Some discussion and homework. I keep adding to this. The previous version is in the FPF technical meeting from may 24.
https://indico.cern.ch/event/1419868/
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*** It is important that we now have a discussion and agreement with CERN cryogenics people that the horizonal insertion cryostat is acceptable
and there is a solution to the liquid argon storage tank. And we also may need LN2 storage at the bottom.
** Next Friday 8:30 meeting June 7 will be important and Jamie will attempt to get Johan Bremmer to come to the meeting.
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[Y] Connor will make sure all drawings from Larry and Steven Trabocchi have been converyed to Anastasiya.
Connor has the Trabocchi platform. Get it from Trabocchi.
0) Get information from Jetseals - Larry
Connor will contact Larry and Jetseals to understand what is needed to make further progress.
"I believe we can make a seal to fit a cavity close to what is drawn up. I do have a concern with the leak rate. Everything leaks, the challenge is getting it small enough that it is manageable. There is a lot of seal line for a small flaw to create a leak just large enough to create an issue. We will have to check for to see if we can find a tin plating tank large enough. "
Steve Hudlet, PE, Engineering, JETSEAL, Inc.
Larry will close the gap with Connor that we are waiting to make the dimensions more firm. Wait until the meeting with Johan ?
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Is the Kostas optical readout compatible with horizontal insertion ? Can we talk to Kostas about horizontal installation ?
Otherwise we have to keep two cryostat options open coupled to readout technology.
Need to engage Kostas in one of the meetings either Tuesday or Friday morning.
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1) Conceptual design and options for electronics -- Steven is arraning a meeting with Sergio, Aleksey and others.
Prafull Purohit is spending some time understanding QPIX design. The power cost of QPIX is very low ~ few microwatts.
A document has been written to summarize where we are. This is attached in https://indico.cern.ch/event/1419868/
A design for the anode is needed with some tentative calculations of the heat load and performance. --- ALEKSEY ?
TGhe text is for the Technical report being written.
2) Cabling options to get cables across to the feedthroughs. -- Everyone ?
The one unique aspect to FLARE TPC design is that the cables have to cross over TPC modules. This means the grounding planes have to be considered
to make sure there is no field in the place where cables must go. Cables = copper cables.
We could consider all optical readout, but we must then also consider optical power. Power and readout must be done over fiber.
A new paper from DUNE is circulating about this development. We should use it.
3) Concepts for light readout. -- Jianming ? Trigger ? Time tagging for LHC bunch.
New SIPMs are VUV sensitive down to 120 nm with 10% efficiency
BNL has ordered 18 units at $250 each. We need to get these tested in Yichen's LAR chamber.
We need to design a board and readout and some feedthrus ?
Will send spec to this list.
4) Electrical field calculations in the gap -- Yichen using comsol.
Comsol -- can it use stp files ? This module apparently costs $8000 per year.
BNL will get the module for STP files. This is a single person license.
*** Aleksey communicate with Yichen for the pixel options.
5) electrical field calculation in special positions near the cathode -- Yichen using comsol
Yichen will communicate with Jamie Boyd about using Comsol at CERN. And what is needed in terms of getting access as well as putting in the
correct design data.
**** communicate with Kostas and see if he needs help with such a calculation for his optical readout.
6) Some simulations studies to understand the fiducial losses due to gaps. -- Matteo/ Wenjie
Pixel simulation ? -- full simulation is not ready yet, but an effective simulation could be done with just different binning.
--- Put some deadlines and get the simulation note finished.
--- Get comments on simulation note by May 15.
We need to work on reading this simulation paper.
Put the read only link to overleaf here: https://www.overleaf.com/read/vpbyqcycftpy#9eb3de
7) Settle on a very small prototype / using BNL 260 liter system ?
--- Keep it < 10 cm drift. 16 channels of pixels, and 8 channels of SiPMs.
--- Readout out of the liquid.
--- Aleksey ?
Aleksey, Connor and Yichen will work together to make a drawing or idea for a small prototype
Focus can be generic: use of Version-4 VUV SiPMs and also investigation of the diffusion limited spatial resolution with pixels ?
Yichen's meeting: add others.
New item
8) Anastasia noticed that there is currently 800mm between the edge of the FLArE cryostat and the FLARE HCAL. Can this be reduced? If so, what is the minimum distance we could have for that?
Temporary Answer:
The HCAL needs to go through a real design. Recall we were going to use the design of Baby-MIND that was provided to us by Franck Cadoux. We do not yet know what is required by Franck’s design of Baby-MIND in terms of space between the cryostat and the HCAL.
And so, the answer is probably yes, we can reduce the 800 mm, but we do not know by how much until we do a detailed design. Also, we still do not know what is needed insulation of the new cryostat. Given both uncertainties, I would leave it as it is for now, but mark it for future reduction.
Larry will look through Franck's STp file