Current and Future Science with NRAO Instruments

1. National Radio Astronomy Observatory NRAO Operations Review ~ February 29 – March 1, 2008 Current and Future Science with NRAO Instruments Chris Carilli Current large programs: snapshot of major scientific use of NRAO telescopes. Four exemplary science programs that demonstrate the synergy between NRAO instruments, and their key roles in modern, multiwavelength astrophysics. First galaxies: gas, dust, star formation into cosmic reionization Cosmic geometry: Megamasers and a 3% measure of Ho Protoplanetary disks: imaging planet formation At the extremes of physics: strong field GR, TeV sources explained!

2. Current large programs: VLA, VLBA, GBT • Radio interferometric planet search -- VLBA, VLA, GBT • Coordinated radio and infrared survey for high mass star formation -- VLA • Definitive test of star formation theory -- GBT • Legacy survey of prebiotic molecules toward Sgr B2 and TMC-1 -- GBT • Detecting nHz gravitational radiation using pulsar timing array -- GBT • Star Formation History and ISM Feedback in Nearby Galaxies -- VLA • LITTLE THINGS survey: HI in dwarf galaxies -- VLA • Megamaser cosmology project -- GBT, VLBA, VLA • Probing blazars through multi-waveband variability of flux, polarization, and structure -- VLBA • MOJAVE/GLAST program: mas imaging of gamma ray sources -- VLBA • VLA low frequency sky survey -- VLA • Deep 1.4 GHz observations of extended CDFS -- VLA AUI Operations Review February 29 – March 1, 2008

3. Radio studies of the first galaxies: gas, dust, star formation, into cosmic reionization Dark Ages • Last phase of cosmic evolution to be tested • Bench-mark in cosmic structure formation indicating the first luminous sources • Major science driver for all future large area telescopes Cosmic Reionization

4. Pushing into reionization: QSO 1148+52 at z=6.4 (tuniv = 0.87Gyr) • Highest redshift SDSS QSO • Lbol = 1e14 Lo • Black hole: ~3 x 109 Mo (Willot etal.) • Gunn Peterson trough = near edge of reionization (Fan etal.)

5. mm/cm: Gas, Dust, Star Form, in host galaxy of J1148+5251 CO3-2 VLA z=6.42 MAMBO/IRAM 30m LFIR = 1.2e13 Lo 1” ~ 6kpc Dust formation? AGB Winds take > 1.4e9yr > age Universe => dust formation associated with high mass star formation (Maiolino+ 07, Dwek+ 2007, Shull+ 2007)? • Dust mass ~ 7e8 Mo • Gas mass ~ 2e10 Mo • CO size ~ 6 kpc • Note: low order molecular lines redshift to cm bands

6. Continuum SED and CO excitation: ISM physics at z=6.42 Elvis QSO SED 50K Radio-FIR correlation NGC253 • FIR excess -- follows Radio-FIR correlation: SFR ~ 3000 Mo/yr • CO excitation ~ starburst nucleus: Tkin ~ 100K, nH2 ~ 1e5 cm^-3

7. [CII] 158um at z=6.4: dominant ISM gas coolant IRAM 30m • z>4 => FS lines redshift to mm band • [CII] traces star formation: similar extension as molecular gas ~ 6kpc • L[CII] = 4x109 Lo (L[NII] < 0.1 L[CII]) • SFR ~ 6.5e-6 L[CII] ~ 3000 Mo/yr [CII] [NII] 1” [CII] PdBI Walter et al. [CII] + CO 3-2

8. Building a giant elliptical galaxy + SMBH at tuniv < 1Gyr z=10 10.5 • Multi-scale simulation isolating most massive halo in 3Gpc^3 (co-mov) • Stellar mass ~ 1e12 Mo forms in series (7) of major, gas rich mergers from z~14, with SFR ~ 1e3 - 1e4 Mo/yr • SMBH of ~ 2e9 Mo forms via Eddington-limited accretion + mergers • Evolves into giant elliptical galaxy in massive cluster (3e15 Mo) by z=0 Li, Hernquist, Roberston.. 8.1 6.5 • Rapid enrichment of metals, dust, molecules • Rare, extreme mass objects: ~ 100 SDSS z~6 QSOs on entire sky • Integration times of hours to days to detect HyLIGRs

9. SMA Pushing to first normal galaxies: spectral lines cm telescopes: low order molecular transitions -- total gas mass, dense gas tracers , GBT (sub)mm: high order molecular lines. fine structure lines -- ISM physics, dynamics • FS lines will be workhorse lines in the study of the first galaxies with ALMA. • Study of molecular gas in first galaxies will be done primarily with cm telescopes ALMA will detect dust, molecular and FS lines in ~ 1 hr in ‘normal’ galaxies (SFR ~ 10 Mo/yr = LBGs, LAEs) at z ~ 6, and derive z directly from mm lines.

10. Pushing to normal galaxies: continuum A Panchromatic view of galaxy formation Arp 220 vs z SMA cm: Star formation, AGN (sub)mm Dust, molecular gas Near-IR: Stars, ionized gas, AGN

11. II. Cosmic geometry: Ho to few % with water maser disks.Why do we need an accurate measure of Ho? To make full use of 1% measures of cosmological parameters via Planck-CMB studies requires 1% measure of Ho -- covariance! Current Ho constraint Current Ho constraint

12. Measuring Distances to H2O Megamasers NGC 4258 Two methods to determine distance: • “Acceleration” method D = Vr2 / a • “Proper motion” method D = Vr / (d/dt)  Vr D = r/ 2Vr 2 a = Vr2/r D = Vr2/a • Recalibrate Cepheid distance scale • Problem: NGC 4258 is too close • Earth baselines => resolution > 0.4 mas => max. distance ~ 120 Mpc Herrnstein et al. (1999) D = 7.2  0.5 Mpc

13. The Project (Braatz et al.) Identify maser disk galaxies with GBT into Hubble flow ~ 50 currently Obtain high-fidelity images of the sub-pc disks with the High Sensitivity Array (VLBA+GBT+Eff+eVLA) ~ 10% are useful Measure internal accelerations with GBT monitoring Model maser disk dynamics and determine distance to host galaxy GBT Goal: 3% measure of Ho

14. UGC 3789: A Maser Disk in the Hubble Flow Acceleration modeling D ~ 51 Mpc Ho= 64 (tentative) Discovery: Braatz & Gugliucci (2008) VLBI imaging: Reid et al. (in prep) Distance/modeling: Braatz et al. (in prep)

15. III. Protoplanetary disks and planet formation • SMA 350 GHz detection of proplyds in Orion • Derive dust mass (>0.01Mo), temperature HST Williams et al.

16. TW Hya Disk: VLA observations of planet formation • Pre-solar nebula analog • 50pc distance • star mass = 0.8Mo • Age = 5 -- 10 Myr • mid IR deficit => disk gap caused by large planet formation at ~ 4AU? Calvet et al. 2002 mid-IR “gap” cm slope ”pebbles” • VLA imaging on AU-scales: • consistent with disk gap model • cm probes grains sizes between ISM dust and planetesimals (~1cm) Dec= -34 Hughes, Wilner +

17. Birth of planets: The ALMA/EVLA revolution ALMA 850 GHz, 20mas res. Wolfe + Wilner Radius = 5AU = 0.1” at 50pc Mass ratio = 0.5MJup /1.0 Msun • ALMA: AU-scale imaging of dust, gas, unhindered by opacity, nor confused by the central star • EVLA: AU-scale imaging of large dust grain emission • JWST: image dust shadow on scales 10’s mas • Herschel: dust spectroscopy

18. IV. At the extremes of physics • Extreme gravity: using pulsars to detect nHz gravity waves and explore strong field GR • TeV sources: explained! Credit: Bill Saxton, NRAO

19. Gravitational Wave Detection using a ‘pulsar timing array’ withNANOGrav (Demorest +) • Need ~20-40 MSPs with ~100 ns timing RMS • bi-weekly, multi-freq obs for 5-10 years • Timing precision depends on • - sensitivity (G/Tsys) (i.e. GBT and Arecibo)‏ • - optimal instrumentation (GUPPI -- wideband pulsar BE) Predicted timing residuals Predicted timing residuals D. Backer

20. NanoGrav Credit: D. Manchester, G. Hobbs

21. GR tests: Timing of the Double Pulsar J0737-3039 • GBT provides the best timing precision for this system • 6 post-Keplerian orbital terms give neutron star masses • strong-field tests of GR to 0.05% accuracy • Measure relativistic spin precession: Obs = 5.11+/- 0.4 deg/yr GR = 5.07 deg/yr Kramer et al., 2006, Science, 314, 97

22. LS I +61 303: Solving the TeV mystery Harrison + 2000 Xray • Discovered 1976 @ 100 MeV; variable 5 GHz emission. • High mass binary: 12 Mסּ Be * , 1–3Mסּ NS or BH. • Eccentric orbit e=0.7, period 26.5 days. • X-rays peak @ periastron, radio 0.5 cycle later. • TeV detected by Magic • MODELS: • Accretion powered relativistic jet (microQuasar?) • Compact pulsar wind nebula Radio > 400 GeV Albert+ 2006

23. VLBA Images vs. Orbital Phase(orbit exaggerated) VLBA resolution ~ 2AU Dhawan + Be VLBA movie shows 'cometary' morphology => a Pulsar Wind Nebula shaped by the Be star envi-ronment, not a relativistic jet.

24. Gamma-Rays from AGN Jets • GLAST launch scheduled for May 2008 • VLBA jet imaging on pc-scales during flares required to understand gamma ray production • Prelaunch survey: VIPS project to image 1100 objects (Taylor et al.) • Planned: 43 GHz + GLAST monitoring of gamma ray blazars Marscher et al.

25. NRAO in the modern context • Golden age of astrophysics: NRAO telescopes play a fundamental role in topical areas of modern astrophysics • Precision cosmology: setting the baseline (Planck ++) • Galaxy evolution and first (new) light: gas, dust, star formation (JWST, TMT) • Birth of stars and planets: dust and gas on AU scales (JWST, Herschel) • Testing basic physics: GR, fundamental constants, … (LIGO, LISA) • Resolving high energy phenomena: aray source primer (GLAST, CONX) • Capabilities into next decade will keep NRAO on the cutting edge • ALMA -- biggest single step ever in ground based astronomy • EVLA -- the premier cm telescope on the planet, and a major step to the SKA • GBT -- just hitting its stride, with pending FPA revolution • VLBA -- Mankind’s highest resolution instrument

26. END

27. Accretion onto compact objects • Now: bright black holes • ADAF, JDAF • Jet outflows & state of accretion disk • EVLA + VLBA • Bondi accretion onto single BH in molecular cloud • NS, WD: role of event horizon, magnetic field, spin • 1e-6 Mdot,Edd at GalCtr (1 Msun) • Ledd for 10Msun at M81 10-4 LE (1 Msun) Radio LE (1 Msun) Fender, Migliari, Gallo, Jonker, et al. (this one: Migliari & Fender 2007) Soft X-ray