Subthreshold Ξ

Results on the production of the double strange cascade hyperon Ξ^{-} are reported for collisions of p(3.5 GeV)+Nb, studied with the High Acceptance Di-Electron Spectrometer (HADES) at SIS18 at GSI Helmholtzzentrum for Heavy-Ion Research, Darmstadt. For the first time, subthreshold Ξ^{-} production is observed in proton-nucleus interactions. Assuming a Ξ^{-} phase-space distribution similar to that of Λ hyperons, the production probability amounts to P_{Ξ^{-}}=[2.0±0.4(stat)±0.3(norm)±0.6(syst)]×10^{-4} resulting in a Ξ^{-}/(Λ+Σ^{0}) ratio of P_{Ξ^{-}}/P_{Λ+Σ^{0}}=[1.2±0.3(stat)±0.4(syst)]×10^{-2}. Available model predictions are significantly lower than the measured Ξ^{-} yield.

Vaginal self-sampling is a cost-effective way to increase participation in a cervical cancer screening programme: a randomised trial.

BACKGROUND: Cervical cancer screening coverage remains insufficient in most countries. Our objective was to assess whether in-home vaginal self-sampling with a dry swab for high-risk human papillomavirus (HR-HPV) testing is effective and cost-effective in increasing participation in cervical cancer screening. METHODS: In March 2012, 6000 unscreened women aged 30-65 years, living in a French region covered by a screening programme, who had not responded to an initial invitation to have a Pap smear were equally randomised to three groups: 'no intervention'; 'recall', women received a letter to have a Pap smear; and 'self-sampling', women received a self-sampling kit to return to a centralised virology laboratory for PCR-based HPV testing. RESULTS: Participation was higher in the 'self-sampling' than in the 'no intervention' group (22.5% vs 9.9%, P<0.0001; OR 2.64) and 'recall' group (11.7%, P<0.0001; OR 2.20). In the 'self-sampling' group, 320 used the self-sampling kit; for 44 of these women with positive HR-HPV test results, 40 had the recommended triage Pap smear. The ICER per extra screened woman was 77.8[euro ] and 63.2[euro ] for the 'recall' and 'self-sampling' groups, respectively, relative to the 'no intervention' group. CONCLUSIONS: Offering an in-home, return-mail kit for vaginal self-sampling with a dry swab is more effective and cost-effective than a recall letter in increasing participation in cervical cancer screening.

Deep subthreshold Xi;{-} production in Ar + KCl reactions at 1.76A GeV.

We report first results on a deep subthreshold production of the doubly strange hyperon Xi;{-} in a heavy-ion reaction. At a beam energy of 1.76A GeV the reaction Ar + KCl was studied with the High Acceptance Di-Electron Spectrometer at SIS18/GSI. A high-statistics and high-purity Lambda sample was collected, allowing for the investigation of the decay channel Xi;{-} --> Lambdapi;{-}. The deduced Xi;{-}/(Lambda + Sigma;{0}) production ratio of (5.6 +/- 1.2_{-1.7};{+1.8}) x 10;{-3} is significantly larger than available model predictions.

Dielectron production in 12C+12C collisions at 2A GeV with the HADES spectrometer.

The invariant-mass spectrum of e+e- pairs produced in 12C+12C collisions at an incident energy of 2 GeV per nucleon has been measured for the first time. The measured pair production probabilities span over 5 orders of magnitude from the pi(0)-Dalitz to the rho/omega invariant-mass region. Dalitz decays of pi(0) and eta account for all the yield up to 0.15 GeV/c(2), but for only about 50% above this mass. A comparison with model calculations shows that the excess pair yield is likely due to baryon-resonance and vector-meson decays. Transport calculations based on vacuum spectral functions fail, however, to describe the entire mass region.