IPBI 6 April 05 Ken Moffeit
Polarimetry Design Updates
- Dispersion in upstream chicane - 20mrad extraction line
0.75 mrad beam stay clearlocation of Synchrotron Radiation Stripe DetectorComments about ShieldingNumber of Cells for Cerenkov DetectorBetter R22 etc
- 2mrad extraction line R22 issuesEnergy and Polarimeter Chicanes
- aligning the Compton IPComments about surveying and tolerance for direction at Compton IPs.
IPBI Meeting6 April 05
Ken Moffeit
IPBI 6 April 05 Ken Moffeit
Upstream Polarimeter with Dispersion = 5 mm
BPC1s = 711.595 m
BPC2730.695 m K Moffeit 31 Apr 05
UpstreamPolarimeter Chicane
10 cm
10 meters
CerenkovDetector
Compton IP250 GeVx = 5 mm
3 cm
Plan View
Angle = 0.24272 mrad
BPC3738.095 m
BPC4760.195 m
250 GeVAngle = 0.24272 mrad
25 GeVAngle = 2.4272 mrad
35 GeVAngle = 1.73371 mrad
4.5 cm
IPBI 6 April 05 Ken Moffeit
Dispersion 5mm > 20mm2 is 16 times larger
R(20mm) = R(5mm)/4R3 (20mm)= R3 (5mm)/32Emittance(20mm) = 45 Emit (5mm)
Slide from Ray Arnold
Upstream Polarimeter Emittance Growth versus Dispersion
IPBI 6 April 05 Ken Moffeit
Emittance Growth versus Dispersion
Hor
izon
tal E
mitt
ance
Gro
wth
Chicane Dispersion (mm)
Mark Woodley
0
10%
20%
30%
0 10 20
For eta=20mm & 500 GeV beam: Short bend has pole-tip field of 5.4 kG;
Long bend is half of that.
Magnets ok for higher dispersion.
IPBI 6 April 05 Ken Moffeit
Upstream Polarimeter with dispersion = 10 mm
BPC1s = 711.595 m
BPC2730.695 m K Moffeit 4 Apr 05
UpstreamPolarimeter Chicane
10 cm
10 meters
CerenkovDetector
Compton IP250 GeV
x = 10 mm
6.14 cm
Plan View
Angle = 0.48544 mrad
BPC3738.095 m
BPC4738.095 m
250 GeVAngle = 0.48544 mrad
25 GeVAngle = 4.8544 mrad
35 GeVAngle = 3.46742 mrad
7.9 cm
3.5 cm
IPBI 6 April 05 Ken Moffeit
Space for Laser Beam Insertion/exit
Only 1.4 meters between the inner dipoles is unacceptable. Peter Schuler needs a nominal 8 meters of space (or 14 meter between magnet centers) for the laser beam insertion/exit.This is to accomodate a crossing angle of 10 mrad, and keep the optics away from any synchrotron radiation. These conditions accomodate a vertical beam crossing, but retain a minimal magnet gap height of only 20 mm for all dipoles.
IPBI 6 April 05 Ken Moffeit
10 mm dispersion and 8m for laser input
BPC1s = 711.595 m
BPC2730.695 m K Moffeit 4 Apr 05
UpstreamPolarimeter Chicane
10 cm
10 meters
CerenkovDetector
Compton IP250 GeV
x = 10 mm
6.14 cm
Plan View
Angle = 0.48544 mrad
BPC3~745 m
BPC4~767 m
250 GeVAngle = 0.48544 mrad
25 GeVAngle = 4.8544 mrad
35 GeVAngle = 3.46742 mrad
7.9 cm
3.5 cm
8meters
IPBI 6 April 05 Ken Moffeit
20 mrad Extraction Line
Eight Cerenkov Cells 1 cm wide Six cover the region between 36 GeV (12 cm from beam line) 25.1 GeV (17.8 cm)And 2 outside the kinematic limit
Location of Synchrotron Detector
Cerenkov Detector Shielding issues:Cells closest to beam pipe will see Synchrotron Radiation (below 10 MeV?)
250 GeV
25 GeV
45.59 GeV
K Moffeit 4 Apr 05
2 mradenergystripe
2 mradenergystripeBVX1
z=59.69 m
3 mradenergystripe
3 mradenergystripe
Shielding
Energy Chicane
Polarimeter Chicane
10 cm
10 meters
SynchrotronStripe Detector
SynchrotronStripe Detector
CerenkovDetector
Wiggler
Low Field
25.1 GeV
BVX2z=61.99 m
BLEXz=64.29 m
BLEXz=66.89 m
WEX1z=65.59 m
0.75mrad
BVX3z=68.19 m
BVX4z=70.49 m
BVX5z=72.79 m
BVX6z=75.09 m
BLEXz=77.39 m
BLEXz=79.99 m
WEX1z=78.69 m
BVX7z=81.29 m
BPM BPM
BVX8z=83.59 m
BVX9z=100.59 m
BVY1z=120.59 m
BVY2z=132.59 m
BVY3z=152.59 m
Compton IP
17.8cm
QFX4z=156.59 m
0.75mrad
35.7 GeV 12.0cm
Synchrotron StripeDetector z=143.69 m
IPBI 6 April 05 Ken Moffeit
LCWS Mar 05 Yuri Nosochkov
Original Optics Improved R22 Optics
bad
Good
IPBI 6 April 05 Ken Moffeit
Yuri Nosochkov (5 April 05)
Most Recent Optics LCWS Improved R22 Optics
GoodNot Good > Lose 1cm at Cerenkov Det1st Cell starts at 13 cm instead of 12 cm2 mrad synchrotrotron swipe barely gets out of 0.75 mrad beam stay clear
IPBI 6 April 05 Ken Moffeit
2mrad extraction line R22 issues Energy and Polarimeter Chicanes
K Moffeit 12 Mar 05
Polarimeter ChicanePlan View
10 m
10 cm
BHEX3Az=180.06 mx=106.20 cm
BHEX3Bz=182.36 mx=107.57 cm
BHEX3Cz=184.66 mx=108.56 cm
BHEX4Bz=198.96 mx=111.81 cm
BHEX4Az=196.67 mx=111.12 cm
BHEX4Cz=201.26 mx=112.88 cm
BHEX4Dz=203.56 mx=114.35 cm
BHEX4Ez=205.86 mx=116.22 cm
Compton IPAngle 8.850 mrad
Angle 7.138 mrad
Angle 5.425 mrad
Angle 3.712 mradAngle 2.0 mrad
Angle 3.621 mrad
Angle 5.242 mrad
Angle 6.863 mrad
Angle 2.0 mradat IR
Focusz=191.66 mx=110.12 cm
25 GeV
CerenkovDetector
Optics ImprovementR22 ~ 1.3 nowNeed R22 ~ 0.5
Expand 2 mrad section to include Energy chicane Polarimeter chicane
IPBI 6 April 05 Ken Moffeit
Aligning the Compton IP
Precision surveying should be good to <50 micro radians
Can precision gyroscopes be used to achieve better accuracy?Perhaps <25 micro radians