Motivation of experiment, preliminary measurements. Overview of MCF prospects and technology applications

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2 I History of muon catalyzed fusion (MCF) MCF measurements in Dubna Method of MCF study Experiment in t+t system II DD-gamma experiment Motivation of experiment, preliminary measurements Background discrimination measures Monte-Carlo simulations Determination of registration efficiency Expected results III Overview of MCF prospects and technology applications

3 MCF cycling diagram Muon lifetime is 2.2 microsecond Muon mass is 207 Electron mass Average cycle number Obtained obstacles: impurity, sticking to He 120

4 PREDICTION NON-RESONANT MECHANISM CALCULATIONS

5 Semen Gershtein

6 DISCOVERY

7 Venedikt Dzhelepov

11 EXPLANATION OF RESONANT MECHANISM OF MESOMOLECULE FORMATION

13 PREDICTIONS FOR D-T SYSTEM SOLUTION OF 3-BODY SYSTEM WITH ELECTRO-MAGNETIC INTERACTION Leonid Ponomarev (at the right)

14 D+T

15 EXPERIMENTAL CONFIRMATION

19 PHYSICS SCOPE

20 MCF Experiments in Dubna

21 Valentin Zinov

22 TRITON installation

23 D+D liquid and solid

26 D+T liquid and gas

30 HIGH PRESSURE TARGET 800 bar, 800 K

32 100 different points of temperature, density, and tritium content had been measured

35 Sticking probability in DT cycle was found as low as 0.5%

36 Epithermal effects in H-D-T system

37 Project MU-CATALYSIS JINR Project statistics in : Collaboration with other institutes: TUDelft (Delft, Netherlands), INP (Krakow, Poland), MUCATEX (Moscow), VNIIEF (Sarov), ITEP (Moscow), SSC KI (Moscow) -The number of publications in refereed journals: 8 -Participation in the conferences: EXA-02 (2002, Vienna, Austria), MCF-07 (2007, Dubna, Russia) MuCF-01 (2001, Shimoda, Japan), Yadro-2006 (2006, Sarov, Russia) -Awards in scientific conquests: First prize JINR 2002, First prize JINR Sources of extra budget financing: Contracts with Agency Rosatom ; ; Grants RFBR ; ; ; ; , Grant INTAS

38 T+T liquid In press

40 Liquid tritium target

47 75% 20%

50 Project MU-CATALYSIS JINR Project continuation in : Investigation of the nuclear fusion reactions in muonic deuterium and tritium Goal of the Project is obtaining of new experimental data on Muon Catalyzed Fusion (MCF) in the areas, where they are absent or ambiguous. The experiments will be conducted in JINR (Dubna, Russia) at the installation TRITON. The Project is divided into separate tasks. In the current task by means of muon catalysis we address phenomena in dd fusion, which have not been previously investigated and are at the frontier of nuclear few-body physics. For this purpose we propose an experiment to study the muon-catalyzed radiative deuteron capture from muonic deuterium molecules ddμ 4Heμ + γ +23.8MeV. We will measure the relative yield of this rare reaction from the p-wave state of deuterons in a muonic deuterium molecule with sensitivity of 10-7 with respect to main fusion channels. (Task duration according INTAS grant)

51 H. Weller s device (TUNL, 1981)

52 UNIVERSE EARLY DAYS D+D reaction gives Helium Beam-target experiment gives a result with 50% p-wave channel!

53 The d(d,g)4he reaction has specific features because identical bosons are involved in the entrance channel. This requires that the sum of the relative orbital angular momentum and the total spin in the entrance channels be an even number (L+S must be even). For E1 radiation, usually dominating in capture reactions at low energies, this requirement is met only by (L=1, S=1) or by the 3 P 1 (1 - ) initial state. E1 transitions in self-conjugate nuclei are known to be prohibited in the lowest order by the isospin selection rule ΔT=±1. The E1 transition to the 4He ground state (S=0 or S=2) should be additionally suppressed since it involves a spin-flip ΔS =1. Cross section angular distributions σ(θ), vector Ay and tensor Ayy analysing powers measured with a polarized deuteron beam of energy Edlab= 60 kev revealed a 50% p-wave strength (E1 and M2) in the 2 H(d,γ) 4He reaction [Weller et al.]. (In the case of M2 radiation 3 P 2 (2 - ) capture is possible.) This non-e2 radiation was then validated and a new S-factor extrapolation was obtained (solid line in Figure 3) that reduced the previously accepted value by ~25%. To observe the p-wave effects in reaction (1) at almost zero energies we exploit the ddμ molecule resonant formation in the J=1 state at temperatures T>150 K. This phenomenon was discovered in JINR and later observed and studied in many laboratories. The Weller results being considered the expected level of effect would be 10-6.

54 DD-gamma Data digging

The equipment was developed for the study of probability of strongly suppressed process of deuteron radiative capture from the state of deuterium muonic molecule at room temperature, the preliminary

55 The equipment was developed for the study of probability of strongly suppressed process of deuteron radiative capture from the state of deuterium muonic molecule at room temperature, the preliminary measurements have been made - less than 10-5 per one muonic molecule formed. Physics of Atomic Nuclei, Vol. 65, No. 10 (2002)1178 Proposed experimental setup: PS plastic scintillator, BGO - crystal New method for high-background measurements in development: Spike PS, further exponent - BGO

57 Gamma detector

60 Two modifications of gamma-detectors are created based on the crystals BGO (Ø127х60мм). First working modification is combined BGO+plastic (sandwich-type), the second modification is a test one without plastic (bare- BGO). The beginning of the development of the third modification starts, which will be the variant of BGO+plastic viewed by a single photo-multiplier. This third concurs against the first modification to be applied in the main measurement.

61 The experimental measurements of bare BGO detector modification (background conditions including cosmic radiation) in the experimental area of JINR Phasotron, the exposure was taken during 4 hours

62 Influence of 5cm Pb shielding

63 The experimental spectrum Со-60, obtained with the gamma-detector. It is seen from the figure that gamma-lines 1.17, 1.33 MeV are at the edge of resolution Two-dimension plot in the detector s energy space of signal-shape branches: only BGO corresponds to long type of signal, only plastic corresponds to short signal type in (At axis X is depicted integrated over 30ns the short component of a response signal, at axis Y the total length integrated response)

64 Yu. Vinogradov et al. (VNIIEF, 2006) internal report The experimental spectrum of gamma-quanta obtained at EGP-10 (gammaspikes are having complicated structure) (At X-axis is Energy in kev, At Y-axis is response in pulses/kev )

66 Monte-carlo calculations

67 On the figure is shown a frame with 10 gamma generated. Green tracks present path of gamma particles.

68 23 MeV gamma registration

69 23 MeV gamma bremstrughlung

70 23 MeV gamma energy spectrum and bremstrughlung Position uniformity for 1PMT and 4PMT versions

71 23 MeV gamma line including selection criteria For 1PMT And 4PMT versions

72 GEANT4 implementation Energy losses, appearing in the course of moving the particles in the detector, are written down in the manner of Ntuple s records. They are subsequently used by program for building analyzing histograms. Physics list subprogram with electromagnetic and optical physics facilities has special importance, describing behavior of the particles in various situations. In particular in case of the different conditions appearing on the optical surfaces between different optical media (BGO crystals and plastic scintillator, teflon, PMTs). The order of the value in the number of photons amounts to photons born in one experimental event (registration of single 23.8 MeV gamma). The GEANT4 program was written with the implementation of optical processes (scintillation, rayleighscattering, absorption, boundary processes).

73 At the beginning of modeling program is generated the unified distribution in the target and having unified distribution in the direction of moving. All the secondary particles, born in the course of gamma moving, are traced by program in the course of their tracking in the detectors. For writing Ntuples in forms of ROOT files were used OpenScientist AIDA implementation ( The GEANT4 simulated efficiency of the gamma detector in the energy range MeV in the geometry of the installation considered amounts to (9.5% of gammaconversion inside BGO) This result is confirmed by the energy deposited inside BGO crystal as well as by photons born due to gammaconversion inside BGO.

77 Run duration: 100 h muon stop rate: 1000 s -1 number of muon stops: 3*10 8 cycles per muon stop: 2.7 cycles occurred: 10 9 electron registration eff.: 0.5 cycles registered: 5*10 8 gamma registration eff.: 0. 1 gamma per cycle (theory): 10-6 number of gamma expected: 50 events background level expected: events

78 STATUS of the experiment The BGO-detectors for experimental study of d+d MCF radiative capture reaction are manufactured and their characteristics are measured with gamma-sources and with the use of Sarov s EGP-10 facility. The results are well described with modeling Monte Carlo program using GEANT-4. The background measurements with BGO-detectors are performed at different composition of background rejection system and the optimal active and passive shielding is chosen. The high pressure deuterium target and the gas handling system is created in Sarov. The electronics of the experiment is ready and trigger conditions are chosen. The support system for passive shielding will be ready within 2 month. So the installation will be ready to begin measurements in autumn The data handling finished for t+t MCF experiment and the paper is ready for publication. The analysis of the experimental data aimed at revealing the mechanism of the reaction is in progress.

79 THE FUTURE PLAN The next task is to determine parameters of MCF d+t reaction at high temperatures, where theory predicts the high intensity of the process and experimental data are absent. This task consists in the measurements of MCF parameters in D/T and H/D/T mixtures at high temperatures K and pressures (~1kbar). Domestic experiment. STATUS: Sarov party have the idea of how to produce the tritium target Task duration beyond 2009

81 THE FUTURE PLAN - 2 Prolongation of the dd-gamma experiment in a meson facility STATUS: idea of how to improve the dd-gamma measurement accuracy Task duration beyond 2009 Measurement of MCF in deuterium in a high magnetic field in a meson facility Toward creation of a neutron source of 14 MeV neutrons STATUS: idea of how to measure the influence of a high magnetic field on the sticking coefficient in deuterium Task duration beyond 2009

83 MCF applications

86 Nuclear power engineering effort military A-bomb H-bomb N-bomb civil Fission power plant Fusion power plant MCF power plant

87 N (slow ) U = 200 MeV 50kt 150 years deposit Fission power plant N (fast) U = 239 Pu + γ Fusion power plant Electro-nucl. breeder MCF power plant 1 thermal n needs 2 fast n breeders Will be able Heating water 1/2 effective fast n (breeder)

88 MCF power plant concept D + T = 4 He (3.5 MeV) + n (14.1 MeV) n (14.1 MeV) U = 4n 1 neutron power gain MeV neutron produces 3n U = 239 Pu n + 6 Li = 4 He + T 460 MeV fission fuel ( 239 Pu) Neutron flux = breeding = fission fuel + fusion fuel + Neutron flux = incineration of nuclear waste

89 Total power gain (for 239 Pu fuel) MCF breeder power plant 4 Fast neutron breeder power plant 5 MCF power plant utilizes not only 238 U but also 6 Li So MCF power plant fuel is 85% 6 Li + 15% 238 U

μcf 07 SUMMARY TALK 73 participants 54 talks 27 laboratories 14 states Leonid I. Ponomarev RRC Kurchatov Institute and MUCATEX

μcf 07 SUMMARY TALK 73 participants 54 talks 27 laboratories 14 states Leonid I. Ponomarev RRC Kurchatov Institute and MUCATEX μcf 07 SUMMARY TALK Leonid I. Ponomarev RRC Kurchatov Institute and MUCATEX 73 participants 54 talks 27 laboratories 14 states 1 1937 - muon discovery 1947 - prediction of μ catalysis 1957 - observation