ACE/SEPICA Release Notes:
Note: add newer notes to the top of this file

02 Feb 2006 Add Nitrogen data

24 March 2001 Version 6
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< ver4

	Level2 files produced prior to version 4 used SEPICA's matrix and
sectored rates alone.  The problem with this, is that it cannot take into
account results of trails moving out of the box definitions in the dpu.

ver4

	The first version of the level2 files produced using the more
advances pha/basic rate normalization method.  The software producing
these files could not reliably track large scale pressure changes, and it
was possible for trail contamination to occur.

ver5

	Version 5 takes into account changes in pressure, and reliably
keeps the proper trails in the proper boxes, but a bug introduced caused
boxes He5, He6, He7, and He8 to give improper flux readings.

ver6

	Virtually identical to ver5 except for the removal of the
aforementioned bug.



5 October 2000 Version 4
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He rates:

Two He rates have special significance because they include the ions from
the internal Am241 calibration source in SEPICA. They are: He4cal and 
He Cal Alpha check (HeCAck). The difference between them is that 
HeCAck much more closely bounds the alpha particle peak. On quiet days,
alphas from the Am241 source dominate the instrument counting
rate. 

Excluding the He4cal rate from a spectrum substantially eliminates
contamination by the calibration alphas. Alternatively, the external He
rate in He4cal may be calculated by subtracting an average value of He4cal
for quiet days. 

He8 spans He3, He4cal and He5 to provide a He flux at a mean energy of 1.4
MeV/nuc. He8 includes the calibration alpha rate.


Heavy ion rates in the solid state detector high gain mode:

When the low gain solid state detectors are in the high gain mode, the
maximum measurable energy decreases. This enhances detection of He at
the expense of high energy heavy ions. The following rates are available
in this ssd high gain mode:

Fe1
Mg1
Ne1
O1, O2
ClowE, C1, C2 
He1, He2, He3, He4cal, He5, He6, He8, HeCAck
H1, H2, H3

Periods when the instrument was in high-gain mode are
   2000-070 to 2000-318

"LowE" rates:

The rates with the "lowE" designation should always be used with caution.
These rates may be contaminated by other ions, and the level of
contamination may depend on the pressure in the proportional counter.
The reason for this is as follows. The instrument consists of a
proportional counter/solid state detector telescope. Ion species are
identified by the energy they deposit in each detector. At certain low
energies, the ion species are difficult to distinguish from one
another. The "lowE" rates extend as far as possible into this energy
range. As the pressure changes, the limiting energy for species
identification changes somewhat and the automatic flux calculation
algorithm may improperly include other species.