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Re: Si PMs proposal
On Wed, 16 Jan 2008, Elton Smith wrote:
Dear Elton,
some small remarks below.
cheers elke
>
> HI Zisis,
>
> Just responding to the question of the latest SiPM proposal. I agree we
> need a smaller group, and also a draft sow from our side to clarify what
> we would like to see. Here is my initial reaction to the draft 4.1 from
> SensL. Some of these comments support Elke's previous response.
>
> p. 6, should be called gain uniformiy (not optimization)
> - goals are clear
> - should the wafer level testing not come first?
>
> p. 7.
> The following statement "This (0.2 volts variations) is not thought to
> be sufficient a variation to provide for the that are seen at the
> glass array package level." is not supported by Carl's measurements. We
> need to make sure we clarify this with Carl Jackson. If you look at slide
> 32 from George's presentation at the collaboration meeting, Carl's
> measurements show that the gain changes from 240 down to 80 from a change
> in bias from 1.1 down to 0.9V (this is a factor of 3). If we believe it
> scales as a ratio to the voltage over breakdown, then for a nominal
> setting of 2V, 0.2 V variation might be reduced to 1.5 (50%). These are
> substantial changes in gain. Clearly other factors in the variation of
> gain need to be checked but the tracking changes in breakdown voltage
> should be further quantified.
>
I totally agree and that was my point for Page 6 point 3 WP1
> p. 9 and 10: Work Packages 2 and 3: Crosstalk and Trenching
> These are important issues, but in a priority list I would put them after
> the issue of timing. This is because at the moment these do not seem like
> they are limiting their use.
for Trenching I totally agree. But as discussed we would like to see the
electrical cross talk between the 3x3mm^3 SiPMTs of an array.
I mentioned this already during the meeting with Carl Jackson, we can
easily address this with the arrays which have not all the individual
3x3mm^3 SiPMTs summed. But that does not need any development. Si arrays
are also very important for the gain uniformity studies.
>
> p. 11, Timing resolution
> It is claimed that "SensL has demonstrated that it is possible to achieve
> intrinsic timing resolution capability ... on 1mm SPM." I would like to
> see this data; it might have been shown but I missed it. It is still my
> concern that this is an issue. And we clearly need to proceed beyond the 1
> mm SPMs to 3x3mm2 for verification before applied to the SPM arrays.
I don't think we have seen this for bigger SiPMTs.
>
> Here the deliverables emphasize the electronics, but initially the
> intrinsic timing should be verified without electronics. The electronics
> should be checked separately, and I am confident that this can be achieved
> with a proper design.
absolutely, this should be easy to do if we have the arrays with the nice
connectors we saw.
>
>
> Once we agree on the priorities, we can put together a draft sow.
>
I think gain and timing are of highest priority, what I'm a bit suprised
is there is no mentioning of dark counts at all.
Trenching and cross talk on pixel level and on electronics level is for
sure the lowest one.
>
> Cheers, Elton.
>
>
>
>
> > SensL and Proposal
> > ================
> >
> > Elke, for this meeting we need a smaller group of people (you, Elton,
> > George, Andrei, Carl and possibly Fernando). Can you guys propose a
> > time to discuss the new SensL proposal? Friday or Monday afternoon
> > would be ok for Andrei and me.
> >
> > Cheers, Zisis...
> >
> >
> > >
> > >> Date: Tue, 15 Jan 2008 17:17:42 -0600
> > >> From: Zisis Papandreou <zisis@uregina.ca>
> > >> To: Hall-D Collaboration <halld-collab@dustbunny.physics.indiana.edu>
> > >> Subject: [GlueX] Calorimetry Group Meeting - Jan 18
> > >>
> > >> Hello folks:
> > >>
> > >> I have two issues in this email.
> > >>
> > >> 1. Day of the week and time of our periodic Calorimetry Group
> > >> Meetings. There is a suggestion from JLab to reserve Friday's at
> > >> 10-11am for our meetings. This does not mean that we will have a
> > >> meeting every week, it is just that we are trying to find a time that
> > >> works for all active participants of our group, considering the 8
> > >> time zones between Regina through the East Coast to Athens (9 in the
> > >> summer, but we will revisit this at the time).
> > >>
> > >> Please let me know if this time slot does not work for you.
> > >>
> > >> 2. I would like to schedule a meeting this Friday, Jan 18, so please
> > >> reply to question 1 right away. The meeting is tentatively scheduled
> > >> for 10am, unless I hear an uproar. The main topic is the work
> > >> towards the Calorimetry Document, but other issues can be discussed.
> > >>
> > >> http://www.jlab.org/Hall-D/software/wiki/index.php/January_18%
> > >> 2C_2008_Calorimetry
> > >>
> > >> Cheers and thanks, Zisis...
> > >>
> > >> ---
> > >> Dr. Zisis Papandreou | email: zisis@uregina.ca
> > >> Department of Physics | tel. : (306) 585-5379
> > >> University of Regina | tel. : (306) 585-4149
> > >> Regina, SK S4S 0A2 | fax. : (306) 585-5659
> > >> World Wide Web: http://www.phys.uregina.ca/sparro/zisis/
> > >>
> > >>
> > >>
> > >
> > > ( `,_' )+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=
> > > ) `\ -
> > > / '. | +
> > > | `, Elke-Caroline Aschenauer =
> > > \,_ `-/ -
> > > ,&&&&&V Jefferson Lab +
> > > ,&&&&&&&&: HALL-D 12C / F381 121-A Atlantic Avenue =
> > > ,&&&&&&&&&&; Mailstop: 12H5 Hampton, VA 23664 -
> > > | |&&&&&&&;\ 12000 Jefferson Ave +
> > > | | :_) _ Newport News, VA 23606 Tel.: 001-757-224-1216 =
> > > | | ;--' | Mail: elke@jlab.org Mobil: 001-757-256-5224 -
> > > '--' `-.--. | +
> > > \_ | |---' Tel.:
> > > 001-757-269-5352 =
> > > `-._\__/ Fax.:
> > > 001-757-269-6331 -
> > > +=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-
> > > +=-+=-+
> > >
> >
> > ---
> > Dr. Zisis Papandreou | email: zisis@uregina.ca
> > Department of Physics | tel. : (306) 585-5379
> > University of Regina | tel. : (306) 585-4149
> > Regina, SK S4S 0A2 | fax. : (306) 585-5659
> > World Wide Web: http://www.phys.uregina.ca/sparro/zisis/
> >
> >
> >
>
>
( `,_' )+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=
) `\ -
/ '. | +
| `, Elke-Caroline Aschenauer =
\,_ `-/ -
,&&&&&V Jefferson Lab +
,&&&&&&&&: HALL-D 12C / F381 121-A Atlantic Avenue =
,&&&&&&&&&&; Mailstop: 12H5 Hampton, VA 23664 -
| |&&&&&&&;\ 12000 Jefferson Ave +
| | :_) _ Newport News, VA 23606 Tel.: 001-757-224-1216 =
| | ;--' | Mail: elke@jlab.org Mobil: 001-757-256-5224 -
'--' `-.--. | +
\_ | |---' Tel.: 001-757-269-5352 =
`-._\__/ Fax.: 001-757-269-6331 -
+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+=-+