# 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; Fulltext: PDF;

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 - 28 p. - Published in : JHEP 2105 (2021) 282 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;

2021-02-25
04:20
 Semi-automated BSM model building procedures in MARTY-1.1 through a 2HDM example / Uhlrich, G. (IP2I, Lyon) ; Mahmoudi, F. (IP2I, Lyon ; CERN) ; Arbey, A. (IP2I, Lyon ; CERN ; IUF, Paris) MARTY is a C++ computer algebra system specialized for High Energy Physics that can calculate amplitudes, squared amplitudes and Wilson coefficients in a large variety of beyond the Standard Model scenarios up to the one-loop order. It is fully independent of any other framework and its main development guideline is generality, in order to be adapted easily to any type of model. [...] arXiv:2102.11551; CERN-TH-2021-025.- SISSA, 2021-05-10 - 14 p. - Published in : PoS TOOLS2020 (2020) 042 Fulltext: 2102.11551 - PDF; PoS(TOOLS2020)042 - PDF; In : Tools for High Energy Physics and Cosmology, Lyon, France, 2 - 6 Nov 2020, pp.042

2021-01-20
04:01
 Black hole quasinormal modes and isospectrality in Deser-Woodard nonlocal gravity / Chen, Che-Yu (Taiwan, Inst. Phys.) ; Park, Sohyun (CERN) We investigate the gravitational perturbations of the Schwarzschild black hole in the nonlocal gravity model recently proposed by Deser and Woodard (DW-II). The analysis is performed in the localized version in which the nonlocal corrections are represented by some auxiliary scalar fields. [...] arXiv:2101.06600; CERN-TH-2021-011.- 2021-03-19 - 10 p. - Published in : Phys. Rev. D 103 (2021) 064029 Fulltext: PDF; Fulltext from Publisher: PDF; Fulltext from publisher: PDF;

2021-01-16
04:01
 Radiation Reaction from Soft Theorems / Di Vecchia, Paolo (Bohr Inst. ; Nordita ; Royal Inst. Tech., Stockholm) ; Heissenberg, Carlo (Nordita ; Royal Inst. Tech., Stockholm ; Uppsala U.) ; Russo, Rodolfo (Queen Mary, U. of London) ; Veneziano, Gabriele (CERN ; College de France) Radiation reaction (RR) terms at the third post-Minkowskian (3PM) order have recently been found to be instrumental in restoring smooth continuity between the non-relativistic, relativistic, and ultra-relativistic (including the massless) regimes. Here we propose a new and intriguing connection between RR and soft (bremsstrahlung) theorems which short-circuits the more involved conventional loop computations. [...] arXiv:2101.05772; CERN-TH-2021-008; NORDITA 2021-001; QMUL-PH-21-03; UUITP-03/21.- 2021-07-10 - 17 p. - Published in : Phys. Lett. B 818 (2021) 136379 Article from SCOAP3: PDF; Fulltext: PDF;

2021-01-15
04:01
 Axion assisted Schwinger effect / Domcke, Valerie (CERN ; EPFL, Lausanne, LPPC) ; Ema, Yohei (DESY) ; Mukaida, Kyohei (CERN) We point out an enhancement of the pair production rate of charged fermions in a strong electric field in the presence of time dependent classical axion-like background field, which we call axion assisted Schwinger effect. While the standard Schwinger production rate is proportional to $\exp(-\pi(m^2+p_T^2 )/E)$, with $m$ and $p_T$ denoting the fermion mass and its momentum transverse to the electric field $E$, the axion assisted Schwinger effect can be enhanced at large momenta to $\exp(-\pi m^2/E)$. [...] arXiv:2101.05192; DESY-21-006; CERN-TH-2021-010.- 2021-05-03 - 18 p. - Published in : JHEP 2105 (2021) 001 Article from SCOAP3: PDF; Fulltext: PDF; Fulltext from publisher: PDF;

2021-01-15
04:01
 The Schwarzian sector of higher spin CFTs / Datta, Shouvik (CERN) Two-dimensional conformal field theories with Virasoro symmetry generically contain a Schwarzian sector. This sector is related to the near-horizon region of the near-extremal BTZ black hole in the holographic dual. [...] arXiv:2101.04980; CERN-TH-2021-009.- 2021-04-19 - 22 p. - Published in : JHEP 2104 (2021) 171 Article from SCOAP3: PDF; Fulltext: PDF;

2021-01-12
04:25
 Hawking radiation by spherically-symmetric static black holes for all spins: Teukolsky equations and potentials / Arbey, Alexandre (IP2I, Lyon ; CERN ; IUF, Paris) ; Auffinger, Jérémy (IP2I, Lyon) ; Geiller, Marc (Lyon, Ecole Normale Superieure) ; Livine, Etera R. (Lyon, Ecole Normale Superieure) ; Sartini, Francesco (Lyon, Ecole Normale Superieure) In the context of the dynamics and stability of black holes in modified theories of gravity, we derive the Teukolsky equations for massless fields of all spins in general spherically-symmetric and static metrics. We then compute the short-ranged potentials associated with the radial dynamics of spin 1 and spin 1/2 fields, thereby completing the existing literature on spin 0 and 2. [...] arXiv:2101.02951; CERN-TH-2021-007.- 2021-05-08 - 17 p. - Published in : Phys. Rev. D 103 (2021) 104010 Fulltext: PDF; Fulltext from Publisher: PDF; Fulltext from publisher: PDF;