High Energy Physics Group, National Taiwan University
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Transcript of High Energy Physics Group, National Taiwan University
High Energy Physics Group, National Taiwan University
Yee Bob Hsiung National Taiwan Universityfor NuTel group
UHE UHE workshop workshopApril 23-26, 2006April 23-26, 2006
IHEP, BeijingIHEP, BeijingIntroductionFeasibility StudyDetector StatusConclusion
Status of NuTel - a Neutrino Telescope for Observing PeV from AGN
Cosmic Rays and Neutrinos - Back to 2002
Cosmic Ray Spectrum
Not Well Understood
CR + X e2e
UHECR + CMB N + GZK
~ 0.1 /EeV/year/km2/sr
GZK Firm!
~ 1.2 x 103 /PeV/year/km2/sr
AGN ?
AGN Jets, CRs and AGN Jets, CRs and Protons?
?
Window of Opportunity
Conventional Detector
UHECR Detector?
Earth SkimmingEarth Skimming
Telescope
Cross SectionCross Section ~ E~ E1.41.4
Earth Skimming + Mountain PenetratingCherenkov vs. fluorescence
Sensitive to
e: electron energy mostly absorbed in mountain : no extensive air shower
appearanceexperiment!
Three simulation stagesThree simulation stages1. Mountain simulation:
+N cross-section– inelasticity– energy loss of tau
2. Air shower simulation: Cerenkov photons decay mode – CORSIKA detailed air shower simulation vs. f
ast simulation3. Detector performance simulation
– light propagation + Q.E.– pixelization for triggers – reconstruction
1
2
3
2002-2004
inside mountaininside mountain
• SM CC +N cross-section• Inelasticity & energy loss are calculated by G.L. Lin, J.J. Tseng, T.W.
Yeh, F.F. Lee of NCTU• Range (distance when survival prob = e-1) are calculated by M.A. Huang
Tau fluxTau flux
• Tau flux:– Fast simulation: single interaction inside target– Full-scale transport eq.: Consider multiple interactions
...• Conversion efficiency:
– optimal thickness ~ several times of
– Energy loss decreases conversion efficiency
dE/dxNo dE/dx
Lateral profile of Cerenkov photonsLateral profile of Cerenkov photons for horizontal shower (CORSIKA ) for horizontal shower (CORSIKA )
• Similar profile for showers produced by e– and • Cerenkov ring distance ~ (L-Rmax)tan c
• Outside ring, photon density ~ exponential decay• Detector can trigger far away from Cerenkov ring
1018 eV
1016 eV
1014 eV
Photons numbers vs opening anglePhotons numbers vs opening angle
No atten.
Photon density
Opening angle (radian)
1 PeV showerShower core to
detector plane
30 km awaySerious drop
with attenuation Atten.=15km
Optics assumptions (back in 2003)Optics assumptions (back in 2003)• ASHRA-type Mirror + a simple correctio
n lens
• Multi-Anode Photomultiplier with 0.5o x 0.5o pixel span
• Light collection : 1 m2 aperture, 8o x 16o field of view,
over all 10% efficiency for γ→ p.e.
The Signal and Background PatternThe Signal and Background Pattern
Cherenkov: ns pulse, angular span ~ 1.5 degreesNight Sky Background (mean)
Measured at Lulin observatory: 2.0 x103 ph/ns/m2/sr
A magnitude 0 star gives 7.6 ph/m2/ns in (290,390) nm
Cosmic Ray background very smallCluster-based trigger algorithm
Random Background with NSB flux 1 km away from a 1 PeV e- shower
Trigger ConfigurationTrigger Configuration• Single Pixel Trigger: One pixel pass energy threshold H
• Duo Trigger: Two neighbouring pixels pass threshold H
• H-L Trigger: Two neighbouring pixels with one passes high threshold H
and the other one passes low threshold L• Sum Trigger: 1. (3x3) trigger cell
2. Central pixel pass high threshold H
Neighbour Npe Sum pass threshold A=n1+n2+…+n8
Night Sky Background:
• Npe Follows Poisson distribution: Prob(n;μ) = e-μ μn/n!, μ = <Npe> Φ tg A FOV εA εq ,
Φ = 200/ns/m2/sr A=1m2 FOV=0.5ox0.5oεA =0.5 εq =0.2 μ =0.039 tg=25ns ; =0.076 tg=50ns
Range<0.5km: Majority of photon arrives within 25 ns
Most of photons arrives within 50 ns
H L
H H
H
Hn2n1 n3
n4n5n6n7
n8
NSB Trigger RateNSB Trigger Rate
50nsSingle Pixel Trigger: H=6H-L Trigger : (H,L)=(6,1)Duo Trigger : H=4Sum Trigger1: (H,A)=(1,9)Sum Trigger2: (H,A)=(2,8)
25nsSingle Pixel Trigger: H=5H-L Trigger : (H,L)=(5,1)Duo Trigger : H=3Sum Trigger1: (H,A)=(1,7)Sum Trigger2: (H,A)=(2,6)
For 10 Hz order NSB trigger rate, the Trigger Configurations are:
8 Npe
10 Npe
N=107MC, (32x32)Pixels
Trigger Efficiency for Electron ShowerTrigger Efficiency for Electron Shower
Sum Trigger givesThe largest range
1.1km for trig=90%
Sum trigger are similar
Other Three triggersare similar
Conservative estimation is 200 γneeded
90%
Preliminary ReconstructionPreliminary Reconstruction• Reconstruction: Minimize 2 for x,y,,,
and E– Two Detectors Separated by ~ 100m
E, x, y, ,
1 2
N1, T1, x1 , y
1, 1, 1
N2, T2, x2 , y
2, 2, 2
Possibility for Reconstruction Possibility for Reconstruction
• Possible to Reconstruct Events – Angular Error within 1°– Energy Error ~ 40%– Reconstruction Efficiency > 90% if triggered
Acceptance DeterminationAcceptance DeterminationIntegration of efficiencies in phase space
Three independent methods for cross-checking
Results are consistent with each other!
Method Efficiency Integration Investigator
MIR Range determined fromSimulation
Monte Carlo Alfred
MIME Modelled Curve Monte Carlo Minzu
NISE Detailed Simulation Numerical Ping
All three got consistent results
Best FOV Best FOV Site Rate
(/yr)
Hualalai
88º - 96º
49º - 81º ♤ 0.71
Loa 90º - 98º
2º - 34º ♤ 0.85
Kea 92 º - 100 º
-134º - 102º ♥
1.10
♤ FOV centered on Kea♥ FOV centered on Hualalai
Note that FOV is 8o x 32 o
MIMEMIME
Loa
Big Island
contour plot
• Pick energy• Put detector on top of Loa• Pick position randomly on a 20
km by 20 km vertical plane located 25 km north of Loa
• Emit randomly in 60o cone• Trace the track to find the exit p
oint of • Find decay point• Assume e/π took away ½ of en
ergy and find the shower core position (air density 10-3 g/cm3)
• Make sure shower core is above 1.5 km cloud level
MIMEMIMEMake sure the pathway is clear between exit point and shower coreFind the angle and distance between shower core and detectorDetermine the number of photons in the solid angle covered by detector and apply attenuation effect (18 km attenuation length)Set the threshold at 200 ’s and check the shower core in the FOV (vertical -8o-0o and horizontal -4o- 12o)Event rate = 7.5 x 400 x π x 0.1(duty) x 0.8(BF) x eff The obtained rate for Loa is 0.46 per year
AcceptanceAcceptance● Mauna Loa watching
Mauna Kea● Higher energy
shower Larger trigger area, but longer decay length (50 km @ 1 EeV)
SensitivitySensitivity4.7 ×102Defined as reachable
upper limit of fluxAssume F(En) = F0 En-2
Assume no signal in 2 years of observationFeldman-Cousin method for upper limits: 2.44 signal eventsTheo1: ~ 0.5 events/year
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
Multi-anode PMT (MAPMT) “H7546” of 8x8 pixels is used as photon-sensitive device
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
Computer-controlled HV power supply “VHQ-202M” in VME is used for MAPMT, 2 channels/module, 1 channel supplies 4 MAPMT (256 pixels)
“SBS” PCIVME adapter
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
“SBS” PCIVME adapter
Signal-sharing plate is used for increasing dynamic range of the system in factor of about 10-20 times
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
16-channels charge sensitive preamplifier transforms charge into voltage for digitising by pipelined ADC
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
4 preamplifier boards and signal- sharing plate are connected to one MAPMT
Holes for mechanical purposesin future
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
32-channels Data Collection module in cPCI (PXI) processes signals from 32 channels, has Trigger logic on the module and memory of 256 ADC clocks. If one event is 8 clocks (200 ns), memory could keep up to 32 events.
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
There will be 16 DCM boards (512 channels) inside one PXI chassisDCM
System (CPU) card
Active cPCI extender for debugging
Schematics of electronicsSchematics of electronics
Trigger
Hamamatsu8x8 MPMT
16-channelspreamplifier
DAQ
PMT Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
Triggerdaisychain
cycleRAM
Signal-sharing plate
2 m cable
HV powersupply
Front-end electronics Inside cPCI (PXI) chassis
DAQ – in Linux, inside cPCI (PXI) CPU card
Some testsSome tests
Trigger
16-channelspreamplifier
DAQ
Preamp.
32 – channels Data Collection Module in cPCI
10 bit x40 MHzADC
FADC
bufferRAM
cycleRAMC
Fromgenerator
A
CCable ~20mCable ~20mCable ~20mCable ~20m
A
B
B
C
CD
D
Double pulse (~100 ns difference)Double pulse (~100 ns difference)
Telescope parametersTelescope parameters
FOV: 16o horizontally 8o vertically
Image size at FP: 24cm(H) X 12cm(V)
Aperture: 1m2
Light guide:reduces image 3:1.8
Photo sensor:8X8 MAPMTs w.512 pixelsX2for 2 telescopes
Three-fresnel surface telescopeThree-fresnel surface telescope
0*: 0.8mm, 4*: 0.8mm, 8*: 1.6mm
File = fresnel13.otx Scale = 0.1260 Y/Z-view
793.7653 mm
Front side: fresnel1.1 m
Both sides: fresnel
---: 8o
---: 4o
---: 0o
A fresnel-edge loss: 17%
Spot image of 3-fresnel telescopeSpot image of 3-fresnel telescope
SPOT DIAGRAM File = fresnel13.otx 10.00000 mm
Wavelength(micron)
0.40470
In : 788Out: 0
In : 780Out: 0
In : 772Out: 0
0.0000 0.0000/ deg 0.0000 4.0000/ deg
0.0000 8.0000/ deg
Telescope w. two-identical fresnel Telescope w. two-identical fresnel lenslens
15:29:33
Error function = 0.508347E+06 Scale: 0.12 04-Apr-06
208.33 MM
Front side: fresnel1.1 m
Back side: fresnel
Aspheric lens0.4 m
Tow fresnel lens are identical---: 8o
---: 4o
---: 0o
A fresel-edge loss: 11%
Spot image of two-identical fresnel Spot image of two-identical fresnel telescopetelescope
SPOT DIAGRAM File = fr01 10.00000 mm
Wavelength(micron)
0.38000
In : 788Out: 0
In : 780Out: 0
In : 780Out: 0
0.0000 0.0000/ deg 0.0000 4.0000/ deg
0.0000 8.0000/ deg
Light guide simulationLight guide simulation
0
0.2
0.4
0.6
0.8
1
0 20 40 60 80
incident(deg)
T
20mm 30mm 35mm 40mm 50mm
Light guideLight guide
ConclusionConclusion• NuTel is an experiment dedicated to Earth skimmin
g / mountaing watching• The PeV cosmic rate is ~ 1 event/year• The cost is low: O(1) million US dollars to build it• Very good project for training students• However, lack of funding support in last two years• Ceased collaboration with ASHRA last year• Look for new funding support from university this s
pring, if succeed will start the optics this summer• Schedule: prototype deployment in ~2007-2008 for initial observation
People who worked on NuTel beforePeople who worked on NuTel before• Italy: IASF, CNR, Palermo
– N. La Barbera, O. Catalano,G. Cusumano, T. Mineo,B. Sacco
• France: Paris, France F. Vannucci, S. Bouaissi
• USA: Hawaii J.G. Learned
• Japan: ICRR M. Sasaki
• Taiwan: – NCTS/CosPA3– G.L. Lin, H. Athar
(Faculty)
NTUHEP/CosPA2PIs: W.S. Hou & Y.B. HsiungHardware Team:
K. Ueno (Optics)Y.K. Chi (Electronics)Y.S. Velikzhanin (Electronics)J.G.Shiu (DAQ)M.W.C. Lin (Technician)Master students
Simulation Team:M.Z. Wang (Faculty)P. Yeh (Faculty)C.C. Hsu (Ph.D. student)
master studentsNUU
M.A. Huang + students (Faculty)
From 2002-2005