Mass spectrum equipment of accelerator, and method for measuring mass spectrum 14C of accelerator

Abstract

A mass spectrum unit of accelerator consists of ion source, beam buncher, RFQ accelerator, electronic stripper, high energy analyzing system and detector. It is featured as connecting said unit and system in sequence; accelerating 14C, 12 C and 13C ion separately to be at certain energy for carrying out electronic lift off by R is not equal toQ accelerator in order to eliminate disturbance of molecular ion.

Description

technical field [0001] The invention belongs to the technical field of accelerator mass spectrometry, in particular to an accelerator mass spectrometry device and an accelerator mass spectrometer based on a low energy dispersion RFQ accelerator 14 C measurement method. Background technique [0002] Accelerator mass spectrometry (AMS), as an analytical technique with ultra-high sensitivity, has been widely used in the fields of earth science, archaeology, life science, environmental science, astrophysics and material science. The main measurements of the AMS device 14 The ratio of C and other radionuclides to their stable isotopes can be used for dating or tracing research. It uses an accelerator to accelerate the nuclide ions to be tested to a higher energy, which can effectively suppress molecular ions and isobaric interference. achieve ultra-high sensitivity. AMS performance is mainly measurement accuracy, sensitivity and measurement efficiency. [0003] A general AMS ...

AI Technical Summary

Problems solved by technology

Both types of accelerators use the high-voltage electric field generated between the high-voltage electrode and the ground potential to accelerate ions. The high-voltage electrode and the accelerating tube need to be placed in a steel cylinder filled with high-voltage SF 6 Gas for insulation, apparently using SF 6 Gas is not good for environmental protection

In order to ensure the insulation effect, more complex devices such as gas circulation drying treatment are required

In order to ensure the measurement accuracy, different isotope ions need to be accelerated through the accelerator, but the beam loading capacity of this type of accelerator is low, and a relatively complex alternate injection system is required, so that the stable isotope with high flow intensity can only be injected into the accelerator in a short time

Some people also use the method of simultaneous implantation, but the implantation system is more complicated. It is necessary to separate the different isotope ions first, attenuate the stable isotope ion beam with a higher current intensity, and then inject the different isotope ions into the accelerator.

The measurement background of this simultaneous injection method is relatively high, and the corresponding high-energy analysis system is relatively complicated.

[0004] Recently, a Single Stage AMS (SSAMS) device has appeared. This device uses a 300kV single-stage electrostatic acceleration tube and does not require a steel cylinder. However, some devices are inevitably at high potentials, which is inconvenient to operate and has certain limitations. , and the measurement sensitivity is affected to a certain extent due to the low energy

[0005] There is also a small cyclotron that is also used in AMS. The AMS based on this kind of accelerator has low measurement accuracy and measurement efficiency due to the restriction of transmission efficiency.

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