Improved Faraday collector for magnetic sector mass spectrometers

Design and development of a compact thermal ionization mass spectrometer for isotope ratio measurement of uranium

“…Thermal ionization mass spectrometry (TIMS) is a widely used analytical tool for the determination of precise isotope ratios of elements of interest in geochronology, environment and nuclear applications 1–5 . The design enhancements of the subsystems, namely ion source, magnetic analyser and collector system, and their benefits were elucidated in our earlier publications 6–9 . The overall size of the TI mass spectrometer is defined by the sector radius ( r ), deflection angle (Φ), entry ( ɛ i ) and exit angles ( ɛ o ), which are determined by the required resolution and dispersion for the collection of nearest isotopes on adjacent collectors for the given analyte element.…”

“…This development involves ab initio calculations for the ion‐optical elements, the validation through simulation studies on the sector magnet geometry and VDZO specific to a 20 cm magnetic sector using SIMION 7.0 15 software and subsequent experimental verification. This paper discusses the results on various performance parameters such as resolution, maximum mass achievable, precision, sensitivity and abundance sensitivity using the uranium standard and compares them with the results from a 30 cm TI mass spectrometer developed by us 6‐9 . The TI mass spectrometer with a 20 cm sector radius (current development) and the one with a 30 cm sector radius will be referred to as the compact TI mass spectrometer and the conventional TI mass spectrometer, respectively, throughout this paper.…”

“…[1][2][3][4][5] The design enhancements of the subsystems, namely ion source, magnetic analyser and collector system, and their benefits were elucidated in our earlier publications. [6][7][8][9] The overall size of the TI mass spectrometer is defined by the sector radius (r), deflection angle (Φ), entry (ϵ i ) and exit angles (ϵ o ), which are determined by the required resolution and dispersion for the collection of nearest isotopes on adjacent collectors for the given analyte element. The lower limit on sector radius is imposed mainly by the dispersion.…”

“…The commercial (Thermo Fisher, Waltham, MA, USA, and Isotopx Ltd, Middlewich, UK) or in-house built models [7][8][9][10][11] of TIMS instruments available to date have standardized the geometries on either 27 or 30 cm radius magnetic sectors to facilitate larger dispersion accommodating the physical size (typically 2 mm) of the collector cups for closely spaced isotopes. The larger sector radius becomes even more important for some of the commercial models employing a complex collector system [12][13][14] with a greater number (e.g.…”

“…This paper discusses the results on various performance parameters such as resolution, maximum mass achievable, precision, sensitivity and abundance sensitivity using the uranium standard and compares them with the results from a 30 cm TI mass spectrometer developed by us. [6][7][8][9] The TI mass spectrometer with a 20 cm sector radius (current development) and the one with a 30 cm sector radius will be referred to as the compact TI mass spectrometer and the conventional TI mass spectrometer, respectively, throughout this paper.…”