# Presentation: 014178

## FFAG cost optimization: 2.5-5 GeV Normal Conducting Ring

- C. Johnstone
- Muon Collaboration Meeting
- LBNL, Feb 13-17, 2005

## Muon FFAG Issues

- Number of turns  Phase-slip,
- Phase-slip  bend/cell;
-  the number of cells remains fixed
- for a fixed extraction/injection energy ratio (=2 for current designs)
- _independent of acceleration energy_
- Implications:
- Rings do not scale in cost with energy
- 2.5 – 5 GeV ring is 60-80% cost of 10 – 20 GeV ring
- A SC 2.5 – 5 GeV ring is not cost effective for only 2.5 GeV of acceleration

## Cost alternatives to 7T SC Rings:

- Lower SC fields : 7T  4T
- Single-turn vs. multiturn coils
- SC is still too expensive for lowest-energy, 2.5 – 5 GeV ring
- Low energy ring  15 Hz, Normal conducting
- 1.5 T peak poletip field
- 14 mil laminated magnets
- 15 Hz resonant power supply
- Cost estimates and designs exist based on large-acceptance proton driver designs by Chou, et. al. at Fermilab

## 2.5-5 GeV Normal Conducting FFAG

-                                           	             FDF-triplet
- Circumference                      	 	566m
- #cells                                     	100
- cell length                              	 5.663m
- rf drift				 2m
- D-bend length                        	 1.755m
- F-bend length                        	 0.454m  (2!)
- F-D spacing                          		 0.5 m
- Central energy                       	 5  GeV
- Peak poletip field			 1.5 T
- F gradient                              	11.6 T/m
- D gradient                              	  5.3 T/m
- F strength                                	 0.698
- D strength                               	 0.32
- Bend-field (central energy)        	1.8 kG
- Orbit swing
-        Low                                 	 -8.0
-        High                                  	    0
- C (pathlength)                      	  15.5 cm     10 turns
- (xmax/ymax) for 2.5, 5 GeV        ( 6.8/16.1)            ( 6.5/12.3)
- (x/y) 2.5 and 5 GeV                  (0.37/0.37)   (0.19/0.12)

## Cost estimates: Large-aperture PD Quadrupoles:1.2 m, 17.5 cm aperture, Tech Div. Fermilab

|  | Length = | 1.1 m |  |  |
| --- | --- | --- | --- | --- |
| Parts | Unit cost | Extended  |  |  |
| Steel |  $      0.65  |  $      5,659  |  | per pound typical price |
| Stamping |  $      0.50  |  $      6,478  |  | per lamination typical big lamination |
| Conductor |  $          8  |  $      1,879  |  | per pound typical price |
| Insulation |  $       175  |  $      7,547  |  | per inch scaling from FMI Lambertson |
| Core parts |  $  20,000  |  $     20,000  |  | WAG |
| Manifold & bus work |  $  27,000  |  $     27,000  |  | per magnet scaling from FMI Lambertson |
| Inner beam tube |  $    50.00  |  $      1,055  |  | per meter plus flanges, etc |
| Parts total |  |  $     69,618  |  |  |

- Cost estimates: Large-aperture PD Quadrupoles:1.2 m, 17.5 cm aperture, Tech Div. Fermilab

- 10k*

- 13k*

- 45.6k*

- _*Labor is at least a factor of 2 high at Fermi vs. industry_

-                              Labor total    (1773 hrs, est)  $  ~ 27k                             reduced labor rate by 2 from TDiv rate
- TOTAL, MAX                                                     $     73K
**Scale to 13 cm aperture                                  $     54k                             NOTE: average magnet length is 1.1 m  **

- M&S

## 15 Hz, resonant main power source

- Cost estimate is for dipole and quadrupole main power supply network.

| Item | Quantity | Unit Cost
[k$] | Total Cost
[k$] |
| --- | --- | --- | --- |
| Resonant cell choke, Lch | 22 | 478 | 10,516 |
| Resonant cell choke, L1 | 22 | 107 | 2,354 |
| Resonant cell capacitor, C | 22 | 199 | 4,378 |
| Resonant cell capacitor, C1 | 22 | 160 | 3,520 |
| Power supply | 4 | 500 | 2,000 |
| DC bus, bus supports, magnet terminations, etc | lot | 1,500 | 1,500 |
| Control and regulation system | lot | 1,200 | 1,200 |
| Installation  | 10,000 m-hrs | 0.05 | 500 |
| Total |  |  | 25,968 |

- Labor will be ~25k, giving $50k for a 15 Hz resonant main power supply

## Revised estimate for 2.5-5 GeV FFAG ring:      magnets + power supply

- Magnet cost:
- 300 magnets x $54k = $16 Million
- 15 Hz resonant power supply:
- Single main supply: ~$100K