1701.05587.- 2017 - 50 p. - Published in : J. High Energy Phys. 04 (2017) 062 Fulltext: PDF; Springer Open Access article: PDF;

2017-02-09
08:13
 Nested soft-collinear subtractions in NNLO QCD computations / Caola, Fabrizio (CERN ; Durham U., IPPP) ; Melnikov, Kirill (Karlsruhe U.) ; Röntsch, Raoul (Karlsruhe U.) We discuss a modification of the next-to-next-to-leading order (NNLO) subtraction scheme based on the residue-improved sector decomposition that reduces the number of double-real emission sectors from five to four. In particular, a sector where energies and angles of unresolved particles vanish in a correlated fashion is redundant and can be discarded. [...] CERN-TH-2017-029; IPPP-17-10; TTP17-003; arXiv:1702.01352.- 2017 - 64 p. - Published in : Eur. Phys. J. C 77 (2017) 248 Fulltext: PDF; Springer Open Access article: PDF;

2017-02-09
08:13
 Cosmological Implications of Dark Matter Bound States / Mitridate, Andrea (Pisa, Scuola Normale Superiore) ; Redi, Michele (INFN, Florence ; Florence U.) ; Smirnov, Juri (INFN, Florence ; Florence U.) ; Strumia, Alessandro (Pisa U. ; INFN, Pisa ; CERN) We present generic formulae for computing how Sommerfeld corrections together with bound-state formation affects the thermal abundance of Dark Matter with non-abelian gauge interactions. We consider DM as a fermion 3plet (wino) or 5plet under SU(2)$_L$. [...] CERN-TH-2017-030; arXiv:1702.01141; IFUP-TH-2017.- 2017-02-03 - 39 p. - Published in : JCAP 1705 (2017) 006 Fulltext: PDF;