Supply, Installation and Commissioning of Accelerator Mass Spectrometry (AMS)

A-SAMPLE PREPARATION SYSTEM Graphitization System The automated graphitization equipment should be provided to graphitize the liquid and solid samples in a fully automated way. It should include all essential components/accessories, elemental analyzer, graphitization reactor, oven, cooler, transducer, Sample reactor/holder, Inlet port and traps etc with following specifications- a) Capable of processing samples corresponding to a total combustion mass up to 150 mg or more. b) Capable of producing graphite having carbon in the range of 200 μg C to 1000 μg C, or better. c) Suitable for samples having carbon concentrations ranging from 5% to 100%, or better. d) Process blank over AMS: should be less than 0.003 Fm. e) Sample cross-talk: ≤ 1‰ for a 1000 μg carbon sample. f) System shall provide processing capability for a minimum of seven graphitization reactors, higher capacities may be offered.

B-AMS SYSTEM AMS System should include four major parts i.e. Ion Source/ Injector System, Low energy magnet/ spectrometer/ injector & magnet, Accelerator and High Energy Mass Spectrometer/ High Energy Magnet. The summarised specification are as follows: 1) Ion Source/ Injector System Type of Ion Source: Multiple cathode negative ion source: a) Injection voltage / energy: maximum 100 kV, b) Ion current (12C- low energy): maximum 100 µA, c) Number of samples: Minimum 40 samples (continuous measurement) 2) Low Energy Magnet/ Spectrometer/ Injector & Magnet a) Magnet type: Electromagnet/permanent magnet, b) Types of isotopes measured: 12C/ 13C/ 14C, c) Type of Faraday cups: Offset/others, d) Necessary vacuum system/pump with base pressure less than or equal to 5 x 10-7 torr. 3) Accelerator a) Type: single ended accelerator or tandem, b) Terminal voltage: range 50-300 kV, c) Voltage generation: Solid state power supply d) Terminal gas stripper, if any: Nitrogen/ Argon /Helium. 4) High Energy Mass Spectrometer / High Energy Magnet a) Magnet type: Electromagnet/permanent magnet, b) Faraday cups for 12C & 13C , c) Electric field: Electrostatic analyser (ESA), d) 12C Beam transmission: 40% or more, e) 14C detection system: I. Detector System- solid state detector or gas state detector a) Precision for 1 mg graphite with a modern reference material, II. 14C/12C: 0.2% or less, III. 13C/12C: 0.2% or less, IV. Background for 14C/ 12C of a processed and unprocessed blank sample: 2×10-15 or better.

C- OPERATION, SOFTWARE, COMPUTER AND DATA MANAGEMENT 1.In view of the presentation made to the committee, the committee recommended to go for the option of low voltage accelerator upto 300 kV as it suits the proposed application and there will be no compromise to generate quality data. The focus of machine analysis should be measurement of the carbon isotope (C-isotope) as per requirement of CAP. 2.All the features of the data station such as operating system, controller software, hard disk storage capacity, memory, printer(s) etc. should be provided. 3.The system should be fully automated for control and sample measurements and party should provide data base server to systematically manage the result of samples. 4.Automation system to enable personnel for fast work and efficient time utilization by intervening only at the sample loading and analysis stages. 5.Operation should be user-friendly, easy to use and prevent mistake with intuitive structure. 6.The original licensed software(s) with respect to operating system, control system, processing software, data management system, reporting AMS results (including age calculation) and other accessories should be provided along with the AMS system, and all should have the validity for the entire life cycle of the AMS system. 7.Upgraded software compatible with original licensed software provided with the AMS system will be provided free of cost by the bidder for the entire life cycle of the AMS system. 8.Test samples and standards for performance measurement should be provided by the supplier.