Calibration of
TA Fluorescence Detector
IKEDA Daisuke
ICRR, University of Tokyo
( JSPS fellow )
Contents
•Current status of TA
•FD calibration
Telescope Array Collaboration
R.U.Abbasi25,T.Abu-Zayyad25,R.Azuma21,J.W.Belz25,D.R.Bergaman19,S.A.Blake25,O.Brusova25,R.Cady25,
Z.Cao25,B.G.Cheon6,J.Chiba22,M.Chikawa11,I.S.Cho28,W.R.Cho28,E.J.Cho6,F.Cohen8,K.Doura11,
T.Doyle26,T.Fujii17,H.Fujii9,T.Fukuda21,M.Fukushima8,Y.Hayashi17,K.Hayashi21,N.Hayashida8,
K.Hibino10,K.Honda27,P.Huenitemeyer13,G.A.Hughes19,D.Ikeda8,N.Inoue20,T.Ishii27,S.Iwamoto27,
C.C.H.Jui25,K.Kadota15,F.Kakimoto21,H.S.Kang18,K.Kasahara1,H.Kawai2,S.Kawaka20,S.Kawakami17,
E.Kido8,H.B.Kim6,J.H.Kim6,A.Kitsugi8,K.Kobayashi22,Y.Kondo8,Y.Kwon28,J.H.Lim18,K.Martens25,
T.Matsuda9,T.Matsuyama17,J.A.J.Matthews24,J.N.Matthews25,M.Mimamino17,K.Miyata22,H.Miyauchi17,
M.Mostafa25,T.Nakamura12,S.W.Nam5,T.Nonaka8,S.Ogio17,S.Oh5,M.Ohnishi8,H.Ohoka8,A.Ohshima17,
T.Okuda17,J.Ormes23,S.Ozawa1,I.H.Park5,D.Rodriguez25,S.Y.Roh3,D.S,Ryu3,H.Sagawa8,N.Sakurai8,
L.M.Scott19,T.Shibata8,H.Shimodaira8,J.D.Smith25,P.Sokolsky25,R.W.Springer25,S.R.Stratton19,
G.Sunnis13,S.Suzuki9,M.Takeda8,A.Taketa8,M.Takita8,Y.Tameda21,H.Tanaka17,K.Tanaka7,M.Tanaka9,
M.J.Taylor26,M.Teshima14,J.R.Thomas25,S.B.Thomas25,G.B.Thomson19,H.Tokuno8,T.Tomida27,R.Torii8,
Y.Tsunesada21,Y.Tsuyuguchi27,Y.Uchihori16,S.Udo1,H.Ukai27,Y.Wada20,V.B.Wickwar26,L.R.Wiencke25,
T.D.Wilkerson26,T.Yamakawa8,Y.Yamakawa8,H.Yamaoka9,J.Yang5,S.Yoshida2,H.Yoshii4
(1) Advanced Research Institute for Science and Engineering, Waseda University
(2) Chiba University
(3) Chungnam National University
(16) National Institute of Radiological Sciences
(4) Ehime University
(17) Osaka City University
(5) Ewha Womans University
(18) Pusan National University
(6) Hanyang University
(19) Rutgers University (20) Saitama University
(7) Hiroshinma City University
(21) Tokyo Institute of Technology
(8) Institute for Cosmic Ray Research, University of Tokyo
(22) Tokyo University of Science
(9) Institute of Particle and Nuclear Studies, KEK
(23) University of Denver
(10) Kanagawa University
(24) University of New Mexico
(11) Kinki University
(25) University of Utah
(12) Kochi University
(26) Utah State University
(13) Los Alamos National Laboratory
(27) Yamanashi University
(14) Max-Planck-Institute for Physics,
(28) Yonsei University
(15) Musashi Institute of Technology
(29) Institute for Nuclear Research of Russian Academy of Science
～30 institutes from
Japan, USA, Korea,
and Russia
Telescope Array Experiment
FD (HiRes)
~1400m a.s.l.
31km
FD
SD
•Desert in Utah ,USA
•3 stations of
Fluorescence Detector
•507 Surface Detectors
•Full operation was
started at Mar/2008
Fluorescence Detector
Fluorescence Detector
12telescopes / 1station
F.O.V. :3-18°×18°
256PMTs/camera
1021mm
893mm
3300mm
F.O.V. :17.7-33°×18°
PMT:
HAMAMATSU
R9508
60mm
Middle Drum station (HiRes-1)
FD current status
Observation time of BRM (~ 5/Jan/2009)
1417 hours
Test
Observation
Observation (LR 6/12
(BRM)
telescope)
Full Operation
of 3 station
FD -example of eventsummation of waveforms
Surface Detector
Surface Detector
Plastic scintillator (AGASA-type)
3m2, 1.2cm, 2layer
Wireless LAN 2.4Ghz
1.2km spacing
FADC 12bit 50MHz
120W Solar panel
GPS
SD current status
Live time
Add boundary trigger
BR
SK
SK
LR
Observation as
three divided arrays
(504 SD)
Full Operation
as one large array
(507 SD)
LR
BR
SD monitoring
Every second
•
•
•
# of clock pulse between each 1 PPS from
GPS
Time stamp of GPS
# of trigger above 3 MIP.
Every minute
•
•
•
•
•
# of trigger above 0.3 MIP
Battery voltage, charge current
Solar panel output voltage
Temperatures of SD equipments
Humidity in the detector box
Every 10 minutes
•
•
•
Histograms of 1MIP & pedestal distributions
Histograms to check PMT linearity
# of satellites used by GPS.
Anti-correlation
Characteristics of TA
As a hybrid detector
▌ SD
►AGASA-type plastic scintillator
►Energy can be determined as independent of FD
▌ FD
►HiRes-1 was moved as one of the TA FD station.
►Absolute calibration by using Electron beam accelerator
(TA-LINAC)
▌ The disagreement of AGASA and HiRes can be tested
directly.
▌ Fine energy measurement as direct determination by SD, FD
with TA-LINAC, and comparison in hybrid event.
FD Calibration
Main items of FD Calibration
▌ Telescope
►Absolute gain (photon-to-FADC) measurement by
CRAYS
►Relative gain monitor by Xe and YAP
►On-site uniformity scanner
►Mirror reflectance measurement
▌ Atmospheric
►LIDAR
►Cloud monitor
▌ End-to-end
►CLF
►TA-LINAC
The preparation of 1st data set of FD
calibration for telescope is almost
finished.
PMT Calibration - absolute gainCRAYS
Peak: 0.5075
count/photon(337.1nm)
•Absolute PMT gain measurement Using N2
laser Rayleigh scattering in N2 gas.
•The absolute gain (photon-to-FADC) of 2 or
3 PMTs in one camera are measured and
adjusted by CRAYS.
~1%
N2 Laser
PMT Calibration –relative gainYAP pulser
YAP pulsers are installed on the standard PMTs calibrated
by CRAYS.
2 or 3 PMTs with YAP are installed in each camera.
YAP is stable light source for gain monitoring.
YAP (YAlO3:Ce+241Am)
Peak 365nm
50Hz～100Hz
Xe flusher
The gain adjustment and
relative gain monitoring is
done by Xe flusher.
This measurement is done
every 1 hour on observation
time.
Result of gain adjustment
All HV is 850V
After adjustment
~1%
PMT Calibration
-temperature characteristics of PMT and YAPIncubator(-10~40degree)
#5
Optical
fibers
YAP
Stable room temp.
(T±0.5℃)
PMT
#1
Function gen.
#4
UV-LED
#3
Splitter
#0
#2
Dark box
Patch panel
Signal Digitizer/Finder
18
Temperature Coefficients
of PMTs with pre-amplifier
%/℃
－0.4
%/℃
#2
－0.4
%/℃
#3
%/℃
－0.4
#4
－0.4
－0.5
－0.5
－0.5
－0.5
－0.6
－0.6
－0.6
－0.6
－0.7
－0.7
－0.7
－0.7
－0.8
－0.8
－0.8
－0.8
－10
0 10 20 30 [℃]－10
%/℃
%/℃
－0.4
#6
－0.4
Average0 10 20 30 [℃]－10
0 10 20 30 [℃]－10
%/℃
~ -0.65
%/deg
#7
－0.4
#8
－0.4
－0.5
－0.5
－0.5
－0.6
－0.6
－0.6
－0.6
－0.7
－0.7
－0.7
－0.7
－0.8
－0.8
－0.8
－0.8
0 10 20 30 [℃]－10
ALL
0 TA10
20meeting
30 [℃]－10
0 10 20 30
%/℃
－0.5
－10
#5
0 10 20 30 [℃]－10
#9
0 10 20 30
Temperature Coefficients of YAP
%/℃
%/℃
%/℃
%/℃
+0.2
+0.2
+0.2
+0.2
#2
#3
#4
0
0
0
0
－0.2
－0.2
－0.2
－0.2
－0.4
－0.4
－0.4
－0.4
－0.6
－0.6
－0.6
－0.6
－10
0 10 20 30 [℃]－10
0 10 20 30 [℃]－10
0 10 20 30 [℃]－10
%/℃
%/℃
%/℃
%/℃
+0.2
+0.2
+0.2
+0.2
#6
~ -0.2 %/deg
#7
#8
0
0
0
0
－0.2
－0.2
－0.2
－0.2
－0.4
－0.4
－0.4
－0.4
－0.6
－0.6
－0.6
－0.4
－10
0 10 20 30 [℃]－10
0 10 20 30 [℃]－10
0 10 20 30 [℃]－10
#5
0 10 20 30
#9
0 10 20 30
Other items
(filters,QE,CE,uniformity)
XY-Scanner
HITACHI U-1100
Spectrophotometer
Paraglas
transparency
paraglas
PMT
BG3
BG3
transparency
PMT uniformity
C.E. (HAMAMATSU)
0.909 +0.005 -0.020
Q.E.
(HAMMATSU)
PMT uniformity (XY Scanner)
XY
Scanner
•8LED
•Spot: 4mm
•Step: 4mm
•We create typical uniformity by using 253PMTs
(256 – 3 with YAP).
•Because of position and direction of each LED is
difference, we can obtain the fine uniformity map
better than the resolution of XY Scanner. We get
the uniformity map of 1mm×1mm resolution.
•Comparison with HAMAMATSU
measurement
→ Consistent!
Mirror reflectance
KONICA MINOLTA CM-2500d
Measurement point
e.g.) BRM,camera10,mirror3
(most dirty mirror)
Mirror washing→
•In most dirty term, reflectance
is affected by
Lower telescope：~-10%
Upper telescope：~-5%
•But each reflectance was
almost recovered by mirror
washing
Atmospheric
- LIDAR and cloud monitor LIDAR
LASER:
5mJ,355nm
30cm telescope
LIDAR is operated
every start & end
time of observation
IR Camera
The 14 pictures is taken every 1 hour.
12 picture is corresponded the F.O.V. of each 12 telescope.
Central Laser Facility
Central Laser Facility (CLF)
Steerable Nd:YAG laser 355 nm, 5 mJ
Black Rock Mesa
Shooting every 1 hour.
Atmospheric monitoring, “Test beam”
June 13, 2007, 05:45 (UTC)
Long Ridge
Peak time diff. < 100ns
frame head (sec)=
01.0000630
frame head =
01.0000630
TA-LINAC
▌ Linacの絵
TA-LINAC –motivationUncertainties of FD (design report of TA)
•Fluorescence yield
15%
•Transparency of Air
11%
•Telescope Calibration 10%
•Reconstruction
6%
Air shower
More than 20%
Absolute energy
calibration!
Linac
Beam
F
D
10km
100m
We can get integrated
calibration constant except
for air.
End-to-end calibration!
(We can connect energy
deposit to FADC count
directly.)
TA-LINAC -Basic specsSpecs of TA-LINAC
•Particle：e•Energy：10, 20, 30, 40 MeV
(variable)
•Pulse width：1μsec
•Peak current：0.16mA
(109e-(=160pC)/pulse)
•Frequency：~1Hz
•Distance from FD：100m
：F.O.V.(upper camera)
：F.O.V.(lower camera)
vertical
FD
@KEK
Construction : finished
Beam test
: finished
(08/Feb/22 – 08/Dec/10 716hours)
Linac
horizontal
100m
Simulated by geant4 (40MeV)
TA-LINAC –Result of beam testWaveforms
RF
Output beam
Beam Energy Spectrum
●
Data Set 1
●
Data Set 2
●
Data Set 3
Peak=39.7MeV
Spread < 1%
Beam Charge w/ Faraday Cup( pC/pulse/q)
EGUN
Beam Current Measurements
Mon1 : Faraday Cup (absolute)
Mon2 : Core Monitor (relative)
Reference
value = 160pC
+ Data set#1( ‘08 Nov.11th )
+ Data set#2( ‘08 Nov.12th )
+ Data set#3( ‘08 Nov.20th )
+ Data set#4( ‘08 Nov.21th )
+ Data set#5( ‘08 Nov.25th )
Core Monitor Output (mV×μs/pulse )
Diff. btw each Data : less than 5%
TA-LINAC –Current StatusFeb/06 @KEK
•Beam Test @KEK
•Beam test was finished at Dec/10.
•Transport to Utah from KEK
•Preparation for carrying : almost finished.
•Shipping from YOKOHAMA : Mar/1(?)
•TALinac will be arrived at Utah on end of Mar
•Shooting at Utah
•We can start shooting at next Apr-May !!.
Conclusion
▌ Linacの絵
FD Calibration
•The 1st data set of telescope calibration was almost
prepared.
•TA-LINAC calibration will be started at next Apr-May.
TA
•TA will present the first result at ICRC09 with data
equivalent of about 1 AGASA.
Grazie mille
note
TA-LINAC
–for fluorescence yield measurement▌ TA-FD can be calibrated end-to-end by TA-LINAC
▌ The difference btw LINAC beam and Air shower
►The height of the emission the photon
◘ Air shower (XMAX) ~ a few km
◘ LINAC beam ~70m
►Atmospheric condition
◘ Pressure, temperature has systematic difference.
◘ The variation of humidity is bigger than high atmosphere.
◘ (affected by the rain of before days.
►Our countermeasure
◘ Use result of yield measurement
◘ Use the result of only dry days.
►Of cause, we can measure this dependence by using
daily difference of atmospheric condition.
Mirror reflectance 1
KONICA MINOLTA CM-2500d1, The measured
(360～740nm,10nm pitch) data is consistent
with maker data
except for short
wavelength.
2, In this variation of
reflectance, We can see
•Height dependence
•No wavelength dependence
So we use
Maker data
•spectrum
•Absolute reflectance
at installation.
2008/06 (before washing)
LR upper telescope
Variation from installation
Measured data by CM2500d
•Relative variation of
reflectance
Mirror reflectance 2
•We prepared data mirror by mirror.
•250nm-740nm
•Mean ± standard deviation.
•1nm supplement with natural cubic spline.
•10 days supplement with linear approximation.
Measurement point
e.g.) BRM,camera10,mirror3
(most dirty mirror)
Mirror washing→
•In most dirty term, reflectance
is affected by
Lower telescope：~-10%
Upper telescope：~-5%
•But each reflectance was
almost recovered by mirror
washing
PMT uniformity (XY Scanner)
XY
Scanner
•Spot: 4mm
•Step: 4mm
•8LED
Method of analysis
•We adjust position of each PMTs by center of
gravity.
•After normalization, we add data of each PMTs.
(intensity of each LEDs)
•This data is normalized by “The average value of
each bins inside circle (dia. 36mm) will be 1”. This
condition is determined by CRAYS.
Comparison with HAMAMATSU measurement →
XY Scanner PMT境界
•PMTごとの中心距離は
62mm
•全体の積分値に対する
境界の外のBinの積分値
の割合は
境界線の外のBin→0.1%
境界線上のBin→0.9%
PMT境界
Uniformity:
ratio of deviation in each bins
•Evaluation of characteristics of each PMTs.
•sigma/mean ratio plot.
•Peak value is about 4%. High sensitivity area has this value.
•The edge area (low sensitivity) has bigger error ratio.
•Inside 90% circle area (dia. 27.5mm), maximum value is 33%, and 95% is less than
10%.
2007/11の鏡洗浄前後のデータ追加
反射率の時間変化による
系統誤差の見積もり
時間変化の絵の描き方
①, 全データ使用
②, 2007/11は一個前の測定データを使用
赤：①
青：②
全ての鏡ごとに①と②
を比較し、差が最大と
なる値を求める。
BRM
camera4
反射率の時間変化による
系統誤差の見積もり2
BRM,LRの全432枚の鏡についてのデー
タ。
全データ使用の場合を測定結果とし、
2007/11の補正を入れた場合に対してどの
程度反射率が減少するのかを見積もった。
ピークは～-2%、最大で-7%程度
通常のイベントに対する影響をさっく
り見積もる。
通常のイベントによる光スポットは、
18枚の鏡を大体均等に使っていると仮定。
→18枚の平均値が影響
下のカメラで最大-3.5%、上のカメラで
最大-2%程度。
正確な値はシミュレーションで。
反射率の分布
それぞれ6点しか測定していないので分布が分からない。
各列毎の鏡測定データを集めて、分布を見る。
2008/06,LR,上下のカメラ
下の図は360nmの物
まぁまぁガウス分布で合っている。→とりあえずガウス分布
それぞれの測定値は平均値、標準誤差、標準誤差/(測定点数)^0.5の3つとする。
TA-Linac -Basic specsSpecs of TA-Linac
•Particle：e•Energy：10, 20, 30, 40 MeV
(variable)
•Pulse width：1μsec
•Peak current：0.16mA
(109e-(=160pC)/pulse)
•Frequency：1Hz
•Distance from FD：100m
：F.O.V.(upper camera)
：F.O.V.(lower camera)
vertical
40MeV×109e- @100m → ~1016eV
⇔1020 eV @10km
We have to prepare power
generator and cooling water by
ourselves.
FD
Linac
horizontal
We install this systems in two
containers.(movable?)
100m
Simulated by geant4 (40MeV)
Mirror calibration
Curvature radius
Spot size at curvature radius
measured by TAMED
Light source
Image
scanner
Number of mirrors
Number of mirrors
mirror
TAMED
Spot size @ curvature radius [mm]
Reflectance (λ dependence)
measured by Spectrophotometer
(Konica-Minolta CM-2500d)
360nm～740nm
Reflectance [%]
Curvature radius [mm]
90
85
360
420
Wavelength [mm]
Mirror alignment
All mirrors were
adjusted using BANANA-3
BANANA-3
6067mm
LED
Spot
Laser
(center axis)
LED
Spot
~20mm
Current 1mip gain distribution
E. Kido
gain distribution(detector): 45±5 count
At under 4*10^6 gain 1mip peak are around 70,
(some PMT is more higher).
Maximum Number of particle
Hit in 20 nsec time bin
as function of distance from core
Typ：
at up to 570 m from core
TA can measure with
less non-linearity than 5%.
Typ
570m
Slide : by M. Chikawa (2007)
TA IR camera
IR data taking sequence
Once per 50min (3000 sec)
14 pictures in a sequence
•12 directions : 6 lower (12 deg) and 6 upper (30 deg)
•Vertical, horizontal
Sometimes there are missing pictures of
some directions
•(Instructions (PC ->
•By analyzing PC logs
camera) did not received correctly)
and time stamps of the IR data, missing parts
identified.
13
14
(vertical) (horizontal)
7
8
9
10
11
12
6
5
4
3
2
1
Statistics
2007/Dec/29 - 2009/Jan/04
Year
Month
Days
# Pictures
#/day
Total
2007
12
2
123
62
123
2008
1
17
1641
97
1764
2
13
1320
102
3084
3
12
1174
98
4258
4
12
1970
164
6228
5
12
2084
174
8312
6
9
537
60
8849
7
7
406
58
9255
8
20
1500
75
10755
9
15
1423
95
12178
10
16
1651
103
13829
11
15
1246
83
15075
12
12
1535
128
16610
1
2
238
119
16848
2009
Gallery
“Happy Night”
2008/Nov/06
08:02
08:59
10:03
Fitting result
0
50
100
150 [FADC count]
Fitting result (log arithmetic)
0
100
200
300 [FADC count]