Large-angle production of charged pions by 3 GeV/c - 12.9 GeV/c protons on beryllium, aluminium and lead targets

Measurements of the double-differential $\pi^{\pm}$ production cross-section in the range of momentum 100 \MeVc \leq p < 800 \MeVc and angle 0.35 \rad \leq \theta < 2.15 \rad in proton--beryllium, proton--aluminium and proton--lead collisions are presented. The data were taken with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \GeVc to 12.9 \GeVc hitting a target with a thickness of 5% of a nuclear interaction length. The tracking and identification of the produced particles was performed using a small-radius cylindrical time projection chamber (TPC) placed inside a solenoidal magnet. Incident particles were identified by an elaborate system of beam detectors. Results are obtained for the double-differential cross-sections at six incident proton beam momenta (3 \GeVc, 5 \GeVc, 8 \GeVc, 8.9 \GeVc (Be only), 12 \GeVc and 12.9 \GeVc (Al only)) and compared to previously available data

Measurement of the production of charged pions by protons on a tantalum target

A measurement of the double-differential cross-section for the production of charged pions in proton--tantalum collisions emitted at large angles from the incoming beam direction is presented. The data were taken in 2002 with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 \GeVc to 12 \GeVc hitting a tantalum target with a thickness of 5% of a nuclear interaction length. The angular and momentum range covered by the experiment (100 \MeVc \le p < 800 \MeVc and 0.35 \rad \le \theta <2.15 \rad) is of particular importance for the design of a neutrino factory. The produced particles were detected using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. Track recognition, momentum determination and particle identification were all performed based on the measurements made with the TPC. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections ${{\mathrm{d}^2 \sigma}} / {{\mathrm{d}p\mathrm{d}\theta}}$ at four incident proton beam momenta (3 \GeVc, 5 \GeVc, 8 \GeVc and 12 \GeVc). In addition, the pion yields within the acceptance of typical neutrino factory designs are shown as a function of beam momentum. The measurement of these yields within a single experiment eliminates most systematic errors in the comparison between rates at different beam momenta and between positive and negative pion production.Comment: 49 pages, 31 figures. Version accepted for publication on Eur. Phys. J.

Measurement of the production cross-section of positive pions in the collision of 8.9 GeV/c protons on beryllium

The double-differential production cross-section of positive pions, $d^2\sigma^{\pi^{+}}/dpd\Omega$, measured in the HARP experiment is presented. The incident particles are 8.9 GeV/c protons directed onto a beryllium target with a nominal thickness of 5% of a nuclear interaction length. The measured cross-section has a direct impact on the prediction of neutrino fluxes for the MiniBooNE and SciBooNE experiments at Fermilab. After cuts, 13 million protons on target produced about 96,000 reconstructed secondary tracks which were used in this analysis. Cross-section results are presented in the kinematic range 0.75 GeV/c < $p_{\pi}$ < 6.5 GeV/c and 30 mrad < $\theta_{\pi}$ < 210 mrad in the laboratory frame.Comment: 39 pages, 21 figures. Version accepted for publication by Eur. Phys. J.

Single photon induced symmetry breaking of H2 dissociation

H{sub 2}, the smallest and most abundant molecule in the universe, has a perfectly symmetric ground state. What does it take to break this symmetry? Here we show that the inversion symmetry can be broken by absorption of a linearly polarized photon, which itself has inversion symmetry. In particular, the emission of a photoelectron with subsequent dissociation of the remaining H{sub 2}{sup +} fragment shows no symmetry with respect to the ionic H+ and neutral H atomic fragments. This result is the consequence of the entanglement between symmetric and antisymmetric H{sub 2}{sup +} states resulting from autoionization. The mechanisms behind this symmetry breaking are general for all molecules

EULAR definition of difficult-to-treat rheumatoid arthritis

Background: Despite treatment according to the current management recommendations, a significant proportion of patients with rheumatoid arthritis (RA) remain symptomatic. These patients can be considered to have ‘difficult-to-treat RA’. However, uniform terminology and an appropriate definition are lacking. Objective: The Task Force in charge of the „Development of EULAR recommendations for the comprehensive management of difficult-to-treat rheumatoid arthritis” aims to create recommendations for this underserved patient group. Herein, we present the definition of difficult-to treat RA, as the first step. Methods: The Steering Committee drafted a definition with suggested terminology based on an international survey among rheumatologists. This was discussed and amended by the Task Force, including rheumatologists, nurses, health professionals and patients, at a face-to-face meeting until sufficient agreement was reached (assessed through voting). Results: The following three criteria were agreed by all Task Force members as mandatory elements of the definition of difficult-to-treat RA: 1) Treatment according to EULAR rec-ommendation and failure of ≥2 b/tsDMARDs (with different mechanisms of action) after failing csDMARD therapy (unless contraindicated); 2) presence of at least one of the follow-ing: at least moderate disease activity; signs and/or symptoms suggestive of active disease; inability to taper glucocorticoid treatment; rapid radiographic progression; RA symptoms that are causing a reduction in quality of life; 3) the management of signs and/or symptoms is perceived as problematic by the rheumatologist and/or the patient. Conclusions: The proposed EULAR definition for difficult-to-treat RA can be used in clinical practice, clinical trials and can form a basis for future research

EULAR points to consider for the management of difficult-to-treat rheumatoid arthritis

Objective: To develop evidence-based European Alliance of Associations for Rheumatology (EULAR) points to consider (PtCs) for the management of difficult-to-treat rheumatoid arthritis (D2T RA). Methods: A EULAR Task Force was established comprising 34 individuals: 26 rheumatologists, patient partners and rheumatology experienced health professionals. Two systematic literature reviews addressed clinical questions around diagnostic challenges, and pharmacological and non-pharmacological therapeutic strategies in D2T RA. PtCs were formulated based on the identified evidence and expert opinion. Strength of recommendations (SoR, scale A-D: A typically consistent level 1 studies, D level 5 evidence or inconsistent studies) and level of agreement (LoA, scale 0-10: 0 completely disagree, 10 completely agree) of the PtCs were determined by the Task Force members. Results: Two overarching principles and eleven PtCs were defined concerning diagnostic confirmation of RA, evaluation of inflammatory disease activity, pharmacological and nonpharmacological interventions, treatment adherence, functional disability, pain, fatigue, goal setting and self-efficacy and the impact of comorbidities. The SoR varied from level C to D. The mean LoA with the overarching principles and PtCs was generally high (8.4-9.6). Conclusions: These points to consider for D2T RA can serve as a clinical roadmap to support healthcare professionals and patients to deliver holistic management and more personalised pharmacological and non-pharmacological therapeutic strategies. High-quality evidence was scarce. A research agenda was created to guide future research

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR