J/ApJ/830/4 HII region abundances in NGC 5457 (M101) (Croxall+, 2016)
CHAOS III: gas-phase abundances in NGC 5457.
Croxall K.V., Pogge R.W., Berg D.A., Skillman E.D., Moustakas J.
<Astrophys. J., 830, 4-4 (2016)>
=2016ApJ...830....4C 2016ApJ...830....4C (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; H II regions ; Spectroscopy
Keywords: galaxies: individual: NGC 5457; galaxies: ISM; ISM: lines and bands
Abstract:
We present Large Binocular Telescope observations of 109 HII regions
in NGC 5457 (M101) obtained with the Multi-Object Double Spectrograph.
We have robust measurements of one or more temperature-sensitive
auroral emission lines for 74 HII regions, permitting the measurement
of "direct" gas-phase abundances. Comparing the temperatures derived
from the different ionic species, we find: (1) strong correlations of
T[NII] with T[SIII] and T[OIII], consistent with little or no
intrinsic scatter; (2) a correlation of T[SIII] with T[OIII], but with
significant intrinsic dispersion; (3) overall agreement between
T[NII], T[SII], and T[OII], as expected, but with significant
outliers; (4) the correlations of T[NII] with T[SIII] and T[OIII]
match the predictions of photoionization modeling while the
correlation of T[SIII] with T[OIII] is offset from the prediction of
photoionization modeling. Based on these observations, which include
significantly more observations of lower excitation HII regions,
missing in many analyses, we inspect the commonly used ionization
correction factors (ICFs) for unobserved ionic species and propose new
empirical ICFs for S and Ar. We have discovered an unexpected
population of HII regions with a significant offset to low values in
Ne/O, which defies explanation. We derive radial gradients in O/H and
N/O which agree with previous studies. Our large observational
database allows us to examine the dispersion in abundances, and we
find intrinsic dispersions of 0.074±0.009 in O/H and 0.095±0.009
in N/O (at a given radius). We stress that this measurement of the
intrinsic dispersion comes exclusively from direct abundance
measurements of HII regions in NGC 5457.
Description:
Optical spectra of NGC 5457 were taken using Multi-Object Double
Spectrographs (MODS) on the Large Binocular Telescope (LBT) during the
spring semester of 2015. We obtained simultaneous blue and red spectra
using the G400L (R∼1850) and G670L (R∼2300) gratings, respectively.
This setup provided broad spectral coverage extending from 3200 to
10000Å.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 84 102 NGC 5457 MODS/LBT observations
table3.dat 60 6630 Line fluxes relative to Hβ
table4.dat 359 77 Abundances in NGC 5457
--------------------------------------------------------------------------------
See also:
J/ApJ/808/42 : CHemical Abundances of Spirals (CHAOS) II. M51 (Croxall+, 2015)
J/ApJ/700/654 : Keck spectroscopy of extragalactic HII regions (Esteban+ 2009)
J/AJ/136/2563 : HI Nearby Galaxy Survey, THINGS (Walter+, 2008)
J/A+A/441/981 : HII regions in 5 spiral galaxies (Bresolin+, 2005)
J/A+A/422/511 : Oxygen abundance in M101 HII regions (Cedres+, 2004)
J/A+A/391/809 : HII regions in NGC 5457 and NGC 4395 (Cedres+, 2002)
J/AJ/104/92 : HII Regions Properties in M101 (Scowen+ 1992)
J/ApJS/73/661 : H II regions in M 101 (Hodge+ 1990)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- HIIid HII Region; Galaxy ± offsets in RA/DE
21- 22 I2 h RAh Hour of Right Ascension (J2000)
24- 25 I2 min RAm Minute of Right Ascension (J2000)
27- 30 F4.1 s RAs Second of Right Ascension (J2000)
32 A1 --- DE- Sign of Declination (J2000)
33- 34 I2 deg DEd Degree of Declination (J2000)
36- 37 I2 arcmin DEm Arcminute of Declination (J2000)
39- 43 F5.2 arcsec DEs Arcsecond of Declination (J2000)
45- 47 I3 deg PA Slit position angle
49- 50 I2 arcsec AP [2/21] Extraction aperture along slit
52- 56 F5.3 --- RgR25 [0.01/1.1] Deprojected HII distance
from galaxy center (1)
58 I1 --- dOIII [0/1] 3σ [OIII] 4363A detection
60 I1 --- dNII [0/1] 3σ [NII] 5755A detection
62 I1 --- dSIII [0/1] 3σ [SIII] 6312A detection
64 I1 --- dOII [0/1] 3σ [OII] 7330A detection
66 I1 --- dSII [0/1] 3σ [SII] 6717A/6731A detection
68 I1 --- WR [0/1] Detection of Wolf-Rayet features
70 I1 --- HeII [0/1] 3σ narrow HeII 4686A detection
72- 76 A5 --- AltID Alternative HII Region Name (2)
77 A1 --- --- [,]
78- 80 A3 --- --- [NGC]
81- 84 I4 --- NGC ? NGC identification of complex where
the HII region is located
--------------------------------------------------------------------------------
Note (1): In units of the 25th mag isophotal radius; RC3
(de Vaucouleurs+, 1991, Cat. VII/155)
Note (2): Alternative name from Hodge+ 1990, J/ApJS/73/661;
H# = in Simbad in Simbad.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- HIIid HII Region; Galaxy ± offsets in RA/DE
21- 30 A10 --- Species Species
32- 35 I4 0.1nm lambda [3726/9546]? Species Wavelength in Angstroms
37 A1 --- f_Flux Flag on Flux (1)
39- 49 F11.5 --- Flux [0/33116] Line flux in units of Hβ=1
51- 60 F10.5 --- e_Flux [0/12]? Uncertainty in Flux
--------------------------------------------------------------------------------
Note (1): Flag as follows:
< = Flux ratio is an upper limit (in units of Hβ=1)
e = Extinction Correction for Hβ Flux, C(Hbeta) [no units].
f = Hβ Flux, F(Hbeta), in units of 10-17 ergs/s/cm2.
i = Equivalent Width in units of Angstroms.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- HIIid HII Region; Galaxy ± offsets in RA/DE
21- 25 I5 K Te([OII])1 [7010/14540]? Measured Electron temperature
in [OII] region
27- 30 I4 K e_Te([OII])1 ? Uncertainty in Te([OII])1
32- 36 I5 K Te([OIII])1 [7420/14220]? Measured Electron temperature
in [OIII] region
38- 40 I3 K e_Te([OIII])1 ? Uncertainty in Te([OIII])1
42- 46 I5 K Te([NII])1 [6300/11200]? Measured Electron temperature
in [NII] region
48- 51 I4 K e_Te([NII])1 ? Uncertainty in Te([NII])1
53- 57 I5 K Te([SIII])1 [5800/16080]? Measured Electron temperature
in [SIII] region
59- 62 I4 K e_Te([SIII])1 ? Uncertainty in Te([SIII])1
64- 66 I3 cm-3 Ne1 [4/270]? Measured Electron density (cm-3)
68- 70 I3 cm-3 e_Ne1 ? Uncertainty in Ne1
72- 76 I5 K Te([OII])2 [6300/12720] Adopted Electron temperature
in [OII] region
78- 81 I4 K e_Te([OII])2 Uncertainty in Te([OII])2
83- 87 I5 K Te([OIII])2 [5230/14220] Adopted Electron temperature
in [OIII] region
89- 92 I4 K e_Te([OIII])2 Uncertainty in Te([OIII])2
94- 98 I5 K Te([NII])2 [6300/12720] Adopted Electron temperature
in [NII] region
100-103 I4 K e_Te([NII])2 Uncertainty in Te([NII])2
105-109 I5 K Te([SIII])2 [5600/16080] Adopted Electron temperature
in [SIII] region
111-114 I4 K e_Te([SIII])2 Uncertainty in Te([SIII])2
116-118 I3 cm-3 Ne2 [100/272]? Adopted Electron density
120-122 I3 cm-3 e_Ne2 ? Uncertainty in Ne2
124-128 F5.2 10-5 O+/H+ [2.9/47.1] Abundance ratio O+/H+
130-133 F4.2 10-5 e_O+/H+ Uncertainty in O+/H+
135-139 F5.2 10-5 O++/H+ [1.8/24.4] Abundance ratio O++/H+
141-145 F5.3 10-5 e_O++/H+ Uncertainty in O++/H+
147-151 F5.3 [-] 12+log(O/H) [7.8/8.8] Oxygen abundance, 12+log(O/H)
153-157 F5.3 [-] e_12+log(O/H) Uncertainty in 12+log(O/H)
159-163 F5.2 10-6 N+/H+ [1.1/84] Abundance ratio N+/H+
165-169 F5.2 10-6 e_N+/H+ Uncertainty in N+/H+
171-175 F5.3 --- N(ICF) [1/5] Nitrogen ionization correction factor
177-181 F5.3 --- e_N(ICF) Uncertainty in N(ICF)
183-188 F6.3 [-] log(N/O) [-1.5/-0.5] Nitrogen-to-oxygen
abundance ratio
190-194 F5.3 [-] e_log(N/O) Uncertainty in log(N/O)
196-200 F5.3 [-] 12+log(N/H) [6.3/8] Nitrogen abundance, 12+log(N/H)
202-206 F5.3 [-] e_12+log(N/H) Uncertainty in 12+log(N/H)
208-212 F5.2 10-7 S+/H+ [2.9/66.4] Abundance ratio S+/H+
214-217 F4.2 10-7 e_S+/H+ Uncertainty in S+/H+
219-223 F5.1 10-7 S++/H+ [6.2/184.4] Abundance ratio S++/H+
225-228 F4.1 10-7 e_S++/H+ Uncertainty in S++/H+
230-234 F5.3 --- S(ICF) [1/3] Sulfur ionization correction factor
236-240 F5.3 --- e_S(ICF) Uncertainty in S(ICF)
242-247 F6.3 [-] log(S/O) [-1.9/-1] Sulfur-to-oxygen abundance ratio
249-253 F5.3 [-] e_log(S/O) Uncertainty in log(S/O)
255-259 F5.3 [-] 12+log(S/H) [6/7.5] Sulfur abundance, 12+log(S/H)
261-265 F5.3 [-] e_12+log(S/H) Uncertainty in 12+log(S/H)
267-271 F5.2 10-6 Ne++/H+ [1.8/35.1]? Abundance ratio Ne++/H+
273-276 F4.1 10-6 e_Ne++/H+ ? Uncertainty in Ne++/H+
278-282 F5.2 --- Ne(ICF) [1/14] Neon ionization correction factor
284-288 F5.3 --- e_Ne(ICF) Uncertainty in Ne(ICF)
290-295 F6.3 [-] log(Ne/O) [-1.2/-0.3]? Neon-to-oxygen abundance ratio
297-301 F5.3 [-] e_log(Ne/O) ? Uncertainty in log(Ne/O)
303-307 F5.3 [-] 12+log(Ne/H) [7.1/8.2]? Neon abundance, 12+log(Ne/H)
309-313 F5.3 [-] e_12+log(Ne/H) ? Uncertainty in 12+log(Ne/H)
315-319 F5.2 10-7 Ar++/H+ [0.7/26.6]? Abundance ratio Ar++/H+
321-324 F4.2 10-7 e_Ar++/H+ ? Uncertainty in Ar++/H+
326-329 F4.2 --- Ar(ICF) [1/5] Argon ionization correction factor
331-334 F4.2 --- e_Ar(ICF) Uncertainty in Ar(ICF)
336-341 F6.3 [-] log(Ar/O) [-3/-1.8]? Argon-to-oxygen abundance ratio
343-347 F5.3 [-] e_log(Ar/O) ? Uncertainty in log(Ar/O)
349-353 F5.3 [-] 12+log(Ar/H) [5.1/6.8]? Argon abundance, 12+log(Ar/H)
355-359 F5.3 [-] e_12+log(Ar/H) ? Uncertainty in 12+log(Ar/H)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Berg et al. I. NGC628. 2015ApJ...806...16B 2015ApJ...806...16B Cat. J/ApJ/806/16
Croxall et al. II. NGC5194. 2015ApJ...808...42C 2015ApJ...808...42C Cat. J/ApJ/808/42
Croxall et al. III. NGC5457. 2016ApJ...830....4C 2016ApJ...830....4C This catalog
Berg et al. IV. NGC3184. 2020ApJ...893...96B 2020ApJ...893...96B Cat. J/ApJ/893/96
Skillman et al. V. M101. 2020ApJ...894..138S 2020ApJ...894..138S
Rogers et al. VI. NGC2403. 2021ApJ...915...21R 2021ApJ...915...21R Cat. J/ApJ/915/21
Rogers et al. VII. M33. 2022ApJ...939...44R 2022ApJ...939...44R Cat. J/ApJ/939/44
Berg et al. VIII. M101. 2024ApJ...971...87B 2024ApJ...971...87B
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 03-Jan-2017