Rare decays mediated by <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>b</a:mi><a:mo stretchy="false">→</a:mo><a:mi>s</a:mi><a:mi>ν</a:mi><a:mover accent="true"><a:mi>ν</a:mi><a:mo stretchy="false">¯</a:mo></a:mover></a:math> transitions have been reported the Belle II experiment. The branching ratio of decay <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:msup><f:mi>B</f:mi><f:mo>+</f:mo></f:msup><f:mo...

Abstract We perform a model-independent analysis of $$|\Delta b|=|\Delta d|=1$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mo>|</mml:mo> <mml:mi>Δ</mml:mi> <mml:mi>b</mml:mi> <mml:mo>=</mml:mo> <mml:mi>d</mml:mi> <mml:mn>1</mml:mn> </mml:mrow> </mml:math> processes to test the standard model and probe flavor patterns new physics. Constraints on Wilson coefficients are obtained from global fits $$B^+ \rightarrow \pi ^+ \,\mu ^+\mu ^-$$ <mml:msup>...

We present a systematic global analysis of dineutrino modes $b \to q \,\nu \bar \nu$, $q=d,s$, and charged dilepton \,\ell^+ \ell^-$ transitions. derive improved or even entirely new limits on branching ratios including decays $B^0 (K^0 , X_s)\, \nu $B_s \phi \nu$ (\pi^0, \rho^0)\, from which presently are best constrained: $B^+ (K^+,\pi^+, \rho^+) K^{*0} \nu$. Using SMEFT we obtain flavor constraints the modes, stronger than corresponding ones rare $b$-decay Drell-Yan data, for $e \tau$...

Abstract $$SU(2)_L$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>S</mml:mi> <mml:mi>U</mml:mi> <mml:msub> <mml:mo>(</mml:mo> <mml:mn>2</mml:mn> <mml:mo>)</mml:mo> </mml:mrow> <mml:mi>L</mml:mi> </mml:msub> </mml:math> -invariance links charged dilepton and dineutrino couplings. Phenomenological implications are worked out for flavor changing neutral currents involving strange, charm, beauty top quark transitions in a model-independent way. We put forward...

In 1988 the NA31 experiment presented first evidence of direct CP violation in decay amplitudes. A clear signal with a statistical significance was later established full data samples from NA31, E731, NA48 and KTeV experiments, confirming that is associated quark transition, as predicted by Standard Model. However, theoretical prediction for measured ratio has been subject strong controversy along years. Although underlying physics already clarified 2001, recent release improved lattice...

We analyze patterns from $CP$--violating new physics (NP) in hadronic and semileptonic rare charm $|\mathrm{\ensuremath{\Delta}}c|=|\mathrm{\ensuremath{\Delta}}u|=1$ transitions. Observation of direct $CP$ violation decays, as $\mathrm{\ensuremath{\Delta}}{A}_{CP}$, provides opportunities for $c\ensuremath{\rightarrow}u{\ensuremath{\ell}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}$, $\ensuremath{\ell}=e,\ensuremath{\mu}$ transitions, vice versa. For the concrete case flavorful, anomalyfree...

Rare $|\mathrm{\ensuremath{\Delta}}c|=|\mathrm{\ensuremath{\Delta}}u|=1$ transitions into dineutrinos are strongly Glashow-Iliopoulos-Maiani-suppressed and constitute excellent null tests of the standard model. While branching ratios $D\ensuremath{\rightarrow}P\ensuremath{\nu}\overline{\ensuremath{\nu}}$, $D\ensuremath{\rightarrow}{P}^{+}{P}^{\ensuremath{-}}\ensuremath{\nu}\overline{\ensuremath{\nu}}$, $P=\ensuremath{\pi}$, $K$, baryonic...

Rare charm decays offer the unique possibility to explore flavor-changing neutral-currents in up-sector within Standard Model and beyond. Due lack of effective methods reliably describe its low energy dynamics, rare have been considered as less promising for long. However, this does not exclude perform searches New Physics per se, but a different philosophy work is required. Exact or approximate symmetries allow construct clean null-test observables, yielding an excellent road discovery...

A bstract The known isospin-breaking contributions to the K → ππ amplitudes are reanalyzed, taking into account our current understanding of quark masses and relevant non-perturbative inputs. We present a complete numerical reappraisal direct CP-violating ratio ∈ ′ /∈, where these corrections play quite significant role. obtain Standard Model prediction Re (∈ /∈) = (14 ± 5) · 10 − 4 , which is in very good agreement with measured ratio. uncertainty, has been estimated conservatively,...

The recent measurement of the CP-asymmetry in decay $D \to K^+ K^-$ by LHCb, combined with $\Delta A_{\text{CP}}$, evidences a sizable \pi^+ \pi^-$ decays, which requires dynamical enhancement standard model higher-order contributions over tree-level ones factor two. data furthermore imply huge U-spin breaking, about 4-5 times larger than nominal one $\lesssim 30 \%$ charm. Enhanced breakdown two approximate symmetries points to models that violate and CP disfavors flavor singlet such as...

New bounds on the electric dipole moment (EDM) of charm and bottom quarks are derived using stringent limits their chromo-EDMs. The new limits, $|d_c|<1.5\times10^{-21}\:e\,\text{cm}$ $|d_b|< 1.2\times 10^{-20}\:e\,\text{cm}$, improve previous ones by about three orders magnitude. These indirect have implications for different models physics, including two-Higgs-doublet, leptoquarks, supersymmetry models.

A bstract It has been recently claimed that the axion coupling to fermions is responsible for an oscillating electric dipole moment (EDM) in background of dark matter. In this work, we re-examine derivation effect. Contrary previous studies, point out physical relevance boundary term, which crucial restoring shift symmetry and drastically affects EDM phenomenology. To describe latter, introduce notion a time-averaged effective EDM, encodes term whose magnitude depends on oscillation regime....

A bstract We perform a global analysis of |∆ c | = u 1 transitions using recent data on D 0 → μ + − , π Λ p and decays, work out constraints new physics Wilson coefficients $$ {C}_{7,9,10}^{\left(\prime \right)} <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msubsup> <mml:mi>C</mml:mi> <mml:mrow> <mml:mn>7</mml:mn> <mml:mo>,</mml:mo> <mml:mn>9</mml:mn> <mml:mn>10</mml:mn> </mml:mrow> <mml:mfenced> <mml:mo>′</mml:mo> </mml:mfenced> </mml:msubsup> </mml:math> . While results...

Rare decays mediated by $b \to s \nu \bar \nu$ transitions have been reported the Belle II experiment. The branching ratio of decay $B^+ K^+ is found to be enhanced with respect standard model value. If taken at face value, implications are profound: either lepton flavor universality violated (multi)-TeV-scale, or light new physics involved. This holds in general if $\mathcal{B}(B^+ \nu)$ exceeds $1.2 \cdot 10^{-5} \, (1.3 10^{-5})$ $1 \sigma$ ($2 \sigma$), which tightens a decreasing upper...

Abstract We briefly overview the historical controversy around Standard Model predictions of ε ′ / and clarify underlying physics. A full update this important observable is presented, with all known short- long-distance contributions, including isospin-breaking corrections. The current prediction, Re( ) = (14 ± 5) · 10 −4 [1, 2], in excellent agreement experimentally measured value.

$SU(2)_L$-invariance links charged dilepton and dineutrino couplings. Phenomenological implications are worked out for flavor changing neutral currents involving strange, charm, beauty top quark transitions in a model-independent way. We put forward novel tests of lepton universality conservation $|\Delta c|= |\Delta u|=1$ b|= q|=1$, $q=d,s$, suitable the experiments Belle II BES III. Single production plus dileptons uniquely probes semileptonic four-fermion t|= q'|=1$, $q'=u,c$, couplings...

A recent lattice evaluation of $\varepsilon'/\varepsilon$, finding a 2.1 $σ$ deviation from the experimental value, has revived old debate about possible $\varepsilon'/\varepsilon$ anomaly. The unfounded claims too low Standard Model prediction are based on incorrect estimates that neglect long-distance re-scattering final pions in $K\rightarrow 2π$. In view current situation, we have recently updated calculation, including all known short- and contributions. Our result,...

We present the contributions to electric dipole moments (EDMs) induced by Yukawa couplings of an additional electroweak doublet colour-octet scalars. The full set one-loop diagrams and enhanced higher-order effects from Barr-Zee are computed for quark (chromo-)EDM, along with two-loop Weinberg operator. Using stringent experimental upper limits on neutron EDM, constraints parameter space this model derived.

We perform a model-independent analysis of $|Δb|=|Δd|=1$ processes to test the standard model and probe flavor patterns new physics. Constraints on Wilson coefficients are obtained from global fits $B^+ \to π^+ \,μ^+μ^-$, $B^0_s\to \bar{K}^{*0}\, μ^+μ^-$, $B^0\toμ^+μ^-$, radiative $B X_d \,γ$ decays data. The consistent with but leave sizable room for Besides higher-statistics measurements more data in theory-friendly bins dilepton mass, further complementary observables such as angular...

The recent release of improved lattice data has revived again the interest on precise theoretical calculations direct CP-violation ratio $\varepsilon'/\varepsilon$. We present a complete update Standard Model prediction [1,2], including new re-analysis isospin-breaking corrections which are vital importance in determination this observable. prediction, $\mathrm{Re} (\epsilon'/\epsilon) = (14\pm 5)\cdot 10^{-4}$, turns out to be good agreement with experimental measurement.

It has been recently claimed that the axion coupling to fermions is responsible for an oscillating electric dipole moment (EDM) in background of dark matter. In this work, we re-examine derivation effect. Contrary previous studies, point out physical relevance boundary term, which crucial restoring shift symmetry and drastically affects EDM phenomenology. To describe latter, introduce notion a time-averaged effective EDM, encodes term whose magnitude depends on oscillation regime. For slow...

The recent LHCb determination of the direct CP asymmetries in decays $D^0 \to K^+ K^-, \pi^+ \pi^-$ hints at a sizeable breaking two approximate symmetries SM: and U-spin. We aim explaining data with BSM physics use framework flavorful $Z^\prime$ models. Interestingly, experimental theoretical constraints very much narrow down shape viable models: Viable, anomaly-free models are electron- muon-phobic feature light 10-20 GeV coupling only to right-handed fermions. can be searched for low mass...

Within the Standard Model Effective Field Theory framework, we set indirect constraints on top quark operators that violate baryon number by one unit above TeV scale. We find these are typically many orders of magnitude more stringent than recently derived direct bounds from collider experiments. Therefore, observation violation in top-quark observables at scale would imply a large fine-tuning among across different energy scales. This possibility is not protected under universal radiative...