Nominal (ie. layout db) Current (at 7 TeV) 5520 A

Nominal Field (at 7 TeV) 3.5 T

Nominal Current (at 7 TeV) 5520 A

Nominal Field (at 7 TeV) 3.5 T

**Constants**

sepARC = 0.194;

sepIR4 = 0.420;

Dsep4 = 71.901;

lengthMBRB = 9.45 m

lengthMBRS = 9.45 m

**Required Angle**

AIP4 = ArcTan[(sepIR4 - sepARC)/2/Dsep4]

R0 = 0.0; (not used - below for completeness)

ad3L4 = AIP4*(1 - R0);

ad3R4 = AIP4*(1 - R0);

ad4L4 = AIP4*(1 - R0);

ad4R4 = AIP4*(1 - R0);

**Normalized strength**

kd3L4 = ad3L4/lengthMBRS = 0.000166307

kd3R4 = ad3R4/lengthMBRS = 0.000166307

kd4L4 = ad4L4/lengthMBRB = 0.000166307

kd4R4 = ad4R4/lengthMBRB = 0.000166307

**Required Field**

B = kd3L4*7000/.2998 = 3.88309 T

Bdl = B x 9.45 = 36.6952 Tm

**Required Current**

Transfer Function D3 - MBRS = 0.005991848 Tm/A (from layout database values quoted above)

Transfer Function D4 - MBRB = 0.0059918 Tm/A

current D3 at 7 TeV = Bdl/0.005991848 = **6124.19 A **

current D4 at 7 TeV = **6124.24** **A **

However, if we look at the measured D3 TF provided by Sandor see plot

From a quick look at the plot TF at around 6000A is 0.665 T/kA or 6.251 T.m/kA. This gives us around **5870 A for D3.**

From actual measured data D3 TF is around 0.000662406 T/A at 5900 A. This gives us around **5862 A for D3. **In agreement.

From actual measured data D4 TF is around 0.000632282 T/Aat 6000 A. This gives us around **6141 A for D4.**

ML April 08