Tuske O, Chauvin N, Delferriere O, Fils J, Gauthier Y
Commissariat à l'Energie Atomique et aux Energies Alternatives, IRFU, F-91191 Gif-sur-Yvette, France.
GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstr. 1, 64291 Darmstadt, Germany.
Rev Sci Instrum. 2018 May;89(5):052303. doi: 10.1063/1.5017783.
The CEA at Saclay is in charge of developing and building the ion source and the low energy line of the proton linac of the FAIR (Facility for Antiproton and Ion Research) accelerator complex located at GSI (Darmstadt) in Germany. The FAIR facility will deliver stable and rare isotope beams covering a huge range of intensities and beam energies for experiments in the fields of atomic physics, plasma physics, nuclear physics, hadron physics, nuclear matter physics, material physics, and biophysics. A significant part of the experimental program at FAIR is dedicated to antiproton physics that requires an ultimate number 7 × 10 cooled pbar/h. The high-intensity proton beam that is necessary for antiproton production will be delivered by a dedicated 75 mA/70 MeV proton linac. A 2.45 GHz microwave ion source will deliver a 100 mA H beam pulsed at 4 Hz with an energy of 95 keV. A 2 solenoids low energy beam transport line allows the injection of the proton beam into the radio frequency quadrupole (RFQ) within an acceptance of 0.3π mm mrad (norm. rms). An electrostatic chopper system located between the second solenoid and the RFQ is used to cut the beam macro-pulse from the source to inject 36 μs long beam pulses into the RFQ. At present time, a Ladder-RFQ is under construction at the University of Frankfurt. This article reports the first beam measurements obtained since mid of 2016. Proton beams have been extracted from the ECR ion source and analyzed just after the extraction column on a dedicated diagnostic chamber. Emittance measurements as well as extracted current and species proportion analysis have been performed in different configurations of ion source parameters, such as magnetic field profile, radio frequency power, gas injection, and puller electrode voltage.
位于法国萨克雷的法国原子能委员会负责研发和建造离子源以及位于德国达姆施塔特GSI（重离子研究中心）的FAIR（反质子与离子研究设施）加速器综合体的质子直线加速器的低能段。FAIR设施将提供稳定且稀有的同位素束流，涵盖广泛的强度和束流能量范围，用于原子物理、等离子体物理、核物理、强子物理、核物质物理、材料物理和生物物理等领域的实验。FAIR实验计划的很大一部分致力于反质子物理研究，这需要最终达到7×10个冷却反质子/小时的数量。用于产生反质子所需的高强度质子束将由一台专门的75 mA/70 MeV质子直线加速器提供。一台2.45 GHz微波离子源将以4 Hz的频率脉冲输出100 mA的H束流，能量为95 keV。一条由2个螺线管构成的低能束流传输线允许将质子束注入射频四极杆（RFQ），接受度为0.3π mm mrad（标准均方根）。位于第二个螺线管和RFQ之间的静电斩波器系统用于切割来自离子源的束流宏脉冲，以便向RFQ注入36 μs长的束流脉冲。目前，法兰克福大学正在建造一台梯级RFQ。本文报道了自2016年年中以来获得的首次束流测量结果。质子束已从电子回旋共振离子源中引出，并在引出柱之后在一个专门的诊断腔室中进行分析。在离子源参数的不同配置下，如磁场分布、射频功率、气体注入和引出电极电压等，进行了发射度测量以及引出电流和粒子种类比例分析。
