# Presentation: 846821

## Targetry Concept for a Neutrino Factory

-             EMCOG  Meeting
-                  CERN
-         November 18, 2003

##  Intense Proton  Sources 

- World wide interest in the development of new proton drivers
- New physics opportunities are presenting themselves
-  Neutron Sources
- European Spallation Source
- US Spallation Neutron Source
- Japanese Neutron Source
- Kaons
- RSVP at BNL
- KAMI at FNAL
- Muons
- MECO and g-2 at BNL
- SINDRUM at PSI
- EDM at JPARC
- Muon Collider
- Neutrinos
- Superbeams
- Neutrino Factories

## Multi-MW New Proton Machines

- SNS at 1.2 MW                     2.0 MW
- JPARC 0.7 MW                    4.0  MW
- FNAL   0.4 MW                    1.2 MW              2.0 MW
- BNL     0.14 MW                  1.0 MW              4.0 MW

**AGS Upgrade to 1 MW **

## High-power Targetry Challenges

-  High-average power and High-peak power issues
- Thermal management
- Target melting
- Target vaporization
- Thermal shock
- Beam-induced pressure waves
- Radiation
- Material properties
- Radioactivity inventory
- Remote handling

##           High-power Targetry Ronkonkoma, Long Island Sept. 2003

-  New physics opportunities are demanding more intense proton drivers.
-  1 MW machines are almost here!  4 MW machines are planned.
-  Targets for 1 MW machines exist but are unproven.
-  But no convincing solution exists yet for the 4 MW class machines.
-  Worldwide R&D efforts to develop targets for these new machines.
-  A key workshop concern was the lack of worldwide support facilities where promising new ideas can be tested.

##  Neutrino Factory and Muon Collider                             

-  Neutrino Factory
- Key parameter is neutrino flux
- Source strength is pre-eminent issue
- Maximize protons-on-target in order to maximize pions/muons collected
- Muon collider
- Gain in luminosity proportional to the square of source strength
- Small beam cross-sectional area (beam cooling) is also important

## Neutrino Factory Targetry Concept

- Capture low PT pions in high-field solenoid
- Use Hg jet tilted with respect to solenoid axis
- Use Hg pool as beam dump

- Engineered solution--P. Spampinato, ORNL

## Achieving Intense Muon Beams

- Maximize Pion/Muon Production
- Soft Pion Production
- Higher Z material
- High energy deposition
- Mechanical disruption
- High Magnetic Field

## High-Z Materials

**Key Properties**
- Maximal soft-pion production
- High pion absorption
- High peak energy deposition
- Potential for extension beyond 4 MW (liquids)
**Key Issues**
- Jet dynamics in a high-field solenoid
- Target disruption
- Achievement of near-laminar flow for a 20 m/s jet

## E951 Hg Jet Tests

** ****1cm diameter Hg Jet **
** ****24 GeV 4 TP Proton Beam**
** **_**No**_** Magnetic Field**

## CERN Passive Hg Thimble Test

- Exposures to a BNL AGS 24 GeV
- 2 TP beam.  T=0, 0.5 , 1.6 and 3.4 ms.

## CERN Hg Thimble Results

- Simulations—Prykarpatskyy, BNL

- Bulk ejection velocity as a function
- Of beam spot size.  ISOLDE data is
- 17 TP at 1.4 GeV.

## Key E951 Results

-  Hg jet dispersal proportional to beam intensity
-  Hg jet dispersal ~ 10 m/s for 4 TP 24 GeV beam
-  Hg jet dispersal velocities ~ 1⁄2 times that of “confined thimble” target
-  Hg dispersal is largely transverse to the jet axis -- longitudinal propagation of pressure waves is suppressed
-  Visible manifestation of jet dispersal delayed 40 s

## CERN/Grenoble Hg Jet Tests

** ****4 mm diameter Hg Jet **
** ****v = 12 m/s**
** ****0, 10, 20T Magnetic Field**
** **_**No**_** Proton Beam**

- A. Fabich, J. Lettry
- Nufact’02

## Key Jet/Magnetic Field Results

- The Hg jet is stabilized by the 20 T magnetic field
- Minimal jet deflection for 100 mrad angle of entry
- Jet velocity reduced upon entry to the magnetic field

## Simulations  at BNL (Samulyak)

- Gaussian energy deposition profile
- Peaked at 100 J/g. Times run from
- 0 to 124 s.

- Jet dispersal at t=100 s with magnetic
- Field varying from B=0 to 10T

## Bringing it all Together

- We wish to perform a proof-of-principle test which will include:
- A high-power intense proton beam (16 to 32 TP per pulse)
- A high (> 15T) solenoidal field
- A high (> 10m/s) velocity Hg jet
- A ~1cm diameter Hg jet
- Experimental goals include:
- Studies of 1cm diameter jet entering a 15T solenoid magnet
- Studies of the Hg jet dispersal provoked by an intense pulse of a proton beam in a high solenoidal field
- Studies of the influence of entry angle on jet performance
- Confirm Neutrino factory/Muon Collider Targetry concept

## High Field Pulsed Solenoid

-   70o K Operation
-   15 T with 4.5 MW Pulsed Power
-   15 cm warm bore
-   1 m long beam pipe

- Peter Titus, MIT

## Pulsed Solenoid Performance

**5T Peak Field with 2 inner coils; 540 KVA ; 80****O**** K**
**10T Peak Field with 2 inner coils; 2.2 MVA PS; 72****O**** K**
**15T Peak Field with 3 coils; 2.2 MVA PS; 30****O**** K**
**15T Peak Field with 3 coils; 4.4 MVA PS; 70****O**** K**

## Possible Target Test Station Sites

- Accelerator Complex Parameters:

| Parameter | BNL
AGS | CERN
PS | RAL
ISIS | LANCE
WNR | JPARC
RCS | JPARC
MR |
| --- | --- | --- | --- | --- | --- | --- |
| Proton Energy, GeV | 24 | 24 | 0.8 | 0.8 | 3 | 50 |
| p/bunch, 1012 | 6 | 4 | 10 | 28 | 42 | 42 |
| Bunch/cycle | 12 | 8 | 2 | 1 | 2 | 9 |
| p/cycle,  1012 | 72 | 32 | 20 | 28 | 83 | 300 |
| Cycle length, s | 2.2 | 2.0 | 0.3 | 0.25 | 0.6 | 4.2 |
| Availability (?) | 07 | 06 | 06 | Now | 08 | 09 |

## Possible Targetry Test at JPARC

- Letter of Intent submitted January 21, 2003 – presented June 27, 2003

## Target Test Site at CERN

## Possible Experiment Location at CERN

- Letter of Intent to submitted Oct. 23, 2003

## Letter of Intent-- Isolde and nToF Committee

- Participating Institutions
- RAL
- CERN
- KEK
- BNL
- Princeton University

## The TT2a Beam Line

- We propose running without longitudinal
- bunch compression allowing for a reduced
- beam spot size of ~ 2mm rms radius.

##    Original Cryogenic Concept  at BNL 

-  BNL specific  solution
-  Heat exchanger
-  LH2 or LN2 primary   cooling
-  Circulating gaseous He secondary cooling

## Simplified Cryogenic System

## Battery Power Supply R&D

- Battery/Charger
- 12V  1400A

- Mech. Switch
- 1500V 1600 A

- IGCT 600V 4000A

- Mechanical Switch capable
- of 4.4 MW Pulsed System

- Load

- IGCT 600V 4000A

## Battery Power Supply (Cont)

- Mechanical Switch capable
- of 4.4 MW Pulsed System

## Pulsed Solenoid  Project Cost Profile 

- Magnet
-         Fabrication        $ 410 K
-         Monitoring        $   80 K
-         Testing              $   90 K
-         Shipping            $   15 K
- Cryogenic System (LN2 without Heat Exchanger)
-         Cryo                 $ 300 K
- PS (Battery array with switching/charging/bussing)
-         PS System        $ 460 K
- Total Project  Cost  $1355 K