Table A1.

The ESE parameter set, with the Hybrid1 parameterization of $h(t)$ and the Exponential parameterization of $b_{\text{c}2}(\epsilon )$ for data not corrected for magnetic self field.

			Core scaling parameters
Nb3Sn conductor	$C$ (AT)	${B_{\text{c}2}}^{\ast }(0,0)$ (T)	${T_{\text{c}}}^{\ast }(0)$ (K)	$\eta$	$s$	${\epsilon }_{l0}$a (%)	$C_1$ b	$p$ c	$q$ c	RMSFDd (%)	RMSEd (%)
OST-RRP®	50 510	29.09	16.94	2.25	1.15	−0.355	0.75	0.50	2.06	9.0	0.120
WST-ITER	21 020	31.02	16.81	2.02	1.39	−0.302	0.82	0.57	1.83	4.8	0.114
LUVATA	14 960	29.70	16.43	1.97	1.40	−0.321	0.66	0.56	1.70	2.0	0.078
VAC	7 630	29.91	16.84	2.00	1.10	−0.313	0.92	0.48	1.44	4.6	0.247
EM-LMI	11 920	30.79	17.02	2.38	0.87	−0.271	1.14	0.50	1.84	3.6	0.170

Notes:

^aThe compressive prestrain values ${\epsilon }_{l0}(=-{\epsilon }_m)$ are dependent on the strain introduced by the sample holder on cooldown, and therefore are not strictly part of the core parameter set. All these samples were soldered with Pb–Sn solder to Cu–Be sample holders.

^bThe $C_1$ values for the Exponential $b_{\text{c}2}(\epsilon )$ model in the last core-parameter column of table A1 give a strain sensitivity index for comparing the different conductors (because the strain parameter $C_1$ is a not interdependent on other strain parameters). A comparison of the $C_1$ values in this column shows immediately that the EM-LMI conductor has the greatest strain sensitivity ($C_1=1.14$), followed by VAC, WST-ITER, and OST-RRP^® conductors. This is not the case for the Invariant Strain Function parameters in table A2, or for any of the other $b_{\text{c}2}(\epsilon )$ models (except the Extended Power Law model), because these other models have multiple parameters that compensate each other and thus require the $b_{\text{c}2}(\epsilon )$ function to be plotted before a conductor’s relative strain sensitivity is known.

Due to the very low value of ${\epsilon }_{0,\text{irr}}$ for the OST-RRP^® conductor (Cheggour et al 2010), there were not enough data on the tensile side of the strain peak to determine the value of ${\epsilon }_{l0}(=-{\epsilon }_{\text{m}})$ independently of $C_1$. Thus, for this particular situation, $C_1$ is not truly an independent strain sensitivity index, since the scarcity of tensile data gives it freedom to interact with ${\epsilon }_{l0}$ to some degree to improve the fit. For example, note the difference between the ${\epsilon }_{l0}$ and $-{\epsilon }_{\text{m}}$ values for this conductor in tables A1 and A2, whereas the correspondence in the values of these two parameters was close for all the other conductors. Although the value of $C_1$ may not be as precise an index of strain sensitivity for this particular conductor, a detailed inspection of the data showed that the $C_1$ ranking shown in the tables A1 was nevertheless correct.

^cPinning-force shape parameters $p$ and $q$ were determined as part of the simultaneous global-fitting process for all the datasets, except the high-$J_{\text{c}}$ OST-RRP^® dataset. It lacked sufficient low-magnetic field data to determine $p$, so $p$ was fixed at $p=0.5$ for this particular conductor. (The parameter $q$ was determined from the master scaling curve, but it would also have worked well to fix $p=0.5$ and fit $q$ as part of the simultaneous fitting process.)

^dThe RMSFD and RMS $F_{\text{P}}$ errors in the last two columns are defined by equations (3a) and (3b) in the text. Errors are expressed as percentages to facilitate comparisons between conductors. The percentage RMSE $F_{\text{P}}$ errors in these tables correspond to effective RMS $I_{\text{c}}$ errors of 1–5 A at 12 T, depending on the $J_{\text{c}}$ of the conductor (section 3).