Hello all, I am a newbie to ROOT. I am currently working on a code I discovered online. My aim is to construct a Positron Emitting Tomography Ring. By employing the code below, I managed to create two opposite photodetectors with an angle 180 degrees. However, I want to create an entire ring compos…

Hi, you can use a tube shape to define the ring containing detector elements. Volumes can be divided along some coordinate, in particular tubes can be divided in phi, creating replicated sectors. Then placing your detector in the common sector volume places it automatically symmetrically all over th…

Hello, thank you so very much for your response, I have been studying it for several hours and for the detector to be placed in the common sector I have made a change such as: sector->AddNode(D, 1, new TGeoTranslation(93,-3.6,-3.6)); (It was 41.5 before). I hope this is the correct change. Right now…

The constraints you seem to have is the number of detector modules (24 and not 100) and the fact that they are touching on the inner radius part of the detector ring. From these you can easily extract the geometry parameters of the ring (and detector modules) and the way to divide it. From the desig…

Thank you for your reply. I studied your guidance and thought of calculating the translation in the following manner for simplicity (as I am a newly learning ROOT). I employed the “circumference of a circle” formula with an unknown radius and equated it to total length of the detectors such as : 2p…

Hello @agheata , sorry for bothering you so frequently. In my last reply (11h ago) I thought that the construction was okay and terminated. However, now, I wanted to check again but remarked that the detectors are not fully in touch, there are small distances between them as in the image. [Ekran R…

additionally, I get the error “Warning in TGeoManager::CheckGeometry : Volume “COMP” has no medium: assigned dummy medium and material” Is there any way I can fix this? Thank you very much @agheata

[image] Posting code? Read this first! ROOT This is more addressed to the newer people of this forum, but I think it would be a good refresher for some. USE CODE TAGS!!! What is so special about these things? For one, they help show where you code begins and ends. Plus i…

Hi, To position correctly the scintillator crystals in your detector D, consider the following: D is a container volume, whatever you put inside it has to fit the box, but also the different placements of D itself should not overlap each other. Try to make D if possible fitting exactly the conten…

Simply create comp volume providing a TGeoMedium pointer to the constructor.

Creating Multiple Copies of a Composite Shape

Geometry

bellenot January 26, 2022, 10:06am 10