but i have to use these three gases in mixture what to do then?
You need to create a material named C2H2F4_iC4H10_SF6 with three components, and add C2H2F4, iC4H10, and SF6 as materials to it.
ok dear i’ll work on it then let you know. thanks for your time 
what about the density i have found the other two densities on the same manner as you told me. but how and where to put the density? 'cause we have only one line where we have put the density for c2h2f4 earlier.
To calculate the density of SF6 and isobutane, you can use exactly the same recipe as for C2H2F4. By the way, please check your calculation, maybe you meant to write CLHEP::mg / CLHEP::cm3 instead of CLHEP::g / CLHEP::cm3.
To calculate the density of the mixture, you can use the weighted average of the densities of the three components.
Don’t know what you mean by “where to put the density”. It’s the second argument in the constructor of G4Material, see, for instance
ok i got the answer thank you. yes dear i know the line i was just asking how to put the density of three different gases. you said a weighted average. one more thing as you told the way to calculate the density of c2h2f4 and i put that value and also a answer was in g / cm3 i changed this CLHEP::mg / CLHEP::cm3 .into g / cm3. and its working but issue is my laptop is on from 1 night and today is 2nd night and it still working for 1000 events and only 12 events are generated is there any issue with the program or it will take this much time?
yesterday at night laptop was off and now it is generating 13th event.
That is very slow. How many electrons do you typically get in the avalanche?
As I said in one of my earlier replies, you normally have to adjust the voltage on the wire if you change the gas composition.
in event 18 the avalanche size is 18 and in event 19 the avalanche size is 2. where to set the voltage and please tell me how can i find the out the specific voltage on wire for specific gas?
and dear if i put the three gas composition c2h2f4_ic4h10_sf6 then what will be the voltage?
post 84 (as you told me to find the weighted average of the densities that means i’ll find the densities of each gas as you told me the way then i’ll take average by adding three densities and divided by 3?
and i have put the gas and done this CLHEP::g / CLHEP::cm3. because answer was in g / cm3 is it ok or we have to follow the previous notation and change our answer in g/cm3? kindly guide me in this matter too.
You can use g / cm3 or convert to mg / cm3, as you want, 0.004 g / cm3 is equivalent to 4 mg / cm3.
By weighted average I meant: fraction of C2H2F4 * density of C2H2F4 + fraction of iC4H10 * density of iC4H10 + fraction of SF6 * density of SF6.
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Using the program I sent you (plot.C) you can calculate the average gain for a given wire voltage. Please use it to adjust the voltage to the value you want.
dear sorry but i didn’t understand how i will find the voltage for my gas file like for c2h2f4. but see the wire
geometry in the garfieldPhysics.cc is and i have changed the voltage from 1000 to 2000. independent of particle etc.
dear from the last day i have texted you about the issue system is working and 27 event generated today as i have also changed the voltage to 2000 V. is the speed ok or any issue still? can you help please.
problem which we are facing during geant4garfieldInterface we are using gas file c2h2f4 100% with voltage at wire 2000 volts and wire radius is 0.025 mm. and no. of events 1000. and also we have changed the PAIphot model to PAI and now using PAI model. and now the events which are generating are taking lot of time. as i told you earlier it is taking time like in 2 days by contineus laptop on 30 events are generated is this speed ok or any issue with it? laptop specs are high octa core and with 8GB RAM.
As I said before, this seems very slow to me. A possible reason could be that at the voltage settings and gas mixture you are using, the gas gain is very high and the avalanche simulation takes a long time. I would therefore suggest to first calculate the expected average gain with a simple standalone program. Instead of the compiling and running the plot.C program I sent you earlier (the title was perhaps a bit too confusing), you could do that using the attached python script. After setting up the environment, you can simply run it by typing python gain.py. You will of course need to adapt the name of the gas file and the voltage settings in the script.
If the gas gain you get from this script looks reasonable, then there might be another reason for the slowness of the program. If you send me the latest version of the files that you modified, I can take another look.
gain.py (1.0 KB)
ok dear i’ll send you all changes i have made now. one more thing the file you have sent me now. how to run this one means where to place it and etc can you explain little bit for me?
one thing in the example geant4 garfield inetrafce i have chnaged the physics.mac file and made the PAI model in the line.
then in the src file i have made changes in the garfieldphysics.cc and change the PAIphot model to PAI model you can see in the colored lines. and also my supervisor said to change the step size to 1e-2. but you told to set it to 1e-4. but we have changed it in the hope so that it works earlier cause its working too slow. and also changes the voltage to 3000. one more thing in the garfielddetector construction.cc file we changed the absorber material to G4_GLASS_Plate my supervisor sir said we may change it from Pb default to glass plate in the hope it work fast. these all are the changes. but in the end when i ran again the gain is zero and avalance size is also zero.
