Joint PSP/Taskforce minutes for 27 Feb 2020 ============================ https://beamdocs.fnal.gov/AD-public/DocDB/ShowDocument?docid=8043 (a) No updates from Tan (b) Kiyomi gave an update on flat injection (1) Kiyomi reminds us that the GMPS jitter is ~50 mA which gives a ~1 mm orbit position change. (2) For PIP, orbit excursion is about 2mm without correction. (3) For PIPII orbit excursion is 5 mm without correction. (4) There are two correct: (i) Asymmetric and symmetric compensation. (ii) Both methods can be done in PIP because the maximum slew rate is 3 Tm/s < 3.24 Tm/s limit. (5) In PIPII, the required slew rate for asymmetric compensation is 7.55 Tm/s > 3.24 Tm/s limit. (6) For a 200 kV bucket in PIPII during injection, Kiyomi will need to know dp/p to know how good her correction needs to be. (7) At present, to disentangle whether the flat correction works, DC studies have to because in normal ops, both the RF and the GMPS changes and feedbacks are on. (8) In DC ramp study, experiments with fixed RF voltage, feed back off. (i) Reference orbit taken where the orbit oscillations are minized by tuning VImin and RF frequency. (9) Experiment and calculation showed good agreement when RF and VIMin was changed. (10) Corrections also moved the beam. (i) Simulations with MADX showed general agreement but orbit oscillations larger in measurement. (11) Problem of oscillations traced to HS01 because the corrector is displaced and breaks symmetry of the ring. (12) HS05 used to correct. (i) By using 1dB attenuator on HS05, Kiyomi demonstrated that the horizontal peaks of the oscillations were reduced by about 50%. (ii) The pad has been left in operations. (13) Beam study of the ramp showed that the frequency curve does not seem to match either with the assumed energy or the radius of Booster. (14) Plan for next study period (i) DC studies: use the dipole correctors to correct the B-field changes. (ii) More realistic simulation of real field and frequency. (iii) Real time compensation of 50 mA jitter with cogging card. (iv) GMPS regulation to reduce amplitude of the jitter. (c) Paul observed beam loading with Booster RFSUM (1) RFsum changed between normal $1D, $15 cycles and $13 (SY cycles) (i) This is because SY cycles have 6x lower intensitiies. (2) Paul did calculations to show that the anode curve seems to match the observed RF sum curve. (3) Observed RPOS changed after transition. This is a mystery. (4) Simple simulations show that the longitudinal distribution for low intensity cycles does not match the bucket well. (i) Recyler TARDIS shows the tails in low intensity as well. (5) Some questions arose was to whether the correct shunt impedance was used because the shunt impedance gets larger above transition. (d) Vladimir analyzed the 2019 booster beam study data (1) CHG0 has weird behaviour throughout the ramp. A large unphysical dip is seen between 5 to 10 ms. (2) Vladimir compared toroids and loss monitor at S06 at 10 ms into the cycle. (i) Conclusion is that at low intensities, error of CHG0 is large (~60%). At high intensity there is 100% agreement between CHG0 and IRMS06. (3) Vladimir corrected the the loss at 8 ms and 33 ms. This showed that at low intensity is actually 2.5x better than reported by CHG0. (4) Operational corrections are small ~1 to 1.5% (5) IPM vs MI8 wires were compared. (6) IPM data looks good because they look like gaussians and signal is not saturated. (7) IPM signals are affected by space charge (8) Vladimir found an analytic model to take into account the space charge effect which makes the IPM measure the beam bigger than it is. (9) With correction, the nominal HEP intensity shows nearly 30% growth after injection. There is a drop in emittance that may be from scraping.