# Presentation: 307332

## Cost of aLarge Solid Scintillator Detector

- Jeff Nelson
- Fermilab

## Starting Comments

- MINOS had many cost drivers
- Many things to work on for OA detector
- A number of things to change before we have a reoptimized detector
- MINOS had too much light (9 pe vs 4.7 pe)
- MINOS optimized for the scale
- Significantly more area changes the optimization between labor and automation
- LoDen (water or organics) makes a big difference in the amount of instrumentation (~3x)
- Steel design easy but silly if anything else feasible

## Adiabatic Optimization

- 5.4kt, 8m x 8m, 2.54cm Fe, M16
- 2) 20kt, 12m x 12m, 5mm Fe, M16 (for reference)
- 3) 20kt, 12m x 12m, 15cm particle board, M16
- 4) 20kt, 20m x 20m, 15cm PB, VLPC (high QE)
- 5) 20kt, 20m x 20m, 15cm PB, IIT
- 6) 20kt, 20m x 20m, 15cm H20, IIT (low QE)
- #5 for strawman solid scintillator design
- #6 for comparison with the liquid scintillator

## Case 1:MINOS Far Detector ($M)

- Scintillator strips	3.2
- Module parts/labor	5.3
- Fiber	3.6
- PMTs/hardware	3.0
**Scintillator subtotal****	****15.1**
- Channel electronics	4.5
- Steel	4.5
- Detector installation	4.8
**Far Detector total*****	****29.9**

***Other Costs**
- Coil, calibration	2.1
- Management	2.0
- Cavern/Outfitting	13.9
**Grand total****	****46.9**
**Actives (no install/steel)**
**	****= $19.6M/26,600m****2**
**	****= $736/m****2**
**	**

## Extrapolation to Fine Grain

- Move from “HCAL” to “ECAL”
- 2.5 cm sampling 		 0.5 cm (~X0/3)
- 4.1 cm strips 			 OK?
- 5.4 kton			 20 kton
- Too much light (2x)!
- Can to do the physics with ~4.7 pe
- We have 9 pe
- We could save $ at expense of light...
- Reduce fiber diameter (light  diameter; $  area )
- Reduce strip thickness (light  thickness; $  thick.)
- Increase plane diameter (~6m atten. length)
- N.B. atten length is longer the further along the fiber you go
- A 12m square would still have enough light

## Cage 2HiDen Extrapolation

- Fine-grained
- 0.5 cm steel
- Make 20 kton
- 12m x 12m x 50m
- Other assumptions
- Assume Doug’s 20% volume discount
- Make 2m-wide modules
- Vitals
- 490,000 m2 (19x MINOS)
- Actives $414/m2

- Scintillator	 $47
- Modules/labor	 $45
- Fiber	 $53
- PMTs	 $25
- Electronics	 $33
- Steel	 $18
- _Installation__	__ $23_
- Total	 $245M

## Case 3LoDen Solid Scintillator

- Reduces area of instrumentation by about factor of 3
- 165,000m2
- About 6x MINOS
- Assume monolithic particle board absorber
- Self supporting
- Installation very similar to MINOS
- Can support the scintillator in same method at MINOS
- Construction industry good at making things with wood cheaply
- Lots of cartage loaded screw guns instead of welding
- PB costs guessed from another speaker

- Scintillator	 $16
- Modules/labor	 $15
- Fiber	 $18
- PMTs	 $9
- Electronics	 $11
- Part. Board	 $6
- _Installation__	__ $8_
- Total	 $82M

## Case 4 Example High QE Detector : VLPC

- Alan Bross used DØ VLPCs to look at MINOS strips
- Sees 48 pe per MIP
- Quotes D0 devices at $50 per 1mm2 pixel
- Can subdivide at cost of more electronics
- Can
- Thin scint to 5mm
- Thin the fiber 0.6mm
- Lengthen the strip to 20m
- ... still have enough light
- However
- You loose the 8X optical summing so Elec. costs up by 5x
- Get about the same cost but better fiducial fraction

## Case 5My Strawman

- Use 10m long strips with MINOS geometry
- 2 Single ended readout with 0.7mm fibers and mirrors
- 60% like MINOS ND
- Put modules end to end to make 20m square
- 15cm of particle board between layers
- Alternating views
- 410 planes
- IIT readout ($3500/plane)
- 4 readout stations on each face to reduce clear fiber
- Need something like MINOS PMT box for IITs (~1k$)

## Case 5 Strawman Solid Scintillator Costs

- 6.2x MINOS area
- Active cost $172/m2
-  (including all readout)
- IITs make this affordable

- Scintillator	 	$ 7.6
- Modules/labor	$11.2
- Fiber	 		$ 6.0
- IITs			$ 2.9
- Electronics	 	$    -
- Absorber	 	$ 6.0
- _Installation__	__ __	__$ 2.7_
- Total	 	 	$36.8M

## Case 6Adopt Ken’s Geometry for Comparison

- 0.5mm fiber
- Double fiber
- Read each fiber on single end
- IITs
- Water cells for absorber
- Active cost $192/m2
-  (including all readout)

- Scintillator	 	$15.8
- Modules/labor	$11.2
- Fiber	 		$ 3.1
- IITs			$ 1.4
- Electronics	 	$    -
- Absorber	 	$  2.1
- _Installation__	__ __	__$  2.7_
- Total	 		$36.4M

## All Cases

## How to House?

- Do we need an overburdon?
- If not building could be cheap
- e.g. At MSP Sun Country has Hanger with flexible sides
- Use free standing bridge crane
- Support walk ways off the the particle board
- Should look into costs
- Some minimal climate control and modular housing for the counting offices and DAQ