tan_frontiers11 - The Extremes of Star Formation Jonathan...

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Unformatted text preview: The Extremes of Star Formation Jonathan Tan Depts. of Astronomy & Physics University of Florida Why study massive star & star cluster formation? The First (Pop III) Stars were likely massive, some potentially supermassive stars, reionizing the universe and producing the first metals. Galaxies form and evolve by forming star clusters, where the influence of massive stars is paramount. Massive stars are what tend to be seen in distant galaxies. Planets form from the crumbs left over from star formation. Planet & star formation in star clusters can be influenced by massive star feedback. Supermassive black hole formation may be via massive star clusters or Pop III stars. Supermassive black hole accretion is likely to be regulated by star formation. What drives star formation? What inhibits star formation? A complicated, nonlinear process Some notation: Core -> star or close binary Clump -> star cluster Numerical models Wide range of scales (~12 dex in space, time) and multidimensional. Uncertain/unconstrained initial conditions/boundary conditions. Observations General theory of star formation Analytic theory Physics: Gravity vs pressure (thermal, magnetic, turbulence, radiation, cosmic rays) and shear. Heating and cooling, generation and decay of turbulence, generation (dynamo) and diffusion of B-fields, etc. Chemical evolution of dust and gas. Star Formation: Open Questions • Causation: external triggering or spontaneous gravitational instability? • Initial conditions: how close to equilibrium? • Accretion mechanism: turbulent and/or magnetically regulated fragmentation vs competitive accretion • Timescale: fast or slow (# of dynamical times)? • End result – – – – Initial mass function (IMF) Binary fraction and properties Initial cluster mass function (ICMF) Efficiency and Rate (& relation to galaxy-scale) How do these properties vary with environment? What are the pressures where massive stars form? What are the pressures where massive stars form? AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 What are the pressures where massive stars form? 02) (20 n s, le el Mu van y, E irle , Sh r se cob Ja AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 What are the pressures where massive stars form? AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 M (M 82 cC SS ra Cs dy & Gr a ha m 20 07 ) What are the pressures where massive stars form? AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 r rne ars . Tu gul cky, J re rf ir bulni wa o in d on, K s Cs SS John (K. nH~2x105cm-3 tff~1x105yr .) t al e What are the pressures where massive stars form? AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 What are the pressures where massive stars form? Massive Star Formation Theory Turbulent Core Model (McKee & Tan 2003) Star Cluster Formation Theory AV=200 A8!m=8.1 NH=4.2x1023cm-2 5cm-3 nH~2x10 GMC Evolution & =4800 M pc-2 ! ! Equilibrium Star Cluster Formation (Tan et al. 2006) tff~1x105yr SFR Theory GMC Collision Model (Tan 2000) AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 Star Formation Simulations: SPH and AMR SPH: hdisk B-fields Outflows R # of SPH particles to resolve disk around 1 star ~10x(10R/hdisk)2~10x1002~105! Growth of star from disk with md=0.1m* -> 106 part. per star (Inutsuka ea. 2007, PPV) Adaptive mesh refinement based on certain AMR: criteria, e.g. to resolve shocks, density contrasts, Jeans length. Good at resolving shocks, multi-phase ISM, and better at including magnetic fields (although complicated). Both SPH and AMR simulations of star E. Tasker formation need to include sink particles. Star Formation Simulations: SPH and AMR 1. Does the simulation have reasonable initial conditions and boundary conditions? 2. Does the simulation include the relevant physics on scales it can resolve? 3. Does the simulation include reasonable sub-grid physics? 4. How do the results of the simulation depend on resolution and on the sub-grid physics? 5. What are the simulation’s testable predictions? A simulated idealized disk galaxy Tasker & Tan (2009), Tasker (2011). 20kpc Flat rotation curve, axisymmetric fixed background potential (old stars & DM), Q=1 (for "=6km/s) from 2-10kpc. ENZO AMR 3D Hydro Atomic Cooling to 300K, 8pc resolution, “GMCs” identified as regions with nH>100cm-3, #ff=0.02 in “GMCs” (Krumholz & Tan 2007), FUV heating appropriate for Milky Way (Wolfire et al. 2003) fGMC = 0.44 Towards Sub-Parsec Scales Initial conditions for pseudo shearing-box simulations that can resolve down to ~0.1pc, T>=10K. ! Star formation (n >10 cm Diffuse FUV feedback crit 5 -3; m*=103M!) No star formation, no FUV feedback Butler, Van Loo, Tan... Effect of magnetic field • Smoothed initial conditions (except velocity profile) hydro 1µG 10µG Van Loo+ Milky Way Projection Dame et al. (2001) B. Smith Barnes ... Hernandez, O’Dougherty, Tan et al. (2011) Census of High and Medium Mass Protostars (CHaMP) 12CO (Dame et al. 2001) l =-60 to -80 deg b = -4 to +2 deg Recursive mapping of successively denser gas tracers to build a complete sample. 12CO 12CO 13CO 13CO C18O C18O Nanten CO survey (~3’ beam) Survey of Dense Molecular Gas (CHaMP) Barnes et al. 20kpc Dashed lines show approx. representation of CHaMP survey (Barnes et al.) What are the pressures where massive stars form? Massive Star Formation Theory Turbulent Core Model (McKee & Tan 2003) Star Cluster Formation Theory AV=200 A8!m=8.1 NH=4.2x1023cm-2 5cm-3 nH~2x10 GMC Evolution & =4800 M pc-2 ! ! Equilibrium Star Cluster Formation (Tan et al. 2006) tff~1x105yr SFR Theory GMC Collision Model (Tan 2000) AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 Mid-IR Extinction Mapping of Infrared Dark Clouds (Butler & Tan 2009, 2011; see also Peretto & Fuller 2009; Ragan et al. 2009; Battersby et al. 2010) G28.37+00.07 Spitzer - IRAC 8µm (GLIMPSE) Median filter for background around IRDC; interpolate for region behind the IRDC Correct for foreground -> Choose nearby clouds. BT09: analytic model BT11: observed saturation in independent cores 16’ ~Arcsecond scale maps of regions up to ! ~0.5 g cm-2; independent of dust temp. g cm-2 Distance from molecular line velocities -> M(!) MJy sr-1 Application to Filamentary IRDCs G035.39!00.33 Comparison to C18O (2-1) & (1-0) 3’ Filament appears consistent with virial equilibrium models of Fiege & Pudritz (2000). (Hernandez et al., in prep) (Hernandez & Tan 2011; Hernandez et al. 2011) Depletion factor map Widespread CO depletion Continuum Radiative Transfer Modeling Zhang & Tan (2011) boundary of the core ( 1.18 × 104 AU) expansion wave front ( 1.02 × 104 AU) sonic point ( 2.54 × 103 AU) star disk outflow cavity wall disk star rsub = 5.51 AU disk scale height rd = 449 AU Radiative Transfer Models Zhang &Tan (2011) see also: Robitaille et al. 2006; Molinari et al. 2008. Rotation and outflow axis inclined at 60˚ to line of sight. d=1kpc convolved with telescope beam $ = 1 g cm-2 Mcore = 60 M! m* = 8 M! mdisk = m*/3 Lbol = 6x103 L! b Figure 1: The relative simplicity of G35.2N (adapted from De Buizer 2006). (a) Left panel: 18µm emission (false color; Gemini-T-ReCS) overlaid with 15GHz emission (contours; Heaton & Little 1988, A&A, 195, 193) tracing the bipolar outflow from this massive protostar. MIR light only reaches us via the near-side, blueshifted outflow cavity. Blue and redshifted CO(3-2) emission approximately following this geometry has been reported by Gibb et al. (2003). The circle shows the 0.1pc diameter fiducial core of MT03 (see Fig. 2a). This also happens to be the approximate size of the FOV of our proposed ALMA observations. (b) Right panel: Zoom-in towards the protostar: 11.7µm emission (false color; Gemini-T-ReCS) at 0.35” !"#$%&'"(#)**+ resolution. Superposed are L’ infrared emission coincident with and immediately north of the to ∼16,000 AU by a B2.6 star. If the dust is made of gr infrared emission coincident with and immediately north of the withto ∼16,000 AU by a B2.6 the If the dust is made of gr infrared emission coincident and immediately north of star. to ∼16,000 AU by a position of G35.2N demonstrates that the infrared emission here one could heat out to the distance of source 6 with grains position of G35.2N demonstrates that the infrared emission here one could heat out to the distance of source 6 with grains position of emission. Thereis dominated by longer wavelength continuumG35.2N demonstrates that the infrared of 0.005 here still one could lower size a typical size emission mm, near the heat out to is dominated by longer wavelength continuum emission. Therea typical size of 0.005 mm, near the lower size is dominated by longer wavelength continuum emission. There- still assumed composition fore, the nature of the infrared emission is concluded to be However, if silicon carbide is the a typical size of 0. fore, the nature of the infrared emission is concluded to be However, if silicon carbide is the assumed composition fore, However, if than so predominantly continuum dust emissionthe natureoutflow cavfrom the of the infrared emission is concluded heating out much farther silicon dust, then one can get to be predominantly continuum dust emission from the outflow cavpredominantly continuum dust dust, then∼one canAU at the out dust, farther than g ity walls. This cavity was created by the molecular outflow, emission from the outflow cav-0.003 much then size canso namely, 52,000 get heating mm lower one limit. ity walls. This cavity was by namely, ∼ molecular at namely, shock heati which punched a hole increated ity walls. This materialwas created bypossibility of some the 0.003 mmfrom ∼52,000 AU the dense the molecular outflow, molecular cavity suris a the 52,000 AUoutflow, contribution lower size limit which punched a hole in the densethe center of G35.20 0.74. dense possibilityetof some contribution a possibility heati which punched a hole in rounding the young stellar source at molecular material sur- the is a molecular material surthough Fuller al. (2001) claim nois from shock of s detection of shock-e rounding the young stellar source at rounding the G35.20stellar source though Fuller et al. (2001) claim nothough Fullershock-( the center heating .74. detection of et al. at the center of G35.20 0.74. The central source is mostly likely directlyof youngthe 0walls H 2 in the region. Beaming of the MIR emission alo The central source isnorthern likelyThe central source found to likely directlyregion. 18µm the isotropic2 emissionregion. B directly heating the mostly H2 in the heatingBeaming of theHMIR the assumed in emission alo of this cavity. The mostly lobe of the outflow was is walls outflow axis, rather the walls than of this cavity. The northern lobe of the outflow The northern of this of the axis, rather could to outflow axis, rather above outflow was found also help emission grains be slightly blueshifted toward Earth (i.e., cavity.wasGibb et to lobeoutflow calculations, than the isotropicin heating assumed in CO by found al. be2003; in blueshifted toward Earth (i.e., in CO by Gibb et al. Earth (i.e., in CO by Gibb et al. help in derived from th slightly C i by Little et al. 1998). slightlythis fortuitous geabove calculations, be Given blueshifted toward aboveInterestingly, the MIR luminosity heating grains out. calculations, could also 2003; in C i by Littledirectly1998). Given thiscavity as a et al. 1998). Given this fortuitous an luminosityvalue of 1.6 # th out. Interestingly, the MIR estimated Interestingly, 1 out. derived from th color temperature gives geometry, we can see et al. into 2003; in C i fortuitous conthe outflow by Little geometry, we of the clearing away the material along see a con- intocoloroutflow cavitygives con- is all color temperature g ometry, we can as line of the temperature as a an estimated luminosity of # 1 Assuming the MIR luminosity the value of 1.6 the sequence can see directly into of outflow cavity our directly Assuming along luminosity all Assuming the MIR l the luminosity of typ sequence of the clearing away of sequence along our line of material of the clearing away of materialthe MIRour line of iscalculating a spectral the (an obvious underestimate) and sight by the outflow itself. (an obvious underestimate) and calculating a spectral typ sightThe the outflow itself. of G35.20 by.74, namely, sources by sources farther north (an obvious underest sight 0 the outflow itself. that bolometric luminosity using the method from De thatal. 0.74, gives a sources ∼B3,that bolometric De method with the The are expected to north of G35.20either in the outflownorth 0 sources farther itself et bolometric luminosity of 5–9, sources farther be knots of dustThe .74, namely, sources of G35.20 (2005) namely, value using theconsistentfrom lum et al. (2005) gives a value of 5–9, clumps of preexisting material that are being impingeditself of dust either in the outflow itself ∼B3,etconsistent with the al. the dust, even 5–9, are expected to be knots derived spectral type. In summary, all of(2005) gives a or are expected to be knots of dust either in the outflow upon all of the dust, G or by the outflow. Source material that are being impinged upon clumps of preexisting 6 lies 19,200clumps of preexisting materialderived sourceimpinged upon be heated directly bytype or AU from G35.2N and is that are spectral6, can In summary, derived spectral even out as being type. indeed bystill at an estimated dust color temperature ofG35.2N and is 19,200 as source G35.2N indeed be heated (as well as bea the outflow. Source 6 lies 19,200 AU from 112 K. This lies out AU from dust composition and size directly by ca out as source 6, G by the outflow. Source 6 is depending on 6, can and is depending of 112 composition size from other c still at an estimated dust 18.3 mtemperature of 112 K. This is still densities of this source though we cannot rule out contributions(as well as bea based on the 11.7 and color m flux at an estimated dust color temperature on dust K. This is anddepending on dust p rule based neglects11.7 possible effectsfluxsilicate absorptionand 18.3 mm though we cannotthis source though we other r based on the 11.7 (see De flux densities of 450µm heating mechanisms. out contributions fromcannot p and on the the and 18.3 mm of densities of this source and neglects the possible effectsandand neglects What is heating heating mechanisms of silicate absorption (see De As discussed in § Buizer et al. [2005] for method of silicate absorption (see De limitations). the possible effects heating mechanisms. 3.1, MIR source 3, coincident wit Figure 2: (a) Left: Analytic limitations). be heated method star As discussed the presumed infrared coincidentin § formation 3, southern wi Buizer et al. [2005]out?method andCore Accretion Modelforout to andemission from in §is3.1, MIR sourceAs discussed coun Buizer can [2005] of massive limitations). What heating the dust this far for Smaller dust grainset al. What is heating (McKee & Tan emission have the presumed infrared southern the the dust this far out? 2003; Zhang grains. 2011). Aheated out to ! cdust is collapsingbeaheated out increasing spectralfrom cou Smaller dust grains can befar out? range farther distances than large dust & Tan The typical sizeSmaller ore does notcan emission slope typ the dust this fiducial 60M grains from smoothly to from the inside-out, via an expansion wave, rotating supersonic infall region and accretion disk. The outflow cavity is shown continuum of interstellar grains large be 0.003–10 m and does not have a emission increasing spectralpresent typ slope at farther s the unshaded region,dust grains. The typical size typicaldust grains. Theregion,smoothly but instead is onlyhave a smo distances than is believed to fartherangle of m, thanrange showsdust inner typical size range a with opening distances Thelarge 51˚. inset the where the rotatingdoes not infall envelope joins of grain compositions believed to region of the mm, andsilicates, to18.31mscaleheight, and typicalgiven the is in thispresent of interstellar grains is include smooth astronomical typical dust only southern of interstellar grains is a thickness be continuumm, calculated emission continuum at the disk. The darker shaded be 0.003–10 disk shows believed dust0.003–10 mimplies thatbut instead accretion rateemi of m. This emission the is dominated implies that the graphite, -4 grain compositions include 18.3 m this southern grain ~2!10and!yr-1 to the 8M!smooth& astronomical silicates,image 18.3 mm.at 0.5” resolution (on the some kind. The usual su M silicon carbide (Laor protostar.Draine 1993; Draine & smooth µm Thisby line silicates, of same scale as Fig. 1a), (compositions Model b) Top Right: include at 18 astronomical emission emission inm. This implie are Draine flux per beam is Lee with northern following use& Draine 1993; 60˚carbide (Laor sight. H2 emission emission of somedominated usual su 1984). silicon carbide (Laor graphite, and silicon to the the equation at dust temgraphite, and In theoutflow axisIinclined towards usforDraine & line is dominated by lineDraineshocks, althoughthe topby line is in The et al. of &(1) Peak 1993; from & indicatedkind.Fuller right. claim H emission from shocks, althoughH emission perature In the Sellgrendensity relative to the ultraviolet ottom use thes no2detection of H2 temare A for (b), now dust in (ALMAare (2) PAH emissio Lee 1984).given byfollowing et al. (1983) and this for dust tem- I Right: (1)equation for at 450µmthe region; (1)9), 2with 0.23” the 1984). In the (c) Band Color scale shows flux I use Lee equation peak.following Band Fuller et al. the photodissociation region outflow detection o infrared emissivities of density (1983) and the355mJy/beam. et Lee (1984). by Sellgren claim and the ultraviolet and of theclaim PAH emissio perature given by SellgrenDraineis&perature givenAssuming the al. (1983)no detection of H2 in the region; (2)no interface w resolution. Peak flux et al. equivalent to ultraviolet and molecular cloud, although dust is made up of smooth astronomical silicates, dust of Draine & Lee (1984). Assuming theof L and photodissociatio the photodissociation regionthe thethe 18.3 mm filtersw outflow interface infrared emissivities of Draine & Lee (1984). Assuming thea infrared emissivities with4 encompass any dust with a (3) [Fe m filters lower size up of 0.003 astronomical made112 of smooth be heated to up K with a molecular cloud, although the and nd 18.3 ii memission dust is made limit ofsmooth mm can dust issilicates, dustonly out astronomical silicates,PAH features; L amolecular ]cloud, al Fig. 0.74 as seen at different wavelengths. () )The 11.7 m image in false color overlaid with K-band emission from Fuller et a different wavelengths. a The K-band Fig. r 2.—The G35.200.74 jetjet as seen at Fig. 2.—The G35.20 (a0.74 jet 11.7mmmimage in false color overlaid with 11.7 mmemission from Fuller et a 2.—The G35.20 as seen at different wavelengths. (a) The image in false color ove location white esolution and the 8.5 GHz high-resolution radio continuumet al. 2003; Gibbstrong(2003, gray contours). b the presumedimage in falsethe contours) 8.5GHz continuum (black contours; Gibb emission of the et al. source defines [0,0], The 18.3 mm image in of color white contours) and the 8.5 GHz high-resolution contours) and theemission of Gibb et al. (2003, gray contours). ((b)) The 18.3 mm al. (2003, false color white radio continuum 8.5 GHz high-resolution radio continuum emission (crosses; gray masers (asterisks; Hutawarakorn & Cohen (1988,MNRAS, 303,) 845), water masersof Gibb et Forster & conto with protostar). OH15 GHz radio continuum image of Heaton & Little 1999, white!"#$%&'"(#)**+ from Fuller et al. (2001, gray contours). whitecontours) and L iimage contours L mage with thethe low-resolution 15 GHz radio continuum image of Heaton & Little(1988, continuum image andHeaton from Fuller et al. (2001, gray contours). (( low-resolution with the low-resolution of Li in on the central region of the 11.7339)imagemethanol masersL contours in white and the high-resolution are continuum contours in black. The OH radio C central region of the 213, mm and in false color, the 15 GHz radio m image the high-resolutionL& Little (1988, white contours) and Themag in on theaswell 1989, A&A, 11.7 mm image in false color, the L (large plusmsigns; Gibb, priv. comm.) radioshown. Astrometric uncertaintyOH contours in white and continuum contours in black. in of Hutawarakorn & Cohen (1999) are shownonthe error water in of the 11.7 right.Caswellfalse color, theALMA to imagemasers ofcontinuum (2006 as the central region the of Forster & We in (1989) as crosses, contours in white and the high-resolution and methanol 450µm between & Cohen radio is shown by asterisks, bars masersof Forster & Caswell (1989) to use masers methanol masers of A. G. Gibb (2006 of Hutawarakorn MIR and (1999) areshown as asterisks, water Cohen (1999) are shown aspropose as crosses, andof Forster & CaswellA. G. Gibbcrosse of Hutawarakorn masers lower asterisks, water (1989) as and communication) as large plus signs. The bars at lower right& the j relative astrometric uncertainty between the radio for the accretion line emission in a ~9” FOV, resolving structures showthe 11between astrometric 1.5”, especially searching continuum and NIR.disk.b communication) as large plus signs. The bars at lower right as with sizes signs. The 0.23” and uncertainty between1therelativecontinuum and NIR. communication) show plus j relative bars at lower right show the large j radio astrometric uncertainty *+,*-*./.0*123.*420456,+/.*.7-185.* d=2.3 kpc No. 1, ,+20*9321*-0*26=952>?*02=*-*@+,AB LMIR~1.6x103L! 6 006 !"#$%&'&$()*+,*-*./.0*123.*420456,+/.*.7-185.* No. 1, 1, 2006 MID-INFRARED JET OF G35.20 MID-INFRARED JET OF G35.20 No. 1, 2006 No. 2006 MID-INFRARED JET OF G35.20 0.74 0.74 29*:;<*.1+,,+20*9321*-0*26=952>?*02=*-*@+,AB Gemini-T-ReCS (2003). The circle shows the 0.1pc diameter fiducial core of MT03 (see 11.7µm Fig. 2a). This alsoOF G35.20 be0the happens to MID-INFRARED JET OF G35.20MID-INFRARED JET OF G35.20 0.74 .74 L59 2006 L59 MID-INFRARED size of the FOV of our 0.74 L59 approximate JET proposed ALMA observations. (b) Right panel: Zoom-in towards the ALMA protostar: 11.7µm emission (false color; Gemini-T-ReCS) at 0.35” SOFIA-FORCAST 11.7µm !"#$%&'"(#)**+ 18µm resolution. Superposed are L’ continuum (white contours; Fuller et al. 2001, ApJ, 555, .74 and high different wavelengths. (a) The 11.7 mm image in false 125) Fig. 2.—The 0 overlaid with K-band emission from Fig. resolutionG35.200.74 jetjet as seen at Fig. 2.—The G35.20 et0al. 2003; seen image insourcecolor overlaid with 11.7 mmemission from Fuller et al. (2001, 2.—The G35.20 as seen at different wavelengths. The 11.7 mm image in color 8.5GHz continuum (black contours; Gibb (a) .74 jet as Gibb at different wavelengths.[0,0], the -band mm imagefalse Fuller overlaid wi the et al. false color defines (a) The K presumed location of et al. (2001 white contours) and the 8.5 GHz high-resolution radio continuum emissionof Gibb strong(2003, gray contours). ((b)) The 18.3 mm image in falsethe overlaid white contours) and the 8.5 GHz high-resolution contours) and theemission high-resolution radio gray contours). b The Gibb et al. (2003, false color overlaid radio continuum 8.5 GHz of et al. (2003, continuum emission of 18.3 in gray contours). (b) white masers (asterisks; Hutawarakorn & Cohen (1988,MNRAS, 303,) 845), water masers (crosses; Forster & color with protostar). OH15 GHz radio continuum image of Heaton & Little 1999, white!"#$%&'"(#)**+ from Fuller et al. (2001, gray contours). ((c)) Zoom & whitecontours) and L iimage contours L mage al. (2001, gray with thethe low-resolution 15 GHz radio continuum image of Heaton 15 Little(1988, continuum image andHeaton &from Fuller et white contours) contoursmage Zoom low-resolution with the low-resolution GHz of Little (1988, and L i ). c from in on the central region of the 11.7339)imagemethanol masersL contours in white and the high-resolution are continuum contours in black. The OH masers C central region of the 213, mm andinin false color, theL contoursradio m image thefalse color, the L radio continuum contours inhigh-resolution masers plus Astrometric black. The in on theaswell 1989, A&A, 11.7 mm image on the central region (large11.7 msigns; Gibb, priv. comm.) radioshown. white and the uncertaintyOHradio c in as false color, the masers of Forster & Caswell (1989) as crosses, contours in masers of A. G. Gibb (2006, private of the in white and in high-resolution and methanol of Hutawarakorn & Cohen (1999) are shown the error water in the lower right. We between & Cohen radio is shown by asterisks, bars of Hutawarakorn MIR and (1999) areshown as asterisks, water Cohen (1999) are shown aspropose as crosses, andof Forster & CaswellA. G. Gibbcrosses, private of Hutawarakorn masers of Forster & Caswell (1989) to use masers methanol masers ofcontinuum (2006, and m asterisks, water ALMA to image 450µm (1989) as and communication) as large plus signs. The bars at lower right& the j relative astrometric uncertainty between the radio for the accretion line emission in a ~9” FOV, resolving structures showthe 11between astrometric 1.5”, especially searching continuum and NIR.disk.between communication) as large plus signs. The bars at lower right as with sizes signs. The 0.23” and uncertainty between1therelativecontinuum and NIR. communication) show plus j relative bars at lower right show the large j radio astrometric uncertainty 18µm continuum (white contours; Fuller et C <.-55D*@6,=*420=+0661*23*@2.,*5+0.*.1+,,+20* al. 2001, ApJ, 555, 125) and high @21+0-=.*=E.*:;<*.1+,,+20*9321*=E+,*,2634.F a G35.2N Outflow Cavity !"#$%& '()#*%+%&,-.% L59 '()#*%+%&,-.% ,%-./012 reaches 20456,+/.*.7-185.* us via the near-side, L59 L59 redshifted CO(3-2) emission !"#$%& Mid IR Emission by Gibb et al. the from 52>?*02=*-*@+,AB approximately following this geometry has been reported D-INFRARED JET OF G35.20 MID-INFRARED JET OF cavity. Blue .74 ID-INFRARED JET OF G35.20 0.74 blueshifted outflow G35.20 0 and 0.74 (De Buizer 2006) a b C <.-55D*@6,=*420=+0661*23*@2.,*5+0.*.1+,,+20* @21+0-=.*=E.*:;<*.1+,,+20*9321*=E+,*,2634.F ,%-./012 a .,*5+0.*.1+,,+20* *9321*=E+,*,2634.F ,%-./012 re 1: The relative simplicity of 2N (adapted from De Buizer ). (a) Left panel: 18µm emission color; Gemini-T-ReCS) overlaid 15GHz emission (contours; on & Little 1988, A&A, 195, 193) ng the bipolar outflow from this ive protostar. MIR light only es us via the near-side, hifted outflow cavity. Blue and ifted CO(3-2) emission oximately following this geometry infrared emission coincident with and immediately north of the to ∼16,000 AU by a B2.6 star. If the dust is made of graphite, infrared emission coincident with and immediately north of the withto ∼16,000 AU by a B2.6 the If the dust is made of graphite infrared emission coincident and immediately north of star. to ∼16,000 AU by a B2.6 een reported by Gibb et al. position of G35.2N demonstrates that the infrared emission here one could heat out to the distance of source 6 with grains having position of G35.2N demonstrates that the infrared emission here position of G35.2N demonstrates onetypical heat out to the distance of one could lower sizehaving that could size of 0.005 here still source 6 with grains the dis the infrared emission mm, 3). The circle shows the 0.1pc is dominated by longer wavelength continuum emission. Therea near the heat out to limit. is dominated by longer wavelength continuum emission. Therea typical size of 0.005 mm, near the size size limit is dominated by longer to be wavelength continuum emission. There- still assumed composition of the a typical lowerof 0.005 m eter fiducial core of MT03 (see fore, the nature of the infrared emission is concluded However, if silicon carbide is the fore, the nature continuum dust emissionthe natureoutflow cavof the infrared emission from the of the infrared However, is silicon get heating the assumed compositioncarbide carbide is fore, is concluded to be emission if concluded to be out much farther silicon of the However, if than source 6, 2a). This also happens to be the predominantly dust, then one can predominantly continuum dust emission from the outflow cavdust, then∼one canAU at the out dust, farther than get heat get heating predominantly continuum dust emission from the outflow cav-0.003 much then size cansource 6 oximate size of the FOV of our ity walls. This cavity was created by the molecular outflow, namely, 52,000 mm lower one limit. There ityoverlaid The 11.7 a image increated ityet al. (2001, walls. with K cavity was false color the(2001, This by al. molecular emission namely, ∼52,000 elengths. (a)The 11.7 m image in false color overlaid with K -band cavity surmolecular at contribution lower size limit. atalnamely, shock heating, th oG35.20 (a0.74 jet 11.7mmmimage in false color which) punchedmmemission from Fuller et walls.with K-bandoutflow, from Fuller et the(2001, of some the 0.003 mmfrom ∼52,000 AUThere sed ALMA The as seen at lengths. et )al.observations. different wavelengths.[0,0], the -band emission from Fuller overlaid This materialwas created bypossibility AUoutflow, holelocation of colormolecular dense is a al. ;ntinuum emission of Gibbstrong(2003, graywhich (a). (b) The 18.3 mm image thedense molecular material surGibb 2003; the et al. presumed in contours is color overlaid al. (2001) claim nois from shock of some c iand the 8.5 GHz high-resolution the continuum emission of Gibb et al. (2003, falsethe overlaid ght panel: Zoom-in towards source defines ). (b The a hole image in gray which punched a hole in the dense molecular material surtinuum emission of Gibb et al. (2003, gray contourspunched 18.3 mstellarthe falseat the center ) The 18.3 mm image in false a possibilityetof some contribution a possibility heating, alin source color overlaid though Fuller detection of shock-excited otar: 11.7µm 1999, MNRAS, radio 845), image from)Fuller et al. (2001, gray & contours). (b rn & & Little (1988, white contours) and L rounding masers young m fsHeatonCohenemission (false 303, and L iwaterfrom the (crosses; Forster contours). ((c)) Zoomof G35.20 0.74. Heaton & Little (1988, continuum image of Heaton & Little (1988, white contours) contours).centerthe G35.20stellar source though(c) Zoomet al. (2001) claim nothough Fullershock-excited contours) mage Fuller et stellar gray rounding the youngal. is mostly and rounding of young 0.74. the c Zoom Fuller at in the of solution 15 GHz radio white!"#$%&'"(#)**+ central source (2001,source atL image from heating al. (2001, gray contours).centerregion. Beaming of the detection of et al. (2001) MIR emission along the The likely directly lor, the L(large plus signs; Gibb, high-resolution are shown. Astrometric uncertainty c white and the priv. comm.) mregion contours in mat 0.35” thefalse color, the Lradio continuum contours inhigh-resolution radio continuum the walls black.HtheOH masers G35.20 0.74. asers of ontours inwhite and in high-resolution radio continuum contours in black. The OH masersFuller et contours in 2 r, Gemini-T-ReCS) m image L black. The OH masers l the masers of11.7 the Forster & and ; directly HThe the heatingBeaming 2 in 2 in emission along the water in the lower right.Caswell (1989) to The ALMA to source 450µmthe G. GibbThe central source found to likely directlyregion. 18µm the isotropic emission assumed in the as use central imagemasers ofcontinuumof the private crosses, contours in white northern likely (2006, outflow was is walls and methanol ofmasers cavity. TheCaswellA. G. Gibbcrosses, private this of Forster &is mostly lobe (2006, andheating the mostlyG. Gibb (2006, privaterather the wallsof theHMIR the region. Beamin outflow axis, than b & Cohen of Forster & We asterisks, crosses, #$%&'"(#)**+are shown aspropose water ater masers n ars the(1999) relativeL’ (1989) of the ution. Superposed are Caswell (1989) as of this and methanol masers of A.and NIR. and outflow was masers of A. lobeoutflow outflow was than the isotropic emission assumed in the cavity. radio continuum and Earth this in methanol found al. axis, rather could to ht show sizes 1 j astrometric 1.5”, especially searching northern lobe as of (i.e., cavity. by Gibb et to uncertainty between the The continuum radio for the accretion disk. The northern of the calculations, found also help in heating grains than th outflow axis, rather farther above be slightlyjblueshifted toward NIR. rtes with plus1contours;0.23” and uncertainty between1therelative astrometric uncertainty betweenCO radio continuum and NIR. between Fuller et show the j relative bars at lower ) as large the nuum (white signs. The astrometric right show the blueshifted toward Earth (i.e., in CO by Gibb et al. be2003; in C i by Little et al. 1998). slightlythis fortuitous ge- Earth (i.e., in CO by Gibb et al. help in derived from the dust slightly above calculations, farther be Given blueshifted toward aboveInterestingly, the MIR luminosity heating grains could out. calculations, could also 01, ApJ, 555, .74 jet and high different wavelengths. C )iThe 11.7 mm et al. in false 2003; in thisi fortuitous et al. 1998). Given (2001,fortuitous ge125) 2003; in (a0.74 by assee directly1998). Given (a) with 11.7asmaimage infrom color et al. this Kgivesemission from Fuller et al. (2001,# the MIR geout. Interestingly, The G35.200.74 jet asas seen at 0 () The 11.7 mm image in false color outflow with K-band emission from Fuller et al. (2001, the MIR luminosityvalue of 1.6 103 dus a canLittle image into the overlaid cavity color overlaid byK-band emission C The Little con- false Fuller overlaid with -band an estimated Interestingly, out. derived from L,. he G35.20 of seen at 16,000 AU by a B2.6 star. If the at different Fig. 2.—The ometry, we jet m color temperature tely to ∼ different wavelengths. emission of seen al. madegray graphite, b The 18.3 mm of contours ution 8.5GHz continuum (black contours;G35.20westar. If the dust is intowavelengths.[0,0], )the presumedimage in false color Gibb the defines tours)north 8.5 the withto ∼16,000radio ometry, emission of Gibbdust is(2003, gray outflow).cavitysee a dustlocationthe the overlaid gives conly andcoincident high-resolution AU continuumof al. 2003;clearing away the material ). ((b) The 18.3 met al.is into Assuming the(MIR as a mm image in the luminosity of the source north of 8.5 GHz and white radio continuum et of seeGibbstrong sourceometry, emission If Gibb con- madeof contours b) The 18.3 an estimated value of 1.6 103 L an the a the directly(2003, ofof contours along the m image gray graphite, ssion and the here high-resolution contoursby to B2.6 the theof to ∼etal.6 with grainsahavingstar. ofas directly(2003,coloroutflow).cavity luminosity is all color color overlaid #gives , immediatelysequence can high-resolution madecontinuum we can our line of in false color overlaid north 8.5 GHz 16,000 AU bygraphite, B2.6 of temperature rs)emission GHz the et ) and the distance radio 845), water masers (crosses; Forster & false temperature d one could imageout heat star). OH masers (asterisks; Hutawarakorn & Cohen 1999, source 303,) MNRAS, w-resolution here radio continuum image out Heaton & Little (1988,white!"#$%&'"(#)**+ from Fuller et al. (2001, gray contours). ((c)) Zoom white contours -resolution 1515 GHz radio continuum heat ofofsight &distanceclearing contoursofandHeaton &distanceclearingof 6 withcontoursmage ZoomFuller etline of iscalculating ). (cthe MIR luminos L having emission GHz could to the ontours source 6 away ) outL i mage LittleFuller 35.2N demonstrates oneimageinfraredsequence15mm, (1988,white couldimageandcomm.) radio continuumal. (2001, in black.materialthe MIRour al. (2001, gray Assuming ) Zoom the source the methanol Heaton of the of one Gibb, priv.material along (1988, line away of L i ). c from emission Little radio continuum with grainsimage fromtheouret contours gray Assuming along luminosity all the luminosity of grains having with contours a spectral (an obvious underestimate) and central region of the 11.7339)typical false color, the by cthe outflow itself.the high-resolution are shown. Astrometric uncertainty mm ell region of the 213, that andinthe low-resolution chere pluswhite and in lowersequence of continuumwhite contours) andThe OH masers masers ontours in near the heat of size limit. mission. A&A, 11.7 mmaimage onin size of regionL(large11.7inmsigns;andthefalse color,to the contours inof source the high-resolution radio continuum contours in black. The OH masers type from 0.005 GHz tral 1989, Therefalseemission.L them, still mitself. color, 0.005 of the still a image the Therehigh-resolutionL m contours in the 0 ission. Therea continuum of by m of Forster &typical (1989) of use limit. methanol sources lower size limit. typical asterisks, the size as crosses,the outflow itself. (an obvious underestimate) by MIR Cohen be isareHowever,size sightThe sources fartherCaswell lowersight byradiom, imagenear theA. G.(an obvious underestimate) and calculating a spectral type from longer to radio shown by theiferror water in the lower right. We propose tosize of .74, namely, masers ofcontinuum (2006, private luminosity using the method from De Buizer wavelength shown as the centralbars masers outflownearnorth of G35.20 ALMA to stillwhite and in black. The OH masers 0.005 and that and rakorn Gibb bolometric een & and (1999) oncluded silicon Cohen of korn & Cohen (1999) are shown as asterisks, watercarbide is the assumed asterisks,as crosses,the of Forster & CaswellA. G. Gibbcrosses, private masers & and masers of of Hutawarakorn show the(1999) relativeCaswell (1989) watercarbide methanolsources (1989) as (2006, and are shown as composition sources radio 450µm ncludedin plus the method with ation)of the infrared However, lower right&carbide is farther north composition of the searching continuum G35.20 of the methanol masers of A. G.that (2006, private the radioThe bars at if concluded toexpectedassumed of ofuncertainty .74, is farther for the of that bolometric luminosity of astrometric tureoutflowplus signs. The barsthenis silicon getaresizes Forstermuch farther 1.5”, Themasersnamely, assumed composition 0.74, gives a sources ∼B3, Gibbbolometric De Buizer 5–9, the be jthe However, silicon between the itself and NIR. m as to be resolving one canshow heating jout to astrometricG35.20eitherthe the radio north accretion disk. on) as large a ~9” FOV,dust, at structures with plus1 signs. The 0.23” and than especiallythejoutflow astrometric uncertainty between the radio continuum relative bars at lowerdust source in NIR. theissionlargecav- signs. emissionlower rightThe sources1between be knots if uncertainty0between1therelativecontinuum and et al. (2005) namely, value usingand consistentfrom luminosity 6, communication) as large right show NIR. 11.7µm 2 b 2 2 18µm 6,=*420=+0661*23*@2.,*5+0.*.1+,,+20* Rotation and =.*=E.*:;<*.1+,,+20*9321*=E+,*,2634.F outflow axis inclined at 60˚ e continuum dust dust, then∼one canAU at the preexisting farther than source 6, outflow upon consistent gives a value 5–9, clumps of to mm knots one can get in the are expected be 5–9, ly outflow cavthan (2005) gives a value of derived spectral lecular outflow, emission from the outflow cav-0.003 much thenof dust either being impingeditself of dust either in 6, outflow itself ∼B3,et al. (2005)with the radionamely, 52,000orget heating out dust, material that are heating out much farther et al. source the type. In summary, all of the dust, even as far limit.are expected to be knots cular outflow, of sight. 52,000 bysomeoutflow. Sourcelower 52,000 are being impingedm lower size limit. sourceimpinged upon be heated directly bytype.as far namely, ∼ molecular outflow, AU at contribution from ∼ size or AUatal- 0.003 m upon all of the dust, G35.2N, tcavitycoincident withaand immediatelythe ofof0.003 mmtolower size AUAUThere G35.2Nthe dust is made of graphite, type. indeed o line of that are There is materialwas created bypossibilityor clumpsthe preexisting material that clumpsthe preexisting materialderived spectral6, can In summary, derived spectral even In su the namely, shock limit. There out as being 6 16,000 heating, from star. If and is lies 19,200 by a B2.6 ar is of north the emission sur∼ ission coincident dense infrared emissionat an claim nois dust16,000shock-excited G35.2N the6∼is is madeas source G35.2N indeed be madeasdirectly by can inde north of material in possibilitybyal. (2001) the with fromcolor temperatureal- the If and is16,000out of graphite, lies of AU the out a hole molecular material surof some of and shock heating,theof star. AU by on graphite, depending alstill coincident detection19,200 by from distance This lies fedG35.2N 0.74. with athatimmediatelyemissionestimated to possibility byoutnorthcontribution to dustshock heating,B2.6dust composition is heatedof source as beaming), G35.20 sur- the is and the infrared some contribution a6 ∼ could heat AUto B2.6 112 K.of source 6 with grainsahavingstar. If the dust and size (as well 6, G35.2N though Fuller etof the outflow. Source one immediately aoutflow. Source from 19,200 AU from 6, can and is of m = demonstrates here 8 G35.2N demonstrates thatcenterregion.emissionclaim no detection ofheat al. (2001) claimK. dust couldtemperature on dust composition anddepending on as compos here one could shock-excited of no source G35.20stellar source thoughthe infraredbasedan0estimated thoughthe infrared emissiondistance of onecolorofheatgrains having K. ofout is 6 with grains well dust possible 0wallsM!at the the ofet al. Beaming of11.7 and 18.3 mmet outat anof 112 this detection depending of 112 rule source .74. Fuller still at (2001) the size from other still 0.005 young* longer wavelength continuumG35.2N onThere- the dust typicaltemperaturetheestimated This is the with out to the distance This contributions(as having beaming) .74. Fuller flux to shock-excited position ofG35.20 demonstratesMIRcolor size along the here still source 6 lower size limit. that emission ofdensitiesmm, though we cannot eating the H in ated by emission. a near ed waslonger to likely3 continuum basedlonger wavelengthin effectsfluxsilicatethe 11.7 (see18.3 mmlowerof we limit. rule out by typical ting the walls H is the heatingBeaming 11.7 possible emission along the of still MIR on 18.3 m ifof though we other the flux size cannot source foundwavelengthin dominatedandthan There- theHMIR the massumed 0.005 of is the source thecomposition the m this source the lower fromcannot rule ou mostly continuum based incarbide the assumed size densities of still near emission. absorption a typical though 0.005 heating mechanisms. De wnatureisof the infrared directlyregion.bythe wallsisotropicaemissionregion.ofBeamingmm,thisandnear emission along of the m,450µm contributionssize limit. possible outflow axis, isemission. the of and However,size densities 18µm the emission rather neglects the concluded to be siliconon ThereLbol = 6 above outflowconcludedthe cav-a) Left: AnalyticifCorecanfartherto isotropicmuch starthan discussed is the L axis, and could 2: ( outflow axis, grainsAccretion Model(seeemission heatingsource 6, ature found al. lobeoutflow calculations, thanet to the helpfor method assumed in absorptionis assumed compositioncarbide in § (see De composition of the of et infrared emission is nature foundal.isotropic However, ofsilicon get heating the However, if silicate of the be emission and carbide is silicate De of As y.wasGibbtheto x10emissionthe rather neglectsalso possible heatingandconcludedthe Whatoutheating farther siliconin absorption 3.1, MIR source 3, coincident with NIR The continuum dustof the ! fromwas outflowtoinfrared in effects israther neglects the possible effectsassumed mechanisms. assumed heating mechanisms. northern the fore, of Buizer [2005] emission one thanthe be limitations). by nantly the Figure dust, then of massive formation 0.74 ntly continuum emission the molecularMIRcav- help dust, then∼from could cav- isfor dust, fartherlimitations). can can than get heating heating calculations, continuum 3, source method from the dustoutflow, Smaller grains AU heating lueshifted toward createdInterestingly, Gibb al. al. far out?in heating one grainset at Whathelp outheating size canfarther 6,in out much sourcethancoincidentin § 3.1, M by could [2005] emission and Buizer dust the out m lower As discussed s fortuitous ge- dust above by from the outflow alsodust above calculations,outflow be heated inm tothen one collapsing the presumed infrared southern6, with NIR out. predominantly theet etthis& for methodfromlimitations). [2005] heating andemission There s.by Gibb et al.wasEarth (i.e., in CO Buizer McKee luminosity deriveddustthe theget al.also 0.003 much! coregrains source What§is3.1, MIRfarther As discussed counterjet, This cavity namely, 52,000 farther ( 60M is limit. This Little etwas created itytemperature the MIRwas out? 2003; Zhang1.6 #of 3some the fiducial mmfrom ∼52,000not havethesmoothlym lower size limit. There the presu by the molecular this luminosity derived molecular MIR far0.003 namely, shock limit. from 0.003 m to namely,dust & TanAUoutflow, ∼ grains Lthis at fortuitous con- thecolor walls. the dust outflow, Tanout.valuethe 52,000theThe . contribution derived emission dust the presumed infrared southern typical of out. Interestingly, material far createdlarge dustfrom 102011). Aheated out to Smaller of grains. can be out? range does AU at farther geemission slope the iunched aa hole in1998). Given this Thisgivesdistances thanis Interestingly,37!m typical sizeSmaller dust grains can beaheated out increasing spectralfrom counterjet by cavitygeal. fortuitous an surfrom the There cavity estimated bypossibility dustdust luminosity lower size heating, alcavity as dense molecular from the inside-out, via an expansion wave, rotating supersonic infall region and accretion disk. The outflow cavity is shown a 3, 3 What are the pressures where massive stars form? Massive Star Formation Theory Turbulent Core Model (McKee & Tan 2003) Star Cluster Formation Theory AV=200 A8!m=8.1 NH=4.2x1023cm-2 5cm-3 nH~2x10 GMC Evolution & =4800 M pc-2 ! ! Equilibrium Star Cluster Formation (Tan et al. 2006) tff~1x105yr SFR Theory GMC Collision Model (Tan 2000) AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 Overview of Physical Scales From Local Regions to Extreme Starbursts AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 Galactic Disk !~10 M! pc-2 Overview of Physical Scales From Local Regions to Extreme Starbursts Star Formation Near Supermassive Black Holes ULIRG GMCs? AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 ULIRG disks (Downes & Solomon 98) Galactic Disk AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 !~10 M! pc-2 The First Stars Definitions McKee & Tan (2008); O’Shea et al. (2008; First Stars III Conference Summary) Population III Stars having a metallicity so low (Z<Zcrit) it has no effect on their formation, i.e. negligible cooling (~10-5Z!), or their evolution (~10-8Z!). Population III.1 The initial conditions for the formation of Population III.1 stars (halos) are determined solely by cosmological fluctuations. Population III.2 The initial conditions for the formation of Population III.2 stars (halos) are significantly affected by other astrophysical sources (external to their halo). .) t al re ne rs J. Tur la egu icky, irr arf obuln w in d on, K s Cs SS John (K. nH~2x105cm-3 tff~1x105yr Overview of Physical Scales AV=200 A8!m=8.1 NH=4.2x1023cm-2 !=4800 M! pc-2 p Po AV=7.5 A8!m=0.30 NH=1.6x1022cm-2 !=180 M! pc-2 1( III. 1) K’= AV=1.4 NH=3.0x1021cm-2 !=34 M! pc-2 re co Some Current & Forthcoming Observatational Facilties GTC-Canaricam FLAMINGOS-2 Herschel SOFIA E-VLA ALMA JWST, TMT, SPICA GAIA, SIM Some ideas for open projects • • • • • • • • Kinematics of star clusters Low-Surface Brightness galaxies Circumnuclear starbursts Galactic Center Star Formation Dark Matter Powered First Stars Herschel Hi-Gal Analysis SOFIA studies of massive star formation Astrochemical models of massive star formation • ... ...
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This note was uploaded on 01/22/2012 for the course AST 1022l taught by Professor Colon during the Fall '07 term at University of Florida.

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