Helium Mass Spectrograms from ULEIS and SIS

2007
2006
2005
2004
2003
2002
2001
2000
1999
1998
1997

The PDF files may be downloaded via anonymous ftp,
from mussel.srl.caltech.edu in the directory: pub/ace/level3/sis/heplots/

Generally a larger file size contains more interesting data.

Helium mass spectrograms are based on data from the ACE/ULEIS [1] and
ACE/SIS [2] instruments.  They can be used to identify periods in
which enhanced intensities of 3He indicate the presence of material
from impulsive solar energetic particle events [3].

The files with names of the form he_xxxx.pdf contain He mass
spectrograms (measured He mass versus time) for individual Bartels
rotations.  The "xxxx" in the file name is the rotation number.
The upper four panels are spectrograms corresponding to four different
energy ranges, two from the ACE/ULEIS instrument and two from the
ACE/SIS instrument as follows:

     panel 1    0.2 to  0.4 MeV/nuc from ULEIS
     panel 2    0.4 to  1.0 MeV/nuc from ULEIS
     panel 3    4.5 to  7.6 MeV/nuc from SIS
     panel 4    7.6 to 16.3 MeV/nuc from SIS

The plots are based on raw event data without any corrections for
livetime, efficiency, or other systematics.

In regions of the plot where the density of events is relatively low
(less than or equal to 10 events/hour/0.05 mass unit), each detected
He particle is indicated by a dot.  Where the event density is too
high for individual dots to be distinguishable the density is
indicated by a logarithmic color scale with adjacent colors
corresponding to event densities differing by a factor of 2.

Panels 5 and 6 are included to provide context information.  Panel 5
shows the electron intensities at two different energies
(approximately 45 and 235 keV) from ACE/EPAM [4].  These intensities
are obtained from the ACE/EPAM level 2 data set.

Panel 6 shows data obtained from the NOAA/SEC ftp site [5].  The red
curve (left-hand scale) shows 1-8 Angstrom x-ray intensity measured by
the GOES satellites.  Black curves show longitude (right-hand scale)
versus time for solar active regions.  Solid, dotted, and dashed lines
indicate active region latitudes in the ranges -20 to 20 degrees, 20
to 90 degrees, and -20 to -90 degrees, respectively.  The circled +
signs indicate x-ray flares, with the diameter of the circle
proportional to the logarithm of the peak x-ray intensity.  For flares
that have been associated with a particular active region, the point
is plotted along the curve for that active region.  For flares without
such an association the points are plotted along the bottom axis of
the plot.


References: 

1. Mason, G.M., et al., "The Ultra-Low-Energy Isotope Spectrometer
   (ULEIS) for the ACE Spacecraft", Space Science Reviews, 86, 409-448
   (1998).

2. Stone, E.C. et al., "The Solar Isotope Spectrometer for the
   Advanced Composition Explorer", Space Science Reviews, 86, 357-408
   (1998).

3. Wiedenbeck, M.E., et al., "How Common in Energetic 3He in the Inner
   Heliosphere?", Solar Wind Ten (M. Velli et al., eds.), AIP
   Conf. Series #679, 652-655 (2003).

4. Gold, R.E. et al., "Electron, Proton, and Alpha Monitor on the
   Advanced Composition Explorer Spacecraft", Space Science Reviews,
   86, 541-562 (1998).

5. ftp.sec.noaa.gov  Flare identifications from /pub/indices/events,
   active region locations from /pub/forecasts/SRS, x-ray intensities
   from /pub/lists/xray

Helium Mass Spectrograms from ULEIS and SIS for year 1997

Bartels Rotation
Start Date:
File size

yyyy/doy
mm/dd/yy

2245
1997/361
12/27/97
712858

2244
1997/334
11/30/97
458289

2243
1997/307
11/03/97
2443788

Bartels Rotation
Start Date:
File size

yyyy/doy
mm/dd/yy

2242
1997/280
10/07/97
1172049

2241
1997/253
09/10/97
458085