==================== p=(1,2) pt=(0.7,0.9) ==================== tracks passing through vt1 only e.g. positives nr 1 vt1+vt2(both parts)+mt /wrong side/ e.g. pos nr 3 vt1+vt2(both parts) /wrong side/ e.g. pos nr 4 COMMENTS: 1) tracks are short -> often v.poor precision in b (e.g. pos 88) error(b) sometimes enormous (100cm) -> mom.resolution ??? (e.g. postives, 12,17,26,40,43) Due to small nr of points, a/p calculation not v.reliable (e.g. pos 12) some cases found with strange a/p 2) tracks may be very difformed in y (e.g. pos 41) 3) often some (1-2) points lost, which in case of such short tracks may be serious for dE/dx. note: these points are sometimes present as lightblue (e.g. pos 31), sometimes they are absent (e.g. pos 30). 4) splits present only for wrong side tracks. after scanning event 1177 appears that a large nr of tracks present in vt1 which should continue to vt2/mt may in fact be splits (due to inexact field??) 5) wrong side tracks have much more points than right side ones, but most of problems seen for wrong side two categories are present in detailed description below: BAD- considered bad DOUBTS- causing any doubts (much less important) NOTE: it should not be surprising that enumerating does not include certain letters as some problems found are not present ofr this sample. -------------------------- overall statistics for bad -------------------------- problem positives negatives right side wrong side right side wrong side A) joined tr 0 1 1 1 B) large a/p 1 0 0 2 C) split cl.? 0 1 2 2(*) D) splits-serious 0 2 0 3 splits-candidates 0 2 0 12(**) E) lost parts 0 3 0 1 F) lost points 0 3 0 0 G) strange stuff 0 0 0 0 (*) the possible split clusters appear for many points for wrong side and only around 1 point for right side (**) this number has been established after scanning event 1177 (negatives, 25) this casted doubt onto many worng side tracks. Probably this number should then be bigger for negatives ========= detailed positives ========= BAD --- A) JOINED TRACKS 32: wrong side, joined tracks 30,19, common points removed correctly, but why a/p=87% (should be around 100%) will be removed by b cut B) LARGE A/P VALUES 12: 2 points lost, and still a/p=137% ! C) SPLIT CLUSTERS ? 99: wrong side, split clusters at z=-350 cm? difficult to say whether points chosen correctly. D) SPLITS / CANDIDATES FOR SPLITS 8 : . wrong side, split? 39: wrong side, 2nd part lost- kink? 52: . wrong side, tr. 25 split due to poor momentum, tr 12 should be rejected 74: wrong side, crazy way of finding points vt2 (split suspected) E) LOST PARTS 38: wrong side, many points lost in vt2 (a/p=87%), should be rejected by a/p cut 46: wrong side, many points lost vt2 (a/p=85%), crazy way of finding/rejecting points mt 92: wrong side, vt1: 8 points lost from 19 (a/p=61%)! (vt2,mt parts lost as well), will be rejected by a/p cut F) LOST POINTS 64: wrong side, several points lost in vt1 (a/p=90%), mt part lost 80: wrong side, track 18:2 points lost, 1 of them assigned to another track (24) 86: wrong side, 4 points lost vt2 (all of them seem closer than 9 mm) DOUBTS ------ A) A/P OR LARGE DISTNACE FOR POINTS 75,76,77: points caught at large y distance C) STRANGE STUFF 13: points found in mt, why a/p=-1% ? D) SPLITS / CANDIDATES FOR SPLITS 36,41,43,56: 2nd part lost -> scattering in magnet? 24: wrong side, 2nd part lost -> scattering in magnet? 51: mt part lost, otherwise o.k ========= detailed negatives ========= BAD --- A) JOINED TRACKS 8: wrong side, joined tracks 19,16 common points removed correctly, but why 1st fitted point not corrected? (could be not recognized v0?) 40: right side, joined tracks 14,17 common points removed correctly, but why 1st fitted point in this place (could be much earlier)? B) LARGE A/P VALUES 59: wrong side, 1 point lost, a/p=200% SEE ALSO 48 in D) C) SPLIT CLUSTERS ? 23,72: right side, 1 split cluster? 28,47: wrong side, split clusters? D) SPLITS / CANDIDATES FOR SPLITS 48: . wrong side, SPLIT TRACK, vt1 part lost, why a/p(vt2)=167% ??? - dangerous a/p may fake a good track /p=(0.708 -0.161 0.921)/ 25: . wrong side, in principle track correctly abandonned when getting out of vt1 -> when event examined, appears that most of this track is lost due to bad tracking (inexact field?), giving a split. SUSPECTED the same happening for: 22,30,31,49,56,59,62,66,68,94,98 (all wrong side tracks) 93: wrong side, suspected same as above, red point(s) could be part of the split... 95: . wrong side, suspected same as above, red point(s) could be part of the split... E) LOST PARTS 78: wrong side, many points lost in mt (points are present-lightblue) DOUBTS ------ A) A/P OR LARGE DISTNACE FOR POINTS 2: wrong side, point caught at 1 cm x distance in vt1 ? (z=-410) 4: wrong side, 1 point lost, a/p still 111% 13: wrong side, point caught at 1 cm x distance in vt1 (z=-400),1 point lost, a/p=109% 16: wrong side, point caught at 1 cm x distance in vt1 (z=-300) 74: wrong side, point caught at 1 cm y distance in vt1 ? (z=-275) B) SPLIT CLUSTERS? 35: wrong side, split cluster(s) at z=-440? 53: wrong side, split cluster(s) at z=-360? 61: wrong side, split cluster(s) at z=-400? 65: wrong side, split cluster(s) at z=-410? 68: wrong side, split cluster(s) at z=-400? C) STRANGE STUFF 79: wrong side, non vertex? will be rejected by cuts but still strange it managed. 88: wrong side, how can one have a/p=97% with 47 points? Positives 25 ++-**---------+--------------+-------------+--------------+------------++ 20 ++*** + + + + ++ 15 ++* * ++ | * **** | 10 ++* * ++ 5 ++* *** **+ ****** +*** + + ++ 0 ***------*********----*********-*************************************--++ 0 50 100 150 200 250 Number of points Negatives 25 ++-$$---------+--------------+-------------+--------------+------------++ 20 ++ $$ $$ + + + + ++ 15 ++ $$ $$ ++ | $$$$$$ | 10 ++$ $ ++ 5 ++$ $$$$$$ + $$ $$ + + ++ 0 $$$---------$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$--++ 0 50 100 150 200 250 Number of points