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Hello,

How is everyone doing with the little ROOT challenge exercise? Were you able to identify the hidden resonance?

There is one of you who has already made quite some progress and is almost finished with it!

Please keep me updated and/or send me any interesting plots you may have.

Thanks.

-Edgar

So, maybe it’s a little early to start thinking about the physics GRE, but maybe not. I realize we haven’t started out work yet so we don’t know our schedules, but maybe it’s possible to do about an hour a week of GRE prep?

We could also use this time to go over stuff from out ED and QM lectures that we may not have understood.
I have a list of major concepts that we need to know for the physics GRE and a site with practice problems. Let me know if anyone else is interested in meeting. I was thinking of starting Friday maybe at 11 or 12 before our physics work and CERN work picks up.

Anybody interested?

-Andrea

(Also, on an unrelated topic, Benedikt Hegner said that he was gonna cancel class tomorrow because he is not feeling well and we can reschedule for some other time.)

Hi,
Does anyone remember/know the exact difference between “Row” and “Instance”? Is “Instance” the event number in one run? I don’t really understand the terminology.

Hi everyone,,

So, I am trying to do the trigger part. And the way I did is to select the useful elements in the leaves needed (e.g. from the leaf mu_py, I want a list of elements that satisfies the trigger threshold (?)) And the num_entries drop from 30839 to 2988… Attached is the 3 plots, the top one in the right is the raw mu_py, the top left one is selected mu_py…The bottom one is the fitted hinvm (hist of inv mass)…I don’t know if it makes sense… the top right one is kinda suspicious, especially everything is in one bin..(but maybe it was my code.) And I don’t think the bottom one is right either… I would expect a guassian curve (bec we are asked to fit with gaus and it would make sense to be a gaussian with a mean value of particle’s mass…) but i can’t tell where is wrong…

Elim =D

Hi, sorry for posting too many questions…

I forget the Draw command includes the “trg_L1MuOpen” and it has already been erased in my history…
If anyone know, please let me know…

Thanks. Elim =D

Does anyone know what it means??

Thanks, Elim =D

Hi Edgar,

I am confused by the structure of the tree. Is it that each instance has an array of pt or that each instance has 1 value for mu_pt?
If it is an array, why would it be? Is it because pt is changing with time? But then, what does its histogram represent? is it representing what is the highest pt of the muon had?
If it is a single value, what is the point of drawing a histogram? (from the formula of inv_m, I will only get a single value)

Also, what is runno (the run number) in the muons.root?

Thanks, Elim =D

Hi,

I have difficulty opening the muons.root file and the macros file. For the macros file: if I use wget in the linux terminal it says “authorization failed”. If I try to copy the code into an emacs file and then move it to the root/macros directory so that I can access it in root, it does not work either. It says permission denied.
In addition, I can only open muons.root by clicking on it, which brings up root with the file in it. This is fine, but I need to be able to access the macros file or any .C file I create too. Can anyone help?

Thanks,
Chelsea

Hello,
So I am having problems opening ROOT in lxplus. If I just call ROOT by typing “root” it says that the command isn’t found even though I am in the right directory and I have ROOT in there. I have tried typing “./root &” since that is how I open ispy in lxplus but that says Permission Denied. I have tried “chmod +x root” but it doesn’t change anything. Do you know what I am doing wrong? I am probably making a simple mistake since I don’t know many linux commands.

Andrea

Hi Edgar,
I was working on trying to figure out which muons are the hardest muons. Are the hardest muons the ones with the most energy? I scanned “mu_e”, but I can’t tell which muons have the highest energy because it seems scattered throughout the events.. I’m not sure if what I said makes sense.. I also thought that if I drew “mu_e” it would help me figure out which muons had the highest energy, but it plots the number of muons that had a particular energy, not which muon had what energy..right?
I’m aware that there is a GetMaximum function in TTree, but it won’t tell us which event produced the maximum energy..so will that help us?

Thank you,
Ashley