From available MQTL cold data to FIDEL reference tables

W. Venturini Delsolaro

FIDEL meeting 22/2/2007

Available and missing cold data• All Q6 measured with Single Stretch Wire (integral TF of 6 MQTL in series)• Single MQTL assemblies in SM18

– SSS520, SSS532 (SSW)– SSS521, SSS525 with horizontal shaft; in total 8 modules that should be used for the w/c

correlation of the TF

• 13 MQTL modules and 2 twin apertures measured at cold in the vertical cryostats: shaft is slightly shorter than magnetic length, relative values match SM18 data after scaling

• Geometric, Saturation and Magnetization contributions should come from the above, for TF and harmonics

• Magnetization at low current, minor hysteresis loops: some data exist. More experimental and modeling work is necessary

We expect no decay (was partially checked), but ramp effects needs to be measured, by the way…

on current ramps, remember to take into account the parallel resistors, giving a

(also true for other correctors)

dt

dI

RdtdI

L

par

6.0 :current leakage

280

290

300

310

320

330

340

0 100 200 300 400 500 600

Current (A)

TF

(T

/kA

)

B4 central field * 1.3 m (theoretical magneticlength)SSW (true integral)

reconstructed curve

B4 central field*1.3 m

mqtl41 a1 sm18 shaft

mqtl41 a1 sm18 shaft

MQTL-41-A1-SSW

MQTL-41-a2-SSW

SSS 521 (ssw)

correction required ~3% between B4 central field*theor. Lm and SSW

StrategyTF: Warm data available for all magnets.

Infer the geometric component from w/c correlation based on SSW data.

Use generic values for the magnetization and the saturation components, computed from Block 4 data

Same for the “ramp” component, data still to be collected

Harmonics: w/c correlations can be based on the whole set of data (Block 4 + SM18)