General and Shared Risk Observing
VLA, VLBA, and GBT observing are classified into two categories: General Observing (GO) and Shared Risk Observing (SRO). The GO category includes the standard capabilities of VLA, VLBA, or GBT whereas the SRO program accommodates those who seek to utilize the facilities beyond their regular capacities. The Call for Proposals provides a detailed outline of what constitutes these categories for each facility.
The Observatory expects that most SRO programs will have no or only minor problems that can be corrected quickly. If an SRO program fails, however, and it becomes clear that detailed testing with additional expertise is needed, then the project must make an experienced member from their team available to help troubleshoot the problem. In some cases, this may require the presence of that experienced member. If adequate support from the project is not given, then the time on the telescope still will be forfeited. The additional effort is to be determined based on discussions with the Observatory staff and management and the project team.
VLA or VLBA SRO proposals will not be carried over if they cannot be scheduled for reasons associated with the shared risk component(s) of the observations, even if awarded priority A. VLA or VLBA RSRO proposals will not be awarded priority A, but would be subject to the same conditions on carry-over as SRO proposals. Those projects in the VLA or VLBA Shared Risk and Resident Shared Risk categories may not be re-observed if they fail due to problems with the shared risk/resident shared risk component(s) of the observation. If observers believe that an observation should be failed after inspecting their data they should submit a ticket to the NRAO Science Helpdesk as soon as possible and in all cases prior to the expiry of the period of eligibility for scheduling.
For GBT SRO, the proposing team may be asked to provide a "backup" receiver if the original one is not available. In such cases, the observation may proceed with the backup receiver, as long as the observation is not considered a duplicate observation, as defined in Section 7.3.
