gigaton volume detector in lake baikal: status of the project zh.-a. dzhilkibaev (inr, moscow)...
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Gigaton Volume Detectorin Lake Baikal: status of the
project
Zh.-A. Dzhilkibaev (INR, Moscow)Zh.-A. Dzhilkibaev (INR, Moscow) for the Baikal Collaborationfor the Baikal Collaboration
QUARKS-2010, Kolomna, 6-12 June, 2010
1. Institute for Nuclear Research, Moscow, Russia.
2. Irkutsk State University, 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, Russia.
7. St.Petersburg State Marine University, Russia.
8. Kurchatov Institute, Moscow, Russia.
Telescope (E,)
input
water, ice Physics (E,)
Targetmuon ()
cascade(e)
output
muon cascade
E,
muons (long tracks) - ~ 0.3o – 1o, ~ 0.3logE cascades – > 30o (ice); ~ 3o – 6o (water) !
Cherenkov radiation
cascades
muon
Absorption
Scattering
Detection Principle – M. Markov 1960
energy, direction resolution
Ls < 3 m
Ls ~ 30-50 m
42o
A
NT200+/Baikal-GVD (~2017)
N N
KM3NeT(~2017)
Amanda/IceCube/IceCube(~2011)(~2011)
ANTARES
73 Strings in operation
Precursors of km3-scale neutrino telescopes: NT200 AMANDA ANTARES (Baikal) (South Pole) (Mediterranean Sea) Results:
Astrophysics HE-neutrinos
WIMPs in the Sun & the Earth
Neutrinos from GRB
Atm. neutrino flux
Magnetic monopoles etc.
Obtained results prove the detection principle and motivate the requirements of km3-scale facilities
IceCube(South Pole)
GVD(Lake Baikal)
KM3NeT(Mediterranean Sea)
MACRO
Limits on all flavor HE neutrino flux
IceCube (South Pole)
4800 Optical Modules80 Strings1500-2500 m depth ~1 km3 instrumented volume
Ice-Top – shower detection
Deep Core – low-energy neutrinos6 additional strings with dense OM spacing
2009-2010 yr.
73 + 6(Deep Core) – installed
IceCube will be completed in 2011/2012
2006-2007:
13 Strings
2005-2006:
8 Strings
2004-2005 :
1 String
2007-2008:18 Strings
1450 m
2450 m
2008-2009:
18+1 Strings
KM3NeT (Mediterranean Sea – TDR 2010)
8-inch PMT 31 3-inch PMTsOptical Module ?Research Infrastructure
Detection Unit (DU) ?Buoy
OM
OM
OM
OM
OM
Slender String 300 DU
SITE ?
Flexible tower 127 DU
Next Steps and Timeline
Next steps: Prototyping and design decisions- organised in Preparatory Phase framework- final decisions require site selection- expected to be achieved in ~18 months
Timeline:
CDR:TDR:
Mar
201
2
Design decision
Construction
2013
2017
2011
Data taking
2015
4км from the shore
1366 м depth
Shore Station
Location of the BAIKAL neutrino telescope
Location: - Northern hemisphere – GC (~18h/day) and Galactic Plane survey
- Flat 1350 m depth Lake bed (>3 km from the shore) – allows ~ 30 km3 Instr. Volume!
Strong ice cover during ~2 months:- Telescope installation, maintenance, upgrade and rearrangement
- Installation & test of a new equipment
- All connections are done on dry
- Fast shore cable installation (3-4 days)
Water optical properties:- Absorption length – 22-24 m
- Scattering length – 30-50 m
- Moderately low background in fresh water
Water properties allow detection of all flavor neutrinos with high direction-energy resolution!
Site properties
ice slot
cable
tractor with ice cutter
cable layer
Shore cable deployment
Since 1980 Site tests and early R&D started
1990 Technical Design Report NT200
1993 1993 NT36NT36 started: - the first underwater array - the first neutrino events.
1998 1998 NT200 commissioned:NT200 commissioned: start full physics program.
2005 NT200+ commissioned (NT200 & 3 outer strings).NT200+ commissioned (NT200 & 3 outer strings).
2006 Start R&D toward the Gigaton Volume Detector (GVD)
2008 2008 In-situ test of GVD electronics: 6 new technology optical In-situ test of GVD electronics: 6 new technology optical modulesmodules
2009-10 2009-10 Prototype strings for GVDPrototype strings for GVD
2010-112010-11 GVD cluster (3 strings), Technical Design ReportGVD cluster (3 strings), Technical Design Report
NT200: 8 strings (192 optical modules )Height x = 70m x 40m, Vinst=105m3
Effective area: 1 TeV~2000m² Eff. shower volume: 10 TeV~ 0.2 Mton
Quasar photodetect
or (=37cm)
NT200+ = NT200 + 3 outer strings (36 optical modules)Height x = 210m x 200m, Vinst = 5106m3
Eff. shower volume: 104 TeV ~ 10 Mton
Status of NT200+
LAKE BAIK
AL
~ 3.6 km to shore, 1070 m depth
NT200+ is operating now in Lake Baikal (~10 months/yr. persistent data taking)
Gigaton Volume Detector (GVD) in Lake BaikalR&D status
Objectives:
- km3-scale 3D-array of photodetectors - flexible structure allowing an upgrade and/or a rearrangement of the main building blocks (clusters) - high sensitivity and resolution of neutrino energy, direction and flavor content
Central Physics Goals: - Investigate Galactic and extragalactic neutrino “point sources” in energy range > 10 TeV - Diffuse neutrino flux – energy spectrum, local and global anisotropy, flavor content - Transient sources (GRB, …)
Claster Str. section
315
- 460
m
GVD - Preliminary design
Layout:
~2300 Optical Modules, 96 Strings, 12 Clusters String comprises 24 OMs, which are combined in 2 independent SectionsCluster contains 8 strings
Instrumented volume: 0.4 – 0.6 km3
Detection Performance
Cascades: (E>100 TeV): Veff ~0.3–0.8 km3
δ(lgE) ~0.1, δθmed~ 3o-6o
Muons: (E>10 TeV): Seff ~ 0.2 – 0.5 km2
δθmed~ 0.3o-0.5o
Cable communication to shore
• 1370 m maximum depth • Distance to shore 4 … 5
km• 12 clusters × 192 OM• 12 cables ~ 6 km
GVD cluster
12 Shore cables
~6 km
1350…1370 m
Shore Center
12 GVD clusters
NT200+
Optimisation of GVD configuration (preliminary)
Parameters for optimization:Z – vertical distance between OMR – distance between string and cluster centreH – distance between cluster centres
Muon effective area
R=80 m
R=100 m
R=60 m
The compromise between cascade detection volume and muon effective area:
H=300 mR = 60 mZ = 15 m
Trigger: coincidences of any neighbouring OM on string (thresholds 0.5&3p.e.)
PMT: R7081HQE,10”, QE~0.35
GVD – R&D (2006-2010)
GVD - Key Elements and Systems:
- Optical Module- FADC-readout system- Section Trigger Logics - Calibration- Data Transport- Cluster Trigger System, DAQ - Data Transport to Shore
OM
12 OMs 2 Sections 8 Strings to Shore
Section String Cluster
Optical module
XP1807(12”), R8055(13”), R7081HQE(10”)
QE ~0.24 QE ~0.2
QE~0.35
HV unit: SHV12-2.0K,TracoPowerOM controllerAmplifier: Kamp = 10LED calibration system (2 LEDs)
Functional scheme of the optical module electronics
XP1807 R8055 R7081HQE
2008-2009 20102008-2010
0 1 2 3 4 5 60,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
XP1807 #1026
XP1807 #1006 R8055
#186 R8055 #314
R8055 #228
Rel
ativ
e P
M s
ensi
tiviti
es
PMT number
Relative sensitivities of large area PMs R8055/13” and
XP1807/12”
Measuring channels
BEGPMT1
Amplifier
FADC 1 90 m coax.cable
OM
PMT12
Amplifier
FADC 12
90 m coax. cable
…
BEG (FADC Unit) -3 FADC-board: 4-channel, 12 bit, 200 MHz;-OM power controller;-VME controller: trigger logic, data readout from FADC, connection via local Ethernet
Section – basic detection unitSection:
- 12 Optical Modules - BEG with 12 FADC channels and trigger unit- Service Module (SM): LEDs for OM calibration, OM power supply, acoustic positioning system.Basic trigger: coincidences of nearby OM (threch. ~0.5&3 p.e.) expected count rate < 100 HzCommunications: BEG cluster centre: DSL-modem, expected dataflow < 1Mbit/sBEG OMs: RS-485 Bus (slow control)
Cluster DAQ center
Cluster of strings
8 Strings
String consists of 2 sections
(2×12 OM)
Cluster DAQ Centre (4 modules)1.PC-module with optical Ethernet communication to shore (data transmission and synchronization) 2.Trigger module with 8 FADC channels (time mark of string trigger)3.Data communication module (8 DSL-modems for communication to strings, ~10 Mbit/s for 1 km )4.Power control system
In-situ tests of basic elements of GVD with
prototypes strings (2009...2010)
Investigation and tests of new optical modules, DAQ system, cabling system, triggering approaches
( LED Laser Muons)
NT200+
Prototype string 2009
Prototype string 2010
PMT: Photonis XP1807 6 OM Hamamatsu R8055
6 OM
PMT: Hamamat
su R7081HQ
E7 OM
Hamamatsu R8055
3 OM
GVD prototype strings 2009 - 2010
R7081HQE
R8055
Prototype string deployment: April 2010
PC BEG1
SM
BEG2
Time resolution of measuring channels (in-situ tests with LED)
LED flasher produces pairs of delayed pulses. Light pulses are transmitted to each optical module (channel) via individual optical fibers. Delay values are calculated from the FADC data.
0 2 4 6 8 10 12
492
496
500
504
508 Expected dT = 497.5
dTLE
D ,
ns
# Channel
Measured delay dT between two LED pulses
0 2 4 6 8 10 120
50
100
150
200 A (LED1) p.e. A (LED2) p.e.
A, p.e.
#Channel
LED1 and LED 2 pulse amplitude
Example of a two-pulse LED flasher event (channel
#5)
LED1
LED2
(dT) 1.6 ns
Time accuracy (in-situ test with Laser)
LASER
11
0 m
OM#7OM#8
OM#9
OM#10
OM#11
OM#12
OM#1OM#2
OM#3
OM#4
OM#5
OM#6
97 m
r1
r2
10 20 30 40 50-8
-6
-4
-2
0
2
4
6
8
dTLA
SE
R
- dT
GE
OM
, n
s
dR, m
Differences between dT measured with Laser and
expected dT in dependence on distances between
channels dr
T < 3 ns
Test with LASER
T = <dTLASER – dTEXPECTED>
dTEXPECTED = (r2-r1)cwater
dTLASER - time difference
between two channels measured for Laser pulses (averaged on all channel
combinations with fixed (r2-
r1))
Distribution of time difference T between muon pulses for two up-ward looking PMTs:
experiment and expectation from atm. muons.
T between muon pulses
detected with different
channels are studied and
compared with simulation of
the string response to the
atmospheric muon flux.
Trigger: 3-fold OM
coincidences
Muon detection
MC
Schedule:
>2006 Activity towards the Gigaton Volume Detector
2008-10 Prototype Strings ( test of GVD key elements and systems)
2010-11 Technical Design Report
2010-12 Preparatory Phase, Prototype of Cluster (in-situ test) 2011-16 Fabrication (OMs, cables, connectors,
electronics)
2012-17 Construction (0.2 0.4 0.6 0.8 1.0) GVD