Helix SFT

High-resolution static vacuum mass spectrometer (SVMS) for precise noble gas isotopic analysis. Specially designed for the simultaneous analysis of helium isotopes, with advanced dual-focusing ion optics and a 35 cm, 120° magnetic sector analyzer.

• Status: Active
• Country: Germany
• Isotopic: Yes
• Analyte Type / Target Of Analysis: Noble gases
• Measurable Isotopes/Elements: Isotopes of noble gases
• Analyzer Type
  : Magnetic Sector MS
• Ion Source Type: Electron impact
• Signal Stability / Relative Standard Deviation
  : <0.2% drift per hour at 300 kcps; Drift to be less than the equivalent of +/- 50 ppm in mass over 30 minutes at mass 40
• Inlet Types: Dual inlet with getter pumps, pipettes, and cold traps
• High Resolution
  : Yes
• Mass Resolution/ Mass Resolving Power
  : Faraday detector: >400; Multiplier detector: >700
• Multicollector
  : Yes
• Collectors Qty
  : 5 Faraday detectors for high mass spur and SEV217 electron multiplier for low mass spur
• Sensitivity
  : Helium: >2×10−4 Amps/Torr; Argon: >1×10−3 Amps/Torr
• Abundance Sensitivity
  : <1 ppb for adjacent masses (3 contribution from 4) at a pressure of 1 x 10-7 mbar
• Dynamic Range
  : 1 cps to ~1.4 × 10⁶ cps
• Detection Limits
  : Sub-ppb levels for noble gases
• Detector Type
  : Faraday detectors and SEV217 discrete dynode electron multiplier
• Possible Amplifiers
  : 10¹⁰, 10¹¹, 10¹², and 10¹³ Ω resistors
• Background
  : Dark noise: <10 cpm (0.2 cpm typical)
• Geometry Type
  : Extended geometry with 120° deflection
• Focusing Type
  : Single focusing
• Magnetic Sector Radius/ Angle
  : 35 cm radius; 120° deflection
• Cooling System
  : Liquid nitrogen cooling for getter pumps; water cooling for turbo pumps
• Vacuum System
  : Ultra-high vacuum with 40 L/s ion pump, 70 L/s turbo molecular pump, and non-evaporable getter pump
• Gas Supply: High-purity noble gases (e.g., helium, neon, argon)