Some Proposals for ILC Beam Test Facilities at FNAL

1
Some Proposals for ILC Beam Test Facilities at
FNAL

• Mike Church
• ILC RD Meeting
• 4/19/06

2
Where Did This Come From? -- Agenda and Attendees
for Initial Discussions on Beam Facilities
3/14/06
3
5 Tiered Proposals
4
Beam Test Facilities and What Can Be Learned from
Them
5
Flat Beams from Photoinjector
6
ILCTA _at_ New Muon Lab
round to flat beam transformation
(will be 3)
P. Piot
7
Emittance Evolution in the ILC Main Linac

• Lattice is BCD with 1 Quadrupole per 4 Cryo
  Modules. Length of a FODO cell is 86 m. Number of
  cells is 114
• Initial Beam Energy is 15 GeV, final 250 GeV
• Initial Vertical Normalized Emittance is 20
  nmrad
• The plot shows that large emittance growth occurs
  in the first 10 FODO cells (1 km length), even
  with all steering algorithms applied (both 1-1
  steering and Dispersion Free steering applied).

Projected vertical emittance, using MATLIAR
A. Valishev
8
Emittance Evolution in a Model Test Facility Linac
Projected vertical emittance, using MATLIAR

• Simple model of a Test Linac 10 FODO cells of
  ILC (1 km)
• Initial Beam Energy is 100 MeV, final energy 23
  GeV
• Initial Vertical Normalized Emittance is 20
  nmrad
• With nominal element misalignments and no
  steering applied the emittance growth of 2 orders
  of magnitude is observed

A. Valishev
9
Civil Construction Issues (5 GeV linac)

• A 5 GeV linac should duplicate as much of the ILC
  infrastructure as possible
• 2 tunnel design
• identical RF and cryo distribution systems
• 1 cryoplant/service building
• large access shaft plus emergency egress paths
• vertical curvature

10
Possible Location of 500m Linac Inside Tevatron
Ring
500m linac
C0 collision hall
approximate site of PD
11
A Survey of e- Rings
2 new DR proposals in progress - HERA
competing with XFEL - CESRTF conversion
starting in 2008 1.5 5.5 GeV e and e- low
emittance (3nm) up to .36A(??) competing with
CHESS
12
Cross Section of HERA Magnet in Tevatron Tunnel
13
HERA Tunnel and Magnets
14
Possible Scheme for Positron Production and
Acceleration

• Conventional positron target
• Return beamline to front end of linac
• Two options for acceleration
• Accelerate positron bunches between electron
  bunches spaced at 308 nsec
• Use widely spaced bunches so that interleaved
  positrons/electrons is not an issue
• The point is to fill the positron ring for beam
  stability/emittance studies
• Two options for DR configuration
• Reverse polarity of magnets and circulate
  positrons in same direction as electrons
• Keep polarity the same and have duplicate
  feedback, collimators, masks, aborts, etc

15
This is a Work in Progress with Many Questions
Unanswered

• Could any of these facilities be (or evolve to)
  the final thing?
• Should any of these facilities by deep
  underground? Differences in ground motion,
  temperature/humidity control, etc?
• Can (an upgraded) photoinjector satisfy
  emittance, intensity, and pulse train length
  requirements for linac and DR tests?
• cost? timeline?
• Can competing facilities do better? (CESRTF and
  HERA DR)
• Can any of these facilities have dual use --
  ie, besides ILC beam physics/technology?