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Millimetre ATCA Results
Vincent Minier
School of Physics UNSW

21 November 2002

Millimetre Workshop 2002, ATNF


ATCA at 3 & 12 mm ­ Current Status
3 mm system
! Frequency range: (1) 84.906-87.305 GHz (2) 88.506-91.305 GHz ! 3 baselines, 2 pol.: CA02, CA03, CA04 ! System temperature: 250 ­ 400 K ! Bandwidth : 128 MHz

12 mm system
! Frequency range: 16-26 GHz (no tuning needed !) ! 15 baselines, 2 pol.: CA01, CA02, CA03, CA04, CA05, CA06 ! System temperature: 60 ­ 70 K


First light on 30

th

Nov. 2000

Orion SiO 86.243 GHz


Recent Results at 3 and 12 mm
Wright, Jorgensen, van Dishoeck, Wong, 2002)

" Pre-planetary disks around young stars
(Minier, Lineweaver, Burton, Purcell, Longmore, Norris, 2003)

(Wilner, Bourke,

" Planetary water masers in extra-solar systems " Search for biomolecules in Sgr B2
Burton, Wong, Purcell, Hill, Longmore, Barnes, 2002 ­ 2003) (Jones, Hunt, 2002) (Minier,

" Massive star formation in the Galactic Plane " Late-type stars (AGB, CSE, SiO masers)
Lindqvist, Wong, 2002)

(Olofsson,

" Massive star formation in the LMC " SNR1987
(Manchester et al. 2002)

(N113: Wong, Ott, Mizuno et al., 2000 ­ 2002; Water vapour masers: Beasley, Claussen, Marvel & Staveley-Smith)

" Molecular gas in nearby galaxies

(Koribalski et al. 2001)


1. Pre-planetary disks around young stars



Dust in Pre-planetary Disks
D. Wilner et al., submitted

TW Hya T Tauri star 41±4 mJy

HD 100546 Herbig Be star 36±3 mJy


2. Planetary water masers in extra-solar systems


Water vapour masers in giant planet atmospheres
HST, 336 nm

Io

C

AE
th

Shoemaker-Levy 9 collision: 17

July 1994 Cosmovici et al. 1996

!September 2002, Cosmovici et al. announced the detection of water masers in 4 exo-planetary systems (e.g. Eps. Eridani). !December 2002, the detections were not re-confirmed with the VLA despite a sensitivity of a few mJy/beam.


Search for water masers toward very young "solar systems" (1-2 Gyr)
12 mm system
! Frequency range: 22.23508 GHz ! EW352+antenna 6 #15 baselines, 2 pol.: CA01, CA02, CA03, CA04, CA05, CA06 ! Tsys & sensitivity: 60 ­ 70 K 20-40 mJy Maser?


3. Search for biomolecules in Sgr B2


Search for glycine (87 GHz) and propylene oxide (86.7 GHz)
Propylene oxide HCO+

Unknown line

No detection down to 30 mJy/beam.
Glycine


4. Massive star formation in the Galactic Plane


Galactic plane
Opt FIR

Methanol masers as tracers of massive star formation
Dame et al. 2001

CO


G318.95-0.20 (IRAS 14567-5846)
ATCA at 6.7 and 8.6 GHz

UC HII +MSX/mid-IR Methanol maser + MSX/mid-IR

IRAS source is resolved in 2 cores


G318.95-0.20 (IRAS 14567-5846)
! HCN, HCO+(Mopra); H13CO+, HC3N, CH3OH: all dense gas tracers (>105 cm-3). ! ATCA-3mm + EW214 (6 ­ 20 arcsec). ! 750A # resolved out or large phase errors on long baselines ! EW352 (bad weather) ! RMS=80-100 mJy/beam EW214


Averaged spectra
H13CO+ HCO+

CH3OH

HCN


Cross-correlated spectra
H13CO+ HCO+

CH3OH

HCN


G318.95-0.20 (IRAS 14567-5846)
HCO+
Core?

60 m

90 m

Extended emission?

Wing

30 m


G318.95-0.20 (IRAS 14567-5846)
! The methanol masers in G318.95-0.20 coincide with a dense molecular core. ! HCO+ bipolar structure = molecular outflows. ! No UC HII region is detected.

! G318.95-0.20 = a massive protostar?
! CH3OH, HCO+ # Mvir= 126(Rpc)(vkm/s)2= 120 ­ 400 M ! ngas= 6 x 107 cm-3

!


Methanol masers in G345.01+1.79
85.5 GHz

86.9 GHz

All masers coincide in velocity and position # coincide in space


Probing gas/dust conditions with methanol masers
! Using model by Cragg et al. (2001). ! Hot gas 200-300 K ! Cold dust <50 K ! As expected for a massive protostellar core.

Ellingsen et al. 2003, accepted in MNRAS


Water masers in MSF regions
G345.01+1.79


NH3 emission (23.7 GHz)
Orion KL


5. Late-type stars


Circumstellar Shell Around R Scl
! R Sculptoris has been inferred from SEST CO (3-2) observations to have a 10"-radius detached shell (Olofsson+ 1996). ! Also, a dust shell with radius ~20" is seen in polarised scattered light (GonzАlez Delgado et al 2003).


No shell emission (3 = 75 mJy)


AGB star IRC+10216
HCN C3N(9-8)

BIMA images

ATCA July 2001 30m baseline 2 pol. uncalibrated
HNC SiS(5-4)


6. Massive star formation in the LMC


HCO+/HCN in N113

Chin et al. 1997

! SEST 58" beam ! Tmb(HCO+) 0.6 K ! Flux 15 Jy
Fukui et al. 2001


2002 Observations
90m

135m

45m


HCO+ contours over DSS image
FWHM 1.5 pc R ~ 1 pc.

v ~ 5 km s-1.

!For a virialized cloud, ignoring optical depth effects, M 200(Rpc)(vkm/s)2 5000 M". !For constant density, nH ~ 5 x 104 cm-3.


Previous Parkes detections
(Scalise & Braz 1982; Whiteoak et al. 1983; Whiteoak & Gardner 1986)

New ATCA detections

22 GHz water masers in LMC


7. SNR 1987


12 mm continuum in SNR 1987
19 GHz continuum 3 baselines (max: 2 km)


8. Molecular gas in nearby galaxies


The radio galaxy Centaurus A
HCO+ absorption in Centaurus A HCO+ absorption in Centaurus A Observing parameters ! 2 IFs: BW= 64 MHz 128 channels, each ! IF1: 89.010 GHz IF2: 90.485 GHz ! velocity range: 500 680 km/s
SEST

(Wiklind & Combes 1997)

! EW352: 45, 75, 120m
Wiklind & Combes 1997


HCO

+

HNC


The Circinus Galaxy
10 July 2001 30m baseline HCO+(1-0) Tsys about 350 K 2IFs, 128 MHz BW, 64 channels each ! IF 1: 89.110 GHz ! IF 2: 89.020 GHz ! ! ! ! !

IF1

IF2

40 min


Recent Results at 3 and 12 mm
Wright, Jorgensen, van Dishoeck, Wong, 2002)

" Pre-planetary disks around young stars
(Minier, Lineweaver, Burton, Purcell, Longmore, Norris, 2003)

(Wilner, Bourke,

" Planetary water masers in extra-solar systems " Search for biomolecules in Sgr B2 "
Burton, Wong, Purcell, Hill, Longmore, Barnes, 2002 ­ 2003)

NEXT PROPOSAL Massive star formation in the Galactic Pl DEADLINE : JUNE 15
th

(Jones, Hunt, 2002)

ane

(Minier,

" Late-type stars (AGB, CSE, SiO masers)
Lindqvist, Wong, 2002)

(Olofsson,

" Massive star formation in the LMC " SNR1987
(Manchester et al. 2002)

(N113: Wong, Ott, Mizuno et al., 2000 ­ 2002; Water vapour masers: Beasley, Claussen, Marvel & Staveley-Smith)

" Molecular gas in nearby galaxies

(Koribalski et al. 2001)