Minutes of A0 photoinjector group meeting Monday July 2nd, 2004 http://home.fnal.gov/~piot/FridayMeeting/Minutes/ * Next meeting: Monday July 12th, 2004 * Plan for next week: *** we will run beam everyday both morning and afternoon *** - Tuesday: - tune the laser, commission and startup the data archieving system - measure the laser time-profile using the streak camera (if Rodion here: also try to use the SHG autocorrelator) - Wednesday/Thursday/Friday: - beams studies: try to take data on x-y coupling (hopefully find a cure) and then do some beam studies [Yin-e/Philippe] Discussions: * Achievements of last week: We ran beam only Tuesday [Philippe/Yin-e] and Wednesday [Yin-e]: Monday and Friday was north cave run and Thursday shift was cancelled. -Monday the chicane [Wade/Mike] was removed out of the beamline, to see whether it could explain the observed coupling. Tuesday beam was ran through, and it was found that the x-y coupling is still present. Some spot size data were taken and some test to continue trying to determine the source of coupling was performed. We do not have any clear conclusion and further work is needed next week. -Wednesday quadrupole scans were performed using Q1AX03 and X6, for a magnetized beam, at first sight the beam emittances in the lab. frame (thus including magnetic term) are slightly different for the two transverse planes (emittance value of ~ mm-mrad were measured); but this difference is dependent on the number points taken in the fit (so this might be due to some artifact in the way we do our fit) * Other discussed items: Jamie presented the design that has been devised for the SONY digital mount. The camera will be mounted vertically and view the beam via a 45 deg. mirror. It will cost about 3000 $ of workshop time to make the mount (for 8 cameras). Daniel confirmed that Happek will be here the week of July 19, we need to find out exactly what Uwe wants to do, one of his plan is to bring over an cooled bolometer (if so we need to find out whether we need to have few cable pulled etc...). Since Daniel will be away the next two week Philippe will contact Uwe end of next week and check what he really wants to do and what he need (so that we can plan ahead). * Tasks concerning hardware ACTION ITEM updated: Fri Jul 2 16:50:50 CDT 2004 H8/ calibration of upstream directional coupler and insulator (Markus need to speak to Tim and with Kai to schedule this STATUS?) H13/ Pulse stacker, what do we do? (Rodion) H14/ air coil steerers, Kai will gather all the paper he has and we will decide whether we can give this project to one of the NIU engineering student (Kai, STATUS: nobody at NIU picked up this project...) H21/ the laser uniformity problem can this be due to the new (since late summer) tight focusing in the doubling crystal area to improve conversion efficiency? On going work [Rodion] H26/ trigger problem on a couple of CCD camera (->Kai will look into it 03/2004) H28/ Problem with emittance measurement at X7 (Philippe 04/16/04) H29/ Need daily monitoring of the laser parameters (Jamie/Rodion 04/23/04) [EVERYTHING NOW READY SYSTEM NEED TO BE COMMISSIONED THIS COMING TUESDAY] H32/ Digital camera from SONY(?) need to be ordered (Jason) [ORDERED, ORDER STILL AT FNAL PROCUREMENT] H33/ laser fluctuation since June 1st week [FIXED?] from Adrian Melissinos: NEEDED LASER STUDIES: 1. Study of oscillator bandwidth versus length of compressed pulse. Measure IT length using stepping autocorrelator 2. beam profile (wavefront) studies both in IR and UV in laser room and on virtual cathode. Use spatial filters 3. study of doubling and quadrupling efficencies with old and new crystal, take a tuning curve POSSIBLE LASER UPGRADE PROJECTS 1. Measure IR pulse length before compression (use diode?) implement cw autocorrelation 2. Install new beamline between multipass and 2-pass -- install spatial filter, rebalance 2-pass amplifiers 3. Relay imaging UV from laser room to cave 4. _harware_: replacing all coolers with new system IV + use existing system III as back-up 5. pulse stacker studies, new pulse stacker R&D