# Presentation: 304476

## Proton Plan 

**Eric Prebys, FNAL Accelerator Division**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Charge

**Develop a plan for a reasonable set of improvements and operational initiatives to  maximize proton delivery to NuMI and the Booster Neutrino Beam (BNB) over the next ten years or so.**
**Estimate the budget and timeline for these improvements.**
**Estimate proton delivery to both beam lines if the Plan proceeds on schedule.**
**Note:  this plan is *****exclusive***** of the Proton Driver, which we assume will one day replace the existing Proton Source (Linac+Booster).**
**Note: not *****yet***** fully updated to reflect BTeV decision**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Machines of the Proton Plan

- Linac:    0-400 MeV    15 Hz

- Booster:    .4-8 GeV    15 Hz      (instantaneous)

- Main Injector:    8-120 (150) GeV    1.4 sec

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Phased Approach to Neutrino Program

**Phase 0 (now):**
- Goal: deliver 2.5E13 protons per 2 second MI cycle to NuMI (~2E20 p/yr), limited by MI RF system.
- Deliver 1-2E20 protons per year to Booster Neutrino Beam (currently MiniBooNE)
**Phase 1 (~2008):**
- A combination of Main Injector RF improvements and operational loading initiatives will increase the NuMI intensity to 4-5E13 protons per 2.2 second cycle to NuMI (~3E20 p/yr).
- This will increase by ~20% as protons currently used for pbar production become available.
- It is hoped we can continue to operate BNB at the 2E20 p/yr level during this period.
**Phase 2 (post-collider):**
- In this phase, we will consider using the recycler as a preloader to the Main Injector and possibly reducing the Main Injector cycle time.
- The exact scope and potential of these improvements is under study.
**Phase 3 (proton driver)**
- Main Injector RF must accommodate 1.5E14 protons every 1.5 seconds
- NuMI beamline and target must also be compatible with these intensities.

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## What Limits Total Proton Intensity?

**Maximum number of Protons the Booster can stably accelerate: ****5E12**
**Maximum average Booster rep. Rate:  ****currently 7.5 Hz****, ****may have to go to 10 Hz for NuMI+ *****(full)***** MiniBooNE**
**(NUMI only) Maximum number of booster batches the Main Injector can hold: ****currently 6 *****in principle*****, ****possibly go to 11 with fancy loading schemes in the future**
**(NUMI only) Minimum Main Injector ramp cycle time (NUMI only): ****1.4s+loading time**** (at least 1/15s******nbatches*****)**
**Losses in the Booster:**
- Above ground radiation
- Damage and/or activation of tunnel components

*Our biggest worry at the moment and probably forever*

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Plan Strategy

- See full document: **BEAMS-DOC-1441**
- Increasing the proton delivery from the Booster to NuMI and MiniBooNE
- Increase maximum average Booster repetition rate.
- Increase acceptance by improving orbit control and beam quality.
- Increasing the beam intensity in the Main Injector for NuMI
- Main Injector multi-batch operation.
- Slip stacking in Main Injector (requires RF upgrade).
- Improving operational reliability and radiation limitations
- Linac quad supplies
- Booster and Linac Instrumentation
- Booster RF Upgrade
- Investigate 7835 Problem

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Breakdown of Plan

| WBS | Description |
| --- | --- |
| 1 | Proton Plan |
| 1.1 | Linac Upgrades |
| 1.1.1 | Linac PA Vulnerability |
| 1.1.2 | Linac Quad Power Supplies |
| 1.1.3 | Linac Instrumentation Upgrade |
| 1.2 |  Booster Upgrades |
| 1.2.1 | Determination of Rep Rate Limit |
| 1.2.2 | ORBUMP System |
| 1.2.3 | Corrector System |
| 1.2.4 | 30 Hz Harmonic Upgrade |
| 1.2.5 | Gamma-t System |
| 1.2.6 | Alignment Improvements |
| 1.2.7 | Drift Tube Cooling |
| 1.2.8 | Booster RF Cavity #20 |
| 1.2.9 | Booster Solid State RF PA’s |
| 1.2.10 | Booster Instrumentation Upgrade |
| 1.3 | Main Injector Upgrades |
| 1.3.1 | Large Aperture Quads |
| 1.3.2 | Main Injector Collimator |
| 1.3.3 | NuMI Multi-batch Operation |
| 1.3.4 | Main Injector RF Upgrade |
| 1.4 | Management |

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Review: Main Injector Loading

**The Main Injector has six usable “slots”, into which Booster batches may be placed.**
**More batches may be loaded, using “slip stacking”, in which batches are injected at slightly different energy, drift together, and are captures as one batch (with at least twice the longitudinal emittance).  **

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Main Injector Loading (cont’d)

**Initial NuMI operation (“2+5”):**
- Two batches will be slip stacked for antiproton production.
- Five more batches will be loaded for NuMI
- All will be accelerated together.
**Ultimate NuMI operation (“2+9”):**
- Five batches will be loaded into the Main Injector, leaving one empty slot.
- Six more batches will be loaded and slipped with the first to make two for antiproton production and 9 for NuMI.
- This is beyond the capacity of the current RF system.

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Main Injector RF 101

**Our present system:**
- Number of cavities: 18
- Total Power Available: 175 kW/cavity (single PA)
- Total Power dissipated: 58.6 kW/cavity
- Power available for acceleration: 116.4 kW/cavity
- Maximum acceleration rate: 200 GeV/s
**In the absence of beam loading compensation, an RF system is stable until the energy expended in accelerating the beam is *****equal***** to the energy dissipated in the cavity.**
**Feed forward loops can increase this stability threshold**
**For our system**
- Maximum guaranteed stable intensity: 3.3E13 protons
- Power limited intensity: 6.5E13 protons

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Options

**By adding an additional (175/2 – 58.6 =) 28.9 kW passive load to each cavity, we could ensure 87.5 kW of power for stable acceleration**
- 4.9E13 proton per batch limit
**Each cavity has an additional port for a second PA, potentially giving 350 kW of total power.**
**This could potentially give**
- 9.8E13 protons/batch in the most conservative case (175 kW power dissipation)
- Possibly higher with feedback loops

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Proton Projections

**Phases of Operation**
- Phase I
- After this shutdown
- Dogleg problem ameliorated
- Booster limited to 7.5Hz total repetition rate
- Main Injector limited to 4E13 protons (2+5 operation)
- Phase II
- After 2005 shutdown
- ORBUMP replaced
- RF cooling finished
- Booster capable of 9Hz operation
- MI still limited
- Phase III
- After 2006 shutdown
- MI RF upgrade complete
- 2+9 operation to NuMI

- 2007

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Predicted Peak Proton Intensity Limits

- Actual

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Calculating NuMI PoT

**Even the fallback scenario accommodates NuMI operation.**
**Assume the following**
- Booster batch intensity rises steadily to 5.5E12 over the next three years.
- Ramp up to full 2+5 operation by April 2005
- Ramp up to full 2+9 batch slipstacked operation a few months after MI RF upgrade.
- 90% efficiency for slip stacking.
- 10 month operation each year.
- 81% total uptime for remainder of year
- based on MiniBooNE. Includes scheduled and unscheduled downtime
- 90% avg/peak operating efficiency
- 10% down time for shot setup
- 5% down time for fast Recycler transfers
- 5% down time during 2005 for Ecool accesses.
- Does NOT include SY120

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Machine Loading

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## “Design” PoT

|  | Booster
Batch Size | Main Injector Load | CycleTime | MI Intensity | Booster Rate* | Total Proton Rate | Annual Rate at  end of Phase |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  |  | (AP + NuMI) | (sec) | (protons) | (Hz) | (p/hr) | NuMI | BNB |
| Actual Operation |  |  |  |  |  |  |  |  |
| July, 04 | 5.0E+12 | 1+0 | 2.0 | 0.5E+13 | 5.1 | 0.8E+17 | 0 | 3.3E+20 |
| Proton Plan |  |  |  |  |  |  |  |  |
| Phase I | 5.10E+12 | 2+12+5 | 2.0 | 3.6E+13 | 6.3 | 1.0E+17 | 2.0E+20 | 1.5E+20 |
| Phase II | 5.3E+12 | 2+5 | 2.0 | 3.7E+13 | 7.5 | 1.2E+17 | 2.2E+20 | 2.8E+20 |
| Phase III | 5.50E+12  | 2+9 | 2.2 | 6.0E+13 | 8.3 | 1.5E+17 | 3.4E+20 | 2.2E+20 |
| Beyond Scope of Present Plan |  |  |  |  |  |  |  |  |
| 11 Hz | 5.50E+12 | 2+9 | 2.2 | 6.1E+13 | 11.0 | 2.0E+17 | 3.4E+20 | 5.0E+20 |

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Current Budget Guidance

**The cancellation of BTeV has resulted in a fairly generous funding profile for this plan.**
**The most likely scenario:**
- Main Injector RF project and Booster Corrector System get delayed by one year, relative to the original plan.
- Booster RF Solid State PA upgrade deferred indefinitely.

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Projections (“delayed” scenario in document)

- BNB only runs during shot setup

- NuMI turn-on overly optimistit

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Conclusions

**We have proposed a set of accelerator improvements to maximize protons to NuMI and the 8 GeV line.**
**Over the next three years or so, these will give the capability of**
- ~7.4E16 p/hr to NuMI (~3.4E20 p/yr)
- Excess capacity of ~4.5E16 p/hr (2E20 p/yr) for the 8 GeV line.
**The NuMI numbers will immediately go up by ~20% after the end of the collider program.**
**We are investigating more aggressive plans to increase Main Injector throughput during that era.**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Extra Slides for Questions...

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Status of Major Work

**Linac**
- 7835 Task force
- Burle OK for now
- Buy tubes (12 extra by end of 06)
- LEL quad power supplies
- Working on prototype, based on HEL supplies
**Booster:**
- ORBUMP magnets:
- First magnet built and tested, proceeding with the rest
- ORBUMP PS:
- Procuring and assembling
- Corrector System
- Conceptual design complete
- Working on detailed design
- Working on PS specs

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Status of Major Work

**Main Injector**
- Large Aperture Quads
- In fabrication.  Will be ready for 05 shutdown
- 5-batch commissioning
- In progress
- Loss mitigation/collimator system
- Working group formed
- Identifying collimator candidates for MI-8
- Starting ring collimator system design based on Booster
- Miscellaneous projects (added since first draft)
- Barrier bucket cavity:
- In procurement
- Injection kicker modification:
- Being designed

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Status of MI RF Work

**Build prototype cavity**
- Passive load:
- Existing port?
- Cut new port?
- Second PA
**Carry out a series of studies in the Main Injector**
- Determine effectiveness of feed-forward loops
- Determine optimal passive load and predict intensity limit for one- and two- PA scenarios
**Refine cost estimate for passive load and PA upgrades.**
**Use this information to determine longer range plan.**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Status of Plan

**Working with Project Support to complete WBS chart.**
**All major elements at least have reasonably accurate placeholders.**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Evaluate Effect of Booster Improvements

**Calculate effect of various improvments based on increased acceptance (a la McGinnis):**
**Use:**

- Effective aperture reduction

| Condition | Date | A | max D | max beta | Acceptance | Relative |
| --- | --- | --- | --- | --- | --- | --- |
|   | Completed | (mm) | (m) | (m) | (-mm-mr) | Increase (%) |
| Start of MiniBooNE | --- | 10 | 6.2 | 45.8 | 15.7 | -15 |
| Dogleg 3 Fix | Oct-03 | 10 | 4.5 | 40.8 | 18.4 | 0 |
| Dogleg 13 Fix | Oct-04 | 10 | 3.8 | 36.1 | 21.0 | 14 |
| Alignment | Oct-05 | 8 | 3.8 | 36.1 | 24.3 | 32 |
| ORBUMP | Oct-05 | 5 | 3.8 | 36.1 | 29.5 | 60 |
| correctors | Oct-06 | 2 | 3.8 | 36.1 | 35.2 | 92 |
| Ideal | --- | 0 | 3.19 | 33.7 | 42.3 | 130 |

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Effect on Max Proton Intensity

**Prior to this shutdown, regularly delivering 7.5E16pph with ~40% reduction in activation around most of the Booster.**
- Assume after another year of tuning and collimator optimization, we could have hit 1E17 pph with no other improvments (“fallback” = .9E17).
**Operational experience: tuning asymptotically approaches benefit of a particular improvement:**
- Assume after one year of tuning, 50% of the benefit of a particular improvement is realized (fallback = 25%).

| Date | “Design” Limit(1E16 p/hr) | FallbackLimit(1E16 p/hr) | Comment |
| --- | --- | --- | --- |
| 1/2006 | 10.7 | 9.3 | Effect of collimators, dogleg fix, plus some alignment |
| 1/2007 | 13.0 | 10.4 | Alignment and ORBUMP |
| 1/2008 | 14.6 | 11.0 | New corrector system |

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Estimating PoT

**Even the fallback proton scenario accommodates NuMI operation.**
**Total proton output continues to be limited by radiation losses, rather than Booster repetition rate.**
**We assume:**
- NuMI and antiproton production get what they need
- The BNB gets whatever it can beyond that, within the total output limit of the Booster
**This is a programmatic decision:**
- Protons can be diverted from NuMI to the BNB, but not the other way around.
**The BMB PoT estimates are extremely sensitive to the total proton limit, which is uncertain.**

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## Calculating BNB PoT

**Trickier:**
- Still limited by beam loss, NOT rep. rate.
- Assume antiproton and NuMI have priority, so
- BNB VERY sensitive to proton limit and its fluctuations.
**Use:**
**	****(avg pph) = (pph lim.)*****η**** – (NuMI pph) – (pbar pph)**
**Also assume:**
- 10 month operation
- 81% up time (based on 2004)
- 5% downtime in 2005 for ECool access
- BNB gets all the beam during shot setup (10% of the time)

- Avg/pk ~ 86% from July 2004 MiniBooNE operation

- Booster output limit, as discussed

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005

## “Design”  Totals (outdated)

- Last 4 weeks

- Prebys  - Proton Driver Director's Review

- March 15-17, 2005