FTPC

 

 

Welcome to the FTPC Homepage

First FTPC Event
First FTPC Event

Detector Operation - all information necessary to operate FTPCs

Data Quality Assurance

Pad Monitor

Calibrations

Documentation

Software

Hardware

DAQ

InterlockSystem

SlowControl

 

 

 

DAQ

FTPC DAQ

The FTPC data aquisition system is tied in with the main STAR DAQ. From the receivers onward, all hardware components are identical. The software for the electronics channel mapping is committed to the STAR cvs repository $CVSROOT/online/ftpc/MapFtpcElectronicsToDaq

 

The signals from the FTPC electronics are sent to DAQ where each 
readout board,mezzanine card,asic is mapped to an FTPC sector,daqrow,daqpad.

HARDWARE:

2 identical FTPCs - Ftpc West = 1, Ftpc East = 2
5 rings/FTPC
2 padrows/ring
10 padrows/FTPC
6 sectors/padrow
6 sectors/padrow x 10 padrows/FTPC = 60 hardware sectors/FTPC
160 pads/sector
9600 pads/padrow
= 19200 electronics channels for both FTPCs

ELECTRONICS:
20 readout boards (RDOs)
10 RDOs/FTPC
3 mezzanine cards/RDO
= 3 mezzaanine cards/RDO x 10 RDOs/FTPC = 30 electronic sectors/FTPC

DAQ:
The signals from the FTPC electronics are mapped to the hardware with the FTPC_PADKEY.h file.

DAQ notation:
30 daqsectors/FTPC (Ftpc West 1-30, FtpcEast 31-60)
2 daqrows/daqsector
320 daqpads/daqsector = 2 x 160 daqpads/daqrow

Ftpc Ring Padrow Sector daqrow daqpads
1 1 1,2 1,7 1,2 1-160
2,8 1,2 161-320
3,9 1,2 321-480
4,10 1,2 481-640
5,11 1,2 641-800
6,12 1,2 801-960
2 3,4 13,19 1,2 1-160
14,20 1,2 161-320
15,21 1,2 321-480
16,22 1,2 481-640
17,23 1,2 641-800
18,24 1,2 801-960
3 5,6 25,31 1,2 1-160
26,32 1,2 161-320
27,33 1,2 321-480
28,34 1,2 481-640
29,35 1,2 641-800
30,36 1,2 801-960
4 7,8 37,43 1,2 1-160
38,44 1,2 161-320
39,45 1,2 321-480
40,46 1,2 481-640
41,47 1,2 641-800
42,48 1,2 801-960
5 9,10 49,55 1,2 1-160
50,56 1,2 161-320
51,57 1,2 321-480
52,58 1,2 481-640
53,59 1,2 641-800
54,60 1,2 801-960
2 1 1,2 6,12 1,2 1-160
5,11 1,2 161-320
4,10 1,2 321-480
3,9 1,2 481-640
2,8 1,2 641-800
1,7 1,2 801-960
2 3,4 18,24 1,2 1-160
17,23 1,2 161-320
16,22 1,2 321-480
15,21 1,2 481-640
14,20 1,2 641-800
13,19 1,2 801-960
3 5,6 30,36 1,2 1-160
29,35 1,2 161-320
28,34 1,2 321-480
27,33 1,2 481-640
26,32 1,2 641-800
35,31 1,2 801-960
4 7,8 42,48 1,2 1-160
41,47 1,2 161-320
40,46 1,2 321-480
39,45 1,2 481-640
38,44 1,2 641-800
37,43 1,2 801-960
5 9,10 54,60 1,2 1-160
53,59 1,2 161-320
52,58 1,2 321-480
51,57 1,2 481-640
50,56 1,2 641-800
49,55 1,2 801-960


Data Quality Assurance


FTPC Data Quality Assurance and Quality Control

   During data taking it is very important to monitor the quality of the data being taken. This should be done at least once a day and whenever the FTPC has been turned back on.

  •   Online histograms - "Panitkin Plots"
  •   FTPC Fast Offline QA histograms 
  •   FTPC temperature readings - check if the FTPC temperature readings are in the Slow Control Archive. There should be readings for both Ftpc body (West 6 readings, East 6 readings) and Ftpc extra (West 6 readings, East 7 readings) temperatures. It is especially important to check these after the FEEs have been turned off; there is a non-negligible possibility that the body temperature readings for FTPC East do not come up again. If this is the case, call an expert.

 

 

 

 

 

 

Fast Offline QA Histograms

FTPC Fast Offline Histograms

 

 

Online histograms - "Panitkin Plots"

 

During a run, online histograms are collected for each sub-system. The online histograms give the first indication of detector hardware problems. Therefore it is extremely important to check these histograms in the control room on evp.starp.bnl.gov at the end of each run. They should also be saved so that they are available for future viewing via the RunLog Browser.

A histogram description has 9 arguments:
1 for 1-D, 2 for 2-D histo
histogram name
histogram title
number of bins x-axis
lower bound x-axis
upper bound x-axis
0 for 1-D histos, number of bins y-axis for 2-D histos
0 for 1-D histos, lower bound y-axis for 2-D histos
0 for 1-D histos, upper bound y-axis for 2-D histos

The following histograms are collected for the FTPC (they are on pages 25-27 up until January 3, 2008 when BEMC histograms were added. The FTPC histograms moved to pages 30-32 starting with run 9003070):

Please inform the FTPC group if you observe large scale changes in any of the FTPC histograms.
The plots on page numbers 26 and 27/ pages 31 and 32 starting with run 9003070 are the most important. They must be checked for every run.

Currently the sample histograms shown below are for the dAu 2007 Run 8340066
  • page 6  FTPC event size on a log10 scale
                Contains the event size histograms for TPC, BEMC, FTPC, L3, SVT and TOF
                Args: 1,h11_ftp_evsize,log of FTPC Buffer Size,50,0.,10.,0,0,0

  •  
  • page 7  FTPC fraction of total event in %
                Contains the event size fraction histograms for TPC, BEMC, FTPC, L3, SVT and TOF
                Args: 1,h105_ftp_frac,FTP Event Size Fraction (%),50,0.,100.,0,0,0

  •  
  • page 8  FTPC event size on a log10 scale for the last 2 minutes
                Contains the event size vs time histograms for the TPC and FTPC
                Args: 2,h337_ftp_time_size_2min,FTPC Event Size vs time(sec),600,0.,600.,80,0.,8.

  •  
  • page 25/page 30:
                 % of FTPC occupied channels
                Args: 1,h49_ftp,FTPC Occupancy (in %),100,0.,100.,0,0,0

                FTPC event size on a log10 scale
                Args: 1,h11_ftp_evsize,log of FTPC Buffer Size,50,0.,10.,0,0,0

                 % of FTPC occupied channels for laser runs
                Args: 1,h51_ftp_OccLaser,FTPC Occupancy (in %) Lasers,100,0.,100.,0,0,0

                 Total charge in FTPC on log10 scale
                Args: 1,h48_ftp,log of Total FTPC Charge,30,0.,6.,0,0,0

                 % of FTPC occupied channels for pulser runs
                Args: 1,h50_ftp_OccPulser,FTPC Occupancy (in %) Pulsers,100,0.,100.,0,0,0
  • page 26/page 31FTPC chargestep histograms
                Args: 1,h109_ftp_west_time,FTPC West timebins,256,-0.5,255.5,0,0,0
                Args: 1,h110_ftp_east_time,FTPC East timebins,256,-0.5,255.5,0,0,0

                The chargestep corresponds to the maximum drift time in the FTPC (clusters from inner radius
                electrode) and is located near 170 timebins. This position will change slightly with atmospheric
                pressure. The other features of these plots are due to electronic noise and pile-up background.


                If there is no step visible near 170, something is wrong. Please contact an FTPC expert.

  • page 27/page 32:
                Args: 2,h338_ftp_west,FTPC West pad charge: pad vs row,10,0.,10.,960,0.,960.
                Args: 2,h339_ftp_east,FTPC East pad charge: pad vs row,10,0.,10.,960,0.,960.

                Red areas = hot FTPC electronics
                White areas = dead FTPC electronics

                Always check these 2 plots in the first run after an FTPC trip. If new red or white areas show up,
                first check the FTPC anode voltages. If the anode voltage readings are correct, please contact
                an FTPC expert.


                On December 17, 2007, Alexei masked out RDO 10 East. On page 27/32 RDO 10 East is now a white area.

 

 

Slow Control Archive

FTPC Slow Control Archives

 

 

 

 

Detector Operation

 

   FTPC expert(s) currently on call:

   Alexei Lebedev           alebedev@bnl.gov         Phone: 3101         Cell phone: 631 255 4977

 

TO ALL DETECTOR OPERATORS:

Please remember to place the FTPC into "Physics" mode and verify anode voltages (1800 W, 1800 E) after taking pedestals.

In case of an FTPC alarm,please check the "Temperature-Pressure" window - if ALL readings in FTPC East and/or West = 0, call Alexei.

In case of an anode trip, please enter the time the trip occurred and which FTPC and sector tripped into the FTPC log book.

Y2004 Standard set points

    Detector always ON
    Change configuration to operate in different modes or to set the detector to rest waiting for beam
    Set the system in ``Magnet ramp'' configuration ONLY when the magnet is ramping

ALWAYS!!!!!! verify Anode Voltages = voltages for selected run mode !!!


Voltage Settings
Cathode voltage (2 channels)     -10kV±5V 
Anode voltage (2x6 channels), Physics    +1800V ±2V West, +1800V ±2V East
Anode voltage (2x6 channels), laser    +1200V±2V West, +1200V±2V East
Anode voltage (2x6 channels), pedestals    +1000V±2V West, +1000V±2V East
Anode voltage (2x6 channels), stand by   0V West/East, (+~15V are displayed) 
Gating grid (2x4 channels)  -76V±2V open, -76V±115V closed

 



Y2007/2008 Standard Values
Water pressure in (West/East)     -400mbar -> -100mbar 
Water temperature (West/East)     <31 C 
   
O2(ppm) (West/East)     <10ppm
H2O (dp C) Westt/East)     <-50 C dp
Ar flow = CO2 flow (West/East)     72l/h->78l/h; West=East 
   
Cathode current 0.14mA 
Anode current  -15nA < I < 15nA 

 

 

 

For more information, please consult:

* FTPC Operations Manual


* FTPC Shift Checklist


* FTPC Run School

 

 

 

 

InterlockSystem

From this page it is possible to read or download (in form of a 3 pages postscript file) the FTPC interlock document.

Last update 9/2/2000 by Gaspare Lo Curto

 

 

Pad Monitor

FTPC Pad Monitor

  

The pad monitor we use was developed by Andreas Schuettauf. It is referred to as the Munich Pad Monitor. (The FTPC pad monitor development was started by Jennifer Klay in Davis. Her documentation contains alot of useful information. Unfortunately, Jennifer left STAR before she finished the pad monitor.)

 

 

documentation

FTPC PadMonitor Project

Welcome! You have found the webpage dedicated to providing information and documentation on the FTPC PadMonitor. The FTPCs (Forward Time Projection Chamber) are a key sub-system of the STAR Experiment at RHIC. The PadMonitor is a software program designed to allow for monitoring of FTPC performance. The program can be separated into two basic parts: the GUI (Graphical User Interface) and the data I/O interface. The GUI has been designed using Java with the data I/O interface provided by the Java Native Interface to C and C++ code. This choice of languages reflects the desire to marry cross-platform transportability with legacy code already written for STAR DAQ data. In addition, we hope to be able to run the PadMonitor as a Servlet or Javascript from the Web, allowing collaborators access to view detector performance or issue trigger commands from a distance.


 

The following pages provide code, a description of the code and its development, and links to useful sites, as well as information about the STAR data acquisition and the FTPC prospective raw data format.

 

  • Raw Data Format This page provides background on the STAR DAQ Raw Data Format and the proposed FTPC version of the DAQ RDF.
  • FTPC PadMonitor Code Information includes a Java Class Library description, links to STAR DAQ Documentation and an explanation of Herb Ward's "Mock Data" writer code.
  • Source Code The most recent updates of the code can be found here. Please note that DAQ Format Reader code may be modified and older than what is available from the STAR CVS Repository.
  • Current Status/Immediate Future Informational page; also contains screenshots of the current program.
  • Links Various resources for this project as well as links to STAR information may be found here.
  •  

    Raw Data Format

    STAR DAQ Links

    STAR DAQ Home Page This is the local working home page for the DAQ Group. Specific links of interest on this site include:

  • Software Documentation This page contains the Format Reader Specification for the DAQ RDF Format Reader written by M. Levine, M. Schulz and J. Landgraf as well as other DAQ documentation.
  • Raw Data Format Document describes the structure of data files written out by DAQ. Information in this document details the general pointer structure and the specific pointer structure for the main TPC. Space has been provided to include documentation from sub-system groups.


  •  

    FTPC Raw Data Format

    The FTPC data format resembles that of the main TPC in many ways. Both systems utilize the same basic readout electronics, however certain physical differences between the two detectors call for different handling. These differences are outlined here:

    Main TPC

    24 Sectors-each one handled by a single VME crate
    Each VME crate contains 6 receiver boards and one "Sector Broker" (to handle global sector characteristics and communication)
    Each receiver board contains 3 mezzanine boards which buffer the data and host the STAR Cluster Finding ASICs (pedestal subtraction,gain correction, 10bit->8bit data conversion, 2D cluster finding)

    To reconstruct a single sector's data, one must gather:
    From each of six receiver boards, the contributions from all three mezzanine boards

    24 sectors in the main TPC
    384 pads per sector
    45 padrows per sector
    Number of pads per padrow variable (due to wedge-shape of sectors)
    512 timebins per pad

    Forward TPCs

    2 Chambers-each one handled by a single VME Crate
    Each crate contains 10 receiver boards and one "Chamber Broker" (performs the same functions as the Sector Broker but for a single FTPC Chamber)
    Each receiver board handles three FTPC Sectors (30 sectors per chamber)
    Each receiver board has 3 mezzanine boards. The simplest sector->mezzanine mapping is 1:1, but may not necessarily be so. In order to be general, the pointer structure is set up such that from the receiver board, one points to a sector and from the sector one points to the mezzanine board.

    To reconstruct a single sector's data, one must gather:
    From one receiver board, the sector via contribution from one mezzanine board

    2 chambers in the FTPC sub-system
    30 sectors per chamber
    320 pads per sector
    2 padrows per sector
    160 pads per padrow
    512 timebins per pad

    Ideally, one would like to hide this heirarchy behind a simpler user interface. This has been done by making the FTPC Format Reader very similar to the main TPC. Users request data from a specific sector, numbered 1 to 60 (1-30 for West FTPC, 31-60 for East FTPC). The user numbering scheme follows the FTPC Cabling design drawings. The mapping to correct receiver board and mezzanine contributions for a given sector is provided by a header file included with the Format Reader.

    FTPC Raw Data Format Document (postscript)


    DAQ/Data Schematics

    View some schematic pictures of the DAQ design and the current Raw Data Format:

  • Schematic of DAQ Design
  • Schematic of Data Format


  • The following is a diagramatical sketch of the information path explained in the DAQ Raw Data Format Document.

  • STAR Data Model...1
  • STAR Data Model...2
  • STAR Data Model...3
  • STAR Data Model...4
  • STAR Data Model...5
  • STAR Data Model...6
  •  

    SlowControl

     

    FTPC Slow Control

     

     

     

    Software

     

    FTPC Software

    • Overview of the FTPC software
    • List of the FTPC software location and contact people

    Calibration Software

    Simulation and Reconstruction Software

    •  SEE FTPC in ITTF for information on Maria Mora's integration of the FTPC into ITTF

     

    How to

     

     

     

     

     

     

     

     

     

     

     

     

    List

     

    Group

    Task Description/Problems

    Location of Source Code

    Contact

    DAQ

     

     

     

     

    Map FTPC electonics to DAQ

    $CVSROOT/online/ftpc/MapFtpcElectronicsToDaq

    Janet

     

    FTPC "gain table" for DAQ

     

    Frank

    Online

     

     

     

     

    FTPC Detector Control
         Documentation
         Interactive control panels running under
         ftpccrew@cassini.starp

    /afs/rhic.bnl.gov/star/doc_public/www/ftpc/Operations

    Terry

     

    Slow Control

     

    Terry

     

    FTPC Slow Control Monitoring Facility
    Plots and lists contents of slow control archives
    (On January 23 the FTPC Y2004 slow control archive was split into 2 parts.)

     

    Terry

     

    Pad Monitor

    $CVSROOT/online/ftpc/FtpcPadMonitor

    Janet

     

    Online Tools:
         1) Event Pool Reader - read and histogram events from /evp
         2) FTPC Display - evp event->*.ps file which contains 2-D
             pad vs. timebin plots and 3-D plots of deposited charge
         3) Noise Finder - evp event -> *.ps file which shows dead
             and/or noisy pads (see page 23 !!)

     

    Terry

    Janet

     

    Online histograms ("Panitkin plots")

     

    Janet

    Drift Velocity Monitor

    OBSOLETE

     

     

     

    LabView program running on bond.starp

     

     

     

    bond.starp -> virgo.starp samba connection

     

     

     

    virgo.starp cron job - copies files from /DV2/Today to /DV2/Store

     

     

     

    Conversion of DVM data files to root format

     

     

     

    StFtpcDVMMaker - DVM data analysis programs

    $CVSROOT/offline/StFtpcDVMMaker

     

    Calibration

     

     

     

     

    Noise Finder:
         GetGain,FindNoise,WriteAmpSlope

     

    Terry

     

    Drift Maps:
         Magboltz1

     

     

         Magboltz2

     

     

    $CVSROOT/StRoot/StFtpcDriftMapMaker
    $CVSROOT/StRoot/macros/examples/FtpcDriftMapMaker.C

    $CVSROOT/online/ftpc/Magboltz2

    Janet

     

    Laser Analysis:
         1) Convert st_laser*.daq files to *.root files
         2) StFtpcLaserMaker

     

    Terry

    Databases

     

     

     

     

    Slow Control -> Online database -> Offline database

     

    Terry

     

    Offline database:
         Geometry_ftpc/
                                   ftpcAsicMap
                                   ftpcClusterGeometry
                                   ftpcDimensions
                                   ftpcInnerCathode
                                   ftpcPadrowZ
         Calibrations_ftpc/
                                   ftpcAmpOffset
                                   ftpcAmpSlope
                                   ftpcCoordTrans
                                   ftpcDeflection
                                   ftpcDriftField
                                   ftpcEField
                                   ftpcElectronics
                                   ftpcGas
                                   ftpcGasOut
                                   ftpcGasSystem
                                   ftpcTimeOffset
                                   ftpcVDrift
                                   ftpcVoltage
                                   ftpcdDeflectiondP
                                   ftpcdVDriftdP

     

    Terry

     

    StDb/idl - idl definition files for FTPC database tables

    $CVSROOT/StDb/idl

    Janet

    Simulation/ Reconstruction

     

     

     

     

    StFtpcSlowSimMaker

    $CVSROOT/StRoot/StFtpcSlowSimMaker

    Frank

     

    StFtpcClusterMaker

    $CVSROOT/StRoot/StFtpcClusterMaker

    Joern

     

    StFtpcTrackMaker

    $CVSROOT/StRoot/StFtpcTrackMaker

    Markus

     

    pams/ftpc/idl
         FTPC idl files used in FTPC Slow Simulator

    $CVSROOT/pams/ftpc/idl

    Janet

    QA

     

     

     

     

    St_QA_Maker

    $CVSROOT/StRoot/St_QA_Maker

    Gene

    Janet

    Embedding

     

     

     

     

    StFtpcMixerMaker

    $CVSROOT/StRoot/StFtpcMixerMaker

    Frank

    Analysis

     

     

     

     

    StFtpcMcAnalysisMaker
         creates the NTuples used for efficiency, momentum
         resolution and so on by a wide variety of tools.
         (Code works but not yet ready to pass a CVS code
         review)

     

    Frank

    ITTF

     

     

     

     

    StiFtpc

    $CVSROOT/StRoot/StiFtpc

    Maria Mora-Corall

    Documentation

     

     

     

     

    Web pages

    /afs/rhic.bnl.gov/star/doc_public/www/ftpc
    /afs/rhic.bnl.gov/star/doc_private/www/ftpc

    Janet

     
    This page was written by Janet Seyboth on Febuary 10, 2004

     

     

    Online

     

    FTPC "Online" Calibration Software

    The FTPC "online" calibration software is a collection of programs and macros which run on the FTPC
    online machines (virgo-run09.starp,cassini-run09.starp) processing either data directly from the event pool or from
    a *.daq file.


    All the FTPC calibration software is committed to the online/ftpc branch of the STAR CVS reposititory.
    Each committed module contains a README file and a doc subdirectory which contain all the pertinent
    information regarding the purpose and use of the program and/or macros contained in the module.

    The FTPC "online" calibration program library is located on virgo-run09.starp in /data/FtpcOnlineLibrary
    and can be used from the ftpccrew account on virgo-run09.starp.



    Attention: The FTPC 3-D display software does not run with ROOT_LEVEL 4.04.02


                                                          Programs in the FtpcOnlineLibrary
    Calib_Tool:
                         
    calib_tool creates a graphical user interface which allows the user to interactively analyze
                          the *.root files produced when the daq files from an FTPC laser run are processed
                         with the FTPC "private chain". The FTPC "private chain" produces a special output
                         file when DEBUGFILE is defined in StFtpcClusterMaker and StFtpcTrackMaker.

    CardFinder:
                        The
    CardFinder utilities,PadAnalysisCreate and PadAnalysisWrite, analyze the pads, locate
                        the bad and/or noisy chips and produce lists of the bad electronics.

    EvpPoolReader:
                         Reads, processes and displays event(s) from the event pool: /evp/a, /evp/b or
                         the "live" stream (the event which is currently being input into the event pool).
                         Due to firewall restrictions you can only access the event pool and the live stream from the  starp sub-net .
                        Click
    here for running instructions.
    FtpcPadMonitor:
                       
    padmon is a software program designed for monitoring the FTPC hardware performance.

    NoiseFinder:
                      
    NoiseFinder contains the programs and macros which produce the FTPC online and offline
                      gain tables.
                     Run the NoiseFinder programs GetGain and FindNoise from the FtpcOnlineLibrary
                     on virgo.starp.bnl.gov to create a gain table. The gain table flags out dead
                     and/or noisy pads. The NoiseFinder utility, WriteAmpSlope_cc.so, converts the
                     gain table into an ftpcAmpSlope.C file which is added to the offline data base
                     in the Calibrations_ftpc/ftpcAmpSlope table.

    Online_Tool:
                     Online_Tool contains the shell script ftpc_display and the L3 display
                     macros. The ftpc_display shell script provides an interface to FTPC online
                     event processing. An event from the event pool or from a daq file is read in
                    and the cluster finding and tracking results are displayed with the 3-D viewer.
                    Click
    here for running instructions.

     

    calib_tool

    FTPC Calib_Tool

    calib_tool creates a graphical user interface which allows the user to interactively analyze
    the *.root files produced when the daq files from an FTPC laser run are processed with
    the FTPC "private chain"
               "ftpc db globT detDb tpcDb dbutil in dst event"

    The FTPC "private chain" produces a special output file when DEBUGFILE is defined in
    StFtpcClusterMaker and StFtpcTrackMaker.

    For information on calib_tool, type

         calib_tool -h

    Which will print the following

    Usage: calib_tool [-l] [-b] [-n] [-q] [dir] [file1.root]
    Options:
            -b : run in batch mode without graphics
            -n : do not execute logon and logoff macros as specified in .rootrc
            -q : exit after processing command line macro files
            -l : do not show splash screen
           dir : if dir is a valid directory cd to it before executing

        ?        : print usage
       -h        : print usage
      --help    : print usage
      -config  : print ./configure options

    Choose [dir] and [file] via panel. There is a sample *.root file in the examples
    sub-directory.

     

    This page was created by Janet Seyboth on March 7, 2006

    Overview

    This page was updated by Janet Seyboth on January 25, 2001

     

    Reconstruction

     

    FTPC Reconstruction

     

     

     

    Hit Finding

                                   StFtpcClusterMaker Documentation

    If raw data already exists, either produced by the FTPC slow simulator (StFtpcSlowSimMaker) or from a daq data import, StFtpcClusterMaker will immediately invoke the cluster finder StFtpcClusterFinder . Otherwise, the FTPC fast simulator StFtpcFastSimu will be invoked to generate hits from geant data.


     

    Tracking

     

    StFtpcTrackMaker - FTPC Conformal Mapping Tracker

    The StFtpcTrackMaker replaces St_fpt_Maker in the FTPC reconstruction chain.

     

    StFtpcTrackMaker uses the clusters from StFtpcClusterMaker to reconstruct the tracks in the FTPC using conformal mapping. A list of all the "found" hits along with the number actually found and the maximum number of hits possible are saved for each track.

    Then these "found" hits are fit using a 2x2-D track fitter. The impact parameter at the pre-vertex is calculated. All tracks with an impact parameter less than max_Dca are flagged as primary track candidates whose vertex is the pre-vertex. The momentum fit results for the unconstrained fit are saved in the track table.

     

  • Software documentation
  • FTPC Tracking Algorithms
  • Efficiency and contamination plots
  • Contamination study
  • Some nice pictures
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     14553 Geant hits (about 1000 tracks per Ftpc) after being tracked with the new Conformal Mapping Algorithm.


    Markus Oldenburg

     

    Last modified: Apr 20 2005

     

     

     

     

    Simulation

     

    FTPC geometry

    • ftpcgeo  - FTPC geant geometry definitions

     

    Momentum Resolution

     

    Mock Data challenges

     

    FTPC Fast Simulator

     

    FTPC Slow Simulator

     

     

     

     

     

    HF Momentum Resolution Study

     

    FTPC Half Field Momentum Resolution Study

    This page shows results of some tests done in Munich to estimate the effect running at half the normal magnetic field strength would have on the FTPCs' momentum resolution.

    The tests were done comparing the momentum resolution of two venus runs produced for mock data challenge 2. MDC 2 data is not very suitable for FTPC testing as it was calculated at extremely high geant resolution, so that each track caused several hits in each padrow. However, all the available data at half field is from MDC 2.

    One event of each run was processed through the fast simulation chain, assuming that the quality of ExB corrections will not change with the field strength. Fast simulation makes it possible to compare reconstructed tracks to geant tracks by simply comparing the constituent points.

    The plots show the reconstructed momentum divided by the geant momentum and are in good agreement with earlier studies done with realistic simulation parameters and the measured magnet field. (Earlier simulations done by Michael Konrad assuming a perfectly uniform field looked somewhat better.) Only perfectly reconstructed tracks with 10 hits that actually belonged to the same geant track are used in the plot.

    The first plot shows the resolution at full magnetic field, the second at half field. Both peaks are nicely centered around one, showing essentially correct momentum resolution, but the RMS of the distribution increases from 15 to 20 percent when going to half the magnetic field. This is in contradiction with the obvious assumption of a linear increase of the errors, which, however, is not really to be expected at closer inspection. Also, the number of properly reconstructed tracks is smaller in the second plot, but it is yet unclear if this is due to a larger range of delta spirals in the smaller field, to some other effect or just statistics.

    Full field:

    Half field:

     


     

     

    MDC1

    FTPC and MDC1

    The FTPC slow simulator chain:

    • fss --- The FTPC Slow Simulator
    • fcl --- The FTPC CLuster finder
    • fpt --- The FTPC tracker
    • fte - track evaluator

       

    was included in the bfc.kumac for MDC1. NO dst information was written out.

    Results:

    We were able to find and correct programming errors which caused NaN's.

    This page was written by Janet Seyboth on February 6, 1999

     

     

    MDC2

    FTPC and MDC2

     

    In MDC2, the GEANT step size in the FTPC acceptance was reduced, so that every passing particle left a series of geant hits in every padrow. This became a serious challenge for the FTPC software and, even after optimization, increased the calculation time significantly. To get high-statistics for strangeness studies in the TPC, the planned schedule was changed in favor of more TPC fast simulator runs. Therefore, only a small number of events was run through the FTPC chain in MDC2, both with and without the slow simulator.

    The complete FTPC slow simulator chain was run in the ROOT chain macro (bfc.C):

    • St_fss_Maker --- The FTPC Slow Simulator
    • St_fcl_Maker --- The FTPC CLuster finder
      In runs when no raw_data from the FTPC slow simulator exists, St_fcl_Maker ran the FTPC fast simulator module
      ffs.

       

    • St_fpt_Maker --- ran the following FTPC modules:

      fpt - track finder

      fte - track evaluator

      fde - dE/dx calculator

    The FTPC track, point and dE/dx information was written out to the dst by St_glb_Maker.

    This page was written by Janet Seyboth on February 6, 1999

     

     

    MDC4

    FTPC and MDC4

    BNL, April 26 - May 10, 2001

    Status History for FTPC in MDC4

    Reconstruction

    Purpose - MDC4 gave us the opportunity to test the performance and stability of our reconstruction chain with a large amount of simulated data before real data taking begins. It was the first large scale test of our slow simulator and cluster finder.

    MDC4 Datasets - Dataset A (20,000 Au+Au MEVSIM events), DataSet B (100,000 pp PYTHIA events) and Dataset C (Au+Au peripheral STARLIGHT events) were processed in MDC4

    BFC Chains - The FTPC ran only in the Au+Au BFC chain since our simulators can not handle pile-up

    starnew new->SL00d

    ROOT 3.00.06

    bfc.C(#events,"MDC4","input dataset")

    Identified Reconstruction Tasks

    Implement StAssociationMaker

    Pileup - we have to add pileup to our simulators in order to process pp simulation data (Contact: Akio,Jan)

    Chisq - determine the correct values for the $STAR/StarDb/ftpc/ftpcClusterPars.C parameters 
                       timeDiffusionErrors[1]
                       timeDiffusionErrors[2] 
    

    Reconstructed Datasets on FTPC BNL Cluster

    There are 80 MEVSIM events in /cassini/data1/MDC4/Gstar/rcf0181_01_80evts.fzd

    A complete set of output *.root files for these 80 events is available in /cassini/data1/MDC4

    Analysis

    Status - The analysis half of MDC4 was held for Friday, May 4 - Thursday, May 10

    PWGs Expectations - The analysis focused on the new detectors and their physics capabilities

    Spectra PWG - larger acceptance with FTPC

    EbyE PWG - flow with FTPC

    Strangeness PWG - first attempts to find v0's in FTPC

    MDC4 Status Meetings

    There was a telephone conference each Tuesday and Thursday at 3pm EST in the White Pit in Bldg. 118 (dial in x8261)

    MDC4 Wrap-up Meeting

     

    On Thursday, May 10 starting around 1:30pm EST there was a wrap-up meeting. Each sub-system was requested to summarize their experiences gained in MDC4 regarding efficiencies,problems encountered, etc. This summary should also contain a short summary on the new physics capabilities

    JPWG Meeting

    A PWG Workshop was held for Thursday, May 10 - Monday, May 14


    This page was written by Janet Seyboth on April 27, 2001

     

    Sim vs. Real Data - dAu

    Comparison Slow Simulator and Real data dAu Min Bias


    The Distribution of the number of hits-on-global-track is NOT the same for Real Data and Simulation with Hijing through the Slow Simulator (?) What happens with all this 10-hit-on-track ? The used Gain Table is not good enough to reproduce the holes?
     
     

    FTPC West FTPC East
    AuAu minbias with low multiplicity in comparison with dAu min bias REAL DATA and SIMULATION AuAu minbias with low multiplicity in comparison with dAu min bias REAL DATA and SIMULATION
    REAL DATA SIMULATION

     

    The residuals are much better for Simulation than for Real data. We still need to do something here )-:

     

     

    Sim vs. Real Data - AuAu

    Comparison Slow Simulator and Real data for AuAu minbias events

    The trend with the variation of the number of hits on track with the multiplicity is the same for Real Data and Simulation with Hijing through the Slow Simulator
     
     

    FTPC East
      AuAu minbias REAL DATA from Low Multiplicity (red) to High multiplicity (blue) AuAu minbias SIMULATION from Low Multiplicity (red) to High multiplicity (blue)
    FTPC West
      AuAu minbias REAL DATA from Low Multiplicity (red) to High multiplicity (blue) AuAu minbias SIMULATION from Low Multiplicity (red) to High multiplicity (blue)

     

    The residuals are much better for Simulation than for Real data. We still need to do something here )-:

     

     

    StFtpcFastSimu

    StFtpcFastSimu - FTPC Fast Simulator

    The FTPC fast simulator is implemented in C++ (as a part of StFtpcClusterMaker).

    It was converted from Fortran (pam/ffs) to C++ by Holm Hümmler and is supported by Janet Seyboth.

    StFtpcFastSimu simply takes the hit points registered by geant and turns them into FTPC points. Some cuts are applied to remove points that are outside the sensitive volume of the FTPC sectors and to account for the loss of hits due to cluster merging. Some of the geant information is kept in the gepoint table to be used in efficiency studies.

     

    ftpcgeo

    ftpcgeo.g

    ftpcgeo.g defines the geometry for the FTPC in geant simulations. It contains information about the main aluminum cylinder, its support structures, the fieldcage and a rather detailed description of the readout chambers, and it defines the sensitive volumes.

    Other geometry files of interest for the FTPC simulation are pipegeo.g for the beampipe and svttgeo.g with a description of the SVT, its support cone, the beampipe support and the shield layers.

    This page was updated by Holm Hümmler on September 16, 1999