Van Allen Probe B Spinfit DC Electric Field estimates level-2 in M-GSE coordinates

This data set contains spinfit DC Electric Field estimates in M-GSE coordinates that are measured by the Electric Field and Waves Suite (EFW) onboard Van Allen Probe A. One 2D vector estimate of the E-field is computed at a cadence of once per spin period (typically 10.7 to 11.1 s) using the survey E-field data product - the potential difference between EFW sensors V1 and V2 (E12) sampled at a nominal rate of 32 samp/s with a resolution of 16 bits. The X-component of the E-field estimate, corresponding to the axial component in the spacecraft coordinate system, is set to zero in this data product. See the EFW-FAQ (http://rbsp.space.umn.edu/efw_faq.html) for a discussion of this convention for this data product. The VxB electric field in the spacecraft frame due to orbital motion of the spacecraft around the Earth as computed from the spacecraft orbital velocity and measured B-field in the spacraft frame has been subtracted from the measured electric field, and so the data product is in the quasi-inertial frame equivalent to GSE (i.e. it is NOT in the corotation frame of the Earth!). Each spin fit is time-tagged with the time corresponding to the middle of the spin of data that went into the spin fit algorithm; in other words, if a given spin covers the interval (t1, t2), then the spin fit E-field estimate associated with that spin is given the time tag 0.5*(t1 + t2). The root mean square residual between the data included in the fit and the resulting best-fit model, sigma, and the final number of points included in the spin fit, npts, are also provided at spin-period cadence. The nominal dynamic range of the E-field estimate is +/- 1 V/m in any component.