Rots et al., Persistent Identifiers1 Associating Persistent Identifiers between Trustworthy Repositories Arnold Rots, Alberto Accomazzi, Günther Eichhorn Harvard-Smithsonian Center for Astrophysics

Rots et al., Persistent Identifiers2 Data and Literature The Astrophysics Data Centers Executive Council (ADEC) developed, at the request of Astrophysics Data System (ADS), a standard that allows published papers to link to the archived datasets presented or used in those papers – and vice versa

Rots et al., Persistent Identifiers3 Dataset Identifiers ADEC established a standard for assigning identifiers to datasets: Unique Provide persistent access to datasets But also: Low buy-in

Rots et al., Persistent Identifiers4 Dataset Identifier Spec URI Part of International Virtual Observatory Alliance’s (IVOA) identifier space: ivo://

Rots et al., Persistent Identifiers5 Dataset Identifier Spec URI Part of International Virtual Observatory Alliance’s (IVOA) identifier space Issued under ADS authority: ivo://ADS/

Rots et al., Persistent Identifiers6 Dataset Identifier Spec URI Part of International Virtual Observatory Alliance’s (IVOA) identifier space Issued under ADS authority Published by a recognized observatory: ivo://ADS/Sa.CXO#

Rots et al., Persistent Identifiers7 Dataset Identifier Spec URI Part of International Virtual Observatory Alliance’s (IVOA) identifier space Issued under ADS authority Published by a recognized observatory Which may add its own designations: ivo://ADS/Sa.CXO#obs/8547

Rots et al., Persistent Identifiers8 Dataset Identifier Requirement Needs to lead the user to the dataset I.e., should translate to a URL that allows the user to retrieve a DIP: It may be an interface, as long as the datasets are marked The DIP may be an image, a tarfile, etc. The URI should be supported in perpetuity, though the URL may change

Rots et al., Persistent Identifiers9 Dataset Identifiers & Version The Dataset Identifier is not required to point to the same data version in perpetuity – that’s left to the repository In the Chandra Data Archive we have some 15,000 distinct datasets of 7,000 unique observations We have yet to receive the first request for a dataset that is not default

Rots et al., Persistent Identifiers10 Dataset Identifiers & TDRs The ADEC/ADS Dataset Identifier also satisfies requirement B2.5 in the OCLC/CRL “Trustworthy Repositories Audit & Certification: Criteria and Checklist” If our data centers were to pursue TRAC certification, they pass B2.5 automatically

Rots et al., Persistent Identifiers11 Datasets and Literature It’s a simple matter of associating Dataset Identifiers with “Bibcodes” Agreement with the AAS journal editors that authors can insert the Dataset Identifiers into manuscripts Identifiers are embedded in the data Harvesting Bibcode-Identifier pairs

Rots et al., Persistent Identifiers12 Further Generalization Bibcode can be generalized to a Dataset Identifier: ivo://ADS/ads#2007AJ… Now the harvesting becomes collecting pairs of Dataset Identifiers This provides a mechanism to associate datasets between repositories, e.g., Great Observatory Joint Observations

Rots et al., Persistent Identifiers13 Summary ADEC Dataset Identifiers: … are easy to implement because of decentralized definition … are successful in linking literature and data (but: burden on authors) … qualify under TRAC B2.6 … allow linking of related observations … enjoy all but guaranteed persistence for data published by NASA data centers