Observing > Prop Eval & Time Alloc > Special VLA Director's Discretionary Time - April 2020

Special VLA Director's Discretionary Time - April 2020

A delay of at least 4 weeks in the C to B VLA reconfiguration (originally scheduled for May 11 - 27, 2020) due to the COVID-19 pandemic, has made available additional observing time in the C configuration. Some of this time can be filled by existing approved programs in the 2020A observing queue (see the observing pressure plot), but more than 100 hours of additional observing time is available, largely during daytime LSTs, for which we encourage Director's Discretionary Time (DDT) proposals. DDT proposals may be submitted at any time, but proposals should be submitted by May 11 to receive full consideration.

DDT proposals must be submitted through the Proposal Submission Tool.  DDT proposals are intended to address targets of opportunity, exploratory time, or other science opportunities that can take advantage of this additional available time in C configuration. Note that for the special circumstances surrounding this particular opportunity, the usual expectation that exploratory proposals only request a few hours has been relaxed. Exploratory proposals, on the order of a few tens of hours, for under-subscribed LSTs in the range 1900 to 0800 (see the observing pressure plot), and that can use frequencies up to 12 GHz are encouraged (since the LSTs available are mostly daytime, high frequency observations are not particularly feasible). We also encourage high-risk/high-reward DDT proposals for this special call.

DDT proposals may also be submitted for the purpose of education and public outreach - for example, to image an iconic source or to support an educational opportunity for students. Such proposals should clearly justify the requirements for the requested time allocation and observing mode, and should describe the anticipated impact of the observation.

The list of active triggered proposals, list of approved DDT proposals, and the Proposal Finder Tool (PFT) should be consulted to determine whether there is an active conflicting proposal.

DDT proposals are reviewed by Observatory scientific staff on the basis of the proposals' scientific merit and technical feasibility. These reviews adhere to Observatory policy regarding non-disclosure and conflicts of interest. If a DDT proposal is declined, a brief justification is provided to the proposing team by the relevant Site Director's office. If a DDT proposal is approved, then the relevant Site Director's office, in consultation with the NRAO Director or his/her designee, will assign a proprietary period for the data based on scientific and programmatic considerations.

If a DDT proposal is approved, the Proposal Finder Tool (PFT) will have access to its authors, title, abstract, and approved hours.  The approved DDT proposals can be listed by using the DDT filter under Type.  Use the Archive Access Tool (AAT) to check if a specific proposal has been observed and to access the data.

N.B., DDT proposals cannot be joint proposals that request external telescope time.  For example, a DDT proposal cannot request HST orbits.  Also, Large proposals (those with a request of 200 hours or more) are not considered for DDT.

For NRAO policy on conflicts between DDT and non-DDT proposals, see here.

Further information about the capabilities available on the VLA, and how to propose, can be found in the VLA Observational Status Summary and the Guide to Proposing for the VLA.