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PID consortium: homework

M. Alfred, M. Awadi, B. Azmoun, L. Allison, F. Barbosa, W. Brooks, T. Cao, M. Chiu, I. Choi, M. Contalbrigo, A. Datta, C.L. da Silva, M. Demarteau, J.M. Durham, R. Dzhygadlo, D. Fields, M. Grosse-Perdekamp, C. Han, J. Harris, X. He, H. van Hecke, T. Horn, J. Huang, C. Hyde, Y. Ilieva, G. Kalicy, E. Kistenev, Y. Kulinich, J. Lindesay, M. Liu, R. Majka, J. McKisson, R. Mendez, P. Nadel-Turonski, K. Park, K. Peters, R. Pisani, Yi Qiang, S. Rescia, P. Rossi, M. Sarsour, C. Schwarz, J. Schwiening, N. Smirnov, J. Stevens, A. Sukhanov, J. Toh, R. Towell, T. Tsang, Ji Wang, R. Wagner, C. Woody, W. Xi, J. Xie, L. Xue, N. Zachariou, Z. Zhao, B. Zihlmann, C. Zorn.

Generic Detector R&D for an Electron Ion Collider

Advisory Committee Meeting, BNL, July 9-10, 2015

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Please provide a prioritized list of the proposed FY16 projects• TOF

– The UIUC postdoc is the only request and is a high priority

• RICH– The simulation effort (postdocs at GSU and INFN) forms the basis for making all

hardware decisions at a later stage and is thus a high priority.

– The prototyping and beam testing of the modular aerogel RICH is essential for validating the concept, but could be postponed to FY17.

– The GEM photocathodes could offer exciting opportunities, but since the modular RICH could use LAPPDs instead, they are a lower priority.

• DIRC– Analysis of the recent test beam data and simulations of the plate-based

configuration, carried out by the ODU postdoc, are a high priority.

– Note that development of radiation hard lenses and mirror-based readouts are important, but the activities are not planned until FY17-18

• Sensors in magnetic fields– The continued testing of MCP-PMTs in magnetic fields is a high priority, but we can

reduce the number of test runs in FY16 from two to one.

• LAPPDs– The development of LAPPDs (ANL postdoc) is important for many PID systems, and

thus in general a high priority, but procurement of an UV spectrometer may not be necessary

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We consider all four R&D topics (TOF, RICH, DIRC, and sensors) critical for the development of an integrated hadron ID system for the EIC central detector. Furthermore, we think that it is essential to keep the know-how of the postdocs (and their supervisors) currently working on the project. This is reflected in the priority list on the previous slide.

• $70k for UV spectrometers for RICH prototyping and LAPPDs (GSU, ANL)

• $69k for GEM photocathode project (UNM)

• $10k for one high-B test run (JLab/USC)

• $8k for undergrad for high-B test (CUA)

• $25k for modular RICH prototype and beam test (GSU, LANL, BNL)

• Additional travel which was not already included in above items

Possible FY16 budget adjustments

Based on the prioritized list, in case budget cuts are made, we would suggest the following order (top to bottom)

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Hadron Endcap

• The requirement for π/K/p ID up to ~50 GeV/c favors the use of a gas RICH in combination with supplementary detectors covering lower momenta.

• For high momentum range (π/K separation of 10<p<50 GeV), gas-radiator RICH will be used. Current options are a single-radiator device (such as the one developed by eRD6 and used in ePHENIX design), or a dual-radiator (aerogel-gas) RICH. For the latter, the preferred option is configuration of mirror focusing (LHCb RICH like), but a comparative study with a proximity focused option will be made.

• For the lower momentum range (π/K separation of p<10 GeV) The success of the ps-TOF and modular aerogel RICH R&D will determine whether an aerogel-gas RICH is preferable to a ps-TOF system or modular aerogel RICH (used in combination of eRD6 gas RICH for the higher momentum range).

• The preferred option will specifically be benchmarked against the currently proposed ePHENIX configuration of a gas RICH (eRD6) supplemented by a ring of modular aerogel RICH detectors.

How do you see the process of selecting the various technologies investigated towards a final PID scheme for an EIC detector?

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Electron Endcap• The lower momenta (p < 10 GeV/c) of hadrons on the electron side make

the compact, modular aerogel RICH a very attractive alternative to a threshold Cherenkov device – in particular if the readout could also serve as a TOF device providing a reference signal (using electrons scattered into the endcap).

• The key question here is sensor cost, and the success of the LAPPD R&D will decide whether an aerogel RICH can offer a cost-effective alternative.

How do you see the process of selecting the various technologies investigated towards a final PID scheme for an EIC detector?

Central Barrel• The baseline solution is a radially compact combination of TOF and

DIRC. Due to the short flight path in the barrel, we expect that the DIRC will offer better performance than even a ps-TOF. However, ps-TOF could improve the operation of the DIRC.

• A complete ps-TOF coverage would also provide high-resolution track-to-track relative timing independent of external start signals. At the 80 ps level, this is the preferred method used for CLAS12.

• It could also be possible to use a modular aerogel RICH in the barrel, but the sensor area would become very large .

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• Alessio Deldotto

– Institution: INFN, Frascati, Rome

– Supervisor: Everisto Cisbani

– Topic: dual-radiator RICH

Provide a list of postdocs

• Grzegorz Kalicy

– Institution: ODU

– Supervisor: Charles Hyde

– Topic: DIRC

• Ihnjea Choi

– Institution: UIUC

– Supervisor: Matthias Grosse-Perdekamp

– Topic: ps-TOF

• Jingbo Wang

– Institution: ANL

– Supervisor: Bob Wagner

– Topic: LAPPDs

• Liang Xue

– Institution: GSU

– Supervisor: Xiaochun He

– Topic: modular aerogel RICH

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•   What is the involvement of the group in the Panda  test beams analysis?

• Post Doc Greg Kalicy (ODU) and ODU grad student Lee Allison (funded separately) are leading this analysis.

• When are the test beam results expected?

• Within FY16

• How do results of the test beam feed into the technology choices for an EIC?

• Validating the 6 mm pixel simulation with data will enhance confidence in the 2 mm pixel simulation.

• The fine-angle step scan also partially removes the pixel size effect.

• Test beam data provides guidance on the tradeoffs between bars and plates.

• What pubications are expected?

• We expect Conference Proceedings in FY16 on both the DIRC simulations/test beams and the High B-field tests.

• We expect NIM publications in FY16 or 17 on both topics also.

DIRC (eRD4) specific questions

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RICH (eRD11) specific questions

ERD11 publication plans:

After the completion of the proposed beam testof the modular RICH, which may be postponed to FY17,we expect to publish a NIM paper on the detector conceptand the test results.

TOF (eRD10) specific questions on the following slides

How do you arrive at the numbers in table 2-3, especially the NPEs?

1 cm

Calculating N.P.E.

CKOV spectrum:

Then integrate:

Transmittances:

QE:

MgF2UV fused silica

Boro330

A controversy over K2CsSb?J. Smedley calculation

Junqi Xie measurement

“One of the interesting things I learned at the Picosecond Photon Sensor Workshop last week in Prague was that bialkali (presumably K2CsSb) photocathodes while having a fall-off at shorter wavelengths (say below 350nm), exhibit a rise in QE below 250nm. They, in fact, can have their largest QE below 200nm! Serge Pinto from Photonis gave a presentation on Wednesday June 10 just before I headed to the airport to go to Geneva. He showed a plot of a measurement of QE versus wavelength and noted that this rise had been predicted but had not been measured before. The data showed QE peaking up to ~30% I believe. Unfortunately, his talk is not obtainable from the workshop Indico agenda page. I did a search on VUV response of bialkali photocathodes and found the attached paper. I refer you to figure 9 and the text starting on page 546, section IV subsection A. PMTs. They measured this rise for a Phillips tube and gave a reference to another paper showing an even larger peak. So it seems as though at least two groups have previously seen this phenomenon. The paper is also interesting in that its main subject was measurement of UV and VUV response of bialkali tubes a low temperature. It is worth reading.”

email from Bob Wagner

Araujo et al, IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 4.5, NO. 3, JUNE

1998

Please provide a list of publications, submitted or planned. For the latter list topic and timeline.

There are no publications yet but we plan on

1. NIM on results from 36 gap glass mRPC built at UIUC, ~Fall 2015

2. NIM on alternative materials mRPCs, expect test beam data in April 2016 (piggy-backed off a planned sPHENIX beamtest), ~Summer 2016

3. NIM on Garfield++ simulations of mRPCs, ~Summer 2016

4. Conference paper on physics reach with 10 ps TOF PID for SIDIS, Spin2016