# Presentation: 432230

## Run-5 Update

## Status: 3 weeks

- Total from January 11 (nbarn-1)
**Phenix:****	****	****4.49**
**STAR: ****	****	****4.58**
**Brahms:****	****	****2.01**
**Phobos: ****	****	****1.67**

## Production ramp: 37x37 4.5e9
No more emittance blow-up at transition  (Thomas)
Emittance end of ramp 15-17 pi (PLL on low excitation)
Transmission 90-94%
 Initial rates 40K+, 
	 Backgrounds under control 

Re-bucketing improvement  (2xMike, RF group)
Common cavities 

gap cleaning working on store (Angelika)
IPM, Schottky  improvements (Rob, Roger, Kurt)
RHIC Injection improvements (Wolfram)

Beam Experiments – spin-off
online matching works (Nikolay, Todd, Fulvia)
beta* measurements consistent with ~0.89 at star. ~1m at Phenix, ~2.5 at Brahms, ~2.8 at Phobos collision ratios (Mei)

- No more emittance blow-up at transition  *(Thomas)*
- Emittance end of ramp **15-17 pi** (PLL on low excitation)
- Transmission 90-94%
-  **Initial rates** 40K+,
- 	 **Backgrounds** under control* *
**Re-bucketing** improvement  *(2xMike, RF group)*
**Common cavities**
**gap cleaning** working on store *(Angelika)*
**IPM, Schottky  **improvements *(Rob, Roger, Kurt)*
**RHIC Injection** improvements* (Wolfram)*
- Beam Experiments – spin-off
**online matching** works *(Nikolay, Todd, Fulvia)*
**beta*** measurements consistent with ~0.89 at star. ~1m at Phenix, ~2.5 at Brahms, ~2.8 at Phobos collision ratios *(Mei)*

- Week 3 - Highlights

## Intensity/collisions – Week 3

- beamex

- Cogging
- losses

- 37x37 4.5e9

- Initial rates 40K+

## Gap cleaning is back

- Gap cleaning
- mid and end
- of  store

- continuous
- gap cleaning

- Emittance on
- store

- Bucket1

- Bunches with 4 collisions

- Bunch with 3 collisions

## Lumi develoment vs. flat running

- There is no such a thing as “flat running”: if there is no development, performance deteriorate, do not stay constant
- Discuss degree of development and lumi goals,
- 	amount of invested development time
- Detectors are limited by background (beam and collision related)
- Running machine for highest performance impacts reliability
- find optimum

## Intensity development

- Assuming *=0.90, emittance at the beginning of store 18
- Cu-Cu Xsection 2.6 barn, 37 bunches

| Bunch intensity
 at lumi | Transverse
Emittance (pi) | Initial collision rates (KHz) |
| --- | --- | --- |
| 4.2 | 18 | 42 |
| 4.5 | 18 | 48 |
| 4.8 | 18 (20) | 54  (49) |
| 5.1 | 18 (20) | 62  (55) |
| 5.4 | 18 (22) | 69  (57) |
| 5.7 | 18 (22) | 77  (63) |
| 6.0 | 18 (24) | 85  (64) |

## Running time and time

- Weather, power dips
- Accesses
- analysis of deviation from time estimates, “get personal”
- System problems
-      Failureops resetssupportsystem expertsystem expert drives in troubleshootingfixing
-     (identify possible improvements)
- Time between stores
- Data are collected by operation, sufficient stats to identify recurrent problems
- Time beginning of store
- Collider: goal 10 minutes (auto LISA+ auto-collimation)
- Phenix: ~25 minutes for clock change, STAR ~20-25 to turn on HV, etc.
- Any possible improvement there?

## Lumi Development

- _Next: optimization beginning of store_:
**BBA +  Orbit**, IR6, IR8, vertical Y rms (Todd, Vadim)
- New **‘lumi’ stone** after rebucketing (Steve)
- Automatic LISA **steering, collimation **(Angelika)
- IR corrections yellow
- _Strategy_
**Increase** **bunch intensity** to **5.5 e9**
*Increase progressively ****number of bunches***
*Commission ramp for ****new working point***