PARSEC
Last modification: 8 Apr 2014
Frequently Asked
Questions
- I generate uniformly 10000 cosmic rays and deflect them using
the function "transformCosmicRay" - why do I obtain only ~ 60
events?
The reason is the suppression of the flux in certain directions. The
efficiency of the whole lens is governed by the direction with the
strongest suppression, as otherwise artificial anisotropies would be
created. As the lens should also not distort the spectrum, this is
constant for all energies. You get the correct spectrum if you
normalize your lens with MagneticLens::normalizeLens(). If
distortions of the spectrum are irrelevant for your analysis, e.g. if
you distribute data according to a predefined spectrum on the maps,
you can increase the performance by a factor up to ~20 by using
MagneticLens::normalizeLensparts(). This normalizes the matrix for
each energy separately.
- Is it possible to easily access to the matrix elements to
transform a whole probability map and not deflect CRs event by event
?
The magnetic lenses are actually designed for this usage. However, as healpix
is lacking an own namespace and is thus difficult to integrate with some other
software, and also does not allow a low-level write access to its data,
this feature is directly available only for pxl:HealpixMap, which is a
(mostly copy and paste) reimplementation of the Healpix RING scheme.