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The High Energy Storage Ring (HESR) is part of the future Facility for Antiproton and Ion Research (FAIR) placed in Darmstadt (Germany). The HESR is designed for antiprotons with a momentum range from 1.5 GeV/c to 15 GeV/c, but will as well be suitable to provide heavy ion beams with a momentum range from approximately 0.6 GeV/c to 5.8 GeV/c. To guarantee smooth operation it is crucial to verify and to optimize the design with beam-dynamics simulations. Within recent studies* calculations based on a variant of the Lyapunov exponent were carried out to estimate the dynamic aperture. The studies could reproduce expected influences as reduced aperture due to tune resonances and tune shifts due to coupling. Thus they can be extended to investigate the dynamic behaviour of the beam and identify the main restrictions to the dynamic aperture near the chosen betatron tune. Furthermore ongoing measurements of the magnetic fields of the already produced bending dipoles and quadrupoles deliver a more precise insight to the harmonic content of these elements. Thus the existing simulations could now be updated by including the new measurement results., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The High-Energy Storage Ring (HESR) is one part of the international Facility for Antiproton and Ion Research (FAIR) at GSI Darmstadt. Forschungszentrum Jülich (IKP and ZEA-1) is responsible for the design and development of the HESR. The HESR is designed for antiprotons and heavy ion experiments as well. Therefore the vacuum is required to be 10⁻¹¹ mbar or better. To achieve this also in the curved sections, where 44 bent dipole magnets are installed, NEG coated dipole chambers will be used to reach the needed pumping speed and capacity. For activation of the NEG a bake-out system is needed. Two test benches were installed to investigate the required equipment needed to reach this low pressure: A vacuum test bench to investigate the influence of different types and quantity of vacuum pumps for the straight sections of the HESR A bake-out test bench for checking the achievable end pressure and develop the bake-out system for the NEG coated dipole chambers in the curved sections of the HESR The results of the tests and the bake-out concept including the layout of the control system and the special design of the heater jackets inside the dipoles and quadrupoles are presented., Proceedings of the 8th Int. Particle Accelerator Conf., IPAC2017, Copenhagen, Denmark

The 2 MeV electron cooler was installed in the COSY ring in the spring 2013. The new system enables electron cooling in the whole energy range of COSY. The electron beam is guided by longitudinal magnetic field all the way from the electron gun to the collector. This well-proven optics scheme was chosen because of the wide electron energy range of 0.025-2 MeV. The electrostatic accelerator consists of 33 individual sections of identical design. Electrical power to each section is provided by a cascade transformer. Electron beam commissioning and first studies using proton and deuteron beams were carried out. Electron cooling of proton beam up to 1662 MeV kinetic energy was demonstrated. Maximum electron beam energy achieved so far amounted to 1.25 MeV. Voltage up to 1.4 MV was demonstrated. The cooler was operated with electron current up to 0.5 A. The paper provides insights into the recent progress in high energy electron cooling at COSY and perspectives for the HESR ring at FAIR., Proceedings of the 5th Int. Particle Accelerator Conf., IPAC2014, Dresden, Germany

COSY Jülich is a cooler synchrotron and storage ring with a proton momentum range from 270 to 3300 MeV/c. It has been conceived to deliver high precision beams for medium energy physics. To accomplish this goal two cooling systems are used. An electron-cooling system that reaches up to a momentum of 645 MeV/c and a stochastic cooling system that covers the upper momentum range from 1500 to 3300 MeV/c. Since its inauguration in April 1993 substantial progress in developing beams for the experiments has been achieved and the physics program has started with first measurements. Proton beams in a wide energy range have been delivered to internal as well as external experiments. Important design features of the machine and results of the commissioning process are presented.

The High Energy Storage Ring (HESR) is part of the upcoming Facility for Antiproton and Ion Research (FAIR) placed in Darmstadt (Germany). The HESR is designed for antiprotons with a momentum range from 1.5 GeV/c to 15 GeV/c, but will as well be suitable to provide heavy ion beams with a momentum range from approximately 0.6 GeV/c to 5.8 GeV/c. To guarantee smooth operation it is crucial to verify and improve the design with beam-dynamics simulations. Particularly the dynamic aperture is calculated as a measure of quality. Complementary to previous beam dynamics calculations based on frequency map analysis*, the dynamic aperture is calculated using a variant of the Lyapunov exponent. The first bending and focusing magnets have been delivered and the magnetic fields measured recently. So the modeled assumptions regarding the multipole imperfections of these elements are now replaced by values based on measurements. This contribution contains the inclusion of the measured values as well as the the tracking-based dynamic aperture calculations., Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea

The High Energy Storage Ring (HESR) is part of the upcoming Facility for Antiproton and Ion Research (FAIR) in Darmstadt (Germany). The HESR is designed for antiprotons with a momentum range from 1.5 GeV/c to 15 GeV/c, but will as well be suitable to provide heavy ion beams with a momentum range from approximately 0.6 GeV/c to 5.8 GeV/c. To guarantee smooth operation it is crucial to verify and improve the design with beam-dynamics simulations. Particularly the dynamic aperture is calculated as a measure of quality. Complementary to previous beam dynamics calculations based on frequency map analysis [1], the dynamic aperture is calculated using a variant of the Lyapunov exponent. The first bending and focusing magnets have been delivered and the magnetic fields measured recently. So the assumed values of the the multipole imperfections used so far in the machine model are now replaced by values based on fieldmeasurements.