I am student from India and finished master's this year. I secured a PhD position at the Gottingen university in Mathematics. In my offer letter it is written, I will be employed from 1.10.2018 to 30.09.2021 as a research assistant at the mathematical institute of the George-August -Universitat Gottingen. I will be hired in part-time (19.9 hours/week) and paid according to E13 TV-L (minimum 1758.68 Euros per month).
Here someone have written that, with a TV-L position, getting student visa is not only problematic, but also something can't be fixed later. But it looks like I have a 50% position. In Germany people are are considered as a student from the perspective of social security (health insurance, pension, unemployment insurance), if work is less than 20 hours per week (for my case it is 19.9, as per contract). So I could be considered a student as well. I don't understand which Visa I should for. In India, the available long term Visas are the following: https://india.diplo.de/in-en/vertretungen/generalkonsulat3/-/2001158. I guess it should one of Student, Employment or Guest Scientist Visa. But I don't understand which one. This seems to be a very complicated stuff. Kindly look into this matter and let me know what should I do.