Lunatic fringe: probing the dark ages from the dark side of the MoonC. Carilli (NRAO), Sackler Cosmology Conf, Cambridge, MA, 2008

JuddJackie

Supermassive black hole: • Lbol = 1e14 Lo

• Black hole: ~3 x 109 Mo • Gunn Peterson trough => near edge of reionization

Radio astronomy pushing into reionization: gas, dust, star formation in QSO host galaxies at z>6

1” ~ 6kpc

CO3-2 VLA

S ~ 0.6 mJy

Host galaxy: Massive reservoir of gas and dust = fuel for galaxy formation• Dust mass ~ 7e8 Mo

• Gas mass ~ 2e10 Mo

+

J1148+5251 z=6.42

Fine structure lines: [CII] 158um at z=6.4 Dominant ISM gas coolant = star formation tracer

z>4 => FS lines observed in (sub)mm bands

[CII] size ~ 6kpc ~ molecular gas => distributed star formation

SFR ~ 6.5e-6 L[CII] ~ 3000 Mo/yr

1”

[CII] + CO 3-2

[CII]

[NII]

IRAM 30m

Plateau de Bure

Break-down of black hole -- bulge mass relation at very high z: BH forms first?

High z QSO hosts

Low z QSO hosts

Other low z galaxies

Extreme downsizing: building giant elliptical galaxies + SMBH at tuniv < 1Gyr

Radio detections at z>5.7: only direct probe of host galaxies

10 dust (1/3 of QSO sample) => dust mass > 1e8 Mo

4 CO => gas mass > 1e10 Mo

2 [CII] => SFR > 1000 Mo/yr

10.5

8.1

Li et al.

Harvard models: stellar mass ~ 1e12 Mo forms in series of major, gas rich mergers starting at z~14, driving SFR > 1e3 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

Rapid enrichment of metals, dust, gas within 1 Gyr of Big Bang

Currently limited to pathologic objects (HyLIRGs: FIR > 1e13 Lo)

AOS Technical Building

•ALMA will have uJy line sensitivity in few hours => image gas, dust in ‘normal’ galaxies (LBGs, LAEs) to z ~ 10

•Early science: Q4 2010

Atacama Large Millimeter Array: an order of magnitude, or more, improvement in all areas of (sub)mm interferometry, at 5000m in Chile (‘half-way to the Moon’)

Dark Ages

15 < z < 200

Age of enlightenment

6 < z < 15

• Dark ages: < 90 MHz. HI 21cm signal is the only method for probing (linear) structure formation into Dark Ages. VLF => possible lunar imperative?

• Reionization: 100 MHz to 200 MHz, HI 21cm signal being explored by ‘path-finders’

Long History of Lunar Low Freq Telescope

Gorgolewski 1965: Ionospheric opacity

• Ionosphere p ~ 10 MHz

• ISM p ~ 0.1 MHz

• Interstellar scattering => size ~ 1o (/1 MHz)-2

• Faraday rotation => no polarization

• z > 140 => not (very) relevant for HI 21cm studies, ‘beyond dark ages’

New window

Lunar window

ion. cutoff ~ 30m

ISM cutoff ~ 3km

Return to moon is Presidential national security directive (an order, not a request).

Summary of STScI Workshop, Mario Livio, Nov. 2006

“The workshop has identified a few important astrophysical observations that can potentially be carried out from the lunar surface. The two most promising in this respect are:

(i) Low-frequency radio observations from the lunar far side to probe structures in the high redshift (10 < z< 100) universe and the epoch of reionization

(ii) Lunar ranging experiments…”

Our concensus: Lunar imperative awaits lessons from ground-arrays

Heavy lifting: future launch vehicles

Ares IAres I Ares VAres V

•10m diameter faring

•Lifting power = 65 tons to Moon

• Size ~ 1’ (z)-2 < typical scales of interest

• Scattering can lead to calibration errors => dynamic range limits

DR ~ N/(21/2 rad)Required DR ~ 1e6=> < 0.02o

Virgo A field, VLA 74 MHz Lane + 02

Lunar Advantage I: Ionospheric phase distortions

See talk by J. Lazio

Clementine (NRL) star tracker

Lunar ionosphere?-- LUNA orbiter detected plasma layer > 10 km above surface

-- Apollo surface+subsatellite: detected photoionized layer extending to 100km

-- p = 0.2 to 1 MHz

* large day/night variation

* small e does not necessarily imply small electronic pathlength variations

Advantage II: Interference

Lunar shielding of Earth’s auroral emission at low freq (Radio Astronomy Explorer 1975)

Alexander + 1975

12MHz

The Moon is radio protected

ARTICLE 22(ITU Radio Regulations)

Space servicesSection V – Radio astronomy in the shielded zone of

the Moon22.22 § 8 1) In the shielded zone of the Moon31 emissions causing harmful interference to radio astronomy observations32 and to other users of passive services shall be prohibited in the entire frequency spectrum except in the following bands:22.23 a) the frequency bands allocated to the space research service using active sensors;22.24 b) the frequency bands allocated to the space operation service, the Earth exploration-satellite service using active sensors, and the radiolocation service using stations on spaceborne platforms, which are required for the support of space research, as well as for radiocommunications and space research transmissions within the lunar shielded zone.22.25 2) In frequency bands in which emissions are not prohibited by Nos. 22.22 to 22.24, radio astronomy observations and passive space research in the shielded zone of the Moon may be protected from harmful interference by agreement between administrations concerned.

Other advantages

• Easier deployment: robotic or human

• Easier maintenance (no moving parts)

• Less demanding hardware tolerances

• Very large collecting area, undisturbed for long periods (no weather, no animals, not many people)

Avi

Miguel

z=50

z=150

NPS

Lunar challenges: dark age signal sensitivity

Statistical detection

•1 SKA, 1 yr, 30MHz (z=50), 0.1MHz

•TBsky = 100 (/200MHz)-2.7 K

= 1.7e4 K

At l=3000, k=0.3 Mpc-1

• Signal ~ 2 mK

• Noise PS ~ 1 mK

Requires few SKAs

Apollo 15

• Array data rates (Tb/s) >> telemetry limits, requiring in situ processing, ie. low power super computing (LOFAR/Blue Gene = 0.15MW)

• RFI shielding: How far around limb is required?

• Thermal cycling (mean): 120 K to 380 K

• Radiation environment

• Regolith: dielectric/magnetic properties

Other challenges

Lunar shielding at 60kHz

Takahashi + Woan

Tsiolkovsky crater

(100 km diameter)

20°S 129°E

Apollo 15

Solution: polar craters of eternal darkness, peaks of eternal light = eternal power

But how sharp is the knife’s edge?

DALI - LAMA: A path to enlightenment

NASA funded joint design study

• Dark Ages Lunar Interferometer (Lazio)

• Lunar Array for Measuring 21cm Anisotropies (Hewitt)

Science (Loeb, Furlanetto)

Science requirements (Carilli, Taylor)

Antennas (Bradley, MacDowall)

Receivers (Backer, Ellingson)

Correlator (Ford, Kasper)

Data communication (Ford, Neff)

Site selection (Hoffman, Burns)

Deployment (de Weck, DeMaio)

Engineering: power/mech/therm

Goal: DS2010 white paper with mission concept, (rough) costing, and technological roadmap

2010 -- 2020: technology development

<2010: mission concept study

2020 -- 2025: Design/Fabrication/Test

2026+: operations

Interim programs

•Orbiter: RFI, ion

• First dipoles: environ., phase stability

• Global signal

+ ARES V Launch fee ~ $700M

Total ~ $2G

Budget WAG (Hewitt/LARC)

Say, its only a PAPER moonSailing over a cardboard seaBut it wouldn't be make-believeIf you believed in me

Rich

Don

END

(sub)mm: high order molecular lines. fine structure lines -- ISM physics, dynamics

cm telescopes: low order molecular transitions -- total gas mass, dense gas tracers

Pushing to first normal galaxies: spectral lines

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

SMA

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.

, GBT

European Aeronautic Defence and Space Corporation/ASTRON (Falcke)

• Payload = 1000 kg (Ariane V)

• 100 antennas at 1-10 MHz ~ 1/10 SKA

QuickTime™ and aYUV420 codec decompressor

are needed to see this picture.

FIR excess -- 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: ISM physics at z=6.42

NGC253

MW

Deployment

•Javelin

• ROLS: polyimide circuit-imprinted film

• Dipoles: robotic with rover

• Dipoles manually

100 people km^-2

1 km^-2

0.01 km^-2

Chippendale & Beresford 2007

Moon?

100 people km^-2

1 km^-2

0.01 km^-2

0 km^-2

Lunar advantage II: terrestrial interference shielding