The tracker has 32 layers instrumented with silicon
The TkrLayer class provides access to a single layer of Si Strips. It contains a list of strips that were above threshold, and TOT and ERRF values.
| TkrLayer | ||
| Members | Range | Comment |
| getErrf() | 0 or 1 | Returns status of controller chip 0 = OK, 1 = bad |
| getLayer() | 0 to 15 | Layer ID. There are 16 xy planes instrumented with silicon (corresponds to 17 mechanical trays). |
| getStrips() | Returns the ROOT structure pointer to a container where hit strips are located. One needs to use getID() for a strip in order to find out which strip number has a hit above the threshold. (see below) | |
| getTOT() | 0 or 1 | Returns the time over threshold in counts steps of 4 clock cycles. 1 clock cycle = 50 ns, each count is 200 ns. The arguments are 0 for the A controller , 1 is for the B controller. Cable 0 and 6 used A controllers and cable 3 and 5 are B controllers. The remaining cables were not read out. |
| getXY() | 0 or 1 | Returns coordinate measured Y=0 or X=1 (an X layer means a layer that measures X ) |
For experts only: In the coding of the ROOT files X means orientation of strips and not the measured coordinate. A typical user does not need to worry about it and should go with the definition given in the table above.
| StripID | ||
| Members | Range | Comment |
| getID() | 0 to 1599 | The largest strip number in a given layer is determined
by the total number of ladders in the layer; 0 if 0 ladders 959 if 3 ladders 1279 if 4 ladders 1599 if 5 ladders |
| Lead Converters are place right ABOVE the following layers (x or y means measured coordinate and NOT strips orientation) | ||
| NO LEAD | Thin Pb (3.5%) | Thick Pb (25%) |
| 0x,1y | 5y,6x,7y,8x,9y,10x,11y,12x,13y,14x,15y | 2x,3y,4x |