I realized that my choice of topmost altitude was the one causing a problem here. I managed to get rid of that though by setting to 6.5e8.
I also want to reproduce some results from literature to validate the model. However I have a few issues:
I see that my earth is very large so much that I doubt that I really obtained the expected a “local geometry”.
Is my assumption correct?
Also, I want to assume that this gives rise to prolonged simulation time.
How do I convince myself that the geometry contains only a slice of the atmosphere centred at position of my interest?
In the file with an extension .err, there is error message which is similar to Geofar error message. What is surprising me is that I still get the same message when I run an example distributed with package even though there is more of the same error in my file. I am just worried that this might extend simulation time. How to go about it?
There is still struggle in understanding the normalisation of my results. Could you please explain how I could obtain differential flux in cm^-2 s^-1 MeV^-1 when using the USRTRACK? Do I get results normalised to this units already or not?
Since you did not upload any file, I assume you are still working on the inp file you have enclosed in this post: Cosmic ray showers.
As Francesco pointed out, there was an error in the geometry, which I understood you have solved by increasing the topmost altitude for particle tracking.
I have rebuilt the local atmosphere and it seems to me that the geometry is correctly reproduced being the AIR/SIDE layers now properly defined. I attach the files: atmloc.zip (4.3 KB)
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For what concern the normalization, this topic has been widely discussed in several posts in this forum, which I recommend you to have a look.
In essence, if you ask for a scoring in one of the standard AIR layer, FLUKA knows the normalization factor to apply via the *.sur file, generated at the moment of the creation of the atmloc. Note that in this case you should rename the *.sur* accordingly to the *.spc* set of file you are using (e.g. phi0465.sur if you use the xxphi0465.spc set). However, if you plan to modify the geometry for any reason (e.g you want to include new regions in the atmloc geometry), FLUKA will not know the normalization factor for the new regions you will create. In this case, the option NO-NORM fits better, by leaving to the user the normalization of the results in post-process (see the posts I have linked).
Thanks for your response.
I attach a folder containing my input. file.zip (16.5 KB)
The goal is to determine the muon flux as an integral value (and flux of other particles like neutrons) at different altitudes in my location, starting from 0 km (level surface), and check how the muon flux at the surface compares to the globally known muon flux of approximately 60 cm^-2 min^-1.
Later on, I plan to use the muon energy spectrum determined from this model as a source to perform a different simulation where muons will be propagated deep underground. This means I do not need to use NO-NORM.
Please check my input and see what I mean by large earth, when I am only interested in my location (which I believe should be smaller, relative to the whole earth
I am a bit confused from the file naming convention you used. It looks to me that you have created your own atmloc, but then renamed as the one provided with the FLUKA distribution (36n140e.geo)… I am right? Did you use the same parameters described in here?
Please note that the angular span between the two cones labelled “cutone2/3” contains the atmosphere of interest for the latitude of interest, while the third cone (cutcone) delimit the “side” regions (since placed in the opposite direction wrt to the other cones). Please refer to Figure 17 of the manual.
Yes you’re right. I created my own atomloc and renamed as the one provided with the FLUKA distribution.
The topmost altitude for particle tracking (which I see as the radius of my vacuum space) chosen as 1e10 did not make sense and was the cause of geometry error in the definition of the EarBLK region because it coincided with the radius of the black hole so I chose 7.0e8 to be my topmost altitude.
Geographic coordinates are still the same: -33 as latitude and 18 as longitude and geomagnetic cut off is 1.0 GeV, altitude of 0.0 km.
Geographic coordinates are still the same: -33 as latitude and 18 as longitude and geomagnetic cut off is 1.0 GeV, altitude of 0.0 km.
I think I am winning so far because I obtained a bit smaller earth than before. Looking forward to a smooth simulation.
Once more, please have a look to the files I linked above. I have used very similar parameters and I indeed got a local geometry which is smaller that what you have provided in your last post. So that, I think the two input files should be pretty much similar (geometry-wise).