J/ApJS/162/346 Abundance gradients in the Galaxy (Rudolph+, 2006)
Abundance gradients in the Galaxy.
Rudolph A.L., Fich M., Bell G.R., Norsen T., Simpson J.P., Haas M.R.,
Erickson E.F.
<Astrophys. J. Suppl. Ser., 162, 346-374 (2006)>
=2006ApJS..162..346R 2006ApJS..162..346R
ADC_Keywords: Abundances ; H II regions ; Spectra, infrared
Keywords: Galaxy: abundances - H II regions - ISM: abundances
Abstract:
Six HII regions at galactocentric distances of R=10-15kpc have been
observed in the far-IR emission lines of [OIII] (52µm, 88µm),
[NIII] (57µm), and [SIII] (19µm) using the Kuiper Airborne
Observatory. These observations have been combined with Very Large
Array radio continuum observations of these sources to determine the
abundances of O++, N++, and S++ relative to hydrogen. In addition,
eight of the most recent sets of measurements of ionic line strengths
in HII regions have been reanalyzed in order to attempt to reconcile
differences in optical versus far-IR abundance determinations. We have
in total 168 sets of observations of 117 HII regions in our analysis.
Description:
The FIR observations of [SIII] (19µm), [OIII] (52, 88µm), and
[NIII] (57µm) were made with the 91cm telescope of the KAO using
the facility Cryogenic Grating Spectrometer (CGS) on flights of 1995
August 6, 10, and 12.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 100 122 HII region distances
refs.dat 73 44 References
table6.dat 314 168 Final abundances
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See also:
VII/50 : CO Radial Velocities Toward Galactic HII Regions (Blitz+ 1982)
VIII/58 : Survey of Radio HII Regions in the Northern Sky
(Lockman+ 1989)
J/A+A/275/67 : Velocity Field of the outer Galaxy (Brand+ 1993)
J/A+A/171/261 : Radio Recombination Lines of Southern HII Regions
(Caswell+ 1987)
J/AJ/106/1906 : NGC 6611: A Cluster Caught in the Act (Hillenbrand+ 1993)
J/AJ/113/1733 : Orion Nebula Cluster population (Hillenbrand 1997)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name H II region name (1)
14- 18 F5.2 kpc R Galactocentric distance (2)
20- 23 F4.2 kpc e_R ? Best estimate uncertainty in R
25- 29 F5.2 kpc Dist Distance from the Sun (2)
31- 34 F4.2 kpc e_Dist ? Best estimate uncertainty in Dist
36- 37 A2 --- Meth Method used to derive R and Dist (3)
39- 48 A10 --- r_R Reference(s) from which R and Dist were taken
50- 69 A20 --- OName Other Name
71-100 A30 --- Obs Observed by (detailed in refs.dat)
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Note (1): As used by the first of the six groups to observe the source.
Note (2): We assumed a flat rotation curve, and used the IAU accepted values
of distance to the Galactic Center (R0=8.5kpc) and circular
velocity of the local standard of rest (Θ0=220km/s).
Note (3): Method used to derive R and Dist, defined as follows:
SP = spectrophotometric;
K = kinematic;
GC = galactic center;
M = maser proper motions.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- Ref Reference code
7- 25 A19 --- Bibcode Bibcode
27- 52 A26 --- Aut Author's name
54- 73 A20 --- Com Comment
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name H II region name (1)
17- 20 A4 --- Ref Primary source reference
21 A1 --- n_Te Method used to compute Te (2)
23- 27 F5.2 kpc R Galactocentric distance (3)
29- 33 I5 cm-3 ne Electron density
35- 38 I4 cm-3 e_ne Error in ne
40- 43 F4.1 10+3K Te Electron temperature
45- 47 F3.1 10+3K e_Te Error in Te
49- 52 F4.2 [Sun] N+/H+ ? Log of the N+/H+ number abundance
54- 57 F4.2 [Sun] E_N+/H+ ? Upper limit error in N+/H+
59- 62 F4.2 [Sun] e_N+/H+ ? Lower limit error in N+/H+
64- 67 F4.2 [Sun] N++/H+ ? Log of the N++/H+ number abundance
69- 72 F4.2 [Sun] E_N++/H+ ? Upper limit error in N++/H+
74- 77 F4.2 [Sun] e_N++/H+ ? Lower limit error in N++/H+
79- 82 F4.2 [Sun] O+/H+ ? Log of the O+/H+ number abundance
84- 87 F4.2 [Sun] E_O+/H+ ? Upper limit error in O+/H+
89- 92 F4.2 [Sun] e_O+/H+ ? Lower limit error in O+/H+
94- 97 F4.2 [Sun] O++/H+ ? Log of the O++/H+ number abundance
99-102 F4.2 [Sun] E_O++/H+ ? Upper limit error in O++/H+
104-107 F4.2 [Sun] e_O++/H+ ? Lower limit error in O++/H+
109-112 F4.2 [Sun] S+/H+ ? Log of the S+/H+ number abundance
114-117 F4.2 [Sun] E_S+/H+ ? Upper limit error in S+/H+
119-122 F4.2 [Sun] e_S+/H+ ? Lower limit error in S+/H+
124-127 F4.2 [Sun] S++/H+ ? Log of the S++/H+ number abundance
129-132 F4.2 [Sun] E_S++/H+ ? Upper limit error in S++/H+
134-137 F4.2 [Sun] e_S++/H+ ? Lower limit error in S++/H+
139-142 F4.2 [Sun] S+++/H+ ? Log of the S+++/H+ number abundance
144-147 F4.2 [Sun] E_S+++/H+ ? Upper limit error in S+++/H+
149-152 F4.2 [Sun] e_S+++/H+ ? Lower limit error in S+++/H+
154-158 F5.2 [Sun] N+/O+ ? Log of the N+/O+ number abundance
160-163 F4.2 [Sun] E_N+/O+ ? Upper limit error in N+/O+
165-168 F4.2 [Sun] e_N+/O+ ? Lower limit error in N+/O+
170-174 F5.2 [Sun] N++/O+ ? Log of the N++/O+ number abundance
176-179 F4.2 [Sun] E_N++/O+ ? Upper limit error in N++/O+
181-184 F4.2 [Sun] e_N++/O+ ? Lower limit error in N++/O+
186-189 F4.1 10+3K Teff Effective temperature
191-193 F3.1 10+3K e_Teff Error in Teff
195-198 F4.2 --- ICF-N+ ? N+ ionization correction factor
200-203 F4.2 --- e_ICF-N+ ? Error in ICF-N+
205-208 F4.2 --- ICF-N++ ? N++ ionization correction factor
210-213 F4.2 --- e_ICF-N++ ? Error in ICF-N++
215-218 F4.2 [Sun] N/H ? Log of the N/H number abundance
220-223 F4.2 [Sun] E_N/H ? Upper limit error on N/H
225-228 F4.2 [Sun] e_N/H ? Lower limit error on N/H
230-233 F4.2 --- ICF-O+ ? O+ ionization correction factor
235-238 F4.2 --- e_ICF-O+ ? Error in ICF-O+
240-243 F4.2 --- ICF-O++ ? O++ ionization correction factor
245-248 F4.2 --- e_ICF-O++ ? Error in ICF-O++
250-253 F4.2 [Sun] O/H ? Log of the O/H number abundance
255-258 F4.2 [Sun] E_O/H ? Upper limit error on O/H
260-263 F4.2 [Sun] e_O/H ? Lower limit error on O/H
265-268 F4.2 --- ICF-S+ ? S+ ionization correction factor
270-273 F4.2 --- e_ICF-S+ ? Error in ICF-S+
275-278 F4.2 --- ICF-S++ ? S++ ionization correction factor
280-283 F4.2 --- e_ICF-S++ ? Error in ICF-S++
285-288 F4.2 [Sun] S/H ? Log of the S/H number abundance
290-293 F4.2 [Sun] E_S/H ? Upper limit error on S/H
295-298 F4.2 [Sun] e_S/H ? Lower limit error on S/H
300-304 F5.2 [Sun] N/O ? Log of the N/O number abundance
306-309 F4.2 [Sun] E_N/O ? Upper limit error on N/O
311-314 F4.2 [Sun] e_N/O ? Lower limit error on N/O
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Note (1): As used by the first of the six groups to observe the source.
Note (2): Note on Te (for data from 1996MNRAS.280..720V 1996MNRAS.280..720V), defined as follows:
d = Electron temperature directly (spectroscopically) determined;
i = Adopted electron temperature derived from photoionization model fitting.
Note (3): We assumed a flat rotation curve, and used the IAU accepted values
of distance to the Galactic Center (R0=8.5kpc) and circular
velocity of the local standard of rest (Θ0=220km/s).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 03-Jan-2007