422 research outputs found
Measurement of elastic scattering in antiproton-proton collisions at 52.8 GeV centre-of-mass energy
No full textWe measured the differential cross section for p̄p and pp elastic scattering in the momentum-transfer range 0.01 0.09 GeV2, b(p pbar) = 10.68 +- 0.26 GeV ^(-2). Using the optical theorem, we obtained for the total cross section View the MathML source and, by integrating the differential cross section, we obtained for the total elastic cross section σ_tot(p pbar) = 44.86 +- 0.78 mb. Calculations of σ_tot combining elastic-rate and total-rate measurements are also given. All of these measurements were also performed for pp scattering at the same energy, and the results for both reactions are compared
Measurements of elastic scattering in alpha-alpha and alpha-proton collisions at the CERN intersecting storage rings
No full textWe measured the elastic scattering of αα at sqrt(s) = 126 GeV and of αp at sqrt(s) = 89 GeV. For αα, the differential cross section dσ/dt has a diffractive pattern minima at |t| = 0.10 and 0.38 GeV^2. At small |t| = 0.05−0.07 GeV^2, this cross section behaves like exp[(100 ± 10) t]. Extrapolating a fit to the data to the optical point, we obtained for the total cross section α_tot(αα) = 250 ± 50 mb and an integrated elastic cross section σ_e1(αα) = 45 ± mb. Another method of estimating σ_tot(αα), based on measuring the interaction rate, yielded 295 ± 40 mb. For αp, dσ/dt has aminimum at |t| = 0.20 GeV^2, and for 0.05 < |t| < 0.18 GeV^2 behaves like exp[(41 ± 2) t]. Extrapolating this slope to |t| = 0, we found σ_tot(αp) = 130 ± 20 and σ_e1(αp) = 20 ± 4mb. Results on pp elastic scattering at sqrt(s) = 63 GeV agree with previous ISR experiments
A new measurement of the K±→π±γγ decay at the NA48/2 experiment.
No full textThe NA48/2 experiment at CERN collected two data samples with minimum bias trigger conditions in 2003 and 2004. A measurement of the rate and dynamic properties of the rare decay K-+/- -> pi(+/-)gamma gamma from these data sets based on 149 decay candidates with an estimated background of 15.5 +/- 0.7 events is reported. The model-independent branching ratio in the kinematic range z = (m(gamma gamma)/m(K))(2) > 0.2 is measured to be B-MI(z > 0.2) = (0.877 +/- 0.089) x 10(-6), and the branching ratio in the full kinematic range assuming a particular Chiral Perturbation Theory description to be B(K-pi gamma gamma) = (0.910 +/- 0.075) x 10(-6)
Observation of a cusp-like structure in the pi0 pi0 invariant mass distribution from K+ --->pi+- pi0 pi0 decay and determination of the pi pi scattering lengths.
No full textWe report the results from a study of a partial sample of ∼2.3×107 K±→π ±π0π0 decays recorded by the NA48/2 experiment at the CERN SPS, showing an anomaly in the π0π0 invariant mass (M00) distribution in the region around M00=2m+, where m+ is the charged pion mass. This anomaly, never observed in previous experiments, can be interpreted as an effect due mainly to the final state charge exchange scattering process π+π -→π0π0 in K±→ π±π+π- decay [N. Cabibbo, Phys. Rev. Lett. 93 (2004) 121801]. It provides a precise determination of a 0-a2, the difference between the ππ scattering lengths in the isospin I=0 and I=2 states. A best fit to a rescattering model [N. Cabibbo, G. Isidori, JHEP 0503 (2005) 21] corrected for isospin symmetry breaking gives (a0-a2)m+=0.268±0. 010(stat)±0.004(syst), with additional external uncertainties of ±0.013 from branching ratio and theoretical uncertainties. If the correlation between a0 and a2 predicted by chiral symmetry is taken into account, this result becomes (a0-a2)m+=0. 264±0.006(stat)±0.004(syst)±0.013(ext)
Precise measurement of the K+- --->pi+-e+e- decay.
No full textA sample of 7253 K ± → π ± e + e - (γ) decay candidates with 1.0% background contamination has been collected by the NA48/2 experiment at the CERN SPS, which allowed a precise measurement of the decay properties. The branching ratio in the full kinematic range was measured to be BR = (3.11 ± 0.12) × 10 - 7, where the uncertainty includes also the model dependence. The shape of the form factor W (z), where z = (M e e / M K) 2, was parameterized according to several models, and, in particular, the slope δ of the linear form factor W (z) = W 0 (1 + δ z) was determined to be δ = 2.32 ± 0.18. A possible CP violating asymmetry of K + and K - decay widths was investigated, and a conservative upper limit of 2.1 × 10 - 2 at 90% CL was established. © 2009 Elsevier B.V. All rights reserved
Single-cell transcriptomics identifies Mcl-1 as a target for senolytic therapy in cancer
No full textCells subjected to treatment with anti-cancer therapies can evade apoptosis through cellular senescence. Persistent senescent tumor cells remain metabolically active, possess a secretory phenotype, and can promote tumor proliferation and metastatic dissemination. Removal of senescent tumor cells (senolytic therapy) has therefore emerged as a promising therapeutic strategy. Here, using single-cell RNA-sequencing, we find that senescent tumor cells rely on the anti-apoptotic gene Mcl-1 for their survival. Mcl-1 is upregulated in senescent tumor cells, including cells expressing low levels of Bcl-2, an established target for senolytic therapy. While treatment with the Bcl-2 inhibitor Navitoclax results in the reduction of metastases in tumor bearing mice, treatment with the Mcl-1 inhibitor S63845 leads to complete elimination of senescent tumor cells and metastases. These findings provide insights on the mechanism by which senescent tumor cells survive and reveal a vulnerability that can be exploited for cancer therapy
Materials and techniques for percutaneous retrieval of intravascular foreign bodies
No full textThe presence of an intravascular foreign body represents a well-known risk of serious complications. While in the past surgical removal of intravascular foreign body was the most common intervention, nowadays a percutaneous approach in the retrieval of an intravascular foreign body is widely accepted as the first-line technique. In the literature, many case reports describe different techniques and materials. This article summarizes and illustrates the main materials and techniques currently applied for percutaneous retrieval of intravascular foreign body, providing a simplified tool with different interventional possibilities, adaptable to different clinical situations
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