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Questions that Remain to be Answered...

Questions that Remain to be Answered. +=dense core. CS (2  1). “Clump” Mass Distribution. Ω. What is a clump?. Structure-Finding Algorithms. Typical Stellar IMF. Salpeter 1955 Miller & Scalo 1979. What does the clump “IMF” look like?. CLUMPFIND ( Williams et al. 1994 )

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Questions that Remain to be Answered...

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  1. Questions that Remain to be Answered...

  2. +=dense core CS (21) “Clump” Mass Distribution Ω What is a clump? Structure-Finding Algorithms Typical Stellar IMF Salpeter 1955 Miller & Scalo 1979 What does the clump “IMF” look like? • CLUMPFIND (Williams et al. 1994) • Autocorrelations (e.g. Miesch & Bally 1994) • Structure Trees (Houlahan & Scalo 1990,92) • GAUSSCLUMPS (Stutzki & Güesten 1990) • Wavelets (e.g. Langer et al. 1993) • Complexity (Wiseman & Adams 1994) • IR Star-Counting (C. Lada et al. 1994) • PCA (Heyer & Schloerb 1997) • Spec. Corr. Function (Rosolowsky et al. 1999) E. Lada 1992 E. Lada et al. 1991

  3. A New Proposal: Episodic ejections from precessing or wobbling moving source Required motion of 0.25 pc (e.g. 2 km s-1 for 125,000 yr)

  4. 67:55 H H 3 1 5 C H H 3 1 5 B 67:50 H H 3 1 5 A H H 4 1 5 HH 215P2 ) 0 HH 215P1 5 9 1 ( PV Cephei d 67:45 HH 315D H H 3 1 5 E 67:40 H H 3 1 5 F 20:46 20:45 ( 1 9 5 0 ) a PV Ceph 12CO (2-1) OTF Map from NRAO 12-m Red: 3.0 to 6.9 km s-1 Blue: -3.5 to 0.4 km s-1 Arce & Goodman 2000

  5. PV Ceph12CO (2-1) OutflowContours on 13CO (1-0) Map

  6. Position-Velocity Diagram for PV Ceph Outflow Gradient in Systemic Velocity! Blue Lobe Red Lobe 12CO (2-1) data from NRAO 12-m (Arce & Goodman 2000)

  7. PV C eph: CO (2-1) Spectra Near HH315 B Full-resolution IRAM 30-m Spectrum Most Blueshifted 14% Cloud Intermediate 35% Blueshift 11% NRAO 12-m Spectrum Smoothed 30-m Spectrum Least Blueshifted 40% Arce & Goodman 2000

  8. 68 05 30 HH 315C NRAO 12m Beam 00 IRAM 30m Beam 04 30 0.5 pc 00 HH 315B 03 30 00 02 30 00 20 45 45 30 15 00 RIGHT ASCENSION (J2000) The “Blue” Lobe of the PV Ceph Outflow least blueshifted intermediate blueshift most blueshifted 12CO (2-1) data from IRAM 30-m (Arce & Goodman 2000)

  9. + = T [K] A B5-IRS 5:An “Outflow” Component? 1.8 1.6 1.4 1.2 3.2 3.6 4.0 4.4 Velocity (km/sec) T [K] A Model: Cloud component "Outflow" component T = 3.4 K T = 2.2 K A A D v=1.2 km/sec D v=1.2 km/sec v =10.5 km/sec v = 9.3 km/sec o o Velocity [km/sec] Velocity [km/sec] Sum of both components Velocity [km/sec] 13CO(1-0) Data from FCRAO to appear in Arce & Goodman 2000

  10. Roughly 1/4 of all mass within box is at “outflow” velocities HH300 & B18w in Taurus Contours show CO (2-1) emission from 7.3 to 9.9 km s-1(nearby “ambient” velocity is 6.7 km s-1 Greyscale shows extinction based on IRAS 60 & 100 micron emission

  11. The Taurus Dark Cloud Complex B18W/HH300 Mizuno et al. 1995 13CO(1-0) integrated intensity map from Nagoya 4-m

  12. 4. How much of a molecular cloud complex was “moved” to its present location by an outflow? • Movie of Taurus, Gas Only • Movie of Taurus, with Stars Key: Blue 34% "Cloud" 56% Red 10% (by mass)

  13. YSO Outflows Move More Gas than WeThought 1. “Giant” Herbig-Haro Flows PV Cephei shows density & velocity structure--at least at low density--controlled by flow. 2. The Effect of Outflows on their host Cores B5: Evidence for a "Core" Component in 13CO 3. Are Some Dark Clouds Created by Outflows? HH300: Is B18w an Outflow Lobe? 4. How much of a molecular cloud complex was “moved” to its present location by an outflow? Taurus: A Lot

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