1. Telescope Access Metrics Presentation to Program Review Panel September 16, 2004

2. Ground rules Categorize telescopes as –Large: 6.5m or greater Gemini, others with TSIP (FIP) access –Medium: 3-4.2m Mayall, Blanco, WIYN, SOAR –Small: 0.9-2.1m KP 2.1m, WIYN 0.9m, SMARTS Count nights available for science for past semesters Extrapolate for future semesters –Gemini ramps up to 60 U.S. nights/telescope/semester Currently averages ~50 –SOAR begins science observations in 2005B and ramps up over 1 year

3. Precommitments-Surveys Surveys –Note that surveys are subject to the same peer review as regular proposals –20% cap –Proposals only taken once per year –Program started in 1999; none solicited in 2003 or 2004 –Surveys can run up to 5 years –Actual nights committed run 10-20% for both medium and small telescopes –No surveys have been granted on large telescopes

4. Precommitments - NASA Agreements with HST, Chandra, Spitzer Up to 5% of NOAO time available for complementary (not follow-up) ground-based observations connected with successful proposals Proposals go through NASA peer review and NOAO technical review Actual nights committed typically are 5-15 per semester on all telescopes << 15% maximum

5. Precommitments – instrument partnerships Aimed at providing new instrumental capabilities on NOAO telescopes for guaranteed time –U Maryland agreement: 20% of Mayall time Exchangable for WIYN or 2.1m U. Md contribution (cash plus manpower) for NEWFIRM –Flamingos: base (4m: 3n, 2.1m: 5n) plus 4-6n for every 14 nights (after first 14) allocated to community –GSFC IRMOS: draft MOU – 4-5 n per semester on 4m, 8-10 n per semester on 2.1m, –Ge Exoplanet Tracker: draft MOU – 21 n per semester on 2.1m All “guaranteed time proposals” go through TAC –If they do not succeed (which is rare), they are deferred to a later semester so the proposal can be improved

6. Current tally 200220032004200520062007 Large-total Precommit remaining 146 0 146 201 0 201 253 0 253 265 0 265 263 0 263 278 0 278 Medium-total Precommit remaining 739 207 532 698 166 532 654 168 486 714 132 582 774 47 727 786 0 786 Small-total Precommit remaining 1071 186 885 633 141 492 653 119 534 640 29 611 640 12 628 640 0 640

7. Reasonable predictions TSIP will continue to add 25-30 large telescope- nights per year TSIP will also add 30-60 medium telescope-nights per year The survey program will resume in 2005, leading to a future level of precommitment about the same as the past The NASA precommitments will continue at a level of a few nights per semester PREST will add approximately 200 nights of small telescope time per year

8. Tally with reasonable predictions 200220032004200520062007 Large-total Precommit remaining 146 0 146 201 0 201 253 0 253 277 0 277 290 0 290 305 0 305 Medium-total Precommit remaining 739 207 532 698 166 532 654 168 486 744 170 574 834 170 664 846 170 676 Small-total Precommit remaining 1071 186 885 633 141 492 653 119 534 690 140 550 740 140 600 840 140 700

9. Nights remaining with predictions

10. Oversubscription rates Nights requested divided by nights available after precommitment Even with devolution of small telescopes, access is reasonable Survey proposals (not included in graph) run 4.5- 5.5 for medium telescopes; 1.5-2.5 for small telescopes

11. Conclusions All oversubscription rates are in healthy range – and increase with increasing aperture Status quo results in reasonable access TSIP and PREST are expected to improve the situation – particularly for medium and small telescopes –Large telescope access is limited by willingness of independent observatories to give up more nights (TSIP) and by our fraction of Gemini.