1

NRAO Socorro Science RetreatSocorro, NM, April 10, 2008

Science imperatives for 2020Chris Carilli

NRAO

• I will not define the science imperatives for NRAO in the next decade.

• I will present current landscape: science cases in radio, optical…, plus various committee reports.

• Goal: Science-driven vision for (radio) astronomy in next decade. Where does NRAO fit? How do we approach DS2010?

2

Documents considered• Historical perspective -- pre-2020 review

Reports: Decadal Survey (McKee/Taylor), Quarks-Cosmos

Science goals: EVLA, ALMA

• Intermezzo: Major advances in astrophysics since DS2000/EVLA

• Modern era -- post-2020 review

Science goals: SKA, JWST, TMT, LSST, Herschel, ConX

Reports: RMSPG, AUI-Futures (McCray), Chicago I,II,III

Science cases can be:

• Facility based/Technology driven

• Theme based

• Question based

• Project/experiment based

3

Historical perspective

DS2000 (McKee-Taylor) Facility based

• Broad-brush document -- too much so, unrealistic costing?

• EVLA, ALMA recommended highly

• Recommended both User grants and development $$

Quarks-to-Cosmos -- supplanted DS2000? Question based

•What is dark matter? (HI studies)

•What is dark energy? (HI surveys)

•How did Universe begin? (CMB)

•Did Einstein have last word on gravity? (Pulsars)

•Neutrino mass and evolution?

• Cosmic accelerators? (AGN/SNR)

•Are protons stable?

•New states of matter at high den/temp? (Neutron stars)

•Are there extra dimensions?

•How are elements Fe -- U formed?

•Is new theory of matter/light needed at highest energies?

4

EVLA science case

Science theme based

• The Magnetic Universe -- obvious radio forte

• The Obscured Universe -- PPdisks, YSOs, QSO abs lines…

• The Transient Universe -- GRBs, XRBs, Mdwarfs…

• The Evolving Universe -- galaxy evolution

Question: was the science case generated before or after the technical case?

5

ALMA science: Project based

• Image molecular gas in z~3 MW-mass galaxies => A/T (64x12m)

• Image PP disks on AU scales => ~10km baselines @ submm

• HST quality imaging => # ant, ACA + TP

Actively involved/energized User community

• Continuous refinement of ALMA science case, enabled by, but not dictated by, executives

• ASAC + regional SACs: eg. organized the DRSP = observing proposals for ALMA from community to gauge ‘demand’ and prioritize use cases

• Annual regional topical science meetings

• Regular international ‘love fests’

6

Advances in modern astrophysics since DS00 and EVLA

• Precision cosmology: few % knowledge of age, mass-energy content of Universe

• Probing epoch of first light (cosmic reionization) at z >~ 6

• GRBs = biggest explosions in Universe, massive star explosions to z ~ 6

• MBH - Mbulge => all spheroids have BHs with fixed mass ratio. BH and Galaxy evolution are causally connected

• Quasars ~ AGN on 1e7 smaller scales

• double pulsars + Glob Cluster pulsars, gravity waves -- unprecedented labs for tests strong field GR

• Extrasolar planets -- they are everywhere!

• Proto-planetary disks: clear signatures of planet formation

• Kuiper-belt objects -- what is Pluto?

• Mapping Universe -- SDSS, FIRST, NVSS, COSMOS, UDF, …

7

• Three year process run by ISAC

• Experiment based: Quantified ‘experiments’ for future large area cm telescopes – not just radio astronomy reviews nor root N science

• 50 chapters, 90 contributing authors, 25% theorists, but minority of multiwavelength observers

8

Cradle of Life: protoplanetary disks on (sub)AU scales + astrobiology + SETI

Cosmic reionization and first light: IGM evolution through HI 21cm line + gas/dust/SF/AGN in first galaxies

Dark energy and galaxy evolution: All sky HI (+ continuum) survey

Strong field tests of GR using pulsars

Origin and evolution of cosmic magnetism: all sky RM survey

Key Science Projects: (i) Address key questions, (ii) Unique role of radio, or complementary but critical, (iii) Excites broad community

9

• All require sensitivity: A/T >= 1e4 m^2/K

• Most require frequencies >= 10 GHz

• Many require > 1deg^2 FoV at 1.4 GHz

• Some require > 1000 km baselines

• Some require multibeaming

Downside -- still too broad to be practical for one facility

10

SKA path-finders (spurred, in part, by SKA science discussions)

HI 21cm survey instruments

• ASKAP (Oz) -- $100M

• MeerKAT (SA) -- $100M

• PrepSKA (EU) -- $50M

• Apertif (WSRT FPA) -- $10M

Reionization experiments

LOFAR -- $100M

MWA -- $10M

PAPER -- $2M

11

SKA phased approach

• Phase I: SKA mid, 0.5 to 3 (or 10?) GHz, 10% collecting area, some long baselines, tile arrays + small dishes, large FoV

• Phase II: Full SKA mid, plus full SKA low (70 -- 200MHz)

• Phase III: up to 25GHz -- not specified as to how, or when, to get there (and why 25GHz vs. 45GHz?)

Phase I Phase II

12

Optical/near-IR Telescope Science Priorities

Thirty meter telescope: Science themes, mostly spectra

•Spectroscopic exploration of First Light and reionization -- Pop III stars and first galaxies

•Exploration of galaxies and LSS in young Universe: spectroscopy of galaxy assembly

•Investigation of massive black holes throughout cosmic time: coeval formation gal/BH

•Exploration of planet formation processes and the characterization of extrasolar planets

13

Optical/near-IR Telescope Science Priorities

JWST: science themes, mostly near-IR imaging + spectra

• First light and cosmic reionization

• Assembly of galaxies and black holes

• Birth of stars and proto-planetary systems: dusty disks in near-IR

• Planets and the origins of life: imaging extrasolar giant planets + KPOs…

14

LSST: Project based

• Constraining dark energy and dark matter: very large volume survey

• Taking an inventory of the solar system

• Exploring the transient optical sky

• Mapping the Milky Way

Optical/near-IR Telescope Science Priorities

15

Herschel: Science theme based

•How galaxies formed and evolved in the early universe, and the nature of enormously powerful galactic energy sources.

•The formation, evolution, and interrelationship of stars and the interstellar medium in the Milky Way and other galaxies.

•Chemistry in our galaxy.

•Molecular chemistry in the atmospheres of Mars and our solar system's comets and giant planets, and the nature of comet-like objects in the Kuiper belt beyond Neptune.

FIR Space Telescopes

16

Constellation X: Experiment based

• Black Holes: Using black holes to test General Relativity (GR) and measuring black hole spin

• Dark Energy: Improving the constraints on the key Dark Energy (DE) parameters by a factor of ten

• Missing Baryons: Unambiguous detection of the hot phase of the Warm-Hot Intergalactic Medium (WHIM) at z>0

• Neutron Star Equation of State: Measuring the mass-radius relation of neutron stars to determine the Equation of State (EOS) of ultra-dense matter

Xray Telescopes

17

Common ground and radio contributions

Galaxy/Black hole evolution

SKA, (ALMA), TMT, JWST, Herschel

gas, dust, star form, dynamics, BHs

First light and reionization

SKA, (ALMA), TMT, JWST

IGM (21cm), gas, dust, star form, dyn, BHs

Planets and proto-planetary disks

SKA, (ALMA), TMT, JWST

Sub-AU imaging

Dark energy SKA, LSST, ConX Very wide field survey

Star formation (ALMA), JWST, Herschel

gas, dust

Testing GR SKA, ConX, (LIGO) pulsars

Theme Telescopes Radio role

18

Other Radio DiscussionsRMSPG: Haynes et al. Facility approach

• Written as radio input to senior review

• Excellent summary of existing facilities

Chicago I, II, III: NRAO/AUI/NAIC coordinated effort to consider scientific future of radio astronomy, in preparation for DS2010

• Engage broader community -- optical, theory, high energy (not connected to SKA)

• No clear consensus on science, although some support for HI surveys

Working groups established: produce WP for DS2010

• SKA low (Beasley chair)

• SKA mid (Lazio/Myers) -- RSST

• SKA high -- no current WG?

19

AUI Futures of Radio Astronomy Committee: Chair D. McCray

Science theme approach:

•Beyond standard model of physics and cosmology

•Origin/evol galaxies

•Origin/evol stars/planets/life

•The high energy Universe

•Fundamental and extreme physics

Current recommendations (likely to be much revised):

•Maintain a balanced and vigorous program in RMS science and technology development

•Develop, test, prototype and implement technologies leading to SKA-class facilities

•Nurture partnerships leading to SKA-class facilities

20

McCray Summary at Jan08 AAS

• Ensure proper operation of ALMA, EVLA, GBT: ease of use for non-experts, grants => leverage capital investment

• Maintain technical development and educational aspects at (some) UROs.

• Emphasize surveys -- FPAs, wide field imaging.

• SKA -- stay the course of TDP, not ready for $100M investment.

• No specific statement on VLBA or Arecibo.

21

Closing ruminationsALMA

• Development plan ($10M/yr): science working groups and implementation opportunities provides natural forum for continued advancement of science case and instrument

• Should NRAO secure access to supporting facilities (LMT, CCAT…)?

EVLA: re-energize the community (and staff!), led by SAGE

• Regenerate science case in modern context: phase I, II, III (?)

• and/or DRSP for EVLA

• EVLA science meeting(s)

• Needed if want any chance of getting proper User support $$

• Might present path forward for DS2010

22

Closing ruminations

VLBA: active staff participation in upgrade planning

GBT: clear near-term priorities for instrument development

SKA and DS2010

NRAO/AUI has conducted three major forums to determine the way forward for DS2010: Chicago meetings, AUI Futures Committee, Strategic planning retreats

Thus far, no clear consensus has been reached in any forum.

23

END