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A New Sample of Massive Young Stellar Object Outflow Candidates : Extended Green Objects from the GLIMPSE Survey. Claudia Cyganowski (University of Wisconsin-Madison). Collaborators: Crystal Brogan (NRAO) Ed Churchwell (Wisconsin) Todd Hunter (NRAO) Barb Whitney (Wisconsin)
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A New Sample of Massive Young Stellar Object Outflow Candidates: Extended Green Objects from the GLIMPSE Survey Claudia Cyganowski (University of Wisconsin-Madison) Collaborators: Crystal Brogan (NRAO) Ed Churchwell (Wisconsin) Todd Hunter (NRAO) Barb Whitney (Wisconsin) Qizhou Zhang (CfA) Great Barriers in High Mass Star Formation, September 13, 2010
IRAS MSX Spitzer (IRAC) Cyganowski et al. (2008) RGB: 100, 25, 12 m Resolution ~ 0.5’-2’ RGB: 21.4, 12.1, 8.3 m Resolution ~ 18” RGB: 8.0, 4.5, 3.6 m Resolution ~ 2” The Evolution of IR-selected MYSO samples… (c)
A New Diagnostic: Spitzer’s 4.5m band Spitzer, 3.6um-24um (with <6” resolution) Image: NASA/JPL-CalTech Reach et al. (2006)
A New MYSO Outflow Sample: GLIMPSE Extended Green Objects (EGOS) > 300 EGOs cataloged in GLIMPSEI survey area Cyganowski et al. (2008) Red: 8.0um, Green: 4.5um, Blue: 3.6um
EGO Survey Results: Spatial Distribution of CH3OH Masers GLIMPSE Images: Red: 8um Green: 4.5um Blue: 3.6um Yellow contours: MIPS 24 um + 44 GHz Class I CH3OH masers 6.7 GHz Class II CH3OH masers Cyganowski et al. (2009)
EGO Survey Results: Kinematics HCO+ 6.7 GHz maser 44 GHz maser H13CO+ Cyganowski et al. (2009)
EGO Survey Results: Summary • 6.7 GHz CH3OH maser detection rate >64% • Nearly 2x detection rate of other MYSO samples • Centrally concentrated, coincident with 24µm emission • 44 GHz CH3OH maser detection rate ~ 89% • Spatially distributed, coincident with 4.5µm emission • Velocities near systemic • HCO+ (3-2) line profiles indicative of outflows (broad line wings) • SiO (5-4) detection rate 90% recent shocks, active outflows • 95% nondetection rate for bright 44 GHz continuum emission most EGOs are not UC HII regions • Bottom line: Surveyed EGOs are young MYSOs with active outflows, and hence presumably ongoing accretion
~0.18 pc SiO(5-4) EGO Survey Results: Methanol Masers and Thermal Line Emission G11.92-0.61 Image: Red: 8um, Green: 4.5um, Blue: 3.6um (GLIMPSE) Yellow contours: MIPS 24 um Magenta Crosses: 44 GHz Class I CH3OH masers Black Diamonds: 6.7 GHz Class II CH3OH masers Cyganowski et al. (2009)
Molecular Bipolar Outflows: G11.92-0.61 SMA CARMA CARMA 12CO (2-1) HCO+ (1-0) SiO (2-1) Outflow properties Mred: 0.2 Msun Mblue: 0.6 Msun Mtotal: 0.8 Msun Length: 0.6 pc tdyn: ~ 5-6 x 103 yrs Mass outflow rate: ~ 1.3 x 10-4 Msun/yr Outflow properties Mred: 2.6 Msun Mblue: 5.2 Msun Mtotal: 7.8 Msun Length: 0.6 pc Mass outflow rate: ~ 1.4 x 10-3 Msun/yr VLSR~ 35 km/s Red: v~ 45-54 km/s Blue: v~ 8-25 km/s ~VLSR 10 km/s VLSR~ 35 km/s Red: v~ 48-71 km/s Blue: v~ -24-22 km/s ~VLSR 13 km/s GLIMPSE images: Red: 8um, Green: 4.5um, Blue: 3.6um Black Contours: 1 mm continuum (CARMA) Magenta crosses: 44 GHz Class I CH3OH masers Cyganowski et al., submitted
CH3OH Compact Cores: G11.92-0.61 From CARMA 1 mm continuum: SMA (3” res.): Mgas=26-62 Msun Tdust=40-20 K 3 Mgas=17-42 Msun Tdust=40-20 K 2 Mgas=3-9 Msun Tdust=80-30 K Mgas=2-6 Msun Tdust=80-30 K Best fit two-component model: Cool: T = 77 K Size = 3.0” (0.06 pc, 11400 AU) N(CH3CN) = 1.1 x 1015 cm-2 Warm: T = 166 K Size = 0.6” (0.01 pc, 2300 AU) N(CH3CN) = 2.3 x 1017 cm-2 Best fit single component model: T = 140 K Size = 1.0” (0.02 pc, 3800 AU) N(CH3CN) = 3.3 x 1016 cm-2 CH3CN(12-11) 6” 0.11 pc 22800 AU 1 Mgas=5-13 Msun Tdust190-70 K Mgas=8-24 Msun Tdust=190-70 K Greyscale: MIPS 24 um Blue contours: CARMA 1 mm continuum Red contours: GLIMPSE 8um Filled : H2O maser : 6.7 GHz CH3OH masers +: 44 GHz CH3OH masers Cyganowski et al., submitted
EGO Survey Results: Methanol Masers and Thermal Line Emission G19.01-0.03 ~0.20 pc SiO(5-4) Image: Red: 8um, Green: 4.5um, Blue: 3.6um (GLIMPSE) Yellow contours: MIPS 24 um Magenta Crosses: 44 GHz Class I CH3OH masers Black Diamonds: 6.7 GHz Class II CH3OH masers Cyganowski et al. (2009)
SMA CARMA CARMA HCO+ (1-0) 12CO(2-1) SiO (2-1) tdyn 3600 yrs tdyn 1100 yrs tdyn 600 yrs Molecular Bipolar Outflows: G19.01-0.03 12CO(2-1) emission near the vLSR is dominated by an extended envelope, suggesting the source is very young. Outflow properties Mred: 0.1 Msun Mblue: 0.4 Msun Mtotal: 0.5 Msun Length: 0.7 pc tdyn: ~ 3 x 103 yrs (blue) ~16 x 103 yrs (red) Mass outflow rate: ~ 1.3 x 10-4 Msun/yr Outflow properties Mred: 2.4 Msun Mblue: 6.5 Msun Mtotal: 8.9 Msun Length: 0.8 pc Mass outflow rate: ~ 1.8 x 10-3 Msun/yr VLSR~ 60 km/s Red: v~ 69-83 km/s Blue: v~ 8-52 km/s VLSR~ 60 km/s Red: v~ 66-83 km/s Blue: v~ 26-53 km/s VLSR~ 60 km/s Red: v~ 76-89 km/s Blue: v~ -46-20 km/s GLIMPSE images: Red: 8um, Green: 4.5um, Blue: 3.6um Black Contours: 1 mm continuum (SMA) Black : 6.7 GHz CH3OH masers Magenta +: 44 GHz CH3OH masers
Best fit single component model: T = 114 K Size = 0.6” (0.01 pc, 2500 AU) N(CH3CN) = 1.7 x 1016 cm-2 k=1 k=0 k=3 k=2 k=4 k=5 k=6 Compact Core: G19.01-0.03 Dust Mass From 3mm continuum (~6” resolution): Mgas=31-40 Msun (Tdust=130-100K) From 1mm continuum (~3” resolution): Mgas=12-16 Msun (Tdust=130-100K) Images (GLIMPSE): Red: 8um, Green: 4.5um, Blue: 3.6um Black Contours: 1 mm continuum (SMA). Yellow Contours: 24 um (MIPS) Black : 6.7 GHz CH3OH masers Magenta +: 44 GHz CH3OH masers Cyganowski et al., submitted
HCO+ Results from mm observations: • Diversity: • One EGO is associated with a cluster of at least 3 compact cores; the other appears to be single • Members of the (proto)cluster may span a range of evolutionary states • Complex outflow morphology and kinematics: multiple flows or unresolved (proto)binary? • Evidence for an age spread among EGOs: • Variation in strength and richness of hot core signatures (CH3CN, S-bearing species) • Proportion of mass remaining in extended envelope v. compact cores • In both EGOs studied: • Bipolar molecular outflows, traced by 12CO, SiO, and HCO+, coincident with the 4.5 m lobes • Strong SiO emission recent shocks, active outflows • Driving source is coincident with a compact mm core and exhibits hot-core line emission (thermal CH3OH, CH3CN, OCS) • Class I 229.759 GHz CH3OH maser emission coincident with 44 GHz masers (4th and 5th known examples) • Observed EGOs are young MYSOs driving massive bipolar outflows • For the Future: • High resolution follow-up of possible ionized gas • Greater diversity of EGOs observed in the (sub)millimeter • Far-IR data to assess SEDs and Lbol