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Accidental SO(10) axion from gauged flavour
https://bib-pubdb1.desy.de/record/452306
An accidental U(1) Peccei-Quinn (PQ) symmetry automatically arises in a class of SO(10) unified theories upon gauging the SU(3)$_{f}$ flavour group. The PQ symmetry is protected by the ℤ$_{4}$ × ℤ$_{3}$ center of SO(10) × SU(3)$_{f}$ up to effective operators of canonical dimension six. However, high-scale contributions to the axion potential posing a PQ quality problem arise only at d = 9. In the pre-inflationary PQ breaking scenario the axion mass window is predicted to be m$_{a}$ ∈ [7 × 10$^{−8}$, 10$^{−3}$] eV, where the lower end is bounded by the seesaw scale and the upper end by iso-curvature fluctuations. A high-quality axion, that is immune to the PQ quality problem, is obtained for m$_{a}$ ≳ 2 0.02 eV. We finally offer a general perspective on the PQ quality problem in grand unified theories.Di Luzio, LucaWed, 25 Nov 2020 10:22:33 GMThttps://bib-pubdb1.desy.de/record/452306SISSA2020Axion quality from the (anti)symmetric of SU(N)
https://bib-pubdb1.desy.de/record/452305
We propose two models where a U(1) Peccei-Quinn global symmetry arises accidentally and is respected up to high-dimensional operators, so that the axion solution to the strong CP problem is successful even in the presence of Planck-suppressed operators. One model is SU($ \mathcal{N} $) gauge interactions with fermions in the fundamental and a scalar in the symmetric. The axion arises from spontaneous symmetry breaking to SO($ \mathcal{N} $), that confines at a lower energy scale. Axion quality in the model needs $ \mathcal{N} $ ≳ 10. SO bound states and possibly monopoles provide extra Dark Matter candidates beyond the axion. In the second model the scalar is in the anti-symmetric: SU($ \mathcal{N} $) broken to Sp($ \mathcal{N} $) needs even $ \mathcal{N} $ ≳ 20. The cosmological DM abundance, consisting of axions and/or super-heavy relics, can be reproduced if the PQ symmetry is broken before inflation (Boltzmann-suppressed production of super-heavy relics) or after (super-heavy relics in thermal equilibrium get partially diluted by dark glue-ball decays).Ardu, MarcoWed, 25 Nov 2020 10:19:41 GMThttps://bib-pubdb1.desy.de/record/452305SISSA2020High-frequency Graviton from Inflaton Oscillation
https://bib-pubdb1.desy.de/record/452304
We point out that there is a high-frequency tail of the stochastic inflationary gravitational wave background that scales as f−1/2 with frequency f. This contribution comes from the graviton vacuum fluctuation amplified by the inflaton coherent oscillation during the reheating stage when the inflaton is weakly coupled and the perturbative reheating picture is valid. Although the signal is typically very small, such a high-frequency tail contains information on inflaton properties such as the inflaton mass as well as the thermal history of the early Universe.Ema, YoheiWed, 25 Nov 2020 10:15:14 GMThttps://bib-pubdb1.desy.de/record/452304IOP2020Spontaneous Baryogenesis from Axions with Generic Couplings
https://bib-pubdb1.desy.de/record/452303
Axion-like particles can source the baryon asymmetry of our Universe through spontaneous baryogenesis. Here we clarify that this is a generic outcome for essentially any coupling of an axion-like particle to the Standard Model, requiring only a non-zero velocity of the classical axion field while baryon or lepton number violating interactions are present in thermal bath. In particular, coupling the axions only to gluons is sufficient to generate a baryon asymmetry in the presence of electroweak sphalerons or the Weinberg operator. Deriving the transport equation for an arbitrary set of couplings of the axion-like particle, we provide a general framework in which these results can be obtained immediately. If all the operators involved are efficient, it suffices to solve an algebraic equation to obtain the final asymmetries. Otherwise one needs to solve a simple set of differential equations. This formalism clarifies some theoretical subtleties such as redundancies in the axion coupling to the Standard Model particles associated with a field rotation. We demonstrate how our formalism automatically evades potential pitfalls in the calculation of the final baryon asymmetry.Domcke, Valerie FionaWed, 25 Nov 2020 10:11:50 GMThttps://bib-pubdb1.desy.de/record/452303SISSA2020RIP $H b \bar b$: How other Higgs production modes conspire to kill a rare signal at the LHC
https://bib-pubdb1.desy.de/record/452302
The hadroproduction of a Higgs boson in association with a bottom-quark pair ($H b \bar b$) is commonly considered as the key process for directly probing the Yukawa interaction between the Higgs boson and the bottom quark ($y_b$). However, in the Standard-Model (SM) this process is also known to suffer from very large irreducible backgrounds from other Higgs production channels, notably gluon-fusion ($gg$F). In this paper we calculate for the first time the so-called QCD and electroweak complete-NLO predictions for $H b \bar b$ production, using the four-flavour scheme. Our calculation shows that not only the $gg$F but also the $ZH$ and even the vector-boson-fusion channels are sizeable irreducible backgrounds. Moreover, we demonstrate that, at the LHC, the rate of these backgrounds is very large with respect to $H b \bar b$ production and in particular no suppression occurs at the differential level. Therefore, they survive typical analysis cuts. This fact further jeopardises the experimental measurement of SM $H b \bar b$ production at the LHC. Especially, unless the $y_b$ is significantly enlarged by new physics, even for beyond-the SM scenarios the direct determination of $y_b$ via this process seems to be hopeless at the LHC.Pagani, DavideWed, 25 Nov 2020 10:06:43 GMThttps://bib-pubdb1.desy.de/record/452302SISSA2020The light MSSM Higgs boson mass for large $\tan \beta $ and complex input parameters
https://bib-pubdb1.desy.de/record/452301
Bahl, HenningWed, 25 Nov 2020 10:03:34 GMThttps://bib-pubdb1.desy.de/record/452301Springer2020Complete leading-order standard model corrections to quantum leptogenesis
https://bib-pubdb1.desy.de/record/452300
Thermal leptogenesis, in the framework of the standard model with three additional heavy Majorana neutrinos, provides an attractive scenario to explain the observed baryon asymmetry in the universe. It is based on the out-of-equilibrium decay of Majorana neutrinos in a thermal bath of standard model particles, which in a fully quantum field theoretical formalism is obtained by solving Kadanoff-Baym equations. So far, the leading two-loop contributions from leptons and Higgs particles are included, but not yet gauge corrections. These enter at three-loop level but, in certain kinematical regimes, require a resummation to infinite loop order for a result to leading order in the gauge coupling. In this work, we apply such a resummation to the calculation of the lepton number density. The full result for the simplest “vanilla leptogenesis” scenario is by $ \mathcal{O} $(1) increased compared to that of quantum Boltzmann equations, and for the first time permits an estimate of all theoretical uncertainties. This step completes the quantum theory of leptogenesis and forms the basis for quantitative evaluations, as well as extensions to other scenarios.Depta, Paul FrederikWed, 25 Nov 2020 09:57:37 GMThttps://bib-pubdb1.desy.de/record/452300SISSA2020Zero-mode counting formula and zeros in orbifold compactifications
https://bib-pubdb1.desy.de/record/452299
We thoroughly analyze the number of independent zero modes and their zero points on the toroidal orbifold $T^2/\mathbb{Z}_N$ ($N = 2, 3, 4, 6$) with magnetic flux background, inspired by the Atiyah-Singer index theorem. We first show a complete list for the number $n_{\eta}$ of orbifold zero modes belonging to $\mathbb{Z}_{N}$ eigenvalue $\eta$. Since it turns out that $n_{\eta}$ quite complicatedly depends on the flux quanta $M$, the Scherk-Schwarz twist phase $(\alpha_1, \alpha_2)$, and the $\mathbb{Z}_{N}$ eigenvalue $\eta$, it seems hard that $n_{\eta}$ can be universally explained in a simple formula. We, however, succeed in finding a single zero-mode counting formula $n_{\eta} = (M-V_{\eta})/N + 1$, where $V_{\eta}$ denotes the sum of winding numbers at the fixed points on the orbifold $T^2/\mathbb{Z}_N$. The formula is shown to hold for any pattern.Sakamoto, MakotoWed, 25 Nov 2020 09:54:28 GMThttps://bib-pubdb1.desy.de/record/452299Inst.3023632020Weak gravity (and other conjectures) with broken supersymmetry19th Hellenic School and Workshops on Elementary Particle Physics and Gravity
https://bib-pubdb1.desy.de/record/452298
We study the weak gravity conjecture in non-supersymmetric string theory setups. Precisely, those are type I string theory with supersymmetry broken à la Scherk-Schwarz and open strings on D branes wrapped around magnetized tori in type II string theory. We compute long-range interactions between identical branes at one-loop and compare them to the weak gravity conjecture for higher-degree forms. In our examples, SUSY breaking generates interactions between branes, which are not anymore BPS, in such a way that the weak gravity conjecture is verified. In type I with the Scherk-Schwarz mechanism, the tension of the branes is reduced by one-loop quantum effects, so that there are long-range repulsive forces. The correlation of the non-vanishing brane potential with the presence of a running modulus and of possible D branes bound states nicely connects to other swampland conjectures. For magnetized branes in type II strings, we check that non-BPS branes experience a long-range repulsion whenever the open string spectrum is tachyon-free. Ultimately, the role of stringy objects in the discussion makes it compelling to further understand swampland conjectures in strings with broken SUSY, let alone their phenomenological relevance.Bonnefoy, Quentin Rene ChristianWed, 25 Nov 2020 09:48:35 GMThttps://bib-pubdb1.desy.de/record/452298Sissa Medialab Trieste, Italy2020Higgs inflation as nonlinear sigma model and scalaron as its $\sigma$-meson
https://bib-pubdb1.desy.de/record/452297
We point out that a model with scalar fields with a large nonminimal coupling to the Ricci scalar, such as Higgs inflation, can be regarded as a nonlinear sigma model (NLSM). With the inclusion of not only the scalar fields but also the conformal mode of the metric, our definition of the target space of the NLSM is invariant under the frame transformation. We show that the σ-meson that linearizes this NLSM to be a linear sigma model (LSM) corresponds to the scalaron, the degree of freedom associated to the R$^{2}$ term in the Jordan frame. We demonstrate that quantum corrections inevitably induce this σ-meson in the large-$N$ limit, thus providing a frame independent picture for the emergence of the scalaron. The resultant LSM only involves renormalizable interactions and hence its perturbative unitarity holds up to the Planck scale unless it hits a Landau pole, which is in agreement with the renormalizability of quadratic gravity.Ema, YoheiWed, 25 Nov 2020 09:43:16 GMThttps://bib-pubdb1.desy.de/record/452297SISSA2020No go for a flow
https://bib-pubdb1.desy.de/record/452296
We prove that a very large class of 15502 general Argyres-Douglas theories cannot admit a UV lagrangian which flows to them via the Maruyoshi-Song supersymmetry enhancement mechanism. We do so by developing a computer program which brute-force lists, for any given 4d $ \mathcal{N} $ = 2 superconformal theory $ \mathcal{T} _{IR}$, all possible UV candidate superconformal lagrangians $ \mathcal{T} _{UV}$ satisfying some necessary criteria for the supersymmetry enhancement to happen. We argue that this is enough evidence to conjecture that it is impossible, in general, to find new examples of Maruyoshi-Song lagrangians for generalized Argyres-Douglas theories. All lagrangians already known are, on the other hand, recovered and confirmed in our scan. Finally, we also develop another program to compute efficiently Coulomb branch spectrum, masses, couplings and central charges for (G, G′) Argyres-Douglas theories of arbitrarily high rank.Carta, FedericoWed, 25 Nov 2020 09:39:32 GMThttps://bib-pubdb1.desy.de/record/452296SISSA2020Resummed inclusive cross-section in ADD model at N$^{3}$LL
https://bib-pubdb1.desy.de/record/452295
We present three loop soft-plus-virtual (SV) corrections to the spin-2 production at the Large Hadron Collider (LHC). For this calculation, we make use of the recently computed quark and gluon three loop form factors for the spin-2 production, the universal soft-collinear coefficients as well as the mass factorization kernels. The SV coefficients are presented up to next-to-next-to-next-to leading order (N$^{3}$LO$_{sv}$). We also use these coefficients at three loops to compute the resummed prediction for inclusive cross-section to next-to-next-to-next-to leading logarithmic accuracy (N$^{3}$LL) matched to N$^{3}$LO$_{sv}$. We use the standard technique to derive the Mellin N-dependent coefficients and also the N-independent coefficients to achieve the resummation using the minimal prescription matching procedure. Considering the spin-2 propagator in the large extra dimensional (ADD) model, we also study the numerical impact of these three-loop SV corrections as well as the resummed predictions on the di-lepton invariant mass distribution at the 13 TeV LHC. We find that the conventional scale uncertainties in the N$^{3}$LO$_{sv}$ +N$^{3}$LL resummed results substantially get reduced to as low as 2% in the high invariant mass region. We also estimate the PDF uncertainties in our predictions that will be useful in the experimental searches for large extra dimensions.Das, GoutamWed, 25 Nov 2020 09:33:46 GMThttps://bib-pubdb1.desy.de/record/452295SISSA2020Dijet resonance search with weak supervision using $\sqrt{s}=13$ TeV $pp$ collisions in the ATLAS detector
https://bib-pubdb1.desy.de/record/452294
This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning is used to train classifiers directly on data to enhance potential signals. The targeted topology is dijet events and the features used for machine learning are the masses of the two jets. The resulting analysis is essentially a three-dimensional search A→BC, for $m_A∼O$(TeV), $m_B$, $m_C∼O$(100 GeV) and B, C are reconstructed as large-radius jets, without paying a penalty associated with a large trials factor in the scan of the masses of the two jets. The full run 2$\sqrt{s}$ =13 TeV $pp$ collision dataset of 139 fb$^{-1}$ recorded by the ATLAS detector at the Large Hadron Collider is used for the search. There is no significant evidence of a localized excess in the dijet invariant mass spectrum between 1.8 and 8.2 TeV. Cross-section limits for narrow-width A, B, and C particles vary with $m_A$, $m_B$, and $m_C$. For example, when $m_A$=3 TeV and $m_B$≳200 GeV, a production cross section between 1 and 5 fb is excluded at 95% confidence level, depending on $m_C$. For certain masses, these limits are up to 10 times more sensitive than those obtained by the inclusive dijet search. These results are complementary to the dedicated searches for the case that B and C are standard model bosons.Aad, GeorgesWed, 25 Nov 2020 09:33:24 GMThttps://bib-pubdb1.desy.de/record/452294APS2020Langenscheidt Fachwörterbuch Kompakt Bauwesen Englisch: Englisch-Deutsch/Deutsch-Englisch
https://bib-pubdb1.desy.de/record/452293
Wed, 25 Nov 2020 09:19:39 GMThttps://bib-pubdb1.desy.de/record/452293urn:ISBN:978-3-12-514089-9Langenscheidt bei PONS2011Search for new non-resonant phenomena in high-mass dilepton final states with the ATLAS detector
https://bib-pubdb1.desy.de/record/452292
A search for new physics with non-resonant signals in dielectron and dimuon final states in the mass range above 2 TeV is presented. This is the first search for non-resonant signals in dilepton final states at the LHC to use a background estimate from the data. The data, corresponding to an integrated luminosity of 139 fb$^{−1}$, were recorded by the ATLAS experiment in proton-proton collisions at a center-of-mass energy of $ \sqrt{s} $ = 13 TeV during Run 2 of the Large Hadron Collider. The benchmark signal signature is a two-quark and two-lepton contact interaction, which would enhance the dilepton event rate at the TeV mass scale. To model the contribution from background processes a functional form is fit to the dilepton invariant-mass spectra in data in a mass region below the region of interest. It is then extrapolated to a high-mass signal region to obtain the expected background there. No significant deviation from the expected background is observed in the data. Upper limits at 95% CL on the number of events and the visible cross-section times branching fraction for processes involving new physics are provided. Observed (expected) 95% CL lower limits on the contact interaction energy scale reach 35.8 (37.6) TeV.[graphic not available: see fulltext]Aad, GeorgesWed, 25 Nov 2020 08:45:07 GMThttps://bib-pubdb1.desy.de/record/452292SISSA2020Search for $ t\overline{t} $ resonances in fully hadronic final states in $pp$ collisions at $ \sqrt{s} $ = 13 TeV with the ATLAS detector
https://bib-pubdb1.desy.de/record/452291
This paper presents a search for new heavy particles decaying into a pair of top quarks using 139 fb$^{−1}$ of proton-proton collision data recorded at a centre-of-mass energy of $ \sqrt{s} $ = 13 TeV with the ATLAS detector at the Large Hadron Collider. The search is performed using events consistent with pair production of high-transverse-momentum top quarks and their subsequent decays into the fully hadronic final states. The analysis is optimized for resonances decaying into a $ t\overline{t} $ pair with mass above 1.4 TeV, exploiting a dedicated multivariate technique with jet substructure to identify hadronically decaying top quarks using large-radius jets and evaluating the background expectation from data. No significant deviation from the background prediction is observed. Limits are set on the production cross-section times branching fraction for the new Z′ boson in a topcolor-assisted-technicolor model. The Z′ boson masses below 3.9 and 4.7 TeV are excluded at 95% confidence level for the decay widths of 1% and 3%, respectively.Aad, GeorgesWed, 25 Nov 2020 08:37:16 GMThttps://bib-pubdb1.desy.de/record/452291SISSA2020Search for Magnetic Monopoles and Stable High-Electric-Charge Objects in 13 Tev Proton-Proton Collisions with the ATLAS Detector
https://bib-pubdb1.desy.de/record/452290
A search for magnetic monopoles and high-electric-charge objects is presented using 34.4 fb$^{-1}$ of 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015 and 2016. The considered signature is based upon high ionization in the transition radiation tracker of the inner detector associated with a pencil-shape energy deposit in the electromagnetic calorimeter. The data were collected by a dedicated trigger based on the tracker high-threshold hit capability. The results are interpreted in models of Drell-Yan pair production of stable particles with two spin hypotheses (0 and 1/2) and masses ranging from 200 to 4000 GeV. The search improves by approximately a factor of 5 the constraints on the direct production of magnetic monopoles carrying one or two Dirac magnetic charges and stable objects with electric charge in the range 20≤|z|≤60 and extends the charge range to 60<|z|≤100.Aad, GeorgesWed, 25 Nov 2020 08:14:21 GMThttps://bib-pubdb1.desy.de/record/452290APS2020Molecular to Macroscale Energy Absorption Mechanisms in Biological Body Armour Illuminated by Scanning X-ray Diffraction with In Situ Compression
https://bib-pubdb1.desy.de/record/452269
Determining multiscale, concurrent strain, and deformation mechanisms in hierarchical biological materials is a crucial engineering goal, to understand structural optimization strategies in Nature. However, experimentally characterizing complex strain and displacement fields within a 3D hierarchical composite, in a multiscale full-field manner, is challenging. Here, we determined the in situ strains at the macro-, meso-, and molecular-levels in stomatopod cuticle simultaneously, by exploiting the anisotropy of the 3D fiber diffraction coupled with sample rotation. The results demonstrate the method, using the mineralized 3D α-chitin fiber networks as strain sensors, can capture submicrometer deformation of a single lamella (mesoscale), can extract strain information on multiple constituents concurrently, and shows that α-chitin fiber networks deform elastically while the surrounding matrix deforms plastically before systematic failure under compression. Further, the results demonstrate a molecular-level prestrain gradient in chitin fibers, resulting from different mineralization degrees in the exo- and endo cuticle.Zhang, YiTue, 24 Nov 2020 18:51:18 GMThttps://bib-pubdb1.desy.de/record/452269Soc.2020Resummed Drell-Yan cross-section at N$^{3}$LL
https://bib-pubdb1.desy.de/record/452268
We present the resummed predictions for inclusive cross-section for Drell-Yan (DY) production as well as onshell Z, W$^{±}$ productions at next-to-next-to-next-to leading logarithmic (N$^{3}$LL) accuracy. Using the standard techniques, we derive the N-dependent coefficients in the Mellin-N space as well as the N-independent constants and match the resummed result through the minimal prescription procedure with the fixed order results. In addition to the standard ln N exponentiation, we study the numerical impacts of exponentiating N-independent part of the soft function and the complete $ {\overline{g}}_0 $ that appears in the resummed predictions in N space. All the analytical pieces needed in these different approaches are extracted from the soft-virtual part of the inclusive cross section known to next-to-next-to-next-to leading order (N$^{3}$LO). We perform a detailed analysis on the scale and parton distribution function (PDF) variations and present predictions for 13 TeV LHC for the neutral Drell-Yan process as well as onshell charged and neutral vector boson productions.Ajjath, A. H.Tue, 24 Nov 2020 12:48:32 GMThttps://bib-pubdb1.desy.de/record/452268SISSA2020Big science and research infrastructures in Europe
https://bib-pubdb1.desy.de/record/452266
Hallonsten, OlofTue, 24 Nov 2020 12:37:09 GMThttps://bib-pubdb1.desy.de/record/452266urn:ISBN:978183910000Edward Elgar Publishing2020Neutrino Detectors Under Water and Ice
https://bib-pubdb1.desy.de/record/452265
Underwater/ice neutrino telescopes are multi-purpose detectors covering astrophysical, particle physics and environmental aspects. Among them, the detection of the feeble fluxes of astrophysical neutrinos which should accompany the production of high energy cosmic rays is the clear primary goal. Since these neutrinos can escape much denser celestial bodies than light, they can trace processes hidden to traditional astronomy. Different to gamma rays, neutrinos provide incontrovertible evidence for hadronic acceleration. On the other hand, their extremely low interaction cross section makes their detection extraordinarily difficult.Spiering, ChristianTue, 24 Nov 2020 12:36:38 GMThttps://bib-pubdb1.desy.de/record/452265Springer International Publishing2020Combined search for neutrinos from dark matter self-annihilation in the Galactic Center with ANTARES and IceCube
https://bib-pubdb1.desy.de/record/452264
We present the results of the first combined dark matter search targeting the Galactic Center using the ANTARES and IceCube neutrino telescopes. For dark matter particles with masses from 50 to 1000 GeV, the sensitivities on the self-annihilation cross section set by ANTARES and IceCube are comparable, making this mass range particularly interesting for a joint analysis. Dark matter self-annihilation through the $τ^+τ^-$, $μ^+μ^-$, $bb^¯$, and $W^+W^-$ channels is considered for both the Navarro-Frenk-White and Burkert halo profiles. In the combination of 2101.6 days of ANTARES data and 1007 days of IceCube data, no excess over the expected background is observed. Limits on the thermally averaged dark matter annihilation cross section ⟨$σ_Aυ$⟩ are set. These limits present an improvement of up to a factor of 2 in the studied dark matter mass range with respect to the individual limits published by both collaborations. When considering dark matter particles with a mass of 200 GeV annihilating through the $τ^+τ^-$ channel, the value obtained for the limit is 7.44 × 10$^{-24}$ cm$^3$ s$^{-1}$ for the Navarro-Frenk-White halo profile. For the purpose of this joint analysis, the model parameters and the likelihood are unified, providing a benchmark for forthcoming dark matter searches performed by neutrino telescopes.Albert, A.Tue, 24 Nov 2020 12:16:29 GMThttps://bib-pubdb1.desy.de/record/452264Inst.3023632020Design and Performance of the first IceAct Demonstrator at the South Pole
https://bib-pubdb1.desy.de/record/452263
In this paper we describe the first results of a compact imaging air-Cherenkov telescope, IceAct, operating in coincidence with the IceCube Neutrino Observatory (IceCube) at the geographic South Pole. An array of IceAct telescopes (referred to as the IceAct project) is under consideration as part of the IceCube-Gen2 extension to IceCube. Surface detectors in general will be a powerful tool in IceCube-Gen2 for distinguishing astrophysical neutrinos from the dominant backgrounds of cosmic-ray induced atmospheric muons and neutrinos: the IceTop array is already in place as part of IceCube, but has a high energy threshold. Although the duty cycle will be lower for the IceAct telescopes than the present IceTop tanks, the IceAct telescopes may prove to be more effective at lowering the detection threshold for air showers. Additionally, small imaging air-Cherenkov telescopes in combination with IceTop, the deep IceCube detector or other future detector systems might improve measurements of the composition of the cosmic ray energy spectrum. In this paper we present measurements of a first 7-pixel imaging air Cherenkov telescope demonstrator, proving the capability of this technology to measure air showers at the South Pole in coincidence with IceTop and the deep IceCube detector.Aartsen, M. G.Tue, 24 Nov 2020 11:53:30 GMThttps://bib-pubdb1.desy.de/record/452263Inst. of Physics2019Operation of the ATLAS trigger system in Run 2
https://bib-pubdb1.desy.de/record/452261
The ATLAS experiment at the Large Hadron Collider employs a two-level trigger system to record data at an average rate of 1 kHz from physics collisions, starting from an initial bunch crossing rate of 40 MHz. During the LHC Run 2 (2015–2018), the ATLAS trigger system operated successfully with excellent performance and flexibility by adapting to the various run conditions encountered and has been vital for the ATLAS Run-2 physics programme. For proton-proton running, approximately 1500 individual event selections were included in a trigger menu which specified the physics signatures and selection algorithms used for the data-taking, and the allocated event rate and bandwidth. The trigger menu must reflect the physics goals for a given data collection period, taking into account the instantaneous luminosity of the LHC and limitations from the ATLAS detector readout, online processing farm, and offline storage. This document discusses the operation of the ATLAS trigger system during the nominal proton-proton data collection in Run 2 with examples of special data-taking runs. Aspects of software validation, evolution of the trigger selection algorithms during Run 2, monitoring of the trigger system and data quality as well as trigger configuration are presented.Aad, GeorgesTue, 24 Nov 2020 09:10:42 GMThttps://bib-pubdb1.desy.de/record/452261Inst. of Physics2020Open Science & DEALDirektoriumssitzung
https://bib-pubdb1.desy.de/record/452240
Köhler, MartinMon, 23 Nov 2020 21:09:48 GMThttps://bib-pubdb1.desy.de/record/4522402020