arXiv subjects

Mirco Dorigo

Publications and source records attributed to Mirco Dorigo.

8 recordsLinked to original sources

arXiv2025

Unlocking time-dependent $CP$ violation without signal vertexing at $B$ factories

We present a method to measure time-dependent $CP$ violation in $B^0$ decays produced in $Υ(4S) \to B^0\overline{B}^0$ events at $B$ factories without reconstructing the signal decay vertex. The method exploits the sensitivity of the tag $\overline{B}^0$ decay time to $CP$ violation in the $B^0$ signal. It relies on a compact $e^+e^-$ interaction region and excellent vertex resolution, which enable precise measurement of the displacement between production and decay vertices of the tag meson. We study an application to $B^0\toπ^0π^0$ decays using a simplified simulation that approximates the conditions of the Belle II experiment at the SuperKEKB collider. Our approach achieves a sensitivity on mixing-induced $CP$ violation that would require 20 times larger samples with standard approaches. When incorporated into the $B \to ππ$ isospin analysis, the expected results would reduce the degeneracy of $ϕ_2$ solutions and significantly increase precision. This work opens a path to previously inaccessible $CP$-violation studies enhancing and accelerating the reach of Belle II and future flavor physics programs.

hep-ph↗

arXiv2022

Snowmass White Paper: Belle II physics reach and plans for the next decade and beyond

Belle II is an experiment operating at the intensity frontier. Over the next decades, it will record the decay of billions of bottom mesons, charm hadrons, and tau leptons produced in 10 GeV electron-positron collisions at the SuperKEKB high-luminosity collider at KEK. These data, collected in low-background and kinematically known conditions, will allow us to measure hundreds of parameters that test the standard model (SM) and probe for the existence of new particles, at mass scales orders of magnitudes higher than those studied at the energy frontier. We project our sensitivities for measurements that are of primary relevance and where Belle II will be unique or world leading for data corresponding to 1 to 50 ab$^{-1}$. Belle II will uniquely probe non-SM contributions in sensitive $b \to q\bar q s$ decays and charmless $b \to q\bar q d(u)$ decays, semileptonic $b \to s ν\barν$ and $s τ^+ τ^-$ decays, fully leptonic $b \to \ell ν$ decays, and select $c \to u$ processes. Belle II will lead exploration of non-SM physics in $b \to c τν$ and $b \to s γ$ decays and will most precisely determine the quark-mixing parameters $|V_{ub}|$ and $|V_{cb}|$. Belle II will measure many parameters in $τ$ physics to precisions that will be world leading for the foreseeable future, including the electric and magnetic dipole moments, branching fractions for charged-lepton-flavor-violating decays, and quantities that test lepton-flavor universality. Belle II will perform unique searches for dark-sector particles with masses in the MeV-GeV range. We will also pursue a broad spectroscopy program for conventional and multiquark $c \bar c$ and $b \bar b$ states and provide essential inputs to sharpen the interpretation of muon magnetic-anomaly results. Our exploration of uncharted regions of non-SM parameter space with high precision will reveal non-SM particles or set stringent constraints on their existence, guiding future endeavors.

hep-ex↗

arXiv2019

Summary of WG7 at CKM 2018: "Mixing and $CP$ violation in the $D$ system: $x_D$, $y_D$, $|q/p|_D$, $ϕ_D$, and direct $CP$ violation in $D$ decays"

The "10$^{\rm th}$ International Workshop on the CKM Unitary Triangle" took place at the University of Heidelberg on September 17$^{\rm th}$-21$^{\rm st}$, 2018. In this write-up, we summarize the material discussed at the workshop by the Working Group 7, which focused on latest experimental results and theoretical developments in the study of mixing and $CP$ violation in the neutral $D$ system, and of $CP$ violation and decay properties of other charm mesons and baryons.

hep-ex↗

arXiv2013

CP Violation in Hadronic B Decays at CDF

I report recent measurements in b-hadron decays reconstructed in the full data set of \sqrt{s} = 1.96 TeV proton-antiproton collisions collected by the CDF experiment at the Tevatron. These include the final CDF results on: measurements of CP asymmetries in two-body charmless decays of the Bd, Bs, and Λ^0_b hadrons; bounds on the Bs mixing phase and on the decay width difference of Bs mass eigenstates; and updated measurements of branching ratios of Bs->Jpsi Phi and Bs->Ds(*)Ds(*) decays. All measurements are among the most precise from a single experiment and in agreement with the standard model predictions.

hep-ex↗

arXiv2012

Recent heavy flavor results from the Tevatron

The CDF and D0 experiments at the Tevatron ppbar collider have pioneered and established the role of flavor physics in hadron collisions. A broad program is now at its full maturity. We report on three new results sensitive to physics beyond the standard model, obtained using the whole CDF dataset: a measurement of the difference of CP asymmetries in $K^+K^-$ and $π^+π^-$ decays of $D^0$ mesons, new bounds on the $B^0_s$ mixing phase and on the decay width difference of $B^0_s$ mass-eigenstates, and an update of the summer 2011 search for $B^0_(s)$ mesons decaying into pairs of muons. Finally, the D0 confirmation of the observation of a new hadron, the $χ_b(3P)$ state, is briefly mentioned.

hep-ex↗

arXiv2011

Suppressed Bs decays at CDF

We review three recent results of the CDF collaboration on Bs suppressed decays: the first search for CP--violation in the Bs-->phi phi decay, where two CP--violating asymmetries expected to be zero in the Standard Model are measured, and the observation and the branching ratio measurements of Bs-->jpsi fnot and Bs-->jpsi K(*) decays.

hep-ex↗

arXiv2010

Charmless and Penguin Decays at CDF

Penguin transitions play a key role in the search of New Physics hints in the heavy flavor sector. During the last decade CDF has been exploring this opportunity with a rich study of two--body charmless decays of neutral B mesons into charged final--state particles. After briefly introducing the aspects of this physics peculiar to the hadron collision environment, I report on two interesting results: the first polarization measurement of the B^0_s --> phi phi decay and the update of the B^0(_s) --> h^+h'^- decays analysis.

hep-ex↗

arXiv2010

Measurements of the masses, lifetimes and decay modes of hadrons at Tevatron

The Tevatron provides 1.96 TeV ppbar collisions and allows for collection of rich b-hadron samples to the two experiments CDF and D0. The study of heavy flavor properties represents a fruitful opportunity to investigate the flavor sector of the Standard Model (SM) and to look for hints of New Physics (NP). Here we report the first measurement of polarization amplitudes in B^0_s charmless decays, world leading results on b-hadron lifetimes, and measurements of several other properties of b-hadrons.

hep-ex↗