Luca Stanco - INFN Padova
Krakow, 28 September 1999





1
Setup reminder
Status of the Limited Streamer Tubes (LST)
Triggers
Efficiencies
Y2K, online hang-up etc.
Luca Stanco - INFN Padova
RMUON
BMUON
2
Luca Stanco - INFN Padova
 ~ 3 600 LSTs (with lenght from 0.7 to 10.2 m)
 ~ 43 000 8-bit analog channels
 ~ 29 000 digital channels
Area detector > 2 000 m2
Resolution:  1 mm in the “strip” view
 3 mm in the “wire” view
Technical Coordinator: Riccardo Brugnera
Web-master: Vincenzo Chiochia
3
Luca Stanco - INFN Padova
Mortality...
year
BMUI BMUO RMUI RMUO
Total
Ch72
1994
78
59
41
23
201
34
1995
-
-
-
-
-
-
1996
78
59
42
23
202
36
1997
79
59
45
33
216
25
1998
81
66
50
41
238
25
1999 81/708 66/1502 50/480 41/704 238/3394 25/184
plus ~ 68 LST in trip for 10-40% of time
plus ~ 10 LST in trip for 10-40% of time
4
Luca Stanco - INFN Padova
Dead LST’s are normally switched off
Simulation in the Monte Carlo
via an EAZE job:
to evaluate efficiency dependence
(small effect: 5%)
BMUON
- MC ideal
efficiency
- - MC with
dead LST
RMUON
5
Luca Stanco - INFN Padova
Slot 8: Elastic
Slot 10: Inner BMUON
Slot 11: Inner RMUON
Slot 14: Outer BMUON
Slot 15: Outer RMUON
Inner
Outer
• GLOMU
• GLOEXO
6
Luca Stanco - INFN Padova
rates...
1 mb for L = 10*1030  10 Hz (most of the runs
7
Luca Stanco - INFN Padova
with INNER chambers
and with ISOMU: Calorimeter regions
8
Luca Stanco - INFN Padova
rates
INNER
OUTER
9
Luca Stanco - INFN Padova
GLOMU rates
cosmics
30 nb for L = 10*1030  0.03 Hz
10
Luca Stanco - INFN Padova
independent setup: efficiency vs HV
working value
11
to reduce trips
Luca Stanco - INFN Padova
100%
HV: 4700
88%
100%
HV: 4550
75%
include inefficiency factor on single
LSTin the Monte Carlo (15%)
12
Luca Stanco - INFN Padova
- MC ideal
- - MC with dead LST and 15% factor for HV
efficiency
BMUON
RMUON
15% inefficiency coherent with analysis of single track segment !
13
Luca Stanco - INFN Padova
Check efficiency with DATA themselves
!
Two independent analysis on 2 track m+m- clean events
(3 different set of events, depending of the trigger)
BMUON
SET 1
SET 2
14
Luca Stanco - INFN Padova
Monte Carlo is off of an overall factor !
A few investigations performed.
Not yet found out the reason...
… much more in Alessandro Bertolin’ talk
this afternoon
15
Luca Stanco - INFN Padova
VMS computer for DAQ
• patch from DEC (and spare mVAX from DELPHI available)
• upgrade on going ...
Slow Control with OS9 (version 2.3 NOT good)
• manual patch (bring time back, uff !) …
• upgrade to 3.03 ?
16
Luca Stanco - INFN Padova
problem while Aborting Run ?
Time for Aborting as function of Run ...
17
Luca Stanco - INFN Padova
Distribution of Time for Aborting ...
for last positron runs...
18
Luca Stanco - INFN Padova
• Good general behaviour of the detector
• Triggers under control
• Efficiency studies on the way on
• Few upgrades needed for next millenium
Good perspectives
for next millenium Runs
19
Luca Stanco - INFN Padova