# TH Articles

2021-05-29
08:49
 Model independent analysis of the angular observables in $B^{0} \to K^{*0} \mu^+ \mu^-$ and $B^{+} \to K^{*+} \mu^+ \mu^-$ / Hurth, T. (U. Mainz, PRISMA) ; Mahmoudi, F. (IP2I, Lyon ; CERN) ; Neshatpour, S. (IP2I, Lyon) We analyse the results recently presented on the $B^{+} \to K^{*+} \mu^+ \mu^-$ angular observables by the LHCb Collaboration which show indications for New Physics beyond the Standard Model. Within a model-independent analysis, we compare the fit results with the corresponding results for the angular observables in $B^{0} \to K^{*0} \mu^+ \mu^-$.. arXiv:2012.12207; CERN-TH-2020-222; MITP-20-085.- 2021-05-19 - 4 p. - Published in : Phys. Rev. D 103 (2021) 095020 Article from SCOAP3: PDF;

2021-05-01
04:40
 Following in Tini’s Giant Footsteps / Ellis, John (King's Coll. London ; CERN ; NICPB, Tallinn) This paper describes my personal appreciation of some of Tini Veltman's great research achievements and how my own research career has followed the pathways he opened. Among the topics where he has been the most influential have been the pursuit and study of the Higgs boson and the calculation of radiative corrections that enabled the masses of the top quark and the Higgs boson to be predicted ahead of their discoveries. [...] arXiv:2104.14479; KCL-PH-TH/2021-27; CERN-TH-2021-067.- 2021 - 13 p. - Published in : Acta Phys. Pol. B 52 (2021) 561-574 Article from SCOAP3: PDF; In : Special volume of Acta Physica Polonica B commemorating Martinus Veltman, pp.561-574

2021-04-27
04:52
 Dark matter and the early Universe: a review / Arbey, A. (IP2I, Lyon ; CERN ; IUF, Paris) ; Mahmoudi, F. (IP2I, Lyon ; CERN ; IUF, Paris) Dark matter represents currently an outstanding problem in both cosmology and particle physics. In this review we discuss the possible explanations for dark matter and the experimental observables which can eventually lead to the discovery of dark matter and its nature, and demonstrate the close interplay between the cosmological properties of the early Universe and the observables used to constrain dark matter models in the context of new physics beyond the Standard Model.. arXiv:2104.11488; CERN-TH-2021-066.- 2021-07 - 41 p. - Published in : Prog. Part. Nucl. Phys. 119 (2021) 103865 Fulltext: PDF;

2021-04-22
11:42
 Non-abelian infrared divergences on the celestial sphere / Magnea, Lorenzo (CERN ; INFN, Turin ; Turin U.) We consider the infrared factorisation of non-abelian multi-particle scattering amplitudes, and we study the form of the universal colour operator responsible for infrared divergences, when expressed in terms of coordinates on the `celestial sphere' intersecting the future light-cone at asymptotic distances. We find that colour-dipole contributions to the infrared operator, to all orders in perturbation theory, have a remarkably simple expression in these coordinates, with scale and coupling dependence factorised from kinematics and colour. [...] arXiv:2104.10254; CERN-TH-2021-063.- 2021-05-31 - 23 p. - Published in : JHEP 2105 (2021) 282 Article from SCOAP3: PDF; Fulltext: PDF;

2021-04-15
05:11
 Precision calculation of dark radiation from spinning primordial black holes and early matter-dominated eras / Arbey, Alexandre (IP2I, Lyon ; CERN ; IUF, Paris) ; Auffinger, Jérémy (IP2I, Lyon) ; Sandick, Pearl (Utah U.) ; Shams Es Haghi, Barmak (Utah U.) ; Sinha, Kuver (Oklahoma U.) We present precision calculations of dark radiation in the form of gravitons coming from Hawking evaporation of spinning primordial black holes (PBHs) in the early Universe. Our calculation incorporates a careful treatment of extended spin distributions of a population of PBHs, the PBH reheating temperature, and the number of relativistic degrees of freedom. [...] arXiv:2104.04051; CERN-TH-2021-049.- 2021-06-15 - 18 p. - Published in : Phys. Rev. D 103 (2021) 123549 Fulltext from publisher: PDF;

2021-04-13
04:41
 Classical Gravity from Loop Amplitudes / Bjerrum-Bohr, N. Emil J. (Bohr Inst.) ; Damgaard, Poul H. (Bohr Inst. ; CERN) ; Planté, Ludovic (Unlisted, FR) ; Vanhove, Pierre (IPhT, Saclay ; Higher Sch. of Economics, Moscow ; CERN) We describe an efficient method for extracting the parts of $D$-dimensional loop integrals that are needed to derive observables in classical general relativity from scattering amplitudes. Our approach simplifies the soft-region method of integration by judiciously combining terms before the final integrations. [...] arXiv:2104.04510; IPhT-t21/015; CERN-TH-2021-052.- 2021-07-15 - 42 p. - Published in : Phys. Rev. D 104 (2021) 026009 Fulltext from publisher: PDF;

2021-04-09
04:00
 Consequences of chirally enhanced explanations of $(g-2)_\mu$ for $h\to \mu\mu$ and $Z\to \mu\mu$ / Crivellin, Andreas (CERN ; PSI, Villigen ; Zurich U.) ; Hoferichter, Martin (U. Bern, AEC) With the long-standing tension between experiment and Standard-Model (SM) prediction in the anomalous magnetic moment of the muon $a_\mu$ recently reaffirmed by the Fermilab experiment, the crucial question becomes which other observables could be sensitive to the underlying physics beyond the SM to which $a_\mu$ may be pointing. While from the effective field theory (EFT) point of view no direct correlations exist, this changes in specific new physics models. [...] arXiv:2104.03202; CERN-TH-2021-050; PSI-PR-21-04; ZU-TH 14/21.- 2021-04-07 - 19 p. - Published in : JHEP 2107 (2021) 135

2021-03-31
04:11
 Renormalization of the topological charge density in QCD with dimensional regularization / Lüscher, Martin (CERN ; U. Bern, AEC) ; Weisz, Peter (Munich, Max Planck Inst.) To all orders of perturbation theory, the renormalization of the topological charge density in dimensionally regularized QCD is shown to require no more than an additive renormalization proportional to the divergence of the flavour-singlet axial current. The proof is based on the standard BRS analysis of the QCD vertex functional in the background gauge and exploits the special algebraic properties of the charge density through the Stora--Zumino chain of descent equations.. arXiv:2103.15440; CERN-TH-2021-041; MPP-2021-38.- 2021 - 11 p. - Published in : Eur. Phys. J. C 81 (2021) 519 Article from SCOAP3: PDF; Fulltext: PDF;

2021-03-17
04:47
 Moduli-dependent KK towers and the swampland distance conjecture on the quintic Calabi-Yau manifold / Ashmore, Anthony (Chicago U. ; Chicago U., EFI ; Paris, LPTHE) ; Ruehle, Fabian (CERN ; Oxford U., Theor. Phys.) We use numerical methods to obtain moduli-dependent Calabi-Yau metrics and from them the moduli-dependent massive tower of Kaluza-Klein states for the one-parameter family of quintic Calabi-Yau manifolds. We then compute geodesic distances in their Kähler and complex structure moduli space using exact expressions from mirror symmetry, approximate expressions, and numerical methods and compare the results. [...] arXiv:2103.07472; CERN-TH-2021-032.- 2021-05-29 - 10 p. - Published in : Phys. Rev. D 103 (2021) 106028 Article from SCOAP3: PDF; Fulltext: PDF;

2021-03-02
04:32
 Leading-Color Two-Loop QCD Corrections for Three-Jet Production at Hadron Colliders / Abreu, S. (CERN ; UCLA) ; Cordero, F. Febres (Florida State U.) ; Ita, H. (Freiburg U.) ; Page, B. (LPENS, Paris) ; Sotnikov, V. (Munich, Max Planck Inst.) We present the complete set of leading-color two-loop contributions required to obtain next-to-next-to-leading-order (NNLO) QCD corrections to three-jet production at hadron colliders. We obtain analytic expressions for a generating set of finite remainders, valid in the physical region for three-jet production. [...] arXiv:2102.13609; CERN-TH-2021-023; FR-PHENO-2021-06; MPP-2021-20.- 2021-07-15 - 25 p. - Published in : JHEP 2107 (2021) 095 Fulltext: PDF;