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Lake Baikal Neutrino Experiment
Present and FutureG.V.Domogatsky (INR, Moscow)
for the Baikal collaboration
1. Institute for Nuclear Research, Moscow, Russia.
2. Irkutsk State University, Irkutsk, Russia.
3. Skobeltsyn Institute of Nuclear Physics MSU, Moscow, Russia.
4. DESY-Zeuthen, Zeuthen, Germany.
5. Joint Institute for Nuclear Research, Dubna, Russia.
6. Nizhny Novgorod State Technical University, Nizhny Novgorod,
Russia.
7. St.Petersburg State Marine University, St.Petersburg, Russia.
8. Kurchatov Institute, Moscow, Russia.
The Baikal Collaboration
4km OffShore
Depth: 1366 m
Shore Station
1366m Depth
Neutrino Telescope NT200+ (April, 2005)
6
The NT-200 Telescope-8 strings: 72m height - 192 optical modules- pairwise coincidence 96 space points- calibration with N-lasers- timing ~ 1 nsec- Dyn. Range ~ 1000 pe
Effective area: 1 TeV ~2000 m² Eff. shower volume: 10TeV ~0.2Mt
Quasar PMT: d = 37cmHeight x = 70m x 40m, V=105m3
Installation 1993-1998
CampIce as a natural deployment platform
~ 2 months
NANP’03NANP’03
GOALSGOALS
Natural flux of neutrinos with energy Natural flux of neutrinos with energy E> E>1515GeVGeV ( (search for point sources search for point sources of neutrinosof neutrinos))
WIMPWIMP Magnetic MonopolesMagnetic Monopoles Diffuse flux of very high energy Diffuse flux of very high energy
(E>10 TeV) neutrinos(E>10 TeV) neutrinos
Neutrino events from low hemisphere
April 1998 - February 2003 , 1038 d, 372 events.
Atmospheric Muon-Neutrinos
- With looser cuts, 1998-2002: 372 events. N(>15GeV)/N(>1GeV)~1/7 A higher statistics neutrino sample for Point-Source Search.- MC: 385 ev. Expected (15%BG).
Skyplot (galactic coordinates)
E_thr ~ 15GeVE_thr ~ 15GeV
Search for fast monopoles (
N= n2 (g/e)2 N = = 8300 N g = 137/2, n = 1.33 ~E=107 GeV
Event selection criteria:
hit channel multiplicity - Nhi t> 35 ch,upward-going monopole -(zi-z)(ti-t)/(tz) > 0.45 & o
Background - atmospheric muons
90% C.L. upper limit on the flux of fast monopole (994 livedays)
19
Search for High Energy -CascadesNT-200
large effective volume
Look for upward moving light fronts.
Signal: isolated cascades from neutrino interactions
Background:Bremsshowers fromh.e. downward muons
Final rejection of backgroundby „energy cut“ (Nchannel)
(BG)
Baikal
Baikal
Absorbtion Length: 22 ± 2 m Scattering Length ~ 30-50 m cos ~ 0.85-0.9
Optical properties
Fiducial volume
Vg(NT-200)
AMANDA II
Position of cascade vertex
Neutrino Energy, lg(E/ТeV)
UPPER LIMITS ON THE DIFFUSE NEUTRINO FLUX
(theoretical and experimental)
НТ-200+
км3
NT200+ commissioned April 2005 1. 3 outer strings were 1. 3 outer strings were
installedinstalled
2. New DAQ – final 2. New DAQ – final modernization modernization
-- 2 Underwater PC with Flex 2 Underwater PC with Flex DSL modem (1 Mbod),DSL modem (1 Mbod),
Underwater Ethernet Underwater Ethernet -- Synchronization unit Synchronization unit ** time synchronization time synchronization NT200 <-> outer NT200 <-> outer
stringsstrings ** event clusterization event clusterization
3. New Software 3. New Software DOS DOS --> Linux, Remote > Linux, Remote
controlcontrol
4. New 2 cables to shore (2x4 4. New 2 cables to shore (2x4 km)km)
5. Calibration - New bright 5. Calibration - New bright LaserLaser
1 10 100 1000 PeV
4 15 23 40 Mton
NT200+
Cascade coordinates (energy) reconstruction efficiency
NT - 200+
NT200+ time synchronization (new laser)
mm
Time differences NT200 – outer
string:2-4nsec fwhm
interstring/NT200 jitter>10>101212 photons/pulsephotons/pulse
8
1
2 4
7
3
3 +
2 +1 +
Ru n #42 (com _ev #1270)NT-200 22 сhanNT+ 7 chan
6
5
8
15
2 4
6 7
3
3 +
2 +1 +
Ru n #3(com _ev #1395)NT-200 9 сhanNT+ 6 chan
NT200+ Start of operation April 2005
Examples of events
NT200+ as a module of Gigaton (km3) Detector in
Lake Baikal
NT200+ as a module of Gigaton (km3) Detector in
Lake Baikal
A Gigaton (km3) Detector in Lake
Baikal.
Sparse instrumentation:
91 strings with 12 OM = 1308 OMs
effective volume for 100 TeV cascades ~ 0.5 -1.0 km³
muon threshold between 10 and 100 TeV
624m
280m
70m
70m
120m
208m
Baikal – GVDBaikal – GVDSchedule MilestonesSchedule Milestones
06-07 R&D, Testing NT200+06-07 R&D, Testing NT200+ 08 Technical Design08 Technical Design 08-14 Fabrication (OMs, cables, 08-14 Fabrication (OMs, cables,
connectors, electronics) connectors, electronics)
10-12 Deployment (0.1 – 0.3) km310-12 Deployment (0.1 – 0.3) km3 13-14 Deployment (0.3 – 0.6) km313-14 Deployment (0.3 – 0.6) km3 15-16 Deployment (0.6 – 0.9) km315-16 Deployment (0.6 – 0.9) km3
Overall cost with logistics ~ 20 MEuro Detector ~ 16 MEuro Logistics, including infrastructure ~ 4
MEuro
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