# Presentation: 413857

## Mineral Oil Tests for the MiniBooNE Detector

- Jennifer L. Raaf
- University of Cincinnati
- November 8, 2001

-  Overview of MiniBooNE Experiment
-  Detector
-  Event Signatures
-  Attenuation Tests
-  Cincinnati Tester
-  Alabama Tester
-  Index of Refraction Measurements
-  Fluorescence Test
-  Other Oil Tests
-  Summary

## The MiniBooNE Collaboration

- I. Stancu
*University of Alabama, Tuscaloosa, AL 35487*

- S. Koutsoliotas
*Bucknell University, Lewisburg, PA 17837*

- E. Church, G. J. VanDalen
*University of California, Riverside, CA 92521*

- E. Hawker, R. A. Johnson, J. L. Raaf, N. Suwonjandee
*University of Cincinnati, Cincinnati, OH 45221*

- L. Bugel, J. M. Conrad, J. Formaggio, J. M. Link, J. Monroe,
- M. H. Shaevitz, M. Sorel, G. P. Zeller
*Columbia University, Nevis Labs, Irvington, NY 10533*

- D. Smith
*Embry Riddle Aeronautical University, Prescott, AZ 86301*

- C. Bhat, S. J. Brice, B. C. Brown, B. T. Fleming, R. Ford, F. G. Garcia, P. Kasper,
- T. Kobilarcik, I. Kourbanis, A. Malensek, W. Marsh, P. Martin, F. Mills,
- C. Moore, E. Prebys, A. Russell, P. Spentzouris, R. Stefanski, T. Williams
*Fermi National Accelerator Laboratory, Batavia, IL 60510*

- D. C. Cox, A. Green, H.-O. Meyer, R. Tayloe
*Indiana University, Bloomington, IN 47405*

- E. D. Zimmerman
*University of Colorado, Boulder, CO 80309*

- R. Imlay, A. Malik, W. Metcalf, M. Sung, M. O. Wascko
*Louisiana State University, Baton Rouge, LA 70803*

- G. T. Garvey, W. C. Louis, G. B. Mills, V. Sandberg, B. Sapp,
- R. Schirato, R. Van de Water, D. H. White
*Los Alamos National Laboratory, Los Alamos, NM 87545*

- J. Cao, B. P. Roe
*University of Michigan, Ann Arbor, MI 48109*

- A. O. Bazarko, P. D. Meyers, R. B. Patterson, F. C. Shoemaker
*Princeton University, Princeton, NJ 08544*

- P. J. Nienaber
*College of the Holy Cross, Worcester, MA 01610*

## The MiniBooNE Detector

- Two stage experiment currently under construction at Fermilab
- Designed to search for neutrino oscillations
- Oil Čerenkov detector
- 12 m diameter carbon steel sphere
- 250,000 gallons of mineral oil
- 1280 photomultiplier tubes (PMTs) detect scintillation
-     and Čerenkov light

- Mini Booster Neutrino Experiment

## MiniBooNE Event Signatures

**Čerenkov light: prompt and forming rings**

**Scintillation light: **
**            ****late and isotropically distributed**

## Why Mineral Oil?

- No expensive filtration system needed as with water detectors
- Density provides more targets for neutrino interactions

- Several important tests were performed
- to aid in the decision of which oil to use

-  Attenuation length
-  Density
-  Index of refraction and dispersion
-  Fluorescence

## Cincinnati Attenuation Tester

**Monochromator**

**Deuterium light source**

**Reference PMT**

**Test PMT**

- Oil sample

-  Data taken are the ratio of
-  Test range is 3000-5000 Å in steps of 10 Å
-  ~ 90% of the light travels through oil sample
-  ~ 10% light travels to reference PMT
-  Setup provides ***relative***** **attenuation length of       different oils and ***shape**** *of transmission curve

- (EMI 9813)

- (EMI 9813)

## Cincinnati Tester Results

- Reproducibility of
-  runs

- Ten oils tested
-  very different
- 	shapes
-  very different
- 	absorption
- 	features

## Alabama Attenuation Tester

- WALL

- Blue LED
- 460 nm

- Collimator
- Lens

- Stainless
- steel pipe

- XP2264B
-       PMT

- Beaker

- Valve

- Lexan
- Fluid
- Level
- Indicator

-  Attenuation length determined by
-   measuring intensity of blue light
-   as a function of path length in oil
-  Goal: measure attenuation lengths
-    as large as 20 m with an error better
-    than ±2.5 m.
-  Since this tester has only a
-    1 m path length, must measure
-    light intensity with an accuracy
-    of better than 1%.

## Alabama Tester Results

| Oil Sample | Atten. Length (m) FIT | Date tested |
| --- | --- | --- |
| Telura 622 | 2.21 ± 0.01 | 9/6 |
| Superla 7 | 9.84 ± 0.09 | 9/4 |
| Witco | 10.79 ± 0.11 | 8/31 |
| Duoprime 90-2 | 12.76 ± 0.14 | 9/4 |
| Duoprime 70 | 13.96 ± 0.16 | 9/5 |
| Duoprime 90-1 | 14.33 ± 0.19 | 8/31 |
| Marcol 10 | 14.52 ± 0.18 | 9/12 |
| Parol 80 HP-C | 15.41 ± 0.21 | 9/5 |
| Marcol 9 | 23.65 ± 0.46 | 9/5 |
| Marcol 7 | 26.45 ± 0.59 | 9/6 |

## Index of Refraction Measurements

- Mercury line
- source

- Spectrometer
-        table

- Equilateral
- Plexiglas
- container

-  Container rotated on table until
-   minimum deflection observed
-  Index of refraction measured
-   for six lines of the mercury
-   spectrum

-  Indices of refraction are fit to a “one resonance” model
-   for dense media

## Density and Index of Refraction

-  Density and index of refraction directly
-    related

## Fluorescence Test

-  Fluorescence tests performed on 3 cm3
-   volume sample of  oil to check for unusual
-   features
-  All oils tested were “normal”

## Other Oil Tests

-  Two different scintillation tests in progress
-  Needed to understand inherent
-    scintillation properties of chosen oil
-  May add organic scintillator to chosen
-    oil at a later date
-  Allows for controlled amount of
-     scintillation light
-  Ensures known value of scintillation
-     timing for use in event reconstruction

## Summary

-  Several factors played into the decision
-   of an oil for the detector
-  Attenuation length
-  Index of refraction and density
-  Fluorescence
-  Need to understand other properties of
-   the chosen oil
-  Scintillation
-  Important to understand the properties
-   of the chosen mineral oil very well to
-   aid in event reconstruction