Kyoto Area Neutron Source Activity

Transcription

1 Kyoto Area Neutron Source Activity Satellite Pulsed Tiny Neutron Source Y.Iwashita, M.Ichikawa, M.Yamada, H.Tongu, T.Nagae, T.Tanimori, H.Fujioka, K.Imai - Kyoto University H.M.Shimizu - KEK 1

2 Background (skipped) Why Satellite? Big Facility Irony Flexibility, Usability, Availability, Freedom, etc. Education, Incubation of Ideas Excavation of needs, potential users... Satellite Pulsed Tiny Neutron Source 2

3 Photon Brilliance Photon Case Spring-8 SR from Soft X-ray Undulator Spring-8 SR from Wiggler Sun Spring-8 SR from Undulator Spring-8 SR from BM ROTARY ANODE TYPE X RAY TUBE Medical X RAY TUBE :Solar Mass ~ Earth /Pallas~10 10 Big Facility Tiny Source 3

4 Network beyond Satellite? Collaborations N 2!! Makes all neutronians happy! 4

5 Activity at Kyoto

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8 Uji Campus 8

9 Institute for Chemical Research Accelerator Laboratory 100MeV e-linac 300MeV e-sring Ion Ring 7MeV p-linac 9

10 ICR 7MeV Proton Linac RFQ-2MeV DTL-7MeV <180pps, 50µs duty <~1% 2MeV±1% L5773 x 2 (L3403) 10

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12 Main Campus at Sakyo Tandem Building 12

13 8MV Tandem van de Graaff at Faculty of Science Prof. T.Nagae The spokesman. Prof. K.Imai has retired this March.

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15 Layout as of Tandem H course G course F course Beam Dump Production Target VCN-f-SANS? N 3.5MeV 3.5MeV p-linac 10m

16 Specifications 3.5MeV, <15mApk, <100µAave. <100Hz, <0.1ms, duty <1%, Beam Power < 0.35kW Compact < 4m low energy less shield and moderator gain neutron flux plinac will be installed this year. Hope further progress (in budget?). 16

17 Li(p,n) Be(p,n) Neutron yield M.R. Hawkesworth, Neutron Radiography: Equipment and Methods, Atomic Energy Review 15, No. 2, , R.W.Hamm, Proc. SPIE 4142 (2000) n µc -1 = n/(µa s) ~ mA ave 3.5MeV x 0.1mA=350W Low Neutron Energy 1µC = 6x10 12 p 2x10 9 n/µc -1 one n / 3000 p 17

18 How weak? Effective thermal neutron flux n/cm 2 /s X-10 CP-2 NRX 350mCi Ra-Be source MTR NRU HFIR HFBR ILL ZINP-P' WNR 10 0 Chadwick IPNS ISIS FRM-II SNS SINQ Education ZINP-P Incubation CP-1Component R&D Bercray 37" cyclotron Frontier Study optics/detectors (UCN preparation) better than History of neutron sources. Updated from Ref. [4]. 18

19 VCN-f-SANS VCN -focusing- SANS using modulating PMSx lens 19

20 q = 4π sinθ, k f 2θ q λ k i d = 2π q, 2θ λ d Particles 1. Size(rotating radius) 2. Form (sphere/clinder/ ) 3. Surface structure Neutron s features sensitivity to light elements e.g. H, Li, C, N, O, SAXS magnetism ferro-, antiferro-, spin glass excitations e.g. atomic motion (vibration, libration, diffusion, ) 20

21 VCN-f-SANS? q = 4π sinθ λ ex. q=0.031å -1 (micell of Pluronic) 2θ[º] v[m/s] E[meV] Cold Neutron 5Å Very Cold Neutron 40Å Cold Neutron (CN) + small θ Very CN + large θ on-sample focusing is applicable small size sample 21

22 VCN-f-SANS B = 1 2 g'r2, g'; sextupole field gradient 22

23 VCN-f-SANS Permanent Magnet size ID=15mm OD=80mm Inner: 18 sections Outer: 12 sections 23

24 VCN-f-SANS Synchronization between rot-pmsx and pulsed VCN ToF method Å G' [T/m 2 ] 38Å y = 2.2*cos((m0/30-m1)*pi)+3... íl ÉGÉâÅ[ m ÉJÉCÇQèÊ NA R NA 60ms m/s 28-48Å 48Å 1Å step Time [ms] 24

25 VCN-f-SANS Focusing Test: Beam size Well Synchronized Off Synchronization Caution: different scales! 25

26 ( a+b=260mm c=2265mm ( d=2265/2565mm e=100/465mm Δλ/λ = 6.8±1.5% 26

27 non-ionic polymeric surfactants ; the water soluble triblock copolymer temperature [Cº] Drawings : Jyotsana Lal (ANL) private communications 27

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29 Δq=0.001Å -1 q min Å -1 q max Å -1 VCN-SANS 100mm VCN-SANS 465mm (0.3) VCN- SANS 100mm VCN- SANS 465mm (0.3) SAND SAND (IPNS)

30 VCN-f-SANS Future Plan 30

31 VCN-f-SANS Scaling Laws 1) Lens focal strength is proportional to (lens aperture) -2 x (lens length) 2) Solid angle of the lens aperture is proportional to (focal strength) -2 3) The total distance is scaled as (focal strength) -1 4) The focal length is proportional to (wavelength) -2 5) Rep. rate of the chopper can increase for the shorter total length. When we use three set of the same PMSx, the total length would be 5/3m, which is less than 2m (not 5m). 31

32 VCN-f-SANS Figure of Merit 32

33 Concluding Remarks PL will be delivered by the end of Dec Will help to enhance the neutronian's activities: Education, Incubating new ideas, etc. PECRIS R&D is on going. (Far upstream) f-sans with VCN can be very short and handy. rot-pmsx version is under investigation. just a poor playing words: Ultra Cold Accelerator based Natural Science 33

34 Thank you! 34

35 Appendix 35

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37 Cross-section of H + n (from JENDL-3.3 [2]) b Cross Section [barn] Elastic Capture 1MeV n Energy [ev]

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