OPERA 2008 run: a report from the Swiss scanning lab
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Transcript of OPERA 2008 run: a report from the Swiss scanning lab
OPERA 2008 run: a report from the Swiss scanning lab
Ciro Pistillo
LHEP Bern university
for the Swiss scanning team
OPERA Collaboration meeting Ankara, April 1-4 2009
Status of event location
TOTAL CC NC BLACK CS
Received events
126 105 21 11
Received bricks
127 106 21 11
Valid events
124 105 19 10
Analyzed events
122 103 19 8
Status of event location
TOTAL CC NC BLACK CS
Located in ECC
101 87 14 4
Located in dead
material2 1 1 -
Passing through
7 5 2 1
Analysis completed
110 93 17 4
Connected 115 96 19 5
Pending 12 10 2 3
Scanning now
2 2 - 2
Status of publication
Bricks:
85 / 101 published in central DB
Vertices:
78 / 101 published in central DB
Vertex position
Plate number
Prong multiplicity
TOTAL
CC NC
Impact parameter
IP (not mu) Δz < 1300
IP (mu)
IP < 10 m
IP < 10 m
large angle black tracks
IP (not mu)
Interesting topologies
Event no. 231012915 located in brick 72853
Event no. 228197639 located in brick 14653 (NEW)
Event no. 228563573 located in brick 79117 (NEW)
top view
beam view
mumu
side view
I.P. w.r.t. the vertextrk 145 0.3563 0.1562 0.5 mtrk 206 -0.2815 -0.2423 0.4 mtrk 541 -0.0001 0.0303 62.8 m (mu)
145
541
mu
72853
mu momentum in spectrometer: 17.2 GeV/c decay Pt > 5 GeV
(p22-56 used) daughter angle and momentumtrk145: TX: 0.3519 TY: 0.1485 P = 1.685 -0.447 + 0.951 GeV/c trk206: TX:-0.2698 TY:-0.2425 P = 1.323 -0.351 + 0.747 GeV/c
using these values estimate the mass of the D0 using 3 possibilities for daughters: -Kaon-Pion: 1.26 GeV (+0.52 -0.23) -Pion-Kaon: 1.30 GeV (+0.52 -0.22) -Pion-Pion: 1.09 GeV (+0.58 -0.27) -these values are below the D0 mass (1.864 GeV). -Problably a neutral is missing (also according to the topology).
Muon angle: KALMAN 0.150 0.305
LINEAR 0.144 0.303
14653
ΔZ = 51 m
8 prong vertex or very short decay?
Vertex located in the lead upstream the plate 51
kinematical analysis not possible (downstream brick extracted)
Primary vertex: 59711.0 54774.6 -8818.2Secondary vertex: 59707.3 54769.4 -8767.2
ID X Y Z TX TY IP1 59835.3 55044.4 -8085.4 0.1684 0.3739 4.2 mu momentum 3.7 Gev/c (TT) 2 59607.9 54880.4 -8085.4 -0.1433 0.1437 2.0 3 59514.8 54836.6 -8085.4 -0.2635 0.0789 5.1 4 59898.8 54731.1 -8085.4 0.2570 -0.0548 3.4 5 59535.8 54453.7 -8085.4 -0.2349 -0.4370 3.0 6 59607.2 54412.4 -8085.4 -0.1444 -0.4977 2.9
7 59731.5 54812.4 -8085.4 0.0356 0.0628 0.3 // 10.0 wrt 1ry 8 59624.4 54752.8 -8085.4 -0.1222 -0.0233 0.8 // 5.6 wrt 1ry
All the tracks have been measured in the first plate downstream the primary vertex.
IP distribution
79117
pl 33: 1ry vertex + short charm candidate
secondary interaction
id 8 found in single BT search (low mom, gray)
id 1 mu (not found in CS)
id 7 CS pred
id10 CS pred
id 2
id 3 CS pred
id 5 found in single BT search (low mom)
id3
id2
id1(mu)
id8
id10
Hypothesis (1) 1ry vtx + short vee (daughters: id 3 and id 2)
1ry (103979.1 45758.9 -32325.8) id 1 -0.0318 0.0911 IP wrt 1ry = 0.2 (mu)id10 0.1998 0.2805 IP wrt 1ry = 2.2id 8 0.3420 -0.0740 IP wrt 1ry = 6.5 (gray)id 5 -0.1709 0.0289 IP wrt 1ry = 9.4 (~0.4 GeV)
short vee (103933.6 45782.1 -31727.2) id 2 -0.0685 0.0530 IP wrt vee = 0.3 IP wrt 1ry = 9.4 id 3 0.0050 -0.1310 IP wrt vee = 0.6 IP wrt 1ry =111.8
Beam view
Δz = 599 m
id3
id2
id1(mu) id10
Hypothesis (2) 1ry vertex + short kink (daughter: id 3)
1ry (103979.1 45758.9 -32325.8) id 1 -0.0318 0.0911 IP wrt 1ry = 4.3 (mu)id10 0.1998 0.2805 IP wrt 1ry = 8.0id 2 -0.0685 0.0530 IP wrt 1ry = 3.2id 8 0.3420 -0.0740 IP wrt 1ry = 15.8 (gray)id 5 -0.1709 0.0289 IP wrt 1ry = 12.3 (~0.4 GeV)
short kink daughter id 3 0.0050 -0.1310 IP wrt 1ry =122.7min. kink angle 0.158
Beam view
Result of momentum measurement (preliminary)
id 1 p = 17.0 GeV/c (TT)
id10 p = 4.0 (-2.3 ,+14.4) GeV/c (90%CL) (pl 33-56)id 2 p = 8.8 (-5.5 ,+21.4) GeV/c (90%CL) (pl 33-53)id 3 p = 5.5 (-3.8 ,+10.2) GeV/c (90%CL) (pl 33-56)id 5 p = 0.4 (-0.3 , +1.3) GeV/c (90%CL) (pl 33-39)id 8 gray, not reconstructed
Invariant mass (tracks 2 and 3)K -K : 1.7 (+1.4 -0.4) GeVpi-K : 1.6 (+1.5 -0.4) GeVpi-pi : 1.4 (+1.5 -0.5) GeVK -pi : 1.5 (+1.5 -0.4) GeV
Event 234676119 in 87219: CC or NC?
angle: Kalman -0.110 -0.092
Linear -0.114 -0.063
momentum: 0.87 GeV/c
not found in CS and not found at the primary vertex
should we consider it as a NC?
VTX POS.: 20206.70 32517.10 -12668.10 Tracks angle and IP 0.0285 -0.0179 0.00 -0.3662 0.1468 3.80 -0.0367 0.5623 9.00
127J
ul0
8
Jan
09
Se
p0
8
Ap
r09
10 bricks/week
5.3 bricks/week
Received bricks
Scanning capability for 2009 RUN
15 bricks/week (max) 12 bricks/week (steady) (only location)
10 bricks/week (steady) (including 20% SF and ex.tot.)
“only location” includes charm search: TS of 10 plates downstream
Including:
ScanForth done for all the located events
Extendend TotalScan
20 plates downstream the primary vertex (~50% of the events)
Scanning load is twice wrt “only location”
Conclusions
124 events received
Analysis successfully completed for 110 events
101 neutrino interactions located in the ECC
3 charm candidates
Focus now on charm search: check stopping tracks with large IP wrt to the vertex
Scanning capability 10-15 bricks/week (500-750 in total)
We are ready for the 2x of the 2009 run!