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Evidence for Higgs boson decay to a pair of muons is presented. This result combines searches in four exclusive categories targeting the production of the Higgs boson via gluon fusion, via vector boson fusion, in association with a vector boson, and in association with a top quark-antiquark pair. The analysis is performed using proton-proton collision data at s√ = 13 TeV, corresponding to an integrated luminosity of 137 fb−1, recorded by the CMS experiment at the CERN LHC. An excess of events over the back- ground expectation is observed in data with a significance of 3.0 standard deviations, where the expectation for the standard model (SM) Higgs boson with mass of 125.38 GeV is 2.5. The combination of this result with that from data recorded at s√ = 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.7 fb−1, respectively, increases both the expected and observed significances by 1%. The measured signal strength, relative to the SM prediction, is 1.19+0.40−0.39(stat)+0.15−0.14(syst). This result constitutes the first evidence for the decay of the Higgs boson to second generation fermions and is the most precise measurement of the Higgs boson coupling to muons reported to date. Individuals have received support from the Marie-Curie programme and the European Research Council and Horizon 2020 Grant, contract Nos. 675440, 752730, and 765710 (European Union); the Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia María de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias. CMS collaboration: et al. Peer reviewed

We study the type-I seesaw model with three right-handed neutrinos and Majorana masses below the pion mass. In this mass range, the model parameter space is not only strongly constrained by the requirement to explain the light neutrino masses, but also by experimental searches and cosmological considerations. In the existing literature, three disjoint regions of potentially viable parameter space have been identified. In one of them, all heavy neutrinos decay shortly before big bang nucleosynthesis. In the other two regions, one of the heavy neutrinos either decays between BBN and the CMB decoupling or is quasi-stable. We show that previously unaccounted constraints from photodisintegration of nuclei practically rule out all relevant decays that happen between BBN and the CMB decoupling. Quite remarkably, if all heavy neutrinos decay before BBN, the baryon asymmetry of the universe can be quite generically explained by low-scale leptogenesis, i.e. without further tuning in addition to what is needed to avoid experimental and cosmological constraints. This motivates searches for heavy neutrinos in pion decay experiments. Journal of high energy physics 01(1), 200 (2021). doi:10.1007/JHEP01(2021)200 Published by SISSA, [Trieste]

Metriplectic systems are state space formulations that have become well-known under the acronym GENERIC. In this work we present a GENERIC based state space formulation in an operator setting that encodes a weak-formulation of the field equations describing the dynamics of a homogeneous mixture of compressible heat-conducting Newtonian fluids consisting of reactive constituents. We discuss the mathematical model of the fluid mixture formulated in the framework of continuum thermodynamics. The fluid mixture is considered an open thermodynamic system that moves free of external body forces. As closure relations we use the linear constitutive equations of the phenomenological theory known as Thermodynamics of Irreversible Processes (TIP). The phenomenological coefficients of these linear constitutive equations satisfy the Onsager-Casimir reciprocal relations. We present the state space representation of the fluid mixture, formulated in the extended GENERIC framework for open systems, specified by a symmetric, mixture related dissipation bracket and a mixture related Poisson-bracket for which we prove the Jacobi-identity.

Kurz gefasst Durch die mit den Rentenreformen 2001ff. eingeleitete Absenkung des Rentenniveaus ist das Risiko gestiegen, trotz langjähriger Systemzugehörigkeit und Beitragszahlung keinen Rentenanspruch oberhalb des Grundsicherungsniveaus zu erreichen, und es wird weiter steigen. Für Personen mit Niedrigeinkommen oder Teilzeitarbeit ist es auch bei langjähriger Versicherung kaum möglich, einen armutsvermeidenden Rentenanspruch oberhalb der Grundsicherungsschwelle zu erzielen. Das untergräbt die Akzeptanz der GRV als wichtigstem deutschen Alterssicherungssystem. Die Einführung einer Grundrente für langjährig Versicherte der GRV wurde im Koalitionsvertrag der GroKo für die laufende Legislaturperiode vereinbart. Das Vorhaben jetzt auch umzusetzen, ist ein Beitrag zum Vertrauen in das politische Handeln. Vor dem Hintergrund der in 2020 im Zuge der Corona-Pandemie beschlossenen Konjunkturpakete und ihrer Finanzvolumina erscheint das veranschlagte Finanzvolumen für die Grundrente (1,3 Mrd. € in 2021, steigend auf 1,6 Mrd. € 2025) moderat. Im Einzelnen wirft der nun vorliegende Gesetzentwurf allerdings noch eine Reihe von Fragen und Problemen auf. Hierzu gehören – neben absehbaren administrativen Herausforderungen – Fragen nach der gerechten Ausgestaltung (Arbeitszeiterfassung), dem Verhältnis zu anderen Sozialleistungen (Grundsicherung) und möglichen Fehlanreizen (Verfestigung geschlechtsspezifischer Arbeitszeitarrangements in der Familie). In Abgrenzung zur mehrheitlich vertretenen Auffassung, es handle sich bei der geplanten Grundrente um eine gesamtgesellschaftliche Aufgabe, die ggf. aus Steuern zu finanzieren sei, wird im Folgenden argumentiert, dass es sich hier um eine Versicherung gegen das Risiko, trotz langjähriger Mitgliedschaft und Beitragszahlung keine armutsvermeidenden Alterssicherungsansprüche aufbauen zu können handelt und daher eine Finanzierung aus Versicherungsbeiträgen sachgerecht wäre.

The purpose of this study is to examine if and how the EU CBAM influences the climate policy debate in Ukraine, one of the countries that is expected to be most affected due to its large share of carbon- intensive exports to the EU. The study seeks to find out how the EU CBAM can be made more instrumental in promoting an increase in the country���s climate policy ambition. IASS Study, October 2021

A search for charged Higgs boson decaying to a charm and a bottom quark ( $ {\mathrm{H}}^{+}\to \mathrm{c}\overline{\mathrm{b}} $ ) is performed using 19.7 fb$^{−1}$ of pp collision data at $ \sqrt{s}=8 $ TeV. The production mechanism investigated in this search is $ \mathrm{t}\overline{\mathrm{t}} $ pair production in which one top quark decays to a charged Higgs boson and a bottom quark and the other decays to a charged lepton, a neutrino, and a bottom quark. Charged Higgs boson decays to $ \mathrm{c}\overline{\mathrm{b}} $ are searched for, resulting in a final state containing at least four jets, a charged lepton (muon or electron), and missing transverse momentum. A kinematic fit is performed to identify the pair of jets least likely to be the bottom quarks originating from direct top quark decays and the invariant mass of this pair is used as the final observable in the search. No evidence for the presence of a charged Higgs boson is observed and upper limits at 95% confidence level of 0.8–0.5% are set on the branching fraction ℬ(t → H$^{+}$b), assuming ℬ(H$^{+}$ → $ \mathrm{c}\overline{\mathrm{b}} $ ) = 1.0 and ℬ(t → H$^{+}$b) + ℬ(t → Wb) = 1.0, for the charged Higgs boson mass range 90–150 GeV. Journal of high energy physics 1811(11), 115 (2018). doi:10.1007/JHEP11(2018)115 Published by Springer Nature, Cham

In this paper we develop an economic growth model that includes anthropogenic climate change. We include a publicly funded research sector that creates new technologies and simultaneously expands the productivities of existing technologies. The environment is affected by R&D activities both negatively, through the increase of output from productivity growth, as well as positively as new technologies are less harmful for the environment. We find that there may exist two different steadystates of the economy, depending on the amount of research spending: one with less new technologies being developed and the other with more technologies. Thus, a lock-in effect may arise that, however, can be overcome by raising R&D spending sufficiently such that the steady-state becomes unique. We derive the combinations of fiscal policy instruments for which that can be achieved and we study the implications for the economy and for the environment. In particular, the double dividend hypothesis may hold only under some specific conditions.

An angular analysis of $B^0\to J/\psi K^+\pi^-$ decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3~${\rm fb}^{-1}$ collected with the LHCb detector. The $m(K^+\pi^-)$ spectrum is divided into fine bins. In each $m(K^+\pi^-)$ bin, the hypothesis that the three-dimensional angular distribution can be described by structures induced only by $K^\ast$ resonances is examined, making minimal assumptions about the $K^+\pi^-$ system. The data reject the $K^\ast$-only hypothesis with a large significance, implying the observation of exotic contributions in a model-independent fashion. Inspection of the $m(J/\psi\pi^-)$ versus $m(K^+\pi^-)$ plane suggests structures near $m(J/\psi\pi^-)=4200$~MeV and 4600~MeV. Comment: All figures and tables, along with any supplementary material and additional information, are available at http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2018-043.html

Measurements of the second Fourier harmonic coefficient (v2) of the azimuthal distributions of prompt and nonprompt D0 mesons produced in pp and pPb collisions are presented. Nonprompt D0 mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, v2 signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum (pT) range of 2–6 GeV. Compared at similar event multiplicities, the prompt D0 meson v2 values in pp and pPb collisions are similar in magnitude. The v2 values for open beauty hadrons are extracted for the first time via nonprompt D0 mesons in pPb collisions. For pT in the range of 2–5 GeV, the results suggest that v2 for nonprompt D0 mesons is smaller than that for prompt D0 mesons. These new measurements indicate a positive charm hadron v2 in pp collisions and suggest a mass dependence in v2 between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. Individuals have received support from the Marie-Curie program and the European Research Council and Horizon 2020 Grant, contract Nos. 675440, 752730, and 765710 (European Union); CERN; the Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia María de Maeztu, grant MDM-2015-0509 and the Programa Severo Ochoa del Principado de Asturias. CMS Collaboration: et al. Funded by SCOAP3. Peer reviewed

The Tangerine project aims to develop new state-of-the-art high-precision silicon detectors. Part of the project has the goal of developing a monolithic active pixel sensor using a novel 65 nm CMOS imaging process, with a small collection electrode. This is the first application of this process in particle physics, and it is of great interest as it allows for an increased logic density and reduced power consumption and material budget compared to other processes. The process is envisioned to be used in for example the next ALICE inner tracker upgrade, and in experiments at the electron-ion collider. The initial goal of the three-year Tangerine project is to develop and test a sensor in a 65 nm CMOS imaging process that can be used in test beam telescopes at DESY, providing excellent spatial resolution and high time resolution, and thus demonstrating the capabilities of the process. The project covers all aspects of sensor R&D, from electronics and sensor design using simulations, to prototype test chip characterisation in labs and at test beams. The sensor design simulations are performed by using a powerful combination of detailed electric field simulations using technology computer-aided design and high-statistics Monte Carlo simulations using the Allpix Squared framework. A first prototype test chip in the process has been designed and produced, and successfully operated and tested both in labs and at test beams. The 16th Vienna Conference on Instrumentation, VCI2022, Vienna, Austria, 21 Feb 2022 - 25 Feb 2022; Nuclear instruments & methods in physics research / A 1039, 167025 (2022). doi:10.1016/j.nima.2022.167025 Published by North-Holland Publ. Co., Amsterdam