We use cookies to help provide you with the best possible online experience. Learn more


Master’s Thesis, Optimization 1

We offer a master’s thesis position at our research department at our head office in central Stockholm. The aim of this thesis project is to develop algorithms that exploit unused degrees of freedom in optimization of radiation therapy, specifically for arc beams. Key tasks include formulating tractable optimization problems to utilize the degrees of freedom, implementing the problems in Matlab or C++, and analyzing the results in RayStation: our radiation therapy treatment planning system that is used at hundreds of clinics worldwide.


Background and purpose

A majority of cancer patients undergo radiation therapy as part of their treatment. Optimization is used to shape the distribution of the therapeutic dose in a way that minimizes the risk for adverse effects while ensuring that the disease is cured. Delivering radiation by a beam swept in one or a few arcs over the patient is becoming increasingly common. Currently, arcs are mainly delivered from user-selected planes and with user-selected fixed angles for the collimator that is used to shape the varying beam aperture throughout the arc.

The goal of this project is to create algorithms that automatically select the arc planes and determine varying collimator angles. Challenges include implementing automated analysis of the patient geometry and inventing heuristics for finding good solutions to the beam orientation optimization problem. Utilizing the unused degrees of freedom has the potential to improve the dose distributions of the treatment plans and thereby lead to higher probabilities of curative treatments without side effects.


About the department

The responsibility of the research department is to take brilliant ideas on how to advance radiotherapy planning and turn them into software prototypes. Promising prototypes are then further refined by the development department to be parts of our advanced software for radiotherapy planning. The research department is also involved in several research collaborations with clinical cancer centers all over the world.


Education and Experience 

  • This master’s thesis project is suitable for degrees in applied and computational mathematics, engineering physics, computer science, or similar programs where you have excelled.
  • Experience in optimization techniques is an advantage.


  • Fluent in Swedish and English
  • Programming skills including C++
  • Programming skills in Python and C# is an advantage 


Personal profile

In order to be successful you should be able to take your own initiatives and take responsibility for your work tasks. We would like to see that you are flexible and easily adapt to changes, and that you are meticulous in your work so that tasks are thoroughly completed. It is important that you have an analytical approach to problem-solving. As a person you should be optimistic and like to work both independently and in a group.

Working at RaySearch

RaySearch, a world leader in the field of advanced software for radiation therapy, offers a workplace with an open and positive atmosphere, where learning, creativity and collaborations are highly valued. Located in central Stockholm, RaySearch provides you with a unique opportunity to work in a fast growing, international company where you can be proud of the products and solutions that the company work towards. Read more about RaySearch.

Apply for this vacant position 

You are welcome to send your application marked with “Master’s Thesis, Optimization 1” as soon as possible by clicking on the button below or by sending an email to work@raysearchlabs.com. Please include a resume, transcript of university records and any relevant scientific publications such as your bachelor thesis report and possible published papers. The selection and interviewing process will be ongoing.

For further questions please contact Kjell Eriksson, Chief Science Officer.