# High-Mass Star-Forming Regions in the G333 Cloud Indra Bains & the DQS team.

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High-Mass Star-Forming Regions in the G333 Cloud Indra Bains & the DQS team

A B C D E

Source A CO channel maps 12 CO contours, 13 CO greyscale

* MSX source H2O maser OH maser HII region 1.2 mm source IRAS error ellipse Absorption features Self-absorbed 12 CO 13 CO CS SiO A

Source C molecular outflow 12 CO CS * MSX source H2O maser OH maser star CH3OH maser 1.2 mm source IRAS error ellipse CS

Source D molecular outflow * MSX source OH maser 1.2 mm source IRAS error ellipse 12 CO CS

Outflow analysis T 13 > 5 , T 12 > 5 , T 12 /T 13 > 1: –T 12 /T 13 = 1-e  13 /1-e  13  12 =  13  = 45 –  12 = 15-130 –Calculate Tex ( 12 CO); N 12 assuming all levels thermalised etc T 13 > 5 , T 12 > 5 , T 12 /T 13 5 , T 12 < 5  : –N 13 in optically thin limit, Tex=7.5 K T 12 > 5 , T 13 < 5 , (eg wings, larger spatial offsets) –  12 = 15, calculate Tex( 12 CO), N 12 M(x,y,v) = m mol N H2 V(x,y,v) N H2 = XN CO d=3.6 kpc

Outflow properties Source C: M out = 5.5e3 Mo (M 1.2mm = 7.2e3 Mo Mookerjea et al 2004) Source D: M out = 2.1e3 Mo (M 1.2mm = 5.5e3 Mo) KE ~ 10^49 erg

ATCA observations Freq (MHz) typical beam (``x``) mode 1384 14.10 x 8.90 c 2368 8.37 x 5.22 c 4800 4.37 x 2.23 c 8640 2.36 x 1.22 c 22369 0.83 x 0.58 RRL + c 89209 2.16 x 1.75 HCO + + c

Source C radio continuum 1384 MHz 2368 MHz 4800 MHz 8640 MHz

Source C SED  = 1.2 22 GHz89 GHz

Source C properties 3 mm dust mass lower limit 6.6e3 Mo (T d = 40 K), 1.4e4 Mo (T d = 20 K) c.f. 1.2 mm mass 4.6e3 Mo (T d = 40 K; Mookerjea et al 2004) 22 GHz deconvolved size 0.02 pc Assuming  22GHz << 1 (lower limit): –N i = 4.4e48 s -1 ; 1 ZAMS O7 (Panagia 1973) –EM = 1.4e9 pc cm -6 –n e = 2.4e5 cm -3 –M ion = 0.03 Mo Assuming v exp = c s ~ 11.4 km s -1 t = 1e3 yr UCHII region

2368 MHz 1384 MHz 4800 MHz 2368 MHz 8640 MHz Source D radio continuum

 2368 1384 = 3.0  8640 4800 = 0.6 Source D SED 22GHz89 GHz

Source D properties 3 mm dust mass lower limit 2.1e3 Mo (T d = 40 K), 4.4e3 Mo (T d = 20 K) c.f. 1.2 mm mass 5.5e3 Mo (T d = 40 K; Mookerjea et al 2004) 22 GHz deconvolved size 0.03 pc Assuming  22GHz << 1 & within resolution effects: –N i = 5.7e48 s -1 ; 1 ZAMS O6.5 (Panagia 1973) –EM = 1.4e9 pc cm -6 –n e = 2.1e5 cm -3 –M ion = 0.1 Mo UCHII region

Summary G333 cloud contains massive bipolar outflows with HII regions in the centre Line modelling NANTEN2 observations of higher J transitions ATCA HCO + data Obtaining 2 more RRLs to solve for broadening terms, hence T e, n e etc in HII regions

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