# Presentation: 751031

## Phase 1 Upgrade Proposals:Inner Triplet DipolesP. Wanderer LARP CM10April 24, 2008

***bnl - fnal- lbnl - slac***

_**US LHC Accelerator Research Program**_

## Requirements

- Davide Tommasini

**Requirements**

| Magnet gap | 120 mm |
| --- | --- |
| B•L @ injection | 1.7 T•m per interaction side |
| B•L @ top energy | 27 T•m per interaction side  |
| Good Field Region | radius 50 mm |
| dB/B in GFR at injection | ± 5•10-4 |
| dB/B in GFR at top energy | ± 2•10-4 |

- LARP CM10 DX Wanderer

- April 24, 2008

## D1 dipoles at IR 1, 5

- LIUWG (LHC IR Upgrade Working Group) report on D1: replacing present D1 dipoles with superconducting dipoles would have three advantages:
- Dipole aperture could match quad aperture (~ 110-120 mm)
- Longer slot length available for correctors
- Lower cost than replacement resistive dipoles.
- RHIC DX dipoles:
- sufficient aperture (180 mm)
- field (3.6 T, Lm = 3.7 m) with two DX = 27 Tm, D1
- yoke o.d. = 622 mm [CERN D1 has 570 mm o.d.]
- L = 49 mH, 6.8 kA and
- 6.8 kA  4.4 T, 1100 kJ stored energy

- LARP CM10 DX Wanderer

- April 24, 2008

## DX Cold mass cross section

- LARP CM10 DX Wanderer

- April 24, 2008

## DX Initial Quench Performance

- LARP CM10 DX Wanderer

- April 24, 2008

## DX Quench Performance in RHIC

- There are 12 DX magnets in RHIC
- RHIC runs 6 – 9 months/year, depending on $.
- RHIC has just completed Run 8 + 1 commissioning year = 9 years.
- 	7 cooldowns from room temperature (2 periods at 77 K)
- After a thermal cycle, there are typically 12 quenches (i.e., 1/magnet) to reach operating field (4.4 T).  For an operating field of 4T, no quenches are expected  plan to run at 3.6T in LHC.
- DX prototype data  RHIC quenches originate in the ends of the coils, due to the large tilt of the cable.  We would redesign the D1 ends to reduce the tilt (i.e., increase mech. stability)

- LARP CM10 DX Wanderer

- April 24, 2008

## DX transfer function

- LARP CM10 DX Wanderer

- April 24, 2008

## DX allowed harmonics (r = 60 mm)

- LARP CM10 DX Wanderer

- April 24, 2008

| Harmonicat 60 mm | Mean |  | Standard Deviation |  |
| --- | --- | --- | --- | --- |
|  | 30 A(13 magnets) | 6600 A(6 magnets) | 30 A(13 magnets) | 6600 A(6 magnets) |
| b1 | 0.04 | 0.03 | 0.63 | 0.72 |
| b2 | 0.53 | -0.09 | 2.09 | 1.90 |
| b3 | 0.00 | -0.03 | 0.19 | 0.22 |
| b4 | -2.68 | -2.95 | 0.57 | 0.41 |
| b5 | 0.03 | -0.05 | 0.10 | 0.15 |
| b6 | -1.91 | -1.76 | 0.17 | 0.12 |
| b7 | 0.01 | 0.01 | 0.04 | 0.06 |
| b8 | -1.09 | -1.15 | 0.07 | 0.07 |
| b9 | 0.00 | 0.01 | 0.02 | 0.02 |
| b10 | -1.13 | -1.15 | 0.02 | 0.02 |
| a1 | -1.00 | -2.33 | 2.37 | 0.96 |
| a2 | -2.54 | -2.70 | 0.53 | 0.32 |
| a3 | 0.38 | -0.06 | 0.99 | 1.10 |
| a4 | 0.30 | 0.34 | 0.25 | 0.16 |
| a5 | 0.34 | 0.19 | 0.37 | 0.38 |
| a6 | -0.21 | -0.15 | 0.15 | 0.08 |
| a7 | 0.19 | 0.15 | 0.11 | 0.11 |
| a8 | -0.04 | -0.05 | 0.04 | 0.04 |
| a9 | 0.09 | 0.08 | 0.04 | 0.05 |
| a10 | 0.03 | 0.06 | 0.02 | 0.02 |

- LARP CM10 DX Wanderer

- April 24, 2008

## Field Quality

- Must scale DX (r=60mm) to D1 (r=50mm)
- Injection:  ~ 110A – not well measured in DX; large magnetization harmonics (sextupole, decapole)
- Top field:  ~ 5.5 kA – yoke saturation
- 	sextupole: ok
- 	decapole:  DX 2.9 units, D1 2 units
- Other harmonics – none larger than 3 units (r=60mm)

- LARP CM10 DX Wanderer

- April 24, 2008

## Cost and Schedule

- Mike Anerella has prepared preliminary versions of the schedule and cost.
- The funding profile is sharply peaked in FY10.  We have not had time to look into the effect of smoothing the funding profile on the schedule.
- We will also look into the schedule gain if small amounts of funding can be available in the latter half of FY09.  Example:  test cable run.

- LARP CM10 DX Wanderer

- April 24, 2008