Why 2 ComponentAnalyticField objects are used in the example AliceTPC?

Garfield++
1

As the title, Why 2 ComponentAnalyticField objects are used in the example AliceTPC?

ComponentAnalyticField cmpe;
ComponentAnalyticField cmpi;
2

Dear @newconcept1979,

Maybe the corresponding example of the webpage might help.

Let us know if this clarifies it.

Kind regards,

Djunes

3

@djjansse, i viewed the introduction of the webpage for this example, there is no information about why two ComponentAnalyticField objects are used.

but i think “cmpe“ is used for electron drift and “cmpi“ is used for ion drift. and the electric field is different for electron drift and ion drift.

4

Hi,
your understanding is correct. You can find the explanation under the heading “III - Defining the MWPC layout” of the page that @djjansse pointed you to:

We start with the component describing the electric field used for the drifting of electrons, which pass through the open gating. Later on, we will use another component for ions, which drift under closed gating.