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Peering into the Birthplaces of Solar Systems

This article discusses the groundbreaking early observations from the Atacama Large Millimeter/submillimeter Array (ALMA) and the Expanded Very Large Array (EVLA) focused on circumstellar disks. These observations reveal critical information about the formation and evolution of planetary systems, examining disks around young stars such as TW Hya and HR 8799. The findings highlight the potential of radio astronomy in tracing mass, detecting chemical compositions, and dissecting the processes involved in planet formation. The article emphasizes the importance of high sensitivity and resolution in studying these celestial environments.

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Peering into the Birthplaces of Solar Systems

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  1. Early ALMA and EVLA Observations of Circumstellar Disks Peering into the Birthplaces of Solar Systems K. Teramura UH IfA David J. Wilner Atacama Large Millimeter/submillimeter Array Expanded Very Large Array Robert C. Byrd Green Bank Telescope Very Large Baseline Array Harvard-Smithsonian Center for Astrophysics

  2. From Disks to Planets Silhouette Disks in Orion Nebula around ~1 Myr-old stars Planets Orbting HR8799 Astro2010: How do circumstellar disks evolve and form planetary systems? Marois et al. 2008, 2010 McCaughren & O’Dell 1995 AAAS, February 2012

  3. Relevance of Radio Astronomy • avoid high dust opacities mass tracer • many spectral lines diagnostics, kinematics • sensitive to cold material including mid-plane • contrast with star planet-forming region • high sensitivity and angular resolution ALMA and EVLA! ALMA EVLA AAAS, February 2012

  4. Next Generation Radio Telescopes Atacama Large Millimeter Array Expanded Very Large Array • 66 moveable 12m/7m antennas 5000 m site in northern Chile l= 300 mm to 3 mm • global collaboration (NA, EU, EA) to fund >$1B construction • 27 moveable 25 m antennas 2000 m site in New Mexico l= 7 mm to 4 m • modern electronics and signal processing, c. 1980 infrastructure 10-100x better sensitivity, spectral capabilities, resolution AAAS, February 2012

  5. Some Early Disk Observations ALMA Science Verification: TW HyaProtoplanetary Disk test system validity, data released to community disks@EVLA key project: Grain Growth and Structure PI Claire Chandler (NRAO) and 17 co-I’s worldwide ALMA Early Science: Fomalhaut Debris Disk PI Aaron Boley (U. Florida) and 5 co-I’s • These results already showcase the extraordinary science potential of the new radio telescopes. • Many more amazing observations are underway. AAAS, February 2012

  6. TW Hya Background • closest gas-rich ~few Myr-old disk (160 ly) • isolated, viewed nearly face-on • southern sky • many studies with Submillimeter Array HST, Weinberger et al. 2002 Doppler shift Andrews et al. 2011 Qi et al. 2004 AAAS, February 2012

  7. TW Hya CO J=3-2 from ALMA Keplerian model/data comparison – can you tell the difference? • incredible data (from a small fraction of ALMA)! AAAS, February 2012

  8. TW Hya DCN J=3-2 from ALMA imaging a deuterated, nitrogen-bearing, triatomic molecule (!) • Earth’s oceans are enriched in deuterium • deuteration is associated with low temps: • H3+ + HD H2D+ + H2 + DE • water delivery from cold, outer Solar System? (by comets) Hartogh et al. 2011 AAAS, February 2012

  9. TW Hya DCN J=3-2 from ALMA SMA DCO+: D/H enhancement at large disk radii supports in situ deuteration at low T in outer disk • DCN distribution is different! Qi et al. 2008 Oberg et al. 2012 • water delivered from cold, outer Solar System? • evidence for multiple pathways to deuterium enhancement in disks AAAS, February 2012

  10. From Dust to Planets radio spectral signatures planet-disk interactions Planetesimal formation Planet formation Debris Gravity- assisted growth Gas capture Collisionalagglomoration ??? (collective effects) Collisons 1mm 1mm 1m 1km 1000km <1km AAAS, February 2012

  11. Spectral Signatures of Grain Growth mm/cm dust emissivity ~ l- b is diagnostic of maximum grain size previous VLA results b 0 2 “pebbles” ISM grains see Draine 2006 b Rodmann et al. 2006 AAAS, February 2012

  12. Disks@EVLA Key Project (PI Chandler) grain growth and substructure in protoplanetary disks: last observable link in chain from ISM to planets photometry of 60+ disks at 7/9/13/50 mm spectral indices reveal large grains reduction and modeling underway imaging of subsets, to 50 mas = few AU surface densities, disk-planet interactions observations ongoing expect resolved mm/cm colors K. Teramura UH IfA AAAS, February 2012

  13. (Preliminary) EVLA Taurus Disk Images Chandler et al, in prep l = 9 mm (30.5 and 37.5 GHz) θ~ 0.7 arcsec = 100 AU spectral indices AAAS, February 2012

  14. TW Hya: Planet-Disk Interaction • giant planet opens disk gap and creates cavity • 4 AU radius cavity (barely) detected with VLA Hughes et al. 2007 P. Armitage: jila.coloarado.edu/~pja AAAS, February 2012

  15. TW Hya: Planet-Disk Interaction • should be easy to detect with EVLA and ALMA at the limits of ALMA Wolf & D’Angelo 2005 AAAS, February 2012

  16. Fomalhaut Background ~200 Myr-old nearby star (25 ly) with dusty debris • directly imaged orbiting planet possible circumplanetary disk? Kalas et al. (2008) AAAS, February 2012

  17. Fomalhaut with ALMA at 870 mm ALMA Cycle 0 Reference Image rms noise 70 mJy PI Boley: measure thermal dust emission from known circumstellar material and potentially circumplanetary dust near Fomalhautb using the compact (3 hrs) and extended early science antenna configurations 1.5” x 1.2” Boley et al. in prep. 20 arcseconds ~ 150 AU AAAS, February 2012 Kalas et al. (2009)

  18. Underway inALMA Cycle 0… young disks: Orion, brown dwarfs, binaries, chemistry, gas/dust structure, dynamics PIs: Mann, Akeson, Ricci, Qi, Lin, Carpenter, Salyk, Chapillon, Walsh old disks: debris, birth rings, Herschel cold disks PIs: Rodriguez, Jordan, Carpenter, Boley, Wilner, Woitke in-between disks: gas-poor/dust-rich, gas-rich/dust-poor, gas in cavities, dust in cavities, unusually small/large disks PIs: Dutrey, Andrews, Chapillon, Casassus, van Dishoek, Perez, Schreiber, Kospal disks and planets: interactions PIs: Jordan, Huelamo, Boley AAAS, February 2012

  19. A new “Radio Era” for Disk Studies • large samples of planet-forming disks now within reach • major unknown is distribution/evolution of cold dust and gas at Solar System scales:key observables for ALMA and EVLA • amazingprospects • expect surprises! at the limits of ALMA AAAS, February 2012

  20. AAAS, February 2012

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