Speaker
Dr
Erik Ramberg
(Fermi National Accelerator Laboratory)
Description
Future calorimeters and shower maximum detectors at high luminosity accelerators need to be very radiation resistant and very fast. In this report we outline the study of the development of such detectors using microchannel plate (MCP) secondary emitters. The first proposal to use secondary emitters in such a detector can be found in Ref. [1]. Our research is based on the use of MCP secondary emitters as active elements that directly amplify the electromagnetic component in showers. A key point is that the method does not require a complete MCP/phototube with photocathode deposited on a vacuum glass container, but can use the bare MCP’s in an inexpensive and robust housing. As the photocathode fabrication is the dominant driver of the cost of current MCP-PMTs, the use of bare plates without a photocathode results in much cheaper and more robust assembly. One of the main limitations in using this technique has been the high cost of MCPs. Due to recent progress in developing MCP’s consisting of large-area glass-capillary substrates functionalized by Atomic Layer Deposition [2, 3], this approach is becoming feasible.
Test beam measurements of a prototype were performed with 120 GeV primary protons and secondary beams at the Fermilab Test Beam Facility. We present proton and positron beam tests results, obtained with different type of MCP-PMT’s. Beam particles pass through a lead absorber of varying thickness, creating a shower that is detected by the MCP-PMT’s. We report here on the timing characteristics obtained in the beam tests, the dependence of the pulse amplitude on the absorber thickness, and the contribution of the Cherenkov component from the shower interacting with varying thicknesses of quartz placed in front of the MCP-PMT. We have measured a shower maximum time resolution of ~25 psec, using the DRS4 5 GS/s digitizer. [4]
*corresponding author
References
1. A. Derevshchikov, V. Yu. Khodyrev, V.I. Kryshkin, V.E. Rakhmatov, A. I. Ronzhin, “On possibility to make a new type of calorimeter: radiation resistant and fast”. Preprint IFVE 90-99, Protvino, Russia, 1990.
2. O. H. W. Siegmund, J. B. McPhate, J. V. Vallegra, A. S. Tremsin, H. Frisch, J. Elam, A. Mane, R. Wagner, “Large Area Event Counting Detectors with High Spetial and Temporal Resolution” to be submitted to JINST; Dec, 2013.
3. Incom. Inc; Charlton MA, USA
4. Stefan Ritt, “Development of high speed waveform sampling ASICs”, in proceedings NSNI 2010
Primary author
Dr
Anatoly Ronzhin
(Fermi National Accelerator Laboratory)
Co-authors
Dr
Andriy Zatserklyaniy
(UC Santa Cruz, CA)
Dr
Artur Apresyan
(Caltech)
Dr
Erik Ramberg
(Fermi National Accelerator Laboratory)
Heejong Kim
(University of Chicago)
Prof.
Maria Spiropulu
(Caltech)
Dr
Sergey Los
(Fermi National Accelerator Laboratory)
Dr
Si Xie
(Caltech)
