# Presentation: 323114

## Tracking Detectors for 

**the LHC Upgrade**
**    ****Materials (RD50)**
**    ****Trapping in Silicon (Liverpool)**
**    ****Signal/Threshold (need input)**
**Hartmut F.-W. Sadrozinski**
***SCIPP, UC Santa Cruz***

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

## Integrated Luminosity
(radiation damage) dictates the 
		detector technology

Instantaneous rate 
(particle flux) dictates the 
		detector geometry

**Integrated Luminosity**
**(radiation damage) dictates the **
**	****	****detector ****technology**
**Instantaneous rate**** **
**(particle flux) dictates the **
**	****	****detector ****geometry**

**sATLAS Tracker Regions**

- Inner
- Pixel

**	**
**Middle:****	****20 cm ≤ r ≤ 55 cm **
**	****	****short strips**
**	****Threshold = 4400 e****-**** ( 0.7 fC)**

**Outer:****	****55 cm ≤ r ≤ 1 m****	**
**	****	****“****long strips”**
**	**** ****Threshold = 6250 e****-**** ( 1.0 fC)**

**Straw-man layout**:
**Inner:****	****6 cm ≤ r ≤ 12 cm****	**
**	****	****pixels style readout****	**
**	****Threshold = 2000 e****-**** ?**

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

##    Detector Materials for sLHC RD39, RD42, RD50, ... 

| Material |  | Progress |
| --- | --- | --- |
| Si  | ~ RT | Trapping/ Annealing at Liverpool, 
N-on-p, MCZ (?) will have meeting in late Feb. in Trento
To discuss RD50 detector production run (short strips?)
(G. Casse arganizer): 
Liverpool, Helsinki, INFN, Barcelona, CERN, UCSC
Compare experience with new Si materials, need input |
| Si -75m | Epi | Trapping same as in bulk, although somewhat less than initially assumed  |
| Si | Cryo | Cryo Engineering: Archival data shows trapping? |
| Si | 3-D | S. Parker, Glasgow, Trento very active |
| SiC | Epi | No signal after 1015 |
| Diamond | Poly | Trapping observed, comparable to Si |
| Diamond | Single
X-tal | Large variance in performance, 
no (high fluence radiation) measurements, yet |

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

##    Detector Materials for Pixels for R  5 cm 

| 
Material |  | Collected Signal [e-] |  | 
Issues |
| --- | --- | --- | --- | --- |
|  |  | Pre-Rad | 1016cm-2 |  |
| Si  | ~ RT | 24,000 | ~ 2,500 | Depletion, Trapping |
| Si -75m | Epi |  6,000 | ~ 2,000  | Small signal at intermediate fluences  |
| Si | Cryo | 24,000  | ? | Cryo Engineering |
| Si | 3-D | 24,000 |  ~ 10,000  | Efficiency “Holes”? |
| SiC | Epi | 2,000 | ~ 0 | Trapping? Slow collection
Cost of wafers |
| Diamond | Poly | 8,000 | < 3,000 ? | Trapping ? Cost of wafers |
| Diamond | Single
X-tal | 12,000  | “Same as Poly ?”  | Trapping ? Cost of wafers |

-    Results from **RD39, RD42, RD50, ... **

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

## Charged Trapping in Si: the Good News

**Efficiency of Charge Collection in 280 um thick p-type SSD**
- G. Casse et al., (RD50):  After 7.5 *1015 p/cm2, charge collected is > 6,500 e-

- Charge collection in Planar Silicon Detectors might be sufficient
- for all but inner-most Pixel layer?
- For 3-D after 1 *1016 n/cm2, predicted charge collected is 11,000 e-

- Trapping Time is factor 2 longer than extrapolated from previous measurements (Krasel et al.)

- No (adverse) anti- annealing observed!
- (P.P. Alport, 2004 IEEE)

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

## Signal / Threshold : Expected Performance

| 
Radius
[cm] | 
Detector | 
Threshold
[e-] | Signal / Threshold |  |  | 
Comment |
| --- | --- | --- | --- | --- | --- | --- |
|  |  |  | 
Pre-Rad | After
1250 fb-1 | After
2500 fb-1 |  |
| > 55  | Long strips | 6250 | 3.7 | 3.7 | 3.7 | ~SCT n-on-p |
| 20 - 55 | Short strips | 4400 | 5.3 | 3.9 | 3.2 | n-on-p |
| 8 cm | Thick Pixel | 2000 | 11.5 | 5.5 | 3.0 | n-on-p |
| 5 cm | Thin Pixel | 2000 | 3.0 | 1.5 | 1.0 | Epi 75 m |
| 5 cm  | 3-D | 2000 | 11.5 | 7.5 | 5.0 | 100 m cells |

**Signal / Threshold : Expected Performance**

**Efficiency in CMS Pixels **
**(T. Rohe, RESMDD04)**** **
- After radiation damage from a fluence of 6*1014 neq/cm-2,
- inefficiency vs. the signal-to-threshold ratio S/T:
- (depends on B-field, pixel size etc, but serves as a guide):
- 			                  Need S/T >  4 - 5

| S/T | Inefficiency 
[%] |
| --- | --- |
| 6 | 1 |
| 4 | 2 |
| 3 | 3 |
| 2 | 7 |

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004

## Signal / Threshold : Expected Performance

- Signal/Threshold
- x Pre-rad
-  Post 2500 fb-1

- Hartmut F.-W. Sadrozinski "Tracking Detectors for the sLHC"                5th STD Hiroshima June 2004