E-203 Beam studies - Shift Three
Goal: Longitudinal bunch profile measurements with different bunch length.
We want to take data with different bunch length and if possible compare them with TCAV and THz
measurements.
Building on success of the previous run we will repeat the procedure developed for shift 2.
First we will gradually approach our grating from the beam checking the intensity of the background
recorded on LION-20 and PMT:3360 to stop the approach before intercepting the beam.
Beam Configuration: Transverse beam size at SP Chamber (<<0.1mm), Rep rate from 1 to 10Hz.
Minimal dispersion. Bunch length must be measured with TCAV during shift. Charge and bunch length jitter
needs to be low during the measurement (we take 100 shots and average them – would like max of 1%
jitter on charge and bunch length if achievable for the 100 shots).
Time estimate: 4 hours
Procedure Details:
1.
2.
3.
Contact MCC and ask them to measure transverse sizes using wire scans (WS3 and 4) also ask for
TCAV measurements if available.
Take data for optimum position of each grating at 10Hz. THz performing measurements
parasitically (if they would like to). While moving the gratings we will monitor PMT3360 to avoid
beam interception.
Ask MCC to change the bunch length and repeat item (2). Contact MCC and ask to measure
transverse sizes using wire scans (WS3 and 4) and TCAV. Ideally we would like to measure 3
different bunch lengths over shift duration.
Operations: Maintain steady orbit and assist in wire scan measurements and TCAV
measurements.
For all grating the following procedure should always be followed
1. Moving the grating slowly monitoring signal on PMT 3360 and LION20 to avoid interception.
2. Check that gratings are in such a position that all detectors record a spectrum that is well above
background level.
3. Repeat for all gratings.