GSI Vacuum group

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GSI Vacuum group

• GSI Vacuum group
• 5 physicists (Bellachioma, Kollmus, Krämer,
  Reich-Sprenger, Wilfert)
• 7 engineers (Bender, Bevcic, Kaminski, Kurdal,
  Schäfer, Welzel, Wolff)
• 23 technicans (Emmerich, de Cavaco, Gaj,
  Gustafson, Hammann, Herge, Heyl, Horn, Jagsch,
  Kischnik, Kolligs, Kredel, Leiser, Lück, Mühle,
  Müller, Norcia, Quador, Savino, Sigmund, Stagno,
  Thurau, Volz)

• Collaborations
• Mahner, Strubin (CERN) desorption RD
• Assmann (TU München) desorption RD
• Hedlund, Westerberg (TSL) FAIR SIS-upgrade
• Benvenuti, Calatroni, Chiggiato (CERN) NEG
  coating
• Anashin, Krasnov (BINP) FAIR SIS-upgrade
• Reid, Malyshev (CCLRC) FAIR SIS-upgrade
• Yang, Zhang (IMP) FAIR CR UHV

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GSI Vacuum group experience

• Facilities
• UHV Lab (upgrade in 2004/2005)
• NEG coating facility (since 2005)
• Ultrasonic cleaning facility
• Operation experience
• all GSI accelerator Vacuum systems (UNILAC,
  SIS18, ESR, HEBT)
• Upgrade experience
• SIS18, ESR, Vacuum Controls, bakeout
• Installation experience
• all modifications to GSI accelerators and
  experiments
• Project experience
• HICAT UHV layout, Vacuum system procurement,
  complete preassembling and installation of the
  HICAT accelerator facility (2001-2007, volume
  3.5 M),
• CNAO LINAC preassambling and installation
• HITRAP UHV Layout, Vacuum system procurement,
  preassambling and installation

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EU construction Task SIS18-2
Task No Descriptive Title Leading Participant Short description and specific objectives of the task
Management-CNI Management of the CNI GSI Management of the Construction Consortium, controlling, reports, auditing

SIS18-1 GSI
SIS18-2 UHV vacuum upgrade GSI Up-grade of the vacuum system with new magnet chambers, an improved bake-out system, and NEG to reach a static base pressure of 210-12 mbar and to keep the dynamic pressure below 110-11 mbar during operation with the highest intensities of heavy ion beams needed for the IAF.
SIS18-3
SIS18-4
SIS18-5
SIS18-6

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UHV system requirementsfor FAIR (base TR)
Due to ion beam lifetime requirements (e.g. U28
in SIS18) SIS18 bakeable p510-12 mbar ?
SIS18 upgrade ESR bakeable p510-12
mbar SIS100 cold arcs T7-20K bakeable
straight sections T300K p510-12 mbar SIS300
cold arcs T4.2K bakeable straight sections
T300K p510-12 mbar NESR p510-12 mbar
(bakeable) HESR p10-10 mbar (bakeable) RESR
p10-10 mbar (bakeable) CR p10-9 mbar (no
bakeout, HICAT design) HEBT/SFRS length 2.5 km,
70 cold, no bakeout (except differential
pumping sections to rings) all pressures N2
equivalent
SIS100/300
from SIS18
HESR
CR RESR
NESR
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Desorption Phenomena(SIS18 upgrade, SIS100,
SIS300)

• Optimized static pressure
• SIS18 upgrade ? NEG coating of conductance
  limiting vacuum chambers (improved dipole, new
  quadrupole) ? EU construction SIS18-2,
• SIS100, SIS300 use of cryogenic pumping
  (T(magnet camber)lt 7 K)
• 2. Optimized dynamic conditions
• RD program on the underlying physical processes
  ? collimator concept with increased local pumping
  speed ? EU construction SIS18-3

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GSI NEG-coating facility

• Magnetron sputter technique
• CERN patent, technology transfer and license
  agreement between CERN and GSI established in
  2005,
• sample tubes sucessfully coated at GSI,
• large facility for dipole chamber coating almost
  finished (first coating of one SIS18 dipole
  chamber in 11/2005)

• Vacuum Arc NEG deposition
• GSI patent, proove of principle in 2004,
• application for localized coating of components
  and insertions

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Ion Beam Loss induced Desorption (dynamic vacuum)

• Ions lost on the inner surface of vacuum chambers
  release up to 105 molecules (mainly H2, CO ),
• under high ion beam intensity operation with
  medium charged heavy ions desorption could create
  vacuum instabilities and could limit in this way
  maximum ion beam intensities accelerated,
• underlying physical processes were not
  understood,
• 2 experimental setups were put into operation at
  GSI in close collaboration with CERN, TU München,
  TSL ,
• ERDA (Elastic Recoil ion Detection Analysis) and
  the measurement of the desorption process in
  dependence of energy, charge and type of the
  incident ion on different target materials are
  leading to an understanding of the physics,
• the results of the measurements will lead to an
  optimized UHV layout and an effective collimator
  design

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Ion Induced Desorption (1)? direct input to
SIS18 upgrade
Desorption Test Stand

• static vacuum 1x10-10 mbar
• equipped with RGA and extractor
• installed behind SIS18

• availible beam
• protons to uranium
• 15 1000 MeV/u

U73 beam
clear (dE/dx)2 scaling
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Ion Induced Desorption (2)? direct
input to SIS18 upgrade
ERDA Measurements

• Elastic Recoil ion Detection Analysis under UHV
  conditions (1x10-10 mbar)
• target characterization during ion bombarding
• total and partial pressure measurements in
  parallel

oxygen profile
ion beam scrubbing of the oxyde layer -gt linked
to desorption yields (detailed results will be
published EPAC06, H.Kollmus M. Bender)
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SIS18-2 (UHV-upgrade), participating groups
TSL will contribute to SIS18-2, i.e. to the UHV
upgrade program. The role of TSL is to
participate in the upgrade of the SIS18 UHV
dipole chambers. An important part of this
optimization process are measurements to study
desorption rates for layers of NEG coating due to
the impact of light and heavy ions in a broad
energy range from 10 to 1000 MeV/u. They will
contribute 3 professional person-months to
perform the desorption measurements.
CCLRC will also contribute to SIS18-2, i.e. to
the UHV upgrade program. CCLRC is working in the
field of NEG coating for synchrotron radiation
machines. The laboratory will cooperate with GSI
on various topics of simulation calculations. The
contribution in terms of professional
person-months will be of the order of 1
person-month per year.
INP is a leading laboratory in the field of
high-energy electron colliders. INP will take
over a coordinating function for SIS18-2 and take
part in the design, and manufacturing of the new
SIS18 quadrupole chambers. These chambers have to
be designed for a wall thickness below 0.5 mm and
for a bake-out temperature of 3000 C. All
chambers shall be coated (at GSI) with a NEG
layer to achieve the required distributed pumping
speed. For the NEG coating one has to look for
materials, which are proven having lowest
de-sorption yield under heavy ion bombardment.
Participant Roles Personal cost k Investment k total request k
GSI Construction leading Lab 442 291 733
TSL paticipation in desorption measurements at GSI 24 21 45
CCLRC UHV system modelling 25 - 25
BINP design and manufacturing of 15 sets of new 4-pole chamber (long and short type) 51 (177expected) 188 239

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SIS18-2 / timescale
starting has to be shifted to date of signed
contracts
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