Philosophy and guiding principles of the NuGrid collaboration
The NuGrid collaboration brings together expertise in stellar evolution, stellar explosions, nucleosynthesis, and nuclear physics to develop the tools and databases needed to calculate comprehensive nucleosynthetic yields and errors in these yields. Our core science goal is to provide a complete set of stellar evolution sequences for low-mass and massive stars with compatible input physics, including explosion simulations for a broad range of metallicity. We combine these sequences using a framework for massively parallel nucleosynthesis simulations with up-to-date and flexible nuclear physics input to produce a full grid (in mass and metallicity) of nucleosynthetic yields. As this data is produced, we will provide it to the open nuclear and astrophysics communities. We will also provide flexible tools to extract and analyze the trajectories and nucleosynthetic data.
The NuGrid tools, including the parallel network code and unpublished data, are available to NuGrid collaborators and participants (see Our Organizational Structure below). We are actively accepting new members into the collaboration.
We try to use a lightweight approach to the business of developing and maintaining the NuGrid collaboration. The collaboration is led by two principal investigators at any given time; we rotate these responsibilities among active members. We also recognize two broad styles of contribution: “collaboration” and “participation”.
NuGrid is a team effort, where collaboration members openly share science, applications, work organization and opportunities for involvement in NuGrid papers. The collaborators make up the core of this collaboration, contributing, where needed, to all core projects, codes, and database management. Collaborators have full access to the subversion repository containing all codes as well as the full NuGrid database.
A new collaborator will typically initially join the collaboration focusing on at least one well defined topic, or research area, working closely with one or more NuGrid collaborators. The expectation from the collaboration is that the new member is becoming an active player in carry on science projects, and/or further developing existing codes, and/or feeding the NuGrid library. In exchange, a new collaborator will have full support and collaboration from other NuGrid collaborators.
Published data including stellar sequences, explosive trajectories, and yields will be made available to the general public. Unpublished data and post-processing tools, will not be publicly available. Scientists can gain access to these tools or data for focused research projects. Such projects include nuclear physics analyses studying the impact of nuclear reaction rates in stellar or explosive trajectories and observational studies requiring new simulations to compare directly specific observations. These participant projects will be worked out on a case by case basis and the participant will work directly with at least one NuGrid “collaborator” who will ensure this project follows NuGrid guidelines. The projects will be detailed in the applications folder. For these projects, the participant will have access to any codes or tools necessary for the specific project.
Although many students and postdocs under the NuGrid collaboration will spend their time at a single institution, NuGrid offers the opportunity for students to spend time at multiple institutions with a broader mentor base. NuGrid has methods to fund the travel for these multi-institutional students, facilitating collaboration between NuGrid members (both collaborators and participants).
The software tools that we develop, and the data that we use as input and generate as output, are the focus of our effort and the primary products of our collaboration. Our software development effort is focused on a set of nuclear network codes and associated data management, analysis, and visualization tools for calculations of nucleosynthetic yields from all phases of stellar evolution and explosions. Our data are complete stellar evolution sequences, trajectories from simulations of stellar explosions, and the nucleosynthetic yields calculated from these sequences and trajectories.
If you want to use our codes or data directly, we ask that you follow a few rules. These are designed to foster a healthy collaborative environment, in which collaboration members can freely exchange ideas and results without fear of having contributions go unrecognized.
If any of these rules are difficult to apply in your specific situation, don’t worry. We welcome any form of collaboration; we just won’t be able to make all tools and unpublished data directly available to you. However, you’re welcome to work directly with any or all of us on projects that interest you; scientific input, direction, and collaboration is just as valuable as contributions to our specific tools and data. We’ll consider the technical needs of any project and judge how to handle data and software use on a case-by-case basis. Of course you’re always welcome to use any of our published data or publicly-released tools, and we’ll help you apply them to problems that interest you.
Research projects that take advantage of the NuGrid tools should be included in the NuGrid applications web page summarizing the goal of the project including a short abstract, a brief statement of the methods and goals, and a list of users and external collaborators. This description is required to allow communication between NuGrid collaborators. In the case of a participant led project, the associated collaborator is in charge of outlining this project. This communication facilitates contributions from the broader NuGrid collaborator network, producing better science. These projects will be discussed in NuGrid teleconferences when first introduced and, later, as needed.
All current collaborators will be part of the core paper I. But with subsequent papers, the policy will be to include any NuGrid member (unless that member explicitly wishes to not participate in the project) with an identifiable contribution to the paper (either by providing scientific input, developing code or providing support).
All NuGrid collaborators are welcome to participate to projects listed in the folder applications, if interested to contribute.
All active collaborators will have access to the subversion repository that include the most advanced version of the NuGrid codes (including the ppn family post-processing codes, plotting packages). Versions developed for specific applications will also be available in individual branches (to ensure that all past results can be reproduced). Collaborators also have full access to the NuGrid library (both published and unpublished) to use for research projects.
NuGrid proposals are proposals of NuGrid collaborators where NuGrid data or tools are going to be used. Proposals have many constraints and limitations and our aim here is to be flexible. What we do want is to ensure full communication on all such NuGrid proposals.
In proposals involving NuGrid collaborators using NuGrid tools, the proposal should be, time permitting, discussed during a teleconference and a brief description should be added to the application folder, allowing active participation in the NuGrid team. In rush cases, as many proposals are, NuGrid collaborators may send an e-mail to the NuGrid collaboration list.
For participant proposals, we request the participant to send the NuGrid team (through their collaborator contact) this same information. Especially if the participant requires new models/tools, these requests should be sent to the NuGrid team before the submission of the proposal.
As NuGrid projects are completed and results are published, we will make all associated data publicly available—if you make use of this public data, please also respect the associated citation and acknowledgment requests.
For our own record-keeping, please also let us know if you submit a proposal that includes planned use of public NuGrid products or collaboration with NuGrid.