41 research outputs found
Status of the RFQ linac installation and conditioning of the Linear IFMIF Prototype Accelerator
Abstract The Radio Frequency Quadrupole (RFQ) linac and 1.6 MW RF power system of the Linear IFMIF Prototype Accelerator (LIPAc) facility in the International Fusion Energy Research Center (IFERC) in Rokkasho (Japan) has been installed and conditioned. During the assembly and tuning process, the RFQ cavity was protected with a temporary tent from the potential deterioration of performance caused by dust. The vacuum in the cavity was improved through the 100 °C baking process of the cavity. The high power test of the 175 MHz RF systems up to 200 kW in CW for each of the eight RF chains was performed for checking its stable output reproducibility in Japan, before connecting 9–3/16 inch coaxial transmission lines from the RF chains to the RF input couplers of the cavity. It was confirmed that the eight RF chains provided the balanced RF power to the single RFQ cavity in-phase using a feedback loop and a synchronization system. The peak power in the cavity achieved 150 kW in the pulsed mode, which corresponds approximately to the required electric field to accelerate proton beam. Such RF conditioning process is ongoing to achieve 600 kW approximately required for deuteron beam commissioning planned in 2018
Design and development of an Allison type emittance scanner for the SPIDER ion source
Low divergence negative ion beams are crucial for the development of ITER-like fusion reactors. SPIDER is the prototype beam source of the ITER heating neutral beam injector, and it recently started beam acceleration, up to a voltage of 30 kV. The main diagnostics used to measure beamlet divergence are a movable diagnostic calorimeter (STRIKE), which gives the thermal footprint of the beamlets; beam emission spectroscopy; and visible imaging. These systems do not allow a direct measurement of single beamlet phase-space distribution, which is useful for comparison with numerical simulations and to estimate accelerator performances. To this purpose, a movable Allison type emittance scanner for the SPIDER negative ion beam was developed and proposed for the installation on the STRIKE supporting structure. This paper describes the numerical analyses performed to dimension the mechanical and electrical components, such as the Faraday cup and the slits. An analytical approach based on the integration of an arbitrary phase-space distribution was adopted in order to simulate the device performances. The constraints due to the operation in a high heat load environment are discussed
Robotic single site versus robotic multiport hysterectomy in early endometrial cancer: a case control study
Upgrade of PIAVE Superconducting RFQs at INFN-Legnaro
Superconducting RFQs (SRFQs), the first SC RFQs ever made operational for users, have been operated on the PIAVE SC heavy ion linac injector at INFN-Legnaro since 2006. The structure is split into two resonators and is limited to the accelerating RFQ sections. The resonators had never exceeded 80% of the design accelerating fields. In 2015, an upgrade plan started, aimed at increasing the accelerating fields, while improving their slow and fast tuning systems, repairing degraded components, imple-menting a LASER alignment method. The upgrade plan was successfully concluded in summer 2017. The resona-tors were kept stably locked for days at a field larger than the nominal one. Eventually, a test beam was accelerated successfully for 72 hours, with negligible locking issues. SRFQs entered once again routine operation in December 2017. The new features will allow to accelerate heavy ions with an A/q value as high as 8.5 (versus a former maximum A/q=7.5), allowing operation of the very first accelerated uranium beams at INFN-LNL, after the relat-ed authorizations shall have been issued.Superconducting RFQs (SRFQs), the first SC RFQs ever made operational for users, have been operated on the PIAVE SC heavy ion linac injector at INFN-Legnaro since 2006. The structure is split into two resonators and is limited to the accelerating RFQ sections. The resonators had never exceeded 80% of the design accelerating fields. In 2015, an upgrade plan started, aimed at increasing the accelerating fields, while improving their slow and fast tuning systems, repairing degraded components, implementing a LASER alignment method. The upgrade plan was successfully concluded in summer 2017. The resonators were kept stably locked for days at a field larger than the nominal one. Eventually, a test beam was accelerated successfully for 72 hours, with negligible locking issues. SRFQs entered once again routine operation in December 2017. The new features will allow to accelerate heavy ions with an A/q value as high as 8.5 (versus a former maximum A/q = 7.5), allowing operation of the very first accelerated uranium beams at INFN-LNL, after the related authorizations shall have been issued
Single-access laparoscopic approach in the surgical treatment of endometrial cancer: A single-institution experience and review of literature
Lymph node staging in grade 1-2 endometrioid ovarian carcinoma apparently confined to the ovary: Is it worth?
Objective: The aim of this study was to assess the disease-free survival (DFS) and overall survival (OS) of patients with grade 1-2 endometrioid ovarian carcinoma apparently confined to the ovary, according to surgical staging. Methods: Multicenter, retrospective, observational cohort study. Patients with endometrioid ovarian carcinoma, surgical procedure performed between May 1985 and December 2019, stage pT1 N0/N1/Nx, grade 1-2 were included. Patients were stratified according to lymphadenectomy (defined as removal of any lymph node versus no lymph node assessment), and subgroup analyses according to tumor grade were performed. Kaplan-Meier curves and cox regression analyses were used to perform survival analyses. Results: 298 patients were included. 199 (66.8 %) patients underwent lymph node assessment. Of these, 166 (83.4 %) had unilateral/bilateral pelvic and para-aortic/caval lymphadenectomy. Eleven (5.5 %) patients of those who underwent lymph node assessment showed pathologic metastatic lymph nodes (FIGO stage IIIA1). Twenty-seven patients (9.1 %) had synchronous endometrioid endometrial cancer. After a median follow up of 45 months (95 %CI:37.5-52.5), 5-year DFS and OS of the entire cohort were 89.8 % and 96.2 %, respectively. Age <= 51 years (HR=0.24, 95 %CI:0.06-0.91; p = 0.036) and performance of lymphadenectomy (HR=0.25, 95 %CI: 0.07-0.82; p = 0.022) represented independent protective factors toward risk of death. Patients undergoing lymphadenectomy had better 5-year DFS and OS compared to those not receiving lymphadenectomy, 92.0 % versus 85.6 % (p = 0.016) and 97.7 % versus 92.8 % (p = 0.013), respectively. This result was confirmed after exclusion of node-positive patients. When stratifying according to tumor grade (node-positive excluded), patients with grade 2 who underwent lymphadenectomy had better 5-year DFS and OS than those without lymphadenectomy (93.0 % versus 83.1 %, p = 0.040 % and 96.5 % versus 90.6 %, p = 0.037, respectively). Conclusion: Staging lymphadenectomy in grade 2 endometrioid ovarian carcinoma patients was associated with improved DFS and OS. Grade 1 and grade 2 might be considered as two different entities, which could benefit from different approach in terms of surgical staging. Prospective studies, including molecular profiles are needed to confirm the survival drivers in this rare setting
Management of endometrial cancer in Italy: a national survey endorsed by the Italian Society of Gynecologic Oncology
Endometrial carcinoma (EC) is a frequent cancer in developed countries, but with evidence for discrepant clinical management. Under the auspices of the Italian Society of Gynecologic Oncology (SIOG), we conducted a survey among Italian centers with ≥20 surgeries for gynecological cancer per year, trying to depict a reliable picture of EC management in our country
Beam Dynamics of the First Beams for IFMIF-EVEDA RFQ Commissioning
International audienceThe installation of the IFMIF-EVEDA RFQ, MEBT, LEBT, source and beam dump was completed in September 2017. The beam dynamics of the first beams for the IFMIF-EVEDA RFQ commissioning is presented. Moreover, a proposal for the CW RFQ steady state commissioning is shown, with a focus on the beam dynamics challenges of the beam transport after the RFQ
Beam Dynamics Simulation and Measurements for the IFMIF/EVEDA Project
International audienceIn the framework of IFMIF/EVEDA project the source and RFQ are ready to be tested with beam. In this article the beam dynamics simulation and the measurement performed in preparation of the first beam injection are presented. The installed line is composed by the proton and deuteron Source with the LEBT composed of two solenoids that inject in the 10 meters long RFQ, the MEBT, diagnostic plate and the beam dump. The line is prepared to be tested with protons of 8 mA in pulsed mode (up to 0.1%)