sPHENIX is a new detector at RHIC.

["Michael P. McCumber" <mccumber AT bnl.gov>]

sPHENIX simulations meeting minutes

05/03/2016

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All - Software updates

DST decode updates

+ more expected SIPM temperatures

Martin Temperature Class

+ needed to readout temperatures

+ 10-30 temperature readings per run

Macros: Cherekov channels

+ needed for test beam, reverses polarity on Cherekov

Macros: tracking up

+ some clean up on the silicon tracking option

TPC code base:

Mike will touch base with Alan later today

a HIJING TPC tune exists and we plan to update the coresoftware with that tune

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Dennis Perepelitsa: G4 B-jet Tagging

Slides: https://indico.bnl.gov/getFile.py/access?contribId=1&resId=0&materialId=slides&confId=1908

Porting science review code into GEANT4 studies

Uses the Track-Counting Method (reviews technique)

Sort tracks by DCA significance and cut

Light particle decays give tails from long-lived decays

Multiple particle cuts give more discriminating power

Rosi: What radius jets? R=0.4

Rosi & Mike: Discussion of b-jet vs c-jet physics at 20 GeV/c

Tabled for a later discussion

Diagnostic plots by PID of different event samples

Showing initial results from forcing b,c,light production

Mike: Cut off at 1mm in DCA an artifact of the tracking tune and can be pushed outward by trading CPU

Slide 16: DCA error shows sharp feature at 50 um. Not clear its origin, could be a bug. Will require follow up from experts. Could also be a feature of the 50um pixel size + a chisq cut.

Discussion of "shark fin" feature in GEANT4 on Slide 18

Take home: GEANT4 full sim still shows key features are preserved

Will follow up on the detailed features

Ready to start comparing tracking configs

Follow up on DCA error needed

Realistic l/c/b

Discussion of moving into HIJING studies

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Haiwang Yu - GenFit Updates

Slides: https://indico.bnl.gov/getFile.py/access?contribId=2&resId=0&materialId=slides&confId=1908

Refitting is working

Give similar results for cylinder geometries

Revertexing is not yet working

GFRave does not handle negative mag field well

Switching to default Rave to try to solve this problem

GFRave is the GenFit interface to Rave

Discussion of momentum resolution modeling

Focusing on vertexing code

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Sanghoon Lim - Short RAVE updates

Slides: https://indico.bnl.gov/getFile.py/access?contribId=3&resId=0&materialId=slides&confId=1908

Follow up with RAVE package, zero field assumption for now

Shows multivertexing capabilities of perfect MIE tracker

Two track vertexes merge at dz = 800 um (not surprising given the 425 um long pixels)

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Vera Loggins - sPHENIX software on real data: Test Beam EMCal Analysis

Slides: https://indico.bnl.gov/getFile.py/access?contribId=4&resId=0&materialId=slides&confId=1908

EMCAL-only data from Test Beam

Energy Scan data

Slide 2: Jin - Linearity errors seem too large.

top left panel distribution c1 for different energies (c1 == Cerenkov signal)

upper right panel energy distribution fit to a gaussian

Discussion of Cerenkov counter behavior (pressure, amplification)

Jin asks to overlay energy distribution before and after the Cerenkov cut

Using Cerenkov cuts to identify electrons

Slide 8: review of cuts used for id and background rejections, includes vetoes on leakage

Next steps: Needs to add hodoscope cuts and optimize

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Michael P. McCumber, PhD
Los Alamos National Laboratory
505-709-8161

On Mon, May 2, 2016 at 9:32 AM, Michael P. McCumber <mccumber AT bnl.gov> wrote:

Hello everyone,

This is a reminder that we will have a sPHENIX simulation and software meeting, Tue May 3rd, 1PM EST @ 2-219. I will be leading the discussions as Jin and Chris will be otherwise occupied.

Currently on agenda:

* Software updates 

* Simulation status for ALD charge

More contributions are welcomed too. 

The agenda page is at https://indico.bnl.gov/conferenceDisplay.py?confId=1908    , for which the common modification password is "1008"

*            For residents at BNL, we will meet at the 2-219 conference room this time

*            To join the Meeting via phone bridge:  https://bluejeans.com/619960505  

*            To join via Phone:

1) Dial:

        +1.408.740.7256

        +1.888.240.2560(US Toll Free)

        +1.408.317.9253(Alternate number)

        (see all numbers - http://bluejeans.com/numbers)

2) Enter Conference ID: 619960505

Mike

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Michael P. McCumber, PhD
Los Alamos National Laboratory
505-709-8161