Dear Einstein Toolkit (ET) users,

As part of an NSF software award, we are planning to build an open, community data repository for the Einstein Toolkit (ET). A core driver for this repository is to facilitate data retention and sharing. Datasets produced by the Einstein Toolkit will be archived in an open repository where they can be connected to publications via a DOI, and searched for via metadata. We would welcome hearing your thoughts on how to share and sustain the datasets produced by the ET.

You are invited to participate in this research project because you are the user of the Einstein Toolkit and associated data. Your participation in this research study is *voluntary*. You may choose not to participate. If you decide to participate in this research survey https://docs.google.com/forms/d/e/1FAIpQLSdLrcXVJXKZBv3PAIaXtgj6YMylPVxwx-ctix8T0hf-XvhiUA/formResponse (and a follow-up survey), you may withdraw at any time. If you decide not to participate in this study or if you withdraw from participating at any time, you will not be penalized.

The procedure involves filling an online survey that will take approximately 20 minutes. Your responses will be *confidential* and we do not collect identifying information such as your name, email address or IP address. The survey (and a follow-up survey) questions will be about how you managed your simulation data regularly and related experience with using other data repositories.

We will do our best to keep your information confidential. All data is stored in an electronic format. To help protect your confidentiality, the surveys will not contain information that will personally identify you. The results of this study will be used for scholarly purposes only and may be shared with related project personnels.

If you have any questions about the research study, please contact Gabrielle Allen (gdallen@illinois.edu), Roland Hass (rhaas@illinois.edu) or Qian Zhang (zqian1@illinois.edu).

This research has been reviewed according to University of Illinois at Urbana-Champaign IRB procedures for research involving human subjects. If you have any questions about your rights as a participant in this study or any concerns or complaints, please contact the University of Illinois Office for the Protection of Research Subjects at 217-333-2670 <(217)%20333-2670> or via email at irb@illinois.edu.

The *link* to the survey is *here* https://docs.google.com/forms/d/e/1FAIpQLSdLrcXVJXKZBv3PAIaXtgj6YMylPVxwx-ctix8T0hf-XvhiUA/formResponse (the same link as above). Please complete the survey by the end of *next Sunday, August 13*.

Thank you very much!

Qian