sPHENIX is a new detector at RHIC.

[Rosi Reed <rjr215 AT lehigh.edu>]

Hello Everyone,

First, attached are two plots for single jet and dijet containment.
For the single jet containment, this is the number of jets a given jet
pT within the EMCal acceptance over all jets of that pT.  For the
dijet containment plot, this is versus the leading jet transverse
momentum so they are on the same scale.  This is the ratio of the
number of leading jets of a given pT where both the leading and
subleading jet are within the EMCal acceptance (and the subleading jet
has pt > 5) over the total number of leading jets with that momentum.
The sub-leading and lead jets are |delta phi| > 2.35, there is no
requirement that the sub leading jet be the highest pt sub-leading
jet.

I think this shows the statistical hit that we take with the reduced
emcal, as we are unlikely to analyze Calo jets that are not fully
contained within both the HCal and the EMcal.  The reason we would
want to do this is illustrated in Figure 1.5.

I can adjust these plots as needed up until about 4 pm today.

Line 91: I highly doubt we can improve upon the nominal configuration
using the reduced configuration with corrections ... the JES and JER
are both affected for the worse, and this means the correction and
unfolding will be more difficult.  In lines with what John has stated,
I don't think we want to make it too optimistic.

Regards,

Rosi



On Tue, Oct 24, 2017 at 12:26 AM, John Haggerty <haggerty AT bnl.gov> wrote:
> Gunther and Dave,
>
> Speaking as a high official of the project, it is good to see that the
> collaboration can agree on a plan to bring the costs within the boundaries
> the lab has asked.  As you know, I have looked into more radical changes
> without expending engineering effort on them, but I cannot see any better
> alternative to this proposal that could come anywhere near being ready in
> 202{1,2,3}
>
> Speaking as a member of the collaboration, I think we should try to convey
> more of a sense of loss and sacrifice.  Cutting the emcal acceptance in
> particular seems like a double whammy, because it not only cuts the
> acceptance, it makes the whole calorimeter system thinner, and I have even
> wondered whether the un-descoped detector is thick enough, and with the
> Inner HCAL probably gone, the fiducial region is pretty small.  Experiments
> often recover that region with endcap or end plug calorimeters, but I don't
> think that's a viable option for us, because it introduces a boundary which
> is inherently non-uniform.
>
> Another concern is the unknown unknowns we have introduced with the odd
> longitudinal segmentation in the calorimeters...  sure, there is now a lot
> of evidence that the signals look not so bad with this arrangement, but
> violating the conventional wisdom is often punished harshly by nature.  I
> don't know that we can say with certainty that the vast background ocean of
> low pt particles, jets, and slow secondaries which are now spinning around
> inside the magnet but outside the emcal do not have some very unfortunate
> effects.  I have not been able to put my finger on exactly what we should
> look for, but I think we have to keep looking for trouble.
>
> I know these are not very well formulated objections, and so may be
> impossible to take account, but I thought it might be useful to put them out
> there in case it inspires someone smarter than me to see more clearly where
> we might be going off the rails.
>
>
> On 10/21/17 12:02 AM, Gunther M Roland wrote:
>>
>>
>> Friends,
>>
>> As discussed at the General Meeting today, we are forwarding draft 1 of
>> our document outlining the detector scope for a $32M cost cap. The pdf file
>> can be found at
>> https://www.dropbox.com/s/5wyutbndogozm5q/sPH-GEN-2017-002_v1.pdf?dl=0
>> (we'll provide another link tomorrow for those that can't access dropbox)
>>
>> Please send your comments in reply to this mail, keeping the
>> [sPH-GEN-2017-002] tag in the subject line***. Comments received by
>> close-of-business on Monday, 10/23, will be most useful.
>>
>> Cheers,
>>
>> Gunther and Dave
>>
>> ***we will move future reviews to an sphenix-notes-l AT bnl.gov list, but the
>> list couldn't be generated in time for this note.
>> _______________________________________________
>> sPHENIX-l mailing list
>> sPHENIX-l AT lists.bnl.gov
>> https://lists.bnl.gov/mailman/listinfo/sphenix-l
>>
>
>
> --
> John Haggerty
> email: haggerty AT bnl.gov
> cell: 631 741 3358
>
> _______________________________________________
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> sPHENIX-l AT lists.bnl.gov
> https://lists.bnl.gov/mailman/listinfo/sphenix-l



-- 
Rosi Reed
Assistant Professor, Physics Department
Lehigh University
(610)758-3907
16 Memorial Drive East Office 406
Bethlehem, PA 18015

Attachment: DiJetContainment_NomvsRedEMCal_10242017.eps
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Attachment: SingleJetContainment_NomvsRedEMCal_10242017.eps
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