# Presentation: 512861

## Proton Drivers & Muon Sources at Fermilab

**David Neuffer**
- Fermilab

## Introduction–Fermilab Future Plans (~Oddone)

**(Tevatron shuts down ~2009)**
**First Priority – ILC**
**Global Study ~1 year –present to DOE  (end of 2006)**
- IF **favorable, push for near-term construction at Fermilab**
**Second Priority – ****protons**
**Priorities are NUMI, NoVA, ...**
**Some excess proton capacity for other experiments**
**If ILC near-term, continue facility incremental upgrades**
**Becomes high priority if ILC not encouraged **
- PROTON DRIVER:** 8 GeV, MW superconducting linac**
**Accelerator Physics Center (from FRA bid)**
**Muon Collider Task Force**

## Fermilab proton sources

**Adapt existing facility for “Super” NUMI  and ****μ****-e ****conversion experiment**
- Future “upgrades”- configurations- up to~1MW at 125 GeV
- Protons for muon source – A-D configuration
- extract beam for mu-e conversion
**Proton Driver – 8 GeV future source ?**
- 1 to 4 MW at 8 GeV SRF Linac
- for collider,  ν-Factory, etc.
- Need buncher ring to accumulate p’s

## Present Proton Source: 8 GeV Booster

**NOW:** 400 MeV Linac8 GeV Booster**    (C=454m)**
**	****produces 80 bunches (53 MHz)**
- Currently Limited by losses** in Booster**
- ~8Hz, ~ 4  1012/ pulse: ~3×1020 p/year (0.04MW)
**15Hz, **** ****5 ******** 10****12****/pulse possible (0.1MW) (6********10****13**** protons/s) **
- NUMI,** MiniBOONE, Tevatron ****p-****source**
**Tevatron, MiniBOONE will be completed... **
**Capacity for other experiments ...**
**But 15Hz cycle limits applications **

**Linac – 400MeV**

**Booster – 8 GeV**

**Main Injector,**
**MiniBOONE**

## NewRing (P)

**Proton Linac (****H****-****)**
**     ****8 GeV?**

**NewRing (P)**

**H****-**

**t**

- 8 GeV f
- Proton sources

## SNuMI stage 1: 700 kWRecycler as an 8 GeV proton pre-injector

-  **After the Collider:  Use the Recycler as a p pre-injector**
** ****Booster batches are injected at 15 Hz rep rate to fill Recycler, **
** ****transferred to MI and accelerated **
** ****if we use the Recycler to accumulate protons from the Booster while MI is running, we can save 0.4 s for each 6 Booster batches injected**
** ****6 batches (5****×10****12**** p/bx) at 120 GeV every 1.467s ******** 390 kW**
** ****Recycler momentum aperture is large enough to allow “slip-stacking” in Recycler: up to 12 Booster batches injected**
** ****6 batches are slipped with respect to the other 6 and extracted to MI in a single turn**
** ****~4.7****×10****12 ****p/batch, 95% slip-stacking efficiency**
** ****5.4×10****13**** ppp at 120 GeV every 1.467 s ******** 700 kW**

**S. Nagaitsev, E. Prebys, M. Syphers ‘First Report of the Proton Study Group’, Beams-doc-2178**** **

## SNUMI stage 2: Use Accumulator

**After ~2009, accumulator and Debuncher, Recycler are not needed for Fermilab Collider**
**Can be used for proton programs**
**Accumulator could be used  for momentum stacking from booster for ~NUMI **
**Stacked beam could also be used for ****μ****-e **

| Parameter | Symbol | Accumulator | Debuncher |
| --- | --- | --- | --- |
| Circumference | C=2πRave | ~474m | 504m |
| Momentum | P | 8.89 GeV/c | 8.89 GeV/c |
| Transition γT | γT | 5.4 | 7.52 |
| betatron fns | βx, βy, η max | 47, 40, 9.6 | 19.8, 17, 2.2 |
| Tunes | νx, νy | 6.9, 8.9   | 9.65, 9.76 |
| aperture | a, b |  |  |

## Momentum stacking in Accumulator

**Accumulator stacks are boxcar stacked in Recycler; **
**6 accumulator stacks (18 booster fills) fills Recycler**
**Transfer to Main Injector for acceleration to 120 GeV **

##   “Superbeam” NEUTRINO PROGRAM + μ-source

**  “****Superbeam” NEUTRINO PROGRAM**** ****+ μ-source**

- Booster Batches

- Accumulator

- Recycler

- Debuncher

- 22 batches = 1. 467s MI cycle

- 4.61012 p/batch

- 44.61012 p/1467ms =  12.5 1012 p/sec

- 56 1012 p/sec

- 0.1s

- 1.367s

- NEUTRINO PROGRAM

- MUONS

- (NuMI +Muons)

- (NuMI)

- (Muons)

- (Alternative: 24 batches=1.6s MI cycle 11.5 1012 p/s)

- 1.08 MW of
- 120 GeV p

## ~ MECO PROPOSAL – adapted to Fermilab ...

**~ MECO PROPOSAL – adapted to Fermilab ...**

- Muon Beam Stop

- Straw Tracker

- Crystal Calorimeter

**Muon Stopping Target**

- SC Solenoid containing production target (5.0 T – 2.5 T)

- SC Detector Solenoid (2.0 T – 1.0 T)

- SC Transport Solenoid              (2.5 T – 2.1 T)

- 4  1020 primary protons
- at 8 GeV yield 1  1018
- stopping muons

- 8 GeV
- PROTONS

- Stop muons in a thin target and look
- for a single mono-energetic electron

**Pion production**
**& capture**

**Decay Channel****Momentum ****& sign****selection**

- Well developed design,
- reviewed for  cost & feasibility

- http://www.bnl.gov/henp/mu-e_docs/Draft_MECO_Tech_Prop.pdf

## BEAM REQUIREMENTS

**BEAM REQUIREMENTS**

- To reach MECO goal: Low energy bunched muon beam providing  ~1018 muons per yr: Requires ~1020 primary 8 GeV protons per yr.
- Bunch lengths short compared to the lifetime of muons in a nucleus (1.1 ms for Al), with a bunch spacing longer than this.
- Experimental signature: mono-energetic electron & nothing else.To minimize backgrounds, when there is no incoming primary beam there must be no beam at the level of 1 part in 109.
- _Ideal Bunch Structure for a MECO-like Experiment_:

**CW**

- << 1 s

- ~ 1 – 2 s

## Scenario overview

**Protons from Booster injected into accumulator**
**Stack 1 to 4 booster turns, debunch (w/extraction gap)**
**~4****·10****12 ****n****turns**** protons**
**Extract into Debuncher**
**Rebunch in Debuncher **
**to ~40ns rms single bunch **
**Slow extract to muon conversion experiment**
**over ~1.5s**

**Booster**

**Protons from Booster**

**Slow **
**extraction**

**Transfer to **
**Debuncher**

## Barrier bucket in Debuncher

**γ****T****=7.6- more isochronous **
**Needs less rf but more time****	**
**Compression within ~0.2s**
**A:Rf-14kV **barrier bucket
**Square wave rf**
**B: **h=4** rf 14 to 30 kV**
**Sinusoidal rf**
**~2.5 MHz**
**Start:±150°, σ****E ****= 3.3MeV**
**~4 batches**
******L****= 6****πσ****t****σ****E****= ~24 eV-s**
**Finish: σ < 30ns, σ****E ****= 42MeV**
**Small dilution**

## μtoe EXPERIMENT LOCATION:

**μ****toe ****EXPERIMENT LOCATION:**

- Detector

- Target

- Extracted
- Beam Line
- From
- Debuncher

- (Dixon Bogert)

- D50

**Experimental Area could also be used for other ****π****,****μ****, etc. experiments**** **

## Future Option:  f Proton Driver

**Fermilab may develop new proton source to replace “****8-GeV****” Booster at a multi-MW level**
- Studied at Fermilab but deferred to focus on ILC
- R&D continues on technology
- HINS – “High Intensity Neutrino Source” research
- deferral will be reevaluated as ILC develops ...
- Upgrade options
**8-GeV SRF proton linac **
**leading high-intensity possibility (HINS research)**
**Needs Collector ring for many applications **
- Booster-like rapid-cycling synchrotron but higher intensity
- Larger apertures, injection linac upgrade, deeper tunnel

## 2 MW Proton Driver Parameters (short list)

**8 GeV Superconducting LINAC  (1300 MHz rf)**

- Energy

**GeV**

**8**

- Particle Type

-     H- Ions, Protons, or Electrons

- Rep. Rate

**Hz**

- 2.5 to** ****10 **

- Active Length

- m

- 614

- Beam Current

- mA

- 25

- Pulse Length

- msec

- 3 to **1**

- Beam Intensity

**P / pulse**

**1.5E+14**

-  (can also be H-, P, or e-)

- P/s

- 1.5E+15

- Linac Beam Power

- MW avg.

**0.5 to 2**

- MW peak

- 200

## Review of the PD/Linac Cost

| (All costs in 2004 K$) | Linac |
| --- | --- |
| Project M&S* | 229,779 |
| Project SWF | 89,118 |
| Project Subtotal | 318,897 |
| G&A# 
(16.05% M&S & 30.35% Labor) | 63,927 |
| Project (incl. G&A) | 382,824 |
| Contingency (30%) | 114,847 |
| Total Cost | 497,670 |

- * Davis Bacon labor shows up as M&S
- # G&A rate will be lower on large POs

## HINS R&D

**Technology development toward Proton Driver**
**Build and test 325 MHz section of 8 GeV Linac**
**ion source, 2.5 MeV rfq, 10 MeV RT linac, 100 MeV SRF **

## HINS Front End - Beam Line Layout

- Ion source H-, LEBT	 				50 keV
- Radio Frequency Quadrupole		4-5 m, 		2.5 MeV
- MEBT 		(2 bunchers, 3 SC sol., chopper) 	4 m
- RT TSR section 	(16 resonators, 16 SC solenoid) 	10 m		10 Mev
- SSR1 section 	(18 resonators,  18 SC solenoids) 	14 m 		30 MeV
- SSR2 section  	(22  resonators, 12  SC solenoids) 	20 m 		90 MeV

**Frequency 325 MHz**
**Total length ~ 55 m **
***Limited by Meson Building***

- SSR1
- (=0.22)

- SSR2
- (=0.4)

- RT -CHSR

- MEBT

- RFQ

- IS

- W (MeV)

- 2.5

- 0.050

- 90

- 30

- 10

**Notes:**
Each system deserves a separate talk. I only can give a short overview of the key issues for each them.

## HINS Schedule 2006-2008

- 325 MHz RF power system, rf component tests
- July 2006
- Superconducting cavity test cryostat installation
- October 2006
- Ion Source installation in Meson Lab
- November 2006
- RFQ delivery and power testing
- January 2007
- 2.5 MeV beam tests
- Beginning February 2007
- First SC spoke resonator power tests in test cryostat
- April 2007
- Full 10 MeV RT linac installed; Beam operation
- April 2008
- First SC spoke resonator cryomodule installation
- October 2008
- Tests of RT + SC cavity RF distribution and control, 20 MeV Beam
- December 2008

## Meson Building Floor Plan

**60 MeV Linac**

**Klystron and Modulator Area**

**RF Component Test Facility**

**Cavity Test Cave**

**200 ft.**

**Ion Source and RFQ Area**

## NewRing (P)

**Proton Linac (****H****-****)**
**     ****8 GeV?**

**NewRing (P)**

**H****-**

**t**

- 8 GeV f
- Proton sources

**Transfer to debuncher**

## f APC program:  Collider

**Recent advances **
**Improved cooling scenarios **
**Muons, Inc.**** innovations**
**gas-filled rf cavities**
**“****Complete” cooling scenario**
**Potential high-energy  machine if ILC not enough energy ...**
**Cooling innovations may enable “low-emittance” collider**
**helical cooling channel**
**Parametric resonance cooling**
**Reverse emittance exchange**
**low-energy cooling**
**LEMC workshop Fermilab **
**Feb 12-16**

##  Collider Parameters

## Summary/Comments

**A proton source is important for Fermilab future**
**Proton source could be:**
**extension of existing facilities**
** ****New facility based on 8 GeV SRF Linac**
**Accelerator Physics Center:**

## New 8 GeV Accumulator/buncher/stretcher

**Type: **FODO racetrack,
- Superferric arcs
- nonscaling
**H****-**** injection into NewRing (10Hz)**
**700 turns**
**Transverse emittance can be enlarged (****ε****N ****=120π mm-mrad**** or more  ****20mm-mrad rms****)**
- Harmonic 4 buncher for ν-Factory, single bunch extraction (400ns spacing)
**single bunch extraction mode**
**Also useful for PRISM/PRIME, muon collider, ... **

| Circumference | C=2πRave | ~454m |
| --- | --- | --- |
| Momentum | P | 8.89 GeV/c |
| rf frequency,
Voltage | h=4
V0 | 2.6 MHz
<1MV |
| Slip factor | η=1/γ2- 1/γt2 | -0.022 |
| Tunes | νx, νy | 6.9, 8.9   |
| aperture | a, b | ~8, 5 cm |

**Linac injection**