ACE/ULEIS Release Notes:

      The following are cumulative release notes for the ACE Ultra 
      Low Energy Isotope Spectrometer (ULEIS) Level-2 datasets.  As 
      new datasets are released or old datasets are processed, this 
      file will be extended.   The assessment of data quality, such 
      as for  instrument  saturations,  represents the best current
      knowledge and may be retroactively updated in future releases.

=============================================================================

Time periods of significance to the Level-2 data are as follows:

  1998-120 02:00 - 1998-120 06:00  Instrument saturation.
  1998-121 18:00 - 1998-122 00:00  Instrument saturation.
  1998-124 01:00 - 1998-125 05:00  Instrument saturation.
  1998-125 06:00 - 1998-125 12:00  Instrument saturation.
  1998-161 16:50 - 1998-167 16:35  No data due to possible C&DH reset problem.
  1998-226 18:12 - 1998-226 19:21  No data due instrument commanding.
  1998-227 14:18 - 1998-227 16:55  No data due instrument commanding.
  1998-237 15:00 - 1998-240 00:00  Instrument saturation.
  1998-267 21:30 - 1998-268 05:00  Instrument saturation.
  1998-317 15:00 - 1998-324 19:10  No data due to Leonid shower protection.
  1999-023 00:00 - 1999-024 00:00  Instrument saturation.
  1999-049 00:00 - 1999-049 12:00  Instrument saturation.
  1999-125 00:00 - 1999-127 00:00  Instrument saturation.  
  1999-177 04:00 - 1999-178 16:00  Instrument saturation.  
  1999-255 00:00 - 1999-255 18:00  Instrument saturation.  
  1999-258 12:00 - 1999-259 06:00  Instrument saturation.  
  1999-265 06:00 - 1999-266 00:00  Instrument saturation.  
  1999-293 22:00 - 1999-294 06:00  Instrument saturation.  
  1999-323 18:00 - 1999-324 18:00  Instrument saturation.    
  1999-346 18:00 - 1999-347 12:00  Instrument saturation.    
  2000-027 18:00 - 2000-028 12:00  Instrument saturation.
  2000-042 06:00 - 2000-044 00:00  Instrument saturation.  
  2000-047 13:15 - 2000-049 09:45  No data due to instrument commanding.
  2000-097 12:00 - 2000-098 00:00  Instrument saturation.  
  2000-108 16:00 - 2000-109 17:00  Instrument calibration mode; no science data
  2000-116 15:00 - 2000-118 00:00  Instrument commanding.
  2000-160 06:00 - 2000-161 00:00  Instrument saturation.
  2000-175 12:00 - 2000-175 18:00  Instrument saturation.
  2000-195 06:00 - 2000-198 00:00  Instrument saturation.
  2000-261 12:00 - 2000-262 00:00  Instrument saturation.
  2000-314 00:00 - 2000-315 06:00  Instrument saturation.
  2001-090 00:00 - 2001-090 06:00  Instrument saturation.
  2001-101 12:00 - 2001-101 16:00  Instrument saturation.
  2001-118 00:00 - 2001-118 18:00  Instrument saturation.
  2001-268 18:00 - 2001-270 06:00  Instrument saturation.
  2001-282 17:25 - 2001-283 22:10  Instrument commanding.
  2001-294 12:00 - 2001-295 00:00  Instrument saturation.
  2001-299 16:20                   Automatic aperture door operation commenced 
                                   (see entry below for October 26, 2001). 
  2003-301 10:20 - 2003-302 13:00  Approximate period in which the instrument 
                                   had significant dead time due to high count 
                                   rates.  During this time, the dead time 
                                   varied, with a maximum value of about 83%
                                   during the most intense portions of the event.


=============================================================================
October 26, 2001:

Automatic door operation commenced on Oct 26 (DOY 299), 2001, and greatly 
reduces the incidence of saturation and loss of MCP gain during intense events.
When the door moves to change the size of the entrance aperture of the 
instrument, the door location is telemetered in the instrument housekeeping 
data.  Existing software automatically adjusts the instrument geometry factor 
for such periods, and so the ULEIS Level 2 fluxes at the ASC need no correction
for door motion.

=============================================================================
August 21, 2008:

release of new version of uleis intensities, generated with udf_lister
program including all efficiency updates.  List of instrument saturations
updated;  several additional periods added.  

=============================================================================
Nov. 6, 2009

release of modified uleis intensities for Bartels rotations 2373-2404 to correct
for a decrease in efficiency for H and He.  Other species are not affected.

=============================================================================
April 20, 2012