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Calculations for deep inelastic scattering using fast interpolation grid techniques at NNLO in QCD and the extraction of $\alpha_s$ from HERA data
http://cds.cern.ch/record/2678552
The extension of interpolation-grid frameworks for perturbative QCD calculations at next-to-next-to-leading order (NNLO) is presented for deep inelastic scattering (DIS) processes. A fast and flexible evaluation of higher-order predictions for any a posteriori choice of parton distribution functions (PDFs) or value of the strong coupling constant is essential in iterative fitting procedures to extract PDFs and Standard Model parameters as well as for a detailed study of the scale dependence. The APPLfast project, described here, provides a generic interface between the parton-level Monte Carlo program NNLOJET and both the APPLgrid and fastNLO libraries for the production of interpolation grids at NNLO accuracy. Details of the interface for DIS processes are presented together with the required interpolation grids at NNLO, which are made available. They cover numerous inclusive jet measurements by the H1 and ZEUS experiments at HERA. An extraction of the strong coupling constant is performed as an application of the use of such grids and a best-fit value of $\alpha_s(M_Z) = 0.1170\,(15)_\text{exp}\,(25)_\text{th}$ is obtained using the HERA inclusive jet cross section data.Britzger, D.Currie, J.Gehrmann-De Ridder, A.Gehrmann, T.Glover, E.W.N.Gwenlan, C.Huss, A.Morgan, T.Niehues, J.Pires, J.Rabbertz, K.Sutton, M.R.Sat, 15 Jun 2019 03:00:44 GMT2019-06-12arXiv:1906.05303http://cds.cern.ch/record/2678552['arXiv:1906.05303']arXiv:1906.05303Constraining primordial black hole masses with the isotropic gamma ray background
http://cds.cern.ch/record/2678422
Primordial black holes can represent all or most of the dark matter in the window $10^{17}-10^{22}\,$g. Here we present an extension of the constraints on PBHs of masses $10^{13}-10^{18}\,$g arising from the isotropic diffuse gamma ray background. Primordial black holes evaporate by emitting Hawking radiation that should not exceed the observed background. Generalizing from monochromatic distributions of Schwarzschild black holes to extended mass functions of Kerr rotating black holes, we show that the lower part of this mass window can be closed for near-extremal black holes.Arbey, AlexandreAuffinger, JérémySilk, JosephFri, 14 Jun 2019 02:02:42 GMT2019-06-11arXiv:1906.04750http://cds.cern.ch/record/2678422['arXiv:1906.04750']arXiv:1906.04750A Monte-Carlo Simulation of Double Parton Scattering
http://cds.cern.ch/record/2678274
In this work, a new Monte-Carlo simulation of double parton scattering (DPS) at parton level is presented. The simulation is based on the QCD framework developed recently by M. Diehl, J. R. Gaunt and K. Sch\"{o}nwald. With this framework, the dynamics of the $1\to2$ perturbative splittings is consistently included inside the simulation, with the impact-parameter dependence taken into account. The simulation evolves simultaneously two hard systems from a common hard scale down to the hadronic scale. The evolution is performed using an angular-ordered parton shower which is combined with a set of double parton distributions that depend explicitly on the inter-parton distance. An illustrative study is performed in the context of same-sign WW production at the LHC, with the quark content of the proton being limited to three flavours. In several distributions we see differences compared to DPS models in Herwig, Pythia, and the DPS "pocket formula".Cabouat, BaptisteGaunt, Jonathan R.Ostrolenk, KiranThu, 13 Jun 2019 03:06:41 GMT2019-06-11arXiv:1906.04669http://cds.cern.ch/record/2678274['arXiv:1906.04669']arXiv:1906.04669Any extremal black holes are primordial
http://cds.cern.ch/record/2678273
Extremal Kerr black holes, if they exist, cannot have an astrophysical origin due to the Thorne limit $a<a^*_{\rm lim}=0.998$. However this limit can be evaded if they are primordial and subject to evaporation by Hawking radiation. We derive the lower mass limit above which Hawking radiation is slow enough so that a primordial black hole with a spin initially above the Thorne limit can still be above this limit today. Thus, the observation of a Kerr black hole with $a^* > a^*_{\rm lim}$ should be a proof of its primordial origin.Arbey, AlexandreAuffinger, JérémySilk, JosephThu, 13 Jun 2019 03:06:39 GMT2019-06-10arXiv:1906.04196http://cds.cern.ch/record/2678273['arXiv:1906.04196']arXiv:1906.04196Hořava gravity: motivation and status
http://cds.cern.ch/record/2678068
In this short contribution, I will review the status of Hořava gravity as a proposal for quantum gravity. After summarizing the framework and phenomenological constraints, I will present some recent work on the renormalization group flow in 2 + 1 dimensions. The main result is that the theory is asymptotically free and flows to an infrared fixed point connected to a Lorentz-invariant theory.Blas, DiegoWed, 12 Jun 2019 04:17:18 GMThttp://cds.cern.ch/record/2678068['']Physical projectors for multi-leg helicity amplitudes
http://cds.cern.ch/record/2678047
We present a method for building physical projector operators for multi-leg helicity amplitudes. For any helicity configuration of the external particles, we define a physical projector which singles out the corresponding helicity amplitude. For processes with more than four external legs, these physical projectors depend on significantly fewer tensor structures and exhibit a remarkable simplicity compared with projector operators defined with traditional approaches. As an example, we present analytic formulas for a complete set of projectors for five-gluon scattering. These have been validated by reproducing known results for five-gluon amplitudes up to one-loop.Peraro, TizianoTancredi, LorenzoWed, 12 Jun 2019 02:32:47 GMT2019-06-07arXiv:1906.03298http://cds.cern.ch/record/2678047['arXiv:1906.03298']arXiv:1906.03298Non-perturbative determination of improvement coefficients b_m and b_A-b_P and normalisation factor Z_m*Z_P/Z_A with N_f=3 Wilson fermions
http://cds.cern.ch/record/2678046
We non-perturbatively determine the normalisation constant Z_m*Z_P/Z_A as well as the Symanzik coefficients b_m and b_A-b_P, required in O(a) improved quark mass renormalisation with Wilson fermions. The strategy underlying their computation involves simulations in N_f=3 QCD with O(a) improved massless sea and non-degenerate valence quarks in the finite-volume Schroedinger functional scheme. Our results, which cover the typical gauge coupling range of large-volume N_f=2+1 QCD simulations with Wilson fermions at lattice spacings below 0.1 fm, are of particular use for the non-perturbative calculation of O(a) improved renormalised quark masses.de Divitiis, Giulia MariaFritzsch, PatrickHeitger, JochenKoester, Carl ChristianKuberski, SimonVladikas, AnastassiosWed, 12 Jun 2019 02:32:44 GMT2019-06-08arXiv:1906.03445http://cds.cern.ch/record/2678046['arXiv:1906.03445']arXiv:1906.03445A maximal-entropy initial state of the Universe as a microscopic description of inflation
http://cds.cern.ch/record/2677488
We propose that the initial state of the Universe was an isotropic state of maximal entropy. Such a state can be described in terms of a state of closed, interacting, fundamental strings in their high-temperature Hagedorn phase. The entropy density in this state is equal to the square root of the energy density in Planck units, while the pressure is positive and equal to the energy density. These relations imply a maximally large entropy density and, therefore, a state that cannot be described by a semiclassical spacetime geometry. If one nevertheless insists on an effective semiclassical description of this state, she can do so by ignoring the entropy. This leads to a partially equivalent description in which the pressure appears to be negative and equal in magnitude to the energy density, as if the energy-momentum tensor was that of a cosmological constant. From this effective perspective, the state describes a period of string-scale inflation. The bound state of strings ultimately decays, possibly by a process akin to Hawking radiation, and undergoes a transition into a phase of hot radiation. But, from the effective perspective, the same decay corresponds to the heating of the Universe at the end of inflation. Small quantum mechanical fluctuations in the initial state lead to scale-invariant temperature anisotropies in the hot radiation. The temperature anisotropies are interpreted in the effective description as arising from quantum fluctuations of the curvature and an effective inflaton field. The stringy microscopic description determines the parameters of the model of inflation, as well as the cosmological observables, in terms of the string length scale and coupling strength. Our framework is similar, conceptually, to a recent description of black holes in terms of a maximal entropy state of strings in the Hagedorn phase.Brustein, RamMedved, A.J.M.Thu, 06 Jun 2019 02:05:43 GMT2019-06-03arXiv:1906.00989http://cds.cern.ch/record/2677488['arXiv:1906.00989']arXiv:1906.00989Fiducial cross sections for the four-lepton decay mode in Higgs-plus-jet production up to NNLO QCD
http://cds.cern.ch/record/2677206
The four-lepton decay mode of the Higgs boson allows for a clean kinematic reconstruction, thereby enabling precision studies of the Higgs boson properties and of its production dynamics. We compute the NNLO QCD corrections to fiducial cross sections relevant to this decay mode in the gluon-fusion production of a Higgs boson in association with a hadronic jet, and study the impact of the QCD corrections on the fiducial acceptance factors in inclusive Higgs and Higgs-plus-jet production. We investigate in detail the different definitions used in the ATLAS and CMS measurements to define the fiducial cross sections. Differences in the lepton isolation prescription are found to have a sizeable impact on the higher order corrections to the fiducial acceptance factors.Chen, X.Gehrmann, T.Glover, E.W.N.Huss, A.Tue, 04 Jun 2019 02:04:34 GMT2019-05-31arXiv:1905.13738http://cds.cern.ch/record/2677206['arXiv:1905.13738']arXiv:1905.13738Looking for ultralight dark matter near supermassive black holes
http://cds.cern.ch/record/2676801
Measurements of the dynamical environment of supermassive black holes (SMBHs) are becoming abundant and precise. We use such measurements to look for ultralight dark matter (ULDM), which is predicted to form dense cores ("solitons") in the centre of galactic halos. We search for the gravitational imprint of an ULDM soliton on stellar orbits near Sgr A* and by combining stellar velocity measurements with Event Horizon Telescope imaging of M87*. Finding no positive evidence, we set limits on the soliton mass for different values of the ULDM particle mass $m$. The constraints we derive exclude the solitons predicted by a naive extrapolation of the soliton-halo relation, found in DM-only numerical simulations, for $3\times10^{-20}~{\rm eV}\lesssim m\lesssim8\times10^{-19}~{\rm eV}$ (from Sgr A*) and $m\lesssim4\times10^{-22}~{\rm eV}$ (from M87*). However, we present theoretical arguments suggesting that an extrapolation of the soliton-halo relation may not be adequate: in some regions of the parameter space, the dynamical effect of the SMBH could cause this extrapolation to over-predict the soliton mass by orders of magnitude.Bar, NitsanBlum, KfirLacroix, ThomasPanci, PaoloThu, 30 May 2019 02:08:31 GMT2019-05-28arXiv:1905.11745http://cds.cern.ch/record/2676801['arXiv:1905.11745']arXiv:1905.11745The transverse momentum spectrum of weak gauge bosons at N$^3$LL$+$NNLO
http://cds.cern.ch/record/2676693
We present accurate QCD predictions for the transverse momentum pT spectrum of electroweak gauge bosons at the LHC for 13 TeV collisions, based on a consistent combination of a NNLO calculation at large pT and N3LL resummation in the small pT limit. The inclusion of higher order corrections leads to substantial changes in the shape of the differential distributions, and the residual perturbative uncertainties are reduced to the few percent level across the whole transverse momentum spectrum. We examine the ratio of pT distributions in charged- and neutral-current Drell-Yan production, and study different prescriptions for the estimate of perturbative uncertainties that rely on different degrees of correlation between these processes. We observe an excellent stability of the ratios with respect to the perturbative order, indicating a strong correlation between the corresponding QCD corrections.Bizon, WojciechGehrmann-De Ridder, AudeGlover, NigelHuss, AlexanderMonni, Pier FrancescoRe, EmanueleRottoli, LucaWalker, Duncan M.Wed, 29 May 2019 02:38:27 GMT2019-05-13arXiv:1905.05171http://cds.cern.ch/record/2676693['arXiv:1905.05171']arXiv:1905.05171Towards the renormalization group flow of Horava gravity in $(3+1)$ dimensions
http://cds.cern.ch/record/2676559
We compute the renormalization group running of the Newton constant and the parameter $\lambda$ in $(3+1)$-dimensional projectable Horava gravity. We use the background field method expanding around configurations with flat spatial metric, but non-vanishing shift. This allows us to reduce the number of interaction vertices and thereby drastically simplify the calculations. The gauge invariant $\beta$-function of $\lambda$ has two families of zeros, attractive in the infrared and ultraviolet respectively. They are candidates for the fixed points of the full renormalization group flow of the theory, once the $\beta$-functions for the rest of the couplings are added.Barvinsky, Andrei O.Herrero-Valea, MarioSibiryakov, Sergey M.Tue, 28 May 2019 02:02:33 GMT2019-05-09arXiv:1905.03798http://cds.cern.ch/record/2676559['arXiv:1905.03798']arXiv:1905.03798The triple differential di-jet cross section at the LHC
http://cds.cern.ch/record/2676121
The measurement of the triple-differential di-jet production cross section as function of the average transverse momentum $p_{T,\textrm{avg}}$, half the rapidity separation $y^{*}$, and the boost $y_{b}$ of the two leading jets in the event enables a kinematical scan of the underlying parton momentum distributions. We compute for the first time the second-order perturbative QCD corrections to this triple-differential di-jet cross section, at leading colour in all partonic channels, thereby enabling precision studies with LHC di-jet data. A detailed comparison with experimental CMS 8 TeV data is performed, demonstrating how the shape of this differential cross section probes the parton densities in different kinematical ranges.Gehrmann-De Ridder, A.Gehrmann, T.Glover, E.W.N.Huss, A.Pires, J.Fri, 24 May 2019 02:02:55 GMT2019-05-22arXiv:1905.09047http://cds.cern.ch/record/2676121['arXiv:1905.09047']arXiv:1905.09047Sterile neutrino dark matter via GeV-scale leptogenesis?
http://cds.cern.ch/record/2676120
It has been proposed that in a part of the parameter space of the Standard Model completed by three generations of keV...GeV right-handed neutrinos, neutrino masses, dark matter, and baryon asymmetry can be accounted for simultaneously. Here we numerically solve the evolution equations describing the cosmology of this scenario in a 1+2 flavour situation at temperatures $T \le 5$ GeV, taking as initial conditions maximal lepton asymmetries produced dynamically at higher temperatures, and accounting for late entropy and lepton asymmetry production as the heavy flavours fall out of equilibrium and decay. For 7 keV dark matter mass and other parameters tuned favourably, $\sim 10\%$ of the observed abundance can be generated. Possibilities for increasing the abundance are enumerated.Ghiglieri, J.Laine, M.Fri, 24 May 2019 02:02:49 GMT2019-05-21arXiv:1905.08814http://cds.cern.ch/record/2676120['arXiv:1905.08814']arXiv:1905.08814Black holes in the quantum universe
http://cds.cern.ch/record/2676119
A succinct summary is given of the problem of reconciling observation of black hole-like objects with quantum mechanics. If quantum black holes behave like subsystems, and also decay, their information must be transferred to their environments. Interactions that accomplish this with `minimal' departure from a standard description are parameterized. Possible sensitivity of gravitational wave or very long baseline interferometric observations to these interactions is briefly outlined.Giddings, Steven B.Fri, 24 May 2019 02:02:48 GMT2019-05-21arXiv:1905.08807http://cds.cern.ch/record/2676119['arXiv:1905.08807']arXiv:1905.08807CONSTITUENT QUARKS AND CURRENT QUARKS
http://cds.cern.ch/record/2675303
Weyers, JTue, 21 May 2019 04:34:08 GMT1973http://cds.cern.ch/record/2675303['']Direct Detection of Strongly Interacting Sub-GeV Dark Matter via Electron Recoils
http://cds.cern.ch/record/2674984
We consider direct-detection searches for sub-GeV dark matter via electron scatterings in the presence of large interactions between dark and ordinary matter. Scatterings both on electrons and nuclei in the Earth's crust, atmosphere, and shielding material attenuate the expected local dark matter flux at a terrestrial detector, so that such experiments lose sensitivity to dark matter above some critical cross section. We study various models, including dark matter interacting with a heavy and ultralight dark photon, through an electric dipole moment, and exclusively with electrons. For a dark-photon mediator and an electric dipole interaction, the dark matter-electron scattering cross-section is directly linked to the dark matter-nucleus cross section, and nuclear interactions typically dominate the attenuation process. We determine the exclusion bands for the different dark-matter models from several experiments - SENSEI, CDMS-HVeV, XENON10, XENON100, and DarkSide-50 - using a combination of Monte Carlo simulations and analytic estimates. We also derive projected sensitivities for a detector located at different depths and for a range of exposures, and calculate the projected sensitivity for SENSEI at SNOLAB and DAMIC-M at Modane. Finally, we discuss the reach to high cross sections and the modulation signature of a small balloon- and satellite-borne detector sensitive to electron recoils, such as a Skipper-CCD. Such a detector could potentially probe unconstrained parameter space at high cross sections for a sub-dominant component of dark matter interacting with a massive, but ultralight, dark photon.Emken, TimonEssig, RouvenKouvaris, ChrisSholapurkar, MukulSat, 18 May 2019 02:03:03 GMT2019-05-15arXiv:1905.06348http://cds.cern.ch/record/2674984['arXiv:1905.06348']arXiv:1905.06348TASI lectures on Future Colliders
http://cds.cern.ch/record/2674965
These lectures review the main motivations for future high-energy colliders, focusing on the understanding of electroweak symmetry breaking and on the search for physics beyond the Standard Model. The open questions and the challenges are common to all future projects; for concreteness, I will use studies of the potential of e+e– and pp circular colliders to provide examples of the anticipated physics reach.Mangano, MichelangeloFri, 17 May 2019 21:02:13 GMT17 May 2019arXiv:1905.07489http://cds.cern.ch/record/2674965['arXiv:1905.07489']arXiv:1905.07489Theory report on the 11th FCC-ee workshop
http://cds.cern.ch/record/2674514
The FCC at CERN, a proposed 100-km circular facility with several colliders in succession, culminates with a 100 TeV proton-proton collider. It offers a vast new domain of exploration in particle physics, with orders of magnitude advances in terms of Precision, Sensitivity and Energy. The implementation plan foresees, as a first step, an Electroweak Factory electron-positron collider. This high luminosity facility, operating between 90 and 365 GeV centre-of-mass energy, will study the heavy particles of the Standard Model, Z, W, Higgs, and top with unprecedented accuracy. The Electroweak Factory $e^+e^-$ collider constitutes a real challenge to the theory and to precision calculations, triggering the need for the development of new mathematical methods and software tools. A first workshop in 2018 had focused on the first FCC-ee stage, the Tera-Z, and confronted the theoretical status of precision Standard Model calculations on the Z-boson resonance to the experimental demands. The second workshop in January 2019, which is reported here, extended the scope to the next stages, with the production of W-bosons (FCC-ee-W), the Higgs boson (FCC-ee-H) and top quarks (FCC-ee-tt). In particular, the theoretical precision in the determination of the crucial input parameters, alpha_QED, alpha_QCD, M_W, m_t at the level of FCC-ee requirements is thoroughly discussed. The requirements on Standard Model theory calculations were spelled out, so as to meet the demanding accuracy of the FCC-ee experimental potential. The discussion of innovative methods and tools for multi-loop calculations was deepened. Furthermore, phenomenological analyses beyond the Standard Model were discussed, in particular the effective theory approaches.Blondel, A.Gluza, J.Jadach, S.Janot, P.Riemann, T.Wed, 15 May 2019 02:18:10 GMT2019-05-13arXiv:1905.05078http://cds.cern.ch/record/2674514['arXiv:1905.05078']arXiv:1905.05078Flow in AA and pA as an interplay of fluid-like and non-fluid like excitations
http://cds.cern.ch/record/2674513
To study the microscopic structure of quark-gluon plasma, data from hadronic collisions must be confronted with models that go beyond fluid dynamics. Here, we study a simple kinetic theory model that encompasses fluid dynamics but contains also particle-like excitations in a boost invariant setting with no symmetries in the transverse plane and with large initial momentum asymmetries. We determine the relative weight of fluid dynamical and particle like excitations as a function of system size and energy density by comparing kinetic transport to results from the 0th, 1st and 2nd order gradient expansion of viscous fluid dynamics. We then confront this kinetic theory with data on azimuthal flow coefficients over a wide centrality range in PbPb collisions at the LHC, in AuAu collisions at RHIC, and in pPb collisions at the LHC. Evidence is presented that non-hydrodynamic excitations make the dominant contribution to collective flow signals in pPb collisions at the LHC and contribute significantly to flow in peripheral nucleus-nucleus collisions, while fluid-like excitations dominate collectivity in central nucleus-nucleus collisions at collider energies.Kurkela, AleksiWiedemann, Urs AchimWu, BinWed, 15 May 2019 02:17:43 GMT2019-05-13arXiv:1905.05139http://cds.cern.ch/record/2674513['arXiv:1905.05139']arXiv:1905.05139BlackHawk: A public code for calculating the Hawking evaporation spectra of any black hole distribution
http://cds.cern.ch/record/2674326
We describe BlackHawk, a public C program for calculating the Hawking evaporation spectra of any black hole distribution. This program enables the users to compute the primary and secondary spectra of stable or long-lived particles generated by Hawking radiation of the distribution of black holes, and to study their evolution in time. The physics of Hawking radiation is presented, and the capabilities, features and usage of BlackHawk are described here under the form of a manual.Arbey, AlexandreAuffinger, JérémyTue, 14 May 2019 02:01:56 GMT2019-05-10arXiv:1905.04268http://cds.cern.ch/record/2674326['arXiv:1905.04268']arXiv:1905.04268Hypercharged Naturalness
http://cds.cern.ch/record/2673777
We present an exceptional twin-Higgs model with the minimal symmetry structure for an exact implementation of twin parity along with custodial symmetry. Twin particles are mirrors of the Standard Model yet they carry hypercharge, while the photon is identified with its twin. We thoroughly explore the phenomenological signatures of hypercharged naturalness: long-lived charged particles, a colorless twin top with electric charge $2/3$ that once pair-produced, bounds via twin-color interactions and can annihilate to dileptons or a Higgs plus a photon or a $Z$, and glueballs produced from Higgs decays and twin-quarkonium annihilation that either decay displaced, or are stable on collider scales and eventually decay to diphotons. Prospects for detection of these signatures are also discussed.Serra, JaviStelzl, StefanTorre, RiccardoWeiler, AndreasThu, 09 May 2019 02:45:59 GMT2019-05-06arXiv:1905.02203http://cds.cern.ch/record/2673777['arXiv:1905.02203']arXiv:1905.02203The light-ray OPE and conformal colliders
http://cds.cern.ch/record/2673645
We derive a nonperturbative, convergent operator product expansion (OPE) for null-integrated operators on the same null plane in a CFT. The objects appearing in the expansion are light-ray operators with fixed spin and bounded transverse spin, whose matrix elements can be computed by the generalized Lorentzian inversion formula. For example, a product of average null energy (ANEC) operators has an expansion in spin-3 light-ray operators. An important application is to collider event shapes. The light-ray OPE gives a nonperturbative expansion for event shapes in special functions that we call celestial blocks. As an example, we apply the celestial block expansion to energy-energy correlators in N=4 Super Yang-Mills theory. Using known OPE data, we find perfect agreement with previous results both at weak and strong coupling, and make new predictions at weak coupling through 4 loops (NNNLO).Kologlu, MuratKravchuk, PetrSimmons-Duffin, DavidZhiboedov, AlexanderWed, 08 May 2019 02:38:21 GMT2019-05-03arXiv:1905.01311http://cds.cern.ch/record/2673645['arXiv:1905.01311']arXiv:1905.01311Resummation of Boson-Jet Correlation at Hadron Colliders
http://cds.cern.ch/record/2673644
We perform a precise calculation of the transverse momentum ($\vec{q}_T$) distribution of the boson+jet system in boson production events. The boson can be either a photon, $W$, $Z$ or Higgs boson with mass $m_V$, and $\vec{q}_T$ is the sum of the transverse momenta of the boson and the leading jet with magnitude $q_T=|\vec q_T|$. Using renormalization group techniques and soft-collinear effective theory, we resum logarithms $\log(Q/q_T)$ and $\log R$ at next-to-leading logarithmic accuracy including the non-global logarithms, where $Q$ and $R$ are respectively the hard scattering energy and the radius of the jet. Specifically, we investigate two scenarios of $p^J_T \lesssim m_V$ or $p^J_T \gtrsim m_V$ in $Z$+jet events, and we examine the $q_T$ distributions with different jet radii and study the effect of non-global logarithms. In the end we compare our theoretical calculations with Monte Carlo simulations and data from the LHC.Chien, Yang-TingShao, Ding YuWu, BinWed, 08 May 2019 02:38:14 GMT2019-05-03arXiv:1905.01335http://cds.cern.ch/record/2673644['arXiv:1905.01335']arXiv:1905.01335Effective Theories for Quark Flavour Physics
http://cds.cern.ch/record/2673326
The purpose of these lectures is to provide the reader with an idea of how we can probe New Physics with quark flavour observables using effective theory techniques. After giving a concise review of the quark flavour structure of the Standard Model, we introduce the effective Hamiltonian for quark weak decays. We then consider the effective Hamiltonian for $\Delta F=2$ transitions in the Standard Model and beyond. We discuss how meson-antimeson mixing and CP violation can be described in terms of the $\Delta F=1$ and $\Delta F=2$ effective Hamiltonians. Finally we present the Unitarity Triangle Analysis and discuss how very stringent constraints on New Physics can be obtained from $\Delta F=2$ processes.Silvestrini, LucaSat, 04 May 2019 02:45:24 GMT2019-05-02arXiv:1905.00798http://cds.cern.ch/record/2673326['arXiv:1905.00798']arXiv:1905.00798