submillimeter observations of high-mass star formation › sci › meetings › 2010 ›...

submillimeter observations of high-mass star formation

spectral surveys with JCMT & Herschel

Matthijs van der Wiel (Kapteyn & SRON, Groningen, NL)Floris van der Tak (SRON), Marco Spaans (Kapteyn)

JCMT/SLS team [Gary Fuller et al.]Herschel/CHESS team [Cecilia Ceccarelli et al.]pi

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edit:

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Matthijs van der Wiel (Kapteyn & SRON, Groningen) 2010-11-19, Herschel-ALMA conference, Garching, slide

intro: high-mass star formation

2

Crab Nebula (Hubble Space Telescope)



2

• impact of high-mass stars:

• UV radiation ionizes

• SNe enrich the ISM, and provide mechanical energy

• strong stellar winds



(figure:

Wilfred Friesw

ijk)


2





• HMSF challenging to study:

• short timescales (~105 yr)

• dust obscuration

• IMF slope

• clustered nature

➡ large distance, rare, crowded



(figure:

Wilfred Friesw

ijk)


2





• HMSF challenging to study:

• short timescales (~105 yr)

• dust obscuration

• IMF slope

• clustered nature

➡ large distance, rare, crowded

✴ Accretion dynamics in HMSF?


Matthijs van der Wiel (Kapteyn & SRON, Groningen) 2010-11-19, Herschel-ALMA conference, Garching, slide 3

intro: AFGL2591


• isolated HMSF regionat ~1 kpc distance

3

MSX 8 micron

intro: AFGL2591



• central core: 200 AU, T>300 K

3

(Subaru 25 micron, De Wit et al. 2009)

intro: AFGL2591




• envelope of gas & dust:size of few 104 AUT down to ~20 K

3

SCUBA 850 micron(Jennifer Williams)

20 kAU

intro: AFGL2591





• molecular outflows

3


20 kAU

intro: AFGL2591






• IR bright: 2×104 Lsun

3


20 kAU

intro: AFGL2591






• IR bright: 2×104 Lsun

• density n∝r-α

α=1.0-1.5H2 density 104-107 cm-3

3


20 kAU

intro: AFGL2591


goals & methods

4

goals methods


goals & methods

1. investigate physical structure of molecular gas around protostardistribution of envelope material gives constraints on accretion mechanism

4

goals methods


goals & methods


2. determine molecular excitation conditionsconstrains heating mechanism

4

goals methods


goals & methods



4

• spectral imaging with multipixel HARP-B spectrograph at 15-m JCMT (Hawai’i)330-373 GHz // 800-900 μm

James C

lerk

Maxwell Tele

scope

(JCMT)

goals methods


JCMT spectral imaging

5


• Spectral Legacy Survey (SLS): spectral imaging330-373 GHz (~800-900 micron, ALMA band 7) resolution 15” (15 kAU), 1 MHz (~ 1 km/s)


5



• 35 resolved maps, 12 molecular species


5





5

2 arcmin = 120 kAU





5

2 arcmin =

120 kAU

13CO 3-2velocity bins

← blue center

red →




• conclusions:

• non-circulare structure

• velocity gradient

• bulk of emission traces quiescent envelope


5

2 arcmin =

120 kAU

13CO 3-2velocity bins

← blue center

red →


simple model descriptions


• radiative transfer modeling (RATRAN)for HCN, C17O, HCO+, H13CO+, CS, C34S

6




• three physical descriptions for envelope:

6





1. spherical static

6





1. spherical static

6


observed long axisobserved short axismodeled intensity




1. spherical static

2. spherical infalling

6






1. spherical static

2. spherical infalling

3. flattened static

6




−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)

modeled velocity profiles


• line profile in velocity space never fits in optically thick case

7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)




7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3 1D static model

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)




7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3 1D static modelinfall model

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)




7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3 1D static modelinfall modelflat model at i=20◦

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)




• infall model most discrepanteven in thin tracer

7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)





• conclusion: static models work for optically thin lines, not for optically thick lines

7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)






• need to model detailed distribution of molecular gas

7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(thick)

(thin)







7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(!) open door: ALMA

(thick)

(thin)


ALMA synthesized beam






7

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)

HCO+ 4–3

−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

−20 −15 −10 −5 0 50

5

10

15

20

25

30

T mb

(K)


−20 −15 −10 −5 0 5Vlsr (km s−1)

0.0

0.5

1.0

1.5

2.0

T mb

(K)

H13CO+ 4–3

(!) open door: ALMA

need mosaic

mode

(thick)

(thin)


ALMA synthesized beam


side step: chemical census

8

Frequency (GHz) →


side step: chemical census

8

• full 330-373 GHz spectrum: ~160 lines

• chemical inventory >20 species

Frequency (GHz) →



• broad range of energy levels(100-300 K) multiple molecules

• HIFI instrument on Herschel490-1900 GHz // 610-158 μm

back to goals & methods

9

goals methods

James C

lerk

Maxwell Tele

scope

(JCMT)







9

goals methods

James C

lerk

Maxwell Tele

scope

(JCMT)








9

goals methods


13CO

5-4

J=11-10

6-5

7-6

8-7

9-8

10-9

Herschel/HIFI spectral scan

10

• CHESS key program:490-1240 GHz surveyresolution: 0.7-0.3 km/s

• high-J lines of HCN, HNC, CS, HCO+, CO


13CO

5-4

J=11-10

6-5

7-6

8-7

9-8

10-9


10



HCN

6-5

7-6

8-7

10-9

J=11-10


13CO

5-4

J=11-10

6-5

7-6

8-7

9-8

10-9


10



HCN

6-5

7-6

8-7

10-9

J=11-10HCO+

J=12-11

6-5

7-6

8-7

10-9

11-10


13CO

5-4

J=11-10

6-5

7-6

8-7

9-8

10-9


10



HCN

6-5

7-6

8-7

10-9

J=11-10HCO+

J=12-11

6-5

7-6

8-7

10-9

11-10

50 100 150 200 250 300 350Eup/k (K)

0

50

100

150

200

�T m

bdV

(Kkm

s−1 )

HCN (x 50)HCO+ (x 10)CS (x 50)13CO

C18O (x 10)

C17O (x 20)


13CO

5-4

J=11-10

6-5

7-6

8-7

9-8

10-9


10



HCN

6-5

7-6

8-7

10-9

J=11-10HCO+

J=12-11

6-5

7-6

8-7

10-9

11-10

50 100 150 200 250 300 350Eup/k (K)

0

50

100

150

200

�T m

bdV

(Kkm

s−1 )

HCN (x 50)HCO+ (x 10)CS (x 50)13CO

C18O (x 10)

C17O (x 20)

←compare this to model SLED


HCO+

J=12-11

6-5

7-6

8-7

10-9

11-10

velocity shift with energy

11

JCMT beam →


velocity shift with energy• higher Eup:

velocity shifts to red

11

JCMT beam →

0 50 100 150 200 250 300 350Eup/k (K)

−6.0

−5.5

−5.0

−4.5

−4.0

V cen

troi

d(k

ms−

1 )

HCNHCO+

CS13CO

C18O

C17O




• also smaller beam…HPBW 44”→20”

11

JCMT beam →

0 50 100 150 200 250 300 350Eup/k (K)

−6.0

−5.5

−5.0

−4.5

−4.0

V cen

troi

d(k

ms−

1 )

HCNHCO+

CS13CO

C18O

C17O





11

JCMT beam →

Herschel b

eam →

0 50 100 150 200 250 300 350Eup/k (K)

−6.0

−5.5

−5.0

−4.5

−4.0

V cen

troi

d(k

ms−

1 )

HCNHCO+

CS13CO

C18O

C17O





11

JCMT beam →

Herschel b

eam →• conclusion:

higher Eup / smaller beam→ trace warmer and denser gas

0 50 100 150 200 250 300 350Eup/k (K)

−6.0

−5.5

−5.0

−4.5

−4.0

V cen

troi

d(k

ms−

1 )

HCNHCO+

CS13CO

C18O

C17O


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2

cold tenuous outer envelope

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2


• substructure present at ~104 AU scales (10”)non-trivial distribution of molecular material

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2



• excitation conditions constrained by HIFI lines(also probe dynamics through variable beam size)

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2




• substructure can be resolved by ALMAspecifically:

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2





• high spatial resolution substructure at 102-103 AU scales

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2






• high sensitivity → rare optically thin isotopesthick lines sensitive to detailed distribution

conclusions

12

AFGL2591


10”=104AU

24” (VLA

/OVRO

)

120” (

HARP)

warm methanol spots

warm d

ense

inner

env

elope

N2H +

outflow

outflow

N

E

VLA1

VLA2






• high sensitivity → rare optically thin isotopesthick lines sensitive to detailed distribution

• frequency coverage (100-950 GHz) → broad sample of transitions(at same angular resolution with different array configurations)

conclusions

12

AFGL2591

submillimeter observations of high-mass star formation › sci › meetings › 2010 ›...

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