J/AJ/154/152 CARMA 1 cm spectral line survey of Orion-KL (Friedel+, 2017)
CARMA λ=1 cm spectral line survey of Orion-KL.
Friedel D.N., Looney L.W.
<Astron. J., 154, 152-152 (2017)>
=2017AJ....154..152F 2017AJ....154..152F (SIMBAD/NED BibCode)
ADC_Keywords: Star Forming Region ; Spectra, millimetric/submm ; Radio lines
Keywords: astrochemistry - ISM: individual objects: Orion-KL -
ISM: molecules - radio lines: ISM
Abstract:
Orion-KL is a well-known high-mass star-forming region that has long
been the target of spectral line surveys and searches for complex
molecules. One spectral window where the region had never been
surveyed is around wavelengths of λ=1 cm. This is an important
window to observe, due to the fundamental and low energy transitions
of numerous complex molecules that indicate the maximum spatial extent
of the molecular species; knowing the spatial distribution of a
molecule aids in determining the formation mechanism(s) of that
molecule. Additionally, there are fewer transitions in this window,
reducing confusion caused by blended lines that can be very problematic
at shorter wavelengths (λ<3 mm). In this work, we present the
first spectral line survey at λ=1 cm of the Orion-KL region.
A total of 89 transitions were detected from 14 molecular species and
isotopologues, and two atomic species. The observations were conducted
with the Combined Array for Research in Millimeter-wave Astronomy in
both interferometric and single dish modes.
Description:
The data were taken with the λ=1 cm receivers on the Combined
Array for Research in Millimeter-wave Astronomy (CARMA) 10 and 6 m
telescopes, which operated between 26.938 and 34.938 GHz in single
sideband mode. CARMA was used in its C (24.3-300.0 m baselines) and D
(10.2-119.0 m baselines) configurations to conduct observations in
2014 March-April and 2014 December-2015 April, respectively. The phase
center for all observations was α(J2000)=05h35m14.35s and
δ(J2000)=-05°22'35.0". The synthesized beam sizes are ∼7"x5"
for the C configuration and ∼15"x12" for the D configuration. One
arcsecond is ∼414 au at the distance of Orion-KL (Menten et al.
2007A&A...474..515M 2007A&A...474..515M).
Objects:
------------------------------------------------------
RA (ICRS) DE Designation(s)
------------------------------------------------------
05 35 14.16 -05 22 21.5 Orion-KL = NAME Orion-KL
------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 134 8 Description of Sources in Orion-KL
table3.dat 111 199 Molecular Parameters of Observed Lines
--------------------------------------------------------------------------------
See also:
J/A+A/532/A32 : HCOOCH3 map of Orion-KL (Favre+, 2011)
J/A+A/559/A51 : HC3N in Orion KL (Esplugues+, 2013)
J/ApJ/779/119 : HCOOCH2D detection in Orion KL (Coudert+, 2013)
J/ApJ/784/L7 : CH3CH2SH detection in Orion KL (Kolesnikova+, 2014)
J/ApJS/215/25 : Methyl formate (HCOOCH3) observations (Favre+, 2014)
J/A+A/581/A48 : 1.3cm line survey toward Orion KL (Gong+, 2015)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Name Source name
15 A1 --- n_Name [a] Note on name (1)
17- 18 I2 h RAh ? Hour of Right Ascension (J2000)
20- 21 I2 min RAm ? Minute of Right Ascension (J2000)
23- 28 F6.3 s RAs ? Second of Right Ascension (J2000)
30 A1 --- DE- Sign of the Declination (J2000)
31- 32 I2 deg DEd ? Degree of Declination (J2000)
34- 35 I2 arcmin DEm ? Arcminute of Declination (J2000)
37- 42 F6.3 arcsec DEs ? Arcsecond of Declination (J2000)
44- 47 F4.1 km/s b_VLSR ? Local standard of rest velocity, lower value
49- 52 F4.1 km/s B_VLSR ? Local standard of rest velocity, upper value
54- 56 F3.1 km/s b_FWHM ? Full width at half maximum, lower value
58 I1 km/s B_FWHM ? Full width at half maximum, upper value
60-128 A69 --- Desc Description
130-134 A5 --- Ref Reference(s) (2)
--------------------------------------------------------------------------------
Note (1): Note as follows:
a = The Orion Bar is a very extended structure; no single coordinate set can
describe its position. The structure is very large and has a wide variety
of velocities, FWHM, and structure sizes.
Note (2): Reference as follows:
1 = Plambeck et al. (2013ApJ...765...40P 2013ApJ...765...40P);
2 = Mundy et al. (1986ApJ...304L..51M 1986ApJ...304L..51M);
3 = Eisner & Carpenter (2006ApJ...641.1162E 2006ApJ...641.1162E);
4 = Widicus Weaver & Friedel (2012ApJS..201...16W 2012ApJS..201...16W);
5 = Wright et al. (1996ApJ...469..216W 1996ApJ...469..216W);
6 = Friedel & Snyder (2008ApJ...672..962F 2008ApJ...672..962F);
7 = Friedel & Widicus Weaver (2012ApJS..201...17F 2012ApJS..201...17F);
8 = This work;
9 = Goicoechea et al. (2016Natur.537..207G 2016Natur.537..207G);
10 = O'Dell et al. (2017ApJ...837..151O 2017ApJ...837..151O).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Line [1/15] Observed line (1)
4- 28 A25 --- Quant Quantum numbers
30 A1 --- n_Quant [b] Note on Quant (2)
32- 39 F8.2 MHz RFreq [27215.57/34857.2] Rest frequency
41- 44 F4.2 MHz e_RFreq [0/0.2] Uncertainty in RFreq
46- 51 F6.1 K Eu [1.4/1691.1]? Upper state energy
53- 56 F4.1 D+2 Smu2 [0.2/99.4]? Line strength times the
appropriate dipole moment Sµ2
(in Debye2)
58- 61 F4.1 arcsec Bmaj [5.7/17.2] Synthesized beam major axis
θa
63- 66 F4.1 arcsec Bmin [4.2/12.2] Synthesized beam minor axis
θb
67 A1 --- n_Bmin [cd] Note on Bmin (3)
69- 74 F6.3 Jy I0 [-0.11/1.77]? Fitted intensity (in Jy/beam)
76- 77 I2 Jy e_I0 [0/15]? Uncertainty in I0
78 A1 --- n_I0 [efhi] Note on I0 (4)
80- 83 F4.1 km/s VLSR [-8.1/28]? Fitted local standard of rest
velocity
85- 86 I2 km/s e_VLSR [0/87]? Uncertainty in VLSR
87 A1 --- n_VLSR [g] Note on VLSR (5)
89- 92 F4.1 km/s FWHM [0.5/41.5]? Fitted full width at half maximum
94- 96 I3 km/s e_FWHM [0/119]? Uncertainty in FWHM
98-102 A5 --- Pos Position where the spectrum was taken (6)
104-107 F4.1 mJy/beam rms [6/45.4]? rms noise
109-111 A3 --- Config Array configuration the data were taken in (7)
--------------------------------------------------------------------------------
Note (1): Observed line as follows:
1 = CH3OH;
2 = 13CH3OH;
3 = Hydrogen recombination line;
4 = Helium recombination line;
5 = H2CO;
6 = H2CS;
7 = SO;
8 = 34SO;
9 = SO2;
10 = 34SO2;
11 = NH3;
12 = CH3OCHO;
13 = CH3OCH3;
14 = CH3CH2CN;
15 = HC3N.
Note (2): Note as follows:
b = This transition was part of the mosaic and single dish observations.
Note (3): Note as follows:
c = These transitions of 13CH3OH and CH3CH2CN are blended;
d = Spectral profile is too complex for a reliable fit.
Note (4): Note as follows:
e = Uncertainty could not be calculated;
f = There could be more components, and likely are, but due to high noise, no
reliable fits could be made;
h = In order to obtain line fits, the ratio of the lines was fixed - as was
the FWHM;
i = Intensity ratios were fixed for low opacity.
Note (5): Note as follows:
g = Intensities are free, while VLSR and FWHM were forced to be the same
for each pair.
Note (6): See Figure 13 and 17 for specific meanings of the position at which
the spectra of the detected H recombination lines and He recombination lines
were taken, respectively.
See Table 1 for other positions.
If it is blank, then spectra are taken from the emission peak.
Note (7): The synthesized beam sizes are ∼7"x5" for the C configuration and
∼15"x12" for the D configuration.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 15-Jun-2018