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Lunatic fringe: probing the dark ages from the dark side of the Moon

Lunatic fringe: probing the dark ages from the dark side of the Moon C. Carilli (NRAO), Sackler Cosmology Conf, Cambridge, MA, 2008. Judd. Jackie. CO3-2 VLA S  ~ 0.6 mJy. 1” ~ 6kpc. Radio astronomy pushing into reionization: gas, dust, star formation in QSO host galaxies at z>6.

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Lunatic fringe: probing the dark ages from the dark side of the Moon

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  1. Lunatic fringe: probing the dark ages from the dark side of the Moon C. Carilli (NRAO), Sackler Cosmology Conf, Cambridge, MA, 2008 Judd Jackie

  2. CO3-2 VLA S ~ 0.6 mJy 1” ~ 6kpc Radio astronomy pushing into reionization: gas, dust, star formation in QSO host galaxies at z>6 J1148+5251 z=6.42 + • Supermassive black hole: • Lbol = 1e14 Lo • Black hole: ~3 x 109 Mo • Gunn Peterson trough => near edge of reionization • Host galaxy: Massive reservoir of gas and dust = fuel for galaxy formation • Dust mass ~ 7e8 Mo • Gas mass ~ 2e10 Mo

  3. 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 IRAM 30m [CII] [NII] Plateau de Bure 1” [CII] + CO 3-2

  4. 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

  5. Extreme downsizing: building giant elliptical galaxies + SMBH at tuniv< 1Gyr 10.5 Li et al. 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 8.1 • 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)

  6. 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’) 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

  7. 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’ Dark Ages 15 < z < 200 Age of enlightenment 6 < z < 15

  8. 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

  9. 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: 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 Lunar ranging experiments…” Our concensus: Lunar imperative awaits lessons from ground-arrays

  10. Heavy lifting: future launch vehicles • 10m diameter faring • Lifting power = 65 tons to Moon Ares I Ares V

  11. Lunar Advantage I: Ionospheric phase distortions • 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

  12. 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 edoes not necessarily imply small electronic pathlength variations Clementine (NRL) star tracker See talk by J. Lazio

  13. Advantage II: Interference Lunar shielding of Earth’s auroral emission at low freq (Radio Astronomy Explorer 1975) 12MHz Alexander + 1975

  14. ARTICLE 22 (ITU Radio Regulations) Space services Section V – Radio astronomy in the shielded zone of the Moon 22.22 § 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. The Moon is radio protected

  15. 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) Miguel Avi

  16. z=50 NPS z=150 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

  17. Other challenges • 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 Lunar shielding at 60kHz Takahashi + Woan Apollo 15

  18. Solution: polar craters of eternal darkness, peaks of eternal light = eternal power Tsiolkovsky crater (100 km diameter) 20°S 129°E But how sharp is the knife’s edge? Apollo 15

  19. 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

  20. Interim programs • Orbiter: RFI, ion • First dipoles: environ., phase stability • Global signal <2010: mission concept study 2010 -- 2020: technology development 2020 -- 2025: Design/Fabrication/Test 2026+: operations

  21. Budget WAG (Hewitt/LARC) + ARES V Launch fee ~ $700M Total ~ $2G

  22. Say, its only a PAPER moon Sailing over a cardboard sea But it wouldn't be make-believe If you believed in me Don Rich

  23. END

  24. 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.

  25. European Aeronautic Defence and Space Corporation/ASTRON (Falcke) • Payload = 1000 kg (Ariane V) • 100 antennas at 1-10 MHz ~ 1/10 SKA

  26. Continuum SED and CO excitation: ISM physics at z=6.42 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

  27. Deployment • Javelin • ROLS: polyimide circuit-imprinted film • Dipoles: robotic with rover • Dipoles manually

  28. Chippendale & Beresford 2007 Lunar advantage II: terrestrial interference shielding 100 people km^-2 100 people km^-2 1 km^-2 1 km^-2 0.01 km^-2 0.01 km^-2 Moon? 0 km^-2

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