1. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 1 HE CALORIMETER DETECTOR UPGRADE R&D STATUS E. A. Albayrak for The University Of Iowa Fairfield University The University of Mississippi

2. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 2 Outline The Problem, and proposed solution Summary of the previous results –Cerenkov light collection, uniformity, efficiency –Radiation hard quartz plates –Light enhancement option: P-Terphenyl (PTP) The recent R&D update -Quartz type, plate size, fiber geometry, wrapping material issues are settled. New focus is to increase the light production, and solving fiber radiation problem. -We continue to Geant4 simulations on Quartz Plates. -In February 2006, Fermilab Test Beam: The tests of the new fiber geometry, PTP light enhancement tests. -In May 2006, PTP radiation damage studies at IUCF (Indiana University Cyclotron Facility). -Summer 2006 wrapping material reflectivity tests. -September 2006, Fermilab Test Beam: Zinc-Oxide, PTP, and Anthracene are tested.

3. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 3 The “Problem” and the “Solution” As a solution to the radiation damage problem in SuperLHC conditions, quartz plates are proposed as a substitute for the scintillators at the Hadronic Endcap (HE) calorimeter. Quartz plates will not be affected by high radiation. But the number of generated cerenkov photons are at the level of 1% of the scintillators. Rad-hard quartz –Quartz in the form of fiber are irradiated in Argonne IPNS for 313 hours. –The fibers were tested for optical degradation before and after 17.6 Mrad of neutron and 73.5 Mrad of gamma radiation. –Polymicro manufactured a special radiation hard solarization quartz plate.

4. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 4 Pre2006 Conclusion Polymicro special production of “solarization quartz” is radiation hard. Using different fiber geometries, making the quartz thicker (5-6mm), and smaller (10cm x 10cm) increased our light collection up to 25% of the HE scintillator plate. For more light we should increase the amount of fiber in plate. We used plastic WLS fiber with 0.6mm diameter. We haven’t tried a radiation hard WLS fiber. With a bigger diameter we can increase the light collection. The initial simulations showed that light collection uniformity with respect to fiber geometry varies drastically. We should find more uniform fiber distribution. Tyvek is the best option to wrap the plates. It is easy to work, very good UV reflective material. Mylar disintegrates when it is in contact for a long time. PTP raddam tests are promising. If we can dope the plates or wrappers with PTP, we can increase the light collection. The bench tests verifies clear light production increase with PTP. The quartz capillaries and liquid WLS have been tested for Numerical Aperture and attenuation. The results are promising, need improvement on liquid filling techniques, quartz endplugs, and UV transparency.

5. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 5 The “NEW” Geometry

6. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 6 Quartz Plate Simulations O-shape wls Y-shape wls S-shape wls Bar-shape wls We will run uniformity simulations and tests on the Bar geometry.

7. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 7 February 2006 Test Beam The bar geometry collected up to 50%-75% of the light original HE plate. For 66 GeV beam, the cerenkov light collection efficiency drops w.r.t. scintillators.

8. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 8 February 2006 Fermilab Test Beam Results with PTP Two GE quartz plates counter was tested with and without PTP. The PTP was loaded on to the Tyvek wrapper. 20% increase in light yield was observed. We attribute this to the test beam pmt (R1398) It collected light in the visible range. UV enhanced pmts will be used in the CERN Test beam 2006. Higher concentrations of PTP will be applied.

9. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 9 May 2006 PTP Raddam Tests PTP irradiated at Indiana University Cyclotron Facility, in May '06 We reached 10 Mrad level with 200 MeV protons. Samples diluted in Toluene and subjected to C14  source. Counting rates measured vs concentration.

10. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 10 10 MRad 200 MeV protons Little damage observed when compared to unirradiated sample. May 2006 PTP Raddam Tests

11. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 11 Pterphenol Tests Fluorecence analysis performed. Molecular damage observed shifting light from UV to visible! Chemical Analysis of damage under investigation. More Neutron, Proton irradiations Pterphenol Tests

12. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 12 Zinc Oxide Plate Zinc Oxide Readout with Fibers 3 mm thick 6” x 6” Quartz Plate, coated with 9 micron of ZnO which is expected to yield about 300-400 photons The WLS fibers placed on the upstream side, and the ZnO film is on the downstream side of the quartz plate, to reduce Cerenkov light captured in the WLS fibers Sept 06, Fermilab Test Beam

13. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 13 Zinc Oxide

14. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 14 Anthracene and pTerphenyl films Formed from a melt squeezed between pieces of glass The thickness of the glasses 1” x 3” x 1/16 inch. The films are estimated to be ~100 microns thick. They are readout by 2 WLS Fibers are placed upstream. The anthracene has a higher response, estimated to be about 2-3 pe, vs 1-2 pe for the pTP.

15. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 15 Anthracene

16. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 16 pTP

17. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 17 Reflection studies Measurement of the reflective properties of different samples of Mylar, HEM, Tyvek and Aluminum foil. Each sample was mounted on a ring and placed at the end of a light guide. A PMT was mounted at the other end of the PMT to measure light reflected back up the light guide. An optical fiber carried light into the light guide and bounce it off the reflective surface back to the PMT. Levels were measured and compared for each substance. A PMT was mounted behind the reflective sample to collect any light that may pass through the sample. A 337nm Nitrogen LASER was used.

18. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 18 Reflection studies NameThickness (in)Comment: Al0.0010 Opaque to room light; Shiny and Dull side HEM0.0019 Transparent to room light; shiny (white) and dull (dark side) M10.0011 Opaque to room light; shiny (white) and dull (dark) side M20.0010 Transparent to room light; shiny (white) and dull (dark) side M30.0009 Opaque to room light; shiny (white) and dull (dark) side M40.0010 Transparent to room light; shiny (white) and dull (dark) side T10.0138 Opaque to room light; black on one side; T20.0041 Translucent; Shiny and dull side

19. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 19 Reflection studies

20. E. A. Albayrak, HCAL Meeting, Fermilab, Nov. 2006 20 The Future Plans The “generation 1” Quartz Plate Calorimeter prototype is being build with the “NEW” fiber geometry, based on the information we collected during these R&D studies. We have focused on light collection technique. We started from 1% photon production ratio with respect to the original HE scintillators. At the latest design we increased the cerenkov signal from a quartz plate to almost 75% of the original HE scintillator. We will run uniformity simulations and tests at different wavelengths. The parallel studies performed by Missisippi and Fairfield has increased the options we can use on future generations of the Quartz Plate Calorimeter Prototypes. PTP can be used to increase the light 20% more, contingent to the radiation hardness tests. We have not addressed to the radiation hardness of the wavelength shifting fiber, yet. The preliminary plan is to carry the cerenkov photons with quartz fibers and shift it before the light detector (PMT or HPD) via liquid wavelength shifter.