Calibration of centre-of-mass energies at LEP2 for a precise measurement of the W boson mass
Z'-boson mass prediction based on neural network s analysis of LEP2 data
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Transcript of Z'-boson mass prediction based on neural network s analysis of LEP2 data
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Z'-boson mass predictionbased on neural networks
analysis of LEP2 data
A.N.Buryk and V.V.Skalozub
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Many theories predict Z’-boson existance.
There are many methods to search for it.
But the lack of accessible nowadays experimental data doesn’t allow to find it.
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Searching for Z' is one of the goals
of experiments at LHC
Z’-boson mass prediction is needed
with the highest accessible precision
Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.SkalozubZ'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
TeVmZ 2.17.0' One-parameter fit model-independent search
LEP2 data set
Model-dependent searchsearch at CDF II TeVmZ 923.0'
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Starting point for this work was “Model-independent search for the Abelian Z’-boson in the Bhabha process”, made by A.V.Gulov and
V.V.Skalozub
Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.SkalozubZ'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
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Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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The Bhabha process was investigatedFor this process we have only one equation from the third formula:
The leading-order differential cross-section of the Bhabha process depends on next combinations of Z’-boson couplings:
Taking into account RG equations they are reduced to three parameters:
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.SkalozubZ'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Neural network analysis
Neural network was trained to discard the data,Neural network was trained to discard the data,which are associated with a backgroundwhich are associated with a background
SignalSignal: the differential cross-section for the Bhabha process : the differential cross-section for the Bhabha process obtained within the SM, extended by the Z‘-bosonobtained within the SM, extended by the Z‘-boson
BackgroundBackground: the deviation from the signal by the: the deviation from the signal by thevalue, equals to the redoubled uncertainty of LEP2 value, equals to the redoubled uncertainty of LEP2
experimental dataexperimental data
Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.SkalozubZ'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.SkalozubZ'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
We used neural networks with 2 incoming neurons, 10 hidden neurons an 1 outgoing neurons.
Training algorithm with back propagation of the error was used.After processing by the network we discard 20% of the uncertainty.
To construct and train neural networks the MLPFit package was used.
To process the data with obtained neural networks necessary programs were written.
L3 183-189 GeV OPAL 130-207 GeVALEPH 130-183 GeV DELPHI 189-207 GeV
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
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Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
BEFOREAFTER
95% CL area for v2
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Search for Z'-boson using neural networks within LEP2 data set A.N.Buryk and V.V.Skalozub
BEFOREAFTER
95% CL area for a2
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub
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TeVmZ 2.17.0'
TeVmZ 05.153.0' Neural networktwo-parameter fit
One-parameter fit
Z'-boson mass prediction based on neural networks analysis of LEP2 data A.N.Buryk and V.V.Skalozub