J/ApJ/897/176 19 species in 14 super stars clusters in NGC 253 (Krieger+, 2020)
The Molecular Interstellar Medium in the Super Star Clusters of the Starburst
NGC 253.
Krieger N., Bolatto A.D., Leroy A.K., Levy R.C., Mills E.A.C., Meier D.S.,
Ott J., Veilleux S., Walter F., Weiss A.
<Astrophys. J., 897, 176 (2020)>
=2020ApJ...897..176K 2020ApJ...897..176K
ADC_Keywords: Clusters, open; Spectra, millimetric/submm; Interstellar medium;
Molecular data
Keywords: Starburst galaxies ; Astrochemistry ; Star clusters ;
Dense interstellar clouds ; Interstellar medium ; Star formation
Abstract:
We present submillimeter spectra of the (proto-)super star cluster
(SSC) candidates in the starbursting center of the nearby galaxy NGC
253 identified by Leroy et al. The 2.5pc resolution of our Atacama
Large Millimeter/submillimeter Array cycle 3 observations approaches
the size of the SSCs and allows for the study of physical and chemical
properties of the molecular gas in these sources. In the 14 SSC
sources and in the frequency ranges 342.0-345.8GHz and 353.9-357.7GHz,
we detect 55 lines belonging to 19 different chemical species. The
SSCs differ significantly in chemical complexity, with the richest
clusters showing 19 species and the least complex showing four
species. We detect HCN isotopologues and isomers (H13CN, HC15N,
H15NC), abundant HC3N, SO and S18O, SO2, and H2CS. The gas ratios
CO/HCN, CO/HCO+ are low, ∼1-10, implying high dense gas fractions in
the SSCs. Line ratio analyses suggests chemistry consistent with
photon-dominated regions and mechanical heating. None of the SSCs near
the galaxy center show line ratios that imply an X-ray-dominated
region, suggesting that heating by any (still unknown) active galactic
nucleus does not play a major role. The gas temperatures are high in
most sources, with an average rotational temperature of ∼130K in SO2.
The widespread existence of vibrationally excited HCN and HC3N
transitions implies strong infrared radiation fields, potentially
trapped by a greenhouse effect due to high continuum opacities.
Description:
We present high-resolution Atacama Large Millimeter/submillimeter
Array (ALMA) observations of the super star clusters (SSCs) in the
starbursting center of NGC253. Our spectral setup in band 7 covers a
wealth of molecular species and pushes at resolving the compact
(proto-)super star clusters with 2.5pc spatial resolution. In spectra
focused on the SSCs, we detect up to 55 lines of 19 species. Modeling
the spectra with xclass allows us to independently study
observation-based line ratios and modeled physical quantities.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 244 66 The fitted integrated intensities
table2.dat 159 284 The parameters fitted with XCLASS
table3.dat 107 14 Dense gas fractions
fig1.dat 20 40222 Overview and relative comparison of the spectra and
xclass fits of the 14 SSCs
--------------------------------------------------------------------------------
See also:
J/A+A/579/A101 : 3mm molecular line survey of 8 AGN (Aladro+, 2015)
J/ApJ/858/90 : Radial profiles of 5 nearby galaxies (Gallagher+, 2018)
J/A+A/629/A6 : 3 starburst galaxies 12C/13C ALMA datacubes (Tang+, 2019)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Species Molecule identifier
7- 8 I2 --- Rotmin [3/47] Rotational state, minimum
10- 13 F4.2 --- e_Rotmin [0.2/9]? Error on Rotmin
15- 16 I2 --- Rotmax [2/46] Rotationale state, maximum
18- 21 F4.2 --- e_Rotmax [0/8]? Error on Rotmax
23- 33 A11 --- Vib Vibrational state
35 I1 --- Comp [0/5] Spectral component
37- 40 I4 K.km/s 16th(SSC1) [4/1585]? SSC1 16th percentile lower bound,
lower 1sigma error, on integrated intensity
42- 45 I4 K.km/s 50th(SSC1) [6/1741]? SSC1 50th percentile median of
integrated intensity
47- 50 I4 K.km/s 84th(SSC1) [8/2199]? SSC1 84th percentile upper bound,
upper 1sigma error on integrated intensity
52- 55 I4 K.km/s 16th(SSC2) [1/1677]? SSC2 16th percentile lower bound,
lower 1sigma error on integrated intensity
57- 60 I4 K.km/s 50th(SSC2) [1/2328]? SSC2 50th percentile median of
integrated intensity
62- 65 I4 K.km/s 84th(SSC2) [1/2841]? SSC2 84th percentile upper bound,
upper 1sigma error on integrated intensity
67- 70 I4 K.km/s 16th(SSC3) [2/2131]? SSC3 16th percentile lower bound,
lower 1sigma error on integrated intensity
72- 75 I4 K.km/s 50th(SSC3) [1/2187]? SSC3 50th percentile median of
integrated intensity
77- 80 I4 K.km/s 84th(SSC3) [2/2241]? SSC3 84th percentile upper bound,
upper 1sigma error on integrated intensity
82- 85 I4 K.km/s 16th(SSC4) [3/2138]? SSC4 16th percentile lower bound,
lower 1sigma error on integrated intensity
87- 90 I4 K.km/s 50th(SSC4) [1/2654]? SSC4 50th percentile median of
integrated intensity
92- 95 I4 K.km/s 84th(SSC4) [1/2727]? SSC4 84th percentile upper bound,
upper 1sigma error on integrated intensity
97-100 I4 K.km/s 16th(SSC5) [2/2447]? SSC5 16th percentile lower bound,
lower 1sigma error on integrated intensity
102-105 I4 K.km/s 50th(SSC5) [2/2460]? SSC5 50th percentile median of
integrated intensity
107-110 I4 K.km/s 84th(SSC5) [1/2474]? SSC5 84th percentile upper bound,
upper 1sigma error on integrated intensity
112-115 I4 K.km/s 16th(SSC6) [28/3233]? SSC6 16th percentile lower bound,
lower 1sigma error on integrated intensity
117-120 I4 K.km/s 50th(SSC6) [34/3509]? SSC6 50th percentile median of
integrated intensity
122-125 I4 K.km/s 84th(SSC6) [39/3620]? SSC6 84th percentile upper bound,
upper 1sigma error on integrated intensity
127-130 I4 K.km/s 16th(SSC7) [33/3157]? SSC7 16th percentile lower bound,
lower 1sigma error on integrated intensity
132-135 I4 K.km/s 50th(SSC7) [40/3327]? SSC7 50th percentile median of
integrated intensity
137-140 I4 K.km/s 84th(SSC7) [45/3380]? SSC7 84th percentile upper bound,
upper 1sigma error on integrated intensity
142-145 I4 K.km/s 16th(SSC8) [1/3567]? SSC8 16th percentile lower bound,
lower 1sigma error on integrated intensity
147-150 I4 K.km/s 50th(SSC8) [1/3578]? SSC8 50th percentile median of
integrated intensity
152-155 I4 K.km/s 84th(SSC8) [1/3588]? SSC8 84th percentile upper bound,
upper 1sigma error on integrated intensity
157-160 I4 K.km/s 16th(SSC9) [46/2795]? SSC9 16th percentile lower bound,
lower 1sigma error on integrated intensity
162-165 I4 K.km/s 50th(SSC9) [51/2919]? SSC9 50th percentile median of
integrated intensity
167-170 I4 K.km/s 84th(SSC9) [60/3090]? SSC9 84th percentile upper bound,
upper 1sigma error on integrated intensity
172-175 I4 K.km/s 16th(SSC10) [9/1495]? SSC10 16th percentile lower bound,
lower 1sigma error on integrated intensity
177-180 I4 K.km/s 50th(SSC10) [11/3004]? SSC10 50th percentile median of
integrated intensity
182-185 I4 K.km/s 84th(SSC10) [13/3362]? SSC10 84th percentile upper bound
upper 1sigma error on integrated intensity
187-190 I4 K.km/s 16th(SSC11) [1/2419]? SSC11 16th percentile lower bound,
lower 1sigma error on integrated intensity
192-195 I4 K.km/s 50th(SSC11) [2/2978]? SSC11 50th percentile median of
integrated intensity
197-200 I4 K.km/s 84th(SSC11) [2/3889]? SSC11 84th percentile upper bound,
upper 1sigma error on integrated intensity
202-205 I4 K.km/s 16th(SSC12) [9/2573]? SSC12 16th percentile lower bound,
lower 1sigma error on integrated intensity
207-210 I4 K.km/s 50th(SSC12) [26/4132]? SSC12 50th percentile median of
integrated intensity
212-215 I4 K.km/s 84th(SSC12) [29/4901]? SSC12 84th percentile upper bound
upper 1sigma error on integrated intensity
217-219 I3 K.km/s 16th(SSC13) [2/807]? SSC13 16th percentile lower bound,
lower 1sigma error on integrated intensity
221-224 I4 K.km/s 50th(SSC13) [2/3552]? SSC13 50th percentile median of
integrated intensity
226-229 I4 K.km/s 84th(SSC13) [2/4182]? SSC13 84th percentile upper bound,
upper 1sigma error on integrated intensity
231-234 I4 K.km/s 16th(SSC14) [4/5447]? SSC14 16th percentile lower bound,
lower 1sigma error on integrated intensity
236-239 I4 K.km/s 50th(SSC14) [5/5486]? SSC14 50th percentile median of
integrated intensity
241-244 I4 K.km/s 84th(SSC14) [5/5504]? SSC14 84th percentile upper bound,
upper 1sigma error on integrated intensity
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- SSC [1/14] SSC identifier
7- 18 A12 --- Species Molecule
22- 33 A12 --- Vib Vibrational state
37- 45 I9 --- Comp [0/5] spectral component
49- 53 F5.2 [cm-2] logN-16th [10/19] log10 column density 16th percentile
lower bound; lower 1sigma error
57- 61 F5.2 [cm-2] logN-50th [10.1/19] log10 column density 50th percentile
median
65- 69 F5.2 [cm-2] logN-84th [10.6/19] log10 column density 84th percentile
upper bound; upper 1sigma error
73- 76 F4.1 km/s lw-16th [7.3/88.4] Linewidth 16th percentile lower
bound; lower 1sigma error
80- 83 F4.1 km/s lw-50th [9.4/96] Linewidth 50th percentile median
87- 90 F4.1 km/s lw-84th [10.3/99.6] Linewidth 84th percentile upper
bound; upper 1sigma error
94- 99 F6.1 km/s v-16th [-142.2/153.3] Velocity 16th percentile lower
bound; lower 1sigma error
103-108 F6.1 km/s v-50th [-131.7/155] Velocity 50th percentile median
112-117 F6.1 km/s v-84th [-120/162.8] Velocity 84th percentile upper
bound; upper 1sigma error
121-123 I3 K T-16th [36/481] Kinetic temperature 16th percentile
lower bound; lower 1sigma error
127-129 I3 K T-50th [47/500] Kinetic temperature 50th percentile
median
133-135 I3 K T-84th [104/807] Kinetic temperature 84th percentile
upper bound; upper 1sigma error
139-143 F5.2 --- tau-16th [0/38.67] Integrated opacity 16th percentile
lower bound; lower 1sigma error
147-151 F5.2 --- tau-50th [0/38.85] Integrated opacity 50th percentile
median
155-159 F5.2 --- tau-84th [0/39.02] Integrated opacity 84th percentile
upper bound; upper 1sigma error
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- SSC [1/14] SSC identifier
4- 7 F4.1 --- Ri-CO/HCN [0.9/12.7] Line intensity ratio CO/HCN
9- 11 F3.1 --- e_Ri-CO/HCN [0/5.1] Negative error on Ri-CO/HCN
13- 15 F3.1 --- E_Ri-CO/HCN [0/7.6] Positive error on Ri-CO/HCN
17- 20 F4.1 --- Ri-CO/CS [1.4/29.1] Line intensity ratio CO/CS
22- 24 F3.1 --- e_Ri-CO/CS [0/5.4] Negative error on Ri-CO/CS
26- 28 F3.1 --- E_Ri-CO/CS [0/9.3] Positive error on Ri-CO/CS
30- 32 F3.1 --- Ri-HCN/HCO [0.5/1.6] Line intensity ratio HCN/HCO+
34- 36 F3.1 --- e_Ri-HCN/HCO [0/0.5] Negative error on Ri-HCN/HCO
38- 40 F3.1 --- E_Ri-HCN/HCO [0/0.6] Positive error on Ri-HCN/HCO
42- 44 F3.1 --- Ri-CS/HCN [0.1/0.9] Line intensity ratio CS/HCN
46- 48 F3.1 --- e_Ri-CS/HCN [0/0.3] Negative error on Ri-CS/HCN
50- 52 F3.1 --- E_Ri-CS/HCN [0/1.4] Positive error on Ri-CS/HCN
54- 58 I5 --- Rn-CO/HCN [760/11000] Column density ratio CO/HCN
60- 63 I4 --- e_Rn-CO/HCN [17/3100] Negative error on Rn-CO/HCN
65- 68 I4 --- E_Rn-CO/HCN [9/7500] Positive error on Rn-CO/HCN
70- 73 I4 --- Rn-CO/CS [400/8700] Column density ratio CO/HCN
75- 78 I4 --- e_Rn-CO/CS [7/1800] Negative error on Rn-CO/CS
80- 83 I4 --- E_Rn-CO/CS [4/2700] Positive error on Rn-CO/CS
85- 87 F3.1 --- Rn-HCN/HCO [0.8/2.8] Column density ratio HCN/HCO+
89- 91 F3.1 --- e_Rn-HCN/HCO [0/0.8] Negative error on Rn-HCN/HCO
93- 95 F3.1 --- E_Rn-HCN/HCO [0/1.1] Positive error on Rn-HCN/HCO
97- 99 F3.1 --- Rn-CS/HCN [0.3/2.5] Column density ratio CS/HCN
101-103 F3.1 --- e_Rn-CS/HCN [0/0.9] Negative error on Rn-CS/HCN
105-107 F3.1 --- E_Rn-CS/HCN [0/3.7] Positive error on Rn-CS/HCN
--------------------------------------------------------------------------------
Byte-by-byte Description of file: fig1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- SSC [1/14] SSC identifier
4- 12 F9.5 GHz Freq [342/359] Rest frequency
14- 20 F7.3 K Tb [-4.29/113] Brightness temperature
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 11-Oct-2021