FWD Software

[Akio Ogawa <akio AT bnl.gov>]

Hello

I'm seeing no code update and git pull says

   "Your branch is up to date with 'origin/dev'"

my origin is https://github.com/jdbrice/star-sw-1.

Waiting for readme to see which data one I should be looking at.

OGAWA, akio                 Email : akio AT bnl.gov
BrookHaven National Lab. Physics Dep. 510A 2-235
Upton, NY, 11973-5000          Tel. 631-344-5293

On Wed, 7 May 2025, "Brandenburg, Daniel" wrote:

> Hi All,
>
>  
>
> Please find several updates below. I would like to avoid meetings entirely 
> devoted to me reporting what I’ve
> done, so unless I hear of an update, please consider this email in place of a 
> meeting today. However, if
> there is anything to discuss I am more than happy to have a meeting.
>
>  
>
> PicoDst updates
>
>  *  PicoDst now has “FwdVertices” that contain a position, cov matrix, and 
> nTracks associated with the
>     vertex.
>  *  FwdTracks mVtxIndex is now split 6 bits vs. 2 bits to contain the track 
> type (2 bits) = [0=Global,
>     1=Beam line Constrained, 2=Primary Vertex constrained, 3=FWD vertex 
> constrained] and the 6 bits provide
>     the index of the vertex depending on the type.
>  *  mGlobalTrackIndex should now be set correctly in the PicoDst. For 
> Beam-line, primary, or FWD vertex
>     constrained tracks it is the corresponding global track index (in 
> FwdTracks array), for Global tracks it
>     is set to UShort_Max
>
>  
>
> Tracking Performance:
>
>  *  There has been some confusion about the p_z=10 etc. However, I have 
> investigate both mathematically and
>     via pythia/single particles. If we have ONLY FST measurements + PV, we 
> have essentially no
>     measurement/constraint of the track sagitta. The fits are conducted with 
> q/p_T and angular variables,
>     but if the sagitta is not constrained it means that we only measure (to 
> first order) a ratio between pT
>     and pZ within a significant range.
>  *  It would be nice for someone else to verify this with single particle or 
> pythia -> compare track refit
>     ON/OFF to see what happens when FST+sTGC vs. FST only.
>  *  To this end I started working (again, since we started this last year) to 
> investigate the viability of
>     utilizing EPD hits into tracking.
>  *  Unfortunately EPD was somehow not included in our recent productions (Not 
> available in MuDst) – I am
>     trying to see if this can be recovered or if a new production would be 
> needed – I am trying to determine
>     BEFORE initiating the production file reconstruction request
>
>  
>
> sTGC:
>
>  *  Sam (OSU) produced a version of the sTGC reconstruction code that 
> provides cluster level information to
>     the FWD Tracking – instead of combining into spacepoints.
>  *  Since each sTGC has potentially 4 measurement layers, this should greatly 
> improve the chance of having
>     at least one valid sTGC measurement along a tracks trajectory  - which 
> greatly improves the sagitta
>     measurement and therefore the pT/pZ constraints as discussed above.
>  *  This is partially integrated and I will give further updates on its 
> progress.
>
> Misalignment:
>
>  *  I found the (or at least a) major error in the misalignment that was 
> applying the rotations twice
>     causing the hits final position to be badly distorted.
>  *  With this fixed the misalignment-enabled tracking is much more consistent 
> with the previous “spacepoint”
>     mode.
>  *  With this I am ready to try with/without survey tables applied.
>
>  
>
> Productions:
>
>  *  Due to the uncertainty related to the EPD information, I have not 
> requested a production run from Gene,
>     but I will try to close the loop on this today.
>  *  I have groups of ~30M events running. In each folder I am putting a 
> README file with description of any
>     important details – e.g. FST ONLY, or misalignment mode ON, etc.
>
>  
>
> Tasks that could use help:
>
>  *  Update StFwdTrackMatchMaker to use (R, phi) instead of (X,Y) for distance 
> matching
>  *  Plots showing correlations between mid-rapidity detectors (TPC tracks, 
> TOF, BEMC, etc.) and FWD
>  *  Plots showing correlations between EPD or EEMC and FWD
>  *  Plots comparing FWD vertex positions with Event Vertex positions
>  *  Summary of event stats vs. triggers (# of FST hits, # of tracks, FCS 
> info) – I currently process all
>     events regardless of triggers.
>  *  Summary showing availability of vertex information(vs. trigger) – TPC, 
> VPD, EPD, ZDC, BTOF…
>  *  Just to name a few ?
>
>  
>
>  
>
> Best,
>
> Daniel Brandenburg
>
> Assistant Professor
>
> College of Arts and Sciences
>
> Department of Physics
>
> Ohio State University
>
>  
>
>