# DRAFT Version, under construction.

This is the version of the Silicon Detector modelled as of November, 2006, post Valencia.

The compact description of this detector in xml format can be found at http://www.lcsim.org/detectors/sid01.zip . What follows is a plain text description of the file compact.xml found in this zip file.

Where a material is listed as xx% coverage, the density of the material has been reduced to xx% of its nominal value to mimic the effect of cutouts in the material.

The tracking region is defined to be a cylinder with radius 126.5cm and z extent +/- 167.9cm.

### Beampipe:

The beampipe consists of a cylindrical central tube and forward/backward conical sections. The 0.040cm thick Beryllium central tube has an inner radius of 1.2cm and extends to |z|<6.25cm. The conical sections have a cone half-angle of 43.4mrad with an inner radius that flares from 1.2 cm at 6.25cm to 8.218cm at |z|=167.9cm. The conical sections are 0.0875Cm thick Be for 6.25cm<|z|<37.5cm, where they transition to steel. The thickness of the steel section flares from 0.0875cm at |z|=37.5cm to 0.1992cm at |z|=167.9cm. A titanium liner on the inner surface of the beam pipe consists of a 0.0025cm thick cylinder and 0.0075cm thick conical sections.

### Vertex Detector:

The vertex detector is composed of a central barrel system with five layers and forward systems composed of four disks.

#### Barrels

The barrels are composed of .0113cm thick Silicon, of which the outer .002cm is sensitive, with the following inner radii and |z| extants:

Layer |
Inner Radius |
|z| Extant |
---|---|---|

1 |
1.46cm |
6.25cm |

2 |
2.26cm |
6.25cm |

3 |
3.54cm |
6.25cm |

4 |
4.80cm |
6.25cm |

5 |
6.04cm |
6.25cm |

Sensors are supported by cylinders made of 0.026cm thick carbon fiber with 25% coverage.

Layer |
Inner Radius |
|z| Extant |
---|---|---|

1 |
1.43cm |
6.27cm |

2 |
2.23cm |
6.27cm |

3 |
3.51cm |
6.27cm |

4 |
4.77cm |
6.27cm |

5 |
6.01cm |
6.27cm |

The cylinders attach to 0.026cm thick carbon fiber (25% coverage) bulkheads that span 1.44cm<r<7.16cm and have an inner |z| of 6.27cm. The vertex detector is attached to the support tube by 0.026cm thick carbon fiber (25% coverage) support disks that span 1.44cm<r<16.87cm and have an inner |z| of 6.30cm.

#### Disks

There are four forward disks on either end, composed of a total of .0113cm of silicon, of which the inner .002cm is sensitive. The radial extant and inner |z| for the disks are:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

1 |
1.4cm |
7.1cm |
7.18cm |

2 |
1.6cm |
7.1cm |
9.02cm |

3 |
1.8cm |
7.1cm |
12.16cm |

4 |
2.0cm |
7.1cm |
17.00cm |

The forward disk supports are 0.026cm thick carbon fiber (25% coverage) disks located as follows:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

1 |
1.395cm |
16.87cm |
7.21cm |

2 |
1.595cm |
16.87cm |
9.05cm |

3 |
1.795cm |
16.87cm |
12.19cm |

4 |
1.995cm |
16.87cm |
17.03cm |

#### Readout Electronics and Cables

For the barrel, readout electronics are modeled as G10 rings that are currently located outside the support membrances:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
Thickness |
---|---|---|---|---|

1 |
1.46cm |
1.66cm |
6.4cm |
0.5cm |

2 |
2.26cm |
2.46cm |
6.4cm |
0.5cm |

3 |
3.54cm |
3.74cm |
6.4cm |
0.5cm |

4 |
4.80cm |
5.00cm |
6.4cm |
0.5cm |

5 |
6.04cm |
6.24cm |
6.4cm |
0.5cm |

Forward disk readout electronics are modeled as inner and outer rings, both made of G10:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
Thickness |
---|---|---|---|---|

1-in |
1.3cm |
1.4cm |
6.98cm |
0.2cm |

2-in |
1.5cm |
1.6cm |
8.82cm |
0.2cm |

3-in |
1.7cm |
1.8cm |
11.96cm |
0.2cm |

4-in |
1.9cm |
2.0cm |
16.80cm |
0.2cm |

1-out |
7.1cm |
7.6cm |
6.98cm |
0.2cm |

2-out |
7.1cm |
7.6cm |
8.82cm |
0.2cm |

3-out |
7.1cm |
7.6cm |
11.96cm |
0.2cm |

4-out |
7.1cm |
7.6cm |
16.80cm |
0.2cm |

Barrel cables first are brought radially down to the beam pipe. These radial cables are modeled as Cu disks:

Inner Radius |
Outer Radius |
Inner |z| |
Thickness |
---|---|---|---|

1.32cm |
2.26cm |
6.90cm |
0.0057cm |

2.26cm |
3.54cm |
6.90cm |
0.0031cm |

3.54cm |
4.80cm |
6.90cm |
0.0016cm |

4.80cm |
6.04cm |
6.90cm |
0.0007cm |

The remaining cable and service materials are located along the beam pipe. Inner cables are 0.012cm thick copper and run conically from an inner radius of 1.32cm at |z|=6.9cm to a radius of 1.455cm at |z|=10.0cm. Service material is 0.3cm thick G10 that runs conically from an inner radius of 1.455cm at |z|=10cm to 1.542cm at |z|=12cm. Outer cables are modeled as copper that flares from a thickness of 0.010cm with an inner radius of 1.542cm at |z|=12cm to a thickness of 0.004cm with an inner radius of 8.310cm at |z|=167.9cm.

#### Support Tube

The entire vertex detector is enclosed within a double walled carbon fiber support tube. The support tube walls are 0.05cm thick carbon fiber with inner radii of 16.87cm and 18.42cm and a |z| extant of |z|<89.48cm. The ends of the support tube double-walled disks of 0.05cm thick carbon fiber disks located as follows:

Wall |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

Inner |
4.80cm |
16.87cm |
86.88cm |

Outer |
4.91cm |
16.87cm |
89.43cm |

### Tracker:

The tracker is composed of five cylindrical barrels with four disk-shaped endplanes. The z extent of the barrels increases with radius and the endplane for each extends beyond its cylinder in radius to provide overlap. The sensitive medium is silicon, assembled into carbon-fiber/Rohacell/PEEK modules and read out via a bump-bonded chip and Kapton/Copper cables. These modules are supported by carbon-fiber/Rohacell/carbon-fiber barrels or disks. Each barrel cylinder is supported from the next barrel out by an annular carbon fiber-ring. Outside each of these support rings in z, G10/Copper printed circuit boards are mounted for power and readout distribution to all silicon modules in a layer.

#### Barrels:

The radii and |z| extents of the barrel silicon layers are:

Layer |
Inner Radius |
|z| Extent |
---|---|---|

1 |
21.8cm |
55.8cm |

2 |
46.8cm |
82.5cm |

3 |
71.8cm |
108.3cm |

4 |
96.8cm |
134.7cm |

5 |
121.8cm |
160.6cm |

The estimated material thickness for modules, silicon, readout, and cables are averaged over the barrel and are given by:

Material |
Layer 1 |
Layer 2 |
Layer 3 |
Layer 4 |
Layer 5 |
---|---|---|---|---|---|

PEEK |
0.02cm |
0.02cm |
0.02cm |
0.02cm |
0.02cm |

Rohacell31 (50% coverage) |
0.3cm |
0.3cm |
0.3cm |
0.3cm |
0.3cm |

Epoxy |
0.0175cm |
0.0175cm |
0.0175cm |
0.0175cm |
0.0175cm |

Carbon Fiber |
0.016cm |
0.016cm |
0.016cm |
0.016cm |
0.016cm |

Silicon (active) |
0.03cm |
0.03cm |
0.03cm |
0.03cm |
0.03cm |

Silicon (dead) |
0.00048cm |
0.00048cm |
0.00048cm |
0.00048cm |
0.00048cm |

Kapton |
0.0038cm |
0.0051cm |
0.0064cm |
0.0078cm |
0.0091cm |

Copper |
0.00038cm |
0.00052cm |
0.00065cm |
0.00079cm |
0.00093cm |

The barrel support cylinders are composed of .05cm CarbonFiber, 0.80cm of Rohacell31 (15% coverage) and 0.05cm CarbonFiber. The inner radii and |z| extent are given by:

Layer |
Inner Radius |
|z| Extent |
---|---|---|

1 |
20.6cm |
57.7cm |

2 |
45.6cm |
84.3cm |

3 |
70.6cm |
110.2cm |

4 |
95.6cm |
136.6cm |

5 |
120.6cm |
162.4cm |

The barrels are supported by 0.05cm thick carbon fiber (15% coverage) rings:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

1 |
21.5cm |
45.6cm |
57.0cm |

2 |
46.5cm |
70.6cm |
83.6cm |

3 |
71.5cm |
95.6cm |
109.5cm |

4 |
96.5cm |
120.6cm |
135.9cm |

5 |
121.5cm |
126.5cm |
161.7cm |

#### Endcap:

Each layer is composed of double-sided sensor modules to measure coordinates in two views. The table below shows the radial extant of the disks and the inner |z| position for the "A" and "B" sensor planes.

Layer |
Inner Radius |
Outer Radius |
|z| for A Plane |
|z| for B Plane |
---|---|---|---|---|

1 |
20.7cm |
49.4cm |
85.5cm |
85.9cm |

2 |
20.7cm |
74.7cm |
111.4cm |
111.8cm |

3 |
20.7cm |
99.9cm |
137.8cm |
138.2cm |

4 |
20.7cm |
125.0cm |
163.6cm |
164.0cm |

Each A plane has the following material thicknesses:

Material |
Layer 1 |
Layer 2 |
Layer 3 |
Layer 4 |
---|---|---|---|---|

Silicon (active) |
0.03cm |
0.03cm |
0.03cm |
0.03cm |

Silicon (dead) |
0.00048cm |
0.00048cm |
0.00048cm |
0.00048cm |

Kapton |
0.0051cm |
0.0064cm |
0.0078cm |
0.0091cm |

Copper |
0.00052cm |
0.00065cm |
0.00079cm |
0.00093cm |

PEEK |
0.02cm |
0.02cm |
0.02cm |
0.02cm |

Rohacell31 (50% coverage) |
0.3cm |
0.3cm |
0.3cm |
0.3cm |

Epoxy |
0.0175cm |
0.0175cm |
0.0175cm |
0.0175cm |

Carbon Fiber |
0.016cm |
0.016cm |
0.016cm |
0.016cm |

Each B plane has the following material thicknesses:

Material |
Layer 1 |
Layer 2 |
Layer 3 |
Layer 4 |
---|---|---|---|---|

Silicon (active) |
0.03cm |
0.03cm |
0.03cm |
0.03cm |

Silicon (dead) |
0.00048cm |
0.00048cm |
0.00048cm |
0.00048cm |

Kapton |
0.0051cm |
0.0064cm |
0.0078cm |
0.0091cm |

Copper |
0.00052cm |
0.00065cm |
0.00079cm |
0.00093cm |

The endcap supports are disks made of two 0.05cm thick Carbon Fiber planes separated by a 0.63cm thick layer of Rohacell31 (15% coverage). The radial span and inner z coordinate are:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

1 |
20.5cm |
51.0cm |
84.5cm |

2 |
20.5cm |
76.3cm |
110.3cm |

3 |
20.5cm |
101.3cm |
136.7cm |

4 |
20.5cm |
126.3cm |
162.6cm |

#### Services

The readout and power distribution boards are mounted on the outside surfaces of the barrel support rings. The regions occupied by these boards and the average thickness of the material they represent are given by:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
G10 Thickness |
Copper Thickness |
---|---|---|---|---|---|

1 |
25.7cm |
45.6cm |
57.1cm |
0.057cm |
0.0038cm |

2 |
51.0cm |
70.6cm |
83.7cm |
0.102cm |
0.0068cm |

3 |
76.3cm |
95.6cm |
109.6cm |
0.108cm |
0.0072cm |

4 |
101.3cm |
120.6cm |
136.0cm |
0.186cm |
0.0124cm |

5 |
101.3cm |
120.6cm |
167.0cm |
0.246cm |
0.0164cm |

Note that in layer five, due to the constraints of the calorimeter, the readout boards are not mounted on this annular ring, but rather at smaller radius.

#### Forward Disks

There are also three forward disks composed of double-sided sensor modules to measure coordinates in two views. The table below shows the radial extant of the disks and the inner |z| position for the "A" and "B" sensor planes.

Layer |
Inner Radius |
Outer Radius |
|z| for A Plane |
|z| for B Plane |
---|---|---|---|---|

1 |
2.78cm |
16.67cm |
20.40 |
20.80cm |

2 |
7.51cm |
16.67cm |
53.85cm |
54.25cm |

3 |
11.65cm |
16.67cm |
82.95cm |
83.35cm |

Each A Plane has the following material thicknesses:

Material |
Layer 1 |
Layer 2 |
Layer 3 |
---|---|---|---|

Silicon (active) |
0.03cm |
0.03cm |
0.03cm |

Silicon (dead) |
0.00048cm |
0.00048cm |
0.00048cm |

Kapton |
0.0038cm |
0.0038cm |
0.0038cm |

Copper |
0.00038cm |
0.00038cm |
0.00038cm |

PEEK |
0.02cm |
0.02cm |
0.02cm |

Rohacell31 (50% coverage) |
0.3cm |
0.3cm |
0.3cm |

Epoxy |
0.0175cm |
0.0175cm |
0.0175cm |

Carbon Fiber |
0.016cm |
0.016cm |
0.016cm |

Each B Plane has the following material thicknesses:

Material |
Layer 1 |
Layer 2 |
Layer 3 |
---|---|---|---|

Silicon (active) |
0.03cm |
0.03cm |
0.03cm |

Silicon (dead) |
0.00048cm |
0.00048cm |
0.00048cm |

Kapton |
0.0038cm |
0.0038cm |
0.0038cm |

Copper |
0.00038cm |
0.00038cm |
0.00038cm |

The forward disk supports are disks made of two 0.05cm thick Carbon Fiber planes separated by a 0.35cm thick layer of Rohacell31 (15% coverage). The radial span and inner z coordinate are:

Layer |
Inner Radius |
Outer Radius |
Inner |z| |
---|---|---|---|

1 |
2.68cm |
16.87cm |
21.18cm |

2 |
7.41cm |
16.87cm |
54.37cm |

3 |
11.55cm |
16.87cm |
83.48cm |

### Calorimeters:

#### Electromagnetic Calorimeter:

This element sets the basic size and aspect ratio for the rest of the detector. The inner radius for the barrel is 127cm. The aspect ratio is set to cos(theta)=0.8, meaning the inner z of the endcap EM calorimeter is at z of 168cm.

The EM calorimeter is a sampling calorimeter composed of 20 layers of

material |
thickness |
---|---|

Tungsten |
.250cm |

G10 |
.068cm |

Silicon |
.032cm |

Air |
.025cm |

followed by ten layers of

material |
thickness |
---|---|

Tungsten |
.50cm |

G10 |
.068cm |

Silicon |
.032cm |

Air |
.025cm |

The endcap plug sits inside the barrel cylinder, so the barrel z extent is +/- 182.0cm.

The endcap starts at an inner radius of 26cm and extends out to 126.5cm.

##### Segmentation

The readout is 3.5mm square cells.

#### Hadron calorimeter:

The hadron calorimeter is a sampling calorimeter composed of 34 layers of

material |
thickness |
---|---|

Steel |
2.0cm |

G10 |
0.3cm |

PyrexGlass |
0.11cm |

RPCGas |
0.12cm |

PyrexGlass |
0.11cm |

Air |
0.16cm |

It begins immediately outside of the EM calorimeters, with the endcap plug sitting inside the barrel.

The barrel inner radius is 141.0 with a z extent of +/- 277.2cm.

The endcap extends from an inner radius of 26.0 cm to an outer radius of 140.75, inner z of 182.0.

##### Segmentation

The readout is 1cm squares.

### Solenoid:

The solenoid is modelled as a cylinder with an inner radius of 250cm. This is larger than the outer radius of the hadron calorimeter since we will not be building a cylindrical detector, but a polygonal one (current thinking is octagonal). The barrel composition is as follows:

material |
thickness |
z |
---|---|---|

Steel |
6.0cm |
271.0cm |

Air |
8.5cm |
271.0cm |

Aluminum |
39.3cm |
262.5cm |

Steel |
6.0cm |
262.5cm |

Air |
20.0cm |
271.0cm |

Steel |
3.0cm |
271.0cm |

This is capped with disk endplates of 6cm steel from r=250cm to 332.8cm

### Muon System:

The muon system is implemented as a sampling calorimeter composed of 48 layers of:

material |
thickness |
---|---|

Iron |
5.0cm |

G10 |
0.3cm |

PyrexGlass |
0.11cm |

RPCGas |
0.12cm |

PyrexGlass |
0.11cm |

Air |
0.86cm |

The barrel inner radius is 333.0cm with z extent of +/- 277cm.

The endcap sits outside the barrel at an inner z of 277.5cm and radius from 26.0cm to 645.0cm

The field is solenoidal, constant 5 Tesla along z up to half the coil thickness and -0.6 outside.

##### Segmentation

The readout is 3cm squares.

### Masks and Far Forward Detectors

This detector is designed for the 2mr beam crossing solution. The far forward plug extends out to

a radius of 25cm. It starts with an electromagnetic calorimeter with the same composition as the

endcap calorimeter, extending from 8.68cm out to 25cm.

The calorimeter is backed up by a conically tapered tungsten mask, inner radius 8.68 at z of 182cm,

tapering to 16cm at z of 330cm. The outer radius is constant at 25cm.

There is a far forward low-Z shield (10cm thick Beryllium) at z of 285cm, with a 1.5 cm central aperture.

This is followed by a 50 layer silicon-tungsten calorimeter at z of 295cm, with a single aperture for

both the incoming and outgoing beams, radius 2cm.

##### Segmentation

All the far forward electromagnetic calorimeters have 3.5mm square readout.