mary bishai (minos collaboration) · status of the minos experiment next generation of nucleon...
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Status of the MINOS experimentNext Generation of Nucleon Decay and
Neutrino Detectors 8/04/2005
Mary Bishai (MINOS collaboration)
Mary Bishai, BNL 1 – p.1/33
OutlineIntroduction to MINOS
Physics sensitivities
Status of MINOS:
MINOS Far Detector (FD)
Calibration Detector
NuMI beamline
commisioning
MINOS Near Detector (ND)
First beam neutrino events in FD & ND
Mary Bishai, BNL 2 – p.2/33
INTRODUCTION TO NuMI/MINOS
Mary Bishai, BNL 3 – p.3/33
NuMI/MINOS ConceptFar Detector
735 km
11.1 km
Fermilab Soudan
Near Detector0.98 kT 5.4 kT
Fermilab’s Main Injector, Illinois
120 GeV protons, 2.5 × 1013 pro-
tons/ 8µsec pulse, 1.9 sec rep rate.
⇒ 0.25 MW
Soudan Underground Lab, Minnesota
Mary Bishai, BNL 4 – p.4/33
MINOS Beam Spectrum
LE beam at 2.5 × 1020 POT/yr ⇒ expect 1600 events/yr in FD
Mary Bishai, BNL 5 – p.5/33
MINOS νµ Disappearance
Plot ratio of yield at far
det. to expected from
near det.
Location and depth of dip
yield δm2 and sin2 2θ
Assume δm2 = 0.0025
eV2, sin2 2θ = 1.0
3 years at nominal intensity (top). Intensity upgrades (bottom)
Determine δm2 to 10 % Rule out exotic oscillation models
Mary Bishai, BNL 6 – p.6/33
MINOS νe Appearance Sensitivity
Detection of νe at ∆m2atm
. Evidence for non-zero θ13
Mary Bishai, BNL 7 – p.7/33
THE FAR DETECTOR
Mary Bishai, BNL 8 – p.8/33
The Far Detector
8m × 2.54 cm thick Fe plates
4.1w × 1d × 800l cm
scintillator strips with WLS fiber
readout. 486 layers ⇒ 5.4kTon
Toroidal B-field, 1.3 T at r = 2m
Cosmic µ veto shield
Mary Bishai, BNL 9 – p.9/33
Upward going muons in the FD
2.4 ns single hit timing resolution
Mary Bishai, BNL 10 – p.10/33
FD Cosmic Ray Physics
Based on ∼ 1yr of data:
1/β = cδt/δs
MC: Nuance w/Bartol ’96 flux.
No-osc normalized to data.
Zenith angle distribution.
Mary Bishai, BNL 11 – p.11/33
Far Detector: Moon’s Shadow
Mary Bishai, BNL 12 – p.12/33
The Calibration Detector
Mary Bishai, BNL 13 – p.13/33
COMMISIONING THE NuMI BEAMLINE
Mary Bishai, BNL 14 – p.14/33
NuMI Primary Beamline
Mary Bishai, BNL 15 – p.15/33
NuMI Pretarget
Mary Bishai, BNL 16 – p.16/33
Measuring the Beam Profile
Mary Bishai, BNL 17 – p.17/33
Measuring the Beam Position
Characteristics of NuMI Beam Posi-
tion Monitors:
Software algorithm to search
400 µsec to find the beam.
NuMI bunches come in 6
batches from booster. Position
is measured batch by batch.
Linear over 15-20 mm. 50 µm
resolution.
BPMs used to auto-steer the beam to target center
Mary Bishai, BNL 18 – p.18/33
Target Region Components
Target Enclosure
6.4 x 28 mm2 graphite segments. 1m
long = 1.9 interaction lengths. O(10)
KW beam power at 1 mm beam width.
Water cooled.
Horn 1
Parabolic magnetic lens.
Mary Bishai, BNL 19 – p.19/33
Muon and Hadron monitorsParallel-plate ionization chambers are used to monitor hadron and muon
content of secondary beam.
Mary Bishai, BNL 20 – p.20/33
Online Beam Status
Mary Bishai, BNL 21 – p.21/33
Target position scanUse low intensity beam and scan
across targetMaximum P.H. when beam
passes between target and
graphite protection baffle.
Horizontal scan (cm) Vertical scan (mm)
Mary Bishai, BNL 22 – p.22/33
Horn current scanAs horn current changes we focus different π energies. More current
⇒ more focusing
As target position changes we focus different energy πs. Larger
target/horn separation ⇒ higher π energy
LE position ME Position HE Position
Mary Bishai, BNL 23 – p.23/33
NuMI Beamline Performance
Date (2005)12/01 12/15 12/29 01/12 01/26 02/09 02/23 03/09 03/23
Date (2005)12/01 12/15 12/29 01/12 01/26 02/09 02/23 03/09 03/23
Prot
ons p
er S
pill (
1E12
)
0
5
10
15
20
25
30
35
40
45
50
NuMI Protons
Tota
l Deli
vere
d Pr
oton
s (1E
17)
0
1
2
3
4
5
6
7
8
9
10
Brett Viren, 2005/03/28
Wed March 23: target vacuum compromised. Cooling water in target enclosure.
Incident under investigation.
Mary Bishai, BNL 24 – p.24/33
THE NEAR DETECTOR
Mary Bishai, BNL 25 – p.25/33
The Near Detector
Calorimeter region
Spectrometer region
Mary Bishai, BNL 26 – p.26/33
ND 1st Beam Neutrino Jan 21, ’05
Intensity was around
2.5 × 1012 pro-
tons/spill.
Target in the ME posi-
tion.
Mary Bishai, BNL 27 – p.27/33
ND Lots and Lots of νs
At 2.5 × 1013 p/spill
Target is in ME posi-
tion.
ND scintillator read-
out has 19ns resolu-
tion (same as bunch
length).
Timing information
is used to separate
events.
Run: 6578 Snarl: 118 All 21 Slices
Reconstruction Summary Tracks: 16 Showers: 15
AltTimeHistEntries 6689Mean 0RMS 0Underflow 0Overflow 1.146e+06
507.388 507.39 507.392 507.394 507.396 507.398 507.4 507.402 507.404
610×-1
-0.5
0
0.5
1
AltTimeHistEntries 6689Mean 0RMS 0Underflow 0Overflow 1.146e+06
U
-4
-2
0
2
4
V
-4
-2
0
2
40 5 10 15
Y
-4
-2
0
2
4
X-2 0 2 4
0
50
100
0
50
100
UZ PE VZ PETimeHist
Entries 6689Mean 8.373e+08RMS 2900Underflow 0Overflow 0
837.332 837.334 837.336 837.338 837.34 837.342 837.344 837.346 837.348
610×0
50
100
150
200
250
300
310× TimeHistEntries 6689Mean 8.373e+08RMS 2900Underflow 0Overflow 0
Mary Bishai, BNL 28 – p.28/33
ND Beam Neutrino Properties
Time difference between ND
hits and beam extraction.
NuMI 18.87ns bunches come in
5 batches.
Angle between µ track direction (both rock
and contained) and beam direction:
Mary Bishai, BNL 29 – p.29/33
1st FD Beam Neutrino, March 7 ’05
Mary Bishai, BNL 30 – p.30/33
Far Detector Beam Neutrino #2
Mary Bishai, BNL 31 – p.31/33
ConclusionsNuMI construction is now OFFICIALLY OVER
The MINOS experiment had begun.
Beamline commisioning is well underway. Initial design goal of2.5 × 10
13 protons/pulse and the 2 second rep. rate have beenachieved separately.
Main Injector and Booster improvements planned to increaseintensity to 4 × 10
13 protons/pulse with a 2 sec. rep. rate.
Target water leak currently under investigation.
Near and far detectors fully operational with > 90% live time.
Beam neutrinos now observed in near and far detectors.
Mary Bishai, BNL 32 – p.32/33
More info on MINOS target leak
Target is being moved into workcell
for further investigation.
Mary Bishai, BNL 33 – p.33/33