# Presentation: 493026

## MANX Update

- Mary Anne Cummings
- Steve Kahn
- Muons, Inc.

## MANX Collaboration     

- Robert Abrams1, Mohammad Alsharo’a1, Charles Ankenbrandt2, Emanuela Barzi2,
- Kevin Beard3, Alex Bogacz3, Daniel Broemmelsiek2, Alan Bross2, Yu-Chiu Chao3,
- Mary Anne Cummings1, Yaroslav Derbenev3, Henry Frisch4, Stephen Geer2,
- Ivan Gonin2, Gail Hanson5, Martin Hu2, Andreas Jansson2, Rolland Johnson1,
- Stephen Kahn1, Daniel Kaplan6, Vladimir Kashikhin2, Sergey Korenev1,
- Moyses Kuchnir1, Mike Lamm2, Valeri Lebedev2, David Neuffer2, David Newsham1, Milorad Popovic2, Robert Rimmer3, Thomas Roberts1, Richard Sah1, Vladimir Shiltsev2, Linda Spentzouris6, Alvin Tollestrup2, Daniele Turrioni2, Victor Yarba2,
- Katsuya Yonehara2, Cary Yoshikawa2, Alexander Zlobin2
- 1*Muons, Inc.*
- 2*Fermi National Accelerator Laboratory*
- 3*Thomas Jefferson National Accelerator Facility*
- 4*University of Chicago*
- 5*University of California at Riverside*
- 6*Illinois Institute of Technology*
**http://www.muonsinc.com/tiki-download_file.php?fileId=230**

## MANX  Motivations    

**Demonstrate **
- Longitudinal cooling
- 6D cooling in cont. absorber
- Prototype precooler
- Helical Cooling Channel
- Engineering concepts to accommodate RF for later demos or cooling channel prototypes
- New technology

- PROS:
-    Avoids H2 safety problems
-    No RF in the MANX HCC
- CONS:
-    Avoids H2 safety problems
-    No RF in the MANX HCC

## Ionization cooling	issues

- and
- Figure of merit: Fcool=LRdE/ds
- (4D cooling) for different absorbers

- Ionization cooling	issues

- Slope of dE/dx too small for longitudinal cooling  if p>300 **Want ****β****┴****≈p/B as small as possible**
- Reducing p difficult as the slope of dE/dx    implies longitudinal heating for p<300.
- Synchrotron motion then makes cooling channel design more difficult.
- Can compensate with more complex **dispersion function** or absorber shape
- Increasing B means **new technology**

## HCC theory evolution

- Positive dispersion

- Dipole   Dipole + Solenoid  (+Quad for stability)

- }

- Transforming to the frame of the rotating helical dipole leads to a time and z –independent Hamiltonian, can form relation:

**Manipulate values of parameters to**
**change performance:**

- Equal cooling decrement

- Longitudinal only cooling decrement

## HCC Applications

*Solenoid + High Pressurized RF*

- Precooler

- Series of HCCs

- As a cooling channel (abs+RF):

- As precooler:
- absorber, no RF.

- As a decay channel (no absorber):

- Some examples of parameter manipulation from the derbenev-johnson HCC theory to address specific applications:

**Muons, Inc. : ****Nothing designed today will be used exactly as imagined now**** **

- Stopping muons: decreasing absorber density.

## Another HCC: A MANX channel

- Use Liquid He absorber
- No RF cavity
- Length of cooling channel: 3.2 m
- Length of matching section: 2.4 m
- Helical pitch k: 1.0
- Helical orbit radius: 25 cm
- Helical period: 1.6 m
- Transverse cooling: ~1.3
- Longitudinal cooling: ~1.3
**6D cooling: ~2**

- G4BL Simulation

| Initial mean momentum:
Final meam momentum | P | 300 MeV/c
170 MeV/c |
| --- | --- | --- |
| Helical pitch: |  | 1 |
| Helical period: |  | 1.6 m |
| Helical ref. orbit radius: | a | 0.255 m |
| Initial solenoid strength:
Final solenoid strength: | Bz | -3.8 T
-1.7 T |
| Initial helical dipole strength:
Final helical dipole strength:  | b | 1.2 T
0.8 T |
| Initial helical quad. strength:
Final helical quad. Strength:  | b’ | -0.9 T/m
-0.5 T/m |

## MANX HCC Design Evolution

- Combined function magnets:
-     1. Layered conductors for individual     components
-     2. Individual coils, offsets create
-         dipole, quad components

- 1.“Conventional”

- 2.“Kashikhin”

**Can in principle use coil offsets to construct**
**any desired magnetic channel: HCC, matching, etc.**

## Possible MANX configurations

*August 8, 2007*

*AAC'07 K. Yonehara*

-  Helix period = 1.2 m
-  Coil length = 0.05 m
-  Gap between coils = 0.01 m
-  Current = -430.0 A/mm2
- (VK ‘s original value= -330.0 A/mm2)

- Increase gap between coils
- from 20 mm to 100 mm

- HCC

- Matching

- Matching

**Design HCC Magnet**

## Feasibility of RF in MANX

**Starting from the original cooling channel design:**

**Adapting to variations of HCC:**

- Limited by longitudinally spacing,
- However I believe that this is workable for MANX parameters

- Limited by radially spacing
- Forced to higher frequency

- Requires lots of RF cavities

## Feasibility of RF in MANX (cont.)

- The third option for RF:  Interleave banks of RF cavities after MANX-like cooling segments to replace energy loss.
- This is probably the easiest from an RF engineering point of view.
- It allows significant swings in particle energy.
- This makes cooling performance more difficult.
- This has not been successfully simulated as yet.
- This requires more difficult matching than either of the two previous schemes.
- The matching is not symmetrical for entering and exiting the RF.
- The RF must be put inside (or outside) solenoid coils, since we must hold the beam together in the RF.

## MANX following MICE 

**Attempt to construct HCC and matching fields directly from individual**
**Coils in “G4MANX”, using the MICE spectrometers.**

## Current Simulation Status

- The current G4MANX simulation does show significant *transverse *cooling.  (See figure).  Cuts require:
- The muon is seen downstream.
- The muon is inside the magnetic channel.
- This is partly responsible for the unexpectedly small emittance in the upstream matching region.
- This simulation unfortunately shows *longitudinal *and *6D *emittance growth (intentionally not shown) due to energy spread.
- This is being investigated.

**Inside Cryostat**

**Matching**
**Region**

## The MANX/FNAL APC Roadmap to 2012

- No

- No

- Yes

- Plan A

- Plan B

- 2008 ~ 2011
- - No RF
-  LHe
- + Cooling

- 2009 ~ 2011
- + RF
- + GH2
- - Cooling

- We will be in competition against
- CLIC at 2012.

## R & D Toward MANX/HCC Cooling..

**Detectors:**
- “0th” order study MANX is with the MICE detectors.
- Studies at FNAL by Martin Hu for cryo operation of scin. fibers
- New detector proposals:
- Multi-Pixel Photon Counters For Particle Detection Systems (new phase I 2008 proposal submitted to DOE SBIR)
- Fast timing detectors ~ few ps resolution with U Chicago
**RF**
- MTA beam test is scheduled for HPRF at FNA
**HCC Ring Tests**
- Four Ring Test.
- Demonstrate individual ring field reproducibility.  This is an important component of the field quality.
- Supported by FNAL and Muons, Inc. PH II
**Simulations**
- Continue studies of HCC optimization
- Extension to G4BL for resolutions, systematics and controls studies
- “G4MANX” program based on “G4MICE” for complete reconstruction

## MANX Near Future

- THIS IS HAPPENING...
- FNAL has put muons on the agenda
- Impressive groups of persons involved on projects
- MTA beam test is a priority
- HCC theory is being simulated and refined:
- RF studies informing HCC MANX design
- New insights into isochronicity (gamma-t) are being investigated and exploited
- HCC coil tests planned and implemented
- Serious engineering concerns on Manx HCC being addressed
- Muons, Inc. joining MICE – natural collaborators, many similar problems