Download - Moscow, 18.10.2005
Moscow, 18.10.2005Moscow, 18.10.2005
V. Aynutdinov, INR RASV. Aynutdinov, INR RASfor Baikal collaborationfor Baikal collaboration
The Baikal neutrino telescope:The Baikal neutrino telescope: Physics results and future plansPhysics results and future plans
Institute for Nuclear Research, Moscow, Russia. Irkutsk State University, Russia. Skobeltsyn Institute of Nuclear Physics MSU, Moscow, Russia. DESY-Zeuthen, Zeuthen, Germany. Joint Institute for Nuclear Research, Dubna, Russia. Nizhny Novgorod State Technical University, Russia. St.Petersburg State Marine University, Russia. Kurchatov Institute, Moscow, Russia.
CollaborationCollaboration
BAIKAL in BAIKAL in CernCourier 7/8-CernCourier 7/8-20052005
A
Amanda/IceCube
Baikal
N NNeutrino telescope NT200 (1998) Design Physics Results (selected) : NT200 upgrade -> NT200+ (2005) New Design Calibration (new laser)Perspectives: Gton scale detector (GVD) at Baikal NT200+ as a basic cell of future Gton detectorSummary Motivation Present telescope configuration is perfect test facility for future Gton detector
Outline:
Shore station
4000 m
1366 m
The SiteThe Site
1070 m depthAbsorption length: 20-30 mScattering length: 30-70 mIce as a natural deployment platform
51 d 45’’ 59’ N51 d 45’’ 59’ N104 d 25’ 09’’ E104 d 25’ 09’’ E
Ice as a natural deployment platform
• Ice stable for 6-8 weeks/year: – Maintenance & upgrades – Test & installation of new equipment
BaikalBaikal
Abs. Length: 22 ± 2 m Scatt. Length (geom) ~ 30-50 m cos ~ 0.85-0.9
Baikal - Optical Properties
Open configuration of the Telescope and good water parameters of Baikal waterOpen configuration of the Telescope and good water parameters of Baikal water allow to observe big water volume much more than geometrical boundariesallow to observe big water volume much more than geometrical boundaries
Example of interaction between ANTARES,NEMO Baikal
Verification of Lake Baikal Attenuation / Absorb. / Scatt. results
Cross-Calibration: AC9 (Antares/Nemo) vs. Burhan ASP15
Baikal-NEMO Campaign March, 2001
see: NIM A498 (2003)
1998: NT200192 OM at 8 strings 1 Mton at 1 PeV
1996 NT96 96 OM at 4strings
2005: NT200+228 OM at 8 + 3 strings 10 Mton at 10 PeV
Project Milestones1991 Project NT200 approved 1993 NT36
36 OM at 3 strings The first underwater array operatesFirst ’s and ’s in Neutrino Telescope
-8 strings: 72m height - 192 optical modules 96 measuring channels T, Q measure *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, Vgeo=105m3=
0.1Mton
Selected ResultsNT200
Low energy phenomena (muons) - Atmospheric neutrinos - WIMP neutrinos High energy phenomena (cascades) - DDiffuse neutrino fluxiffuse neutrino flux - Neutrinos from GRB - Prompt muons and neutrinos - Exotic HE muons Search for exotic particles - Magnetic monopoles
Atmospheric Neutrinos
372 Neutrinos in 1038 Days (1998-2003)
Skyplot (equatorial coordinates) Skyplot (equatorial coordinates) of neutrino eventsof neutrino events
EETHRTHR 15-20 GeV 15-20 GeV Important calibration tool
WIMP Search
+ b + b
C + +
Search of nearly vertically upwardSearch of nearly vertically upwardgoing muons , exceeding the flux of going muons , exceeding the flux of
atmospheric neutrinosatmospheric neutrinos
Limits on the excess muon flux from theLimits on the excess muon flux from the centre of the Earth as a function of WIMP masscentre of the Earth as a function of WIMP mass
Angular distribution of selected neutrinoAngular distribution of selected neutrinocandidates as well as background expectation candidates as well as background expectation
Physics topics:- HE cascades from e - NC/CC
* Diffuse astroph.flux * GRB correlated flux
- HE atmospheric muons * Prompt * Exotic
NT-200 is used to watch the volume below for cascades.
(„BG“)
NT-200
large effective volume
Search for High Energy CascadesLook for upward moving light fronts.
Signal: isolated cascades from neutrino interactions
Background :Bremsshowers fromh.e. downward muons
Final rejection of backgroundby „energy cut“ (Nhit)
tmin > -10nsNhit > 15 ch.
Hit channel multiplicity(experiment and background
expectation)
Diffuse Neutrino Flux
atm
2.5
1.5
2
Shape of signal in Nhit distribution for = A E- (=1.5, 2.0, 2.5).
NT200 (1038 days)
DIFFUSE NEUTRINO FLUX(Ф ~ E-2, 10 TeV < E < 104 TeV)e(AGN)e(Earth)Ф(e))
<8.1 ·10-7 GeV cm-2 s-1 sr-1
W-RESONANCE ( e )( E = 6.3 PeV, 5.3 ·10-31 cm2 )Фe < 3.3 · 10-20 (cm2 · s · sr · GeV )-1
~
Experimental limits + bounds/ predictions
Models already ruled out by the experimentsSS - Stecker, Salamon96 (Quasar)SeSi - Semikoz, Sigl (Models/Expts. are rescaled for 3 flavours)
Diffuse Flux Limits + Models
New configuration NT200+
140 m
100m
36 additional PMTs on 3 far ‘strings‘ 4 times better sensitivity Improve cascade reconstruction
Vgeom ~ 4 ·106 m3
Eff. shower volume: 104TeV ~ 10 MtonExpected -sensitivity (3 yrs NT200+) : E2 ФV < 0.9 · 10-7 GeV cm-2 s-1 sr-1
NT200+ as test facility for Gton scale detector1. Optical module 2. Calibration system3. New electronics 4. Data acquisition system5. Time synchronization 6. Cable communications
NT200+ commisioned April 2005 1. 3 outer strings were instaled1. 3 outer strings were instaled
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 system Synchronization system ** time synchronization time synchronization NT200 <-> outer NT200 <-> outer
stringsstrings ** event clusterisation event clusterisation
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
Shore Center
M odem line
D E M D E MC E M
S C M CON TROL
Trig NT200
String trigger
Un derw ater PC
S tr# 7S tr# 2 S tr# 8
S tr# 3 S tr# 4
N T -200
S tr# 1
S tr# 2
N T +
ControlNT+
ControlNT200
TDC
Sto
p
Tri g
Re q
, Da t
a
S tr# 6S tr# 1
S tr# 5
S C M
S tr# 3
Ethernet
CONTROL
TrigReqString time
Data NT200Data NT+
Trig
NT+
Dat
a
TDC Stop
DAQ and control system of NT200+
Two subsystems: NT200 and NT+
Two-level time measurement and dataacquisition systems:
Low level: - Strings: PMT time and amplitude measurements; - DEM: trigger and event clusterisation systems - SEM: slow control
DAQ Center
- 2 underwater PC connected to shore; - CEM: trigger time measurement
PC104: Advantech-PCM9340
DSL-M: DSL-modem FlexDSL-PAM-SAN with hub and router, 2 Mbit/s.
SwRSTP: a managed Ethernet switch RS2-4R
CSrv: WUT-58211, for PC-terminal emulation
Mc: two media-converters for coaxial connection
D-Mod, C-Mod: experiment data and control modems
Underwater PCs
New Laser 100m
100m
X2X1
X3
100m
Laser is visible >200m with high Ampl. (NT and ext.strings)
Laser intensity : cascade energy:(1012 – 5 1013 ) : (10 – 500) PeV
RMS of arrival time distribution: ~ 2 ns
tt11
tt22
tt1212
5 series of Laser pulses5 series of Laser pulses
NT200+ time resolutionNT200+ time resolutiont = tt = t11+ t+ t12 12 – t– t22
tt11, , tt22 - PMT jitter and light scattering - PMT jitter and light scattering
tt1212) ) 2 ns - electronics jitter 2 ns - electronics jitter
1 10 1000
2
4
6
8
10
, n
s
Np.e.
Light scatteringLight scattering- scattering length 30 m- scattering length 30 m- distance to Laser ~200 m- distance to Laser ~200 m
Jitter of electonics ~2 nsJitter of electonics ~2 ns- synchro cable length 1.2 km - synchro cable length 1.2 km - TDC bin 2 ns- TDC bin 2 ns
The amplitude dependence of relative time jitter measured for several pairs of channels of NT200 andexternal string. Red line is result of calculations
Reconstructed vs. simulated Reconstructed vs. simulated coordinatescoordinates
of cascades in NT200+ (blue) andof cascades in NT200+ (blue) and NT200 (red)NT200 (red)
NT200+ efficiency of cascade reconstructionLaser coordinates reconstruction
NT200
NT200+
3 extern. str.
r < 1 m
NT200+ as a subunit of a Gton scale detector
For High Energy Cascades:A single string replacing theNT200 central core reduces Veff less than x3 for E>100TeV.
12 OMs strings as a subunit for a Gton scale detector = ok.
Effective volume withEffective volume with
A future Gigaton (km3) Detector in Lake Baikal.
Sparse instrumentation:
91 strings with 12/16 OM = 1308 OMs (NT200 = 192 OMs)
effective volume for 100 TeV cascades ~ 0.5 -1.0 km³
muon threshold between 10 and 100 TeV
Gton detector at Baikal lakeGton detector at Baikal lake
1. Optical module: PMT selection 2. Detector configuration: PMT location, string
configuration, distances, …
3. Electronics: flash ADC, trigger conditions, …
4. Communications: optical cables, connectors, …
5. Data acquisition system, time synchronization
R&D on the basis of NT-200+ configurationR&D on the basis of NT-200+ configuration
CONCLUSIONCONCLUSION1. BAIKAL1. BAIKAL lake experiment lake experiment running since 12 years - Diffuse Neutrino flux limit - Limit on an excess flux due to WIMP annihilation in the Earth - Limit on the flux of fast magnetic monopoles
2. NEW configuration NT200+ start of operation April 2005 - NT200+ is tailored for diffuse cosmic neutrinos Veff ~ 10 Mton at 10PeV Expected -sensitivity (3 yrs NT200+) : E2 Фv < 10-7 GeV cm-2 s-1 sr-1
- NT200+ gives good possibilities to optimise the structure and to investigate the basic elements of future Gton scale detector
3. 3. R&D Gigaton Volume Detector (km3) at Baikal lake was started
Relativistic magnetic Monopole
Cherenkov-Light n2·(g/e)2
n = 1.33
(g/e) = 137/ 2
8300
Flu
x up
per l
imit
(cm
-2 s
-1 s
r-1)
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 +
Run #3(com _ev #1395)NT-200 9 сhanNT+ 6 chan
NT200+ Start of operation April 2005 13 Apr - 23 May 2005 - Exposition time: 640 hours - Events number : 7.6 104
- More than 1 outer string: 20 events
Examples of events
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 +
Run #3(com _ev #1395)NT-200 9 сhanNT+ 6 chan
NT200+ Start of operation April 2005 13 Apr - 23 May 2005 - Exposition time: 640 hours - Events number : 7.6 104
- More than 1 outer string: 20 events
Examples of events
New Laser: Design• Isotropizer: - Glass bulb filled with “MicroGlassSpheres” (S32 from 3M; 20-70um dia.) mixed with OpticalGel A “LaserBall” similar to the SNO calibration device. - Total loss is low: 12% - 25% only !
calibrated with “Ulbricht Sphere” (1.5m diam.)
• Absolute Laser–Calibration (with commercial Laser-PowerMeter) to optimize yield also at the lake (monitor laser vs. years)
• Expect >10^12 photons/pulse