Rod phi positions and numbering


Rods are identified by the layer number (TOB1 to TOB6), the letter P or M indicating the positive or negative z side, and a number going from 1 to the total number of rods in the layer. Therefore, for example, the rod n 23 of the second layer covering the positive z region is identified by the label TOB2P23.

In each layer rods are a two different radii. Rod # 1 is defined to be the first rod on the inner radius with the centre of gravity at positive phi, and then rods are numbered with increasing phi. Thus, the odd numbered rods are always on the inner radius and the even numbered on the outer radius of the layer.

The phi position of all rods is given by the table below.

Table 1: Phi positions of TOB rods. The position given refers to the centre of gravity. In the first column the position of rod #1 is given. In the second column the increment in angle between consecutive rods. In the third column the position of the last rod. In each cell, values are given in radians in the first row and in degrees in the second row (in red and bold).
Layer #n of rodsphi of rod #1incrementphi of last rod
TOB1N=42phi(1)=(1/16 - 1/21)* 2pi
5.3571
1/42 * 2pi
8.5714
phi(N) = phi(1) + 41/42 * 2pi
356.7857
TOB2N=48phi(1)=(1/16 + 6/7 - 11/12 )* 2pi + .0190
2.1601
1/48 * 2pi
7.5000
phi(N) = phi(1) + 47/48 * 2pi
354.6601
TOB3N=54phi(1)=(1/16 + 6/7 - 8/9 )* 2pi + .0342
13.0309
1/54 * 2pi
6.6667
phi(N) = phi(1) - 1/54 * 2pi
6.3643
TOB4N=60phi(1)=(1/16 + 6/7 - 14/15)* 2pi + .1136
1.5802
1/60 * 2pi
6.0000
phi(N) = phi(1) + 59/60 * 2pi
355.5802
TOB5N=66phi(1)=(1/16 + 6/7 - 10/11)* 2pi + .0810
8.4397
1/66 * 2pi
5.4545
phi(N) = phi(1) - 1/66 * 2pi
2.9851
TOB6N=74phi(1)=(1/16 + 6/7 - 34/37)* 2pi + .0195
1.3779
1/74 * 2pi
4.8649
phi(N) = phi(1) + 73/74 * 2pi
356.5130


D.A.