Liceo S.G. Calasanzio of Carcare INTRODUCTION TO ROOT Liceo S.G. Calasanzio of Carcare Represented by: Fracchia Caterina Rinaldi Marco Profssa Occhetto Michela

ROOT is a modular scientific software framework ROOT is a modular scientific software framework. It provides all the functionalities needed to deal with big data processing, statistical analysis, visualisation and storage. It is mainly written in C++. ROOT was a software developed by CERN and it was initiated by René Brun and Fons Rademakers in 1994.

A key feature of ROOT is a data container called tree, with its substructures branches and leaves. A tree can be seen as a sliding window to the raw data, as stored in a file. ROOT is designed for high computing efficiency, as it is required to process data from the Large Hadron Collider's experiments.

Although the infinitive program’s functions, we are able only to realise experimental graphics and we are able to fit them with basic functions like linear functions and parables. This program deal with different unity of work called “classes” and the first we explain is TGraphErrors.

In this moment ROOT has realised our graphic, but it doesn’t show it In this moment ROOT has realised our graphic, but it doesn’t show it. To see this graphic we have to use the method .Draw(“AP”) and we obtain the following screen. To set the title it’s enough to write graphname.SetTitle(“Title”).

Now we have to fit the graphic verifying that experimental data are conformed with the theoretical one. The relation that we are used to find is a line or an parable. and to do that we have to use TF1 class. This class deal with function with only one independent variable and we obtain the following screen.

At the end we want to visualise the parameters’ values composed by “Chi- Square” and the parameters correlated to the previous function (line or parable). f(x)=ax+b line f(x)=ax2+bx+c parable

For more information you may refer to his link: https://drive.google.com/file/d/1j136x_aw8gE3-bLs29fm1vfJRNg6ZVTJ/view?usp=sharing https://drive.google.com/file/d/1x2UzHLFrN-TtWgpzRBASy-Cz-UyBgPVX/view?usp=sharing

Liceo s.g.calasanzio Thanks for your attention.