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Fourth post-Newtonian Hamiltonian dynamics of two-body systems from an effective field theory approach
No full textWe calculate the motion of binary mass systems in gravity up to the fourth post--Newtonian order. We use momentum expansions within an effective field theory approach based on Feynman amplitudes in harmonic coordinates by applying dimensional regularization. We construct the canonical transformations to ADM coordinates and to effective one body theory (EOB) to compare with other approaches. We show that intermediate poles in the dimensional regularization parameter vanish in the observables and the classical theory is not renormalized. The results are illustrated for a series of observables for which we agree with the literature
Search for charged Higgs bosons decaying into a top and a bottom quark in the all-jet final state of pp collisions at 13 TeV
No full textA search for charged Higgs bosons (H) decaying into a top and a bottom quark in the all-jet final states is presented. The analysis uses LHC proton-proton collision data recorded with the CMS detector in 2016 at 13 TeV, corresponding to an integrated luminosity of 35.9 fb. No significant excess is observed above the expected background. Model-independent upper limits at 95% confidence level are set on the product of the H production cross section and branching fraction in two scenarios. For production in association with a top quark, limits of 21.3 to 0.007 pb are obtained for H masses in the range of 0.2 to 3 TeV. Combining this with data from a search in leptonic final states results in improved limits of 9.25 to 0.005 pb. The complementary -channel production of an H is investigated in the mass range of 0.8 to 3 TeV and the corresponding upper limits are 4.5 to 0.023 pb. These results are interpreted using different minimal supersymmetric extensions of the standard model
Plasma Lenses: Possible alternative OMD at the ILC
No full textIn the baseline design of the International Linear Collider (ILC) an undulator-based source is foreseen for the positron source in order to match the physics requirements. The recently chosen first energy stage with sqrt(s)=250 GeV requires high luminosity and imposes an effort for all positron source designs at high-energy colliders. In this paper we perform a simulation study and adopt the new technology of plasma lenses to capture the positrons generated by the undulator photons and to create the required high luminosity positron beam
Atomic Scale Design of Spinel Nanocrystal Synthesis
No full textThe chemistry of ZnAlO nanocrystal nucleation and growth is examined by X-ray scattering methods, and the results challenge the conventional understanding of its preparation by hydrothermal methods. The common assumption that a specific metal to hydroxide ion (M/OH) ratio is necessary to achieve a phase-pure product is shown to be inadequate. Pair distribution function analysis is used to identify distinct precursor structures, providing an understanding of why particular impurity phases are observed under certain M/OH ratios as heating is applied. In situ X-ray diffraction studies then probe the ZnAlO growth in real time, from which optimal synthesis conditions and the influence of impurities is established. It is found that the heating rate plays a dominant role in impurity formation and dissolution. This observation is explored in three different hydrothermal synthesis methods (microwave, autoclave, and supercritical flow) having different intrinsic heating rates, and methodologies to prepare phase-pure ZnAlO were successfully developed in each case. Ultimately, the atomic scale X-ray scattering information provides concrete guidance to tune the crystallite size, band gap, morphology, and defects of ZnAlO nanocrystals in hydrothermal synthesis establishing a bottom up nonempirical approach to synthesis design
Higgs Boson studies at future particle colliders
No full textThis document aims to provide an assessment of the potential of future colliding beam facilities to perform Higgs boson studies. The analysis builds on the submissions made by the proponents of future colliders to the European Strategy Update process, and takes as its point of departure the results expected at the completion of the HL-LHC program. This report presents quantitative results on many aspects of Higgs physics for future collider projects of sufficient maturity using uniform methodologies
Impact of isolation and fiducial cuts on q and N-jettiness subtractions
No full textKinematic selection cuts and isolation requirements are a necessity in experimental measurements for identifying prompt leptons and photons that originate from the hard-interaction process of interest. We analyze how such cuts affect the application of the and -jettiness subtraction methods for fixed-order calculations. We consider both fixed-cone and smooth-cone isolation methods. We find that kinematic selection and isolation cuts both induce parametrically enhanced power corrections with considerably slower convergence compared to the standard power corrections that are already present in inclusive cross sections without additional cuts. Using analytic arguments at next-to-leading order we derive their general scaling behavior as a function of the subtraction cutoff. We also study their numerical impact for the case of gluon-fusion Higgs production in the decay mode and for direct diphoton production. We find that the relative enhancement of the additional cut-induced power corrections tends to be more severe for , where it can reach an order of magnitude or more, depending on the choice of parameters and subtraction cutoffs. We discuss how all such cuts can be incorporated without causing additional power corrections by implementing the subtractions differentially rather than through a global slicing method. We also highlight the close relation of this formulation of the subtractions to the projection-to-Born method
Weak gravity (and other conjectures) with broken supersymmetry
No full textWe study the weak gravity conjecture in non-supersymmetric string theory setups. Precisely, those are type I string theory with supersymmetry broken \`a 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
A Decade of Multiwavelength Observations of the TeV Blazar 1ES 1215+303: Extreme Shift of the Synchrotron Peak Frequency and Long-term Optical–Gamma-Ray Flux Increase
No full textBlazars are known for their variability on a wide range of timescales at all wavelengths. Most studies of TeV gamma-ray blazars focus on short timescales, especially during flares. With a decade of observations from the Fermi-LAT and VERITAS, we present an extensive study of the long-term multi-wavelength radio-to-gamma-ray flux-density variability, with the addition of a couple of short-time radio-structure and optical polarization observations of the blazar 1ES 1215+303 (z=0.130), with a focus on its gamma-ray emission from 100 MeV to 30 TeV. Multiple strong GeV gamma-ray flares, a long-term increase in the gamma-ray and optical flux baseline and a linear correlation between these two bands are observed over the ten-year period. Typical HBL behaviors are identified in the radio morphology and broadband spectrum of the source. Three stationary features in the innermost jet are resolved by VLBA at 43.1, 22.2, and 15.3 GHz. We employ a two-component synchrotron self-Compton model to describe different flux states of the source, including the epoch during which an extreme shift in energy of the synchrotron peak frequency from infrared to soft X-rays is observed
In-situ analysis of continuous cooling precipitation in Al alloys by wide-angle X-ray scattering
No full textThe aim of this work is to investigate quench induced precipitation during continuous coolingin aluminium wrought alloys EN AW-7150 and EN AW-6082 using in situ synchrotron wideangleX-ray scattering (WAXS). While X-ray diffraction is usually an ex situ method, a variety ofdiffraction patterns were recorded during the cooling process, allowing in situ analysis of theprecipitation process. The high beam energy of about 100 keV allows the beam to penetratea bulk sample with a 4 mm diameter in a quenching dilatometer. Additionally, the highintensity of a synchrotron source enables sufficiently high time resolution for fast in situ coolingexperiments. Reaction peaks could be detected and compared with results from differentialscanning calorimetry (DSC) by this method. A methodology is presented in this paper toevaluate WAXS data in a way that is directly comparable to DSC-experiments. The resultsshow a high correlation between both techniques, DSC and WAXS, and can significantlyimprove continuous cooling precipitation diagrams
Higgs inflation in metric and Palatini formalisms: required suppression of higher dimensional operators
No full textWe investigate the sensitivity of Higgs(-like) inflation to higher dimensional operators in the nonminimal couplings and in the potential, both in the metric and Palatini formalisms. We find that, while inflationary predictions are relatively stable against the higher dimensional operators around the attractor point in the metric formalism, they are extremely sensitive in the Palatini one: for the latter, inflationary predictions are spoiled by |ξ4| ≳ 10−6 in the nonminimal couplings (ξ2 φ2 + ξ4 φ4 + &cdots;)R, or by |λ6| ≳ 10−16 in the Jordan-frame potential λ4 φ4 + λ6 φ6 + &cdots; (both in Planck units). This extreme sensitivity results from the absence of attractor in the Palatini formalism. Our study underscores the challenge of realizing inflationary models with the nonminimal coupling in the Palatini formalism