VLBA Key Science: Making It Happen

1. VLBA Key Science: Making It Happen • Bob Dickman • AD for New Mexico Operations

2. Partnerships & Evolution of VLBA Operating Models • NSF Senior Review recommended that: • NRAO seek external funding for VLBA operations • The instrument be closed if 50% of the direct cost of operations (~ $3M) was not raised by FY 2011 • Indications are currently positive for partnerships with NASA, USNO: • NASA: 33 GHz QSO reference frame + interplanetary spacecraft navigation (see Vivek Dhawan’s poster paper) • USNO: Earth rotation measurements • A draft interagency agreement between NSF, NASA, USNO is under active review; aiming to finalize and sign the agreement by FY2010 • The pending partnership agreements means the VLBA will remain open for scientific observing till at least FY2015 • Long term future depends on science impact of VLBA/VLBI! NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY 2

3. The VLBA Operational Model Will Evolve The partnerships will require guaranteed access to the instrument: Generally scheduled observations; ~ 1600 hours per year High priority, preemptively allocated time slots (e.g., mission-critical observations) Reduction in open science time will be mitigated by additional recording media A much larger fraction of VLBA open time will likely be allocated to Key Projects, if worthwhile projects are proposed Many key projects may depend on the VLBA sensitivity upgrade program They may be large projects NRAO will emphasize getting the key projects “done right,” and will support these projects NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY 3

4. Key Science Projects • “Key Science Project” status will be assigned to projects by the Proposal Selection Committee (PSC). These will represent projects with high referee ranking and high science impact • NRAO will endeavor to provide the maximum support to Key Projects projects as much as possible • “Key Science Projects” may include both regular and large projects. • There will be no a priori limit to the amount of time that can be assigned to Key Science Projects. • Note that the Users Committee urged that the amount of time allocated to large projects be up to 50% of the time at any particular LST during any trimester • In the end, the limit should be science driven NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY

5. VLBA Key Science Policy (I) • Large Key Science Projects will be encouraged to send students or postdocs to be in residence at NRAO-Socorro • NRAO staff will assist with training these individuals in VLBI techniques • Residents will be expected to assist with data quality assurance • Users are reminded of the VLBA student support program for funding VLBA-related research by students at US universities and colleges: • http://wiki.gb.nrao.edu/bin/view/Observing/NRAOStudentSupportProgram • We expect that NRAO will be able to support 2 Gbps sustained data rates for Key Science Projects by end of 2010 NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY

6. VLBA Key Science Policy (II) • Requests for higher data rates will be considered and reviewed by the PSC: • Requests will be granted based on the availability of media and correlator capacity, and will be prioritized according to scientific merit • PIs may wish to contact NRAO staff ahead of time for help in determining the media requirements for a particular project • If a request for higher data rates is not accepted due to a lack of available recording media or correlator time, PIs may provide additional media and/or associated correlator capacity • Any additional hardware provided should become part of the generally-available VLBA media pool and/or integrated into the correlator cluster NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY

7. Questions? NEW SCIENCE ENABLED BY MICROARCSECOND ASTROMETRY