Algorithm works both on real data and MC.
- 1. Algorithm
The vertical slope of SVD segment is compared with direction from RICH. Then the momentum is estimated by prolongation of SVD segment in the region behind magnet where horizontal component compared with RICH segment ( by method of least squares). At the end the likelyhood function for RICH rings (RISE) is called. If no hypothesis is found for the given combination ( 5 sigma cut), it is rejected.
The magnet is supposed to be ON. If the magnet is OFF the algorithm considers both slopes and no momentum calculation is performed.
- 2. Selection of objects to be matched
- SVD : taken from RSEG ArteTable
- rseg->fit == 0
- (rseg->cmp & Rsegc::bitsign) == 0
- rseg->cmp == Rsegc::vxd || rseg->cmp == 65537(CATS)
- the end point of RSEG is considered for match
- RICH : taken from RSEG ArteTable
- (rseg->cmp & Rsegc::bitsign) == 0
- rseg->fit == 8 || rseg->fit == 10 || rseg->fit == 12 || rseg->fit == 13
- rseg->cmp & Rsegc::rich
- 3. Match Parameters
- DEFAULT
- rcSVDRichConst;
optimized with ARTE-03-05 on real data
- match based on { TY \} variable;
- Z of plane of match = 200 cm
- abs( delta_TY ) < 0.003 rad;
- $\chi^2$ cut < 150;
- no check on combination with given object to be matched;
- SOFT
- -rcSoftSRConst
optimized with ARTE-03-05
- match based on { TY \} variables;
- Z of plane of match = 200 cm
- abs( delta_TY ) < 0.005 rad;
- no $\chi^2$ cut is used;
- no check on combination with given object to be matched
- MAGNET OFF
- rcSVDRichNoMagConst;
optimized with ARTE-02-07 on MC
- match based on { TX, TY \} variable;
- Z of plane of match = 200 cm
- abs( delta_TX ) < 0.005 rad;
abs( delta_TY ) < 0.004 rad;
- $\chi^2$ cut < 120;
- the allowed number of combinations is 2-1
- 4. Call Sequence
- -
- RECON/MATCH marple VDS RICH
- from user.kumac, if standard reconstruction for real data is called
or- void matchsvdrich_();
- from usevnt_() if no reconstruction is called
- 5. Recomendations
- The algorithm was tested and used for real data december'99 with ARTE-03-05-r1. The programs used for subdetector parts were CATS and RISE. It could be usefull if the RICH standalone algorithm is used and no match OTR-RICH applied. The ghost rate is high.
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