Conveners
QCD and New Physics: E1a
- Marco Gersabeck (University of Manchester (GB))
QCD and New Physics: E1b
- Marco Gersabeck (University of Manchester (GB))
QCD and New Physics: E2a
- Felipe J. Llanes-Estrada
QCD and New Physics: E2b
- William Detmold (Massachusetts Institute of Technology)
QCD and New Physics: E3a
- Felipe J. Llanes-Estrada
QCD and New Physics: E3b
- Massimiliano Procura (University of Vienna (AT))
QCD and New Physics: E5b
- Evgeny Epelbaum (Ruhr-University Bochum)
Rare kaon decays belong to the class of flavour changing neutral current decays and are forbidden at leading order in the Standard Model. For this reason, these decays constitute attractive channels to look for new physics. The NA62 experiment (CERN) is starting this year to measure rare kaon decay amplitudes and it is important to have precise predictions of these quantities in the Standard...
In 1988 the NA31 experiment presented the first evidence of direct CP violation in the $K^0\to\pi\pi$ decay amplitudes. A clear signal with a $7.2\,\sigma$ statistical significance was later established with the full data samples from the NA31, E731, NA48 and KTeV experiments, confirming that CP violation is associated with a $\Delta S=1$ quark transition, as predicted by the Standard Model....
New results in kaon physics from the NA62 experiment at CERN are presented, including the measurement of the K+ --> pi+ nu nu decay rate. NA62 short-term prospects and on-going analyses, including radiative kaon decay measurements and searches lepton number violation, are discussed. Finally, recent results on rare kaon decays from the NA48/2 experiment at CERN are presented.
I will review recent development in the theoretical descriptions of exclusive
rare B-meson decays. These developments have the potential to remove one source of
theoretical systematic uncertainties, which are presently the biggest roadblock
to our understanding of the present bโsโโ anomalies.
The LHCb collaboration has measured several observables in the B sector which show consistent deviations from the Standard Model predictions. B decay anomalies are mainly related to lepton flavour universality and angular observables in flavour-changing-neutral-current transitions. In this talk I will present recent results which are key to enlighten new physics scenarios
EDM of the nucleon, whether observed or further constrained, can be traced back to various CP-violating quark and gluon effective interactions. In order to constrain these effective interactions and, subsequently, the extensions of the Standard Model, nonperturbative calculations of nucleon structure are necessary. Low-energy theories and nucleon models provide ballpark estimates for the nEDM...
The quest for a non-zero electric dipole moment (EDM) in a non-degenerate system such as the neutron is a powerful way to search for physics beyond the standard model in the CP violation framework, complementary to LHC based experiments. So far, no evidence for such an intrinsic property was observed, neither for the neutron nor for any other system. After a long and successful data taking at...
Among the parameters of QCD is one that results in CP violation when
non-vanishing. This is closely related to possible quark mass terms.
It is conventionally interpreted in terms of gauge field topology or
alternatively in terms of real chiral eigenvalues of the Dirac
operator. There is no experimental evidence for this parameter having
a non-zero value, a puzzle for theories involving unification.
In this talk I review recent progress in the determination of the parton distribution functions (PDFs) of the proton, with emphasis on the applications for precision phenomenology and of searches for new physics beyond the Standard Model at the Large Hadron Collider (LHC). I discuss the number of recent developements such as the use of novel observables such as top quark pair production and...
We present non-perturbative first-principle results for quark-, gluon- and meson 1PI correlation functions of two-flavour Landau-gauge QCD in the vacuum [1] and Yang-Mills theory at finite temperature [2]. These correlation functions carry the full information about the theory and their connection to physical observables is discussed. We confront our results for the correlation functions with...
Chiral effective field theory has been developed into a reliable, qiantitative approach to low-energy few- and many-nucleon systems. I will review the current status of nuclear forces in this framework and discuss selected applications to light nuclei and nuclear matter. Special emphasis will be given to uncertainty quantification.
I will discuss recent lattice QCD calculations that constrain aspects of neutrino-nucleon and neutrino-nucleus interactions. In particular, I will show results for axial charges and form factors of the nucleon and of nuclei, constraints of tritium beta decay, and input for neutrinoful and neutrinoless double beta decay.
A possible explanation of dark matter is the existence of an unobserved massive particle. The mass range and the interaction rate with ordinary matter extend over several orders of magnitude. Different detector technologies will be required in order to reach the necessary sensitivity. The CRESST III experiment (Cryogenic Rare Event Search with Superconducting Thermometers) is best suited to...
We present a formalism based on chiral effective field theory that incorporates all coherent responses relevant for the analysis of direct-detection dark-matter searches. The nuclear response functions are derived, including contributions from one- and two-body nuclear currents as well as interference terms between the different channels. The corresponding structure factors for the isotopes...
The Standard Model provides the current best description of fundamental particles and forces, but among other limitations it fails to account for dark matter which could manifest itself as more massive particles. Precision measurements of well predicted observables in the Standard Model allow for highly targeted tests for physics beyond the Standard Model. The Qweak experiment at Jefferson Lab...
We report the first observation of the parity-violating $2.2$ MeV gamma-ray asymmetry $A^{np}_{\gamma}$, in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target, at the Spallation Neutron Source at Oak Ridge National Laboratory. The asymmetry isolates the long-range component of the hadronic weak interaction, corresponding to the $ \Delta I = 1$, $^3S_1...
The talk will describe the g-2 experiment based at Fermilab.
As the experiment enters an exciting period of data taking
and analysis, the current status and future prospects will be
highlighted.
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impressive accuracy of 0.54 parts per million reached...
This talk reviews recent theoretical developments in the study of charged lepton flavour violation. It describes the recent progress in the effective field theory interpretation of charged lepton-flavour violating observables in connection with different energy scales by exploiting the SMEFT framework. A systematic approach is briefly presented and applications on muonic and tauonic...
The CMD-3 detector is taking data at the VEPP-2000 e+e-
collider (BINP, Novosibirsk, Russia). The CMD-3
is the general purpose particle magnetic (1.3 T) detector, equipped with
the tracking system, two crystal (CSI and BGO) calorimeters, liquid Xe
calorimeter, TOF and muon systems. The main goal of experiments with CMD-3
is the measurement of the cross-sections and dynamics of the...
Lund diagrams, a representation of the phase space within jets, have long been used in discussing parton showers and resummations. I will point out that they can also serve as a powerful tool for experimentally characterising the radiation pattern within jets. I will briefly comment on some of their analytical properties and highlight their scope for constraining Monte Carlo simulations. I...
The high energy scale of the LHC and the large associated Lorentz boost of hadronically decaying massive particles has resulted in the creation of a new approach to jet identification. Jet substructure, or the use of angular and energy distributions within jets, has proven to be a powerful means of differentiating between hadronic decays of massive particles and QCD multijets production. ...
A model based on CGC/Saturation approach and the BFKL Pomeron was originally constructed to describe soft interactions at LHC energies [reference (a)]. It has now been extended to also describe hard interactions at HERA energies [reference (b)]. The model also provides a good description of inclusive production, rapidity and angular correlations over a wide range of energies. We outline the...
We study $4$-dimensional SQCD with gauge group $SU(N_c)$ and $N_f$ flavors of chiral super-multiplets on the lattice. We perform extensive calculations of matrix elements and renormalization factors of composite operators in Perturbation Theory. In particular, we compute the renormalization factors of quark and squark bilinears, as well as their mixing at the quantum level with gluino and...
We have measured several 2S-2P transitions in muonic hydrogen ($\mu$p), muonic deuterium ($\mu$d) and muonic helium ions ($\mu^3$He, $\mu^4$He). From muonic hydrogen we extracted a proton charge radius 20 times more precise than obtained from electron-proton scattering and hydrogen high-precision laser spectroscopy but at a variance of $7\sigma$ from these values. This discrepancy is...
The allowed window on new physics to emerge from low-energy precision measurements of hadronic properties and processes relies on theoretical input as well. I review how recent progress in the analysis and computation of baryon matrix elements impact the interpretation of current, planned, and possible experiments in neutron beta decay and searches for neutron-antineutron conversion.
Potential detection of non-conserving lepton number processes, such as the neutrinoless double beta decay, constitutes one of the most promising signals of new physics beyond the Standard Model, apart from experiments using high energy collisions. In the neutrinoless double beta decay (0ฮฝฮฒฮฒ) two neutrons are transformed into two protons and only two electrons are emitted in the final state....
The search of neutrinoless double-beta decay plays a fundamental role in the understanding of neutrino physics. Its observation would prove that neutrinos are Majorana particles and that lepton number is not conserved, with a profound impact on elementary particle physics, nuclear physics, astrophysics, and cosmology. Experiments presently running will cover the quasi-degeneracy region of the...