Note: A portable pulsed neutron source based on the smallest sealed-type plasma focus device

Abstract

Development and operation of a portable and compact pulsed neutron source based on sealed-type plasma focus (PF) device are reported. The unit is the smallest sealed-type neutron producing PF device. The effective volume of the PF unit is 33 cm(3) only. A compact size single capacitor (4 μF) is used as the energy driver. A battery based power supply unit is used for charging the capacitor and triggering the spark gap. The PF unit is operated at 10 kV (200 J) and at a deuterium gas filling pressure of 8 mb. The device is operated over a time span of 200 days and the neutron emissions have been observed for 200 shots without changing the gas in between the shots. The maximum yield of this device is 7.8 × 10(4) neutrons/pulse. Beyond 200 shots the yield is below the threshold (1050 neutrons/pulse) of our (3)He detector. The neutron energy is evaluated using time of flight technique and the value is (2.49 ± 0.27) MeV. The measured neutron pulse width is (24 ± 5) ns. Multishot and long duration operations envisage the potentiality of such portable device for repetitive mode of operation.

High yield (⩾108/pulse) DD neutron generator based on a compact, transportable and low energy plasma focus device

“…The outer diameter and the effective length (exposed to plasma) of the quartz sleeve were chosen to be 25 mm and 46 mm, respectively. The insulator dimensions were decided on based on the experience gained from developing other PF devices here [19][20][21][22][23][24]32] and comparison with other devices operating worldwide in the same energy range.…”

“…In view of its wide-ranging applications, the PF device has been extensively developed and characterized in different laboratories across the world at wide operating energy ranging from 0.1 J to MJ [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] since its inception in the early 1960s independently by J W Mather [13] and N V Filippov [14]. Even after more than six decades of intensive research and development, it is still being developed worldwide for various applications as mentioned above.…”

Development of a portable pulsed fast ⩾106 neutron generator based on a flexible miniature plasma focus tube

“…Numerous portable pulsed neutron generators of neutron yield ∼10 6 neutrons/pulse or less based on the plasma focus device have been developed worldwide in different laboratories [25][26][27][28][29][30][31][32]. For example, Silva et al [25] reported a maximum neutron yield of (1.06 ± 0.13) × 10 6 neutrons/shot at 9 mbar filling pressure of D 2 gas in a very small and fast plasma focus device operated at ∼400 J.…”

Surface modifications of fusion reactor relevant materials on exposure to fusion grade plasma in plasma focus device

“…It has been extensively operated and characterized in various laboratories [1][2][3][4][5][6][7][8][9][10] across the world. The PF devices have been operated at capacitor bank (CB) energies ranging from 10s of Joule to MegaJoule with different gases (H 2 , D 2 , N 2 , Ar, CH 4 , etc.).…”