Thermal Ionization Mass Spectrometer (TIMS) is an analytical tool for accurate isotope ratio measurement of elements. Owing to its high sensitivity, selectivity and precision it finds extensive applications in the field of nuclear industries and geochronology. It consists of a thermal ionization source for ionization of the sample, sector electro-magnet for separation of ions and faraday collectors for the measurement of ion current. The instrument control and analysis is through a PC based interface.


                                                       SALIENT FEATURES

    Sample quantity of only a few micrograms (due to high sensitivity)
    Highly precise isotope ratio measurement
    Sufficiently high resolution and mass range(m/z 450)
    High throughput with un-attended pre-heating facility for samples
    PC interface for instrument control, and data analysis
    Ultra high vacuum environment using Turbo-molecular pump and sputter ion pump
APPLICATIONS

    Isotope analysis of reactor fuel, spent fuel and reprocessed fuel in nuclear industry
    Exploration studies in Geo-chronology
    Concentration measurements using isotope dilution
    Isotope signature studies of soil samples in earth science

INTRODUCTION
Thermal Ionization Mass Spectrometer (TIMS) is an analytical tool for accurate isotopic ratio measurement of elements. Owing to its sensitivity, selectivity and precision it finds extensive applications in the field of nuclear industries and geochronology. It consists of a thermal ionization source for ionization of the sample, sector magnet for separation of ions and Faraday collectors for the measurement of ion current. The instrument control and analysis is through a PC based interface.


SALIENT FEATURES
•    Sample quantity of only a few micrograms needed due to high sensitivity.
•    Highly precise isotopic ratio measurement
•    Enough resolution and mass range for all elements with masses up to 450 amu
•    High throughput due to un-attended pre-heating of the samples
•    PC interface for instrument control and sample analysis
•    Ultra high vacuum generated by Turbo-molecular pump and sputter ion pump

APPLICATIONS
•    For isotopic analysis of reactor fuel, spent fuel and reprocessed fuel in nuclear industry
•    Exploration studies in Geo-chronology
•    Concentration measurements using isotopic dilution
•    For isotopic signature studies of soil samples in earth science

SPECIFICATIONS
Resolution            : 400 (10% valley)
Mass Range            : up to 450 amu
Sensitivity            : 1 ion for 600 atoms of Uranium
Precision            : 0.1% for Natural Uranium
Abundance sensitivity     : 30 ppm (for U-238 at mass 237)

ION SOURCE
Ionization technique        :  Thermal ionization
Filament Assembly type    :  Triple Filament assembly
Filament type                          :  Rhenium ribbon (size 0.75 mm wide, 0.03 mm thick)
Turret    capacity        :  12 filament assemblies
Sample quantity        :  2-3 microgram of Uranium
Sample form                     : Acidic solution loaded on side filaments and dried in atmosphere by electrical heating
Acceleration Voltage    :  up to 10 kV (routine operation at 7 kV)
ANALYSER
Type        : Magnetic Sector
Sector Radius    : 30 cm
Sector Angle    : 90°
Geometry type    : Stigmatic (with entry and exit angles: 26.5°)

COLLECTOR SYSTEM
Collector Type    : Faraday collector
Number of collectors    : Six
Collector locations    : Fixed
Dispersion adjustability    : Variable dispersion zoom optics

VACUUM SYSTEM
Vacuum          : 1 x 10(-7) torr in ion source, 3.0 x 10(-8) torr
                                                      in collector side
Vacuum Pump (Ion source)         : Turbo molecular Pump (TMP) with 600 L/s       
                                                      pumping speed
Vacuum Pump (TMP backing)   : Rotary pump with capacity 10 m3/h
Vacuum Pump before analyser  : Sputter ion pump with 35 L/s capacity
Vacuum Pump after analyser         : Sputter ion pump with 70 L/s capacity
Cold thimble              : Available on the ion source chamber

INFRASTRUCTURE REQUIRED
Mechanical fabrication workshop with lathe machine, Milling machine, TIG welding, Insulation and HV tester, access to leak testing facility.

Electronic Lab Facility for Testing Purpose
PCB assembly & instrument rack wiring facility.
Measuring instruments like 6 and 1/2 digit precision digital multimeter & Oscilloscope, Function Generator

Space
Instrument foot print    :     2 sq. Meter
Total working space    :     50 sq. meter

RAW MATERIAL
Most of the components are available within the country and some components (Filament ribbons, vacuum pumps etc.) need to be imported through local agents.

MANPOWER
One graduate in science, one electronics engineer, two trained technicians will be required for manufacture/production of this instrument.




For details contact:

Head, Technology Transfer & Collaboration Division,
Bhabha Atomic Research Centre,
Trombay, Mumbai  400 085.
Fax: 091-022-5505151
e-mail: headttcd@barc.gov.in