# Presentation: 321310

##  Accelerator Performance (10/14-10/20)

- Accelerator Studies (4 shifts)
* **Tevatron (required ramp maintenance and emittance improvement)*
*Testing New A1 optics to lower pbar emittance*
*Ramp orbit,tune,chromaticity maintenance*
*Parse low beta squeeze*
*Vertical damper commissioning*
*Dedicated 140 mA stack to Recycler*

- All Experimenters Meeting

- 21 October 2002

## Tevatron ramp and squeeze

- Tuesday Studies
- Smoothed orbit up the ramp and thru the squeeze
- Adjusted tunes and chromaticities on the ramp and squeeze
- After the A11 quenches
- Orbits are fine
- Apertures at A0 are fine
- Lowered horizontal tune at injection and flattop
- Lowered chromaticity on ramp and flattop
- Found flipped tunes... re-adjusted

- All Experimenters Meeting

- 21 October 2002

## Tevatron tunes

- Initial Ramp tunes

- Final Ramp tunes

- Final Squeeze tunes

- All Experimenters Meeting

- 21 October 2002

## Vertical Damper

-   Found/fixed hardware problems
-   Verified vertical damper stabilizes beam
-     at zero chromaticity

-   Demonstration of signal suppression by
-     tickling the beam with dampers on & off

-   Impact on proton lifetime depends on
-   tunes
-   chromaticity & damper

- Helix on

- Qv

- C4 losses

- Damper

- All Experimenters Meeting

- 21 October 2002

## Pbars to the Recycler

- Stacking pbars in the Recycler

- Cold beam

- Hot Beam

- Injection

- All Experimenters Meeting

- 21 October 2002

## Beams Week in Review

| Store | Initial Luminosity | Duration | Termination | Comments |
| --- | --- | --- | --- | --- |
| 1845 | 3.09E31 | 9.3 |  intentional | 143 mA, no known changes |
| 1863 | 2.52E31 | 15.5 | intentional | 96 mA , kicker timing, MI rpos attn |
| 1865

18xx

18xx | 3.38E31

0.0

0.0 | 9.7

0.0

0.0 | RF trip (lightning ?)
Quench A11

Quench A11 | 134 mA, dampers off |
| 1886 | 3.50E31 | 22.0 | intentional  | 141 mA,tev tunes,coupling,orbits |

- All Experimenters Meeting

- 21 October 2002

## Peak Luminosity

- All Experimenters Meeting

- 21 October 2002

## Weekly Integrated Luminosity

- All Experimenters Meeting

- 21 October 2002

## Integrated Luminosity

- All Experimenters Meeting

- 21 October 2002

## Beams Week in Review

- Current Near Term Issues
- Proton and pbar emittance preservation
- Proton and pbar lifetime at pbar injection
- Proton and pbar lifetime on the ramp
- Pbar coalescing with large stacks, 85% 140 mA stack

- All Experimenters Meeting

- 21 October 2002

## Schedule for this week

-  Focused Required Maintenance (8 hr)
- Minimize impact on luminosity
- Put in Tevatron store to last till Tuesday
- Pbar maintenance Monday then stack overnight till 0600 Tuesday and sit on stack during Tuesday access.
- Booster, MI, Tev,  Cryo  maintenance start Tuesday 0600 – 1500
- CDF/D0 access start 0400 Tuesday
- Remainder of week Stack ‘n Store

- All Experimenters Meeting

- 21 October 2002

## Schedule for this Week

- All Experimenters Meeting

- 21 October 2002

## Longer-term schedule

- Week 10/28
- Stack ‘n Store  (No planned dedicated studies/access)
- Potential short between stores studies and *End of Store* studies
- Shots to Recycler - off the bottom and small stack dedicated, *depending on Collider operation*
- Week 11/4
- Stack ‘n store
- Accelerator studies (?)
- Week 11/11
- Stack ‘n Store
- Necessary Repairs (?)

- All Experimenters Meeting

- 21 October 2002