TAC issues

Letizia StanghelliniNOAO

16 June 2008 – Science with Giant Telescopes

The NOAO TAC– The NOAO TAC system deals with the community access to:•The national observatories (KPNO, CTIO)•Gemini (international partnership)•Public and private partnership observatories

– NOAO + university partners (e.g., WIYN, SOAR)– NOAO public time on Keck, Magellan, MMT, HET via TSIP

– NOAO TAC science-based; observers request selection of telescopes/instruments offered, based on their science needs

– TAC Members chosen from the community at large, based on scientific excellence

TAC models – Single observatory

•International partners– ESO (one OPC, national partners shares expected to be fulfilled- members selected from member counties)

– Gemini (national TACs, ITAC to oversee queue/shares/ToO )

•Multi-partners– Keck, Magellan, WIYN (member TACs, no super-TAC, no general ToO policy except for public access)

TAC models – ground based obs.

• Partner TACs plus observatory TAC (i.e., super-TAC)– Oversight of science policies, control over science time especially ToO

– Lesser partners are disadvantaged (especially if queue modes are used, since availability of specific weather conditions is limited)

• Pre-determined shares and partner TACs– Limited scientific oversight– Partners more likely to get their fair share

Proposal pressure

Distribution of the size of scheduled programs

Telescope aperture < 6m (KP, CT, WIYN, SOAR)

Telescope aperture > 6m(GEM and TSIP)

Note the evolution toward smaller programs

Scheduled programs by team size

Over time, the number of large(>5 people) teams is almost invariant for proposals requestingsmall apertures, while it increases for those requesting large apertures

Joint NASA/NOAO programs