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Design and construction of
Nuclotron-based Ion Collider
fAcility (NICA)
and Mixed Phase Detector (MPD)
Conceptual design
proposal by AC WG-II
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NICA general layout by WG-II
NOTE: THE IDEA TO CONSIDER ION
COLLIDER BASED ON THE
NUCLOTRON WAS PUT FORWARD
BY THE ACCELERATOR WORKING
GROUP II
•The possibility of fixed target experiments is exist;
• The investigation of light and middle weight ion collisions including
polarized deuterons (collision energy and luminosity will be larger in the case);
•The experiments at the internal target installed inside one the collider rings
can be considered as well;
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NICA: cost &schedule by WG-II
•Cost of the booster is based on the Nuclotron project cost
scaled as ratio of the lengths.
•The collider rings cost is estimated based on the LHC cost.
The two main scale factors were used: ratio of the lengths (k1)
and ratio of the magnetic fields ( kB 2), i.e. CNICA = CLHC / k1·kB 2 .
Cost of R&D, preparatory work, transfer lines, injection and
extraction systems, radiation safety conditions unexpected
works will increase this cost by a factor of 2-2.5.
• The design and construction of magnets and cryogenic systems of the both as booster and collider
can be made by JINR and JINR member-countries. Part of special works on RF system, fast kickers,
special SC – magnets and some other systems should be performed by those collaborating
Laboratories who have more experience in the mentioned directions.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
The essential cost saving factors
• No new buildings, no additional power supply lines, heat, water cooling;
•The U-beam peak energy (2.5 GeV/u) used in the colliding mode is much less
than that was discussed preliminary for fixed target experiments (5-10 GeV/u);
thus, the problems of radiation safety will take less cost;
•The needed upgrade of the Nuclotron ring including ion source has been
considered and presented within the project “Nuclotron-M”;
•The design of a fast-cycling superferric 84 m booster for the Nuclotron was
made earlier, although the lattice should be redesigned based on the new
specification and the recent data obtained at BNL, CERN and GSI;
• The JINR has a long-term experience in superconducting cables and magnets
design and fabrication, thus magnet-cryostat systems of both as booster and
collider rings can be manufactured by the Institute’s workshops;
• Additional high capacity cryogenic plant is not necessary.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
The existing Nuclotron facility
•The Nuclotron was built for five years (1987-1992), the main
equipment of its magnetic system, and many other systems
as well, was fabricated by the JINR central and the LHE
workshops without having recourse to specialized industry.
The Nuclotron ring of 251.5 m in perimeter is installed in the
tunnel with a cross-section of 2.5m x 3 m that was a part of
the Synchrophasotron infrastructure
The main design criteria specified for
the Nuclotron construction were the
following:
•·
Much less electric power consumption;
•·
Substantial improvements of vacuum
inside a beam pipe;
•·
Faster ramp and longer flat top of the
magnetic field;
•·
Cost saving for materials and work;
•·
Maximum use of the existing facilities
and infrastructure of the Synchrophasotron.
All the mentioned conditions were realized in 1987-93 within the project:
“Replacement of the Synchrophasotron magnetic system by a
superconducting one – Nuclotron”.
NOTE: the injector (ion sources, linac upgrade, booster) and slow extraction
system as were not included in the project due to lack of money
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NUCLOTRON: MAIN PARAMETERS
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
SYNCHROPHASOTRON/NUCLOTRON: ANNUAL RUNNIG TIME
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
SEARCHING for the MIXED PHASE
ACCELERATOR R&D GOAL DISCUSSED
AT THE ROUND TABLE-I:
Au, … , U – ion beams
at the energies above 5 GeV/u
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•
•
•
•
A.D. Kovalenko
THE MAIN NECESSARY
NUCLOTRON DEVELOPMENT
ION SOURCE KRION
VACUUM IN THE RING
FIELD RAMP B  2 T/s
LINAC LU-20 UPGRADE
BEAM DIAGNOSTICS etc.
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
Reaching 5 Gev/u for heavy ions ( A~ 200)
pc(GeV/c•u) = 0.3•B•ρ•(z/A) (Tm), where ρ = L(B)•N/2π
The number of dipoles in the Nuclotron ring, N =96:
•L(@2T) = 1.396 m, ρ =29.917 m and pc = 12.55(z/A)
•L(@2.2T) = 1.385 m,ρ =21.17 m and pc = 13.96(z/A)
A.D. Kovalenko
Operation of the Nuclotron
magnetic system at 2.2 T
make it possible to reach
6.527 GeV/u if z/A=0.5.
Thus, 5 GeV/u can be
reached for z/A =0.383.
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
PROJECT “NUCLOTRON-M”
The project include:
• improvement of the beam pipe pumping system;
• structural magnets power supply upgrade;
• beam extraction system;
• beam diagnostic and control system;
• RF system;
•beam transfer line from the Nuclotron ring to the main
experimental area;
• radiation shield ( F3 area mainly);
• cryogenic supply system;
• ion source development;
• booster magnets R&D
The project “Nuclotron-M” has been prepared for the
approval procedure. The project cost is about 3.0 M USD for
two years starting from 2007.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
Ion source KRION
•The improved EBIS-type ion source KRION is chosen for
generation of the primary beam of highly charged state ions.
•We consider as practically feasible for realization within the coming two
years the new ion source with 6 T solenoid and pulse repetition rate of 5-10
Hz, i.e. (4-8)1010 U30+ ions per second.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NUCLOTRON:
HEAVY ION INJECTION SCHEME
LIMITATION by KRION:
higher charge state– lower intensity
LIMITATION from LU-20: Z/A > 0.3
LIMITATION by the NUCLOTRON:
single-turn injection ( 8.3 mks )
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
Booster/Nuclotron/Collider
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
Booster/Nuclotron/Collider
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
FAST CYCLING BOOSTER
The maximum operating current was increased to
12 kA. The current ramp rate of 120 kA/s was
obtained at cycled operation at 3 Hz. Limitation
from the power supply voltage ( 40 V)
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
BOOSTER
•The version is similar to that presented earlier at ASC’2000, EPAC2000 and EPAC2002.
The circumference of the booster ring is 1/3 of the Nuclotron.
•The large aperture of both lattice dipole and quadrupole magnets is one of the main design
features.
•the magnet cold mass consisting of a SC-winding, a beam pipe, a reinforcing shell and
correcting windings (if needed), is fabricated as a common rigid unit separated from the iron
yoke.
•The yoke temperature of 80 K.
•The cold mass having a substantially lower weight and surface and the cooled iron yoke are
suspended inside the cryostat,
•The two substantial features should be realized in the new design: 1) pulse repetition rate of
5 Hz and 2) high level of vacuum in a beam pipe.
•The possibility to construct superferric magnet operating at 3-5 Hz have been demonstrated
at our Laboratory. The 80K yoke magnet models have been tested also. The new 12 kA NbTi
composite hollow cable have been manufactured and tested. The new booster lattice of DFtype is under optimization. The maximum energy of the booster should exceed 100 MeV/u to
provide reasonable (practically achievable) vacuum level in the Nuclotron beam pipe.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
•
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NICA: 4 T COLLIDER DIPOLE
THE CONCEPT OF HOLLOW CABLE COOLED WITH TWO-PHASE
HELIUM FLOW IS USED. NEVERTHELESS, THE SC WIRES ARE
DIVIDED INTO THREE ELECTRICALLY INSULATED GROUPS.
A.D. Kovalenko
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.
NICA: OPERATION CYCLE & COOLIG POWER
3 x 7 SC wires of
1.04 mm equivalent
diameter each.
Io = 5 kA,
Ic = 7.89 kA
A.D. Kovalenko
The total equivalent refrigerator load
needed to cool the NICA facility will be
3290 W at 4.5 K. Taking into account also
about 30 % capacity reserve, necessary
equivalent capacity of the refrigerators
estimated to 4.3 kW at 4.5 K.
ROUND TABLE DISCUSSION-2, JINR, Dubna, October 6- 7, 2006.