sPHENIX is a new detector at RHIC.

[John Haggerty <haggerty AT bnl.gov>]

Tony and all,

I would add to Ed's remark that I think a narrative where we explain 
that we have a v1 design of a tracking system already, and it gives us 
90 MeV mass resolution in p+p, and degrades as we go to the most central 
Au+Au because we are learning how to better simulate and test our actual 
detector configuration but we're studying how to improve it as we evolve 
from CD-1 to CD-2 sounds pretty reasonable to me.

On 5/7/18 12:10 AM, Edward O'Brien wrote:
>      Hi Tony,
>       I believe I answered your question during the General Meeting, but
>      let me put it into an e-mail so that we have a record. We will
>      include a table of UPP's in the Preliminary Project Execution Plan. 
> DOE and
>      BNL Management will sign this document, but it is considered a 
> preliminary
>      document. The PEP that we will write 1 year from now for the CD-2 
> review
>      will be binding, but not the preliminary PEP. So we have some 
> wiggle room today.
>      What would be bad, and what happened at the Director's review, 
> would be if we
>      were to include numbers into the UPP table that appears in the 
> PPEP, and
>      then have presentations at the OPA review that contradict these 
> numbers. We should
>       settle this week on the Upsilon (1S) mass resolution value that 
> will be presented at the
>      upcoming review, and make sure that the same number is used in all 
> documents.
>      I expect that the number will only appear in the PPEP, and the 
> presentations by you
>      and Gunther.
>
>      Ed
>
> On 5/1/18 8:34 PM, Anthony Frawley wrote:
> > Hello Gunther,
> >
> >
> > I attach some plots for the Y(1S) mass resolution. All are without the 
> > MVTX, and with 50 ns SAMPA chip peaking time.
> >
> >
> > The first is for low occupancy events (mass resolution 86 MeV). This 
> > is the ultimate resolution limit
> >
> >
> > The second is for the Y(1S) embedded in central Hijing (0-4 fm). This 
> > shows what we expect at present for the mass resolution for central 
> > events integrated over a store.
> >
> >
> > The mass resolution for single central Hijing with no pileup is 106 
> > MeV. That is not a realistic scenario.
> >
> >
> > Question for Ed: If we cannot meet the 100 MeV UPP with the existing 
> > clustering, is that a problem for this review?
> >
> >
> > Thanks
> >
> > Tony
> >
> >
> > ------------------------------------------------------------------------
> > *From:* Gunther M Roland <rolandg AT mit.edu>
> > *Sent:* Friday, April 27, 2018 9:39 AM
> > *To:* jhuang AT bnl.gov; Perepelitsa, Dennis; Rosi Reed; 
> > lajoie AT iastate.edu; O'Brien, Edward; Haggerty, John; Glenn Young; 
> > Anthony Frawley; Morrison, David
> > *Cc:* sphenix-l AT lists.bnl.gov
> > *Subject:* UPP questions
> >
> >
> > Friends,,
> >
> > Maria just reminded us that we will have a dry-run of the CD-1 review 
> > plenary talks next Wednesday. I am not sure we will quite have the 
> > final plots at that time, but we need to figure out what the line of 
> > argument is going to be.
> >
> > We have a nice set of new simulations for the MIE configuration for 
> > e.g. jet energy resolution and various physics plots. I'm now thinking 
> > of how to make the connection to the UPPs for the OPA talk, and I'm 
> > finding that not so easy.
> >
> > As an example, the Jet resolution UPP in my notes is "Jet resolution 
> > of < 150%/sqrt(E)" (did we specify at which E, as the resolution does 
> > not go as sqrt(E), but has a constant term from the AuAu underlying 
> > event?). Our simulations however show a resolution that is much better 
> > than that. E.g. 15% at 50GeV from simulations vs 150%/sqrt(50) = 21% 
> > from the UPP.
> >
> > So, my questions/suggestions:
> > - I assume it is ok if the UPP is somewhat relaxed compared to the 
> > performance in simulations?
> > - We probably should add a line on the performance plots reflecting 
> > the UPP performance
> > - We should add a set of points corresponding to the UPP performance 
> > to the physics plots
> > - for the physics plots, one needs some to provide some scale of why 
> > we want to reach a certain performance. I'm planning to argue that we 
> > want comparable performance to that at LHC (e.g. gamma-jet balance 
> > uncertainties, Upsilon resolution). Any better ideas?
> > - for the t-shirt plot, it would be nice to have for comparison also 
> > the current RHIC status (applies only to jets/hadron RAA) and a backup 
> > plot of how much the MIE vs reference acceptance costs us
> >
> > Question to Dennis/Rosi: Any chance of getting a photon resolution 
> > plot from simulation to compare to the photon UPP of <15%/sqrt(E) 
> > photon resolution? I think it would be good to fold this into the 
> > physics plot.
> >
> > Question to Tony: Where can I find the latest Upsilon mass plot for 
> > pp? The UPP (Y(1s) mass resolution < 100MeV) probably needs to refer 
> > not just to the system, but also specific running conditions: single 
> > central Au+Auevent, max pileup, average pileup? It would be good to 
> > have a comparison of the resolution for pp, single central Au+Au and 
> > central Au+Au at max pileup (beginning of store) to see where we stand.
> >
> > Cheers,
> >
> > Gunther


--
John Haggerty
email: haggerty AT bnl.gov
cell: 631 741 3358