Policy and Procedure

The Policy

HEPData is an open-access repository for scattering data from experimental particle physics. It stores and provides access to data points from several thousand publications produced by multiple Collaborations working in High Energy and Nuclear Physics, and is hosted by CERN as a part of its Open Data initiative. It is a durable and well-supported platform. The PHENIX Collaboration is using HEPData as one of the principal components of its Data and Analysis Preservation (DAP) effort and manages a growing collection of HEPData entries. Each entry is a specially formatted data package representing numerical data used in figures and tables in a particular publication. The HEPData portal has the functionality to produce nicely formatted web pages complete with data tabulation, plot visualization etc. Only publications which are indexed on the InspireHEP portal are eligible for this process.

By the policy established by the PHENIX IB, every paper containing tables and/or plots must be accompanied by a HEPData-compliant data package containing the tables and/or plots data before it is approved for publication. Please see the official policy document (sec. IV.iv):


“The IRC shall be empowered to adjudicate disagreements on the details of the paper. A near-consensus shall be a pre-requisite for the submission of the paper to the preprint arXiv and journal, but only after the IRC has certified that data tables are available in proper format for later submission to HEP data.”

Detailed information for preparing and uploading HEPData materials can be found on the HEPData instructions page.


Each collaboration using the HEPData portal has a coordinator registered on that Web resource. That person is reponsible for managing the submission workflow, such as initiating the submission and communicating with PPG and IRC, as well as handling exceptional situations such as modifications of the already published HEPData entries. At the time of writing, PHENIX has delegated this responsibility to M.Potekhin (potekhin_at_bnl_dot_gov).

Outline of the Procedure

It is assumed that the PPG members responsible for the HEPData submission have GitHub accounts and basic GitHub proficiency since the workflow involves a dedicated PHENIX repository. Please take a look at the repository if you are new to this activity, as materials posted there are well designed working examples. The procedure of publishing materials on HEPData includes the following principal elements:

  1. Preparing a properly formatted data package and making use of GitHub to manage prepared materials (e.g. to review, test and correct materials if necessary).
  2. Designating an uploader - member of the PPG. This person will perform the file upload and be reponsible to making additions and corrections if necessary.
  3. Designating a reviewer - member of the IRC. This person will review the submitted material and will either approve it, or direct corrections requests to the uploader.
  4. Notifying the HEPData Coordinator so that the process can be initiated, followed up and finalized after the review.

The central part of the publishing process is the review of the submission package. This involves communication between the reviewer and the uploader (for example, a request to fix some erroneous data or a typo). The optimal way to do it is by using a messaging system built into the HEPData portal and accessible directly from the web page created for each submission. There is a discussion panel allocated to each table/plot so communication can be focused and unambiguous. Since using this functionality is highly desirable, it is expected that both the uploader and the reviewer have regular accounts on the HEPData portal. If this is not already the case, getting registered is straightforward. The e-mail addresses used for registration need to be communicated to the PHENIX HEPData coordinator (see above) to properly initiate the submission process. Optionally, this information may be included as ‘#’ comments into the submission.yaml file (see the instructions).

The following diagram illustrates the flow of communication among the three principal participants of the HEPData process: the coordinator, the uploader and the reviewer.

As noted above, it is optimal for the uploader and the reviewer to make use of the messaging mechanism on the HEPData portal. A submission typically contains multiple items i.e. data from multiple plots. Each item is reviewed and approved separately. If corrections are needed, the uploader edits requisite data and checks it into the repository. Please don’t hesitate to contact the HEPData coordinator if you have questions. Detailed instructions for the submission process are available on a dedicated page.