31P-Phosphorus
31P has 15 protons and 16 neutrons.
31P is a stable isotope.
The mass excess of 31P is -24440.54442 with an uncertainty of ±0.00075.
The mass was measured using a Penning Trap and the related equations include:
Influence Equations
51.8% 31P-28 SiH3 1
48.2% O2-31 PH 2
Reference
1. Redshaw, M., McDaniel, J., Shi, W., & Myers, E. G. (2006) Mass ratio of two ions in a Penning trap by alternating between the trap center
and a large cyclotron orbit. International Journal of Mass Spectrometry, 251(2-3 SPEC. ISS.)
https://doi.org/10.1016/j.ijms.2006.01.015
2. Matthew Redshaw, Joseph McDaniel, and Edmund G. Myers (2008), Dipole Moment of PH+ and the Atomic Masses of 28Si, 31P by Comparing Cyclotron Frequencies of Two Ions
Simultaneously Trapped in a Penning Trap Physical Review Letters 100(9)
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.100.093002