Conveners
Quark and charged lepton flavour: 1
- Christine Davies
Quark and charged lepton flavour: Poster session
- There are no conveners in this block
Quark and charged lepton flavour: 2
- Marie-Helene Schune (Université Paris-Saclay (FR))
Quark and charged lepton flavour: Parallel 1
- Patrick Koppenburg (Nikhef National institute for subatomic physics (NL))
Quark and charged lepton flavour: Parallel 2
- Alexey Petrov (Wayne State University)
Quark and charged lepton flavour: Parallel 3
- Xiaoyan Shen (University of Science and Technology of China (CN))
Quark and charged lepton flavour: Parallel 4
- Stefan Schacht (University of Manchester)
New physics (NP) models with additional CP violation sources are heavily constrained by the experimental limits on permanent electric dipole moments (EDMs) of particles. Using the stringent limits on their chromo-EDMs, new bounds on the EDM of charm and bottom quarks are derived. The new limits improve the previous ones by about three orders of magnitude. The implications for different NP...
The NA62 experiment at CERN collected a large sample of charged kaon decays into final states with multiple charged particles in 2016-2018. This sample provides sensitivities to rare decays with branching ratios as low as 10-11.
Results from searches for lepton flavour/number violating decays of the charged kaon and the neutral pion to final states containing a lepton pair based on this data...
We study $\Lambda_b\to (\Lambda^*, \Lambda){\mu}^{+}\mu^{-}$ and $\Lambda_b\to (\Lambda^*, \Lambda) \nu\bar{\nu}$ baryonic decays undergoing $b\to s \ell^{+}\ell^{-}$ and $b\to s\nu\bar{\nu}$ neutral transitions in a standard model effective field theory formalism. The $b\to s l^{+}l^{-}$ and $b\to s\nu\bar{\nu}$ transition decays are related in beyond the Standard Model physics by $SU(2)_L$...
Applying an operator product expansion approach an updated Standard Model prediction of the Bc lifetime will be presented. The non-perturbative velocity expansion is carried out up to third order in the relative velocity of the heavy quarks. Scheme dependence is studied using three different mass schemes for the b and c quarks, resulting in three different values consistent with each other and...
The Heavy Flavor Averaging Group has for the past two decades formed averages of measurements involving the properties of b-hadron, c-hadron and $\tau$ leptons. The averages are taking into account direct as well as indirect measurements of properties and are updating external constraints to include their latest values.
We will in the presentation outline the averaging methodology used and...
Semileptonic flavor changing neutral current transitions with a pair of neutrinos in the final state are very accurately determined in the standard model. The most recent Belle II result on $B\to K \nu \bar\nu$ uses an innovative inclusive tagging technique; this together with previous BaBar and Belle results indicates a possible enhancement in the branching fraction of $B\to K \nu \bar\nu$....
A coherent pattern of deviations from Standard Model predictions has been observed in $b$-hadron decays of the type $b\to s\ell^+\ell^-$. These deviations seem to indicate
the existence of a new fundamental interaction that breaks lepton flavour universality (LFU).
We discuss the Look Elsewhere Effect in estimating the significance
of this hypothesis and, more generally, any new physics...
The semileptonic b-hadron decays with a heavy lepton are sensitive to new couplings like those generated by charged Higgses or Leptoquarks. The B-Factories and LHCb have previously performed various measurements of these decays, using different approaches and techniques. A global average of these measurements shows a discrepancy with the Standard Model expectations, which is above 3 standard...
Decays of B mesons that proceed through electroweak and radiative penguin amplitudes currently attract significant attention due to a number of observed discrepancies between the standard model predictions and the experimental results.
Belle II is expected to perform measurements on channels closely related to those exhibiting anomalies and that are uniquely available to Belle II. These...
The coupling of the electroweak gauge bosons of the Standard Model (SM) to leptons is independent of the lepton flavour. Extensions of the SM do not necessarily respect this lepton flavour universality. Semileptonic rare decays of heavy flavour, to which new particles can give sizeable contributions, allow for sensitive tests of lepton flavour universality, and constitute powerful indirect...
The lepton flavor violation is a clear signature of the new physics and has been searched for by many experiments. Such decays can be searched using large amount of $B$ and $\Upsilon$ mesons produced at Belle. We present our search for $B \to \ell\tau$, $\Upsilon(nS) \to \ell \ell', \ell \tau$ decays (\ell = e, \mu). We also present the final results on $\tau \to \ell \gamma$ at Belle. In...
We perform a data-driven analysis of new physics (NP) effects in exclusive $b \to s \ell^+\ell^-$ decays in a
model-independent effective theory approach with dimension six operators considering scalar, pseudo-scalar,
vector and axial-vector operators with the corresponding Wilson coefficients (WC) taken to be complex. The
analysis has been done with the most recent data while comparing the...
Armed with the Lattice and the most recent inputs from LCSR for the $B\to\pi$ form factors, we revisit the extraction of exclusive $V_{ub}$ from the data on $B\to\pi l\nu$ branching ratios (BR's) from Belle and Babar. We analyze the complete set of available data and comment on the outliers, pointing out the differences between such an analysis and the one done by HFLAV previously using an...
The low-background environment of electron-positron collisions along with the large expected sample size and an hermetic detector make Belle II the premier experiment for studying tau-lepton physics. A competitive measurement of the mass of the tau lepton is reported based on a a small data set, and studies for world-leading measurements of tau lifetimes, foreseen with significantly less data...
The Mu2e experiment will search for the charged lepton flavor violating process of muon-to-electron conversion in the field of an aluminum nucleus. Muon-to-electron conversion is heavily suppressed in the standard model and so an observation of this signal would be a clear sign of new physics. Mu2e will search for the mono-energetic, 105 MeV electron signal with a discovery potential four...
The observation of charged Lepton Flavour Violating (cLFV) processes would be a definitive signature of physics beyond the Standard Model.
The phase I one of the MEG experiment established the best upper limit on the branching ratio of one of the cLFV golden channels, μ →eγ: BR (μ →eγ) < 4.2 ×10-13 (@90% Confidence Level).
This limit will be improved by about one order of magnitude by the...
The NA62 experiment at CERN reports new results from studies of radiative kaon decays K+ → pi0 e+ v gamma (Ke3g), using a data sample recorded in 2017-2018. The sample comprises O(100k) Ke3g candidates with sub-percent background contaminations. Preliminary results with the most precise measurement of the Ke3g branching ratios and T-asymmetry measurement in the Ke3g decay, are presented.
The decay K+→π+ νν ̅, with a very precisely predicted branching ratio of less than 10-10, is among the best processes to reveal indirect effects of new physics.
The NA62 experiment at CERN SPS is designed to study the K+→π+ νν ̅ decay and to measure its branching ratio using a decay-in-flight technique. NA62 took data in 2016, 2017 and 2018, reaching the sensitivity of the Standard Model...
In this talk, I will present the results of a sensitivity study of un-binned angular analysis of $B\to D^* \ell\nu$ decay, including the contributions from the right-handed vector current. I will show that the angular observables can constrain very strongly the right-handed current without the intervention of the yet unsolved Vcb puzzle.
We discuss HPQCD's recent precise determinations of the $D \to K$ and $B \to K$ scalar, vector and tensor form factors from full lattice QCD using the HISQ formalism.
Our $D \to K$ form factors allow us to calculate the differential rate for $D\to K \ell\nu$ with improved precision. Comparison with experimental results gives the CKM element $V_{cs}$ to better than 1\% for the first time:...
Though the Belle experiment has stopped data taking more than a decade ago, new results on semileptonic B meson decays are still being obtained. This is in part due to new experimental tools elaborated for Belle II applied to the Belle data set, such as the FEI (Full Event Interpretation) hadronic and semileptonic tag. We report new results on differential branching fractions of inclusive $B...
The analysis of B-meson decays to charmed and charmless hadronic final states is a keystone of the Belle II physics program. It allows for theoretically reliable and experimentally precise constraints on the CKM Unitarity Triangle fit, and is sensitive to effects from non-SM physics. Results on branching ratios, direct CP-violating asymmetries, and polarization of various channels, with...
One of the outstanding problems in physics is to explain the baryon-anti-baryon
asymmetry observed in nature. According to the well-known Sakharov criterion for
explaining the observed baryon-anti-baryon asymmetry, it is essential that CP
violation exist in the baryon sector. However, CP violation has only been
observed in mesons decays and is yet to be convincingly demonstrated in...
The tree-level determination of the CKM angle gamma is a standard candle measurement of CP violation in the Standard Model. The latest LHCb results from time-integrated measurements of CP violation using beauty to open charm decays are presented. A new combination of all LHCb measurements is also performed. A precision below four degrees is obtained, which dominates the world average.
BESIII has collected 2.93 fb-1 of data at 3.773 GeV, 6.3 fb-1 of data between 4.18 and 4.23 GeV, and 4.4 fb-1 of data between 4.6 and 4.7 GeV, respectively. The data set collected at 3.773 GeV contains quantum-correlated D0D0bar pairs that allow access to the phase differences between amplitudes. We will report the measurements of strong phase differences in D0(-bar) decays, such as K_S/L pi+...
LHCb has collected the world's largest sample of charmed hadrons. This sample is used to 1) measure direct CP violation in D mesons and charmed baryons 2) measure $D^0-\bar{D}^0$ mixing and the first non-zero mass difference and to 3) search for CP violation in mixing and interference. New measurements from several decay modes are presented, as well as prospects for future sensitivities.
Analyses of D and B meson yields as functions of decay time provide access to fundamental standard model parameters and probe natural non-SM scales at 10-100 TeV energies. Outstanding vertexing performances are key enablers of this program. We prove the capabilities of the Belle II detector by measuring the lifetimes of the D0 and D+ mesons. The results are the most precise to date, owing to a...
BESIII has collected 2.93 fb-1 of data at 3.773 GeV, and 6.3 fb-1 of data between 4.18 and 4.23 GeV, respectively. We will report precison measurements of the decay constants fDs+ and the CKM matrix elements |Vcs| via D(s)+ -> l+v (l=mu, tau), which are important to test the LQCD calculations and the CKM matrix unitarity. We will also present observation of semileptonic decays of D0(+) ->...
The LHCb experiment is playing a crucial role in the study of rare and forbidden decays of charm hadrons, which are sensitive to effects beyond the Standard Model in the up-quark sector. New searches for FCNC-mediated processes and asymmetry measurements in final states with two leptons are presented.
