25. Online textbook

This online textbook aims to help new Belle II members to get started with the software by following through a series of hands-on lessons.

We want YOU to contribute to this book!

If you are an expert of some topics, please share your knowledge! This is not only an act of altruism: Your contribution will

  • save you from having to answer the same questions over and over again

  • bring your students up to speed fast, so they can work for you and not the other way round

  • make people use your code/modules/work more readily

  • contribute to the success of this collaboration (you’re a stakeholder)

If you are a newcomer, please help to improve this material! You know where this book is lacking. Precisely at the parts where you’re feeling stuck or left alone! Tell us and we can fix it together! This is not only an act of altruism:

  • Let’s face it, passively reading through tons of new stuff can be incredibly tiresome. But you can change that! By trying to fix things here, you are much more actively working with the topics and deepen your knowledge while gaining hands on experience with our collaborative tools and software!

  • Having your first commit in the software framework should really be considered to be a rite of passage.

  • You also get your questions answered and people will thank you for raising them!

  • If you’ve already read our bylaws, then you know that in order to become an author of the Belle/Belle II papers, you need to complete quite a bit of service work (basically work that you cannot publish in a journal but that is required for the collaboration). Any work you do on training and documentation counts towards that goal as well!

Learn more about this: How to contribute.


Just as there are many versions of the Belle 2 software, there are many versions of this documentation to match it. After all, if a new feature is added in our software, we also want to have the documentation for it.

The current version of this documentation is shown on the top left of this page, just below the logo. You can also change your version by clicking on other versions.

If you are a new to all of this, we recommend you to select the recommended release version (release-xx-xx-xx (recommended) in the above list).

You can also take a sneak peek at the most recent version of the documentation by selecting the development version. However not all of the code examples might work for you yet.

The earliest release version which contains this online book is release-05-01-12.


If you change the version to an earlier version than the current one, some pages (also this page!) might not exist.


If you read the documentation of a newer version than the software that you use (in particular the development version), you might not yet be able to use some of the features shown.


If you get stuck or have any questions to the online book material, the #starterkit-workshop channel in our chat is full of nice people who will provide fast help. However this is not the place for specific or very detailed questions about your own analysis.

The first lesson of this book (Collaborative Tools.) will show several other places where you can get help later on. It also includes a quick tips section about the chat: Asking a question in #starterkit-workshop.