sPHENIX discussion of software

["Huang, Jin" <jhuang AT bnl.gov>]

Also available on agenda page: https://indico.bnl.gov/conferenceDisplay.py?confId=1780

 

Software updates:

Many updates on GitHub repository recently as linked to the agenda.

 

Action Item: requested Dennis to help crosscheck Nils’ pull requests on pythia6->HEPMC implementation,

·       https://github.com/sPHENIX-Collaboration/coresoftware/pull/115

·       https://github.com/sPHENIX-Collaboration/macros/pull/14

 

Upcoming updates:

·       Chris: suggest split event generator macro from main to separated file as it gets larger. We plan to do so after merging Nils’ requests.

·       Chris: Layer ID was mixed with detector ID in indexing G4Hit in its storage. Investigating why it has not yet broken some code. May lead to changes in hit storage.

 

 

Update on Generic Kalman Filter: Haiwang Yu

 

New strategy: switch to use the internal track presentation (RKTrackRep) in GenFit2 with several advantages:

1.       No need to bother with Geant3/4 in Kalman fit part

2.       Existing code, and used in many collaboration

Many work done:

·       Verified multiple scattering estimation with own back of envelope calculation

·       Verified track fit works with Z-plane silicon detectors with pull tests

Plan on test with cylindrical trackers and compare with the stock sPHENIX track fitter.  

 

Action Item [Chris]: work with Abhisek Sen on implementing Geant4 -> TGeo geometry export as a standard feature for sPHENIX simulation

 

 

Update on calorimeter prototype simulation: Chris/Murad/Jin

 

EMCal prototype preview:

https://github.com/sPHENIX-Collaboration/coresoftware/pull/121

 

John H.: it is very useful to simulate for day-one data, tower-by-tower energy for 120 GeV proton. Beam size and angular divergence should be small.

 

Sarah: where the lower side tail in energy response comes from?  

Jin: expect from leakage. Varying sampling fraction VS depth could play a role too. Need to be studied.

  

Chris: is there a tower and scintillator mapping definition?

John H./Megan: doc DB map tower to tower ID for tower definition. Each five tiles are tied to a tower.

 

 

Fast calorimeter simulation: Ron Belmont

 

Page 3:

Ron: fast simulation used single layer 0.1x0.1 towering, like both HCal

 

Page 5:

Jin: it is interesting that the histogram is very Gauss, good to cross check single tower energy from sPHENIX full simulation

Gabor: as each entry is averaged over all tower in one event, therefore central limit theorem bring the biased high tail distribution to a nice Gauss.

 

Page 6:

Chong: What is open circle?

Ron: Without calorimeter.

 

Sarah: Why dip around medium pT range?

Jin/Mike: hypothesis is at low pT the tracking purity is good and at high pT the calorimeter purity works well. Somewhere in the middle both methods lack strength leaving a purity gap.

Mike/Ron: the low tracking purity only comes from ganging strip output channels. Do not expect it in full MAPS tracker too. Although it could affect MAPS+strip (ganged)

 

Ron: Memory issues when running full Hijing simulation in fast tracking

Chris: High memory condor slots are available by restrict 2 such job per machine. Limited number of slots (300-500 condor slots) is available cross PHENIX RCF facility. Other than these slots, the nominal memory limit is 2GB. People are welcome to use these slots as study needs. Documentation to come.

Mike: from previous experience, one can reduce memory usage by reducing the track phase space, e.g. cut on pT>3GeV in tracking code for specialized studies.

 

 

______________________________

 

Jin HUANG

 

Brookhaven National Laboratory

Physics Department, Bldg 510 C

Upton, NY 11973-5000

 

Office: 631-344-5898

Cell:   757-604-9946

______________________________

 

 

> -----Original Message-----

> From: Huang, Jin

> Sent: Monday, March 21, 2016 1:24 PM

> To: 'sphenix-l AT lists.bnl.gov' <sphenix-l AT lists.bnl.gov>; 'sphenix-software-

> l AT lists.bnl.gov' <sphenix-software-l AT lists.bnl.gov>

> Subject: [reminder] sPHENIX simulation and software meeting, Tue Mar 22,

> 1PM EST @ 2-219

>

> Dear All,

>

> This is a reminder that we will have a regular sPHENIX simulation and

> software meeting, Tue Mar 22, 1PM EST @ 2-219.

>

> Currently on agenda: tracking update on the generic Kalman filter, and

> calorimetry update on the prototype simulations. More contributions are

> welcomed too.

>

> The agenda page is at

> https://indico.bnl.gov/conferenceDisplay.py?confId=1780 , 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

>

> Cheers,

>

> Jin

>

>

> ______________________________

>

> Jin HUANG

>

> Brookhaven National Laboratory

> Physics Department, Bldg 510 C

> Upton, NY 11973-5000

>

> Office: 631-344-5898

> Cell:   757-604-9946

> ______________________________