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National Radio Astronomy Observatory – Town HallAAS 211th Meeting – Austin, Texas
Science Synergies with NRAO Telescopes
Chris Carill
NRAO
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z >6 => Low order molecular transitions redshift to the short cm bands•LBH = 1e14 Lo
•Black hole mass ~3 x 109 Mo
•Gas mass ~ 2e10 Mo
•Dust mass ~ 7e8 Mo
•Dyn. Mass ~ 2e10/(sin)^2 Mo
First light: Pushing into Cosmic Reionization (tuniv < 1Gyr)
SDSS J1148+5251 z=6.42
1” ~ 5.5kpc
CO3-2 VLA
GP absorption => Universe is opaque at obs < 0.9um
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FIR excess in 30% of z~6 QSO host galaxies: LFIR ~ 1e13 Lo
Follows Radio-FIR correlation: SFR ~ 3000 Mo/yr
CO excitation ~ starburst nucleus: Tkin ~ 100K, nH2 ~ 1e5 cm^-3
Radio-FIR correlation
50KElvis QSO SED
Continuum SED and CO excitation ladder
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[CII] 158um ISM gas cooling line at z=6.4 30m 256GHz
Maiolino etal
CII PdBI Walter et al.
FS lines redshift to mm wavelengths at z>6
Structure identical to CO 3-2” (~ 6 kpc) => distributed gas heating = star formation?
SFR ~ 6.5e-6 L[CII] ~ 3000 Mo/yr
=> coeval formation of giant elliptical galaxy + SMBH within 870 Myr of Big Bang
1”
CII + CO 3-2
Prediction: Fine structure lines will be the work-horse lines for studies of the first galaxies with ALMA.
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J0840
GBT CO2-1 PdBI CO5-4
Sub-thermal excitation of CO 5-4
=> Super-massive molecular gas reservoir = 9e10Mo, of cooler (<40K), lower density (<1e4cm^-3), molecular gas
Cold gas at high redshift: QSO host galaxy at z=5.85
Wagg, Wang, et al. 2008
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Median stacking of 6500 U-dropouts (z~3) from Cosmos field
• SFR(radio) = 73 Mo/yr
• SFR(UV) = 14 Mo/yr (w/o dust correction)
UV dust attenuation factor for LBGs = 5.2 +/- 1.2
EVLA will detect synchrotron from individual LBGs in ~ 10hr with FoV ~ 30arcmin
ALMA will detect dust, CO in ~ 1 hr (although smaller FoV ~ 20arcsec)
VLA 1.4GHz
S1.4 = 0.9 +/- 0.21 uJy
See poster by N. Lee
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(sub)mm: high order molecular lines + fine structure lines: ISM physics and star formation
cm telescopes: low order molecular transitions: total gas mass, dense gas tracers, dynamics
Synergy: spectral line studies of normal galaxies into reionization
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cm: Star formation, AGN
(sub)mm Dust, molecular gas
Near-IR: Stars, ionized gas, AGN
Arp 220 vs z
Synergy: continuum
A Panchromatic view of galaxy formation
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NRAO: One Observatory serving all astronomers
Time allocation
• Single proposal tool, serving all NRAO telescopes
• Joint programs: single proposal using multiple telescopes, as dictated by science goals
• Panel review(s?) with broad range of representation
NRAO Archive: ‘one stop shopping’
• Single archive with raw data and standard data products: pipeline processed images, spectra
• Single interface
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NRAO and the community: moving together into the 21st Century
Example: ALMA development budget
• $10M/year (globally) => leverage $1.2G investment to remain state-of-art for 20+ years
• Hardware and software projects can be proposed and carried out by the NRAO, other institutions within North America, or as collaborative efforts.
ALMA Board resolution: “The ALMA Board has charged the project to develop a long term ALMA Development Plan in consultation with the international astronomy community. The plan should set out the scientific context for transformational science with ALMA in 2020, in the era of, for example, JWST, ELTs and SKA, and the developments necessary to achieve this vision. The ALMA Board views this plan as having the utmost strategic priority, and is coordinating its development across the entire ALMA partnership.”
Guiding principle: This should be a pan-chromatic perspective, incorporating ALMA's appeal to non-sub-mm/mm specialists
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The Process
Stage I
• The JAO Project Scientist and the ASAC identify the scientific themes for sub-groups (for example: star formation, galaxy formation,…), with input from regional science advisory committees (ANASAC in NA)
• International ALMA Workshop organized by JAO, with broad community involvement, following the sub-group theme
• Sub-group Chairs, the ASAC and JAO produce the preliminary report
Stage II
• Preliminary report distributed to Executives and used for any necessary regional activities, coordinated by ANASAC in NA
• Presented in appropriate forums in each region for further feedback, eg. ANASAC meetings, NAASC workshops, AAS townhall(s)
• Sub-group Chairs, the ASAC and JAO produce the final report based on feedback
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END