Pion Electroproduc/ons - int.washington.edu · Pion Electroproduc/ons Satoshi Nakamura Universidade...
Transcript of Pion Electroproduc/ons - int.washington.edu · Pion Electroproduc/ons Satoshi Nakamura Universidade...
PionElectroproduc/ons
SatoshiNakamura
UniversidadeCruzeirodoSul(Brazil)
--Analysisofelectrondataandextrac?onofelementaryamplitudes--
Introduc/on
Howelectronsca5eringisrelevanttoneutrinosca5ering
Rela/onbetweenneutrinoandelectron(photon)interac/ons
Lcc = GFVud2[Jλ
ccccλ
+ h.c. ]
Charged-current(CC)interac?on(e.g.νµ + n à µ- + p )
Jλcc =Vλ − Aλ cc
λ =ψµγλ (1−γ5 )ψν
Electromagne?cinterac?on(e.g.γ (*) + p à p )
Lem = e JλemAem
λ
Jλem =Vλ +V
ISλ
< p |Vλ | p > = − < n |Vλ | n > < p |V ISλ | p > = < n |V
ISλ | n >
V andVISinJem canbeseparatelydeterminedbyanalyzingphotonforQ2=0
andelectronreac?on(e,e’π), (e,e’X) dataforQ2≠0onbothprotonandneutrontargets, because:
Matrixelementfortheweakvectorcurrentisobtainedfromanalyzingelectromagne?cprocesses
< p |Vλ | n > = 2 < p |Vλ | p >
Strategytodevelopneutrino-nucleonmodel
• Vectorcurrent(formfactor)isfixedbyanalyzingelectronscaPeringdata
ßabundantprecisedataareavailable
• Axialcurrentamplitudecanbedeterminedbyanalyzing:
--Neutrino-nucleon,nucleusdata
--Parity-viola?nginclusiveelectronscaPeringdata
pionproduc?on
Strategytodevelopneutrino-nucleonmodel
• Vectorcurrent(formfactor)isfixedbyanalyzingelectronscaPeringdata
ßabundantprecisedataareavailable
• Axialcurrentamplitudecanbedeterminedbyanalyzing:
--Neutrino-nucleon,nucleusdata
--Parity-viola?nginclusiveelectronscaPeringdata
pionproduc?on
Strategytodevelopneutrino-nucleonmodel
• Vectorcurrent(formfactor)isfixedbyanalyzingelectronscaPeringdata
ßabundantprecisedataareavailable
• Axialcurrentamplitudecanbedeterminedbyanalyzing:
--Neutrino-nucleon,nucleusdata
(neutrino-deuteronpiondataßT.Sato’stalk)
--Parity-viola?nginclusiveelectronscaPeringdata
inthenucleonresonanceregion(laterinthistalk)
pionelectroproduc?ondata
pionproduc?ondata
NàN*
pionproduc?on
Strategytodevelopneutrino-nucleonmodel
• Vectorcurrent(formfactor)isfixedbyanalyzingelectronscaPeringdata
ßabundantprecisedataareavailable
• Axialcurrentamplitudecanbedeterminedbyanalyzing:
--Neutrino-nucleon,nucleusdata
(neutrino-deuteronpiondataßT.Sato’stalk)
--Parity-viola?nginclusiveelectronscaPeringdata
inthenucleonresonanceregion(laterinthistalk)
• Ouranalysisisdonewithdynamicalcoupled-channels(DCC)model
Inthefollowing:
*DCCmodel*DCCanalysisofpionelectroproduc?ondata*Comparisonwithothermodels*PVelectronscaPering
pionelectroproduc?ondata
pionproduc?ondata
NàN*
DynamicalCoupled-Channelsmodel
Unifieddescrip?onofpion-,electron-,andneutrino-inducedmesonproduc?ons
Dynamicalcoupled-channelsmodelformesonproduc?onsinresonanceregion
Δ
2nd 3rdDataforγ p è X
Severalnucleonresonancesformcharacteris?cpeaks 2π produc?oniscomparableto1πη, Κproduc?ons(mul?-channelcouplingsareimportantphysics)
Needdevelopamodel
todescribethesereac?ons
Dynamicalcoupled-channelsmodelforresonanceregion
Channel-couplingsrequiredbyunitarity(πΝ, ηΝ, ΚΛ, ΚΣ stablechannels)
2π produc?onmechanisms(ρΝ, σΝ , πΔ ßàππΝ channels)
Theore?callysoundmodelshouldalsoaccountfor:
DynamicalCoupled-Channels(DCC)modelaccountsforthesefeatures
developedthroughanalyzingdataforγΝ, πΝ è πΝ, ηΝ, ΚΛ, ΚΣ
∼ 26,000 datapoints
N*iΣ
i+ + + ...
Resonanceexcita?on+non-resonantmeson-exchangemechanisms
γ π, η, Κ
,
Coupled-channelsandhadronrescaPeringrequiredbyunitarityisfullytakenintoaccount
Kamanoetal.,PRC88,035209(2013)
Inaddi?on,γΝ channelisincludedperturba?vely
Coupled-channelLippmann-Schwingerequa?onformeson-baryonscaPering
,
Coupled-channelsandhadronrescaPeringrequiredbyunitarityisfullytakenintoaccount
Kamanoetal.,PRC88,035209(2013)
Inaddi?on,γΝ channelisincludedperturba?vely
Coupled-channelLippmann-Schwingerequa?onformeson-baryonscaPering
,
Coupled-channelsandhadronrescaPeringrequiredbyunitarityisfullytakenintoaccount
Kamanoetal.,PRC88,035209(2013)
Inaddi?on,γΝ channelisincludedperturba?vely
Coupled-channelLippmann-Schwingerequa?onformeson-baryonscaPering
,
Coupled-channelsandhadronrescaPeringrequiredbyunitarityisfullytakenintoaccount
Kamanoetal.,PRC88,035209(2013)
Inaddi?on,γΝ channelisincludedperturba?vely
Coupled-channelLippmann-Schwingerequa?onformeson-baryonscaPering
π
Δ
BysolvingtheLSequa?on,coupled-channelunitarityisfullytakenintoaccount
,
Kamanoetal.,PRC88,035209(2013)
Coupled-channelLippmann-Schwingerequa?onformeson-baryonscaPering
TV V V
Inaddi?on,γΝ channelisincludedperturba?vely
T
Kamano,Nakamura,Lee,Sato,2012 Kamano,Nakamura,Lee,Sato,PRC88(2013)
γpàπ0p dσ/dΩforW<2.1GeV ComparisonofDCCmodelwithdata
Reasonablefittodata
inthewholeresonanceregion
Vectorcurrent(Q2=0)for1π
Produc?oniswell-testedbydata
Par/alwaveamplitudesofπNsca5ering
Kamano, Nakamura, Lee, Sato, PRC88(2013)
Previous model (fitted to πN à πN data only) [PRC76 065201 (2007)]
Real part
Imaginary partData:SAIDπΝamplitude
Par/alwaveamplitudesofπNsca5ering
Kamano, Nakamura, Lee, Sato, PRC88(2013)
Previous model (fitted to πN à πN data only) [PRC76 065201 (2007)]
Real part
Imaginary partData:SAIDπΝamplitude
ConstraintonaxialcurrentthroughPCAC
Analysisofpionelectroproduc/ondata
withdynamicalcoupled-channelsmodel
SXN,H.Kamano,andT.Sato,Phys.Rev.D92,074024(2015)
γ * (q)e - (k)
e - (k’)
π
Crosssec?onforsinglepionelectroproduc?on
x*:variablesinCMofthefinalπΝ system
σX ( X = T, L, LT, LT ’, TT ) :structurefunc?onsh :electronhelicity
Only σT + ε σL contributestotheintegratedcrosssec?on
àMostimportantstructurefunc?ons
• p(e,e’π0)p• p(e,e’π+)n• both
Analysisofelectron-protonscaPeringdata
Purpose:DetermineQ2–dependenceofvectorcouplingofp-N*:VpN*(Q2)
Data:*1π electroproduc?on
0
1
2
3
1.2 1.4 1.6 1.8 2
Q2 (G
eV/c
)2
W (GeV)
Database
• p(e,e’π0)p• p(e,e’π+)n• both
Analysisofelectron-protonscaPeringdata
Purpose:DetermineQ2–dependenceofvectorcouplingofp-N*:VpN*(Q2)
Data:*1π electroproduc?on
0
1
2
3
1.2 1.4 1.6 1.8 2
Q2 (G
eV/c
)2
W (GeV)
Database
• p(e,e’π0)p• p(e,e’π+)n• both
Analysisofelectron-protonscaPeringdata
Purpose:DetermineQ2–dependenceofvectorcouplingofp-N*:VpN*(Q2)
Data:*1π electroproduc?on
0
1
2
3
1.2 1.4 1.6 1.8 2
Q2 (G
eV/c
)2
W (GeV)
Database
*Empiricalinclusiveinelas?cstructurefunc?onsσΤ , σL çChristyetal,PRC81(2010)
regionwhereinclusiveσΤ & σL arefiPed
AnalysisresultQ2=0.40(GeV/c)2
σΤ + ε σL forW=1.1–1.68GeV
p(e,e’π0)p p(e,e’π+)n
0
10
20
301100 1120 1140 1160 1180
1200
0
10
20
1220 1240
1260 1280 1300 1320
0
4
1340 1360 1380 1400
1420 1440
0
4 1460
1480 1500 1520
1540 1560
0
4
-1 0 1cos θπ*
1580
0 1cos θπ*
1600
0 1cos θπ*
1620
0 1cos θπ*
1640
0 1cos θπ*
1660
0 1cos θπ*
1680
0
10
201110 1130 1150 1170 1190
1210
0
10
1230 1250 1270 1290 1310 1330
0
5
101350 1370 1390 1410 1430
0 1cos θπ*
1450
0
5
10
-1 0 1cos θπ*
1470
0 1cos θπ*
1490
0 1cos θπ*
1510
0 1cos θπ*
1530
0 1cos θπ*
1550
0
200
400
1200 1400 1600 1800 2000
σT,
L (µ
b)
W (MeV)
AnalysisresultQ2=0.40(GeV/c)2
σΤ & σL (inclusiveinelas?c)
DCC
ChristyetalPRC81σΤ
σL
regionwhereinclusiveσΤ & σL arefiPed
0
1
2
31150 1170 1190
1210 1230 1250
0
1
21270 1290 1310 1330 1350 1370
0
1
21390 1410 1430 1450
1470 1490
0
1
2
1510 1530
1550 1570 1590 1610
0
1
21620 1630 1650 1660 1670 1700
0
1
2
-1 0 1cos θπ*
1740
0 1cos θπ*
1780
0 1cos θπ*
1830
0 1cos θπ*
1890
0 1cos θπ*
1950
0 1cos θπ*
2010
AnalysisresultQ2=1.76(GeV/c)2
σΤ + ε σL forW=1.1–2.1GeV
p(e,e’π0)p
p(e,e’π+)n
0
1
2
31100 1120 1140 1160 1180
1200
0
1
2
1220 1240
1260 1280 1300 1320
0
1
21340
0 1cos θπ*
1360
0 1cos θπ*
1380
0 1cos θπ*
1400
0 1cos θπ*
1420
0 1cos θπ*
1440
0
1
2
-1 0 1cos θπ*
1460
0
10
20
30
40
50
1200 1400 1600 1800 2000
σT,
L (µ
b)
W (MeV)
AnalysisresultQ2=1.76(GeV/c)2
σΤ & σL (inclusiveinelas?c)
DCC
ChristyetalPRC81σΤ
σL
regionwhereinclusiveσΤ & σL arefiPed
AnalysisresultQ2=2.95(GeV/c)2
σΤ + ε σL forW=1.11–1.67GeV
p(e,e’π0)p p(e,e’π+)n
0
0.5
11100 1130 1150 1170 1190
1210
0
0.5
1230
1250 1270
0 1cos θπ*
1290
0 1cos θπ*
1310
0 1cos θπ*
1330
0
0.5
-1 0 1cos θπ*
1350
0 1cos θπ*
1370
0 1cos θπ*
1390
0
0.5
11150 1170 1190
1210 1230 1250
0
0.5
1270 1290 1310 1330 1350 1370
0
0.5
1 1390 1410 1430
1450 1470 1490
0
0.5
1
1510 1530 1550
0 1cos θπ*
1570
0 1cos θπ*
1590
0 1cos θπ*
1610
0
0.5
-1 0 1cos θπ*
1630
0 1cos θπ*
1650
0 1cos θπ*
1670
10
20
1200 1400 1600 1800 2000
σT,
L (µ
b)
W (MeV)
AnalysisresultQ2=2.95(GeV/c)2
σΤ & σL (inclusiveinelas?c)
DCC
ChristyetalPRC81σΤ
σL
regionwhereinclusiveσΤ & σL arefiPed
1π
1π
Data:JLabE00-002(preliminary)
• Reasonablefittodataforapplica?ontoneutrinointerac?ons• Important2π contribu?onsforhighWregion
Inclusiveelectron-protonsca5ering
0
0.1
0.2
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
)
W (GeV)
Ee=5.498 GeVQ2=0.96-1.3 (GeV/c)2
θe’=12.97o
0
1
2
3
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
)
W (GeV)
Ee=3.118 GeVθe’=12.45o
Q2=0.21-0.40 (GeV/c)2
Purpose:Vectorcouplingofneutron-N*anditsQ2–dependence:VnN*(Q2) (I=1/2)
I=3/2 parthasbeenfixedbyprotontargetdata
Analysisofelectron-’neutron’scaPeringdata
Data:*1π photoproduc?on(Q2=0)
*Empiricalinclusiveinelas?cstructurefunc?onsσΤ , σL (Q2≠0) çChristyandBosted,PRC77(2010),81(2010)fiPedtoelectron-deuterondataandelectron-protonstructurefunc?onsaresubtracted
AnalysisresultQ2=0 dσ / dΩ (γ n è π-p) forW=1.1–2.0GeV
0
20
401130 1143 1148 1155
1163 1171 1179 1187 1195 1200 1206 1212
0
201218 1224 1230
1237 1245 1252 1257 1263 1271 1276 1282 1288
0
101300 1308 1315 1320 1329 1336 1343 1349 1357 1363 1371 1378
0
101391 1398 1405 1411 1418 1425 1431 1438 1444 1449 1457 1463
0
101469 1476 1483 1490 1495 1508 1514 1520 1526 1533 1539 1545
0
51551 1557 1569 1575 1587 1604 1616 1625 1633 1648 1662 1673
0
51690 1704 1718 1728 1734 1739 1745 1758 1771 1785 1798
0 1cos θπ*
1819
0
2
4
-1 0 1cos θπ*
1824
0 1cos θπ*
1844
0 1cos θπ*
1849
0 1cos θπ*
1869
0 1cos θπ*
1875
0 1cos θπ*
1894
0 1cos θπ*
1899
0 1cos θπ*
1924
0 1cos θπ*
1948
0 1cos θπ*
1972
0 1cos θπ*
1996
AnalysisresultQ2=0
dσ / dΩ (γ n è π0n) forW=1.2–1.9GeV
0
20
40
1206 1230 1252 1257
1276 1282 1308 1320 1336 1349 1357 1363
0
51391
1405 1425 1457 1469 1483 1490 1495
0 1cos θπ*
1514
0 1cos θπ*
1520
0 1cos θπ*
1526
0 1cos θπ*
1539
0
2
4
-1 0 1cos θπ*
1551
0 1cos θπ*
1581
0 1cos θπ*
1604
0 1cos θπ*
1611
0 1cos θπ*
1616
0 1cos θπ*
1764
0 1cos θπ*
1869
0 1cos θπ*
1875
10
20
30
1200 1400 1600 1800 2000
σT,
L (µ
b)
W (MeV)
50
100
150
1200 1400 1600 1800 2000
σT,
L (µ
b)
W (MeV)
Analysisresult
Q2=1(GeV/c)2
σΤ & σL (inclusiveinelas?ce—-’n’ ) DCC
ChristyandBostedPRC77;81
σΤ
σL
Q2=2(GeV/c)2
σL
σΤ
Q2≠0
0
0.01
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
/A)
W (GeV)
Q2=1.76-2.64 (GeV/c)2θe’=25.00o
1π1π
Data:NPB(Proc.Suppl.)159,163(2006)
• Modelàaverageofelectron-protonandelectron-neutrondifferen?alcrosssec?ons
ànucleareffects(Fermimo?on,FSI)areignored
• SpreadofresonancewidthindataàFermimo?on
Inclusiveelectron-deuteronsca5ering
0
0.5
1
1.5
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
/A)
W (GeV)
Q2=0.44-0.66 (GeV/c)2θe’=10.65o
0
0.01
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
/A)
W (GeV)
Q2=1.76-2.64 (GeV/c)2θe’=25.00o
1π1π
Data:NPB(Proc.Suppl.)159,163(2006)
• Modelàaverageofelectron-protonandelectron-neutrondifferen?alcrosssec?ons
ànucleareffects(Fermimo?on,FSI)areignored
• SpreadofresonancewidthindataàFermimo?on
Inclusiveelectron-deuteronsca5ering
DCCvectorcurrentshasbeentestedbyofe—-p &e—-’n’dataforwholekinema>calregion
relevanttoneutrinointerac>onsofEν ≤ 2GeVàisospinsepara>onàweakvectorcurrent
0
0.5
1
1.5
1.2 1.4 1.6 1.8 2
d σ
/d Ω
d E
’ (µ
b/sr
GeV
/A)
W (GeV)
Q2=0.44-0.66 (GeV/c)2θe’=10.65o
EMNàN*transi?onformfactors
NàΔ(1232) H.Kamano,NSTAR2017
• Evaluatedattheresonancepoleposi?onàformfactorsarecomplex
EMNàN*transi?onformfactors
NàΝ (1440) H.Kamano,NSTAR2017
• Evaluatedattheresonancepoleposi?onàformfactorsarecomplex
Comparisonwithothermodels
Hernandez,SXN,Nieves,Sato,Sobczyk,inprepara?on
TheSLmodel T.SatoandT.S.H.Lee,PRC54,2660(1996)T.SatoandT.S.H.Lee,PRC63,055201(2001)
• Δ(1232)-excita?onmechanisms
• Meson-exchangenon-resonantmechanisms
• π N channelisincluded
• HadronrescaPeringandπ N unitarity
TheSLmodeldescribesπ Nà π N scaPeringandelectroweakpionproduc?onintheΔ(1232)-regionisreasonablydescribedinaunifiedmanner
Themodeltakesaccountof:
TheDCCmodelcanbeviewedasanextensionoftheSLmodel
byincludingothermeson-baryonandππ N channelsandresonances
TheHNVmodelHernandez,Nieves,Valverde,PRD76,033005(2007)Alvarez-Rusoetal.,PRD93,014016(2016)HernandezandNievesPRD95,053007(2017)
W W
W W
W
W
+ +
+ +
+
+
+
W
∆
∆N
N
N’N’
N’
N’
N’
π π
π π
π π
ππ
N’
N
NN N’
N
N π
N N
, D13
, D13
• Resonance-excita?onmechanisms
Δ(1232) andD13(1520)
• Non-resonantmechanisms
derivedfromchiralLagrangian
• HadronrescaPeringisnotexplicitly
considered
àphasesaremul?pliedtoP33
amplitudetosa?sfy
theWatsontheorem(unitarity)
• u-channelΔ propagatorismodified
tofitbePerνµ n à µ- π+ n data
ComparisonofDCC,SL,andHNVmodelsHernandez,SXN,Nieves,Sato,Sobczyk,inprepara?on
Inclusiveelectron-protonscaPeringData:PRL53,1627(1984)
• GoodagreementbetweenmodelsanddataattheΔ(1232) peak
• SL(HNV)modelgivessmallercrosssec?onshigher(lower)energies
Q2=0.04-0.18GeV2
Comparison(cont’d)Singlepionelectroproduc?on
• Goodagreementbetweenmodelsanddata
formostofstructurefunc?ons
• HNVmodelgivesrathersmallσLT’
forp ( e,e’ π0 ) p ß σLT’isfromnon-zerorela?vephasebetween
differentmechanismsandformfactors
ßDCCandSLmodelsincludemeson-loops
toproduceaddi?onalphases;HNVdoesnot
×
Q2=0.4GeV2,WπN = 1.22GeVp ( e,e’ π0 ) p p ( e,e’ π+ ) n
Parity-viola/ngelectron-nucleonsca5ering
andaxialformfactors
Inclusiveelectron-protonscaPering(e- p àe- X )
Differen?alcrosssec?onwithrespecttoleptonkinema?cs
em em
Wiem (W, Q2):structurefunc?ons(allinforma?onofhadrondynamicsencodedin)
W1em =
12
f J emx i2+ f J emy i
2( )f∑
i∑ δ (4)(pi + q− pf )
W2em =
Q2
!q 2W1em +
Q2
!q 2Q2
!qc2 f J em0 i
2
f∑
i∑ δ (4)(pi + q− pf )
γ∗ (q)
p
e -
X
e -
-
-
Parity-viola?nginclusiveelectron-protonscaPering
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
Parity-viola?nginclusiveelectron-protonscaPering
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
Jncµ = (1− 2sin2θW )Jem
µ − Visoscalarµ − A3
µ
Parity-viola?nginclusiveelectron-protonscaPering
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
Jncµ = (1− 2sin2θW )Jem
µ − Visoscalarµ − A3
µ
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
A = −Q2 GF
24πα2− 4sin2θW +ΔV +ΔA( )
Parity-viola?nginclusiveelectron-protonscaPering
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
A = −Q2 GF
24πα2− 4sin2θW +ΔV +ΔA( )
≈8.99x10-5(GeV-2) ≈1.075(mainterm)
1− 4sin2θW ≈ 0.08
Parity-viola?nginclusiveelectron-protonscaPering
Parity-viola?ngasymmetry
γ∗ (q)
p
e -
X
e -
Ζ (q)
p
e -
X
e -
+
A = −Q2 GF
24πα2− 4sin2θW +ΔV +ΔA( )
≈8.99x10-5(GeV-2) ≈1.075(mainterm)
2W3em-nc =W3
CC
∝ f Viso-vector i f Aiso-vector i*
à PVasymmetrydataforbackwardelectronkinema?cscanmeasure W3 forneutrinoCCprocess andaxialmatrixelement(formfactors)
•
1− 4sin2θW ≈ 0.08• ΔV ispropor?onaltoisoscalarcurrentàsmallinΔ(1232) region
Parity-viola?nginclusiveelectron-protonscaPering
A /Q2 = −89.9×10−6 1.075 + ΔV + ΔA( )
ΔV,ΔA contribu?onsfromSLmodel
ΔA gives∼10%correc?ontoA
θe’ = 110°θe’ = 60°
Matsui,Sato,Lee,PRC72,025204(2005)
[1/GeV2]
-120
-110
-100
-90
-80
0 0.2 0.4 0.6 0.8 1
A/Q
2 (x
10-6
/GeV
2 )
Q2 (GeV2)
MAN∆ = 1.0 GeV
MAN∆ = 1.2 GeV
Sensi?vityofPVasymmetrytoNàΔ(1232)axialformfactor
W = 1232 MeV, θe’ = 110°
• 5%precisionPVasymmetrydatamaydiscriminate0.2GeVdifferenceintheaxialmass
• Sensi?vitytoNàN*, Δ* (higherresonances)transi?onaxialformfactors
canbestudiedwiththeDCCmodel
NàΔ(1232)dipoleformfactorwithMA
NΔ
A /Q2 = −89.9 1.075 + ΔV + ΔA( )[10-6/GeV2]
ComparisonwithPVasymmetrydatafromJLab ThePVDISCollabora?on,PRC91045506(2015)
• Forwardelectronkinema?csàaxialcurrenthardlycontribute
• Devia?onfromdatainΔ(1232)maybefromnucleareffects(FSI,Fermimo?on,etc.)
• Devia?onsinhigherWregionàcallingimprovementonthemodel(isospinsepara?on)
Ee = 4.867 GeV, θe’ = 12.9°Q2
≈ 1 GeV2 nearΔ(1232)
W(GeV)
Deuterontargetdataàprotonandneutroncrosssec?onsaresimplysummedincalcula?on
A /Q2 = − 89.9 × 1.075+ΔV +ΔA( )[10-6/GeV2]
30-50%precisiondataforA alreadyexistàEventratemeasuredat0.3%precision
Conclusion
Extrac/ngelementaryvectoramplitudes(transi/onformfactors)
withDCCmodelfromelectronsca5eringdatainresonanceregion
StartwithDCCmodeldevelopedthroughanalyzing γΝ, πΝ è πΝ, ππΝ, ηΝ, ΚΛ, ΚΣ
è extensionofvectorcurrenttoQ2≠0region
throughanalysisofe—- p &e—-’n’ dataforW ≤ 2GeV,Q2≤ 3(GeV/c)2
à isospinseparatonàneutrino-inducedreac?ons
NàN*transi?onformfactorsaredetermined
Detailedcomparisonofstate-of-artelementarypionproduc/onmodels
Structurefunc?onsforpionelectroproduc?onfromDCC,SLandHNVmodelsarecompared
• Goodagreementbetweenmodelsanddataformostofstructurefunc?ons
• HNVmodelgivesσLT’forp ( e,e’ π0 ) p significantlysmallerthandata
DCCandSLmodelsreproducethedatabecausemeson-loopscangeneratephase
Parity-viola/ngelectron-nucleonsca5eringforextrac/ng
elementaryaxialamplitudes(transi/onformfactors)
• PVasymmetrydataforbackwardelectronkinema?cscanmeasure W3
forneutrinoCCprocess andaxialelementaryamplitude(formfactors)
• 5%precisionPVasymmetrydatamaydiscriminate0.2GeVdifferenceintheaxialmass
• Currentdataprecisionis30-50%forPVasymmetry(0.3%precisioneventrate)
• Needes?materadia?vecorrec?ons
ThankyouverymuchforyouraPen?on
Acknowledgments
• FinancialsupportforthisworkFAPESP2016/15618-8KAKENHIJP25105010
• Compu?ngresourceNERSCBEBOP,LCRC,ArgonneNa?onalLab
BACKUP
Kamano,Nakamura,Lee,Sato,2012
SXN,Kamano,Lee,Sato,arXiv:1804.04757γnàπ0n dσ/dΩforW<2GeV
0
18
dσ/dΩ
(µb/
sr)
0
6
dσ/dΩ
(µb/
sr)
-0.5 0 0.5cosθ
0
2
dσ/dΩ
(µb/
sr)
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
1202 1230 1254 1282 1310 1335 1346 1360
1371 1388 1413 1420 1454 1480 1489 1514
1540 1563 1600 1660 1720 1780 1840 1900
γnàπ-p
0
15
dσ/dΩ
(µb/
sr)
0
5
dσ/dΩ
(µb/
sr)
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
0
2
dσ/dΩ
(µb/
sr)
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
-0.5 0 0.5cosθ
1114 1233 1318 1353 1401 1435 1473 1498
1523 1561 1607 1653 1693 1731 1769 1800
1836 1872 1902 1948
:newfit
:previousfitPRC88(2013)
RecentMAMIdataincludedPRL112,142001(2014)
RecentJLabdataincludedPRC96,035204(2017)