Global ID (gid)

Info

This page only illustrates the gid of each detector element. To convert gid to other information, please refer to Geometry.

To better locate each detector element, a global ID (gid) is defined. GID always starts from 0 and increases along the detector elements. The increasing order is described by a tuple-like structure.

For example, MDC gid can be described as (layer, wire), which means it increases first along the wire and then along the layer, as shown below:

layer	wire	gid
0	0	0
0	1	1
0	...	...
1	0	40
1	1	41
...	...	...

There are 40 wires on layer-0 in MDC.

MDC

Range	Increasing Order
0~6795	(layer, wire)

Same as BOSS

MDC gid is same as those given by MdcGeomSvc in BOSS

TOF

Range	Increasing Order	Part
0~95	(strip, end)	Scint Endcap 0
96~447	(layer, phi, end)	Scint Barrel
448~543	(phi, end)	Scint Endcap 1
544~1407	(module, strip, end)	MRPC Endcap 0
1408~2271	(module, strip, end)	MRPC Endcap 1

EMC

Range	Increasing Order	Part
0~479	(theta, phi)	Endcap 0
480~5759	(theta, phi)	Barrel
5760~6239	(-theta, phi)	Endcap 1

The concrete relationship between gid and (theta, phi) for EMC endcap 0 is:

Range	Number of Crystals	Theta	Description
0~63	64	0	Innermost layer
64~127	64	1
128~207	80	2
208~287	80	3
288~383	96	4
384~479	96	5	Outermost layer

The concrete relationship between gid and (theta, phi) for EMC endcap 1 is:

Range	Number of Crystals	Theta	Description
5760~5855	96	5	Outermost layer
5856~5951	96	4
5952~6031	80	3
6032~6111	80	2
6112~6175	64	1
6176~6239	64	0	Innermost layer

Same as BOSS

EMC gid is same as those given by EmcCalibSvc in BOSS

MUC

Under development

CGEM

Under development