Symmetry violation in weak decays

Our current knowledge of particle physics is described by the Standard Model (SM). This model, however, leaves important observations unexplained. To answer these outstanding questions, as of yet, unknown physics is required. In the search for new physics, symmetries and their breaking play a guiding role. This dissertation combines experimental results to find to which extent nature is described by our current theory. For this the breaking of the discrete symmetries: parity, charge-conjugation and time-reversal invariance is studied. In addition the possible breakdown of Lorentz symmetry is considered. The breaking of this fundamental symmetry, that lies at the foundation of both the SM and general relativity, is possible in some of the theoretical models that try to unify the SM and gravity. The breaking of the discrete symmetries in beta decay played a major role in development of the SM. Nowadays, beta-decay experiments also search for new interactions. In this dissertation the significance of beta decay compared to experiments at the Large Hadron Collider and to searches for electric dipole moments is studied. This allowed us to make important recommendations for future beta-decay experiments. There have been many tests of Lorentz invariance, but these left the weak interaction relatively unexplored. In this dissertation, Lorentz-symmetry breaking is studied in a number of weak decays. This allowed us to put limits on the effects of Lorentz-symmetry breaking and to make recommendations for future experiments to further test Lorentz invariance in the weak interaction

Symmetry violation in weak decays

Our current knowledge of particle physics is described by the Standard Model (SM). This model, however, leaves important observations unexplained. To answer these outstanding questions, as of yet, unknown physics is required. In the search for new physics, symmetries and their breaking play a guiding role. This dissertation combines experimental results to find to which extent nature is described by our current theory. For this the breaking of the discrete symmetries: parity, charge-conjugation and time-reversal invariance is studied. In addition the possible breakdown of Lorentz symmetry is considered. The breaking of this fundamental symmetry, that lies at the foundation of both the SM and general relativity, is possible in some of the theoretical models that try to unify the SM and gravity. The breaking of the discrete symmetries in beta decay played a major role in development of the SM. Nowadays, beta-decay experiments also search for new interactions. In this dissertation the significance of beta decay compared to experiments at the Large Hadron Collider and to searches for electric dipole moments is studied. This allowed us to make important recommendations for future beta-decay experiments. There have been many tests of Lorentz invariance, but these left the weak interaction relatively unexplored. In this dissertation, Lorentz-symmetry breaking is studied in a number of weak decays. This allowed us to put limits on the effects of Lorentz-symmetry breaking and to make recommendations for future experiments to further test Lorentz invariance in the weak interaction

Symmetry violation in weak decays

Our current knowledge of particle physics is described by the Standard Model (SM). This model, however, leaves important observations unexplained. To answer these outstanding questions, as of yet, unknown physics is required. In the search for new physics, symmetries and their breaking play a guiding role. This dissertation combines experimental results to find to which extent nature is described by our current theory. For this the breaking of the discrete symmetries: parity, charge-conjugation and time-reversal invariance is studied. In addition the possible breakdown of Lorentz symmetry is considered. The breaking of this fundamental symmetry, that lies at the foundation of both the SM and general relativity, is possible in some of the theoretical models that try to unify the SM and gravity. The breaking of the discrete symmetries in beta decay played a major role in development of the SM. Nowadays, beta-decay experiments also search for new interactions. In this dissertation the significance of beta decay compared to experiments at the Large Hadron Collider and to searches for electric dipole moments is studied. This allowed us to make important recommendations for future beta-decay experiments. There have been many tests of Lorentz invariance, but these left the weak interaction relatively unexplored. In this dissertation, Lorentz-symmetry breaking is studied in a number of weak decays. This allowed us to put limits on the effects of Lorentz-symmetry breaking and to make recommendations for future experiments to further test Lorentz invariance in the weak interaction

Symmetry violation in weak decays

Our current knowledge of particle physics is described by the Standard Model (SM). This model, however, leaves important observations unexplained. To answer these outstanding questions, as of yet, unknown physics is required. In the search for new physics, symmetries and their breaking play a guiding role. This dissertation combines experimental results to find to which extent nature is described by our current theory. For this the breaking of the discrete symmetries: parity, charge-conjugation and time-reversal invariance is studied. In addition the possible breakdown of Lorentz symmetry is considered. The breaking of this fundamental symmetry, that lies at the foundation of both the SM and general relativity, is possible in some of the theoretical models that try to unify the SM and gravity. The breaking of the discrete symmetries in beta decay played a major role in development of the SM. Nowadays, beta-decay experiments also search for new interactions. In this dissertation the significance of beta decay compared to experiments at the Large Hadron Collider and to searches for electric dipole moments is studied. This allowed us to make important recommendations for future beta-decay experiments. There have been many tests of Lorentz invariance, but these left the weak interaction relatively unexplored. In this dissertation, Lorentz-symmetry breaking is studied in a number of weak decays. This allowed us to put limits on the effects of Lorentz-symmetry breaking and to make recommendations for future experiments to further test Lorentz invariance in the weak interaction

QCD factorization of the four-lepton decay B−→ℓνˉℓℓ(′)ℓˉ(′)B^-\rightarrow \ell \bar{\nu}_\ell \ell^{(\prime)} \bar{\ell}^{(\prime)}

Motivated by the first search for the rare charged-current $B$ decay to four leptons, $\ell \bar{\nu}_\ell \ell^{(\prime)} \bar{\ell}^{(\prime)}$, we calculate the decay amplitude with factorization methods. We obtain the $B\to \gamma^*$ form factors, which depend on the invariant masses of the two lepton pairs, at leading power in an expansion in $\Lambda_{\rm QCD}/m_b$ to next-to-leading order in $\alpha_s$, and at $\mathcal{O}(\alpha_s^0)$ at next-to-leading power. Our calculations predict branching fractions of a few times $10^{-8}$ in the $\ell^{(\prime)} \bar{\ell}^{(\prime)}$ mass-squared bin up to $q^2=1~\text{GeV}^2$ with $n_+q>3~$GeV. The branching fraction rapidly drops with increasing $q^2$. An important further motivation for this investigation has been to explore the sensitivity of the decay rate to the inverse moment $\lambda_B$ of the leading-twist $B$ meson light-cone distribution amplitude. We find that in the small-$q^2$ bin, the sensitivity to $\lambda_B$ is almost comparable to $B^- \rightarrow \ell^- \bar{\nu}_\ell\gamma$ when $\lambda_B$ is small, but with an added uncertainty from the light-meson intermediate resonance contribution. The sensitivity degrades with larger $q^2$.Comment: 22 pages, 7 figures; v2: study of the sensitivity to the shape of the B-LCDA added (Sec. 4.4). Matches published versio

Use of multiparametric MRI to characterize uterine fibroid tissue types

Background: Although the biological characteristics of uterine fibroids (UF) have implications for therapy choice and effectiveness, there is limited MRI data about these characteristics. Currently, the Funaki classification and Scale

Rationale and design of the PRAETORIAN-COVID trial:A double-blind, placebo-controlled randomized clinical trial with valsartan for PRevention of Acute rEspiraTORy dIstress syndrome in hospitAlized patieNts with SARS-COV-2 Infection Disease

There is much debate on the use of angiotensin receptor blockers (ARBs) in severe acute respiratory syndrome–coronavirus-2 (SARS-CoV-2)–infected patients. Although it has been suggested that ARBs might lead to a higher susceptibility and severity of SARS-CoV-2 infection, experimental data suggest that ARBs may reduce acute lung injury via blocking angiotensin-II–mediated pulmonary permeability, inflammation, and fibrosis. However, despite these hypotheses, specific studies on ARBs in SARS-CoV-2 patients are lacking. Methods: The PRAETORIAN-COVID trial is a multicenter, double-blind, placebo-controlled 1:1 randomized clinical trial in adult hospitalized SARS-CoV-2–infected patients (n = 651). The primary aim is to investigate the effect of the ARB valsartan compared to placebo on the composite end point of admission to an intensive care unit, mechanical ventilation, or death within 14 days of randomization. The active-treatment arm will receive valsartan in a dosage titrated to blood pressure up to a maximum of 160 mg bid, and the placebo arm will receive matching placebo. Treatment duration will be 14 days, or until the occurrence of the primary end point or until hospital discharge, if either of these occurs within 14 days. The trial is registered at clinicaltrials.gov (NCT04335786, 2020). The PRAETORIAN-COVID trial is a double-blind, placebo-controlled 1:1 randomized trial to assess the effect of valsartan compared to placebo on the occurrence of ICU admission, mechanical ventilation, and death in hospitalized SARS-CoV-2–infected patients. The results of this study might impact the treatment of SARS-CoV-2 patients globally

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a $Z$ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 $< p_{\textrm{T}} < 100$ GeV and in the pseudorapidity range $2.5 < \eta < 4$. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb$^{-1}$. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages