1. PRISM experiment on EMMA Test Non-Scaling optics for PRISM ¼ of the synchrotron oscillation takes ~3 turns in EMMA and ~6 turns in PRISM. Experimental steps (version I): – Inject into EMMA at fixed energy from ALICE with different conditions (transverse amplitudes)with RF on (voltage and phase set to stationary bucket). Extract after ¼ (3/4) of synchrotron oscillation and measure energy and ToF. Analyse the data and reproduce the longitudinal phase space as a function of the transverse amplitude 1 J. Pasternak, R. D’Arcy, bdm

2. PRISM experiment on EMMA Experimental steps (version II): – Inject into EMMA at different equivalent energies with different conditions (transverse amplitudes) with RF on (voltage and phase set to stationary bucket). Extract after ¼ (3/4) of synchrotron oscillation and measure energy and ToF. Analyse the data and reproduce the longitudinal phase space as a function of the transverse amplitude. Can we measure the emittance growth ? Do we need more initial RF phases or energies ? 2

3. PRISM experiment on EMMA Not much progress made in the last run … Only really had ~ 6 hours and remember – Need to extract the beam & measure energy – Everything before extraction has to work … Only have pencil beam – cannot model directly – Take 3 or more bunches to represent PRISM beam – Show rotation that way by changing RF phases Find stable fixed point of RF bucket Vary phase & extract ‘beamlets’ (small bunches) – Lower energy / higher energy 3

4. PRISM experiment on EMMA Have established extraction reliably after n turns – Good transport (though intensity not sufficient to get to Faraday cup at the end of line …) – Beam centred down extraction line However n was small (only 1/2, 3/2, 5/2 turns) – Did not have RF capture of beam which would have been ideal for this experiment Saw beam on YAG01 & YAG03 in extraction – Have script to scale all magnets in extraction line according to energy by Jaroslaw – Make images on YAGs identical 4

5. 5 YAGs used highlighted with red circles PRISM experiment on EMMA

6. Can use ‘overlay’ function with images to do this – Images do look very similar but reduced intensity – Should be able to ‘match’ centroids easily – This should increase accuracy of results … 6 YAG01 – 1/2 turn, no RFYAG03 – 1/2 turn, no RF

7. PRISM experiment on EMMA 7 YAG01 – 3/2 turns, no RFYAG03 – 3/2 (top), 5/2 turns, no RF Can now turn RF on Scale magnets Try to restore beam to the same position

8. PRISM experiment on EMMA 8 YAG01 – 1/2 (top), 3/2 turns, RF onYAG03 – 1/2, RF on All images without correction (no YAG3 for 3/2 turns - acceleration) Behaviour as expected Now use scaling program

9. PRISM experiment on EMMA 9 YAG01 – 3/2 (top), 5/2 turns, RF on, scalingYAG03 – 3/2 (top), 5/2 turns, RF on, scaling

10. PRISM experiment on EMMA Conclusions – Need RF capture of beam to do this well but EMMA was not cooperating on this … – Extraction line difficult to use as beam has been extracted pragmatically so far … – Need precise model for this so as to know initial parameters in better detail – Have good idea what needs to be done (I think) – Feedback to Jaroslaw or myself – Next run hopefully ~ March 2012 – Many things will have changed by the time we come up again – hopefully this does not hinder us but … 10