Hi group, I am a new user to EGSnrc.

Hi group, I am a new user to EGSnrc. I have gone through the getting started document and through some of the tutorials, but I am having trouble with a few things.

I have used BEAMnrc to create a geometry that I think represents the Varian Clinac iX geometry fairly well including: target; primary collimator; flattening filter; ionization chamber; mirror; and jaws (MLCs excluded). I have used the same settings for the main input parameters that are used in the “getting started” examples and I think I have a successful run. However, I am trying to view some information about the phase space file created using beamdp_gui but no matter what I do it just pops up a screen saying “Running beamdp …”. Does this indicate that there may be something wrong with my .egsphsp1 file?

Also is there a way using this method to get out a .ptracks file so that I can use egs_view to visualize that my geometry? I’d like to be able to visualize where the particles are going rather than just use the preview accelerator button.

I have the last 50 cm of my geometry defined as just a slab of water, what is the best way to get profile and pdd info out of this simulation? or would it be best to use ctcreate to create a water phantom and use DOSXYZnrc to evaluate this sort of data?

Thanks in advance, any help would be greatly appreciated!

Hi

Hi,

A follow up from my previous post. I have managed to compile egs_gui and egs_inprz, and they are working. However, egs_view seems to have compiled, but I am unable to load input files into it. It shuts down after I select an input file (e.g. the slab.egsinp file from the tutorial pdf).Has anyone else had this issue, and if so, how did you resolve it? I am using a Mac running High Sierra.

Hi

Hi,

I have been trying to install EGSnrc on a Mac running High Sierra. I am having problems opening egs_view. When I open egs_view manually, I get the following error message in a new terminal shell:

dyld: Library not loaded: /usr/local/opt/qt/lib/QtGui.framework/Versions/4/QtGui

Referenced from: /Users/orlamurphy1/Documents/EGSnrc-master/egs_home/bin/osx/egs_view

Reason: image not found

Abort trap: 6

logout

Saving session…

…copying shared history…

…saving history…truncating history files…

…completed.

I was reading through old posts, and found someone having a similar problem who was told to use the following:

brew uninstall qt

brew uninstall qt-legacy-formula

brew link qt@4

I have tried this, but I am still unable to open egs_view. Could anyone shed some light on what is going wrong here?

Hi everybody

Hi everybody,

I need your help for my installation of EGSnrc. I installed EGSnrc on linux several times and at the end of each installation I have shortcuts for egs_view, egs_gui and egs_inprz. someone can help me solve this problem. I also have a problem with “make”.

Hello to everybody

Hello to everybody,

I need your help for understanding the results of one of my simulations or for finding a mistake I perhaps made.

I scored the Air-Kerma and the absorbed dose to air for monoenergetic 2-MeV photons in egs_inprz over 7 meters. At each distance I observed a ratio between Air-Kerma and absorbed dose of round about 100. But because of the nearly CPE, I expected equality between Air-Kerma and absorbed dose (at least at any distance). Is the error in reasoning or is there something wrong with the simulation?

Thanks for your help!

Hi all.

Hi all.

I have next questions (I hope easy) for you.

1. When I executing my simulation (by typing ‘egs_brachy filename -p’) I see following information :

In EGS_Application::initSimulation()

EB_Application::createGeometry: no geometry specification in this input

Simulation stopped

Simulation geometry is opening in egs_view without any warnings and executing with flag ‘ -i ‘.

What’s going on? My phantom contains many geometries inscribed (via ndgeometry), but ‘ phantom geometries = [only base geometry of phantom] ‘ – it could be a reason? ‘Phantom geometries = ‘ indicates all geometries of phantom (base and inscribed/dimensions?) or only base geometry?

2. I need to obtain dose distribution, in which dose amount in TG-43 reference point is equal 1 Gy. There is any way to impose condition like that on simulation? Something like “stop simulation when dose in point (x,y,z) achieve 1 Gy”?

Thank you for any answer.