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Stable Isotope Laboratory

Stanford University
Geological and Environmental Sciences, Bldg. 320
Stanford, CA 94305-2115
Tel: 650-723-0817, Fax:650-725-2199



Finnigan MAT Delta plus Isotope Ratio Mass Spectrometer (IRMS):

 Description: The Finnigan MAT Delta plus IRMS has a continuous flow (Conflo IITM) interface connecting an elemental analyzer, three faraday collectors, with a Pentium PC running ISODATTM software.

 Power requirements = 230V (-10%, + 6%), 16A three phase, 50/60Hz. Max permissible voltage between ground and neutral lines < 400mV.

 Compressed air supply = 50 to 75psig. (350 to 500Kpa).

 Reference gases for N2 and CO2.

 Environment = Heat output 2.5kW during normal operation; 4.5kW during system bake-out.

 Ambient temperature range = 64 to 82°F (18-28°C).

 Relative humidity range = 20 to 70%.

 Dimensions = 33.5in H x 34.3in W x 36.6in D (85cm H x 87cm W x 93cm D).

 Weight = 550lbs (250kg).

Finnigan MAT Delta plus IRMS specs:

 Sensitivity = 1500 molecules CO2/mass 44 ion

 Internal precision 2s 13C @ 3 µl CF = 0.020ppt; @ 10 µl CF = 0.006ppt.

 Internal precision 2s 18O @ 5 µl CF = 0.04ppt; @ 10 µl CF = 0.012ppt.

 Internal precision 2s 15N @ 10 µl CF = 0.05ppt; @ 20 µl CF = 0.010ppt.

 Internal precision 2s 32S @ 10 µl CF = 0.010ppt.

 External precision 1s 13C @ 3 µl CF = 0.05ppt; @ 10 µl CF = 0.02ppt.

 External precision 1s 18O @ 5 µl CF = 0.10ppt; @ 10 µl CF 0.04ppt.

 External precision 1s 15N @ 10 µl CF = 0.15ppt; @ 20 µl CF = 0.03ppt

 External precision 1s 32S @ 10 µl CF = 0.02ppt.

 Linearity 0.02 ppt/nA ion current mass 44


A Carlo-Erba Na1500 Series II elemental analyzer is connected to the Finnigan Delta plus IRMS. For more information refer to the Carlo-Erba Na1500 Series II specification sheet.


Department of Geological and Environmental Sciences / Stanford University
Last modified on 5/11/05 by David Mucciarone (e-mail address - dam@pangea.stanford.edu).