# Presentation: 492510

## RSVP Beam Development and Pre-OperationsDRAFT

- RHIC/RSVP operation
- AGS high intensity performance
- RSVP beam requirements
- Beam development plan

## RHIC

**12:00 o’clock**

**2:00 o’clock**

**4:00 o’clock**

**6:00 o’clock**

**8:00 o’clock**

_***PHOBOS***_

**10:00 o’clock**

**RHIC**

**AGS**

**LINAC**

**BOOSTER**

**TANDEMS**

**NSRL (NASA)**

** ******** ****g-2**

**RSVP (NSF)**

**U-line**

**AGS/RHIC Accelerator Complex**

**Pol. Proton Source**

**High Intensity Source**

- Slow extraction

- Fast extraction

_**AGS:**_
- Intensity: 7  1013 protons/pulse
- Injector to RHIC:
- < 1 hours about every 4 hours

## AGS Peak Proton Intensities

**AGS Peak Proton Intensities**

- World record proton synchrotron intensity!

- 8  1013

- 6  1013

- 4  1013

- 2  1013

- 0

- Peak proton intensity

- With RHIC, no 2nd harmonic Booster cavity

## Total Accelerated Protons at the AGS

- Slow extracted beam (Kaon decay)
- Fast extracted beam (g-2)
- Note: Lower total accelerated protons in later years           due to much shorter running time

- With RHIC

## H- injection into the Booster

- 90 mA H-** **magnetron source
- High B dot gives effective longitudinal phase space painting.
- Injection period is approx. equal to synchrotron period.

- Simulation

- Measurement

**Injected:**
- 23  1012 ppb
- 1.3 eVs

**Circulating:**
- 17  1012 ppb
- 3.0 eVs

## AGS High Intensity Performance

- 6 single bunch transfers from Booster
- Peak intensity reached: 74  1012 ppp
- Bunch area:   3 eVs at injection                    10 eVs at extraction
- Intensity for FEB ops: 60  1012 ppp
- Strong space charge effects during accumulation in AGS
- 2nd order transition energy jumplimits available momentum aperture.
- Chromatic mismatch at transitioncauses emittance dilution

## High intensity bunch-to-bucket transfer

- Incoherent tune spread ~ 0.1  significant effects during beam accumulation

- Longitudinal emittance dilution at AGS injection through mismatch followed by smoothing with high frequency (93 MHz) cavity.
- Needed to avoid excessive space charge tune spread and coupled bunch instabilities.

- 200 ns

- Vertical difference

- Line density

- For 13  1012 ppb: coherent space charge tune shift varies along bunch: 0  ~ 0.1 at bunch center
- Dipole mismatch difficult to damp
- Quadrupole mismatch can cause halo

## RSVP requirements

**KOPIO:**
- 100  1012 ppp; 5.3 s cycle; extraction @ 25.5 GeV/c [20  1012 p/s ]
- Proton throughput achieved with g-2 FEB
- AGS injection energy upgrade to 2 GeV to reach 100 1012 ppp (R&D)
- Slow extraction with micro-bunching (200ps () every 40 ns)
- Extraction with high frequency cavity (25 MHz, 100 MHz) (R&D) < 250 ps every 10 ns demonstrated; no change in losses
- Extinction of 10-3 (R&D)
**MECO:**
- 40  1012 ppp;  1 s cycle; extraction @ 7.5 GeV/c [40  1012 p/s ]
- Increase throughput in Booster using rf beam loading compensation and loss control [from past operation expect ~ 24  1012 p/s] (R&D)
- Reduce AGS injection losses with MECO cycle (no transition crossing) (R&D)
- Slow extraction of 2 bunches with 10-9 extinction during 1.35 s gap.
- h=2 Booster operation; achieved 22  1012 protons per Booster cycle
- Two Booster cycles per AGS cycle
- Bunch merging to 2 bunches or develop h=1 Booster ops. (R&D)
- Gap cleaning with resonant transverse kicker plus rf kicker in beam line (R&D)

## Assumptions for Beam Development Plan

- RSVP Beam development will occur concurrent with RHIC physics running using “mode switching”
- Four year plan (FY06-09) to be ready for RSVP engineering runs in FY2010
- Use low intensity beam or high intensity beam with very low duty factor for beam development; data from instrumentation will be captured and analyzed before next beam shot
- Use external beam dumps whenever possible
- Most beam line/ detector development during FY08 - 09

## Timeline of Beam Development Plan

- FY06:(D-line available)9.6 weeks (concurrent with RHIC operation)
- 7.5 GeV/c AGS extraction to D line, MECO mini-bunching extraction commissioning
- Booster injection/acceleration efficiency tuning (h=1 vs h=2, localizing losses in Booster dump)
- FY07:(D-line available) 11.4 weeks (concurrent with RHIC operation)
- 7.5 GeV/c and 25.5 GeV/c extraction to D-line
- Booster-to-AGS efficiency tuning for MECO
- FY08:(AGS injection kicker, 25 MHz cavity, MECO and KOPIO beam lines) 30.6 weeks (concurrent with RHIC operation)
- Extraction to KOPIO, commission micro-bunching, specify 100 MHz cavity
- AGS injection efficiency at 2 GeV injection energy (new kicker)
- Extraction to MECO, further development of mini-bunching
- FY09: 28.1 weeks (concurrent with RHIC operation)
- Intensity development
- Additional beam line/detector development

## Detailed Beam Development Plan (1)

## Detailed Beam Development Plan (2)

## Conclusion

- RSVP beam development and pre-operations planned during RHIC physics running
- Beam requirements commissioned by RSVP engineering run (FY2010)
- Machine activation during beam development minimized with very low duty factor operation