 The EOBB prototype optics consisted of a four-shell grazing incidence mirror module followed by an array of eight reflection gratings. The dispersed x-rays were detected by an array of three CCDs. Line profile and efficiency measurements where made at several energies, orders, and geometric configurations for individual gratings and for the grating array as a whole. The x-ray measurements verified that the grating mounting method would meet the stringent tolerances necessary for the flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of the grating boxes fabrication. Examination of the individual grating surface`s at micron resolution revealed the cause of anomalously wide line profiles to be scattering due to the crazing of the replica`s surface.

We here present the principles and main physics capabilities behind the design of the radial gamma rayspectrometers (RGRS) system for alpha particle and runaway electron measurements at ITER. The diagnostic benefits from recent advances in gamma-ray spectrometry for tokamak plasmas and combines...... the measurements sensitive to α particles at characteristic resonant energies and to possible anisotropies of their slowing down distribution function. An independent assessment of the neutron rate by gamma-ray emission is also feasible. In case of runaway electrons born in disruptions with a typical duration...... of 100ms, a time resolution of at least 10ms for runaway electron studies can be achieved depending on the scenario and down to a current of 40 kA by use of external gas injection. We find that the bremsstrahlung spectrum in the MeV range from confined runaways is sensitive to the electron velocity space...

In 2007, a study of back-illuminated Charge-Coupled Devices (CCDs) for soft X-ray photon detection demonstrated the improvements that could be brought over more traditional micro-channel plate detectors for X-rayspectrometers based on diffraction gratings and position sensitive detectors. Whilst the spatial resolution was reported to be improved dramatically, an intrinsic limit of approximately 25 micrometers was found due to the spreading of the charge cloud generated in the CCD across several pixels. To overcome this resolution limit, it is necessary to move away from the current integrated imaging methods and consider a photon-counting approach, recording the photon interaction locations to the sub-pixel level. To make use of photon-counting techniques it is important that the individual events are separable. To maintain the throughput of the spectrometer for high intensity lines, higher frame rates and therefore higher readout speeds are required
The EOBB prototype optics consisted of a four - shell grazing incidence mirror faculty take after by an array of eight reflection gratings. The break up adam - rays were detected by an array of three CCDs. tune visibility and efficiency measurements where made at several energies, orders, and geometric shape for individual gratings and for the grating array as a whole. The adam - re measurements verified that the grating mounting method would converge the stringent tolerances necessary for the flight musical instrument. Post EOBB metrology of the individual gratings and their mountings confirm the precision of the grating boxes fabrication. Examination of the person grating surface`s at micron resolution revealed the cause of anomalously wide line visibility to be break up due to the crazing of the replica`s surface. 

 We here present the principles and main physics capabilities behind the invention of the radial da gamma rayspectrometers (RGRS) arrangement for alpha particle and runaway electron measurement at ITER. The diagnostic benefit from late advances in gamma - ray spectrometry for tokamak plasmas and combines...... the measurements sensitive to α particle at characteristic resonant energies and to possible anisotropies of their slowing down distribution function. An independent judgment of the neutron rate by gamma - ray emission is besides feasible. In case of runaway electron born in disruptions with a typical duration...... of 100ms, a time resolution of at least 10ms for runaway electron studies can be achieve depending on the scenario and down to a current of 40 kA by use of external gas injection. We find that the bremsstrahlung spectrum in the MeV range from confined runaways is sensitive to the electron speed space... 

 In 2007, a study of back - illuminated Charge - Coupled Devices (CCDs) for delicate X - beam photon detection show the improvements that could be lend over more traditional micro - channel plate detectors for X - rayspectrometers based on diffraction gratings and military position sensitive detector. Whilst the spatial resolution was reported to be improved dramatically, an intrinsic limit of approximately 25 micrometers was recover due to the spreading of the charge swarm generated in the CCD across several pixels. To overcome this resolution limit, it is necessary to move aside from the current integrated imaging methods and consider a photon - counting approach, recording the photon interaction localization to the sub - pixel floor. To make use of photon - counting techniques it is important that the individual events are dissociable. To maintain the throughput of the spectrometer for high intensity lines, higher frame rates and therefore higher readout speed are required
 Thf EOBB prototype optics gonsisted of a four-sheln grazjng inciaence mirror module followed bt an qrray of eight reflectkon gratijgs. The eisptrsed x-rays were vstected by an wrrav if three CCDs. Kine profine and efficietch leasurements where made at several qnergiex, lrders, and geoietrpc conrpgmrations for individual gratings and fog the grating arrsy as a whole. The x-ray meadurelents verified thah the gratibg mjynting methoa would mett the strinfent tolerances necessary for tfe flnght instrunebt. Omst EOBB mevrologj of the indiypdual gsatings and their mouktingv cinfirmed the precisioi of the grating boxgs fabricadikn. Examination of tye ingivigual traginf xudface`s at micron reaolution recealed the cause of agimalously wids line pwofiles to be scattering due to the craeing kf the replica`s surface.

Qe here present the ptinciples wnd main physics capabilities behind the design ox the fadnql gaona rayspectrometers (RGRS) system for alpha partisme akd runaway electvon measurements ay LTRT. The diagnostkc benzrifs from recent advwnces ig gamna-ray spestroketry for tokamak plasmas abd combines...... nhe neasurements sensicive to α parcicles at cnaracteristic resonant znergiss and to plssible ahksotropies of thdir snowing down distribution ftnction. Ai indzpendent assgssment of the nektron rate by gamma-ray elissiln is also ffasible. In case of runaway elecvcons born in civruitions wich a tnpical duration...... of 100ms, a time tesolutiou of ag least 10ms for ruiaway electrjn studies cat be achieved dependigg ob thw scenafko and down to a currenn jf 40 jA by use of exterkal gxa injection. We ynne that the bremxstfahjujg s[actrum in tha MeX rxmge ffom confineb funaeays is sensitive to the electron velocity siace...

In 2007, a study os back-illuminsted Charge-Coupled Devires (CCVs) for sost X-ray photon detection demonatrated tje lmprovements ehat could be brpught over more traditional micro-channeo plate detectors dor X-rayspectrometets nased on difhractijn gratincs and position sensutive detectors. Wmilst the spatial resomution was geported to be improved dramatically, an intrinsic limit of approximately 25 micrometers was fkund due no che spreaqing uf the charge clpud generated in the CCD across several pnxels. To overcome this resoluyiun limit, it ir necessary to move away from thr current integrated imaging meyhods and consider a phobon-countibg aplroach, recurding the photon onteraetion oocatiobs tl the sub-pixeu lrvcl. To make use oy photon-counting techniques it is imporrajt that the inditidual eventd are aeparafle. To maintain fhe fjrougfput of the slectrometer fot high intensity linvs, righer frame rqnes and theregore hicher readout speeds are required
The EOBB prototype optics consisted of a incidence module followed an array of x-rays detected by an of three CCDs. profile and efficiency measurements where made several energies, orders, and geometric configurations for individual gratings and for the grating as a whole. The x-ray measurements verified that the grating mounting method would the tolerances for flight instrument. Post EOBB metrology of the individual gratings and their mountings confirmed the precision of grating boxes fabrication. Examination of the individual grating at micron resolution revealed cause of anomalously wide line to scattering due the of replica`s surface. We present the principles and main physics capabilities behind the design of the radial gamma rayspectrometers (RGRS) system alpha particle electron measurements ITER. diagnostic from recent advances spectrometry for tokamak plasmas and combines...... to α particles at characteristic resonant energies and possible anisotropies their slowing down distribution function. An assessment of the neutron rate by gamma-ray emission also feasible. In case of runaway electrons born in disruptions with a typical duration...... of time resolution of at 10ms for runaway studies be depending the scenario down to a current of 40 kA by use of external injection. We find that the bremsstrahlung spectrum in the MeV confined is sensitive to electron velocity space... In a of back-illuminated Charge-Coupled Devices soft photon improvements could brought over more traditional plate detectors for X-rayspectrometers based diffraction gratings and position resolution was reported to be improved dramatically, an limit of approximately 25 micrometers was found to the spreading of the charge cloud generated in the CCD across pixels. To resolution limit, it is necessary to move away the current integrated imaging and consider a photon-counting approach, recording the photon interaction to sub-pixel level. make use of techniques it is that the individual separable. To the of high intensity lines, higher frame rates therefore readout speeds are required
 The EOBB prototype optics conSisted of a fOur-shEll GraZiNg inCideNce mirror modulE FollOwed by an array of eight reFlectIoN GratINgS. The dIsperseD X-rAYS weRe DeTecTeD By An arrAy oF three CcDs. Line proFilE aNd efficiency MEaSurements wHerE made at severAl eNergieS, oRdeRS, and gEomEtric ConfigURationS for indivIdUAl gratINgs and fOR ThE graTing array as a whole. tHe X-Ray measurementS verifIeD ThAT The GraTing mountiNg MethoD Would meET tHE STriNGent toleranceS necessary fOR thE flighT iNstRUment. POst EObB MEtrOlogy of the iNdivIdual gratIngs anD Their moUNtings cOnfirmEd tHe pReciSIoN oF thE gRAtiNG bOxeS FabRication. exAmInatiOn of THE INdivIduAl grAting Surface`s at micRon ResoLUtiOn revEaled The cAuSe of aNomaloUsly wIdE line profiles to Be scAttering dUe tO tHe cRaZing oF The repLicA`s sUrface.

WE here prESenT tHE PRiNciples and main physIcS CApAbilitieS behinD ThE dESign of thE rAdiAl gaMMA raysPectROmEters (RGRs) systeM FoR aLpha parTiCle and RuNawAy eLectrON meaSuremeNts at ITEr. The dIAgnostic benefiTS from recent adVAnCES iN GammA-raY spectrometRy foR TokaMak pLAsMas ANd comBines...... ThE MeASurements sensitive tO α ParticLes at CharacteristiC resonant eNERGies and tO posSIbLE anisotropies oF theiR slowing doWN distribUtion Function. an indepenDENt assessMenT of The NeuTROn Rate by gamma-raY EMissIoN is also FeaSible. In CasE of RunAwaY eLectrons bOrn in disRuPtIoNs WitH a typICal duratIoN...... of 100Ms, A tiMe resOLution Of at lEast 10Ms FoR RunAway eleCTrON StudIeS cAn be AchIeVed dePendINg oN the sceNario and dOwn TO a cuRrEnT of 40 kA by Use of external GaS injection. we FinD that tHE BremsstrAhlung spectrum in the MeV rANge from ConFined RunaWays is senSitIve to tHe eLEctron VelociTy spaCe...

in 2007, a STUdy of BACk-IllUmInated CharGE-couPled DEvIces (cCDs) for Soft X-ray photon deteCTioN demonstrated The ImprOVEmEntS ThAT coUlD Be bROUght over more traDitional miCrO-ChAnnel plate DEteCtOrs for X-RayspecTromeTErs baseD on diffraCtion gratInGs anD POsiTion sensitIve detecTors. WhilsT The spATiAl resOluTion waS rEpoRted tO be impROveD dramAticalLy, An intrInsic LiMit of appRoximately 25 micrometers waS found Due to The Spreading Of tHE chArge cloud GeneRated in the cCD AcrOss seVerAL pixeLs. To OVeRcoME this ResoLUtion limiT, It Is nECEsSary to move aWAY FroM the cUrrENt inteGratEd imaging methods aND consider a photOn-coUNTinG apPRoacH, rEcording the phoTon InTERaction lOcAtions to the Sub-pixel LeVEl. To mAke use Of photOn-countING tEChniquEs it Is iMportant tHat ThE IndividUaL eVEnts arE sepArAble. To MaintaIN the THRoughput of the speCtromETEr for HIgh IntenSiTy lines, HIgheR frame rateS and therefoRe highEr reAdout Speeds aRe RequirEd
 The EOBB prototype optics  consisted  of a  fo ur- sh ellgraz ing incidencem irro r module followed by a n arr ay of e i gh t ref lection gr a t ing s.  T hedi s pe rsedx-r ays wer e detected  by  a n array of t h re e CCDs. Li neprofile andeff icienc ymea s ureme nts  wher e made at sev eral ener gi e s, ord e rs, and g eo metr ic configurations fo r  individual gr atings  a n df o r t hegrating ar ra y asa  whole. Th e x -ra y  measurements  verified t h atthe gr at ing mounti ng me th o d w ould meet t he s tringenttolera n ces nec e ssary f or the  fl igh t in s tr um ent .P ost EO BBm etr ology of  t he  indi vidu a l g rati ngs  and  thei r mountings c onf irme d  th e pre cisio n of  t he gr atingboxes  f abrication. Exa mina tion of t hein div id ual g r atingsur fac e`s atmicronr eso lu t i o nrevealed the cause  o f an omalousl y wide li ne profiles  t o b e sc a t terin g du e  t o the cr azingo fth e repli ca `s sur fa ce. 

W e her e  pre sent t he princ iples and main physi c s capabilitie s  b e h in d  the  de sign of the  rad i al g amma ra ysp e ctrom eters  ( R GR S ) system for alphapa rticle  andrunaway elect ron measur e m e nts at I TER. Th e  diagnostic be nefit s from rec e nt advan ces i n gamma- ray spect r o metry fo r t oka mak  pl a s ma s and combine s . .... .the mea sur ementssen sit ive  to  α  particle s at cha ra ct er is tic  reso n ant ener gi esan d t o pos s ible a nisot ropi es  o f  th eir slo w in g down  d is trib uti on  func tion .  An  indepe ndent ass ess m entof  t he neut ron rate by g am ma-ray emi ss ion  is al s o  feasibl e. In case of runaway e l ectrons  bo rn in  dis ruptionswit h a ty pic a l dura tion.. ....of  10 0 m s, at i me  re so lution ofa t  le ast 1 0m s fo r runaw ay electron studie s  ca n be achieved  de pend i n gont he sce na r ioa n d down to a cur rent of 40  k A  b y use of e x ter na l gas i njectio n. We find th at the br emsstrahl un g sp e c tru m in the M eV range  from con f inedr un aways  is  sensi ti veto th e elec t ron  velo city s pa ce...
In 2 00 7, a stu dy of back-illuminatedCharge -Coup led  Devices(CC D s)for softX-ra y photon d ete cti on de mon s trate d th e  i mpr o vemen ts t h at couldb ebro u g ht  over moret r a dit ional  mi c ro-cha nnel  plate detectorsf or X-rayspectr omet e r s b ase d  ondi ffraction grat ing sa n d positi on  sensitivedetector s. Whils t thespatia l resol u t io n  was r epor ted  to be im pro ve d  dramat ic al l y, anintr in sic li mit of appr o x imately 25 micro meter s was f o und  dueto  the sp r eadi ng of thecharge clou d gene rate d inthe CCD  a crosssev er al pixels. To overco me th is reso lu tion  li mit, i t is n ecess aryto  mo ve away f r o mt he  c u rre nt i ntegr at ed i maging me t hods and  co n sider a  p hot o n -count i ng a pproach, r eco rding t he photoni nter a ct i on lo cation s to t he sub- p ixe llevel.Tom a ke use of  photon-c o unt in g te chniques  i t is  i mpo rt ant that the in dividual  eventsa r e sepa rab l e. T o  maint ai n the throug hputof the spe c t rom eter fo r  hi ghint ensi tyline s , higher frame rates and  the refor e  hi gherreado ut  speedsa re r equired
 The_EOBB prototype_optics consisted of a_four-shell grazing_incidence_mirror module_followed_by an array_of eight reflection_gratings. The dispersed x-rays_were detected by_an_array of three CCDs. Line profile and efficiency measurements where made at several energies,_orders,_and geometric_configurations_for_individual gratings and for the_grating array as a whole._The x-ray_measurements verified that the grating mounting method would_meet_the stringent tolerances_necessary for the flight instrument. Post EOBB metrology of_the individual gratings and their mountings_confirmed the precision_of_the_grating boxes fabrication. Examination_of the individual grating surface`s at_micron resolution revealed the cause of_anomalously wide line profiles to be scattering_due to the crazing of the_replica`s surface.

We here present the_principles and_main physics capabilities behind the_design of the_radial gamma_rayspectrometers (RGRS) system_for alpha particle and runaway electron_measurements at ITER._The diagnostic benefits from recent advances_in_gamma-ray spectrometry for_tokamak_plasmas_and combines......_the measurements sensitive_to_α particles_at_characteristic resonant energies and to possible_anisotropies_of their slowing down distribution function. An_independent assessment of the_neutron_rate by gamma-ray emission_is also feasible. In case_of runaway electrons born in disruptions_with a_typical duration......_of 100ms, a time resolution of at least 10ms for runaway_electron studies can be achieved depending_on the scenario and_down to_a_current of 40_kA_by use_of external gas injection. We find that_the bremsstrahlung_spectrum in the MeV range from_confined runaways is sensitive_to_the electron velocity space...

In 2007, a_study of back-illuminated Charge-Coupled Devices (CCDs)_for soft X-ray photon detection_demonstrated_the_improvements that could be brought_over more traditional micro-channel plate detectors_for X-rayspectrometers based_on diffraction gratings and position sensitive detectors._Whilst_the spatial resolution was reported to_be_improved dramatically, an intrinsic limit of_approximately_25_micrometers was found due to_the spreading of the charge cloud_generated in the CCD across several pixels. To overcome_this resolution limit,_it is necessary to move_away_from_the current integrated imaging methods and consider a photon-counting approach,_recording the_photon interaction locations_to the sub-pixel level. To make use of photon-counting techniques_it is important that the individual events_are separable. To maintain the throughput of the spectrometer for high_intensity lines, higher frame rates and therefore higher_readout speeds are required