Table 2.

Isotope Fractionations in the Atmosphere of Mars Measured by the QMS and TLS Instruments of the SAM Suite on MSL

Isotopes	Mars Value	SAM Instrument
36Ar/38Ara	4.2 ± 0.1	QMS
40Ar/36Arb	1.9 (±0.3) ×103	QMS
14N/15Nc	173 ±9	QMS
δDd	4950 ±1080	TLS
δ13CVPDB	45 ±12‰	QMS
δ13CVPDB	46 ±4‰	TLS
δ18OSMOW	48 ±5‰	TLS

^aThis paper.

^bMahaffy et al. [2013].

^cWong et al. [2013].

^dWebster et al. [2013].

δ¹³C measured by the SAM Tunable Laser Spectrometer (TLS) and QMS in CO₂ is relative to Vienna Peedee belemnite standard, where ¹³C/¹²C = 1.1237 × 10⁻².

δ¹⁸O is relative to Standard Mean Ocean Water (SMOW) standard, where ¹⁸O/¹⁶O = 2.0052 × 10⁻³, and D/H is from H₂O (D/H_SMOW =1.5575 × 10⁻⁴).