Good morning. I'm Soshiki Shizuma from Japan's Mechanized Agency.Let me first introduce myself.I majored in Experimental Nuclear Physics at Kyushu University in Japan.I got a PhD about 20 years ago.I became a member of JAELE, which is the former institute of JAEA.So now I'm working on the nuclear structure physics by using photonuclear reaction.And I'm also working on the development of the non-destructive isotope identification of material by using gamma rays.So today I will talk about some of these my work.So I'll give you two lectures concerning photonuclear reaction data measurement and interpretation.So most of the lecture in this school is related to neutron industry reaction.So my lecture is on photo industry reaction.But I hope that my lecture will give you some information.So this is content of my lecture.So my lecture is divided into three parts.So past, present, and future photonuclear reaction measurement.So past means that before 90s.So I begin the lecture with introduction on photonuclear reaction and photonuclear reaction data.Then I will introduce you some of the photon source which is used in the past photonuclear reaction measurement.So the main interest of past photonuclear reaction measurement is to understanding the giant dipole resonance.So I will explain some of the property of the giant type of resonance.So then I will show you a compilation and evaluation of photonuclear reaction data.So next I will introduce you a new photon source which is laser-compton scattering yammer ray,which is using the recent photonuclear reaction measurement.Then I will show you a photonuclear reaction measurement and the nuclear resonance fluorescence measurement for nuclear cell physics and nuclear physics studies.So I will also show you an application of nuclear resonance fluorescence,which is a non-destructive isotope identification of nuclear materials.So then I will show you an analysis data in actual isotope which is necessary for this NDA technique.So finally I will show you a photonuclear reaction data with future light source.So this shows how the photonuclear reaction takes place.So when a nucleus absorbs a photon,so it immediately emits photons, neutrons and protons or heavier particles.So each particle emission has different threshold energy.So below the particle separation energy,elastic and inelastic photons scattering take place.So inelastic photons scattering is called nuclear resonance fluorescence.Since the level density is low at this energy region,sharp resonance corresponding to each nuclear level is observed.So with increasing the energy of photons,the nucleus starts to emit particles.So the cross-section of the particle emissiongradually increases showing a broad peakaround 15 to 20mm.So this is called giant type of resonance,which I will explain later in my lecture.The photonuclear reaction data consists of cross-section,photoneutron yield,angular distributionfor photo disk induced reactions such asγγNγPγαγφSo in addition to the cross-section of each reaction channels,these three cross-sections are important for several applications.The first one is total photo absorption cross-section,which is the sum of the cross-section of the neutron emission channels,such asγNγNPγ2Nγ3Nγφ.And the second one is photo absorption cross-section,which is equal to the sum of the total photoneutron cross-sectionof the charged particle emission,such asγPγDγα.So since the full-on force is strong for heavy nuclei,the cross-section for charged particle emission is small.So therefore the photo absorption cross-sectionis close to the total photoneutron cross-section.So on the other hand,for lighter nuclei,because of weaker full-on force,the particle emission competes with the neutron emission.So the cross-section for the charged particle emission is large.So the photo absorption cross-section is larger than the total photoneutron cross-section.So the last one is the photoneutron production cross-section,which is the sum of the number of neutrons produced in the reaction.So in this case,for the two-neutron production cross-section,the cross-section should be duplicated.And for the fission process,the cross-section of the photo fissionis multiplied by average multiplicity of the photo fission neutron.These photonuclear reaction data are important for several applications shown in this slide.So since the neutron can easily penetrate the matter,the photoneutron cross-section data is important for designing radiation shieldingand analysis of radiation transport.So photonuclear photoneutron data is also important forcalculations of absorbed doors in human body during therapy,since the neutron gives the damage to the human body.So the photonuclear reaction data are also important for fission and fusion reactor physicsand activation analysis,safe garden inspection technology,as well as the nuclear waste transmission.So since the elements are produced in stars by nuclear reaction,including photonuclear reaction,photonuclear reaction data is also important for nuclear physics,which I explained later in my lecture.In the first photonuclear reaction measurement,several kinds of photon source were used.So these are listed here.So I will explain the characteristics of each photon source.So this is an example of discrete gamma ray fromthermal neutron capture reaction developed at Central Banyan State University.So the neutron source is a 200 kilowatt full-type reactor.The source target such as aluminum, copper, chlorine irradiate with thermal neutrons.And each source target has a weight of a few kilograms.So the source target is placed next to the bismuth block,which is very thick to reduce the gamma ray from the reactor.So the thermal capture gamma rays pass through the air tube,water and paraffin and copper collimator.Water and paraffin is used to remove the neutron from the reactor.So the capture gamma ray is transported to the target position,which is placed at the center of the neutron detector.So this shows the source target and energy and the intensity of capture gamma rays.So the capture gamma ray is discrete with energy ranging from 5.4 to 10.8 mm.The intensity is between 10 to the 3 and 10 to the 5,most per square centimeter per second.So the relative intensity of the capture gamma ray depends on thethermal neutron capture cross-section for each source target.So this is the major cross-section for some of the ice torque.This figure shows the cross-section for Tantem 181 and Lichun 6.The data taken with the thermal capture gamma ray is shown with the field circle.And other data taken from the other photon source is also shown with the circle,open circle and open squares.So the uncertainty of the data taken by the thermal neutron capture gamma ray is large.This is due to the large uncertainty of the intensity of the thermal capture gamma ray.Brems line radiation is produced by the deceleration of a charged particle by nucleus.Usually electron accelerator is used to produce Brems line photons.Electron loses kinetic energy according to the energy conservation law.This figure shows the Brems line spectrum with the electron beam with the energy of 13.2 MeB.So maximum energy of photon is identical to the energy of electron about 13 MeB.Intensity is rapidly increasing with decreasing the energy of photon.This is the characteristic of the Brems line photon beam from intensity with continuous energy spectrum.This shows the Brems line facility at the elevator in Germany.Electrons are accelerated by superconducting renotes and transported to the radiator target by using these dipole magnets.Brems line photons are produced in the radiator target.Since the radiator target becomes very hot about 1,200 degrees.Usually Niobium is used as a radiator target because of high melting point about more than 2,000 degrees.Brems line photon is produced in this radiator target and transported to the target position to the experimental room through a long perimeter here.Brems line facility is very important to minimize the production of neutrons and photons in the experimental room.Brems line radiation has a continuous energy spectrum.Hot nuclear reaction yield is the folding of the cross-section and Brems line photon spectrum, sigma and k over the photon energy.So here the SN is the neutron separation energy and E0 is the electron beam energy and E gamma is the energy of photons.So the cross-section sigma can be obtained by unfolding this yield of curves measured in small increment of the electron energy.So this process requires accurate knowledge of the Brems line spectra for all electron energy and also requires stability in accelerator parameters such as the beam size and the beam intensity on the radiator target.And also requires large counting statistics because this process includes the subtraction of the cross-section yield measured at different energy, electron energy.So the majority of the photonuclear reaction data measured with Brems line radiation is obtained at the Moscow State University and University of Melbourne.The positive annihilation in flight is the quantum energy photon beam with various energy.Unlike the Brems line photons, the photonuclear cross-section can be obtained directly.So this kind of photon source was developed at Los Alamos National Laboratory and SACRE in France.So this shows the layout of the photon facility in Rivermore laboratory.So the positrons are first produced in the converter target by a pair creation from the Brems line photons generated by high energy electrons from electron accelerators.So the thin and high G material is used as a positron converter target.And the positrons are accelerated by linear accelerator and deflected by the bending magnet for energy selection.So the energy selected positron is used to hit an annihilation target.In this method,Brems line radiation is also produced in a radiation targetby a deceleration positron beam.In order to maximize the ratio between the annihilation photon and the Brems line photons.So thin and low Z target, like very room is used as an annihilation target.And the gamma beam is finally transported to the measurement point where the target is placed at the center of the neutron target.So this shows the layout of the SACRE facility.So the quantum energy photon beam is produced in the similar way to the Rivermore laboratory.So this is the typical photon spectrum from positive annihilation in flight, bottom one.So this spectrum has two components.So one is a mononet component from annihilation in flight.And other is a continuous component from positron Brems line.So measured cross section includes the contribution from both the component.The contribution from the positron Brems line photon have to be removed.So this can be done by subtraction of cross section measured with the electron Brems line photons from the measured cross section.In the top here,the quantum energy component of the annihilation flight is shown in the top here.So this was obtained by subtraction of the electron Brems line photons from the measured spectrum.So the energy width of this photon beam is typically about 10%.So many photon neutron reaction data using this kind of photon beam have been obtained at these two laboratory during the 60s and 80s.This shows the Brems line target photon facility at University Illinois.The Brems line photons are first produced in thin radiator target.So electron passing through this radiator target is deflected by spectrometer magnet.And the measured with the detector which is placed at the focal plane of the spectrometer.So the electron signal with the energy of ESC corresponds to the presence of a photon with energy of E gamma which is E0 minus ESC.So E0 is the energy of electron.Time for instance between the scattered electrons and the signal from the nuclear reaction product detectoridentifies that the reaction was produced by a photon of energy of E gamma.So the reaction was target photon having energy of E gamma.So energy resolution of this photon source depends on the optics of the spectrometer magnetand also the spatial distribution of the electron detector.This is a cross-section photon electron cross-section data for this mass 208 taken with the target photon, Brems line target photon.And the light figure is a neutron time of light spectrum for the same nucleus.So by using this method both the instant photon energy and the energy of emitted neutron can be measured simultaneously.I explain the four types of the photon source which is used in the parts photon nuclear reaction measurement.So the first photon measurement the main purpose is understanding the giant type of resonance.So this figure shows the photo absorption cross-section for oxygen 18 and red 208.So we can see a broad piece in this spectrum.So the giant type of resonance observed at 20 to 25 MeB for light nuclei.And around 15 MeB for heavy nuclei.So it is thought that the giant type of resonance is produced by a collective vibration in which the part of proton and neutron moving against each other.So this produces the electric dipole field of photons.As we can see in the top spectrum, top figure, giant type of resonance is strongly fragmented over a wide energy range for the light nuclei.So this is because that for light nuclei, level density is low.The contribution from each nuclear level is rather large.So with heavy nuclei, the giant type of resonance consists of one or two broad peaks which reflect the gross future of nucleus.For example, cross-section, the DDR consists of one broad peak for red 208.So red 208 is a spherical nucleus.Sperical nucleus has one broad peak.The giant type of resonance is split into two components as shown in this figure.So this figure is for the Gardner 160 which is a well-deformed nucleus like this shape.So this has two broad peaks around the energy of 11 and 16 MeB.So the lower resonance corresponds to the oscillation of neutrons and protons along the long axis.And higher resonance is oscillation along the short axis.The GDR is characterized as the Lorentzian parameters.So this shows the giant type of resonance for red 208.So the cross-section can be expressed as the Lorentzian function like this form.So here the EM is the peak energy of the GDR.And the sigma M is the peak cross-section.And gamma is the resonance width in FWHM.So from the curve fitting using Lorentzian function,the GDR parameter for red 208 is obtained, something like this.So the GDR parameters of most of the unstable nuclei are tabulated in literature such as the atlas of photonutron cross-sectionwhich is obtained by a phototron annihilation flight photons.So this shows the mass dependence of GDR energy extracted from the Lorentzian curve fittingfor the nuclei with mass larger than 50.So this is plotted on log log scale.The GDR energy decreases with increasing the mass numberand can be expressed by this equation.This has the dependence of A minus to the power of minus one-third and A to the power of one-sixth.So this dependence arrives from that when the displacement of the neutron proton takes place,the reswaring force is proportional to the nuclear radiusand nuclear surface.And the first term becomes more important for heavy nucleibecause the large fraction of the nucleon located at the inner part of the nucleus.So the surface term on the reswaring force becomes less important for heavier nuclei.This is the integrated photo absorption cross-sectionfor the dipole resonance.Pro-section can be written by this equationwhich is proportional to the product of number of neutron protonsdivided by mass number.So this is called Thomas-Reichekun TRK sum rule.So this figure shows the integrated total photoneutron cross-sectionreactive to the TRK sum rule.The TRK sum rule is not exhausted for nuclei with mass number less than 80.So this is because this plot is a photoneutron cross-sectionreactive to the photo absorption cross-section.So as I explained that for light nuclei,the Coulomb force is low.Coulomb force is weak.The cross-section of the charged particle emission isthe emission of the charged particle compete with the neutron emission.So the cross-section of the charged particle emission has to be consideredfor light nuclei.So on the other hand,for heavy nuclei with mass numberlarger than 100,the total photoneutron cross-sectionabsorbs the TRK sum rule.So this is because the heavy nuclei,the Coulomb force is large.The particle emission is inhibited.So that the total photoneutron cross-section is close to the TRK sum rule.So I should note that for heavier nuclei,some data exceeds the TRK sum rule.This is due to the contribution of the method exchange force.So more precisely TRK sum rule should include this collection termand the one plus copper.So for heavy nuclei,copper is known to be 0.1 to 0.2.So in addition to the measurement of photonuclear reaction data,compilation and evaluation of the much effort paid to thecompilation and evaluation of the photonuclear reaction data.There are several photonuclear data bibliography.So some of them are shown here.So these include the reference of the experimental data publishedduring the 40s to 90s.Famous one is X4 database,which is maintained by an international networkof nuclear data center by IAEA.So there are also several overviews of photonuclear reaction data.The famous one is the Atlas of photoneutron cross-sectionobtained with the monoinus photombene frompoitonal annihilation in flight.This includes the photonuclear data,the digital cross-section,and Lorentzian parameters.Varalarm of also published Atlas of giant dipole resonanceparameter and graph of photonuclear reaction cross-section,which is measured by obtained by usingframesolar inpoitonal annihilation in flightand tagged photon.IAEA also prepared the handbook on photonuclear datafor applications for sections and spectra in 2000.Evaluated library for photonuclear reaction data.So there are several libraries publishedduringfrom 1999 to 2014.Most recent one is Tendall 2014,which includesmore than 2600nucleides.For general photonuclear data library,this ispublished in 2004.So after that the photonuclear data were newly obtainedand several updates such as photonuclear reaction model,discrete levels,are carried out.So JAEA group started to update thishotonuclear data library to improve the reliabilityof evaluation,as well as the number ofnucleides included in the library.So they expect to publish new library by theend of next March.The third version includes 181nucleidescalculated by conecalculation code.So there is another expanded version,which includesthe 2074nucleides.Cone is a calculation code dealing withcompound and prachybulium processes.So Dr. Iwamoto is developing thiscalculation code and already evaluatedthese quantities for 74nucleidesfrom zinc to neptunium.This is an example of evaluationfor 0.90.The left figure shows the totalhotoneutron production,the experimental data taken atRibamore andSakurai laboratory are shownwith circle and triangle.So based on the Barman's comment in 1987,Sakurai data is multiplied by 0.88.So the cone evaluation is shown withred line.Other evaluation is also shown withdifferent parts.At the low energy,the evaluations areagreed with each other.So this shows the one-neutronproduction cross-section.And there is some discrepancybetween the gender PD-2004 and the coneevaluation.So this is due to the collection of the cross-section for two-neutronproduction cross-section.So this shows evaluation for Iodine 127.The hotoneutron production cross-sectionis shown in the left figure.Sakurai data is multiplied by 0.8.Evaluation with Kairi iscompared in this spectrum.So there is some discrepancybetween the Kairi and coneevaluation.So this is due to the Kairievaluation is obtained bypitting the original Sakurai data.So this is the evaluation forTamalini 152.Sakurai data is also multiplied by4.88.And the evaluations areagreed with each other except thathigh energy furtherno experiment data uses.So this is for theevaluation forBranium 238.So fission cross-section isshown in theleft figure.So the evaluations areagreed with each otherexcept that low andhigh energy.I mentioned that there isdiscrepancy between theRibamon and Sakurai data.So this shows theone neutron production cross-section for Iodine 127.So Ribamon grouptook the data twicein 198719691987So both the datalower than the Sakurai data.So the other nucleiRibamon data issystematically lower than theSakurai data.So its point is thatthere is some problem on thedetermination of photon fluxneutron efficiencyneutron multiplicity countingwhich is important forneutron cross-sectionmeasurement.I moved to the nexttopics on therecent photon nuclear reactionmeasurement withlaser-compton scatteringgammalase.Quadimonase photon beamcan be generated bycompton scattering betweenlaser photons andelectrons, high energyelectrons.So in the conventionalcompton scattering betweenthe photons andelectrons at the photons lose energygiving their energy toelectrons.But when thephoton collide withhigh energyelectrons.So the photon gained energy fromthe electrons.So this is calledlaser-compton scattering.In thelaser-compton scatteringso the polarizationof thelaser-photonis conserved.So we canobtain thepolarized photon beamin this process.So we can alsochangetune the photon energyby changing theeither theelectron energyor thelaser-wave lengthwhich I shown in the next slide.This is theenergy of LCS photon beam.The energy of LCS photon beamdepends on theenergy oflaser-photon ELand the energy of theelectrons TE.So beta is theelectron velocity relative tothe speed of light.So theCeta L is theincent angle betweenlaser-photon andelectrons.And thescattered angle of LCS photons.So if we assumethe head-tone collision betweentheelectrons and photons,this equation can bewritten into thishome.So here the gammais theelectron energy divided bythe electron restomass.And this equation depends on thescattered angle.So this dependencecan be used tomake aphoton beam.Maximum energy ofthe LCS photon beamis obtained atscattered angle of 0 degreewhich is driven byfour timesgamma squared timesenergy of photons.So we cantune the energy ofthe LCS photons bychanging theelectron energy orlaser-wave length.The strength distribution of LCSphoton beam can becalibrated byprinitinal formula.So this figure shows thedifferential cross-sectionof LCS photonsfor thegenerated by theelectron with energy ofthe LCSphoton laser.So themaximum energy is aboutTMEB.The strength has amaximum at thismaximum photon energyand has anearly a symmetric shape.This shows thestrength,photon strengthas a function ofscattered angle.This is calculated for500MEBand thelaser-wave length of527nm.So themaximum energy is9MEB.So we can see most ofstrength is concentratedinto the forward directionwhich isforward directionwithin thescattered angleof1mL,which isinverse ofLMEB.So this shows theenergy angle correlationof LCSphoton.The energy of LCSphotonis maximum atthe theta of 0°anddecrease withincreasing thescattered angle.So if we definethescattered angleby 4m,the energy photoncan be narrowed.So this shows thehow to makesuch aphoton beamwith such aphoton beam.If we use a collimatorwith 2mm diameterfold,press6m from the collision pointwhich isequal to theenergy widthbecome about 4%.So more preciselythe energy widthof the LCSphoton beamdepends on theelectron beam emittancewhich is related to thebeam size and divergenceof electrons at the collision point.So this shows theLCSGAMB beam lineat the national instituteof advanced industrial science and technologyAISP TsukubaJapan.The laser beamis injected into theelectron storage ringand collide withaccelerated electronsand the LCSphotonis generated intothis direction.So this red collimatoris used to define thescattered angleto make aphoton beam.LCSphotonbeamhas the energybetween 300and800mEband the laser wavelengthis1053nmand 527nmand the laser poweris about 40W.So in this positionthe LCSphotonand 40MEbwith the intensity10 to the 6thper second can be obtained.This shows theenergy distribution of the LCSphoton beammeasured with germanium detector.So themeasured spectrum is shownwith black lines.So we can seea photo piecearound here.So most of the eventis associated withcompton escape event.imperfect energydeposition of the photonin the germanium crystal.In order to estimatethe energy distributionof the LCSphoton beamwe can use a Monte Carlo simulation.So blue lineshows the simulatedenergy spectrum obtained fromthe X5 Monte Carlo simulation code.So the LCSphoton beamthe AISTenergywith is typically5 to 10 percent.Nownext I will showyourphotonutron measurementfor nuclear astrophysics.So there isabout 100elementwith about 300sweve nucleishownwiththe black squaresin this chart of nuclei. Horizontal axis isnumber of neutronand the vertical axis is number of protons.Sonumber of 2,8,20,20,8,50,82 and 126is the magic numberfor nuclei.In the universethe lighter elementare thought to be producedby big one nucleosynthesisand nuclear fusionreactions.So on the other handmost of nucleiheavier than ironwere produced bytwo types ofneutron capture reactionwhich are calledthrow and rapid processes.So throwand rapid meanthat the neutron captureis slowerand fasterthan the beta decay.So this shows the relative abundanceofmedium and heavy elementas a function of the numberof mass.So we can seeseveral peaks in thisfigure.So the abundancepeaks for its process nucleiappear atthe neutron number of50,82and 126so which is themagic numberof the nuclei.So this is due to thesmall neutron capture cross sectionfor magic number nucleiwhich result in thelarge abundance of theseisotopes.So on the other handthe r plus peakat the neutron number of4676and 116which is slightly less thanthe correspondingneutron magic number.So in the r processso these nucleiareproducedby beta decaysafter the production of neutronrich unstable nucleihaving aneutron magic number.So thisabundance peaksobservation of thisabundance peaksare consistentwith theshell model interpretationand for evidencefor the production ofthe medium and heavy elementin the two neutron capture reactions.This showshow theelement are produced byneutron capture reaction.Stable nuclei are shown withthick squaresand unstable nucleiare shown with thin squares.As shown with green liness processproceed along thestable isotopebyparting the p nucleiwhich are shown withp nucleiso in the r processthe unstableneutron rich nucleiare first produced byrapid neutron capture reactionand thesestable isotopesare produced bybeta decayschain of beta decaysas shown withblue arrows.p nucleiare noton the s process pathbut alsoshould itfor thesestable elementsshown byblack squaresfor the beta decaysthe r processdoes not proceed overthese nucleiso p nucleicannot be producedeither in ther processor r processhoweverthere is35 proton richheavy nucleiwhich cannot be synthesizedin the neutron capture reactionso thesenuclear calledp nucleianother future of p nucleiis its small abundanceabundance relative to4.1 to0.1%several idea for the production of p nucleibutit is likely that the mostheavy p nucleiare produced byhottodis integrationreactionsuch as theyamma n,yamma p andyamma alpha.so this shows how the p nucleiproduce in these reactionswith the squarecan be produced byyamma n reaction fromthe c nuclei which waspreviously produced inthe s and r processandyamma p and gamma alpha reactionalsoproduceliter p nucleiso this processis calledyamma processtypical conditionof the gamma processtemperature at 2 to 3times 10 to the 9 kand density is10 to the 6lampar square centimeterand timescale is a few secondsso production site islikely oxygen andneutron rich layeror machimesterduring the supernova explosionanother production siteof the p nucleiis a neutrino processsousuallyp nucleilanternum 138canternum 180produce in theoxygen and neonp each layerby newton reactionduring supernova explosionfor theabundance calculationof nuclei including p nucleimore than 10,000sable and unsable nucleireactionso since it is impossibleto measureall reaction ratesexperimentallyreaction rates are usually calculated byusing further fetchexperimental dataof photonuclear reactions are used forthe restrictionof the model parameter such asyamma resonance functionand level densityso practicallyripple is usedwidely usedfor the parameter such asthe optical potentiallevel densityyamma resonance functiondiscrete level, mass and deformationlarge number ofthe photonuclear cross section dataare availableat the giant type of resonance regionbut afterphysically important energyfor production of p nucleiis not identicalto thedial regionso the sterile reaction ratefor production of p nucleican beobtained by the productof photon numberand photonutron cross sectionso photon numberunder the sterile conditionis given byprank distributionin which thenumber of photonsluckily decreased withincrease energy of photonsso on the other handthe photonutron cross sectiondecrease withincreasedecreasing the energy of photonsso the productof this quantitymake a narrowenergy window1 to 2 MeBjust above theneutron separation energyso thethis regionis important forthe production of p nucleithe cross sectionaround the neutron separation energyis very smallso there is no experimental datafor most of nucleisoin order tomeasure this cross sectionit is useful tolcs photon beamwhich haspergemonon energypoton beamuse the lcs photon beamat the AISCto measure thehotonutron cross sectionnear the neutron separation energyso this shows the typicalhotonutrontypical setup forhotonutron measurement at AISCso lcs gamma rayhotonutron targetwhich isplaced at the center ofneutron detectorso this shows theneutron detectordeveloped atKornan Universityin Japanso the detector consists of16volon fluorideneutron counterso this detector covered with2222set of 8detectoris placed at thedouble concentric ringsat the 7 and 10 cmfrom the beam axisthis is thesodium iodinechinchillation counterwhich is used to measure thehoton fluxexample of hotonutron cross sectiondata forTantem 181data taken withlcs photon beamshown withblack squareswhich is compared withpositron annihilation in flightdata taken withlcs photon beamshows the cross sectionvery close tothe7.6 MeBthe7.6 MeBshow the cross section ofTangsten 186 andRenium 187so before this measurementthe dataabove the 9 MeBis known forTangsten 186and there is noexperimentary data forRenium 187we measure the cross sectionvery close to theneutron separation energyfor bothnuclearthis shows thetypical behaviorof theelectric dipole resonance innuclearso this is a giant dipole resonanceso at the tail of thegiant dipole resonancefound inthe neutron rich nucleiso since theclose, since thestrength of this resonanceis small compared tothe giant dipole resonanceso this resonance is calledpigmin dipole resonanceso this shows themeasuredeven strength forred 208taking from theexperimentso extra M1 strengthisobservesat theneutron, around theneutron separation energy of7.5 MeBso this also shows thedifferential cross section forTin 132 taken fromthe inelastic proton scatteringthe top figure shows theE1 strengththe extra M1 strengtharound 9 MeBisobservesin this nucleusthe strength is about 3.2%reactive to the TRKsome ruleso in thepdr,pigmin dipole resonanceproton and neutrons move in phasein nuclear interiorso but at surfaceneutron oscillateagainst the proton andneutron coreso this produceelected dipole strengthmaking apigmin dipole resonancepigmin dipole resonanceis related toformation of theneutron skinso thickness of neutron skincan be estimated bydipole plusabilityso the dipole plusabilityobtained by this equationwhich is the proportion of theabsorption cross sectiondivided by energy ofsquared energy ofpotonso since thedipole plusabilityhas thedependence of this energydependence,low energyE1 strength ismore importantthis shows theabsorption cross sectionmeasured byproton scatteringproton scatteringat rtnp osakaso fromthis measurementthe osa is like thedipole plusability of20.1 cubiccentimeter pere squaredthe correlation betweenneutron skin thickness anddipole plusability waspreviously obtained fromred elixas shown byred elixso based on thiscalculation,theneutron skin thickness of4.156is obtainedfor red 208I think Isock the firstrepture