Observation of Nuclear Transmutation Reactions induced by D 2

Transcription

1 Observation of Nuclear Transmutation Reactions induced by D 2 Gas Permeation through Pd Complexes Yasuhiro Iwamura 1, Takehiko Itoh 1, Mitsuru Sakano 1, Noriko Yamazaki 1, Shizuma Kuribayashi 1, Yasuko Terada 2 and Testuya Ishikawa 3 and Jirohta Kasagi 4 1 Advanced Technology Research Center, Mitsubishi Heavy Industries, Ltd. 2 Japan Synchrotron Radiation Research Institute 3 Coherent X-ray Optics Laboratory, SPring-8/RIKEN 4 Laboratory for Nuclear Science, Tohoku University ICCF-11, Marseilles, France, October31-November5, 2004

2 Contents 1. Introduction 2. Experimental method and Results so far 3. Experimental Results and Discussion 3-1 Transmutation of 137 Ba and 138 Ba into 149 Sm and 150 Sm : Mass distribution of Sm depending on the given mass distribution of Ba 3-2 Pr confirmation by XRF and experiments for in-situ measurement at SPring Consideration on the role of CaO layer 4. Concluding Remarks

3 Features of the Present Method D 2 gas permeation through the Pd complex Cs,Ba, etc. D 2 gas D Permeation Cross Section of Pd Complex Surface D Flux Vacuum CaO 2nm Pd 40nm Pd substrate Pd

4 Fabrication of Pd Complex Washing a Palladium Sample with Acetone 900 C 10H Annealing under Vacuum -7 Condition (< 10 Torr) Washing the Sample with Aqua Regia (100sec) 5 times Alternatingly Sputtering of CaO (20 ) and Pd (180 ) Ion Beam Sputtering of Pd only (400 ) Pd 400 Pd 0.1mm 25mm 25mm CaO/Pd 1000

5 Schematic View of the Experimental Apparatus X-ray Gun XPS Photoelectron Energy Analyzer Pd Complex Test Piece D Chamber A Evacuation Chamber B Ge Detector Q-Mass Evacuation D 2 Gas

6 Photograph of the Experimental Setup Photoelectron Energy Analyzer X-ray Gun D 2 Inlet Ge Detector Main Chamber

7 Decrease of Cs and Emergence of Pr Cs D Pd Pd CaO Number of atoms (/10 14 /cm 2 ) Cs 1st Pr 1st Cs 2nd Pr 2nd Time (h)

8 Identification of Pr by TOF-SIMS D 2 Gas Permeation Cs D Pd Pd CaO Pr Molecular Ions TOF-SIMS device (TRIFT TM ;ULVAC-PHI)

9 Decrease of Sr and Emergence of Mo Sr D Pd CaO Pd Number of atoms (/10 14 /cm 2 ) Sr 1st Mo 1st Sr 2nd Mo 2nd Sr 3rd Mo 3rd Time (h)

10 Relation of Isotopic Composition between Sr and Mo Isotope ratio (%) Given Sr Mass number (Natural abundance of Sr) Isotope ratio (%) Detected Mo Mass number 88 Mass N. +8 Sr Mo Atomic N. +4 Mass N Cs 59 Atomic N. +4 Pr

11 Recent Results Part 1 Transmutation of 138 Ba into 150 Sm and 137 Ba into 149 Sm

12 Transmutation of Ba into Sm; Natural Ba Natural Ba ( 138 Ba major) D Pd Pd CaO 150 Sm was detected after D permeation on the Pd complex

13 Schematic View of the Ex-situ Measurement Apparatus Pd Complex with an Element(Cs, Sr,Ba,etc) D2 Gas D 2 D B-A Gauge TMP Chamber A Chamber B B-A Gauge RP Ex-situ Measurement XPS, SIMS, ICP-MS, etc.

14 XPS Spectra for detected Sm Counts Sm 3d 5/2 Counts(Ba1st) Counts(Ba2nd) Sm 3d 3/ Binding Energy (ev)

15 Full Spectrum Natural Ba (138Ba major) D Pd Counts Pd C Sm 3d Sm 4d 5 0 Ba Pd CaO Binding Energy (ev)

16 Sm Natural Abundance 144 Sm 147 Sm 148 Sm 149 Sm 150 Sm 152 Sm 154 Sm 3.2% 15.1 % 11.3 % 13.8 % 7.5% 26.6 % 22.5 % Ratio to 152 Sm Sm Natural Abundance Mass Number

17 Ba Counts 10 4 Ratio to 152Sm SIMS Spectra for Given and Detected Elements Sm Natural Abundance Mass Number Sm 150 FG. BG % Pd40Ca 10 3 BaO 11.3% 7.8% 2.4% 6.6% Mass Number 155 BaO

18 Examination of Molecular Ions Pd Pd 40 Ca Ba Ba 16 O 102(1%) (0.1%) (11%) (0.1%) (22%) (2.4%) (27%) (6.6%) (26%) (7.8%) (12%) (71.7%) (11.3%) 154 No Molecular Ions for Pd(12%)Ca and 134 Ba(2.4%)O for mass150, however their effects should be lower than 106 Pd(27%)Ca and 138 Ba(71.7%)O

19 Transmutation of Natural Ba into Sm XPS analysis showed Sm signal. SIMS analysis showed the increase of mass 150. Natural Sm isotopic distribution did not match with SIMS mass data. These facts strongly suggests that 150 Sm exists on the Pd complex after D 2 gas permeation.

20 Transmutation of Ba into Sm; mass 137 Enriched Ba 137 Ba (Enriched Ba) D Pd Pd CaO 149 Sm may have been detected after D permeation on the Pd complex

21 137 Ba Ratio to 152Sm SIMS Spectra for #1Experiment Counts 100 Sm Natural Abundance Mass Number Pd40Ca 149 Sm FG. BG BaO Mass Number

22 Ba FG. BG. 100 Counts Ratio to 152Sm SIMS Spectra for #2 Experiment Sm Natural Abundance Mass Number 149 Pd40Ca Sm BaO Mass Number 155

23 Transmutation of 137 Ba into Sm SIMS analysis showed the increase of mass 149. Natural Sm isotopic distribution did not match with SIMS mass data. XPS analysis showed very weak Sm spectra. Now we are trying to obtain clear XPS signals. These facts suggests that 149 Sm exists on the Pd complex if we consider that Sm spectra were obtained by XPS using natural Ba.

24 Mass Correlation between Given and Detected Elements Ba d Ba Sm 500 M +12 Z Ba Given Element Sm 150 FG. BG. Given Element Detected Element 6d Ba Sm M +12 Z Detected Element Sm 149 FG. BG

25 The Aim of Ba Transmutation Experiments (3α ) Ba d 149 Sm 62 Experimental Results 149 Sm is a Mossbauer Isotope Excitation Energy: 22.5keV If we measure the Mossbauer effect of 149 Sm, we will obtain clear evidence of generation of 149 Sm. And the information on the ultra fine structure relating to the electronic state and phonon of the generated 149 Sm will be obtained.

26 Recent Results Part 2 Pr Confirmation by XRF and Experiments for in-situ Measurement at SPring-8

27 Identification of Pr by X-ray Fluorescence Detection of Pr using SOR X-ray at Spring-8, Harima, Japan (FG1, FG2: Signals from Samples after D2 Permeation BG: Signals from the sample before Permeation)

28 Experimental Set-up for in-situ Measurement located at SPring-8 Detector Evacuation Be Window Cl Filter Fluorescence X-ray SOR X-ray Evacuation Pd Complex with Cs D TMP Vacuum System DP D 2 Gas Inlet

29 Photograph of the Experimental Set-up BL-37XU Detector SOR X-ray Chamber

30 An Example of Pr Detection by the Experiments at SPring Cs- L α 1 Cs- L β Pr - L α 1 Co u n t s Cs- L β E n e r g y ( k e V) 6

31 Recent Results Part 3 Measurement and Experiments relating to the role of CaO

32 TEM Photograph of the Pd Complex Thin Pd Film : mm 25mm CaO and Pd Layers :1000 Bulk Pd : 0.1mm 400 Pd CaO Pd Substrate

33 Depth Profile of Cs and Pr by TOF-SIMS Counts(arv.unit) 8.0x10 Cs No D After D Cs 5 6.0x10 Pr 5 4.0x x10 Pr Sputtering time(sec)

34 Depth Profile of Cs and Pr by XPS(1) 10nm Atomic Ratio to Pd (%) B.G Cs F.G Cs F.G Pr Sputter Time (min)

35 D + Ion Bombardment Experiment Performed at Tohoku Univ. D+ Ion beam bombardment on metal target Experimental Apparatus d d d d Metal d d t d d P d d

36 Deuterium Density measured by D + Ion Bombardment Experiment Density of Pd complex(pd/cao) indicated one order larger than normal Pd

37 MgO cannot work instead of CaO Pd 40nm Cs MgO/Pd 100nm Pd 0.1mm 25mm 25mm No Pr; Two cases out of two experiments. ICP-MS measurements show no Pr(<0.01ng). D 2 gas Flow rate enough(2-3sccm) Pd 40nm Cs CaO/Pd 100nm Pd 0.1mm 25mm 25mm Almost every time Pr were detected. More than 60 cases.

38 Consideration on the Role of CaO Increase of Deuterium Density? Modify the Electronic State of Surface Pd? Depth Profile Measurement of D By a Resonance Nuclear Reaction Li( 1d, γ ) 9 4 Be

39 Concluding Remarks 1. Transmutations of Ba into Sm were observed both when natural Ba was applied to the Pd complex samples, and when mass-137-enriched Ba (monoisotopic Ba) was applied. The mass distribution of Sm that we obtained depended on the starting isotopic distribution of Ba One of our experimental apparatus was carried to SPring-8 to perform an in-situ measurement. We obtained some Pr signals by the X-ray Fluorescence method. According to a D + ion beam bombardment experiment performed at Tohoku University, the deuterium density of our Pd complex indicated one order larger than normal Pd.