J/ApJS/263/13 34.8-50GHz obs. toward Orion KL (Liu+, 2022)
A Q-band line survey toward Orion KL using the Tianma Radio Telescope.
Liu X., Liu T., Shen Z., Qin S.-L., Luo Q., Cheng Yu, Gu Q., Zhang T.,
Zhu F.-Y., Liu S.-Y., Lu X., Zhao R., Zhong W., Wu Y., Li J., Zhao Z.,
Wang J., Liu Q., Xia Bo, Li B., Fu Li, Yan Z., Zhang C., Wang L., Ye Q.,
Tatematsu K., Liu H., Shang H., Xu F., Lee C.-F., Zhang C., Dutta S.
<Astrophys. J. Suppl. Ser., 263, 13 (2022)>
=2022ApJS..263...13L 2022ApJS..263...13L
ADC_Keywords: Star Forming Region; Molecular clouds; Radio lines
Keywords: Molecular clouds ; Molecular spectroscopy ; H II regions ;
Star forming regions
Abstract:
We have conducted a line survey toward Orion KL using the Q-band
receiver of the Tianma 65m radio telescope (TMRT), covering 34.8-50GHz
with a velocity resolution between 0.79 and 0.55km/s, respectively.
The observations reach a sensitivity of the level of 1-8mK, proving
that the TMRT is sensitive for conducting deep-line surveys. In total,
597 Gaussian features are extracted. Among them, 177 radio
recombination lines (RRLs) are identified, including 126, 40, and
11 RRLs of hydrogen, helium, and carbon, with a maximum Δn of
16, 7, and 3, respectively. The carbon RRLs are confirmed to originate
from photodissociation regions with a VLSR∼9km/s. In addition,
371 molecular transitions of 53 molecular species are identified.
Twenty-one molecular species of this survey were not firmly detected
in the Q band by Rizzo+ (2017, J/A+A/605/A76), including species such
as H2CS, HCOOH, C2H5OH, H213CO, H2CCO, CH3CHO,
CH2OCH2, HCN υ2=1, and CH3OCHO υt=1. In
particular, the vibrationally excited states of ethyl cyanide
(C2H5CN υ13/υ21) are for the first time firmly
detected in the Q band. NH3 (15,15) and (16,16) are identified, and
they are so far the highest transitions of the NH3 inversion lines
detected toward Orion KL. All of the identified lines can be
reproduced by a radiative transfer model.
Description:
The observations were carried out using the Tianma 65m radio telescope
(TMRT) of the Shanghai Astronomical Observatory. Receivers from the
L to Q band are available, covering a frequency range of 1-50GHz.
Our observations toward Orion KL were conducted during 2022 March 9-29.
The targeted position is RAJ2000=05:35:14.55, DEJ2000=-05:22:31.0
Objects:
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RA (ICRS) DE Designation(s)
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05 35 14.16 -05 22 21.4 Orion KL = NAME Orion KL
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig2.dat 21 166024 The Orion KL spectrum in the Q band observed
by the Tianma 65m radio telescope (TMRT)
table3.dat 123 637 Line list with molecular lines and blended
radio recombination lines (RRLs)
table4.dat 67 166 Line list with unblended RRLs
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See also:
VI/64 : Recombination line intensities for hydrogenic ions (Storey+ 1995)
J/A+A/327/1177 : Kinematics and electron temperatures in Orion A (Wilson+ 1997)
J/ApJS/156/127 : 350µm molecular line survey of Orion KL (Comito+, 2005)
J/ApJS/175/277 : Submillimeter-Continuum SCUBA detections (Di Francesco+, 2008)
J/A+A/559/A47 : Sgr B2(N) and Sgr B2(M) IRAM 30m line survey (Belloche+, 2013)
J/ApJ/768/81 : Ethyl cyanide, CH3CH2CN, vibrational states (Daly+, 2013)
J/A+A/559/A51 : HC3N in Orion KL (Esplugues+, 2013)
J/A+A/581/A71 : Orion-KL substructure at 1.3mm (Feng+, 2015)
J/A+A/581/A48 : 1.3cm line survey toward Orion KL (Gong+, 2015)
J/A+A/601/A4 : IRC+10216 carbon chains mapped with ALMA (Agundez+, 2017)
J/A+A/605/A76 : Spectrum of Orion KL between 41.5 and 50GHz (Rizzo+, 2017)
J/A+A/606/A74 : IRC +10216 13.3GHz-18.5GHz spectrum (Zhang+, 2017)
J/ApJ/849/139 : Interstellar acetone (CH3COCH3) in 3 regions (Zou+, 2017)
J/A+A/627/A162 : L1489 starless core carbon-chain-producing region (Wu+, 2019)
J/ApJ/900/L10 : X-band of the GOTHAM Large Project for TMC-1 (McGuire+, 2020)
J/A+A/647/A42 : Detected CH2 spectra (Jacob+, 2021)
J/A+A/658/A39 : 31.0-50.3 GHz observations of IRC+10216 (Pardo+, 2022)
Byte-by-byte Description of file: fig2.dat
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Bytes Format Units Label Explanations
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1- 10 F10.4 MHz Freq [34800.69/50001.01] Rest frequency (1)
12- 21 E10.3 K Tmb [-1.23/225.6] Brightness temperature
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Note (1): With a Doppler correction applied adopting a VLSR of 6km/s.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 8 F8.2 MHz Fobs [34824.24/49962.73] Observed frequency (G1)
10 A1 --- f_Fobs [b] Flag on Fobs (G2)
12- 31 A20 --- Species Species name
33- 41 F9.3 MHz Frest [34824/49962.84]? Rest frequency
43- 67 A25 --- Trans Transition identifier (1)
69- 74 F6.1 K Eu [1.9/3523.2]? Upper level energy
76- 81 F6.3 10-6/s Aij [0.003/11.7]? Einstein coefficient
83- 90 F8.4 K.km/s intTMBdV [0.01/640]? Integrated line intensity
92- 97 F6.3 K.km/s e_intTMBdV [0.002/19]? Uncertainty in intTMBdV
99-107 F9.3 km/s DeltaV [1/42]? Line width
109-114 F6.3 km/s e_DeltaV [0.008/10]? Uncertainty in DeltaV
116-123 E8.2 K TMBpeak [0.0027/172]? Line peak intensity
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Note (1): Rows with a same species name, Frest and transition label correspond
to different emission components of a same transition.
The transition labels for HCN vt=1 are Jp with p the parity.
The transition labels for CH3OCH3 are JKs with s the symmetry substate.
The transition labels are (J, K) for NH3 convention lines.
The transition labels for CH3CN vt=1 are JKp with p the parity.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 F8.2 MHz Fobs [34941.26/49728.35] Observed frequency (G1)
10 A1 --- f_Fobs [b] Flag on Fobs (G2)
12- 24 A13 --- Species Species name
26- 34 F9.3 MHz Frest [34940/49726.7] Rest frequency
36- 41 F6.3 K.km/s intTMBdV [0.04/45.8]? Integrated line intensity
43- 47 F5.3 K.km/s e_intTMBdV [0.002/0.3]? Uncertainty in intTMBdV
49- 53 F5.2 km/s DeltaV [2.2/34]? Line width
55- 58 F4.2 km/s e_DeltaV [0.02/8]? Uncertainty in DeltaV
60- 67 E8.2 K TMBpeak [0.004/1.7]? Line peak intensity
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Global notes:
Note (G1): Doppler correction has been applied to Fobs assuming a source
velocity of 6km/s in LSR (Sect. 2.3). Duplicated Fobs values
correspond to blended lines.
Note (G2): Flag as follows:
b = The corresponding transition has been firmly detected and
resolved by Rizzo+ 2017, J/A+A/605/76
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 22-Nov-2022