Difference between revisions of "Beam Test Apr 24 2012"
| Line 1: | Line 1: | ||
= Getting Ready Punchlist = | = Getting Ready Punchlist = | ||
| − | 1) Get matlab ready for emittance measurement. | + | 1) Get matlab ready for emittance measurement. () |
| − | 2) Install control box. | + | (Done) 2) Install control box. |
| − | 3) Clean up imaging system. | + | (Done) 3) Clean up imaging system. |
| − | 4) Determine dipole current setting. | + | (Done) 4) Determine dipole current setting. |
= Emittance Test = | = Emittance Test = | ||
Revision as of 23:26, 20 April 2012
Getting Ready Punchlist
1) Get matlab ready for emittance measurement. ()
(Done) 2) Install control box.
(Done) 3) Clean up imaging system.
(Done) 4) Determine dipole current setting.
Emittance Test
Tune HRRL establish stable beam
1. Looking at the beam position on the screen and by the beam current on FC, try to align beam line. The goal is to center the beam on the screen, and maximize the FC charge as high as possible.
2. Reduced the mis-steering at the quadrupole by tuning steerers in the linac.
3. Optimize steerers, solenoids in linac to get a round electron beam shape and no steering at the quadrupole.
4. One good tune earlier for reference: [Tune HRRL]
10 MeV
Energy is set by bending the beam to dipole at specific current.
Set dipole current for 10 MeV, and bend the beam. Tune the beam energy, until we see peak current at the 45 degree Faraday cup.
Emittance measurement at 10 MeV
This is scan for 10 MeV beam. 40 mAmps peak current. Q1 is on, All other quads are off.
1) Scan from -5 Amps to 5 Amps. Increment at 0.2 Amps.
3) Name images by numbers start from 1. Then go on. Like: -5 Amp is 1, -4.8 Amp is 2, and so on til 5 Amp is named 51.
4) Scan multiple times from -5 to 5 Amps, and put them in different folders. Name folder by number, like 1, 2, 3 etc. After finishing one scan go back to -5 Amps. When going back take small steps (like 1 Amp), do not jump from 5 Amps to -5 Amps directly. After reaching back to -5, wait for few moment (like 10 s).
5) For each time, take back ground images. It should be done when RF is on and gun is off.
6) After the scan take a scope image for the current of the FC after the OTR screen. Lower the current, so the vacuum window do not heat up. This step is to check energy.
15 MeV
Energy is set by bending the beam to dipole at specific current.
Set dipole current for 15 MeV, and bend the beam. Tune the beam energy, until we see peak current at the 45 degree Faraday cup.
Emittance measurement at 15 MeV
3 MeV
Energy is set by bending the beam to dipole at specific current.
Set dipole current for 15 MeV, and bend the beam. Tune the beam energy, until we see peak current at the 45 degree Faraday cup.
Emittance measurement at 3 MeV
7 MeV
Energy is set by bending the beam to dipole at specific current.
Set dipole current for 7 MeV, and bend the beam. Tune the beam energy, until we see peak current at the 45 degree Faraday cup.