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Numrering	Referens	Omslagsbild	Hitta
1.	Acciari, V.A., et al. (författare) Monitoring the magnetar SGR 1935+2154 with the MAGIC telescopes 2022 Ingår i: Proceedings of Science. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract The Galactic magnetar SGR 1935+2154 was associated with a bright, millisecond-timescale fast radio burst (FRB) which occured in April 2020, during a flaring episode. This was the first time an FRB was unequivocally associated with a Galactic source, and the first FRB for which the nature of the emitting source was identified. Moreover, it was the first FRB with a counterpart at another wavelength correlated in time, an atypical, hard X-ray burst, which provides clear evidence for accompanying non-thermal processes. The MAGIC Telescopes are Imaging Air Cherenkov Telescopes (IACTs) sensitive to very-high-energy (VHE, E>100 GeV) gamma rays. Located at the center of the camera lies the MAGIC Central pixel, a single fully-modified photosensor-toreadout chain to measure millisecond-duration optical signals, displaying a maximum sensitivity at a wavelength of 350 nm. This allows MAGIC to operate simultaneously both as a VHE gammaray and a fast optical telescope. The MAGIC telescopes have monitored SGR 1935+2154 in a multiwavelength campaign involving X-ray, radio and optical facilities. In this contribution, we will show the results on the search for the VHE counterpart of the first SGR-FRB source in this multiwavelength context, as well as the search for fast optical bursts with the MAGIC Central Pixel.
2.	Acharya, S., et al. (författare) Antihelium-3 fluxes near Earth using data-driven estimates for annihilation cross section 2022 Ingår i: 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract Antinuclei found in cosmic rays could provide a smoking gun signal for dark matter as this signal is virtually background free. The study of 3He cosmic rays requires the knowledge of their production, propagation in the galaxy and annihilation cross-section. While the former two have been already estimated with data-driven methods, there were no experimental data available for the 3He inelastic cross section. We measured for the first time the inelastic cross section of 3He using the ALICE detector itself as a target. To study the effect of 3He annihilation in the galaxy and estimate the transparency of the galaxy, the 3He source functions and annihilation cross sections were implemented in GALPROP. © Copyright owned by the author(s) under the terms of the Creative Commons.
3.	Acharya, S., et al. (författare) Extending the ALICE strong-interaction studies to nuclei: measurement of proton-deuteron correlations in pp collisions at √s = 13 TeV 2022 Ingår i: The European Physical Society Conference on High Energy Physics. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 398 Konferensbidrag (refereegranskat)abstract The large data sample of high-multiplicity pp collisions collected by ALICE allows for the precise measurement of the size of source producing primary hadrons, opening the doors to a study of the interaction of different hadron species using femtoscopy techniques. The momentum correlation between (anti)protons and (anti)deuterons measured in pp collisions at √s = 13 TeV with ALICE is studied here for the first time. The measured correlation function for ((equation presented))p-((equation presented))d pairs is compared with theoretical predictions obtained considering Coulomb and Coulomb plus strong interactions and employing the Lednický-Lyuboshitz model with scattering parameters extracted from traditional scattering experiments for the p-d system. The measured correlation function can not be reproduced by any of the obtained predictions. This deviation can to large extent be interpreted as a demonstration of the late formation time of (anti)deuterons in hadron-hadron collisions. This observation is key for the understanding of the production mechanism of light (anti)nuclei, which is an open issue in high-energy physics and has also important consequences for the study of antinuclei formation in the interstellar medium either from collisions triggered by high-energy cosmic rays or by dark matter decays. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0)
4.	Alef, Walter, et al. (författare) BRAND - The next generation receiver for VLBI 2018 Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 344 Konferensbidrag (refereegranskat)abstract The aim of the BRAND EVN project is to build a very wide receiver prototype for primary focus with a frequency range from 1.5 GHz to 15.5 GHz In addition we will investigate solutions for secondary focus telescopes. The project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 730562 [RadioNet]. We present the status of the project which was started on January 1st, 2017 and is progressing smoothly: Feed, LNA, filters, major digital components, and some of the firmware are available now. © Copyright owned by the author(s) under the terms of the Creative Commons.
5.	Alnefjord, Joakim, et al. (författare) A Brief Look at the Chirality-Flow Formalism for Standard Model Amplitudes 2021 Ingår i: The Ninth Annual Conference on Large Hadron Collider Physics : LHCP2021 - LHCP2021. - 1824-8039. ; 397 Konferensbidrag (refereegranskat)abstract Inspired by the flow description of su(N) colour calculations, we recently showed how to simplify the spinor-helicity formalism (at the algebra level two copies of complexified su(2)) by treating each Weyl spinor as part of a flow line with definite chirality and momentum. This formalism, dubbed the chirality-flow formalism, eliminates all non-trivial algebra from tree-level spinor-helicity calculations, thus allowing the shortest possible route from Feynman diagrams to complex numbers (spinor inner products). In this presentation, we briefly introduce the main features of this method and show some examples.
6.	Ardenne, A. Van (författare) SKADS: Scope and overview of activities and results 2009 Ingår i: Proceedings of Science. - 1824-8039. ; 132, s. 9-14 Konferensbidrag (refereegranskat)abstract An introductory overview of the SKA Design Studies is given. This includes a short history, SKADS objectives, its structure and organization, its impact and an account of the work performed of which this SKADS Conference book bears full witness.
7.	Armstrong, T.P., et al. (författare) Monte Carlo Simulations and Validation of NectarCAM, a Medium Sized Telescope Camera for CTA 2022 Ingår i: 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract The upcoming Cherenkov Telescope Array (CTA) ground-based gamma-ray observatory will open up our view of the very high energy Universe, offering an improvement in sensitivity of 5-10 times that of previous experiments. NectarCAM is one of the proposed cameras for the Medium-Sized Telescopes (MST) which have been designed to cover the core energy range of CTA, from 100 GeV to 10 TeV. The final camera will be capable of GHz sampling and provide a field of view of 8 degrees with its 265 modules of 7 photomultiplier each (for a total of 1855 pixels). In order to validate the performance of NectarCAM, a partially-equipped prototype has been constructed consisting of only the inner 61-modules. It has so far undergone testing at the integration test-bench facility in CEA Paris-Saclay (France) and on a prototype of the MST structure in Adlershof (Germany). To characterize the performance of the prototype, Monte Carlo simulations were conducted using a detailed model of the 61 module camera in the CORSIKA/sim_telarray framework. This contribution provides an overview of this work including the comparison of trigger and readout performance on test-bench data and trigger and image parameterization performance during on-sky measurements. © Copyright owned by the author(s) under the terms of the Creative Commons.
8.	Aschersleben, J., et al. (författare) Application of pattern spectra and convolutional neural networks to the analysis of simulated Cherenkov Telescope Array data 2022 Ingår i: 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract The Cherenkov Telescope Array (CTA) will be the next generation gamma-ray observatory and will be the major global instrument for very-high-energy astronomy over the next decade, offering 5 − 10 × better flux sensitivity than current generation gamma-ray telescopes. Each telescope will provide a snapshot of gamma-ray induced particle showers by capturing the induced Cherenkov emission at ground level. The simulation of such events provides images that can be used as training data for convolutional neural networks (CNNs) to determine the energy of the initial gamma rays. Compared to other state-of-the-art algorithms, analyses based on CNNs promise to further enhance the performance to be achieved by CTA. Pattern spectra are commonly used tools for image classification and provide the distributions of the shapes and sizes of various objects comprising an image. The use of relatively shallow CNNs on pattern spectra would automatically select relevant combinations of features within an image, taking advantage of the 2D nature of pattern spectra. In this work, we generate pattern spectra from simulated gamma-ray events instead of using the raw images themselves in order to train our CNN for energy reconstruction. This is different from other relevant learning and feature selection methods that have been tried in the past. Thereby, we aim to obtain a significantly faster and less computationally intensive algorithm, with minimal loss of performance. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0)
9.	Azulay, R., et al. (författare) Binary stars in moving groups 2014 Ingår i: Proceedings of Science. - 1824-8039. ; 2014 Konferensbidrag (refereegranskat)abstract Precise determination of dynamical masses of pre-main-sequence (PMS) stars is necessary to calibrate PMS stellar evolutionary models, whose predictions are in disagreement with measurements for masses below 1.2M⊙. Binary stars in young, nearby loose associations are particularly good candidates, since all members share a common age. We present phase-reference EVN observations of the binary system HD 160934 A/c, that belongs to the ABDoradus moving group, from which we have measured both the relative and absolute orbital motion. Accordingly, we obtained precise estimates of the mass of the components of this binary. Also we report on other PMS binary systems as EKDra and AB DorB. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.
10.	Babiarz, Izabela, et al. (författare) The γ∗γ∗ → ηc(1S,2S) transition form factors for two spacelike photons 2019 Ingår i: European Physical Society Conference on High Energy Physics (EPS-HEP2019). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 364 Konferensbidrag (refereegranskat)abstract We discuss γ∗γ∗ → ηc(1S), ηc(2S) transition form factors for both virtual photons. The general formula is given. We use different models for the cc¯ wave function obtained from the solution of the Schrödinger equation for different cc¯ potentials: harmonic oscillator, Cornell, logarithmic, power-law, Coulomb and Buchmüller-Tye. We showed some examples of wave functions in the Light Front representation as well as in the rest frame of cc¯ pair. We compare our results to the BaBar experimental data for ηc(1S), for one real and one virtual photon, and to the values collected by the Particle Data Group for F(0,0), decay width Γγγ and decay constant fηc. We also considered the non-relativistic limit for F(0,0) form factor with the wave function at the origin R(0).
11.	Backes, M., et al. (författare) The Africa Millimetre Telescope 2016 Ingår i: Proceedings of Science. - 1824-8039. ; 2016-January Konferensbidrag (refereegranskat)abstract It is believed that supermassive black holes are found in the centres of galaxies, including the Milky Way. Still, only indirect evidence has been gathered for the existence of these enigmatic objects that are predicted by the general theory of relativity. With the Event Horizon Telescope, a Very Long Baseline Interferometry network of millimetre-wave (radio) telescopes, it will be possible to directly image the 'shadow' of the event horizon of the black hole at the centre of the Milky Way, Sgr A∗. Although the Event Horizon Telescope utilises an extensive network of telescopes, there is a huge gap in the coverage of the u-v-plane for these observations across Africa. We discuss the benefits of adding the Africa Millimetre Telescope to the Event Horizon Telescope and present Mt. Gamsberg in Namibia as the best site for this new and first mm-wave telescope in Africa.
12.	Beceiro-Novo, S., et al. (författare) Coulomb dissociation of 27 P: A reaction of astrophysical interest 2010 Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 100 Konferensbidrag (refereegranskat)abstract The ground-state decay of 26Al(0+) (T 1/2=1.05× 106) has a shorter life-time than the Universe. The presence of this element in the Galaxy was measured via g-ray spectroscopy, showing that the nucleosynthesis of this element is an ongoing process in stars. The proton-capture reaction 26Si(p,γ) 27P competes with the production of 26Al(0+) by β-decay. Coulomb dissociation of 27P has been suggested as an indirect method to measure radiative-proton capture when the direct reaction is not feasible. Such an experiment was performed at GSI with a secondary 27P beam produced by fragmenting a 36Ar primary beam at 500 A MeV. Two main observables are preliminarily presented in this work: the reaction cross section and the relative-energy spectrum of the outgoing fragments © Copyright owned by the author(s).
13.	Beck, R., et al. (författare) Structure, dynamical impact and origin of magnetic fields in nearby galaxies in the SKA era 2015 Ingår i: Proceedings of Science. - 1824-8039. ; 9-13-June-2014 Konferensbidrag (refereegranskat)abstract Magnetic fields are an important ingredient of the interstellar medium (ISM). Besides their importancefor star formation, they govern the transport of cosmic rays, relevant to the launch andregulation of galactic outflows and winds, which in turn are pivotal in shaping the structure of halomagnetic fields. Mapping the small-scale structure of interstellar magnetic fields in many nearbygalaxies is crucial to understand the interaction between gas and magnetic fields, in particularhow gas flows are affected. Elucidation of the magnetic role in, e.g., triggering star formation,forming and stabilising spiral arms, driving outflows, gas heating by reconnection and magnetisingthe intergalactic medium has the potential to revolutionise our physical picture of the ISMand galaxy evolution in general. Radio polarisation observations in the very nearest galaxies athigh frequencies (3 GHz) and with high spatial resolution (500) hold the key here. The galaxysurvey with SKA1 that we propose will also be a major step to understand the galactic dynamo,which is important for models of galaxy evolution and for astrophysical magnetohydrodynamicsin general. Field amplification by turbulent gas motions, which is crucial for efficient dynamoaction, has been investigated so far only in simulations, while compelling evidence of turbulentfields from observations is still lacking.
14.	Bellm, J., et al. (författare) Parton color reconnection in Herwig 7 using a spacetime event topology 2021 Ingår i: Proceedings of Science : 40th International Conference on High Energy physics (ICHEP2020) - 40th International Conference on High Energy physics (ICHEP2020). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 390 Konferensbidrag (refereegranskat)abstract Herwig 7 is a general-purpose Monte Carlo generator of particle collisions comprising both hard perturbative as well as soft phenomenological physics. Herwig is therefore capable to describe the entire final state of hadronized particles in a collision event. A spacetime topology of a parton system entering hadronization is fully described and tested for the first time. A combination of information from particles momenta and spacetime positions is utilized to minimize a boost-invariant distance measure of the parton system. We present a reasonable agreement of the model with a selection of experimental data and conclude that spacetime event topology can be meaningfully used in the further development.
15.	Beswick, R. J., et al. (författare) SKA studies of nearby galaxies: Star-formation, accretion processes and molecular gas across all environments 2014 Ingår i: Proceedings of Science. - 1824-8039. ; 9-13-June-2014 Konferensbidrag (refereegranskat)abstract The SKA will be a transformational instrument in the study of our local Universe. In particular, by virtue of its high sensitivity (both to point sources and diffuse low surface brightness emission), angular resolution and the frequency ranges covered, the SKA will undertake a very wide range of astrophysical research in the field of nearby galaxies. By surveying vast numbers of nearby galaxies of all types with mJy sensitivity and sub-arcsecond angular resolutions at radio wavelengths, the SKA will provide the cornerstone of our understanding of star-formation and accretion activity in the local Universe. In this chapter we outline the key continuum and molecular line science areas where the SKA, both during phase-1 and when it becomes the full SKA, will have a significant scientific impact.
16.	Bierlich, Christian (författare) Multiparton interactions and underlying event : A PYTHIA perspective 2021 Ingår i: 0th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions, HardProbes 2020. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 387 Konferensbidrag (refereegranskat)abstract We review recent developments in PYTHIA8, focused on heavy ion collisions. The ANGANTYR framework for heavy ion collisions is presented, as well as recent developments of the string shoving model for flow. It is further shown how string shoving can affect jet fragmentation in pp collisions. The effect of adding hadronic rescattering is reviewed, with focus on the nuclear modification factor, and finally ongoing work towards extending the PYTHIA8 and ANGANTYR MPI models to eletron-ion collisions is presented.
17.	Bijnens, Johan, et al. (författare) Analytical results for hadronic contributions to the muon g−2 2019 Ingår i: European Physical Society Conference on High Energy Physics (EPS-HEP2019). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 364 Konferensbidrag (refereegranskat)abstract This talk discusses two analytical calculations relevant for the Standard Model calculation of the muon g−2. The first part is the recent derivation of the quark-loop as the first term in a well-defined operator-product expansion for the short-distance part of the hadronic light-by-light contribution, as well as the calculation of the next term. The second part is the calculation of finite volume effects relevant for lattice QCD calculations of the electromagnetic contribution to the lowest-order hadronic vacuum-polarization contribution and the proof they only start at 1/L3
18.	Bijnens, Johan (författare) Chiral perturbation theory and mesons 2012 Ingår i: Proceedings of Science. - 1824-8039. ; 2012-August Tidskriftsartikel (refereegranskat)abstract The talk contains a short introduction to mesonic Chiral Perturbation Theory (ChPT). In addition four disparate areas where some progress has been made in recent years are discussed. These are the last fit of the order p4 low-energy-constants Lri to data, hard pion ChPT, the recent twoloop work on EFT for QCD like theories and the high order leading logarithm calculations in the massive O(N) nonlinear sigma model.
19.	Bijnens, Johan, et al. (författare) Leading logarithms for mesons and nucleons 2015 Ingår i: Proceedings of Science. - 1824-8039. Tidskriftsartikel (refereegranskat)abstract This talk describes the work done in calculating leading logarithms in massive effective field theories. We discuss shortly leading logarithms in renormalizable theories and how they can be calculated using only one-loop calculations in effective field theories. The remainder of the talk discusses masses, decay constants, condensates and anomalous processes in mesonic effective field theories like Chiral Perturbation Theory and the expansion of the nucleon mass.
20.	Bijnens, Johan, et al. (författare) Radiative and semileptonic decays in Chiral Perturbation Theory 2007 Ingår i: [Host publication title missing]. - 1824-8039. ; KAON, s. 027-027 Konferensbidrag (refereegranskat)abstract give a short overview of what has been done in radiative and semileptonic Kaon decays in Chiral Perturbation Theory. This includes for semileptonic decays the work which has been done to order p6 including preliminary results of isospin breaking to that order in Kl3. For the radiative decays I mainly present some results from recent work concerning Kl3gamma.
21.	Bijnens, Johan (författare) Status of Strong ChPT 2009 Ingår i: Proceedings of Science. - 1824-8039. ; 2009 Tidskriftsartikel (refereegranskat)abstract The present status of Chiral Perturbation Theory (ChPT) in the strong mesonic sector is discussed. A very short introduction to ChPT is followed by an overview of existing two-loop calculations and the determination of the Low-Energy-Constants (LECs). I discuss the case of $\eta\to\pi\pi\pi$ decays in somewhat more detail and finish by mentioning some recent work on partially quenched ChPT and on the renormalization group in ChPT.
22.	Bijnens, Johan (författare) Sunset integrals at finite volume 2013 Ingår i: Proceedings of Science. - 1824-8039. ; 29 Tidskriftsartikel (refereegranskat)abstract Chiral Perturbation Theory is a useful tool to aid in performing the various extrapolations needed in lattice QCD calculations of physical quantities. These include extrapolations in quark mass, finite lattice spacing and finite size of the lattice. Especially the latter will becomemore important when the quark masses on the lattice become smaller. Here we develop the needed two-loop integrals at finite volume to do the calculations for masses and decay constants for all general mass cases. I will present results based on an expansion in Bessel functions as well as on a version using theta functions and compare their efficiency. Work is in progress to combine these results with two-loop ChPT calculations.
23.	Bijnens, Johan, et al. (författare) The anomalous Lagrangian in ChPT at NNLO 2024 Ingår i: Proceedings of Science. - 1824-8039. ; 449 Konferensbidrag (refereegranskat)abstract The anomalous Lagrangian in mesonic Chiral Perturbation Theory, of odd intrinsic parity, is determined to next-to-next-to-leading order thereby completing the order p8 Lagrangian. A schematic view of its construction with the MINIBAR package for Mathematica is presented and the final operator count is discussed for a general number of light quark flavours as well as for the physical cases N f = 2, 3. The number of operators in our explicit construction of the Lagrangian basis is consistent with the number derived using the Hilbert series in the literature.
24.	Blennow, Mattias, 1980- (författare) Non-standard interactions using the OPERA experiment 2008 Ingår i: Proceedings of Science. - 1824-8039. ; NUFACT08 Tidskriftsartikel (refereegranskat)abstract We discuss the interplay of non-standard interactions between neutrinos and charged fermions and their impact on the currently running OPERA experiment. We show that, due to the relatively short distance between CERN and the Gran Sasso laboratory, the neutrino oscillation probabilities can be expanded in the baseline length. This results in a rather simple understanding of numeric simulations, which we perform using the GLoBES software. © owned by the author.
25.	Boguslavski, K., et al. (författare) Heavy quark diffusion coefficient during hydrodynamization - non-equilibrium vs. equilibrium 2024 Ingår i: Proceedings of Science. - 1824-8039. ; 438 Konferensbidrag (refereegranskat)abstract We compute the heavy quark momentum diffusion coefficient using effective kinetic theory for a system going through bottom-up isotropization until approximate hydrodynamization. We find that when comparing the nonthermal diffusion coefficient to the thermal one for the same energy density, the observed deviations throughout the whole evolution are within 30% from the thermal value. For thermal systems matched to other quantities we observe considerably larger deviations. We also observe that the diffusion coefficient in the transverse direction dominates at large occupation number, whereas for an underoccupied system the longitudinal diffusion coefficient dominates. Similarly, we study the jet quenching parameter, where we obtain a smooth evolution connecting the large values of the glasma phase with the smaller values in the hydrodynamical regime.
26.	Boyle, Peter, et al. (författare) Isospin-breaking corrections to light leptonic decays in lattice QCD+QED at the physical point 2023 Ingår i: The 39th International Symposium on Lattice Field Theory (LATTICE2022). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 430 Konferensbidrag (refereegranskat)abstract We report on the physical-point RBC/UKQCD calculation of the leading isospin-breaking corrections to light-meson leptonic decays. This is highly relevant for future precision tests in the flavour physics sector, in particular the first-row unitarity of the Cabibbo-Kobayashi-Maskawa matrix containing the elements Vus and Vud. The simulations were performed using Domain-Wall fermions for 2 + 1 flavours, and with isospin-breaking effects included perturbatively in the path integral through order α and (mu - md)/ΛQCD. We use QEDL for the inclusion of electromagnetism, and discuss here the non-locality of this prescription which has significant impact on the infinite-volume extrapolation.
27.	Brink, Lars, 1943 (författare) Héctor Rubinstein from a swedish prospective 2010 Ingår i: Hector Rubinstein Memorial Symposium: Quarks, Strings and the Cosmos, HRMS 2010; Stockholm; Sweden; 9 August 2010 through 11 August 2010. - 1824-8039. Konferensbidrag (refereegranskat)
28.	Brink, Lars, 1943 (författare) The nobel prize in physics 2013 the BEH - Mechanism, interactions with short range forces and scalar particles 2014 Ingår i: Proceedings of Science. - 1824-8039. ; 2014-September Konferensbidrag (refereegranskat)abstract On July 4, 2012, CERN announced the long awaited discovery of a new fundamental particle with properties similar to those expected for the missing link of the Standard Model (SM) of particle physics, the Higgs boson. The discovery was made independently by two experimental collaborations ATLAS and CMS at the Large Hadron Collider both working with huge all- purpose multichannel detectors. With significance at the level of five standard deviations, the new particle was mainly observed decaying into two channels: two photons and four leptons. This high significance implies that the probability of background fluctuations conspiring to produce the observed signal is less than 3×10 -7 . It took another nine months, however, and dedicated efforts from hundreds of scientists working hard to study additional decay channels and extract pertinent characteristics, before CERN boldly announced that the new particle was indeed the long-sought Higgs particle. Today we believe that "Beyond any reasonable doubt, it is a Higgs boson." [1]. An extensive review of Higgs searches prior to the July 2012 discovery may be found in [2] .
29.	Broggio, Alessandro, et al. (författare) tt̄X Calculations and Modeling 2021 Ingår i: The Ninth Annual Conference on Large Hadron Collider Physics : LHCP2021 - LHCP2021. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 397 Konferensbidrag (refereegranskat)abstract In this talk, we review the status of calculations for the associated production of a top pair and a Higgs, W or Z boson at the Large Hadron Collider. In particular, we focus on the resummation of soft gluon emission effects and on their combination with the complete set of next-to-leading-order corrections of both QCD and electroweak origin, in calculations in which the final state top pair and massive boson are kept on shell. The impact of these corrections on the total cross section and several differential distributions is studied.
30.	Brown, Anthony M., et al. (författare) Active Galactic Nuclei population studies with the Cherenkov Telescope Array 2022 Ingår i: 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract The Cherenkov Telescope Array (CTA) observatory is the next generation of ground-based imaging atmospheric Cherenkov telescopes (IACTs). Building on the strengths of current IACTs, CTA is designed to achieve an order of magnitude improvement in sensitivity, with unprecedented angular and energy resolution. CTA will also increase the energy reach of IACTs, observing photons in the energy range from 20 GeV to beyond 100 TeV. These advances in performance will see CTA heralding in a new era for high-energy astrophysics, with the emphasis shifting from source discovery, to population studies and precision measurements. In this talk we discuss CTA’s ability to conduct source population studies of γ-ray bright active galactic nuclei and how this ability will enhance our understanding on the redshift evolution of this dominant γ-ray source class. © Copyright owned by the author(s) under the terms of the Creative Commons.
31.	Burgman, Alexander, et al. (författare) The ESS neutrino super-beam near detector 2021 Ingår i: Proceedings of Science - SISSA. - 1824-8039. ; 398 Konferensbidrag (refereegranskat)abstract The ESS Neutrino Super-Beam (ESSnuSB) is a proposed long-baseline neutrino oscillation experiment, performed with a high-intensity neutrino beam, to be developed as an extension to the European Spallation Source proton linac currently under construction in Lund, Sweden. The neutrinos would be detected with the near and far detectors of the experiment, the former within several hundred meters of the neutrino production point and the latter within several hundred kilometers. The far detector will consist of a megaton-scale water-Cherenkov detector, and the near detector will consist of a kiloton-scale water-Cherenkov detector in combination with a fine-grained tracking detector and an emulsion detector. The purpose of the near detector is to constrain the flux of the neutrino beam as well as to extract the electron-neutrino interaction cross-section in water, which requires high-performance energy reconstruction and particle flavor identification techniques. These measurements are crucial for the neutrino oscillation measurements that will be conducted using the far detector. Year 2021 sees the finalization of the conceptual design of the near detector after a thorough evaluation of the performance of a number of different design options, and a characterization of the neutrino reconstruction and flavor identification performances. In this talk we report on these studies.
32.	Calibbi, Lorenzo, et al. (författare) Constraints on baryon number violation in supersymmetry from searches for neutron-antineutron oscillations and other observables 2016 Ingår i: Proceedings of Science. - 1824-8039. ; Part F128560 Konferensbidrag (refereegranskat)abstract Baryon number violation (BNV) in R-parity violating (RPV) supersymmetry is studied with a focus on ΔB = 2 processes which allow neutron-anti-neutron (n-n) oscillations. Simplified RPV-SUSY models, including only the relevant superpartners and couplings, are considered. Constraints from flavour physics, searches at the Large Hadron Collider and searches at dedicated BNV experiments are quantified for the various scenarios at the TeV scale. It is also shown that a proposed n-n experiment at the European Spallation Source has a sensitivity to a mass scale for new physics that goes beyond all other experiments and up to the PeV scale for certain regions of parameter space.
33.	Camargo-Molina, José Eliel, et al. (författare) Charged scalars from SU(3)3 theories 2016 Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 286 Konferensbidrag (refereegranskat)abstract Inspired by a recently proposed GUT model based on the trinification (SU(3)3) gauge group with a global family (SU(3)F) symmetry, we consider an effective low-energy three Higgs doublet model that may shed light on what underlies the observed fermion mass hierarchies and CKM mixing. We discuss possibilities for charged scalars coming from this model to show in collider experiments and show some interesting benchmark points.
34.	Camargo-Molina, José Eliel, et al. (författare) On a radiative origin of the standard model in non-supersymmetric trinification with global SU(3)F 2016 Ingår i: Proceedings of Science. - 1824-8039. ; Part F128560 Tidskriftsartikel (refereegranskat)abstract We present a trinification-based grand unified theory incorporating a global SU(3)F family symmetry, that after spontaneous symmetry breaking leads to a left-right symmetric model. In addition to unification of gauge couplings, the model unifies Yukawa interactions and contains equivalent representations in the scalar and fermion sectors at high energy scales. Considering the minimal low-energy scenario with the least amount of light states, we show that the resulting effective theory enables dynamical breaking of its gauge group to that of the Standard Model by means of radiative corrections accounted for by the renormalisation group evolution at leading order. This result paves the way for a possible explanation of the SM breaking scale and fermion mass hierarchies.
35.	Carney, Rebecca, 1990-, et al. (författare) Results of FE65-P2 Pixel Readout Test Chip for High Luminosity LHC Upgrades 2017 Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 282 Tidskriftsartikel (refereegranskat)abstract A pixel readout test chip called FE65-P2 has been fabricated on 65 nm CMOS technology. FE65-P2 contains a matrix of 64 x 64 pixels on 50 micron by 50 micron pitch, designed to read out a bump bonded sensor. The goals of FE65-P2 are to demonstrate excellent analog performance isolated from digital activity well enough to achieve 500 electron stable threshold, be radiation hard to at least 500 Mrad, and prove the novel concept of isolated analog front ends embedded in a flat digital design, dubbed “analog islands in a digital sea”. Experience from FE65-P2 and hybrid assemblies will be applied to the design for a large format readout chip, called RD53A, to be produced in a wafer run in early 2017 by the RD53 collaboration. We review the case for 65 nm technology and report on threshold stability test results for the FE65-P2.
36.	Carosi, Alessandro, et al. (författare) The Cherenkov Telescope Array transient and multi-messenger program 2022 Ingår i: 37th International Cosmic Ray Conference (ICRC2021) - GAI - Gamma Ray Indirect. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 395 Konferensbidrag (refereegranskat)abstract The Cherenkov Telescope Array (CTA) is a next generation ground-based very-high-energy gamma-ray observatory that will allow for observations in the >10 GeV range with unprecedented photon statistics and sensitivity. This will enable the investigation of the yet-marginally explored physics of short-time-scale transient events. CTA will thus become an invaluable instrument for the study of the physics of the most extreme and violent objects and their interactions with the surrounding environment. The CTA Transient program includes follow-up observations of a wide range of multi-wavelength and multi-messenger alerts, ranging from compact galactic binary systems to extragalactic events such as gamma-ray bursts (GRBs), core-collapse supernovae and bright AGN flares. In recent years, the first firm detection of GRBs by current Cherenkov telescope collaborations, the proven connection between gravitational waves and short GRBs, as well as the possible neutrino-blazar association with TXS 0506+056 have shown the importance of coordinated follow-up observations triggered by these different cosmic signals in the framework of the birth of multi-messenger astrophysics. In the next years, CTA will play a major role in these types of observations by taking advantage of its fast slewing (especially for the CTA Large Size Telescopes), large effective area and good sensitivity, opening new opportunities for time-domain astrophysics in an energy range not affected by selective absorption processes typical of other wavelengths. In this contribution we highlight the common approach adopted by the CTA Transients physics working group to perform the study of transient sources in the very-high-energy regime. © Copyright owned by the author(s) under the terms of the Creative Commons.
37.	Cederkall, Joakim, et al. (författare) The ESSνSB project 2020 Ingår i: European Physical Society Conference on High Energy Physics, EPS-HEP2019. - Trieste, Italy : Sissa Medialab srl. ; EPS-HEP2019 Konferensbidrag (refereegranskat)abstract The ESS nu SB project aims to produce a neutrino beam of unique intensity for a long-baseline oscillation measurement of CP-violation in the leptonic sector. The project, supported within the H2020 framework programme of the European Union, is currently in a conceptual design study phase, and work is ongoing within the project to develop viable solutions for the upgrade of the linear accelerator of the European Spallation Source (ESS), for the associated ring accumulator and the high-power target stations, as well as to establish solutions for the near and far detectors. The unique strength of the project lies in the capability to produce a neutrino beam that is intense enough to place the far detector at the second oscillation maximum. Such a placement will reduce the sensitivity of the experiment to systematic errors, which, due to the recently established value of the neutrino mixing angle theta(13), is now known to limit the measurement precision at the first oscillation maximum. In this paper we outline the basic components of the project and discuss the status of the ongoing conceptual design study.
38.	Chakraborty, Smita (författare) String shoving effects on jets in p-p collisions 2021 Ingår i: 10th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions, HardProbes 2020. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 387 Konferensbidrag (refereegranskat)abstract Di-jet observables are excellent probes to study the effect of jets in dense systems. Interacting Lund strings will affect jet observables and suggests a new common mechanism responsible for jet modification in p-A and A-A. In this proceeding, we present our new implementation of the string shoving mechanism in PYTHIA8 which lets us study the effects on jet observables in p-p and nuclear collisions. We also present preliminary results showing the effects in hadron-jet correlation studies.
39.	Christiansen, Jesper Roy (författare) Colour reconnection - Models and tests 2015 Ingår i: Proceedings of Science. - 1824-8039. ; 22-29-July-2015 Tidskriftsartikel (refereegranskat)abstract Recent progress on colour reconnection within the Pythia framework is presented. A new model is introduced, based on the SU(3) structure of QCD and a minimization of the potential string energy. The inclusion of the epsilon structure of SU(3) gives a new baryon production mechanism and makes it possible simultaneously to describe hyperon production at both e+e- and pp colliders. Finally, predictions for e+e-colliders, both past and potential future ones, are presented.
40.	Cimerman, Jakub, et al. (författare) The shape of the correlation function 2021 Ingår i: Proceedings of Science : 40th International Conference on High Energy physics (ICHEP2020) - 40th International Conference on High Energy physics (ICHEP2020). - 1824-8039. ; 390 Konferensbidrag (refereegranskat)abstract The correlation function measured in ultrarelativistic nuclear collisions is strongly non-Gaussian. Using two different models we study which effects can influence its shape and how much. In particular, we focus on the parametrizations expressed with the help of Lévy-stable distributions. We show that the Lévy index may deviate substantially from 2 due to non-critical effects such as resonance decays, event-by-event fluctuations and functional dependence on QLI or similar. We also study the corrections including the first-order Lévy expansion.
41.	Cirigliano, V., et al. (författare) A complete update of ε0/ε in the standard model 2019 Ingår i: European Physical Society Conference on High Energy Physics (EPS-HEP2019). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 364 Konferensbidrag (refereegranskat)abstract The recent release of improved lattice data has revived again the interest on precise theoretical calculations of the direct CP-violation ratio ε0/ε. We present a complete update of the Standard Model prediction [1,2], including a new re-analysis of isospin-breaking corrections which are of vital importance in the theoretical determination of this observable. The Standard Model prediction, Re(ε0/ε) = (14±5)·10−4, turns out to be in good agreement with the experimental measurement.
42.	Conway, John, 1963, et al. (författare) Radio properties of young SNe/SNRs in Arp220 2007 Ingår i: Proceedings of Science. - 1824-8039. ; 52 Konferensbidrag (refereegranskat)abstract Radio observations of young radio supernovae (SNe) and supernova remnants (SNRs) can provide a unique window on the stellar/ISM properties of starburst galaxies. Such observations can potentially constrain issues of cosmological importance such as whether stellar IMFs are radically different in extreme star-forming environments. Recently published observations of the nearest ultra-luminous infra-red galaxy Arp 220 have revealed the radio spectra of a group of SNe/SNR. About half of the sources detected at high frequency have spectral and variability properties consistent with young Type IIn supernovae interacting with their pre-explosion stellar winds. However the high rate of appearance of these sources implies that an unusually large fraction of core-collapse supernovae are highly luminous, which might be at least partly explained by a top heavy IMF. The other half of the compact sources found in Arp 220 were interpreted as SNRs interacting with a dense (104 to 105 cm−3) ISM. In this paper we report on new more sensitive VLBI observations at wavelengths of 2 cm and 3.6 cm. We find that the spectral evolution of most of the suspected SNe sources is consistent with them being of Type IIn. However two rapidly dimming objects may instead be of Type Ib/c or IIb. Most of the long-lived candidate SNR sources show small or undetectable flux density variations, however one almost doubled its 3.6 cm intensity in 11 months. Another source also shows some variability and a complex spectrum. These two objects plus another with a flat spectrum up to 2 cm are the best candidates for an AGN core, though the data does not yet require this interpretation. At least three sources show signs of resolution with diameters in the range 0.1 to 0.2 pc. These sizes put them sightly above, but still consistent with, the size-luminosity correlation for SNRs. The SKA will have sufficient sensitivity to detect the emission from Arp220-like compact sources out to cosmological distances (i.e. up to z≈ 0.5). However the SKA needs global baselines both to separate out the discrete sources from more extended radio emission and to resolve them apart.
43.	Conway, John, 1963 (författare) Scientific applications of e-VLBI 2009 Ingår i: Proceedings of Science. - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 82 Konferensbidrag (refereegranskat)abstract The advantages of e-VLBI over traditional media-recorded VLBI are briefly discussed. These advantages lie in two broad areas, those which reduce the operational burden of VLBI and those which enable wholly new kinds of observations to be made. In the first category, e-VLBI contributes to increases in reliability, to a more convenient way to use the instrument, reduced manpower effort and an easing of scheduling constraints. It also allows us to more easily expand bandwidth without building new recording equipment. In the second area the obvious advantage is in the increased speed of results from e-VLBI, which allows rapidly evolving sources to be observed and the next observations planned. A less appreciated, and yet to be fully realised e-VLBI advantage, especially when married to real time software correlation, is that of automation. Automated media-less operations will allow new types of long duration survey VLBI observations to be made lasting weeks to months. Potentially such a system could be used to create an always-on few telescope VLBI network which would follow up all suitable transient detections for accurate radio position and structure determination. An important and continuing benefit of the e-VLBI developments of recent years has been the closer integration and merging of connected element and long baseline interferometry via the e-MERLIN and e-LOFAR projects. The long term prospects for this synergy and the implications for long baseline centimetre wavelength interferometry in the era of the SKA are briefly mentioned.
44.	Corrigan, Eric Edward (författare) Analytical reinterpretation of ATLAS dark matter mediator searches with final-state jets 2019 Ingår i: Proceedings of Science. - 1824-8039. ; 367 Konferensbidrag (refereegranskat)abstract Understanding dark matter (DM) is one of the main challenges in modern high-energy physics and cosmology. Alongside direct and indirect detection experiments, one could also produce and discover DM in collider experiments, assuming there is some interaction between DM and Standard Model particles. One form this interaction could take is one mediated by a new vector or axial-vector boson. Furthermore, if DM can be resonantly produced by such a mechanism, the mediator itself could also be discovered by its decay back into quarks. One such search, using the LHC and the ATLAS detector, for jets with an associated photon in the final state, is described, together with an analytical method for the reinterpretation of non-discovery limits, for model parameters different from those used in simulation.
45.	Csörgo, T., et al. (författare) Lévy imaging of elastic scattering and proton hollowness at 13 TeV 2019 Ingår i: European Physical Society Conference on High Energy Physics (EPS-HEP2019). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 364 Konferensbidrag (refereegranskat)abstract The shape of elastic differential cross section within and beyond the diffractive cone at 13 TeV pp collision energy has been shown to be precisely described by the Lévy series expansion in whole available range of momentum transfers. This way, the crucial information about the real and imaginary parts of the elastic amplitude has been obtained resulting in precision reconstruction of the proton inelasticity profile. We have found that the profile function P(b) undergoes a qualitative change at √s ≈ 7 TeV collision energy. At small values of the impact parameter b a P(b) ≈ 1 plateaux develops, which becomes depressed at larger energies, such that a shallow minimum is formed near b = 0. We have evaluated the corresponding error bar and found such a hotly debated proton hollowness (or “black-ring”) effect with beyond 5σ significance.
46.	de Blok, W.J.G., et al. (författare) an overview of the MHONGOOSE survey: Observing nearby galaxies with MeerKAT 2016 Ingår i: Proceedings of Science. - 1824-8039. Konferensbidrag (refereegranskat)abstract MHONGOOSE is a deep survey of the neutral hydrogen distribution in a representative sample of 30 nearby disk and dwarf galaxies with H I masses from ∼ 106 to ∼ 1011 M, and luminosities from MR ∼ 12 to MR ∼ −22. The sample is selected to uniformly cover the available range in log(MHI). Our extremely deep observations, down to H I column density limits of well below 1018 cm−2 — or a few hundred times fainter than the typical H I disks in galaxies — will directly detect the effects of cold accretion from the intergalactic medium and the links with the cosmic web. These observations will be the first ever to probe the very low-column density neutral gas in galaxies at these high resolutions. Combination with data at other wavelengths, most of it already available, will enable accurate modeling of the properties and evolution of the mass components in these galaxies and link these with the effects of environment, dark matter distribution, and other fundamental properties such as halo mass and angular momentum. MHONGOOSE can already start addressing some of the SKA-1 science goals and will provide a comprehensive inventory of the processes driving the transformation and evolution of galaxies in the nearby universe at high resolution and over 5 orders of magnitude in column density. It will be a Nearby Galaxies Legacy Survey that will be unsurpassed until the advent of the SKA, and can serve as a highly visible, lasting statement of MeerKAT’s capabilities.
47.	Desmurs, J. F., et al. (författare) 28 SiO j=1-0, v=1, 2 & 3 maser emission from AGB stars 2012 Ingår i: Proceedings of Science. - 1824-8039. ; 2012-October Konferensbidrag (refereegranskat)abstract The v=1, 2 J=1–0 and v=1 J=2–1 are intense SiO masers, often mapped in AGB stars. Their distribution displays ring-like structures in the regions close to the star. The distribution of the v=1, 2 J=1–0 masers are similar, but the spots are rarely coincident. The v=1 J=2–1 maser ar-rises, however, from a well separated region. It has been argued that this difference can only be explained by models including overlap of two IR lines of SiO and H2O. The v=3 J=1–0 line is not expected to be affected by any line overlap, and its spot structure should be that predicted by the standard models. Our first results on the relative positions of the three lines are surprising but yet consistent with current models including line overlap.
48.	Desmurs, J. F., et al. (författare) First VLBA observations of 28SiO J=1-0, v=3 maser emission from AGB stars 2014 Ingår i: Proceedings of Science. - 1824-8039. ; 2014 Konferensbidrag (refereegranskat)abstract The v=1 & v=2 J=1-0 (43 GHz), and v=1 J=2-1 (86 GHz) SiO masers are intense in AGB stars. They have been mapped using VLBI displaying spots ring-like distributions. The rings of the v=1, v=2 J=1-0 masers are similar, but the spots are rarely coincident, while the v=1 J=2-1 maser arises from a well separated region farther out. The v=3 J=1-0 line is not directly affected by any line overlap and its spot structure and position, relative to the other lines, is a good test to the standard pumping models. We present simultaneous single dish and VLBI observations of the v=1, v=2, and v=3 J=1-0 maser transitions of 28SiO in several AGB stars and compare them to model predictions. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.
49.	Desmurs, J. F., et al. (författare) Resolving discrepancy in the pPN OH 231.8+4.2 2018 Ingår i: Proceedings of Science. - 1824-8039. ; 344 Konferensbidrag (refereegranskat)abstract OH 231.8+4.2 is an archetypal pre-planetary nebulae (pPN). It’s a binary system surrounded by bipolar nebula. Some years ago the authors extensively studied it and performed several VLBI observations from which they obtained mas-resolution maps of the SiO (7 mm) and H2O (1.3 cm) maser emissions (see [7]). H2O masers were found to be distributed in two areas along the symmetry axis of the nebulae oriented nearly north-south delineating a bipolar outflow and their astrometric positions were accurately measured. SiO masers, indicating the position of the Mira component of the binary system, form a structure perpendicular to the axis of the nebulae. The general picture of the source looked satisfactory, except for the relative position of the two masers. Surprisingly, SiO masers, were tentatively placed 250 mas away (370 AU) from the apparent center of the outflow. Using the ALMA we observed the SiO maser emission at 86 GHz and accurately derived the position of the Mira component. Combining our previous VLBA data and our new ALMA observations we are now able to give a more complete and detailed description of the inner part of this amazing pPN.
50.	Doglioni, Caterina (författare) Synergies between astroparticle, particle and nuclear physics 2019 Ingår i: European Physical Society Conference on High Energy Physics (EPS-HEP2019). - Trieste, Italy : Sissa Medialab. - 1824-8039. ; 364 Konferensbidrag (refereegranskat)abstract One overarching objective of science is to further our understanding of the universe, from its early stages to its current state and future evolution. This depends on gaining insight on the universe's most macroscopic components, for example galaxies and stars, as well as describing its smallest components, namely elementary particles and nuclei and their interactions. It is clear that this endeavour requires combined expertise from the fields of astroparticle physics, particle physics and nuclear physics. Pursuing common scientific drivers also require mastering challenges related to instrumentation (e.g. beams and detectors), data acquisition, selection and analysis, and making data and results available to the broader science communities. Joint work and recognition of these “foundational” topics will help all communities grow towards their individual and common scientific goals. The talk corresponding to this contribution has been presented during the special ECFA session of EPS-HEP 2019 focused on the update of the European Strategy of Particle Physics.

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