Status and progress on the Nuclotron-M project in 2008.
Development and creation of a heavy-ion source based on the KRION technology (subproject SP1.1)
It was performed 4 runs (one month each) on the existing ion source KRION-2 (solenoid field 3T) with the following results:
-Developed, manufactured and experimentally tested new electron gun with increased cathode diameter (1.2mm); automatic system for regulation of the emitter current during one electron pulse; diagnostic system for the string dynamics formation and ion trapping;newscheme of the cell for ion (the following gases: CН4, N2, O2и Ar) pulsed injection into the electron string for ion-ion cooling; new electron beam external modulator at 8 keV (it is required to have pulsed electrons injected at the energy not less than 7 keVfor getting Xe44+ ions);
-It was provided series of experiments aimed to get highly-charged Xe ions at the continuous Xe-gas injection into electron string. Ions of Xe36+ at electron energy Einj=3.7kV were obtained. It was found out that continuous injection of Xe gas follows to the instabilities and cathode poisoning. So it was realized that pulsed injection of the Xe for the experiments is required and it is planned to use new tested cell (above mentioned), but unfortunately it will be impossible to use ion cooling.
-It is planned to perform 4 experimental runs at the existing KRION-2 in the 1st half of 2009 in order to prepare KRION-2 for operation in the Nuclotron run (autumn 2009) with ions Xe44+ (A=129, Z/A=0,341).
Concerning the development of the new ion source KRION-6T there were obtained the following results in 2008:
-All calculations and modeling works for the magnetic system and electron optics were successfully performed; prototypes of the electron gun and electron reflector for KRION-6T were designed, constructed and successfully tested at KRION-2; prototype of the external modulator aimed to operate at 16-18 kV was constructed and successfully tested at 9 kV.
-Designed and manufactured elements of the electron drift tube and ion trap for the structure at 4,2K
-Designed and manufactured all main elements of the automatic spooling machine tool for manufacture of superconducting solenoid coil, special software for the spooling process was created.
-Designed, manufactured and tested all elements of the vacuum vessel for KRION-6T source (the most important and difficult – complex vacuum flanges). Vacuum system of the source is assembled and ready for the vacuum tests. Developed and constructed non-oil vacuum pumping system for the KRION-6T, all necessary elements are purchased and manufactured.
a)b)
Figure1. a) assembled vacuum system and cryogenic vessel of the new source KRION-6T; b) new automatic machine tool for solenoid coil spooling.
Improvement of the power supplies, shielding and energy evacuation systems of the lattice magnets and lenses (subproject SP1.2)
-Successfully designed, developed and tested prototype of the power supply for current increment in the F-lenses;
-Works on the old power lines dismounting and routing of the new power supply cable lines (several kilometers ov kV cables) in total were started in October’08 and are in active phase now. Special space in the basement of synchrophazotron in under preparation and rebuilding – here is planned to be a central transformer point with 6 systems of energy evacuation keys (EEK), managed remotely. EKK are in good progress – all sets are assembled and all power electronics had been successfully tested. Blocks with control electronics are under construction and testing – the goal is to have ready and assembled EEK by middle of 2009.
-Power supply and control systems for injection part (inflector plates) were totally reconstructed and there were manufactured 2 modern kits of such system in order to have one for operation, another - for reserve in case of emergency;
-The console with 4 new power supplies and its new energy evacuation system for the beam bump was manufactured, tested and installed in the ring;
-Main Nuclotron power supplies (19TV and 20 TV) were totally re-constructed, re-mounted and had been prepared for the machine operation at 1,5T (experimentally tested at equivalent current 4500A). Before that only one power supply could operate at 1,5-2T. All this activity is performed in the frame of total modernization of power system of the accelerator complex.
-Special prototype of energy evacuation system (modernized existing electronic scheme with new thyristors) was succesfully constructed and installed in the ring tunnel. It will allow safely to operate with Nuclotron magnetic system at magnetic fields up to 1,5T (corresponds to the kinetic energy 2,6÷4,2 GeV/n depending of the ratio Z/A 0,3÷0,5)
a) b)
c) d)
Figure 2. a) Team of creators with ready 6 sets of the energy evacuation systems (ESS), b) New HV (6kA, 300V) transformer point in the basement of b.1; c) New prototype of the ESS for nearest Nuclotron run (allow to operate at 1.5T); d) New electronics consoles for control of magnetic field at optic elements.
Upgrade of the vacuum system of the Nuclotron ring (subproject SP1.3)
We assume that 1st stage of the Nuclotron vacuum system modernization is completed in the sense of equipment installation. The realization of the 2nd stage has been started and now the main works are concentrated in development of the automatic control system for the Nuclotron vacuum equipment. It has to provide:
-remote switching ON/OFF and control by all vacuum equipment;
-measurement, delivery of information and visualization of the vacuum system parameters;
-equipment protection during emergencies.
These works are performed in close collaboration with Czech companies (Vacuum Praha, FOTON) using modern electronic component. Works were started from design stage in July’08 and have to be completed in February’09 by commissioning of the system, budget of works is about100k$
Some modernization of the vacuum chamber parts had been performed.
The new pick-up station in the cryostat assembly is under completion – the design was started in July, LHEP workshops manufactured all elements and assembled pick-up station. Now we are starting the process of cryogenic measurements and after end of tests that assembly will be installed in February in the ring for operation.
The kit of 8 ionic pumps which were installed at Nuclotron in the end of 1990-s were dismounted and transferred in December’08 to Czech company Vacuum Praha for full modernization. It is planned to refine, fix and equipped them with new power supplies. After that they will be send back to JINR and mounted on the ring for operation. This will allow to improve vacuum level.
a) b)
Figure 3. a) 8 ionic vacuum pumps ready for transportaion to Prague, b) Pick-up station during assembly and tests at LHEP workshops;
Development of the RF system, driving electronics and beam capture system (subproject SP1.4)
The following scope of works was performed since middle of 2008:
-Completed all hardware works on the reconstruction of cable lines for the measurement of beam orbit. Software will be ready by the beginning of the next run in middle of February;
-3 existing pick-up stations (#2, 11 and 16) were totally revised and experimentally tested at room and He temperatures and now are ready for the run at machine;
-special shielding for the 2nd RF station (RFS#4) and plugs of HV cables to this station were manufactured and installed in a tunnel. This allows to decrease noise from RF on the beam signal by factor of 10-15;
-Works on the creation of new control system of RF and B (magnetic field) synchronization with new digital synthesizer and accuracy of 0,01 Gauss are in the final stage and its prototype will be tested in the coming run.
a) b)
Figure 4. a) Modernized RF station #4 in the tunnel, b) power electronics of the RF station;
Extraction of accelerated heavy ions at the maximum energy (subproject SP1.5)
Works on designof new high voltage power supply for the electro-static septum in the LHEP design bureau were completed in autumn 2008, before simulation and modeling works wereperformed. Prototype of such system was constructed and successfully tested up to 160 kV (existing septum power supply doesn’t allow to increase voltage more than 110 kV – this valuegives an opportunity to extract beam effectively only up to 2,3 GeV/n). Now all the elements of new power supply had been manufactured at LHEP workshops and this system is under assembly. We plan to install it on the cryostat in the slow extraction sector by February 2009 in order to provide experiments on beam extraction at energy 4 GeV/n during coming Nuclotron run.
a) b)
Figure 5. a) 3D technical drawing of the new power supply for electrostatic septum which is under final assembly at LHEP workshops; b) electrostatic septum in the tunnel.
Modernization of the automation system for control, beam diagnostics and monitoring of parameters of the accelerator complex (subproject SP1.6)
The upgrade of the automation and diagnostic systems is in very active phase. We continuously order, purchase and install new modern equipment in the ring tunnel.
New Nuclotron synchronization (timing) control system is under active development now – it was started in July 2009. Existing scheme and circuits are reconstructed with modern electronics and new control software is applied. It is planned to complete this work in the middle of 2009, but main prototypes will be tested in coming run.
The existing Control System for the Main Magnet Power Supplies (MPSC) has been operating successfully since the beginning of the first Nuclotron runs. A new control and monitoring system for the Nuclotron main power supplies was designed recently in collaboration with our Slovakian colleagues in order to substantially extend functionality of the existing equipment and software.Now the new MPSC is under adjustment and testing. Investigation of the system shows that its performance is well within the specification. Operational conveniences of the MPSC allow an operator to rapidly respond to the experimentalist’s requirements for the Nuclotron cycle. Some comparison data of the present and new control systems are presented below.
Performance / Present / NewPulse function generator:
– master oscillator frequency
– number of vectors / 1 MHz
4K / 2.5 MHz
32K
Control sequence generator: minimal sampling step / 10 Gs / 0.5 Gs
Analog function generator:
– resolution
– optical isolation
– self–calibration / 16 bit
No
No / 18 bit
Yes
Yes
B (QD, QF)–timer:drift correction / No / Yes
Pulse train analyzer:number of sampling points / 0.4K / 64K
This MPSC system will is under commissioning now and will be used as regular in Nuclotron runs starting from February 2009.
We started R&D works on new position-sensitive pick-up stations, which planned to be elliptical electrodes shape and will be located in points near orbit correctors. The goal to design and construct such pick-ups is absence of spare place in the ring for usual round-shape pick-ups. Now there are round 20 pick-up stations in the ring, we need to add at least 8 (betatron tune of Nuclotron is around 7). In the coming run we plan to install 1 addition round-shape pick-up, later one more. All other stations will be new elliptical. It is planned to construct and manufacture them at LHEP workshops and commission at least one such pick-up in the run on autumn 2009.
The console with power supply units (4 pieces, Glassman Inc) was successfully assembled and installed in the remote control room in the Nuclotron building – it will work as automated kit of power supplies for correctors of the beam bump system. Before installation they we successfully tested and those experiments help us to define the specification for the serial power supply for beam orbit correction system. In January 2009 we signed a Contract with Slovakian Insitutes and factories on the construction and delivery to LHEP the series of 50 power supplies before middle of 2010 to equip Nuclotron with full-scale automatic beam orbit correction system (the budget is about 175 kE). First power supply will be delivered in Spring 2009, next 24 devices – by autumn run at Nuclotron in 2009.
Working prototype of the absolutely beam orbit measurement system has been created in summer 2008 and successfully tested. Now it is active phase of the serial manufacture of full-scale system (for 28 pick-up stations) is ongoing. The budget expenses on this system is about 70k$. We plan to commission and install on the ring several (about 10) digital station by the coming run start and experimentally test them with circulating beam.
System of control, blocking and access protection was totally reconstructed during last 4 months, all the cables and protection doors were checked.New automatic system controlling the protection signals and locks was tested and commissioned in January 2009 and is ready for operation in the coming run.
a) b)
Figure 6. a) Console with 4 new power supplies for beam bump, b) new MPSC system;
Extracted beam transport channels and their radiation shielding (subproject SP1.7)
Extracted beam profilometers (first half of extraction channel) were re-designed and reconstructed; diagnostic system for the extracted beam intensity measurement was revised and reconstructed;
Large volume of work was performed in the field of control and measurement of the coil current in magnets and lenses of beam transportation channel. Before we had only tools for manual measurement of magnet parameters. By February 2009 the new automatic system (industrial PC, 32-channel block, active filter modules, cable lines, complex software) for measurement and control of coil current will be commissioned and used by operation personnel (accelerator and experimental physicists) during the run. It will help to have detailed information about unstable work of magnetic optic elements.
Improvement of the cryogenic supply system (subproject SP1.8)
The full-scale modernization of the LHEP cryogenic complex was started in June 2008 after run 38.
We had a contract with KRIOGENMASH plant aimed on the total modernization of the oil-cleaner unit for liquid Helium at KGU-1600 plant. This unit (MO-800)is very complicated 13-tonnsystem with cryogenic and high-pressure ingredients. The budget of works is 110k$ and this work was successfully completed during July-November, whole unit was transported to the plant near Moscow and it was totally fixed and reconstructed. The margin of safety for the modernized MO-800 is 12 years. It was successfully delivered back to JINR in December 2008 and installed in KGU-1600 complex, now is under final commission.
The next very large scope of works in collaboration with HELIIMASH Company and is referred to the full scale modernization of other important elements and units of the LHEP He-liquefier complex: large volume of welding and mechanical works, dismounting and reconstruction of 12 grease (oil) separators and absorbers, re-filling those blocks with new adsorbent powder, flushing and refining all those vessels, training and testing of these vessels, refining of all He pipelines with special modern technology using Freon gas. The total budget of these works is about 400k$. They were started in August 2008 and have to be completed by February when all reconstructed equipment (several tons) will be delivered from HELIIMASH plant back to JINR and will be mounted and commissioned during 1-2 weeks. The margin of safety for the renewed equipment of KGU-1600 has to be around 10-15 years.
Such reconstruction procedures of the KGU-1600 will allow the accelerator complex of LHEP to be safe and stable operational for prolonged runs and will decrease liquid He and liquid nitrogen consumption sufficiently.
LHEPcontinues modernization of the control system for cryogenic complex. All components for the console with control and diagnostic devices for automatic control of compressors and liquefiers are purchased and are under test now at the laboratory. The construction and assembly will be started in Spring 2009.
LHEP have a negotiation with HELIIMASH about leasing in the nearest time special auto-tank for liquid helium. Such an object will allow us to be independent on the delays in transportation and to avoid waist of liquid helium during its transference within the LHEP ground for different purposes (runs at Nuclotron, runs at superconducting ion source, some R&D cryogenic works in laboratory facility) and as a result reduction of the operation costs.
a)b)
c)d)
Figure 7. Modernization of the Nuclotron cryogenics.
a) Delivery of the block MO-800 to LHEP JINR, b) Dismounting welding works at KGU-1600, c) dismounting of oil-separator vessels, d) KGU-1600 complex general view with installed MO-800 – blue block in the right corner.
Creation of a new preaccelerator with injection and extraction channels (subproject SP1.9)
Technical design report (detailed version) of new heavy ion linac was prepared by our IHEP (Protvino) colleagues in December 2008. Preparation of first assembly drawings and technical documentation gas been started at the LHEP design bureau.Technical task for building where new linac will be located is under development.
Development and creation of a high-intensity polarized deuteron source (subproject SP1.10)
We continue collaboration works with INR (Troitsk) on the development of the new high-intensity polarized deuteron source, and signed an addendum for work prolongation in 2009. We plan to complete TDR documentation in this year and start construction of some elements at INR.
Simulation, modeling and design of different elements of the future source is in active phase at LHEP.
Experimental hall for the future test bench with that source is prepared at LHEP building 203A, preparation electrical and water-cooling works were performed.
It is planned to purchase part of necessary vacuum equipment (turbomolecular pumps) for the SPD realization in 2009.
Infrastructure works
Modernization of the engineering infrastructure is under active development. Large scope of works in energetic, water cooling/heating systems was successfully performed. Repair-civil works in the buildings of the accelerator complex are undergoing.
We continueseason geodetical measurements in the tunnel of Nuclotron in order to accumulate statistics and analyze soil and basement movement in the accelerator vicinity.
Key moments and expected results on the current stage of the project