Current and Future Science with NRAO Instruments

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Current and Future Science with NRAO Instruments
National Radio Astronomy Observatory
NRAO Operations Review February 29 March 1,
2008

• Chris Carilli

• 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!

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• Radio studies of the first galaxies gas, dust,
  star formation, into cosmic reionization

Dark Ages

• Major science driver for all future large area
  telescopes
• Last phase of cosmic evolution to be tested
• Bench-mark in cosmic structure formation
  indicating the first luminous sources

Cosmic Reionization
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Pushing into reionization QSO 114852 at z6.4
(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.)

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mm/cm Gas, Dust, Star Form, in host galaxy of
J11485251
CO3-2 VLA z6.42
MAMBO/IRAM 30m
LFIR 1.2e13 Lo
1 6kpc

• 30 of zgt6 SDSS QSO hosts are HyLIRGs
• Dust formation? AGB Winds take gt 1.4e9yr gt age
  Universe
• gt dust formation associated with high mass star
  formation?

• Dust mass 7e8 Mo
• Gas mass 2e10 Mo
• CO size 6 kpc
• Note low order molecular lines redshift to cm
  bands

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Continuum SED and CO excitation ISM physics at
z6.42
Elvis QSO SED
50K
NGC253
Radio-FIR correlation
MW

• FIR excess -- follows Radio-FIR correlation
  SFR 3000 Mo/yr
• CO excitation starburst nucleus Tkin 100K,
  nH2 1e5 cm-3

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CII 158um at z6.4 dominant ISM gas coolant
IRAM 30m

• zgt4 gt FS lines redshift to mm band
• LCII 4x109 Lo (LNII lt 0.1 LCII)
• CII similar extension as molecular gas 6kpc
  gt distributed star formation
• SFR 6.5e-6 LCII 3000 Mo/yr

CII
NII
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CII PdBI Walter et al.
CII CO 3-2
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Building a giant elliptical galaxy SMBH at
tuniv lt 1Gyr
z10
10.5

• Multi-scale simulation isolating most massive
  halo in 3 Gpc3 (co-mov)
• Stellar mass 1e12 Mo forms in series (7) of
  major, gas rich mergers from z14, 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 z0

Li, Hernquist, Roberston..
8.1
6.5

• Rapid enrichment of metals, dust, molecules
• Rare, extreme mass objects 100 SDSS z6 QSOs
  on entire sky
• Integration times of hours to days to detect
  HyLIGRs

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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.
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Pushing to normal galaxies continuum A
Panchromatic view of galaxy formation
Arp 220 vs z
SMA
cm Star formation, AGN
(sub)mm Dust, cool gas
Near-IR Stars, ionized gas, AGN
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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!
with Ho constraint
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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??
Herrnstein et al. (1999)

• Recalibrate Cepheid distance scale
• Problem NGC 4258 is too close

D 7.2 ? 0.5 Mpc
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• 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
  (VLBAGBTEffeVLA) 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
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UGC 3789 A Maser Disk in the Hubble Flow
Acceleration modeling
D 51 Mpc Ho 64 (/-7)
Already at HST Key project accuracy with 1 source!
Discovery Braatz Gugliucci
(2008) VLBI imaging Reid et al. (in
prep) Distance/modeling Braatz et al. (in prep)
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III. Protoplanetary disks and planet formation

• SMA 350 GHz detection of proplyds in Orion
• Derive dust mass (gt0.01Mo), temperature

HST
Williams et al.
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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 gt disk gap caused by large
  planet formation at 4AU?

Calvet et al. 2002
mid-IR gap
cm slope pebbles
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TW Hya Disk VLA observations of planet formation

• VLA imaging on AU-scales
• consistent with disk gap model
• cm probes grains sizes between ISM dust and
  planetesimals (1cm)

Dec -34
Hughes, Wilner
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Birth of planets The ALMA/EVLA revolution
ALMA 850 GHz, 20mas res. Wolfe
Radius 5AU 0.1 at 50pc Mass ratio 0.5MJup
/1.0 Msun
Wilner

• 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 10s mas
• Herschel dust spectroscopy

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TW Hya -- Molecular gas SMA Gas mass,
rotation ALMA dynamics at sub-AU, sub-km/s
resolution
SMA
ALMA simulation Wilner
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• IV. At the extremes of physics
• Extreme gravity using pulsars to detect nHz
  gravity waves
• TeV sources explained by VLBI!

Credit Bill Saxton, NRAO
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Gravitational Wave Detection using a pulsar
timing array with NANOGrav (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
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NanoGrav
Credit D. Manchester, G. Hobbs
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LS I 61 303 Solving the TeV mystery
Harrison 2000
Xray

• Discovered 1976 _at_ 100 MeV variable 5 GHz
  emission.
• High mass binary 12 M? Be , 13M? NS or
  BH.
• Eccentric orbit e0.7, period 26.5 days.
  
• X-rays peak _at_ periastron, radio 0.5 cycle
  later.
• TeV detected by Magic
• MODELS
• Accretion powered relativistic jet
  (microQuasar?)
• Compact pulsar wind nebula

Radio
gt 400 GeV
Albert 2006
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VLBA Images vs. Orbital Phase(orbit
exaggerated)
VLBA resolution 2AU
Dhawan
Be
VLBA movie shows 'cometary' morphology gt a
Pulsar Wind Nebula shaped by the Be star
envi-ronment, not a relativistic jet.
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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.
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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 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 -- Mankinds highest resolution instrument

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END
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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
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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