Inputs to this FAQ list are welcome. Please send them to Dr. Heiner Klinkrad.
Question:
While processing a flux analysis in the target orbit
scenario, the MASTER-2005 flux browser issued the warning: 'Valid
On-line Cell Passage buffer dimension reached during flux shooting!'
What does it mean and how are my flux results affected by this
warning?
Answer
The MASTER-2005 flux browser computes debris fluxes based on a
stochastic population reproduction. During this calculation process a
situation may occur where the flux shooting fails to reach a
pre-defined standard deviation for a certain debris source and
diameter threshold. If the flux browser issues this warning, your
computation result may differ more than 10 percent compared to a
deterministic flux calculation approach. You may try to use a slightly
different target orbit for your analysis, e.g. use a different value
for the right asc. of asc. node (the software averages over this value
anyway) or slightly increase the eccentricity if your initial value
was very close or equal to 0.
Question:
What size thresholds of debris populations are considered
for the past, present, and future population scenarios?
Answer:
For epochs from 1957 until 2005 (May) objects larger than 1
micro-meter can be considered. For epochs from 2005 (Jun) up to 2055,
objects larger than 1 mm may be taken into account.
Question:
I would like to run the MASTER-2005 application from
within another software. Is this possible?
Answer:
Yes, callable subroutine versions of the MASTER-2005
application are available for all supported platforms. The calling
interface is a Fortran Double Precision Function. The calling module
is provided as source code, that needs to be compiled and linked with
equally provided library files. The compilers and compiler options
used to generate these libraries are explained in the software
documentation on the DVD. Requests should be directed to the point of
contact given on top of this page. Please note that no support can be
provided for the installation process. Moreover, the callable modules
should not be embedded into large, complex software systems, since
conflicts e.g. with reserved COMMON blocks might result. Insight into
the source code to resolve such conflicts cannot be provided.
Question:
What time steps are used for debris populations
snapshots for the past, present, and future population scenarios?
Answer:
For epochs from 1957 until 2005 (May) population
snapshots are provided at 3 months intervals. For epochs from 2005
(June) up to 2055 population snapshots are provided in 1 year
intervals, centred on May 1 of each year.
Question:
Do the resulting fluxes for a specified analysis time
interval give the mean flux levels, or a flux level at a particular
instant (e.g. at the begin, center, or end of the interval)?
Answer:
The given fluxes provide mean levels, averaged by
integration over piecewise constant flux conditions (around snapshot
epochs), for the analysis time span, in such a way that the fluence =
(mean flux) x (total time span), is correctly represented. Attention
must by paid for integration time spans which are crossing the time
mark of May 1, 2005, since for earlier epochs, the minimum model size
threshold is 1 micron, while for later epochs, it is 1 mm. Please
observe error messages and warnings.
Question:
What is the difference between Global flux and Total
flux in the MASTER output files?
Answer:
Total flux only refers to the respective spectrum and the
chosen parameter range of that spectrum. Global flux is the overall
flux calculated by MASTER.
