These plots show the calculated nuclear charge Z as a function of detection time for each pulseheight-analyzed particle recorded by SIS. Standard data cuts were applied requiring that particles stop in the instrument and that multiple calculations of Z using different combinations of energy-loss measurements be consistent in order to reject interacting particles and/or chance coincidences of multiple particles. Time periods for each plot are on Bartels rotation boundaries, and each time period is represented by 4 plots, covering SIS ranges 0, 1, 2 & 3, and 4-7. This corresponds to a different energy interval for each element. For oxygen, the plots approximately represent 7.1-10.0, 10.0-13.1, 13.1-21.0, and 21.0-89.8 MeV/nucleon, while for iron the intervals are approximately 10.5-15.8, 15.8-21.5, 21.5-36.3, and 36.3-167.7 MeV/nucleon; see here for corresponding energy intervals of other abundant elements.

The purpose of these plots is to quickly determine periods which are interesting from a compositional standpoint, for example periods which are particularly iron-rich at high energies, or which had large measureable abundances of relatively rare species such as odd-Z elements or ultraheavy (Z>28) nuclei. Note that individual pulse height events have been plotted and there has been no correction for instrument livetime, thus absolute intensities cannot be determined from these plots; see SIS level 2 data for corrected absolute intensities of abundant elements. The lack of livetime correction can lead to some unusual artifacts during intense solar particle events; during the most extreme cases (such as the 14 July 2000 Bastille Day event) the density of plotted points actually drops at the peak of the event due to the greatly diminished livetime. Also, at all periods, helium (Z=2) is deliberately throttled by the instrument, resulting in a much lower density of points than would otherwise be the case. Finally, in spite of the data cuts, some background events and artifacts still remain, especially at low ranges (range 0 and range 1) at low Z (near He), where spurious tracks near Li (Z=3) sometimes appear.

These files can be downloaded via anonymous ftp, from   mussel.srl.caltech.edu   in the directory:   pub/ace/level3/sis/zvst/

Generally a larger file size contains more interesting data.