A
bstract
Rare kaon decays offer a powerful tool for investigating new physics in
s
→
d
transitions. Currently, many of the interesting decay modes are either measured with rather large uncertainties ...compared to their theoretical predictions or have not yet been observed. The future HIKE programme at CERN will provide unprecedented sensitivity to rare kaon decays, allowing for strong constraints on new physics scenarios with lepton flavour universality violation. We present the overall picture that emerges from a study of the different decay modes with a global analysis considering projections based on the HIKE programme, both with and without KOTO-II future measurements. We also highlight the most relevant decays and identify that in addition to the “golden channel”,
K
+
→
π
+
ν
ν
¯
, the rare
K
L
→
π
0
ℓ
ℓ
¯
decay, especially in the electron sector offers strong constraints on short-distance physics.
The rare kaon decay K+→π+ℓ+ℓ− offers insights into Standard Model (SM) physics and beyond. Driven by vector form factor in the SM, it can also probe non-standard contributions. In this letter we ...study the scalar contribution, fS. Using differential decay width and Forward-Backward Asymmetry we propose a simultaneous fit to vector and scalar contributions which is necessary for a consistent analysis. Novel bounds on |fS| are presented for the first time through a reinterpretation of the E865, NA48/2, and NA62 experimental results. The analysis results in the most precise bound fS<7.9×10−6 at 90% confidence level.
This Letter provides a new determination of the ten real coefficients that describe the structure of the K→πππ amplitudes in the limit where isospin is conserved and complex phases, due to either CP ...violation or final-state rescattering, are neglected. This determination is obtained through a fit to the data on the Dalitz-plot structures and partial-decay rates collected during the last twenty years by several high-precision experiments. The fitting procedure and the way the experimental data have been handled in the fit are discussed in detail. Our fit leads to a more precise determination of the coefficients describing the linear and quadratic slopes of the K→πππ amplitudes.
Cardiac resynchronization therapy is not effective in a variable proportion of heart failure patients. An accurate knowledge of each patient’s electroanatomical features could be helpful to determine ...the most appropriate treatment. The goal of this study was to analyze and quantify the sensitivity of left ventricular (LV) activation and the electrocardiogram (ECG) to changes in 39 parameters used to tune realistic anatomical-electrophysiological models of the heart. Electrical activity in the ventricles was simulated using a reaction-diffusion equation. To simulate cellular electrophysiology, the Ten Tusscher-Panfilov 2006 model was used. Intracardiac electrograms and 12-lead ECGs were computed by solving the bidomain equation. Parameters showing the highest sensitivity values were similar in the six patients studied. QRS complex and LV activation times were modulated by the sodium current, the cell surface-to-volume ratio in the LV, and tissue conductivities. The T-wave was modulated by the calcium and rectifier-potassium currents, and the cell surface-to-volume ratio in both ventricles. We conclude that homogeneous changes in ionic currents entail similar effects in all ECG leads, whereas the effects of changes in tissue properties show larger inter-lead variability. The effects of parameter variations are highly consistent between patients and most of the model tuning could be performed with only ~10 parameters.
Indirect searches have the potential to probe scales beyond the realm of direct searches. In this paper, we consider the implications of two parity violating experiments: weak charge of proton QWp ...and the Caesium atom QWCs on the solutions to lepton flavor nonuniversality violations in the decay of B mesons. Working in a generic implementation of a minimal Z′ model, we assume the primary contribution being due to the electron to facilitate comparison with the low q2 parity violating experiments. We demonstrate that the conclusion is characterized by different limiting behavior depending on the chirality of the lepton current. The correlation developed in this study demonstrates the effectiveness in studying the synergy between different experiments leading to a deeper understanding of the interpretation of the existing data. It is shown that a possible future improvement in the parity violating experiments can have far reaching implications in the context of direct searches. We also comment on the prospect of addition of the muon to the fits and the role it plays in ameliorating the constraints on models of Z′. This offers a complimentary understanding of the pattern of the coupling of the new physics to the leptons, strongly suggesting either a muon only or a combination of solutions to the anomalies.
We present a general analysis of extensions of the Standard Model which satisfy the criterion of Minimal Flavour Violation (MFV). We define this general framework by constructing a low-energy ...effective theory containing the Standard Model fields, with one or two Higgs doublets and, as the only source of SU(3)
5 flavour symmetry breaking, the background values of fields transforming under the flavour group as the ordinary Yukawa couplings. We analyse present bounds on the effective scale of dimension-six operators, which range between 1 and 10 TeV, with the most stringent constraints imposed by
B→
X
s
γ. In this class of theories, it is possible to relate predictions for FCNC processes in
B physics to those in
K physics. We compare the sensitivity of various experimental searches in probing the hypothesis of MFV. Within the two-Higgs-doublet scenario, we develop a general procedure to obtain all tan
β-enhanced Higgs-mediated FCNC amplitudes, discussing in particular their impact in
B→ℓ
+ℓ
−,
ΔM
B
and
B→
X
s
γ. As a byproduct, we derive some two-loop tan
β-enhanced supersymmetric contributions to
B→
X
s
γ previously unknown.
We investigate the capabilities of deep learning based on a convolutional neural network (CNN) to improve the solution of an electromagnetic inverse source problem against a classical regularization ...scheme, the truncated singular value decomposition (TSVD). We consider a planar, scalar source and a far-zone observation domain, for which the unknown-to-data relation is provided by a two-dimensional Fourier-like operator. The exploited a priori information is a weak geometrical information for TSVD, whereas for CNN a priori information is the one embedded during the training stage. As long as the objects belong to a subset matching the information used for the training stage, the nonlinear processing of the neural network (NN) outperforms the linear processing of the TSVD by extrapolating out-of-band harmonics. On the other side, the NN performs poorly when the object does not match the a priori information. The results are of general interest for problems where the Fourier inversion is considered.
We assessed the efficacy and safety of total neoadjuvant therapy, including targeted agent plus FOLFOXIRI (5-fluorouracil, leucovorin, oxaliplatin and irinotecan) induction chemotherapy followed by ...intensified chemoradiotherapy (CRT) and surgical resection, in patients with locally advanced rectal cancer.
This was a single-arm, single-centre phase II trial. Eligible patients had non-metastatic locally advanced rectal adenocarcinoma. Based on Ras-BRAF status, patients were treated with bevacizumab (mutated Ras-BRAF) or panitumumab/cetuximab (wild-type Ras-BRAF) plus FOLFOXIRI regimen followed by oxaliplatin–5-fluorouracil-based CRT and surgery. The primary end point was pathological complete response rate. Secondary end points were toxicity, compliance, tumour downstaging, complete resection, surgical complications, local and distant failures and overall survival. The sample size was planned to expect an absolute 20% improvement in pathological complete response rate over historical literature data with an α error of 0.05 and a power of 80%.
Between October 2015 and September 2019, 28 patients (median age 66 years) were enrolled. All patients had regional lymph node involvement at diagnosis. FOLFOXIRI plus bevacizumab was administered in 11 mutated Ras-BRAF patients, whereas the 17 wild-type Ras-BRAF patients received FOLFOXIRI plus panitumumab/cetuximab. Overall, total neoadjuvant therapy was well tolerated and 26 patients (92.9%) completed the programmed strategy. A complete response was achieved in nine cases (32.1%) and a nearly pathological complete response (ypT1 ypN0) in two patients (7.2%). There was no evidence of febrile neutropenia and no grade 4 adverse events were recorded. Radical resection was achieved in all cases.
FOLFOXIRI plus targeted agent-based induction chemotherapy and intensified CRT before surgery showed promising clinical activity and was well tolerated in locally advanced rectal cancer patients. This phase II trial provides a strong rationale for phase III studies.
A
bstract
The kaon sector is characterised by several processes which are under active investigation across different experiments. In this work, we present the global picture that emerges from a ...study of the different decay modes. We begin by revisiting the theoretical component of these decays and providing up-to-date predictions of the Standard Model as well as the corresponding uncertainties. Several new features emerge, in particular for
K
S,L
→
μ
μ
¯
, and are presented in considerable detail. This offers an ideal platform for extracting the parameter space supported by the existing data. Motivated by possible lepton flavour universality violation in
B
decays, we investigate such Beyond the Standard Model effects also in rare kaon decays. Without loss of generality, our primary analyses correspond to the paradigm where the Wilson coefficients for operators involving tau leptons are chosen to be equal to that involving the muon, i.e.
δC
τ
=
δC
μ
. We conclude by presenting the possible picture that can be achieved towards the end of the run of data accumulation in the planned experiments. This includes assumptions on possible sensitivity goals that the experiments can aim to achieve, in order to extract the kind of physics highlighted in this paper.
A
bstract
This report details the capabilities of LHCb and its upgrades towards the study of kaons and hyperons. The analyses performed so far are reviewed, elaborating on the prospects for some key ...decay channels, while proposing some new measurements in LHCb to expand its strangeness research program.
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