1. Estimation of Systematic Error for "R" which Appear in the Formula,
Exp._No.of.Ev._at_SK = R * Obs._No.of.Ev._at_near_det.
(Error Induced by the Uncertainty of Flux_Ratio Only)
K2K Collaboration is using CHO Model as an estimator of Flux_Ratio;
Neutrino_Flux_at_SK / Neutrino_Flux_at_Near,whose reliability is guaranteed by the Pion Monitor Measurement above 1GeV neutrino energy within Pion Monitor Measurement Error.Here, systematic error of R induced by the uncertainty of Flux_Ratio(it is the Pion Monitor Measurement Error) is calculated with taking into account energy dependent Flux_Ratio uncertainty as follows.
The Exp._No.of.Ev._at_SK is related to Neutrino Flux Ratio as follows.Exp._No.of.Ev._at_SKWhere
= R * Obs._No.of.Ev._at_near_det.
= t_ratio * SUM_OF_Neutrino_ENERGY_BIN[ n_near * f_ratio * c_ratio * e_ratio ]t_ratio: target mass ratio (far_det/near_det)As you see, this is an EXACT RELATION. Then R is explicitly written down as
n_near: No.of.Ev. at near det for this energy bin
f_ratio: neutrino flux_ratio (far_det/near_det) for this energy bin
c_ratio: neutrino cross section ratio (far_det/near_det) for this energy bin
e_ratio : detection efficiency ratio (far_det/near_det) for this energy binR = ( 1 / Obs._No.of.Ev._at_near_det. ) * t_ratio * SUM_OF_Neutrino_ENERGY_BIN[ n_near * f_ratio * c_ratio * e_ratio ]Estimation of systematic error for R is based on this formula.Used numerical informations are
I) Error of Flux_Ratio estimated by the Pion_Monitor_Measurement as a function of neutrino energy. It is summarized in TableThen systematic Error of R is calculated with adding the error for each energy region LINEARLY.Note:II) " Flux * Cross_Section " Table Prepared by Hayato
a)Since there is no pion monitor estimation below 1GeV, Jim Hill's MC based error estimation for Flux_Ratio;
0.0 GeV - 0.5 GeV +5.1% - 9.5%
0.5 GeV - 1.0 GeV +7.3% - 2.5%
is used for this region.b)In case of 0% detection efficiency (e.g. Scifi 0-0.5GeV), the Absolute_Neutrino_Flux information is necessary(not the Flux_Ratio).
For this part, number of expected at SK can't be done by usual " near * far/near " method.
Thus the uncertainty is estimated by each near detector group as a FLUX UNCERTAINTY separately for this part.
Probably each near detector group had better to utilize its own different analysis thresholds for SK event analysis to minimize the systematic error.
Though it is necessary to treat three different SK expected...III) Detection efficiency as a function of neutrino energy
Jun.'99
0-0.5 0.5-1.0 1.0-1.5 1.5-2.0 2.0-2.5 2.5< (GeV)
1kt 24.8 % 58.8 % 71.5 % 75.7 % 81.5 % 83.1 %
Scifi 0.0 % 3.4 % 16.0 % 24.0 % 31.0 % 36.0 %
Mu 0.0 % 15.7 % 36.3 % 45.7 % 51.9 % 47.3 %
SK 54.9 % 70.1 % 78.8 % 82.3 % 82.2 % 80.3 %Since Nov.'99
0-0.5 0.5-1.0 1.0-1.5 1.5-2.0 2.0-2.5 2.5< (GeV)
1kt 23.3 % 58.9 % 70.9 % 77.7 % 82.7 % 83.1 %
Scifi 0.0 % 3.2 % 18.0% 30.0 % 37.0 % 40.0 %
Mu 0.0 % 16.0 % 36.5 % 45.7 % 52.0% 47.5 %
SK 54.4 % 70.1 % 78.8 % 82.3 % 82.1 % 80.2 %
IIII) Corresponding Fiducial MassFinally here is a Result
(Uncertainty of R. Induced by the Uncertainty of Flux_Ratio Only.)1kt Jun.'99 +13.6% -9.9% Since Nov.'99 + 5.6% -7.3%
Scifi Jun.'99 +13.6% -9.8% Since Nov.'99 + 5.6% -7.1%
Mu Jun.'99 +13.6% -9.8% Since Nov.'99 + 5.6% -7.1%
2. To be done in FutureI) Comparison of neutrino spectrum predicted by the Pion Monitor with measurement by each subdetector1ktII) Extraction of more precise energy information (say 250Mev bin) from Pion Monitor Data
Scifi
Muon_Chamber
(For Comparison, above about 1GeV information is necessary)
A) Figure in the 1st Paperpaper.ps
B) Estimated Neutrino Spectrum by the Pion_Monitor at Near (r=3.0m fiducial) and Far Detector with Beam M.C. Predictionspect_jun.ps (Jun. Configuration)C) Estimated Far Near Neutrino Flux Ratio by the Pion_Monitor with Beam M.C. Prediction
spect_nov.ps (Nov. Configuration)Upper for Near Detector and Lower for Far Detector<Message of This Figure>
M.C. is normalized with Near Detector Data Entry above 1GeV
M.C. Error is for Statistical
The Shape of the Spectrum at Near and Far of Our MC is Guaranteed by the Pion Monitor Measurement above 1GeV (Absolute Flux is not Guaranteed by the Pion Monitor Measurement)ratio_jun.ps (Jun. Configuration)
ratio_nov.ps (Nov. Configuration)M.C. Error is for Statistical<Message of This Figure>
The Far/Near Ratio of Our MC is Guaranteed by the Pion Monitor Measurement above 1GeV
D) Centroid of Muons Measured at Muon Pit as a function of time from June '99 to June '00aiming.psE) Stability of Muon YieldFirst Page for Ionization Chamber X(Horizontal) Small Value Correspond to NORTH<Message of This Figure>
Second Page for Ionization Chamber Y(Vertical) Small Value Correspond to DOWN
Vertical Line indicate the end time of
June '99, Nov. '99, Jan.'00, Feb.'00, Mar.'00, May'00, June'00 data taking period.
Beam is Aimed to SK within about 1m rad Accuracy. This measurement is based on "SPILL by SPILL Information" and "High Energy Muon
Information"stability.psVertical Line indicate the end time of<Message of This Figure>
June '99, Nov. '99, Jan.'00, Feb.'00, Mar.'00, May'00, June'00 data taking period.
The muon yield normalized to proton intensity measured by a current transformer is stable spill-by-spill within
a measurement uncertainty of 2%. This measurement is based on "SPILL by SPILL Information" and "High Energy Muon
Information"
1) Cherenkov Light Distribution Measured by the Pion_Monitor at Various Refractive Indices(n)demo.ps (Jun. Configuration)2) Electromagnetic Activity (Background) which will be Subtracted are Indicated with Hatch
demo_nov.ps (Nov. Configuration)Pedestal Subtracted
PMT Relative Gain Correction Applied
Beam Intensity Correction Applied
PMT Saturation Correction Appliedbkg.ps (Jun. Configuration) 2 figures are enclosed3) Cherenkov Light Distribution Measured by the Pion_Monitor at Various Refractive Indices(n) with Fitting Result
bkg_nov.ps (Nov. Configuration) 2 figures are enclosedn=1.00026 and n=1.00034 for Jun. Data
n=1.00024 and n=1.00041 for Nov. Data
are used for normalization(with Using MC. GCALOR), respectively.
Pedestal Subtracted
PMT Relative Gain Correction Applied
Beam Intensity Correction Applied
PMT Saturation Correction Appliedpimonfit_jun.ps (Jun. Configuration)
pimonfit_nov.ps (Nov. Configuration)Pedestal Subtracted
PMT Relative Gain Correction Applied
Beam Intensity Correction Applied
PMT Saturation Correction Applied
ElectroMagnetic Background Subtracted
4) Estimated Pion Momentum/Angular Distribution by Fittingpikine_jun.ps (Jun. Configuration) 2 figures are enclosed
pikine_nov.ps (Nov. Configuration) 2 figures are enclosedSecond Page is Estimated Error for Fitting
5) Figure Shows you From which Decay Mode Neutrino Come. Based on CHO M.C.ElectroMagnetic Background Subtractedflux_mode.ps6) Expected Flux with Various Model. (Prepared by Wojciech Gajewski)offspct15.ps7) Summary of Systematic Error Estimation from Pion Monitor AnalysisExplanation by Wojciech Gajewski:
Wang(67) is the result of the compilation of the measurements made by Lundy (13.4 GeV), Dekker (11.8 & 18.8 & 23.1 GeV), Baker (10.9 & 20.9 & 30.9 GeV) and Fitch (33.9 GeV) using Dekker's measurements for the normalization and 227 mb measured by Bullettini for the absorption cross section (Denisov measured it to be 206 mb @ 20 GEV). The results of this compilation are described by Yamamoto and used by him for a comparison with his measurements. Yamamoto's measurements agreed surprisingly well with this compilation.
"Cho" is the result of the measurements performed by Derrick's group few years later to resolve a question of low cross sections measured by Telegdi's group (Lundy) on the same proton beam at Argonne and have a better understanding of their neutrino beam. I talk to Derrick few years ago and he claimed that his measurements were correct. They seem to work pretty well for us.
I started the programs with the target size 50cm^2 @ 300m and 200cm^2 @ 2.5km (this flux is been rescaled by 10^4 to SK, which introduces an overestimate error of ~5%). Target radius is 1.5cm and Horn Current is 250kAsyserr.ps 5 Pages8) Typical Muon Profile Measured by Muon Monitorsmufit.ps
9) Typical Proton Profile at V39 and Target(Nov Configuration)typ_proton_nov.ps10) <Caution>These 3 Figures are Made by Dr.Noumi from Beam Channel Group. You need acknowledgement from him when you use it for presentation<Caution>
elv.epsSchematic View of Neutrino Beam Line11) Schematic View of Pion and Muon Monitors
ts.eps Schematic View of Neutrino Beam Line
mussd.eps Schematic View of Muon Monitorpimon.ps Schematic View of Pion Monitor
mumon.ps Schematic View of Muon Monitor(Ionization Chamber)
silicon.ps Schematic View of Muon Monitor(Silicon Pad Detector)
12) Schematic View of Beam Monitor Locationmonitor_loc.ps
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