24 research outputs found
Endoscopic hemostasis in the ulcer gastro-duodenal hemorrhage, using high-frequency biological welding electro-ligature
Objective. To improve the efficacy of endoscopic hemostasis for the ulcer gastro-duodenal hemorrhage, using high-frequency biological welding electro-ligature.
Materials and methods. In 2017-2020 yrs period the analysis of efficacy of endoscopic hemostasis was done in 160 patients, ageing 40-85 yrs old, for the ulcer gastro-duodenal hemorrhage. The patients were distributed into two groups: the main - 80 patients, in whom high-frequency biological welding electro-ligature was performed, and a control one - 80 patients, in whom monopolar thermal argon-plasm coagulation was conducted.
Results. In the main Group a primary hemostasis was achieved in 77 (96.3%) patients. Early recurrence of hemorrhage have occurred in 3 (3.8%) patients. In a control Group a primary hemostasis was achieved in 66 (82.5%) patients. Recurrence of the hemorrhage have occurred in 14 (17.5%) patients.
Conclusion. Endoscopic hemostasis for the ulcer gastro-duodenal hemorrhage, using high-frequency biological welding electro-ligature, is achieved due to the impedance action of modulated signal of a high-frequency current as well as the adaptive system of automatic guidance of the welding process and a contact between special endoscopic probe, owing a concave electrode, with bleeding vessel, leading to its complete obliteration. Application of welding electro-ligature for endoscopic hemostasis in the ulcer gastro-duodenal hemorrhage, using high-frequency biological welding electro-ligature, guarantees more secure residual hemostasis, than application of monopolar thermal argon-plasm coagulation, peculiarly in hemorrhage from vessels owing 2 - 4 mm diameter. As a result, the hemorrhage recurrence rate have had reduced down to 3.8% (in the control Group - 18.0%)
Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment
In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved.Peer Reviewe
The SHiP experiment at the proposed CERN SPS Beam Dump Facility
The Search for Hidden Particles (SHiP) Collaboration has proposed a general-purpose experimental facility operating in beam-dump mode at the CERN SPS accelerator to search for light, feebly interacting particles. In the baseline configuration, the SHiP experiment incorporates two complementary detectors. The upstream detector is designed for recoil signatures of light dark matter (LDM) scattering and for neutrino physics, in particular with tau neutrinos. It consists of a spectrometer magnet housing a layered detector system with high-density LDM/neutrino target plates, emulsion-film technology and electronic high-precision tracking. The total detector target mass amounts to about eight tonnes. The downstream detector system aims at measuring visible decays of feebly interacting particles to both fully reconstructed final states and to partially reconstructed final states with neutrinos, in a nearly background-free environment. The detector consists of a 50 m long decay volume under vacuum followed by a spectrometer and particle identification system with a rectangular acceptance of 5 m in width and 10 m in height. Using the high-intensity beam of 400 GeV protons, the experiment aims at profiting from the 4 x 10(19) protons per year that are currently unexploited at the SPS, over a period of 5-10 years. This allows probing dark photons, dark scalars and pseudo-scalars, and heavy neutral leptons with GeV-scale masses in the direct searches at sensitivities that largely exceed those of existing and projected experiments. The sensitivity to light dark matter through scattering reaches well below the dark matter relic density limits in the range from a few MeV/c(2) up to 100 MeV-scale masses, and it will be possible to study tau neutrino interactions with unprecedented statistics. This paper describes the SHiP experiment baseline setup and the detector systems, together with performance results from prototypes in test beams, as it was prepared for the 2020 Update of the European Strategy for Particle Physics. The expected detector performance from simulation is summarised at the end
Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target
The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to (3.27±0.07) à 1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill
Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment
In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved
Measuring the heavy neutrino oscillations in rare W boson decays at the Large Hadron Collider
Sensitivity of the SHiP experiment to dark photons decaying to a pair of charged particles
BDF/SHiP at the ECN3 high-intensity beam facility
The BDF/SHiP collaboration has proposed a general-purpose intensity-frontier experimental facility operating in beam-dump mode at the CERN SPS accelerator to search for feebly interacting GeV-scale particles and to perform measurements in neutrino physics. CERN is uniquely suited for this programme owing to the proton energy and yield available at the SPS. This puts BDF/SHiP in a unique position worldwide to make a breakthrough in a theoretically and experimentally attractive range of the FIP parameter space that is not accessible to other experiments. The existing ECN3 experimental facility makes it possible to implement BDF at a fraction of the cost of the original proposal, without compromising on the physics scope and the physics reach. SHiP has demonstrated the feasibility to construct a large-scale, versatile discovery experiment capable of coping with protons per year at 400 GeV/c and ensuring a < 1-event background for the FIP decay search even up to PoT. With the feasibility of the facility and the detector proven, the BDF/SHiP collaboration are ready to proceed with the TDR studies and commence implementation in CERNâs Long Shutdown 3. During the operational lifetime of BDF/SHiP, several prominent opportunities for upgrades and extensions are open, such as the use of a LAr TPC, a synergistic tau flavour violation experiment, and exploiting the secondary mixed-field radiation from the proton target for nuclear and astrophysics, as well as for material testing