1. APEX Report: March 31 – April 1, 2009 Fulvia Pilat Time Meeting, April 7, 2009

2. APEX Schedule March 31 - April 1 2009 3:30am00:30am8pm10:30pm 08-27 Optics, beta* measurements Bai Store rot93 12x12 ramp BBQ OPERATIONS IR nonlinear corrections Pilat 6am Store rot93 6x6 ramp 09-05 D0-DX study MacKay Test of beta*=0.5m ramp Bruno Tepikian 8am No beam pp93lowbeta AGS OFF Injection Driven Triplet Oscillations measurement Minty Thieberger 09-22 Spin tune vs. orbit Ptitsyn, Bai Injection

3. Driven triplet oscillations Thieberger, Minty, +team Summary: Measurement log of driven triplet oscillation measurements in the blue ring for offline analysis given in table above. Triplet quadrupole Q2 in sector 6 was modulated using 2 actuators driven in phase with variable frequency and amplitude. The triplet positions (8 detectors in all), the beam positions at the IP’s, and the betatron tunes were recorded. Complete data sets were acquired for three driving frequencies. -Thieberger, Montag, Fischer, Michnoff, Minty Horizontal beam positionHorizontal tune Example of data for actuator drive frequency of 10.30 Hz with successively decreasing drive amplitude

4. IR corrections (yellow) Pilat, Zimmer Normal sextupole and skew sextupole in the IR6 and IR8 triplets gets readjusted during the set-up phase. Blue got adjusted several week ago, yellow slipped during set- up and ramp-up, and was canceled in the last 2 APEX sessions due to down-time 12x12 rotator ramp, no Artus, IPM, BBQ on the ramp, anticogged (blue used by driven triplet oscillation study) Check/fix orbit, coupling, separate tunes >0.012 Take BBQ tune data as a function of bump amplitude (IR bumps for sextupole correction span both triplets) horizontal bump  normal sextupole vertical bump  skew sextupole 1 normal and 1 skew sextupole per triplet available to correct correctors at  x max affect mostly the H-tune, at  y max mostly the V-tune, not quite orthogonal knobs but close Nice operational instructions by Chris Zimmer: http://www.cadops.bnl.gov/AGS/Operations/docum/NLOCorrection.html Instructions are also in OpsWiki under the name 'IRBump‘ Binello, Zimmer working on automation of correction for 100 GeV PP run

5. IR8 normal sextupole

6. IR6: normal sextupole

7. Effect of IR correction on tune ripple ( from Michiko)

8. Spin tune study Ptitsyn, Bai APEX: ramp 2 APEX: ramp 1 operation 300 murad angle -> 0.046 spin tune shift at 250 GeV Orbit angle in snakes

9. Snake angle in present operation At 9 o’clock the zero orbit angle at snake location leads to few mm excursion at a neighboring location. In both rings.

10. Indication of Blue spin tune at injection is further away from 1/2 with no change of snake orbital angle -0.3mrad snake angle at injection in Blue seems to push the spin tune either close or further away from 1/2 +-0.3mrad snake orbital angle change along the ramp: Yellow shows difference in polarization transmission Difference in Blue is not so clear. Spin tune close to ½ (?). Conclusions

11. APEX Schedule April 8, 2009 4pm 109 bunches 2pm7am9:30am Pp93 109 bunches Regular intensity 07-19, 07-20 Noise from Main PS Schultheiss Minty 6pm 09-05 D0-DX study MacKay Satogata 08-17 Tuning of pp93lowbeta ramp Bruno 7pm11:00am 08-17 Commissioning pp93lowbeta ramp Satogata Tepikian Ptitsyn Marusic, etc. (commissioning team) pp93lowbeta Ramps No beam pp93lowbeta Ramps w/beam BBQ FEEDBACK Back to physics pp93 12x12 ramp BBQ Injection 08-29, 08-10 Polarimeter: rate dependence Huang, Zelenski Pol team CONTINGENT: OPERATIONS High intensity study Bai