![A Multiparty Computation Approach to Threshold ECDSA€¦ · Threshold ECDSA • Limited schemes based on Paillier encryption: [MacKenzie Reiter 04], [Gennaro Goldfeder Narayanan](https://static.fdocument.org/doc/165x107/5f47990511a80523873cee1a/a-multiparty-computation-approach-to-threshold-ecdsa-threshold-ecdsa-a-limited.jpg)
π 0 -threshold measurements ( unpol. photons )
19
π π 0 0 -threshold measurements -threshold measurements ( ( unpol. photons unpol. photons ) ) ► Date : Date : Sep-Oct 2007. Sep-Oct 2007. ► Ebeam: Ebeam: 450.0 MeV. 450.0 MeV. ► E E γ : : 130 – 420 MeV. 130 – 420 MeV. ► NMR : NMR : 0.539456(run1), 0.539456(run1), 0.538114 (run2). 0.538114 (run2).
description
π 0 -threshold measurements ( unpol. photons ). Date : Sep-Oct 2007. Ebeam: 450.0 MeV. E γ : 130 – 420 MeV. NMR : 0.539456(run1), 0.538114 (run2). σ tot ( γ +p p+ π 0 ) run 1 & SAID. σ tot σ tot * 1.05. σ tot ( γ +p p+ π 0 ) run 1 & SAID. two regions: - PowerPoint PPT Presentation
Transcript of π 0 -threshold measurements ( unpol. photons )
ππ00-threshold measurements-threshold measurements((unpol. photonsunpol. photons))
► Date : Date : Sep-Oct 2007.Sep-Oct 2007.
► Ebeam: Ebeam: 450.0 MeV.450.0 MeV.
► EEγγ : : 130 – 420 MeV.130 – 420 MeV.
► NMR : NMR : 0.539456(run1), 0.539456(run1), 0.538114 (run2).0.538114 (run2).
σσtottot ( (γγ+p+pp+p+ππ00))runrun11 & SAID & SAID
σtot σtot * 1.05
σσtottot ( (γγ+p+pp+p+ππ00))runrun11 & SAID & SAID
two regions:
high & low Eγ
σσtottot at low & highat low & high E Eγγ
low Eγ: shift ~ -2 MeV high Eγ: shift ~ +4 MeV
Moeller scatteringMoeller scattering
Background for Moeller:Background for Moeller:Triplet ElectroproductionTriplet Electroproduction
σ ~ Z2
two electrons – in Tagger,
a positron – out.
Detection of Moeller electrons in TaggerDetection of Moeller electrons in Tagger
►Coincidence of two electrons:Coincidence of two electrons:
| T| T11 – T – T22 | < 1 ns | < 1 ns
►Difference of electrons energies:Difference of electrons energies:
| E| E11 - E - E22 |> 10 MeV |> 10 MeV
Moeller in TaggerMoeller in Tagger
6 MeV shift of Moeller peak6 MeV shift of Moeller peak
Tagger channel vs Moeller peakTagger channel vs Moeller peak
3.5 MeV shift3.5 MeV shift in 2007in 2007
Oct2007, 883 MeV Jul2007, 1508 MeV
2.3 MeV shift in Jun20042.3 MeV shift in Jun2004
((ππ00-threshold, linpol)-threshold, linpol)
radiator = Diamond
Ebeam = 450 MeV
Old Tagger measurementsOld Tagger measurements
Radiator = Diamond
Ebeam = 882 MeV
Jul04, Sep04, Dec95
shifted CB-data, SAID & MAIDshifted CB-data, SAID & MAID
Control region: 165 – 175 MeV
Shift: ~ 2 MeV
shifted CB-data & TAPS shifted CB-data & TAPS Dec95Dec95
TAPS-95 : A.Schmidt, Mainz
Fine step photon energies:
no Microscope,just change Tagger field
CB-data, SAID & MAIDCB-data, SAID & MAIDnear thresholdnear threshold
γ+pp+ξ( ξ γ γ )
Ethr=147.5 +/- 0.5 MeV
mξ=137.5 +/- 0.5 MeV
Investigation of TaggerInvestigation of Taggerwith Moeller scatteringwith Moeller scattering
►Tagger channels: Tagger channels: 1 – 352.1 – 352.►EEbeambeam: : 180, 450, 8180, 450, 88383, 1508 , 1508
MeV.MeV.►Radiator: Radiator: Diamond.Diamond.►Beam current: Beam current: 1nA, 10nA, 50nA.1nA, 10nA, 50nA.
AttenuationAttenuation length of NaIlength of NaI
PM
AmBe
Eγ=4.44 MeV
ΝαΙ
Attenuation length of NaIAttenuation length of NaI
PM
AmBe
Eγ=4.44 MeVAmBe
ΝαΙ
