How to get Kshort selection after Roofit?

[Vikas_Raj]

Dear ROOT Forum,

I have successfully used roofit to fit the two kshorts in my decay channel( using the invariant mass variable to use roofit!). Now, what can I do after this?
Like, I got a peak-like region in both the Kshorts, and the width is also different for the two. How, can I do Kshort selection using mass (or any other kinematic variables like flight length etc…)?

I thought that you first do the selections when generating the ‘.root’ file and then roofit, right? is that not the case?
Kindly find the attached roofits as reference! ( I have only the signal mc file, no data!)

Any help or valuable insights on how to proceed after this would be greatly appreciated!!!
Thank You !

[jonas]

Hi @Vikas_Raj,

I’m afraid that we can’t answer this question here, that really depends on the analysis you want to do I’d suggest you consult your colleagues and supervisors to figure out the next steps. Then, if you need technical support for realizing these steps, you can ask here.

Cheers,
Jonas

[Vikas_Raj]

Hi,
I got the selection but how can I test it’s efficiency and purity?
Like I have the signal MC, and did the selections, how can we get get number iof Signal events, background events etc??
with only signal mc, as a first test for the decay channel?