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We analyze the thermal history of the 2HDM and determine the parameter regions featuring a first-order electroweak phase transition (FOEWPT) and also much less studied phenomena like high-temperature electroweak (EW) symmetry non-restoration and the possibility of vacuum trapping (i.e. the Universe remains trapped in an EW-symmetric vacuum throughout the cosmological evolution, despite at $T=0$ the EW breaking vacuum is deeper). We show that the presence of vacuum trapping impedes a first-order EW phase transition in 2HDM parameter-space regions previously considered suitable for the realization of electroweak baryogenesis. Focusing then on the regions that do feature such a first-order transition, we show that the 2HDM parameter space that would yield a stochastic gravitational wave signal potentially detectable by the future LISA observatory is very contrived, and will be well probed by direct searches of 2HDM Higgs bosons at the HL-LHC, and (possibly) also via measurements of the self-coupling of the Higgs boson at 125 GeV. This has an important impact on the interplay between LISA and the LHC regarding the exploration of first-order phase transition scenarios in the 2HDM: the absence of new physics indications at the HL-LHC would severely limit the prospects of a detection by LISA. Finally, we demonstrate that as a consequence of the predicted enhancement of the self-coupling of the Higgs boson at 125 GeV the ILC would be able to probe the majority of the 2HDM parameter space yielding a FOEWPT through measurements of the self-coupling, with a large improvement in precision with respect to the HL-LHC. Comment: 41 pages, 13 figures

Particle accelerators are an important tool to study the fundamental properties of elementary particles. Currently the highest energy accelerator is the LHC at CERN, in Geneva, Switzerland. Each of its four major detectors, such as the CMS detector, produces dozens of Petabytes of data per year to be analyzed by a large international collaboration. The processing is carried out on the Worldwide LHC Computing Grid, that spans over more than 170 compute centers around the world and is used by a number of particle physics experiments. Recently the LHC experiments were encouraged to make increasing use of HPC resources. While Grid resources are homogeneous with respect to the used Grid middleware, HPC installations can be very different in their setup. In order to integrate HPC resources into the highly automatized processing setups of the CMS experiment a number of challenges need to be addressed. For processing, access to primary data and metadata as well as access to the software is required. At Grid sites all this is achieved via a number of services that are provided by each center. However at HPC sites many of these capabilities cannot be easily provided and have to be enabled in the user space or enabled by other means. At HPC centers there are often restrictions regarding network access to remote services, which is again a severe limitation. The paper discusses a number of solutions and recent experiences by the CMS experiment to include HPC resources in processing campaigns. 20th International Workshop on Advanced Computing and Analysis Techniques in Physics Research, ACAT 2021, Daejeon, Korea, Republic of, 29 Nov 2021 - 3 Dec 2021; Journal of physics / Conference Series 2438(1), 012039 (2023). doi:10.1088/1742-6596/2438/1/012039 Published by IOP Publ., Bristol

Motivated by the stunning projections for future CMB surveys, we evaluate the amount of dark radiation produced in the early Universe by two-body decays or binary scatterings with thermal bath particles via a rigorous analysis in momentum space. We track the evolution of the dark radiation phase space distribution, and we use the asymptotic solution to evaluate the amount of additional relativistic energy density parameterized in terms of an effective number of additional neutrino species $\Delta N_{\rm eff}$. Our approach allows for studying light particles that never reach equilibrium across cosmic history, and to scrutinize the physics of the decoupling when they thermalize instead. We incorporate quantum statistical effects for all the particles involved in the production processes, and we account for the energy exchanged between the visible and invisible sectors. Non-instantaneous decoupling is responsible for spectral distortions in the final distributions, and we quantify how they translate into the corresponding value for $\Delta N_{\rm eff}$. Finally, we undertake a comprehensive comparison between our exact results and approximated methods commonly employed in the existing literature. Remarkably, we find that the difference can be larger than the experimental sensitivity of future observations, justifying the need for a rigorous analysis in momentum space. Comment: 46 pages, 14 figures

Bulk composites using powder blends of Mn and Bi with equal atomic ratios are consolidated and severely deformed by high-pressure torsion (HPT). Subsequent annealing treatments lead to the formation of the ferromagnetic and rare-earth free hard magnetic α-MnBi phase. The initial phase formation is studied by in-situ high-energy XRD annealing experiments showing a beneficial influence of HPT-deformation on the amount of α-MnBi. The nucleation sites are strongly increased, thus the volumetric α-MnBi phase content exceeds 50 vol%. A lower HPT-pressure of 2 GPa is found to be preferred over 5 GPa to obtain high α-MnBi contents. Annealing is done with or without applying an external magnetic field. Additionally, influences of the HPT-induced shear deformation are discussed and correlated with preferred diffusion path ways fostering the formation of anisotropic α-MnBi phase. Journal of magnetism and magnetic materials 584, 171082 (2023). doi:10.1016/j.jmmm.2023.171082 Published by North-Holland Publ. Co., Amsterdam

Speckle-based experiments, in particular X-ray Photon Correlation Spectroscopy (XPCS), are among the ones that benefit most from the development of next generation light sources. The key quantity that determines whether or not it will be possible to perform an XPCS experiment is the speckle contrast β, which measures the visibility of the speckle pattern. The speckle contrast is influenced by geometrical conditions and light-source properties [1], and recently it has been noticed that artifacts in photon-counting detectors strongly interfere with the determination of the real value of β when the number of detected photons per frame is extremely low [2]. Here we report how the threshold setting of a photon counting detector, an EIGER X 4M, affects the detected contrast even at non extreme illumination conditions (0.01-0.05 photons/pixel/second). We found that by increasing the threshold value, not only leads to the expected drop in detected intensity, but also to a significant increase in the value of β. Additionally we will present an in-operando situation in which the higher threshold helps critically to increase the signal-to-noise ratio of the measured scattering pattern resulting in a five-fold increment of the speckle contrast. Journal of physics / Conference Series 2380(1), 012125 (2022). doi:10.1088/1742-6596/2380/1/012125 Published by IOP Publ., Bristol

Short-wavelength synchrotron radiation excitation has been an indispensable tool in the studies of the properties of wide gap materials using time-resolved low-temperature luminescence spectroscopy. In recent years, several setups for such investigations have been launched at MAX IV Laboratory and Photon Science at DESY. Two permanently stationed time-resolved luminescence setups at FinEstBeAMS and P66 beamlines are in operation at MAX IV 1.5 GeV and Petra III storage rings, respectively. Mobile luminescence setups have been developed for studies at FemtoMAX and P23 beamlines. FinEstBeAMS, P66 and P23 provide time resolution from ∼160 to 100 ps. The FemtoMAX photon source based on an in-vacuum undulator getting an electron beam from the 3 GeV linear accelerator provides an exceptional time resolution of ∼30 ps, limited by time response of the photodetector. The performance of the setups, achieved milestones and research challenges are discussed for four new luminescence stations available for the research community with the main focus on time-resolved techniques. Journal of physics / Conference Series 2380(1), 012135 (2022). doi:10.1088/1742-6596/2380/1/012135 Published by IOP Publ., Bristol

Thermoelectric transparent ZnO:Sb thin films were deposited by magnetron sputtering, with Sb content varying between 2 and 14 at%. As evidenced by X-ray diffraction analysis, the films crystallize in the ZnO wurtzite structure for lower levels of Sb-doping, developing a degree of amorphization for higher levels of Sb-doping. Temperature-dependent (10–300 K) X-ray absorption spectroscopy studies of the produced thin films were performed at the Zn and Sb K-edges to shed light on the influence of Sb doping on the local atomic structure and disorder in the ZnO:Sb thin films. The analysis of the Zn K-edge EXAFS spectra by the reverse Monte Carlo method allowed to extract detailed and accurate structural information in terms of the radial and bond angle distribution functions. The obtained results suggest that the introduction of antimony to the ZnO matrix promotes static disorder, which leads to partial amorphization with very small crystallites (∼3 nm) for large (12–14 at%) Sb content. Rutherford backscattering spectrometry (RBS) experiments enabled the determination of the in-depth atomic composition profiles of the films. The film composition at the surfaces determined by X-ray photoelectron spectroscopy (XPS) matches that of the bulk determined by RBS, except for higher Sb-doping in ZnO films, where the concentration of oxygen determined by XPS is smaller near the surface, possibly due to the formation of oxygen vacancies that lead to an increase in electrical conductivity. Traces of Sb–Sb metal bonds were found by XPS for the sample with the highest level of Sb-doping. Time-of-flight secondary ion mass spectrometry obtained an Sb/Zn ratio that follows that of the film bulk determined by RBS, although Sb is not always homogeneous, with samples with smaller Sb content (2 and 4 at% of Sb) showing a larger Sb content closer to the film/substrate interface. From the optical transmittance and reflectance curves, it was determined that the films with the lower amount of Sb doping have larger optical band-gaps, in the range of 2.9–3.2 eV, while the partially amorphous films with higher Sb content have smaller band-gaps in the range of 1.6–2.1 eV. Albeit the short-range crystalline order (∼3 nm), the film with 12 at% of Sb has the highest absolute Seebeck coefficient (∼56 μV/K) and a corresponding thermoelectric power factor of ∼0.2 μW·K−2·m−1. --//-- This is an open access article Joana M. Ribeiro, Frederico J. Rodrigues, Filipe C. Correia, Inga Pudza, Alexei Kuzmin, Aleksandr Kalinko, Edmund Welter, Nuno P. Barradas, Eduardo Alves, Alec P. LaGrow, Oleksandr Bondarchuk, Alexander Welle, Ahmad Telfah, Carlos J. Tavares, "The influence of Sb doping on the local structure and disorder in thermoelectric ZnO:Sb thin films", Journal of Alloys and Compounds, Volume 939, 2023, 168751, ISSN 0925-8388, https://doi.org/10.1016/j.jallcom.2023.168751 published under the CC BY licence. The experiment at HASYLAB/DESY was performed within the project I-20200161 EC. The research leading to this result has been supported by the project CALIPSOplus under the Grant Agreement 730872 from the EU Framework Programme for Research and Innovation HORIZON 2020. Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01–2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. This work was carried out in part through the use of the INL Advanced Electron Microscopy, Imaging and Spectroscopy Facility. This work (proposal ID 2018–020-022469) was carried out with the support of the Karlsruhe Nano Micro Facility (KNMFi, www.knmf.kit.edu), a Helmholtz Research Infrastructure at Karlsruhe Institute of Technology (KIT, www.kit.edu). Joana Ribeiro is grateful to the Fundação para a Ciência e Tecnologia (FCT, Portugal) for the Ph.D grant SFRH/BD/147221/2019. Filipe Correia is grateful to the FCT, Portugal, for the Ph.D. grant SFRH/BD/111720/2015. The authors also acknowledge the funding from FCT/PIDDAC through the Strategic Funds project reference UIDB/04650/2020–2023. Project I-20200161 EC; CALIPSOplus under the Grant Agreement 730872 from the EU Horizon 2020; FCT/PIDDAC through the Strategic Funds project reference UIDB/04650/2020–2023; institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01–2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.