N'D' Kalinina, A'M' Sobolev, S'V'Salii Ural State University

1
N.D. Kalinina, A.M. Sobolev, S.V.SaliiUral
State University

• "Spectral Survey of NGC 6334 in the range 80.5
  242.0 GHz"

2
Goals

• 1. Reduction of spectral observations of
  molecular cores NGC 6334 I and NGC 6334 I(N)
• 2. Identification of spectral lines
• 3. Compilation of a catalogue of observed
  spectral lines
• 4. Preliminary estimation of physical parameters
  in these objects

3
(No Transcript)
4
Peak position of the radio and FIR sources of
Table 1 plotted over images of the SIMBA
continuum at 250 GHz Diego J. Munoz et al. (2007)
5
Peak position of the radio and FIR sources of
Table 1 plotted over images of the ATCA continuum
at 1.6 GHz
6
Gray scale and black contours 1.3 mm continuum
image of NGC 6334I(-3, 3, 6, 12, 18, 24, 36, 48,
64, 80, 100, 120, 150, 180) x 7.5 mJy/beam

• , x - water masers
• ? - Class II CH3OH
• masers
• - IRS-I 1 and IRS-I 2
• - NH3 peaks
• 6-pointed stars - mid IR sources
• Red cont. - VLA 3.6 cm emission (-5, 5, 15, 30,
  60, 90, 120, 150) mJy beam -1

Hunter et al. (2006)
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1.3 mm continuum image of NGC 6334I(N)(-3, 3, 6,
9, 12, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70,
85, 100, 115) x 6.5 mJa/beam

• - 44 GHz Class I CH3OH masers
• X - 6.7 GHz Class II CH3OH maser
• X - faint 3.6 cm source
• ? - 25 GHz Class I CH3OH masers
• 6-pointed stars - infrared H2 knots
• - NH3 peak

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Star formation complex NGC 6334 I NGC 6334 I(N)

• NGC 6334 I
• Cometary ultra-compact H II region at the centre
• Hot core lt 10 in size
• Central star cluster in NIR
• OH, NH3(3,3), H2O masers and class II CH3OH
  masers
• NGC 6334 I(N)
• Molecular outflow
• H2O and CH3OH masers
• Protostar or Cluster of protostars

9
NGC 6334

• I I(N)

172053.5
172054.8
J2000
-354701
-354501
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Spectral survey in selected frequency ranges

• NGC 6334 I
  NGC 6334 I(N)
• 80.50 81.49 GHz
• 88.45 89.44
  
  
• 94.05 95.04
  
• 96.25 97.24
  
• 109.50 110.50
  
• 147.13 148.14
  
• 156.33 157.33
  
• 164.56 165.57
  
• 219.30 220.30
  
• 238.64 239.64
  
• 240.96 241.97
  

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Observations

• Telescope SEST 15 m
• Receivers
• SESIS 100, SESIS 150, IRAM 115,
• IRAM 230
• AOS
• LRS1 ( 1008.5 MHz )
• LRS2 ( 999.4 MHz )

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Observational parameters

• Cent.freq.(GHz) Sp.Resolution (km s-1) Tsys
  (K) Int.Time (min)
• 
  I I(N)
  I I(N)
• 80.99323 5.14
  374.9 8
• 88.94009 4.72
  188.6 192.5 16 4
• 94.54178 4.40
  235.6 8
• 96.74458 4.30
  212.1 212.1 4 4
• 110.00000 4.30
  214.4 206.9 2 4
• 147.63000 2.84
  178.8 8
• 156.82851 2.68
  543.8 537.9 8 8
• 165.06116 2.54
  262.0 259.4 16 4
• 219.79828 1.90
  235.4 8
• 239.13792 1.76
  295.8 8
• 241.46425 1.74
  295.8 305.0 8 4
  

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AOS non-linearity

• AOS LRS1
• Ranges with central frequencies
• 94.54178 GHz
• 147.63000
• 156.82851  
• 165.06116  
• 239.13792  
• 241.46425

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Identification

• Cologne Database for Molecular Spectroscopy, CDMS
• (Müller et al., J. Mol. Struct. 742, 215, 2005)
• JPL catalog
• (Pickett et al., J. Quant. Spectrosc. Rad.
  Transfer 60, 883, 1998)
• NIST Recommended Rest Frequencies for Observed
  Interstellar
• Molecular Microvawe Transitions
• (Fr. Lovas)

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• DETECTED
• in total 310 spectral details at the level of 3
  sigma
• NGC 6334I
  NGC 6334I(N)
• Identified
• 192
  50
• Unidentified
• U (from Lovas list) 2
• New 44
  22

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Molecules detected

• 2 3 4 5
  6 7 8
  9
• CO OCS HNCO H2CCO CH3OH CH3CCH
  HCOOCH3 CH3OCH3
• CS HCO c-CCCH CH3CN
  CH3CHO C2H5CN
• SO HCN H2CO
  
  C2H5OH
• CN HNC
• SO2

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The most intense lines

• C-13-O
• CO-18
• CS-34
• SO
• HCO
• HCN
• CH3OH

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Spectra of region with central frequency
165061.16 MHz
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Example of Molecular lines catalogue of NGC 6334I

• Line Transition
  FO Area V W
  Ta Ta/sig
  Notes
• 
  (GHz) (Kkms-1)
  (kms-1) (kms-1) (K)
• CH3OCH3 5_2_3_3-5_1_4_3 80,53624
  0,34 -7,83 4,37 0,07 4,24
  Talt5sig b
• CH3OCH3 5_2_3_2-5_1_4_2
  80,53624
  b
• New U 80,80078
  0,28 4,38 0,06 3,49 Talt5sig
• or
• H2CCO 4_3_2-3_3_1
  80,80205 0,28 -5,10 4,37 0,06
  3,49 Talt5sig
• H2CCO 4_3_1-3_3_0 80,80205
• CH3OH, vt0,1 7_2_2-8_1_2 80,99323 1,50
  -7,55 8,29 0,17 10,00
• CH3OH, vt0,1 15_3-14_4 A 88,59496 1,39
  -4,96 6,93 0,19 27,00
• HCN 1_1-0_1 88,63041
• HCN 1_2-0_1
  88,63184 108,00 -6,40 16,07
  6,34 905,71 lr
• HCN 1_0-0_1
  88,63393

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Rotational diagrams in NGC 6334I
log(3k??TBd?/8p3?Sµ2gIgK)
Eu / k
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Rotational temperatures and column densities in
NGC 6334 I

• T (K)
  Nm (cm-2)
• CH3OCH3 122
  2.3 1015
• HCOOCH3 139
  2.4 1015
• CH3CN v80,1 232
  1.9 1013
• CH3CCH 53
  1.1 1014
• CH3OH vt0,1 44
  1.6 1015
• C2H5CN 134
  3.9 1013

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CH3OH rotational temperature diagrams NGC 6334
I NGC 6334 I(N)
log(3k??TBd?/8p3?Sµ2gIgK)
Eu / k
Eu / k
23
CH3OH (96 241 GHz) rotational temperature
diagrams NGC 6334I NGC 6334I(N)
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CH3OHSp reg (GHz) Trot
(K) lg(Column density)

• I I(N)
  I I(N)
• 96 23 11
  15.1 15.4
• 157 44 39
  15.0 14.8
• 165 26 23
  15.1 14.5
• 241 67 18
  15.3 15.3
• 96241 36 16 15.3
  15.4

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Preliminary model parameters from
CH3OH NLTE modeling (series at 96 GHz and 241
GHz)
I I(N)
Temperature (K)
50 20 Specific column
density (cm-3s) 1014.5
1014.8 H2 density (cm-3)
106.5 105.5
CH3OH fractional abundance
10-8 10 -8
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Results of estimation of physical parameters in
NGC 6334(I) and NGC 6334I(N)

• Rotational
  parameters Model parameters
• Temperature (K) I 44 -
  232
• I(N)
• I
  23 - 67 50
  
• I(N)
  11 - 39 20
• Column I 2.11013 -
  2.31015
• densities (cm-2) I(N)
  
• 
  
• I
  1015.0 - 1015.3
  1014.5
• I(N)
  1014.5 - 1015.4
  1014.8
• - using HCOOCH3, CH3OH, CH3CN, CH3OCH3, CH3CCH,
  C2H5CN
• without - using CH3OH

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Conclusions

• 1. Reduction and identification of spectral
  features were carried out.
• 2. The catalogues containing identified and
  unidentified molecular species for both cores
  were compiled.
• 3. Estimation of physical parameters of
  molecular cores was made using
• standard method of rotational diagrams using
  lines of several complex molecules in NGC 6334 I
  
• standard method of rotational diagrams using
  CH3OH lines for both cores
• NLTE modeling of CH3OH emission for both cores.
• 4. Estimation of physical conditions in both
  molecular cores confirm the idea that they
  correspond to different stages of early evolution
  of young stellar objects.

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Acknowledgements

• The authors are very grateful to P.Harjunpaa for
  help in conducting some observations
• and
• I.I.Zinchenko who kindly presented us
  observations in the spectral range with the
  central frequency of 219798.282 GHz.
• All of you for attention!