Proceedings of the 10th Annual Meeting of Particle Accelerator Society of Japan (August 3-5, 2013, Nagoya, Japan)

2 ݁থ‫ܕ‬ύϥϝτϦοΫ X ઢ‫͚͓ʹݯ‬ΔμΠϠϞϯυ୯݁থͷࢼ‫ݧ‬TEST OF DIAMOND SINGLE CRYSTALS IN THE PARAMETRIC X-RAY SOURCEBASED ON A DOUBLE-CRYSTAL SYSTEM
ૣ઒‫∗ ࢙ګ‬A) ɺ࣢ੴਸ B) ɺੴ‫ڮ‬௚໵ B) ɺૣ઒‫ ݐ‬A) ɺҴֶ֞ A) ɺதඌ‫ ࠤܓ‬A) ɺ໺্ҍࢠ A) ɺ‫ڥ‬෢ࢤ A) ɺࠤ౻༐ C) ɺాத ढ़੒ A)

Yasushi Hayakawa∗ A) , Takashi ShizukuishiB) , Naoya IshibashiB) , Ken HayakawaA) , Manabu InagakiA) ,Kesuke NakaoA) , Kyoko Nogami A) , Takeshi Sakai A) , Isamu SatoC) , Toshinari TanakaA)
A)
Laboratory for Electron Beam Research and Application, Institute of Quantum Science, Nihon University,Narashinodai 7-24-1, Funabashi 274-8501, JapanB)
Department of Radiology, Nihon University School of Medicine, Oyaguchi Kami-cho 30-1,
Itabashi-ku, Tokyo 173-8610, JapanC)
Advanced Research Institute for the Sciences and Humanities, Nihon University, Goban-cho 12-5,
Chiyoda-ku, Tokyo 102-8251, Japan

Abstract
Diamond single crystals that are commercially available were tested for a double-crystal system of the X-ray source
based on parametric X-ray radiation (PXR) at the Laboratory for Electron Beam Research and Application (LEBRA),
Nihon University. Since a diamond crystal has a smaller spacing of crystal planes than a silicon crystal, higher energy
X-rays can be obtained from the diamond crystal as a PXR radiator at the same Bragg angle. Although the size of thediamond single crystals used in this experiment was not sufﬁcient for the 2nd crystal of the LEBRA-PXR source, a tunable
PXR beam from the diamond crystal was successfully observed and X-ray imaging was carried out using the PXR beamup to 60 keV. When the propagation distance between the sample and the detector was 4 m, the image contrast improved
probably due to the propagation-based phase-contrast effect. Except the problem on the target destruction, the result
suggests that diamond crystals have good properties as a radiator for high energy PXR.

1.

Ϊʔ h̄ω ͸ɺ͸͡Ίʹ೔ຊେֶిࢠઢར༻‫ࢪڀݚ‬ઃ (LEBRA: Laboratory forElectron Beam Research and Application) Ͱ͸ɺ125 MeVిࢠϦχΞοΫΛར༻ͨ͠ύϥϝτϦοΫ X ઢ์ࣹ(PXR: parametric X-ray radiation) Λ‫ݪ‬ཧͱ͢Δ X ઢ‫ݯ‬Λ։ൃ͠ɺӡ༻͍ͯ͠Δ [1] ɻ͜Ε·Ͱʹɺճં‫ڧ‬ௐΠϝʔδϯάʹ୅ද͞ΕΔ X ઢҐ૬ίϯτϥετΠϝʔδϯά΍ɺ෼ࢄ‫ ܕ‬X ઢ‫ٵ‬ऩඍࡉߏ଄෼ੳͱ͍ͬͨԠ༻ʹ͓͍ͯ੒Ռ͕ಘΒΕ͍ͯΔ [2, 3] ɻLEBRA-PXR ઢ‫ݯ‬͸ɺిࢠϏʔϜ͕রࣹ͞Εͯ PXR ͷ์ࣹ‫ͳͱݯ‬Δλʔήοτ݁থͱɺൃੜͨ͠ PXR ϏʔϜΛःณนͷ؏௨޸Λ௨ͯ͠༌ૹ͢ΔͨΊͷ൓ࣹ༻݁থͷ 2 ͭͷ݁থͰߏ੒͞Ε͍ͯΔɻޮ཰ྑ͘൓ࣹ༻ୈ 2 ݁থͰ PXR ϏʔϜΛճં͢ΔͨΊʹ͸ɺ2 ͭͷ݁থΛ‫׬‬શ݁থͷಉ݁͡থ
໘Ͱଗ͑Δඞཁ͕͋Δɻ݁থͷ‫׬‬શੑ΍ೖखՄೳͳ݁থαΠζͷ੍໿΋͋ͬͯɺ͜Ε·Ͱ͸γϦίϯ୯݁থΛ༻͍͖ͯͨɻඇৗʹ‫׬‬શੑͷߴ͍γϦίϯ݁থΛ঎‫ۀ‬తʹೖख͢Δ͜ͱ͕ՄೳͰɺͦͷ࢖༻ʹΑΓߴ͍ۭؒίώʔϨϯεΛ༗͢Δ PXR ϏʔϜ͕ಘΒΕ͍ͯΔɻ

PXR ͷ X ઢ‫ͯ͠ͱݯ‬ͷେ͖ͳಛ௃ͱͯ͠ɺൃੜ͢ΔX ઢͷΤωϧΪʔ (೾௕) ͕ిࢠϏʔϜͷΤωϧΪʔʹ΄ͱΜͲґଘ͠ͳ͍͜ͱ͕‫͛ڍ‬ΒΕΔɻೖࣹిࢠͷΤωϧΪʔͱӡಈྔɺ଎౓ΛͦΕͧΕ E, p, v ͱ͢Δͱɺ୯ҐϕΫτϧ Ω ʹԊͬͨํ޲ʹ์ࣹ͞ΕΔ PXR Τωϧ∗ yahayak@lebra.nihon-u.ac.jph̄ω ≈ h̄ω

 p c2h̄c|g·v|
Ω−g ·=,cEc − v·Ω(1)ͱද͞ΕΔɻ͜͜Ͱɺg ͸์ࣹ‫ͳͱݯ‬Δ݁থͷ‫ࢠ֨ٯ‬ϕΫτϧͰ͋Δɻೖࣹిࢠ͕े෼ʹ૬ର࿦తͰ͋Ε͹ɺgΛબͿ͜ͱʹΑΓ PXR ͷΤωϧΪʔΛ੍‫͢ޚ‬Δ͜ͱ͕Ͱ͖Δɻ௨ৗͷ X ઢճંʹ͓͚Δ Bragg ֯ʹ૬౰͢Δɺ݁থ໘ͱిࢠͷ଎౓͕੒֯͢Λม͑Δ͜ͱʹΑΓɺඇৗʹ޿͍ΤωϧΪʔൣғͷ X ઢΛൃੜͤ͞Δ͜ͱ͕‫ݪ‬ཧతʹ͸Ͱ͖Δɻ͔͠͠ͳ͕ΒɺLEBRA-PXR ઢ‫ݯ‬ͷ৔
߹ɺ2 ݁থγεςϜͷ૷ஔ্ͷ੍໿ͷͨΊʹ Bragg ֯ͷൣғ͕ 5.5◦ ∼ 30◦ ʹ੍‫͞ݶ‬Ε͓ͯΓɺ͜Ε͕ൃੜՄೳͳ PXR ͷΤωϧΪʔൣғΛ੍໿͍ͯ͠Δ [4] ɻ౰ॳ͸݁থ໘ͱͯ͠ Si(111) ͷΈΛ༻͍͍ͯͨͨΊɺൃੜՄೳͳ
PXR ͷൣғ͸ 4∼20 keV ʹ‫ݶ‬ΒΕ͍͕ͯͨɺΑΓߴ࣍ͷ݁থ໘Ͱ͋Δ Si(220) ໘Λ༻͍Δ͜ͱʹΑΓɺ34 keV·Ͱͷ X ઢͷൃੜ͕Մೳͱͳͬͨ [5] ɻࣜ (1) ʹ͋ΔΑ͏ʹɺ݁থ໘ִ͕ؒ‫͕ํ͍ڱ‬େ͖ͳBragg ֯Ͱߴ͍ΤωϧΪʔͷ X ઢΛൃੜͤ͞Δ͜ͱ͕Ͱ͖Δɻͭ·Γɺ֨ࢠఆ਺ͷখ͞ͳ݁থͷํ͕ɺX ઢΤωϧΪʔͷߴΤωϧΪʔԽʹ͸༗རͰ͋ΔɻμΠϠϞϯυ݁থͱγϦίϯ݁থ͸݁থߏ଄͸ಉ͡μΠϠϞϯυߏ଄ͱͳ͍ͬͯΔ͕ɺ֨ࢠఆ਺͸μΠϠϞϯυ͕ 3.56 ÅɺγϦίϯ͕ 5.42 Å Ͱ͋ΔͨΊɺಉ͡‫ز‬Կ৚݅ͳΒ͹μΠϠϞϯυͰൃੜ͢Δ PXR ͷΤωϧΪʔ͸γϦίϯʹΑΔ΋ͷͷ໿ 1.5 ഒͱͳΔɻՃ͑ͯɺμΠϠϞϯυ݁থ͸੍ಈ์ࣹʹΑΔ์ࣹଛࣦ͕গͳ͘ɺ೤తʹ΋༥఺͕ߴ͘

- 1221 -Proceedings of the 10th Annual Meeting of Particle Accelerator Society of Japan (August 3-5, 2013, Nagoya, Japan)೤఻ಋ཰΋ඇৗʹྑ͍ͱ͍͏ɺλʔήοτࡐ࣭ͱͯ͠༗
རͳಛੑΛඋ͍͑ͯΔɻྺ࢙తʹ΋ੈքͰॳΊͯ PXRͷ‫؍‬ଌʹ੒ޭ࣮ͨ͠‫Ͱݧ‬͸μΠϠϞϯυ݁থ͕༻͍ΒΕ͓ͯΓɺ‫͔͘ݹ‬Β PXR ์ࣹ‫ʹݯ‬దͨ͠෺࣭Ͱ͋Δͱೝࣝ͞Εͯ͸͍ͨ [6] ɻ͔͠͠ͳ͕ΒɺLEBRA-PXR ઢ‫ݯ‬ͷ 2 ݁থγεςϜʹ͸൓ࣹ༌ૹ༻ʹେ͖ͳαΠζͷ‫׬‬શ݁থ͕ඞཁͳͨΊɺμΠϠϞϯυΛ PXR ์ࣹ‫ʹݯ‬࠾༻͢Δͷ͸ࠔ೉Ͱ͋ͬͨɻ໘ͷ࢖༻͸ൃੜ͢Δ PXR ͷྔ΍ୈ 2 ݁থʹ͓͚Δ൓ࣹ཰ʹ͍ͭͯ͸ෆརͳ৚݅Ͱ͋Δɻྫ͑͹ (220) ໘ͱൺ΂
ͯΔͱɺ(400) ໘Λ࢖ͬͯ LEBRA-PXR ઢ‫͔ݯ‬ΒऔΓग़ͤΔ‫౓ڧ‬͸ɺಉ͡ X ઢΤωϧΪʔʹରͯ͠ 1/3 ∼ 1/4ఔ౓ʹͳΔͱ༧૝͞ΕΔɻ͔͠͠ͳ͕ΒɺμΠϠϞϯυ୯݁থͷ৔߹͸݁থαΠζͷ੍໿͕େ͖͍ͨΊɺࢼ‫ݚݧ‬‫ͯ͠ͱڀ‬͸ X ઢྔʹ͍ͭͯ͸ଥ‫͢ࢪ࣮ͯ͠ڠ‬Δ͜ͱʹ
ͨ͠ɻ

2.

3.

μΠϠϞϯυ୯݁থϓϥζϚ CVD ๏Ͱ੡࡞͞ΕΔଟ݁থͷμΠϠϞϯυ݁থ൘͸ൺֱతେ͖ͳ΋ͷ͕ೖखՄೳͱͳ͕ͬͨɺ୯݁থͷਓ޻μΠϠϞϯυ͸௒ߴѹ๏Ͱͷ߹੒͕ඞཁͰɺେ͖ͳαΠζͷ݁থͷೖख͸ٕज़໘Ͱ΋ɺ‫ࡁܦ‬໘Ͱ΋ࠔ೉Ͱ͋ͬͨɻ͔͠͠ͳ͕Βۙ೥ɺ1 cm ࢛ํఔ౓ͷେ͖͞ͷ୯݁থ͕ટ൫ͷόΠτͳͲͷ༻్Λ૝ఆͯ͠঎඼Խ
͞ΕΔΑ͏ʹͳΓɺൺֱత҆ՁʹೖखՄೳͱͳͬͨɻࠓճɺࢼ‫ݧ‬తʹॅ༑ి޻੡ͷਓ޻μΠϠϞϯυ୯݁থ (঎඼໊: εϛΫϦελϧ) Λಋೖ͠ɺPXR ઢ‫ݧࢼͯ͠ͱݯ‬͢Δ͜ͱʹͨ͠ɻෆ७෺ͱͯ͠஠ૉ͕ൺֱతଟ͘ೖ͍ͬͯΔͨΊɺԫ৭͍৭Λ͍ͯ͠Δɻࠓճ࢖༻ͨ͠μΠϠϞϯυ݁থͷಛੑΛ Table 1 ʹࣔ͢ɻ

Table 1: Characteristics of synthetic diamond single crystal
Diamond type

type Ib

Lattice constant

3.567 Å (25◦ C)

Density

3.515 g/cm3 (25◦ C)

Impurity (Nitrogen)1 ∼ 102 ppm

Electric resistivity

1014 Ω·m

Thermal conductivity< 2000 W/m·K

Crystal dimension
Target crystal:

5 mm × 5 mm × 1 mmt

2nd crystal:(6∼7 mm)2 × 2 mmt

Main crystal face direction(100)͜͜Ͱ໰୊ͱͳΔͷ͕ɺ൓ࣹ༻ୈ 2 ݁থͷαΠζͰ
͋ΔɻLEBRA-PXR ઢ‫Ͱݯ‬͸ PXR ͷ༌ૹϥΠϯ͕ిࢠϏʔϜϥΠϯ͔Β 200 mm ཭Εͯฏߦʹઃஔ͞Ε͓ͯΓɺBragg ͕֯ θB ͷͱ͖ͷλʔήοτ݁থ-ୈ 2 ݁থؒͷ‫ ཭ڑ‬L ͸ L = 200/ sin 2θB [mm] ͱͳΔɻPXR ΋ଞͷ૬ର࿦తͳిࢠʹΑΔ์ࣹͱಉ༷ʹɺ1/γ = me c2 /E(me : ిࢠ࣭ྔ) ʹൺྫͨ֯͠౓޿͕ΓΛ࣋ͬͨԁਲ਼ঢ়ͷ์ࣹͱͳΔͨΊɺBragg ͕֯খ͘͞ͳΔͱୈ 2 ݁থͷͱ
͜ΖͰͷ PXR ϏʔϜαΠζ͕େ͖͘ͳΓɺ࣮ࡍʹ൓ࣹͯ͠༌ૹͰ͖Δ X ઢྔ͕݁থͷαΠζʹ‫͘ڧ‬ґଘͯ͠
͠·͏ɻ‫ࡏݱ‬ͷγϦίϯ୯݁থΛ࢖༻͢Δ‫Ͱܥ‬͸ɺୈ 2݁থͱͯ͠ 120 mm × 37 mm × 5 mmt ͷαΠζͷ΋ͷΛ༻͍͍ͯΔɻμΠϠϞϯυ݁থ΋ୈ 2 ݁থͱͯ͠͸ඪ४඼ͷϥΠϯφοϓʹ͋Δ࠷େͷ΋ͷΛબΜ͕ͩɺͦΕͰ΋γϦίϯ݁থͷ 1/100 ‫ڧ‬ͷ໘ੵʹ͔͠ͳΒͳ͍ɻ͜ͷͨΊɺBragg ͕֯େ͖ͯ͘΋ΤωϧΪʔͷߴ͍ PXR
͕ൃੜ͢ΔΑ͏ʹ࣍਺ͷߴ͍݁থ໘ΛબΜͰ༻͍Δ͜ͱʹ͠ɺඪ४඼ͰͷೖखੑΛߟྀͯ͠ (400) ໘Λ࠾༻ͨ͠ɻ͜ͷ໘ͷ৔߹ɺ40 keV, 50 keV, 60 keV ʹରԠ͢ΔBragg ֯͸ͦΕͧΕ 9.9◦ , 7.9◦ , 6.6◦ ͱͳΔɻ࣍਺ͷߴ͍࣮‫݁ݧ‬ՌࠓճͷμΠϠϞϯυΛ༻͍࣮ͨ‫ݧ‬͸ɺγϦίϯ୯݁থΛ༻͍ͯར༻࣮‫ ʹݧ‬X ઢϏʔϜΛ‫͢څڙ‬Δ৔߹ͱಉ͡ిࢠϏʔϜ৚݅ͰߦΘΕͨɻ۩ମతʹ͸ɺిࢠΤωϧΪʔ 100 MeVɺϚΫϩύϧεిྲྀ 130 mAɺϚΫϩϚϧ
ε෯ 5 μsɺύϧε‫܁‬ฦ͠ 5 pps Ͱ͋ΔɻిࢠϏʔϜฏ‫ۉ‬ిྲྀ͸ɺ͓Αͦ 3 μA ͱ‫ੵݟ‬ΒΕΔɻ

3.1Πϝʔδϯά࣮‫ݧ‬ࠓճ͕ LEBRA-PXR ઢ‫Ͱݯ‬μΠϠϞϯυ݁থΛ์ࣹ‫͢༻࢖ͯ͠ͱݯ‬Δ࠷ॳͷ࣮‫ͨͨͬ͋Ͱݧ‬ΊɺΰχΦϝʔλͷ֯౓Φϑηοτ΍ୈ 2 ݁থ༻ΰχΦϝʔλฒਐҠಈ࣠ͷҐஔύϥϝʔλͳͲʹ͍ͭͯͷલྫ͕ແ͘ɺ޿͘ύϥϝʔλεΩϟϯΛߦͬͯୈ 2 ݁থͰͷճં‫ۂ‬ઢͷϐʔΫΛ‫͚ͭݟ‬Δඞཁ͕͋ͬͨɻ30–40 keV ෇ۙͰ୳ࡧͨ͠
ͱ͜Ζɺୈ 2 ݁থͷճં‫ۂ‬ઢͱࢥΘΕΔϐʔΫΛൃ‫ݟ‬ͨͨ͠Ίɺ݁থͷ‫Ͳͳ֯ڼ‬Λௐ੔͠ɺSi(220) ͷ৔߹ͱಉ༷ʹ Ag ͷ K ֪‫ٵ‬ऩ୺Λ࢖ͬͯΤωϧΪʔֱਖ਼Λߦ͍ɺΠϝʔδϯά࣮‫ݧ‬Λ։࢝ͨ͠ɻFigure 1 ʹ 40 keV ͷPXR ϏʔϜΛ༻͍ɺ์ࣹ‫ݯ‬ͷλʔήοτ݁থ͔Β 7.3 mԼྲྀͷ X ઢऔΓग़͠૭௚‫݁ͨ͠૾ࡱͰޙ‬ՌΛࣔ͢ɻਤ͔ΒΘ͔ΔΑ͏ʹɺୈ 2 ݁থͷαΠζͷ੍໿ͷͨΊʹX ઢϏʔϜαΠζ͸௚‫ ܘ‬100 mm ͷ X ઢ૭ΑΓখ͘͞ɺ
40 keV ͷ৔߹Ͱ 35 mm×85 mm ఔ౓ͷେ͖͞Ͱ͋ͬͨɻ
·ͨμΠϨΫτϏʔϜࣗମʹ‫౓ڧ‬Ϝϥ͕͋Γɺ݁থͷ‫ۉ‬Ұੑʹؔͯ͠͸γϦίϯ݁থʹൺ΂ͯྼΔ͜ͱ͕ࣔࠦ͞ΕΔɻλʔήοτ݁থɺୈ 2 ݁থͱ΋ʹখ͍ͨ͞Ίɺ݁থͷଆ໘͔Β์ग़͞ΕͨΓɺ‫ʹٯ‬ଆ໘͔Βೖࣹ͢Δ Xઢͷׂ߹͕͔ͳΓଟ͍͜ͱ΋Ө‫͍ͯ͠ڹ‬ΔՄೳੑ΋͋ΔɻϏʔϜͷӈ্ʹަ఺Λ࣋ͭෳ਺ͷઢঢ়ͷ໛༷͕‫ݟ‬
͑Δ͕ɺ͜Ε͸γϦίϯ݁থͷ৔߹ʹ΋‫ݟ‬ΒΕΔ΋ͷ
Ͱɺ݁থͷܽؕʹΑΔτϙάϥϑͱߟ͑ΒΕΔɻ·ͨɺFigure 1: The results of X-ray imaging for the direct beam(left) and a laser pointer (right) using the 40-keV PXRbeam. Each exposure time was 5 min using an imaging
plate (IP).

- 1222 -Proceedings of the 10th Annual Meeting of Particle Accelerator Society of Japan (August 3-5, 2013, Nagoya, Japan)

Fig. 1 ͷӈਤ͸ࢼྉͱͯ͠খ‫ܕ‬ͷϨʔβϙΠϯλΛࡱ૾ͨ͠΋ͷͰ͋Γɺ୯ 4 ‫ిס‬஑͕ೖ͍ͬͯΔͷ͕Θ͔Δɻ͜ΕΒͷը૾͸‫ݕ‬ग़‫ͯ͠ͱث‬ΠϝʔδϯάϓϨʔτ (IP)Λ༻͍ɺࡱ૾࣌ؒ 5 ෼ͰಘΒΕͨ΋ͷͰ͋Δɻ
ࡱ૾࣌ؒΛ 15 ෼ʹ৳͹ͯ͠ X ઢಁա૾ͷऔಘΛࢼΈͨ݁ՌΛ Fig. 2 ʹࣔ͢ɻ͜ͷଌఆ͸‫ݕ‬ग़‫͋Ͱث‬Δ IP Λ
PXR ग़ྗ૭௚‫ʹޙ‬ஔ͍ͯߦͬͨͨΊɺμΫτετϦʔϛϯάͰӡ͹Εͨ௿ΤωϧΪʔࢄཚ X ઢͷӨ‫ڹ‬Λड͚͍ͯΔɻ·ͨɺPXR ͷΤωϧΪʔΛ 50 keV ʹ্͛ͯऔಘͨ݁͠Ռ΋ಉ༷ʹ Fig. 3 ʹࣔ͢ɻΤωϧΪʔ͕ߴ͘ͳͬͯಁաྗ͕૿ͨ͠൒໘ɺୈ 2 ݁থͷαΠζෆ଍͕‫ݦ‬ஶͱͳͬͯճંͰ༌ૹͰ͖Δׂ߹͕খ͘͞ͳͬͨ͜ͱ͕෼͔Δɻͳ͓ɺX ઢͷΤωϧΪʔʹ͍ͭͯ͸ 40 keV
͸ Ce ͷ K ֪‫ٵ‬ऩ୺ (40.444 keV) Λɺ50 keV ͸ Gd ͷK ֪‫ٵ‬ऩ୺ (50.239 keV) Λ༻͍ͯ֬ೝͨ͠ɻPXR intensity [a.u.](a)target crash?

0.02

0.01

00shutter close

5001000

1500

Time [s]PXR intensity [a.u.](b) 0.1
0.08
0.06
0.04
−0.1

00.1

0.2

2nd crystal angle [deg.]

Figure 2: The results of X-ray imaging for a laser pointer(left) and a mouse device (right) using the 40-keV PXR
beam. Each exposure time was 15 min using an IP.

Figure 4: (a) Discontinuous and irreversible trip of the PXR
intensity recorded at 34 keV. (b) Comparison between therocking curves at the 2nd crystal before and after the intensity trip.
ʹׂΕɺ෦෼తʹଟ݁থతʹͳͬͯୈ 2 ݁থͷճં৚݅Λຬͨ͞ͳ͘ͳΔׂ߹͕૿͑ͨ݁Ռͱਪଌ͞ΕΔɻ݁থͷഁଛ͕‫ݪ‬Ҽͱߟ͑ͯɺՃ଎‫ث‬ͷεςΞϦϯά΍ΰχΦϝʔλΛௐ੔ͯ͠ిࢠϏʔϜ͕౰ͨΔՕॴΛͣΒ͢͜ͱʹΑΓɺPXR ‫౓ڧ‬͸͋Δఔ౓͸ճ෮ͨ͠ɻ͔͠͠ͳ͕ΒɺҰ౓ُ྾ͷೖͬͨμΠϠϞϯυ݁থ͸ׂΕ΍͘͢ͳΔΑ͏Ͱ୹࣌ؒͰಉ༷ͷࣄ৅͕ൃੜ͠ɺಉ͡Α͏ͳରॲΛ‫܁‬Γฦ͢͜ͱͱͳͬͨɻҰํɺಥൃతͰ͸ͳ͘ঃʑʹ PXR ‫ݮ͕౓ڧ‬গ͍ͯ͘͠Α͏ͳ‫ݱ‬৅͸ಛʹ‫؍‬ଌ͞Εͳ͔ͬͨɻ

3.3
Figure 3: The results of X-ray imaging for a laser pointer(left) and a mouse device (right) using the 50-keV PXR
beam. Each exposure time was 15 min using an IP.
3.2݁থଛইͱ X ઢͷෆ҆ఆੑΤωϧΪʔબ୒୯৭ X ઢΠϝʔδϯάͷ࣮‫ʹݧ‬͸੒ޭ͕ͨ͠ɺλʔήοτ݁থͷഁଛʹ‫ى‬Ҽ͢ΔͱࢥΘΕ
Δ X ઢͷෆ҆ఆੑʹૺ۰ͨ͠ɻFigure 4(a) ͸ PXR ΤωϧΪʔ 34 keV ͷ࣌ʹ‫ه‬࿥͞Εͨɺෆ࿈ଓతͰෆՄ‫ٯ‬తͳ PXR ‫౓ڧ‬ͷมԽͰ͋Δɻ͜ͷॠؒతͳมԽҎ֎͸໨ཱͬͨ‫౓ڧ‬มಈ͸‫ݟ‬ΒΕͳ͔͕ͬͨɺͦͷલ‫ޙ‬ͷୈ 2 ݁থʹΑΔճં‫ۂ‬ઢΛൺֱ͢ΔͱɺFig. 4(b) ʹ͋ΔΑ͏ʹ໌͔ʹ‫ۂ‬ઢͷ‫͕ܗ‬มΘ͍ͬͯͨɻ͜Εͱ͸ผʹɺຊདྷ͸γϯάϧϐʔΫͰ͋Δ͸ͣͷճં‫ۂ‬ઢ͕ɺ͖Ε͍ͳμϒϧϐʔΫͱͳ͍ͬͯΔέʔε΋͋ͬͨɻ͜ΕΒͷঢ়‫͔گ‬ΒɺిࢠϏʔϜͷরࣹʹΑͬͯλʔήοτ݁থ͕ಥൃత఻ൖ‫ܕ‬Ґ૬ίϯτϥετΠϝʔδϯάγϦίϯ୯݁থΛ༻͍ͨ PXR ઢ‫Ͱݯ‬͸݁থͷճંΛར༻ͨ͠Ґ૬ίϯτϥετΠϝʔδϯάͰେ͖ͳ੒Ռ͕ಘΒΕ͍ͯΔ͕ɺ͜Εʹ͸λʔήοτ͓Αͼୈ 2 ݁থͱಉ݁͡থ໘Λ΋ͭେ໘ੵͷ෼ޫ݁থ͕ඞཁͱͳΔͨΊɺμΠϠϞϯυ݁থΛઢ‫͢ͱݯ‬Δ৔߹ʹ͸࣮ࢪࠔ೉Ͱ
͋Δɻ͔͠͠ͳ͕Βɺࢼྉ–‫ݕ‬ग़‫ؒث‬ͷ఻ൖ‫཭ڑ‬Λ௕͘ͱΔʹΑΓ X ઢͷ‫ׯ‬বޮՌͰࢼྉͷ‫ڥ‬ք͕‫ڧ‬ௐ͞ΕΔɺ఻ൖ‫ܕ‬Ґ૬ίϯτϥετ๏ͳΒ࣮‫ݧ‬ՄೳͰ͋Δ [7] ɻ࣮‫ݧ‬͸ɺX ઢग़ྗ૭͔Β 4 m Լྲྀʹ‫ݕ‬ग़‫͋Ͱث‬Δ IPΛઃஔ͠ɺࢼྉΛ IP ͷ௚લʹஔ͍ͨ৔߹ (఻ൖ‫ ཭ڑ‬0 m)
ͱ X ઢ૭௚‫ʹޙ‬ஔ͍ͨ৔߹ (఻ൖ‫ ཭ڑ‬4 m) Ͱൺֱͨ͠ɻ
ઢ‫͋Ͱݯ‬Δλʔήοτ݁থ͔Β X ઢ૭·Ͱ͸ 7.3 mɺIP·Ͱ͸ 11.3 m ͱͳΔͨΊɺ఻ൖ‫ ཭ڑ‬4 m ͷ૾͸఻ൖ‫ڑ‬
཭ 0 m ͷ૾ͷ໿ 1.5 ഒͷ֦େ૾ͱͳΔɻFigure 5 ͸ PXRΤωϧΪʔ 40 keV Ͱͷ࣮‫݁ݧ‬ՌͰɺ্͕఻ൖ‫ ཭ڑ‬0 m
ͷ૾ͰԼ͕఻ൖ‫ ཭ڑ‬4 m ͷ૾Ͱ͋ΓɺͦΕͧΕ෦෼తʹ֦େͨ͠૾Λӈଆʹఴ෇͍ͯ͠Δɻ఻ൖ‫ ཭ڑ‬4 m ͷ- 1223 -Proceedings of the 10th Annual Meeting of Particle Accelerator Society of Japan (August 3-5, 2013, Nagoya, Japan)͜ͱ΋ߟྀ͢Δͱɺ͜ͷࢹೝੑͷ޲্͸఻ൖ‫ܕ‬Ґ૬ίϯτϥετͷޮՌʹΑΔ΋ͷͱࢥΘΕΔɻ͜ͷ݁Ռ͸ɺ඼࣭ͷྑ͍μΠϠϞϯυ୯݁থΛ༻ҙ͢Δ͜ͱ͕Ͱ͖Ε͹ɺ40 keV Ҏ্ͷ X ઢΤωϧΪʔྖҬʹ͓͍ͯ΋ۭؒίώʔϨϯτͳ X ઢϏʔϜ͕ൺֱత༰қʹಘΒΕΔɺͱ͍͏͜ͱΛ͍ࣔࠦͯ͠Δɻ

3.4

60 keV-X ઢൃੜςετҰ࿈ͷμΠϠϞϯυ݁থΛ༻͍࣮ͨ‫ݧ‬ͷ࠷‫ͯ͠ͱޙ‬ɺ
60 keV ͷ X ઢͷൃੜΛࢼΈͨɻ‫ʹط‬λʔήοτ݁থͷྼԽ͕૬౰ਐΜͩঢ়ଶͰͷ࣮‫͋Ͱݧ‬Γɺ·ͨ‫ݱ‬༗ͷ‫ݕ‬ग़‫ث‬ͷ‫͕౓ײ‬ඇৗʹ௿͘ͳΔΤωϧΪʔྖҬͰ͋ΔͨΊɺ·ͱ΋ʹ X ઢͷϞχλϦϯά‫ܭ‬ଌ͕Ͱ͖ͳ͍ঢ়ଶͰͷଌఆͰ͋ͬͨɻPXR ൃੜ૷ஔͷΰχΦϝʔλͷύϧε࠲ඪͷਫ਼౓Λ৴༻͠ɺPXR ΤωϧΪʔ 61 keV ʹ૬౰͢
Δ Bragg ֯ 6.5◦ ʹ֯౓Λ߹Θ͚ͤͨͩͰɺϞχλʔ͠ͳ͕Βͷௐ੔Λ͠ͳ͍·· IP Λ࢖ͬͨࡱ૾ΛࢼΈͨɻ
·ͨɺୈ 2 ݁থͷαΠζෆ଍͕ΑΓ‫ݦ‬ஶʹͳΓɺ༌ૹՄೳͳϏʔϜαΠζ͕͞Βʹখ͘͞ͳΔͨΊɺPXR ϏʔϜαΠζ͕ 1.5 ഒʹ֦େ͞ΕΔ X ઢग़ྗ૭͔Β 4 m Լྲྀʹ͓͍ͯࡱ૾ΛߦͬͨɻFigure 6 ͕ͦͷ݁ՌͰ͋Γɺࢼྉ͸ϨʔβϙΠϯλ͓ΑͼίϯύΫτɾσδλϧΧϝϥͰ͋Δɻѱ৚͕݅ॏͳͬͨଌఆͰ͋Γɺࡱ૾࣌ؒ΋ 30෼ֻ͔͍ͬͯΔ͕ɺͦΕͰ΋ 60 keV ͷ୯৭ X ઢͷൃੜͱͦΕΛ༻͍ͨ X ઢ૾ͷऔಘʹ੒ޭͨ͜͠ͱ͸ɺμΠϠϞϯυ݁থͷ X ઢ‫ͯ͠ͱݯ‬ͷՄೳੑΛࣔ͢ͱ͍͏఺Ͱେ͖ͳҙ͕ٛ͋ͬͨͱ͍͑Δɻ

Figure 5: The result of the propagation-based phasecontrast imaging using the 40-keV PXR beam; upper: 0-m
propagation, lower: 4-m propagation. Each exposure timewas 30 min using an IP.
૾Λ‫ݟ‬Δͱɺ֦େ཰ʹؔͯ͠͸ଌఆͷ‫ز‬Կ৚݅ʹ੔߹͍ͯ͠Δ͕ɺࠨ൒෼ͷྖҬ͚ͩ 2 ॏʹμϒͬͨΑ͏ͳ‫ײ‬͡Ͱ૾ͷ඼࣭͕ѱԽ͍ͯ͠Δͷ͕Θ͔Δɻӈଆʹ͸ͦͷΑ͏ͳ‫ݱ‬৅͸‫ݟ‬ΒΕͳ͍ͷͰɺઢ‫ݯ‬αΠζʹ‫ى‬Ҽ͢Δ૾ͷϘέͰ͸ͳ͍ͱࢥΘΕΔɻλʔήοτ݁থͷଆ໘ͷ‫د‬༩ʹΑΓ૾͕ 2 ॏʹϒϨΔ‫ݱ‬৅͸γϦίϯ݁থͷ৔߹Ͱ΋‫͓ͯ͠ݧܦ‬Γɺ͜Ε΋λʔήοτ݁থ͋Δ͍͸ୈ 2݁থͷ‫ܗ‬ঢ়ʹ‫ى‬Ҽ͢Δ໰୊Ͱ͋ΔՄೳੑ͕ߴ͍ [8, 9] ɻ݁থʹ‫ى‬Ҽ͢Δ໰୊͸͋Δ΋ͷͷɺঢ়ଶͷྑ͍૾ͷӈଆͰൺ΂ΔͱɺX ઢͷ‫ٵ‬ऩ͕ऑ͍ϓϥενοΫͳͲͷܰ‫ݩ‬ૉͰߏ੒͞Ε͍ͯΔ෦෼ͷࢹೝੑ͕޲্͍ͯ͠Δͷ͕Θ͔Δɻ‫ٵ‬ऩͷ‫͍ڧ‬෦෼Ͱ͸໨ཱͬͨҧ͍͕ͳ͍

Figure 6: The results of X-ray imaging for a laser pointer(left) and a digital camera (right) using the 61-keV PXR
beam. Each exposure time was 30 min using an IP.

4.

݁থͷଛইͷ༷ࢠμΠϠϞϯυ୯݁থΛ PXR ઢ‫͢ݧࢼͯ͠ͱݯ‬Δ࣮‫ݧ‬Λऴ͑ͨ‫ޙ‬ɺμΠϠϞϯυ݁থΛऔΓग़ͯ͠ɺ௨ৗͷγϦίϯ୯݁থͷηοτʹ໭ͨ͠ɻऔΓग़͞ΕͨμΠϠϞϯυ݁থΛ֬ೝͨ͠ͱ͜Ζɺ൓ࣹ༻ୈ 2 ݁থʹ͸ಛʹ࢖༻લ͔ΒมΘͬͨͱ͜Ζ͸‫ݟ‬ΒΕͳ͔͕ͬͨɺλʔήοτ݁থ͸ࠇ͘ม৭͍ͯͨ͠ɻ࣮‫ޙݧ‬ͷλʔήοτ݁থͷࣸਅΛ Fig. 7 ʹ͕ࣔ͢ɺ༧૝௨Γແ਺ͷͻͼׂΕ͕ੜ͍ͯͨ͡ɻُ྾ͷํ޲͸ൺֱతଗ͓ͬͯΓɺ΍͸Γน։໘- 1224 -Proceedings of the 10th Annual Meeting of Particle Accelerator Society of Japan (August 3-5, 2013, Nagoya, Japan)ࢀߟจ‫ݙ‬

Figure 7: Photographs of the target crystal after the experiment, in which the crystal was irradiated with the 100-MeV
electron beam from the linac.
ʹԊׂͬͯΕ͍ͯΔͱࢥΘΕΔɻ·ͨɺFig. 7 ӈਤ͸݁থͷཪଆ (ిࢠϏʔϜ͕ൈ͚ͯग़ͯߦ͘ଆ) ͷࣸਅ͕ͩɺ‫ʹͱ͜ͳົح‬ɺද໘͕βϥβϥʹͳ͍ͬͯͨɻిࢠ͕ೖࣹ͢Δදଆʹ͸͜ͷ༷ͳมԽ͸‫ݟ‬ΒΕͣɺిࢠͷલํʹൃੜ͢Δ੍ಈ์ࣹͱؔ܎ͷ͋Δ‫ݱ‬৅͔΋͠Εͳ͍ɻࠓճ༻͍ͨμΠϠϞϯυ݁থ͸ɺ‫ͨݟ‬໨ʹ΋ԫ৭͘ෆ७෺ͱͯ͠஠ૉ͕ଟ͘‫·ؚ‬ΕΔ΋ͷͰ͋ͬͨͨΊɺిࢠͷরࣹʹΑͬͯΧϥʔηϯλʔ͕ੜ͡΍͘͢ɺ‫ٸ‬଎ʹࠇ৭Խ͕ਐΜͩ΋ͷͱࢥΘΕΔɻPXR ͷ‫ڍ‬ಈʹ͓͍ͯɺ઴ਐతʹ‫͕౓ڧ‬ऑ͘ͳΔৼ෣͍͸ಛʹ‫؍‬ଌ͞Ε͍ͯͳ͍ͷͰɺஅఆ͸Ͱ͖ͳ͍͕ɺిࢠরࣹʹΑͬͯࠇԖͳͲ΁݁থ͕ߏ଄มԽͯ͠͠·͏ͱ͍͏Α͏ͳӨ‫ڹ‬͸গͳ͍Α͏ʹࢥΘΕΔɻ໰୊͸΍͸Γ݁থͷͻͼׂΕͰ͋Δɻް͞ 1 mm ͱ͏͍͏λʔήοτͱͯ͠͸͔ͳΓް͍΋ͷΛ༻͍ɺ͔͠΋ಔ੡ͷϗϧμʔʹ͔ͳΓ͖ͭ͘‫ݻ‬ఆͨ͜͠ͱ͕ͻͼׂΕΛ༠ൃͨ͠Մೳੑ͕͋Δɻ·ͨऔΓग़͞ΕΔ PXRϏʔϜͷۭؒϓϩϑΝΠϧෆ‫ۉ‬Ұੑ΋ɺୈ 2 ݁থ΋‫ؚ‬Ίͯɺϗϧμʔ΁ͷ‫ݻ‬ఆͰੜͨ݁͡থͷ࿪Έ͕ͦͷҰҼͰ͔͋ͬͨ΋͠Εͳ͍ɻ݁থͷ‫ݻ‬ఆʹ͍ͭͯ͸ɺࠓ‫ݕޙ‬౼ͷ্ɺվળ͍ͯ͘͠ඞཁ͕͋Δɻ5.

[1] ૣ઒‫࢙ګ‬, Ճ଎‫ ث‬6 (2009) 166.
[2] Y. Takahashi, Y. Hayakawa, et al., X-Ray Spectrom. 41(2012) 210, doi: 10.1002/xrs.2403.
[3] M. Inagaki, Y. Hayakawa, et al., Jpn. J. Appl. Phys. 47(2008) 8081, doi: 10.1143/JJAP.47.8081.
[4] Y. Hayakawa, I. Sato, K. Hayakawa, T. Tanaka,Nucl. Instrum. and Meth. B 227 (2005) 32, doi:
10.1016/j.nimb.2004.06.028.
[5] Y. Hayakawa, K. Hayakawa, et al., Proceedings of the 6th Annual Meeting of Particle Accelerator Society of Japan, Tokai (2009) 748,
http://www.pasj.jp/web publish/pasj6/papers/toapa01.pdf[6] Yu. Adishchev, V. G. Baryshevsky, et al., Sov. Phys. JETP
Lett. 41 (1985) 361.
[7] Y. Hayakawa, K. Hayakawa, et al., Nucl. Instrum. and Meth.
B 266 (2008) 3758, doi: 10.1016/j.nimb.2008.02.042.
[8] Y. HAYAKAWA, K. HAYAKAWA, et al., IL NUOVO CIMENTO 34C (2011) 253, doi: 10.1393/ncc/i2011-10910-2.
[9] Y. Hayakawa, K. Hayakawa, et al., Proceedings of the 7th
Annual Meeting of Particle Accelerator Society of Japan,Himeji (2010) 788, http://www.pasj.jp/web publish/pasj7/
proceedings/P 5PM/P EH 5PM/THPS009.pdf

·ͱΊ

LEBRA-PXR ઢ‫ݯ‬ͷ 2 ݁থγεςϜΛ༻͍ɺࢢൢͰೖखՄೳͳμΠϠϞϯυ୯݁থΛ PXR ઢ‫͠ࢼͯ͠ͱݯ‬ͨɻ݁থͷ඼࣭΍αΠζʹؔͯ͠͸े෼ͱ͸͍͑ͳ͍
͕ɺ(400) ໘Λ༻͍Δ͜ͱʹΑΓɺैདྷͷγϦίϯ݁থͰ͸·ͩୡ੒͍ͯ͠ͳ͍ 34 keV Ҏ্ͷ PXR ͷൃੜΛ֬ೝ͠ɺͦΕΛ࢖ͬͯ X ઢ૾Λऔಘ͢Δ͜ͱ͕Ͱ͖ͨɻଌఆ্ͷ໰୊͸͕͋ͬͨɺ࠷ߴ X ઢΤωϧΪʔͱͯ͠61 keV Λୡ੒ͨ͠ɻ
ಘΒΕΔ PXR ϏʔϜͷ඼࣭ʹ͍ͭͯɺ఻ൖ‫ܕ‬Ґ૬ίϯτϥετΠϝʔδϯάʹΑͬͯ֬ೝͨ͠ͱ͜Ζɺ݁থͷঢ়ଶͷྑ͍ͱ͜ΖͰ͸ 40 keV ͰҐ૬ίϯτϥετͷޮՌ͕‫؍‬ଌͰ͖ͨɻ୯݁থΛ༻͍Ε͹ɺͨͱ͑ X ઢͷΤωϧΪʔ͕ߴ͘ͳͬͯ΋ɺγϦίϯ݁থͱಉ༷ʹۭؒίώʔϨϯτͳ X ઢϏʔϜ͕ಘΒΕΔ͜ͱ͕ɺPXR ͷຊ࣭తͳಛੑͱͯ͠Θ͔ͬͨɻ໰୊఺ͱͯ͠͸ɺిࢠϏʔϜরࣹʹΑͬͯλʔήοτ݁থʹಥൃతʹͻͼׂΕ͕ੜ͡Δ͜ͱ͕໌͔ʹͳͬͨɻ݁থͷଛইʹ͍ͭͯ͸ɺγϦίϯ݁থͱ͸܏޲͕େ͖͘ҟͳΔɻ݁থͷϗϧμʔ΁ͷ‫ݻ‬ఆ๏΋‫ݪ‬ҼͷҰͭͱߟ͑ΒΕɺࠓ‫ޙ‬վળ͍ͯ͘͠ඞཁ͕͋Δɻ

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