Re: PROBLEM REMAINS with gluex-doc-1300

[semenov@jlab.org]

No, we did not. Yet. But we will today afternoon.

>
> HI Andrei,
>
> Of course the "first layer" for the SiPM option is actually the sum of 3
> of your layers in depth. I assume you did this as well?
>
> Elton.
>
>
>
> Elton Smith
> Jefferson Lab MS 12H5
> 12000 Jefferson Ave
> Suite # 16
> Newport News, VA 23606
> elton@jlab.org
> (757) 269-7625
> (757) 269-6331 fax
>
> On Wed, 15 Jul 2009 semenov@jlab.org wrote:
>
>> Elton:
>>
>> This explanation does not work. The problem is the figures I sent to you
>> contain the sum of numbers from the four cells of the 1st layer (viz.,
>> the
>> maximal signal + all 3 other "not-maximal" signals), and the numbers in
>> the spectra I sent to you are MUCH SMALLER than yours. Also, with
>> selection of the "maximal" signal, you can not go away from the big
>> zero-channel spike: if the sum of four signals is close to zero => the
>> maximal signal is close to zero too.
>>
>> I still think that your figures made using not correct values from the
>> ntuples.
>>
>> Sorry,
>> Andrei
>>
>>
>>
>> >
>> >
>> > Hi Andrei,
>> >
>> > What is plotted is the maximum number (not the sum) in one of the four
>> > cells in the first layer. It is to find the channel that has the
>> maximum
>> > signal. It may not always be the same segment, but we know that at
>> least
>> > one segment has that much energy.
>> >
>> > Cheers, Elton.
>> >
>> > Elton Smith
>> > Jefferson Lab MS 12H5
>> > 12000 Jefferson Ave
>> > Suite # 16
>> > Newport News, VA 23606
>> > elton@jlab.org
>> > (757) 269-7625
>> > (757) 269-6331 fax
>> >
>> > On Tue, 14 Jul 2009 semenov@jlab.org wrote:
>> >
>> >> Elton:
>> >>
>> >> What did you plot in the figure 9 of the gluex-doc-1300 note?
>> >>
>> >> The caption says that it's "maximum number of photoelectrons detected
>> in
>> >> the first layer". What's that?
>> >>
>> >> If you meant the sum of photoelectrons in the four cells of the first
>> >> layer, the spectra you show looks strange: with your 23 pe/MeV
>> >> conversion
>> >> factor, the means of your downstream and upstream spectra are 34.25
>> and
>> >> 95.19 (respectively) that is significantly bigger values than we have
>> in
>> >> our report for 45 pe/MeV conversion for the sum of four cells of the
>> >> first
>> >> layer (24.56 and 55.81 respectively, see Figs.27 and 23 of
>> >> gluex-doc-1301
>> >> or the attachment to this e-mail). Because you used the ntuple that
>> were
>> >> produced by Irina, your numbers must be SMALLER than ours by the
>> factor
>> >> (23/45).
>> >>
>> >> Most probably, you used wrong variables from the ntuples. I did not
>> >> check
>> >> it, but you might have the same problem with your figures 10,11,12
>> also.
>> >>
>> >> Another issue is that for photoelectrons you can not just scale the
>> >> spectra is you use another MeV-to-pe conversion factor. Irina will
>> >> prepare
>> >> the correct figures for you tomorrow.
>> >>
>> >> Sorry,
>> >> Andrei
>> >>
>> >>
>> >>
>> >>
>> >> >
>> >> > Dear collaborators,
>> >> >
>> >> > I have uploaded a new version of the cover document, including a
>> >> summary.
>> >> > Please send me any feedback by noon JLab time, so I can place final
>> >> > documents on the web site for reviewers.
>> >> >
>> >> > Thanks, Elton.
>> >> >
>> >> > Elton Smith
>> >> > Jefferson Lab MS 12H5
>> >> > 12000 Jefferson Ave
>> >> > Suite # 16
>> >> > Newport News, VA 23606
>> >> > elton@jlab.org
>> >> > (757) 269-7625
>> >> > (757) 269-6331 fax
>> >> >
>> >>
>> >
>>
>>
>>
>>
>
>