Difference between revisions of "Tracking Configuration Parameters"
(Initial template. No descriptions yet!) |
(Part way through. Saving work.) |
||
| Line 34: | Line 34: | ||
| − | =TRKFIND:EXCLUDE_STEREO= | + | =TRKFIND:EXCLUDE_STEREO= |
| + | Exclude CDC stereo layer hits from the track finding. This was implemented when track finding was done using truth information and may not make sense once a real hit-base track finder is implemented. | ||
| + | |||
=TRKFIND:MAX_CIRCLE_DIST= | =TRKFIND:MAX_CIRCLE_DIST= | ||
| − | =TRKFIND:MAX_DEBUG_BUFFERS= | + | Maximum distance in cm a hit can be away from the circle (determined by seed fit) in X/Y plane in order to be considered "on circle". |
| − | =TRKFIND:MAX_HIT_Z= | + | |
| − | =TRKFIND:MAX_PHI_Z_DIST= | + | =TRKFIND:MAX_DEBUG_BUFFERS= |
| − | =TRKFIND:MAX_SEED_DIST= | + | Several objects and histograms are used in track finding that are discarded after each candidate is found. This value is used to determine how many should be kept around in the factory so they may be accessed when debugging. The buffers are automatically cleared at the start of the next event. This does not affect the results of the track finding. |
| − | =TRKFIND:MAX_SEED_HITS= | + | |
| − | =TRKFIND:MIN_CANDIDATE_HITS= | + | =TRKFIND:MAX_HIT_Z= |
| + | Upper limit of z-value for hits that are included in track finding. This is used with TRKFIND:MIN_HIT_Z to specify a range of z-values for the hits used in track finding. The purpose is to limit ourselves to hits that fall in the high-field region of the solenoid. This may only make sense when finding with truth info since individual CDC hits do not contain z-information. A plot of the field region can be seen here: [[Track Finding/Fitting 2006]] | ||
| + | |||
| + | =TRKFIND:MAX_PHI_Z_DIST= | ||
| + | Maximum distance in cm a hit can be from the line of R*φ vs. z defined by a helix. This is used once a circle has been fit, and the "on circle" hits have been used to determine the slope,intercept of the line in phi/z space. Hits that fall within this distance are considered "on line" and will be used in the final determination of the helical parameters for the candidate. | ||
| + | |||
| + | =TRKFIND:MAX_SEED_DIST= | ||
| + | Maximum distance in cm a hit can be in the X/Y plane from the previous hit in order to be considered part of the track seed. If the next nearest neighbor of a hit at the end of a track seed is further away than this distance, then the search for more seed hits on that end is terminated. See also TRKFIND:MAX_SEED_HITS. | ||
| + | |||
| + | =TRKFIND:MAX_SEED_HITS= | ||
| + | Maximum number of seed hits needed before passing to the helical fitter. Once this number of hits are found, it is assumed there are enough hits to do a circle fit and continue finding the track. | ||
| + | |||
| + | =TRKFIND:MIN_CANDIDATE_HITS= | ||
| + | Minimum number of hits on the final track candidate to allow it to become a true track candidate. After the final parameters for the candidate have been found using the helical fitter, one last pass is made to determine the hits that consistent with this helix. This implements a filter on candidates that don't contain at least this many hits nearby. | ||
| + | |||
=TRKFIND:MIN_HIT_Z= | =TRKFIND:MIN_HIT_Z= | ||
| + | Minimum z-value in cm a hit can be to be included in track finding. See TRKFIND:MAX_HIT_Z above for details. | ||
| + | |||
=TRKFIND:MIN_PHI_Z_HITS= | =TRKFIND:MIN_PHI_Z_HITS= | ||
=TRKFIND:MIN_SEED_HITS= | =TRKFIND:MIN_SEED_HITS= | ||
Revision as of 12:23, 12 December 2006
Here is the list of tracking configuration parameters and their defaults as printed out by hd_dump -Pprint=TRK explanations are below.
TRKFIND:EXCLUDE_STEREO = 1 TRKFIND:MAX_CIRCLE_DIST = 2 TRKFIND:MAX_DEBUG_BUFFERS = 0 TRKFIND:MAX_HIT_Z = 360 TRKFIND:MAX_PHI_Z_DIST = 10 TRKFIND:MAX_SEED_DIST = 5 TRKFIND:MAX_SEED_HITS = 10 TRKFIND:MIN_CANDIDATE_HITS = 6 TRKFIND:MIN_HIT_Z = -100 TRKFIND:MIN_PHI_Z_HITS = 4 TRKFIND:MIN_SEED_HITS = 4 TRKFIND:TARGET_Z_MAX = 80 TRKFIND:TARGET_Z_MIN = 50 TRKFIND:TRACKHIT_SOURCE = MC TRKFIND:XY_NOISE_CUT = 2 TRKFIT:CHISQ_MAX_RESI_SIGMAS = 5 TRKFIT:DEBUG_HISTS = 0 TRKFIT:LEAST_SQUARES_DP = 0.001 TRKFIT:LEAST_SQUARES_MAX_E2NORM = 1e+06 TRKFIT:LEAST_SQUARES_MIN_HITS = 3 TRKFIT:MAX_CHISQ_DIFF = 1e-06 TRKFIT:MAX_FIT_ITERATIONS = 20 TRKFIT:MAX_HIT_DIST = 10 TRKFIT:SIGMA_CDC = 0.02 TRKFIT:SIGMA_FDC_ANODE = 0.02 TRKFIT:SIGMA_FDC_CATHODE = 0.02 TRKFIT:USE_CDC = 1 TRKFIT:USE_FDC_ANODE = 1 TRKFIT:USE_FDC_CATHODE = 1 TRKMC:EXCLUDE_SECONDARIES = 0 TRKMC:MAX_HIT_R_FDC = 56.3
Contents
- 1 TRKFIND:EXCLUDE_STEREO
- 2 TRKFIND:MAX_CIRCLE_DIST
- 3 TRKFIND:MAX_DEBUG_BUFFERS
- 4 TRKFIND:MAX_HIT_Z
- 5 TRKFIND:MAX_PHI_Z_DIST
- 6 TRKFIND:MAX_SEED_DIST
- 7 TRKFIND:MAX_SEED_HITS
- 8 TRKFIND:MIN_CANDIDATE_HITS
- 9 TRKFIND:MIN_HIT_Z
- 10 TRKFIND:MIN_PHI_Z_HITS
- 11 TRKFIND:MIN_SEED_HITS
- 12 TRKFIND:TARGET_Z_MAX
- 13 TRKFIND:TARGET_Z_MIN
- 14 TRKFIND:TRACKHIT_SOURCE
- 15 TRKFIND:XY_NOISE_CUT
- 16 TRKFIT:CHISQ_MAX_RESI_SIGMAS
- 17 TRKFIT:DEBUG_HISTS
- 18 TRKFIT:LEAST_SQUARES_DP
- 19 TRKFIT:LEAST_SQUARES_MAX_E2NORM
- 20 TRKFIT:LEAST_SQUARES_MIN_HITS
- 21 TRKFIT:MAX_CHISQ_DIFF
- 22 TRKFIT:MAX_FIT_ITERATIONS
- 23 TRKFIT:MAX_HIT_DIST
- 24 TRKFIT:SIGMA_CDC
- 25 TRKFIT:SIGMA_FDC_ANODE
- 26 TRKFIT:SIGMA_FDC_CATHODE
- 27 TRKFIT:USE_CDC
- 28 TRKFIT:USE_FDC_ANODE
- 29 TRKFIT:USE_FDC_CATHODE
- 30 TRKMC:EXCLUDE_SECONDARIES
- 31 TRKMC:MAX_HIT_R_FDC
TRKFIND:EXCLUDE_STEREO
Exclude CDC stereo layer hits from the track finding. This was implemented when track finding was done using truth information and may not make sense once a real hit-base track finder is implemented.
TRKFIND:MAX_CIRCLE_DIST
Maximum distance in cm a hit can be away from the circle (determined by seed fit) in X/Y plane in order to be considered "on circle".
TRKFIND:MAX_DEBUG_BUFFERS
Several objects and histograms are used in track finding that are discarded after each candidate is found. This value is used to determine how many should be kept around in the factory so they may be accessed when debugging. The buffers are automatically cleared at the start of the next event. This does not affect the results of the track finding.
TRKFIND:MAX_HIT_Z
Upper limit of z-value for hits that are included in track finding. This is used with TRKFIND:MIN_HIT_Z to specify a range of z-values for the hits used in track finding. The purpose is to limit ourselves to hits that fall in the high-field region of the solenoid. This may only make sense when finding with truth info since individual CDC hits do not contain z-information. A plot of the field region can be seen here: Track Finding/Fitting 2006
TRKFIND:MAX_PHI_Z_DIST
Maximum distance in cm a hit can be from the line of R*φ vs. z defined by a helix. This is used once a circle has been fit, and the "on circle" hits have been used to determine the slope,intercept of the line in phi/z space. Hits that fall within this distance are considered "on line" and will be used in the final determination of the helical parameters for the candidate.
TRKFIND:MAX_SEED_DIST
Maximum distance in cm a hit can be in the X/Y plane from the previous hit in order to be considered part of the track seed. If the next nearest neighbor of a hit at the end of a track seed is further away than this distance, then the search for more seed hits on that end is terminated. See also TRKFIND:MAX_SEED_HITS.
TRKFIND:MAX_SEED_HITS
Maximum number of seed hits needed before passing to the helical fitter. Once this number of hits are found, it is assumed there are enough hits to do a circle fit and continue finding the track.
TRKFIND:MIN_CANDIDATE_HITS
Minimum number of hits on the final track candidate to allow it to become a true track candidate. After the final parameters for the candidate have been found using the helical fitter, one last pass is made to determine the hits that consistent with this helix. This implements a filter on candidates that don't contain at least this many hits nearby.
TRKFIND:MIN_HIT_Z
Minimum z-value in cm a hit can be to be included in track finding. See TRKFIND:MAX_HIT_Z above for details.
