Publications

Order by: publication date number of citations

• Precise predictions for boosted Higgs production

  Kathrin Becker, Fabrizio Caola, Andrea Massironi, Bernhard Mistlberger, Pier F. Monni, Xuan Chen, Stefano Frixione, Thomas Gehrmann, Nigel Glover, Keith Hamilton, Alexander Huss, Stephen P. Jones, Alexander Karlberg, Matthias Kerner, Kirill Kudashkin, Jonas M. Lindert, Gionata Luisoni, Michelangelo L. Mangano, Stefano Pozzorini, Emanuele Re, Gavin P. Salam, Eleni Vryonidou, Christopher Wever

  SciPost Phys. Core 7, 001 (2024) · published 4 January 2024 | Toggle abstract · pdf

  Inclusive Higgs boson production at large transverse momentum is induced by different production channels. We focus on the leading production mechanism through gluon fusion, and perform a consistent combination of the state of the art calculations obtained in the infinite-top-mass effective theory at next-to-next-to-leading order (NNLO) and in the full Standard Model (SM) at next-to-leading order (NLO). We thus present approximate QCD predictions for this process at NNLO, and a study of the corresponding perturbative uncertainties. This calculation is then compared with those obtained with commonly used event generators, and we observe that the description of the considered kinematic regime provided by these tools is in good agreement with state of the art calculations. Finally, we present accurate predictions for other production channels such as vector boson fusion, and associated production with a gauge boson, and with a $t\bar{t}$ pair. We find that, at large transverse momentum, the contribution of other production modes is substantial, and therefore must be included for a precise theory prediction of this observable.

• Multiscale pentagon integrals to all orders

  Dhimiter D. Canko, Costas G. Papadopoulos, Nikolaos Syrrakos

  SciPost Phys. Proc. 7, 030 (2022) · published 21 June 2022 | Toggle abstract · pdf

  We present analytical results for one-loop five-point master integrals with up to three off-shell legs. The method of canonical differential equations along with the Simplified Differential Equations approach is employed. All necessary boundary terms are given in closed form, resulting to solutions in terms of Goncharov Polylogarithms of arbitrary weight. Explicit results up to weight six will be presented.

• Thermoelectric coefficients and the figure of merit for large open quantum dots

  Robert S. Whitney, Keiji Saito

  SciPost Phys. 6, 012 (2019) · published 24 January 2019 | Toggle abstract · pdf

  We consider the thermoelectric response of chaotic or disordered quantum dots in the limit of phase-coherent transport, statistically described by random matrix theory. We calculate the full distribution of the thermoelectric coefficients (Seebeck $S$ and Peltier $\Pi$), and the thermoelectric figure of merit $ZT$, for large open dots at arbitrary temperature and external magnetic field, when the number of modes in the left and right leads ($N_{\rm L}$ and $N_{\rm R}$) are large. Our results show that the thermoelectric coefficients and $ZT$ are maximal when the temperature is half the Thouless energy, and the magnetic field is negligible. They remain small, even at their maximum, but they exhibit a type of universality at all temperatures, in which they do not depend on the asymmetry between the left and right leads $(N_{\rm L}-N_{\rm R})$, even though they depend on $(N_{\rm L}+N_{\rm R})$.

• Recent Highlights on Higgs Physics from the LHC

  Elisabeth Schopf

  SciPost Phys. Proc. 8, 001 (2022) · published 11 July 2022 | Toggle abstract · pdf

  Many of the Higgs boson production and decay channels, predicted by the StandardModel, have been observed since its 2012 discovery. Today, measurements of the Higgsboson’s properties in these channels deepen our understanding of the nature of thisfundamental particle by providing better information about its mass, production kine-matics, and CP structure. Increasing precision also enables targeting rare Higgs bosondecay modes and probing di-Higgs-boson production. In addition, searches for beyondStandard Model physics in the Higgs sector are performed. This article presents the lat-est Higgs boson measurement highlights from the ATLAS and CMS collaborations usingLHC proton-proton collision data at a centre of mass energy of 13 TeV.

• Quantum oscillations in an impurity-band Anderson insulator

  Nigel R. Cooper, Jack Kelsall

  SciPost Phys. 15, 118 (2023) · published 27 September 2023 | Toggle abstract · pdf

  We show that for a system of localized electrons in an impurity band, which form an Anderson insulating state at zero temperature, there can appear quantum oscillations of the magnetization, i.e. the Anderson insulator can exhibit the de Haas-van Alphen effect. This is possible when the electronic band from which the localized states are formed has an extremum that traces out a nonzero area in reciprocal space. Our work extends existing theories for clean band insulators of this form to the situation where they host an impurity band. We show that the energies of these impurity levels oscillate with magnetic field, and compute the conditions under which these oscillations can dominate the de Haas-van Alphen effect. We discuss our results in connection with experimental measurements of quantum oscillations in Kondo insulators, and propose other experimental systems where the impurity band contribution can be dominant.

• Suppression of scattering from slow to fast subsystems and application to resonantly Floquet-driven impurities in strongly interacting systems

  Friedrich Hübner

  SciPost Phys. 16, 005 (2024) · published 5 January 2024 | Toggle abstract · pdf

  We study solutions to the Lippmann-Schwinger equation in systems where a slow subsystem is coupled to a fast subsystem via an impurity. Such situations appear when a high-frequency Floquet-driven impurity is introduced into a low-energy system, but the driving frequency is at resonance with a high-energy band. In contrast to the case of resonant bulk driving, where the particles in the low-energy system are excited into the high-energy band, we surprisingly find that these excitations are suppressed for resonantly driven impurities. Still, the transmission through the impurity is strongly affected by the presence of the high-energy band in a universal way that does not depend on the details of the high-energy band. We apply our general result to two examples and show the suppression of excitations from the low-energy band into the high-energy band: a) bound pairs in a Fermi-Hubbard chain scattering at a driven impurity, which is at resonance with the Hubbard interaction and b) particles in a deep optical lattice described by the tight-binding approximation, which scatter at a driven impurity, whose driving frequency equals the band gap between the two lowest energy bands.

• Prospects of measurements on the anomalous magnetic and electric dipole moments of the $\tau$-neutrino in $pp$ collisions at the LHC

  Alejandro Gutiérrez-Rodríguez, Murat Köksal, Ahmet A. Billur, Maria de los Ángeles Hernández-Ruíz

  SciPost Phys. Proc. 1, 044 (2019) · published 22 February 2019 | Toggle abstract · pdf

  In this paper the production cross-section $pp\rightarrow (\gamma, Z) \to \nu_\tau \bar \nu_\tau \gamma+X$ in $pp$ collisions at $\sqrt{s}=13, 14, 33\hspace{0.8mm}TeV$ is presented. Furthermore, we estimate bounds at the $95\%$ C.L. on the dipole moments of the $\tau$-neutrino using integrated luminosity of ${\cal L}= 100, 500, 1000, 3000 \hspace{0.8mm}fb^{-1}$ collected with the ATLAS detector at the LHC and we consider systematic uncertainties of $\delta_{sys} = 0\%, \, 5\%, \,10\%$. We found that the current and future LHC bounds are weaker than other experiments reported in the literature. However, it is shown that the process under consideration is a good prospect for probing the dipole moments of the $\tau$-neutrino at the LHC.

• Exact effective action for the O(N) vector model in the large N limit

  Han Ma, Sung-Sik Lee

  SciPost Phys. 15, 111 (2023) · published 22 September 2023 | Toggle abstract · pdf

  We present the Wilsonian effective action as a solution of the exact RG equation for the critical $O(N)$ vector model in the large $N$ limit. Below four dimensions, the exact effective action can be expressed in a closed form as a transcendental function of two leading scaling operators with infinitely many derivatives. From the exact solution that describes the RG flow from a UV theory to the fixed point theory in the IR, we obtain the mapping between UV operators and IR scaling operators. It is shown that IR scaling operators are given by sums of infinitely many UV operators with infinitely many derivatives.

• Experimental status of LNU in B decays in LHCb

  Sean Benson on behalf of the LHCb collaboration

  SciPost Phys. Proc. 1, 011 (2019) · published 19 February 2019 | Toggle abstract · pdf

  In the Standard Model, the three charged leptons are identical copies of each other, apart from mass differences. Experimental tests of this feature in semileptonic decays of b-hadrons are highly sensitive to New Physics particles which preferentially couple to the 2nd and 3rd generations of leptons. A review of the latest lepton universality tests in semileptonic $b\to c$ transitions at LHCb is reported.

• Three-loop soft anomalous dimensions in QCD

  Nikolaos Kidonakis

  SciPost Phys. Proc. 7, 046 (2022) · published 22 June 2022 | Toggle abstract · pdf

  I present results for soft anomalous dimensions through three loops for many QCD processes. In particular, I give detailed expressions for soft anomalous dimensions in various processes with electroweak and Higgs bosons as well as single top quarks and top-antitop pairs.