Master's thesis results used to publish a new research paper?
You should normally be a co-author if you contributed a substantial amount of data (and be invited to at least check the paper before submission), but apparently the authors of the paper decided that your contribution was not big enough. It is hard to judge if they are right without knowing the details of who contributed what exactly.

If you are not co-author, an acknowledgement is perfectly normal: A Master thesis is usually not publicly available so there is no point to cite it. This also answers your first question: yes, it is fine to publish results from an MSc thesis in a paper.