star and planet formation with sofia neal evans, john bally, jim de buizer, murad hamidouche, thomas...
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Star and Planet Formation with SOFIA
Star and Planet Formation with SOFIA
Neal Evans, John Bally,
Jim De Buizer, Murad Hamidouche, Thomas Henning, Goran Sandell, Floris van der Tak,
Ewine van Dishoeck
Neal Evans, John Bally,
Jim De Buizer, Murad Hamidouche, Thomas Henning, Goran Sandell, Floris van der Tak,
Ewine van Dishoeck
Sub-Themes and MembershipSub-Themes and Membership
The formation of massive stars– Membership: Jim De Buizer (SOFIA), John Bally (U.
Colorado), Floris van der Tak (SRON), Göran Sandell (SOFIA)
Astrochemistry of star formation– Membership: Ewine van Dishoek (Leiden Obs), Thomas
Henning (MPIfA), Floris van der Tak
The formation and evolution of disks– Membership: Murad Hamidouche (SOFIA), Thomas
Henning, Neal Evans, Jim De Buizer, John Bally
The formation of massive stars– Membership: Jim De Buizer (SOFIA), John Bally (U.
Colorado), Floris van der Tak (SRON), Göran Sandell (SOFIA)
Astrochemistry of star formation– Membership: Ewine van Dishoek (Leiden Obs), Thomas
Henning (MPIfA), Floris van der Tak
The formation and evolution of disks– Membership: Murad Hamidouche (SOFIA), Thomas
Henning, Neal Evans, Jim De Buizer, John Bally
Activities Since Last MeetingActivities Since Last Meeting
June 18 - First telecon of whole working group– Establishment of subthemes, membership to
work on those subthemes
June 18 to July 07 – Subgroups exchanged ideas and text via email, leads collated and wrote (~5pg) summaries
July 09 – I distilled the three texts into a zero-th order (~10pg) draft, released to subthemes for further iteration via email
June 18 - First telecon of whole working group– Establishment of subthemes, membership to
work on those subthemes
June 18 to July 07 – Subgroups exchanged ideas and text via email, leads collated and wrote (~5pg) summaries
July 09 – I distilled the three texts into a zero-th order (~10pg) draft, released to subthemes for further iteration via email
The Importance of Massive StarsThe Importance of Massive Stars
The Richness of AstrochemistryThe Richness of Astrochemistry
Disk StructureDisk Structure
SAFIRESAFIRE, , HAWCHAWC, FORCASTFORCAST
Disk SED model of the T Tauri star LkCa15 (Chiang et a. 2001).
SOFIA’s NicheSOFIA’s Niche
After IRAS, ISO, KAO, Spitzer Contemporary with Herschel, JWST, ALMA The wavelength region 28-60 microns
– Between JWST and Herschel Lack of saturation problems High Spectral Resolution (MIR to FIR) Flexibility, long operating timebase Most projects use SOFIA as complement to other
telescopes
After IRAS, ISO, KAO, Spitzer Contemporary with Herschel, JWST, ALMA The wavelength region 28-60 microns
– Between JWST and Herschel Lack of saturation problems High Spectral Resolution (MIR to FIR) Flexibility, long operating timebase Most projects use SOFIA as complement to other
telescopes
Massive Star Formation in Galactic Context
Massive Star Formation in Galactic Context
Surveys in mm continuum finding 1000’s of dense clumps– Bolocam Galactic Plane Survey– Complementary survey from APEX
Infrared Dark Clouds (IRDC)– MSX, GLIMPSE, MIPSGAL
New models of Galaxy, VLBA distances, … Provide link to extragalactic star formation
Surveys in mm continuum finding 1000’s of dense clumps– Bolocam Galactic Plane Survey– Complementary survey from APEX
Infrared Dark Clouds (IRDC)– MSX, GLIMPSE, MIPSGAL
New models of Galaxy, VLBA distances, … Provide link to extragalactic star formation
The New Milky WayThe New Milky Way
A Piece of the PlaneA Piece of the Plane
A very small piece of the BGPS showing the wealth of sources. Many, but not all, will be IRDCs
IRDCsIRDCs
Need for SOFIANeed for SOFIA
Massive stars are distant, form in clusters, produce copious PAH emission, high L, heavy extinction
Need better spatial resolution, imaging between PAH bands, avoid saturation– Imaging from 28-60 microns to separate L
sources– High-R spectroscopy to study dynamics
Massive stars are distant, form in clusters, produce copious PAH emission, high L, heavy extinction
Need better spatial resolution, imaging between PAH bands, avoid saturation– Imaging from 28-60 microns to separate L
sources– High-R spectroscopy to study dynamics
Nebulosity Hides StarsNebulosity Hides Stars
CS contours of dense core overlaid on GLIMPSE image of W51W (blue is 3.6 micron, green 4.5, red 8.0)
High-R ObservationsHigh-R Observations
Complementary to ALMA Tracers of higher temperature, density
– CASIMIR, GREAT, EXES– TEXES has shown that MIR absorption probes
different gas, very close to the star, perhaps in a disk.
Complementary to ALMA Tracers of higher temperature, density
– CASIMIR, GREAT, EXES– TEXES has shown that MIR absorption probes
different gas, very close to the star, perhaps in a disk.
Other IdeasOther Ideas
Use HAWC-Pol – constrain location and nature of aligned grains– Test importance of magnetic fields vs.
turbulence
Time variable phenomena– Outbursts due to stellar mergers, major
accretion events– Occultations
Use HAWC-Pol – constrain location and nature of aligned grains– Test importance of magnetic fields vs.
turbulence
Time variable phenomena– Outbursts due to stellar mergers, major
accretion events– Occultations
AstrochemistryAstrochemistry
Central Ideas– Trace the Oxygen– Trace the Water– Chemical Effects of outflows and shocks
Central Ideas– Trace the Oxygen– Trace the Water– Chemical Effects of outflows and shocks
Where are the Oxygen Atoms?Where are the Oxygen Atoms?
About 1/3 of the O is unaccounted for. OI 63 micron emission “ubiquitous” from ISO
– But abundances not well constrained– Apparently optically thick and subthermal– Need the line profile: GREAT is unique.
About 1/3 of the O is unaccounted for. OI 63 micron emission “ubiquitous” from ISO
– But abundances not well constrained– Apparently optically thick and subthermal– Need the line profile: GREAT is unique.
Follow the WaterFollow the Water
Herschel has major programs– SOFIA can add complementary information
– Some H218O lines at THz
– EXES ro-vibrational lines Can trace water evaporation region
Herschel has major programs– SOFIA can add complementary information
– Some H218O lines at THz
– EXES ro-vibrational lines Can trace water evaporation region
Shock ChemistryShock Chemistry
Theory expects shocks to drive O into water Not well tested
– Water, OH, O I lines, all with high-R
Theory expects shocks to drive O into water Not well tested
– Water, OH, O I lines, all with high-R
DisksDisks
Very interesting, but hard to find unique niche– Origin of the disk
Separating disk from infalling envelope 28-60 micron is key region Need a well-sampled SED in this region
– Later stages Residual envelope may confuse disk models Use SOFIA resolution to see if FIR resolved
Very interesting, but hard to find unique niche– Origin of the disk
Separating disk from infalling envelope 28-60 micron is key region Need a well-sampled SED in this region
– Later stages Residual envelope may confuse disk models Use SOFIA resolution to see if FIR resolved
Disk-Envelope SeparationDisk-Envelope Separation
Passive Disks Disk with intrinsic L
Points and red line are data; blue line is model.Model with passive disk inside envelope cannot fit 20-70 micron Need to add “disk emission”, but could be inner envelope.
Evolution of Materials for Planet Building
Evolution of Materials for Planet Building
Multiwavelength data probe grain growth Ice is key to forming giant planets
– 45 micron ice feature (Unique to SOFIA)– 6 micron MIR lines indicate evaporation– Evidence from Spitzer and TEXES
Multiwavelength data probe grain growth Ice is key to forming giant planets
– 45 micron ice feature (Unique to SOFIA)– 6 micron MIR lines indicate evaporation– Evidence from Spitzer and TEXES
Status and Schedule for WritingStatus and Schedule for Writing
Current status: “zero-th order” draft with ongoing changes by working group
Schedule:– Present to Aug 1: Further edits and address
feasibility with SOFIA– Aug 1: Official first draft distributed by Neal– Aug 18: Deadline for all comments from group– Aug 22: Full draft to SOFIA Vision Group
Current status: “zero-th order” draft with ongoing changes by working group
Schedule:– Present to Aug 1: Further edits and address
feasibility with SOFIA– Aug 1: Official first draft distributed by Neal– Aug 18: Deadline for all comments from group– Aug 22: Full draft to SOFIA Vision Group