21 November 2002Millimetre Workshop 2002, ATNF First ATCA results at millimetre wavelengths Vincent Minier School of Physics University of New South Wales

Narrabri, NSW, 500 km NW from Sydney; 6 antennas, 22-m diameter, baselines 31 m to 6 km; Traditional frequency range: 1 – 10 GHz (20, 13, 6 and 3 cm or L, S, C, X) Upgrade of ATCA at 3 and 12 mm :  85 – 110 GHz (5 antennas)  16 – 26 GHz (full array) Australia Telescope Compact Array

ATCA site E-W track S-N spur Control room Mm receivers

First light on 30 th Nov Orion SiO GHz

ATCA at 3 & 12 mm – Current Status 3 mm system 3 mm system  Frequency range: (1) GHz (2) GHz  3 baselines, 2 pol.: CA02, CA03, CA04  System temperature: 250 – 400 K  Bandwidth: 64, 128 MHz, spectral res. = 0.86 km/s  Sensitivity in 1 hr: 3.6 mJy (cont.) and 96 mJy (line) 12 mm system 12 mm system  Frequency range: GHz  15 baselines, 2 pol.: CA01, CA02, CA03, CA04, CA05, CA06  System temperature: 60 – 70 K  Sensitivity in 1 hr: 20 mJy (line) with 16 MHz and 512 channels

GHzSiO 2-1 v=1 (maser) 85-87CH 3 OH (maser+thermal) SiO 2-1 v=0 (thermal) HCN HCO GHzH 2 O maser 23 to 25NH 3 What can we observe with ATCA-mm? Molecular lines: Continuum emission: dust (3 mm) and ionised gas (22 GHz)

Recent Results at 3 and 12 mm  Pre-planetary disks around young stars (Wilner, Bourke, Wright, Jorgensen, van Dishoeck, Wong in 2002)  Massive star formation in the Galactic Plane (Minier, Burton, Wong, Purcell, Hill, Hunt, Barnes, Jones, Ellingsen, Cragg, Sobolev, Voronkov in 2002 – 2003)  Massive star formation in the LMC (N113: Wong, Ott, Mizuno et al. in 2001 – 2003; Water masers: Beasley, Claussen, Marvel & Staveley-Smith in 2002)

1.Pre-planetary disks around young stars

Dust in Pre-planetary Disks (Wilner et al in press) TW Hya T Tauri star 41±4 mJy HD Herbig Be star 36±3 mJy 3.4 mm continuum emission  dust emission from disks 2 ATCA runs  6 baselines (2’’= 100/200 AU) See poster by Bourke et al.

2. Massive star formation in the Galactic Plane

Methanol masers = massive YSOs ? CO Dame et al IRAS 100  m IRAS Masers SIMBA 1.2 mm 240 M  (Hill et al. in prep; Walsh et al. 1998) Maser UCH II ATCA 3 mm 15 M  (Minier et al. in prep)

Unresolved CH 3 OH core < 0.04 pc Resolved HCO + core: R=0.06 pc  =33 N H2 =5.5  cm -2 M gas =15 M  M vir =120 M  Resolved HCO + wings  outflows. Massive protostellar core A hot molecular core in G Posters by Tracey Hill et al., Cormac Purcell et al., Peter Barnes et al. and Vincent Minier et al. Res.: 4 – 22’’ = 0.04 – 0.26 pc HCO + Hot core CH 3 OH

Methanol masers in G GHz maser 86.9 GHz maser All masers coincide in velocity and position  coincide in space (Minier et al. in 2002) UC HII region Masers

Probing gas/dust conditions with methanol masers Ellingsen et al. 2003, in press  Using model by Cragg et al. (2001).  Hot dust: K  Cold gas <50 K  Density: 10 6 cm -3

25 GHz methanol maser in Orion BN/KL (Voronkov et al. in 2003) E

Deuterated ammonia in NGC 6334 I(N) (Wong, Minier & Forster in 2003) Burton et al GHz NH 2 D EW and 86 GHz Continuum + NH 2 D

3. Massive star formation in the LMC

HCO + core in N113  For a virialized cloud, ignoring optical depth effects, M  200(R pc )(  v km/s ) 2  5000 M .  For constant density, n H ~ 5 x 10 4 cm -3. FWHM  1.5 pc  R ~ 1 pc.  v ~ 5 km s -1. ( Wong et al. in )

Previous Parkes detections ( Scalise & Braz 1982 ; Whiteoak et al. 1983; Whiteoak& Gardner 1986) New ATCA detections New water maser sites in the LMC (Beasley, Claussen, Marvel & Staveley-Smith 2002)

Conclusions 12 mm system is fully operational and works well; 3 mm upgrade on its way and expected to be complete for next winter (May 2004?); 3/12 mm results since 2002: 43 projects of which 27 in star formation; Next observing session: mid-April to mid-Oct. (or mid-Nov. depending on the configuration) NEXT PROPOSAL DEADLINES : Oct. 15 th, Feb. 15 th, June 15 th (might change to 6 month-observing terms)

3 mm user guide web page: 12 mm system web page :

Phase stability Clear Night, 8pm local time 45m75m120m  rms :22º 34º19º b:

4 hours later (midnight) 45m75m120m  rms :22º 34º19º b:  rms :16º 24º13º