J/ApJ/636/214 HII regions in dwarf irregular galaxies (van Zee+, 2006)
Oxygen and nitrogen in isolated dwarf irregular galaxies.
van Zee L., Haynes M.P.
<Astrophys. J., 636, 214-239 (2006)>
=2006ApJ...636..214V 2006ApJ...636..214V
ADC_Keywords: H II regions ; Abundances ; Galaxies, optical
Keywords: galaxies: abundances - galaxies: dwarf - galaxies: evolution -
galaxies: irregular - H II regions
Abstract:
We present long-slit optical spectroscopy of 67 HII regions in 21
dwarf irregular galaxies to investigate the enrichment of oxygen,
nitrogen, neon, sulfur, and argon in low-mass galaxies. Oxygen
abundances are obtained via direct detection of the
temperature-sensitive emission lines for 25 HII regions; for the
remainder of the sample, oxygen abundances are estimated from
strong-line calibrations. The direct abundance determinations are
compared to the strong-line abundance calibrations of both McGaugh
(1991ApJ...380..140M 1991ApJ...380..140M) and Pilyugin (2000A&A...362..325P 2000A&A...362..325P).
Description:
Optical spectroscopic observations of HII regions in 21 dwarf
irregular galaxies were obtained with the Double Spectrograph on the
5m Palomar telescope during several observing runs between 1999
January and 2002 April.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 110 21 Global galaxy parameters
table2.dat 55 31 Observing log
table3.dat 163 66 HII region line strengths
table4.dat 95 67 HII region line ratios
table5.dat 101 67 HII region abundances
table6.dat 68 19 Parameters of additional dwarf irregular galaxies
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See also:
J/AJ/116/2805 : H II regions in spiral galaxies (Van Zee+, 1998)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Galaxy Galaxy name
14- 15 I2 h RAh Hour of Right Ascension (J2000.0)
17- 18 I2 min RAm Minute of Right Ascension (J2000.0)
20- 23 F4.1 s RAs Second of Right Ascension (J2000.0)
25 A1 --- DE- Sign of the Declination (J2000.0)
26- 27 I2 deg DEd Degree of Declination (J2000.0)
29- 30 I2 arcmin DEm Arcminute of Declination (J2000.0)
32- 35 F4.1 arcsec DEs Arcsecond of Declination (J2000.0)
37- 43 A7 --- MType Morphological type
45- 49 F5.2 Mpc Dist Distance (1)
51- 53 I3 arcsec R25 Isophotal radius in arcsec
55- 57 F3.1 kpc R25kpc Isophotal radius in kpc
59- 64 F6.2 mag BMAG Absolute B magnitude (2)
66- 69 F4.2 mag (B-V)0 ? (B-V)0 color index (2)
71- 74 F4.2 mag e_(B-V)0 ? Error in (B-V)0
76- 78 F3.1 Sun MH/LB Mass/luminosity ratio (gas richness)
80- 83 F4.1 mag/arcsec2 mu0B ? Central surface brightness
85- 89 F5.2 [solMass] logMdyn Dynamical mass
91- 94 F4.2 --- 12+log(O/H) Oxygen abundance (3)
96- 99 F4.2 --- e_12+log(O/H) Error in 12+log(O/H)
101-105 F5.2 --- log(N/H) Nitrogen abundance (3)
107-110 F4.2 --- e_log(N/H) Error in log(N/H)
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Note (1): Distances are calculated from systemic velocities using a
Virgocentric infall model and an H0 of 75km/s/Mpc except for UGC 685
(Maiz-Apellaniz et al. 2002AJ....123.1307M 2002AJ....123.1307M), HKK97 L14 (Karachentsev
et al. 2004, Cat. J/AJ/127/2031), UGC 4483 (Dolphin et al.
2001MNRAS.324..249D 2001MNRAS.324..249D), and UGC 8651 and UGC 9240 (Karachentsev et al.
2002A&A...389..812K 2002A&A...389..812K), which have tip of the Red Giant Branch distances
in the literature.
Note (2): Colors, magnitudes, optical size, and MH/LB are from van Zee
(2000AJ....119.2757V 2000AJ....119.2757V). The absolute blue magnitudes and colors have
been corrected for Galactic extinction
Note (3): Global oxygen and nitrogen abundances are from the present study
except for UGC 3672, for which more accurate abundances are available
in the literature (van Zee et al. 1997AJ....114.2479V 1997AJ....114.2479V,
1997AJ....114.2497V 1997AJ....114.2497V).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Galaxy Galaxy name
13 A1 --- --- [/]
14 A1 --- Slit Slit number
16- 17 I2 h RAh Hour of Right Ascension (J2000.0)
19- 20 I2 min RAm Minute of Right Ascension (J2000.0)
22- 25 F4.1 s RAs Second of Right Ascension (J2000.0)
27 A1 --- DE- Sign of the Declination (J2000.0)
28- 29 I2 deg DEd Degree of Declination (J2000.0)
31- 32 I2 arcmin DEm Arcminute of Declination (J2000.0)
34- 35 I2 arcsec DEs Arcsecond of Declination (J2000.0)
37- 39 I3 deg PA Position angle
41- 48 A8 --- Run Run identification
50 I1 --- Nexp Number of exposures
51 A1 --- --- [x]
52- 55 I4 s Tint Integration time
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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- 12 A12 --- Galaxy Galaxy name (G1)
13 A1 --- --- [/]
14 A1 --- Slit Slit number
16- 19 I4 arcsec EW East-West offset from the galaxy center
(East positive) (G1)
20- 23 I4 arcsec NS North-South offset from the galaxy center
(North positive) (G1)
25- 29 F5.3 --- [OII] Relative [OII]3727+3729Å line strength (1)
31- 35 F5.3 --- e_[OII] Error in [OII]
37- 41 F5.3 --- [NeIII] ? Relative [NeIII]3869Å line strength (1)
43- 47 F5.3 --- e_[NeIII] ? Error in [NeIII]
49- 53 F5.3 --- [OIII] Relative [OIII]4959+5007 line strength (1)
55- 59 F5.3 --- e_[OIII] Error in [OIII]
61- 65 F5.3 --- [OI] ? Relative [OI]6300Å line strength (1)
67- 71 F5.3 --- e_[OI] ? Error in [OI]
73- 77 F5.3 --- [SIII] ? Relative [SIII]6312Å line strength (1)
79- 83 F5.3 --- e_[SIII] ? Error in [SIII]
85- 89 F5.3 --- Halpha Relative Hα6563Å line strength (1)
91- 95 F5.3 --- e_Halpha Error in Halpha
97-101 F5.3 --- [NII] ? Relative [NII]6548+6584 line strength (1)
103-107 F5.3 --- e_[NII] ? Error in [NII]
109-113 F5.3 --- He ? Relative He6678Å line strength (1)
115-119 F5.3 --- e_He ? Error in He
121-125 F5.3 --- [SII] Relative [SII]6717+6731Å line strength (1)
127-131 F5.3 --- e_[SII] Error in [SII]
133-137 F5.3 --- [ArIII] ? Relative [ArIII]7136Å line strength (1)
139-143 F5.3 --- e_[ArIII] ? Error in [ArIII]
145-148 F4.2 --- cHbeta Reddening coefficient CHβ
150-153 F4.2 --- e_cHbeta Error in cHbeta
155-157 I3 0.1nm EWHbeta Hβ equivalent width
159-163 F5.2 10-18W/m2 F(Hbeta) Hβ flux
(in units of 10-15ergs/s/cm2)
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Note (1): Reddening-corrected line intensities relative to Hβ.
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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- 12 A12 --- Galaxy Galaxy name (G1)
13 A1 --- --- [/]
14 A1 --- Slit [A-D] Slit number
16- 19 I4 arcsec EW East-West offset from the galaxy
center (East positive) (G1)
20- 23 I4 arcsec NS North-South offset from the galaxy
center (North positive) (G1)
25- 28 F4.2 --- [SII] The [SII] ratio (=I(6717)/I(6731)
30- 33 F4.2 --- e_[SII] Error in [SII]
35- 39 F5.1 --- [OIII] ? The [OIII] ratio
(=I(4959+5007)/I(4363))
41- 44 F4.1 --- e_[OIII] ? Error in [OIII]
46- 50 F5.3 --- log([OII]+[OIII]) log([OII]+[OIII])
52- 56 F5.3 --- e_log([OII]+[OIII]) Error in log([OII]+[OIII])
58- 63 F6.3 --- log([OIII]/[OII]) log([OIII]/[OII])
65- 69 F5.3 --- e_log([OIII]/[OII]) Error in log([OIII]/[OII])
71- 76 F6.3 --- log([NII]/[OII]) log([NII]/[OII])
78- 82 F5.3 --- e_log([NII]/[OII]) Error in log([NII]/[OII])
84- 89 F6.3 --- log([SII]/[OII]) ? log([SII]/[OII])
91- 95 F5.3 --- e_log([SII]/[OII]) ? Error in log([SII]/[OII])
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 12 A12 --- Galaxy Galaxy name (G1)
14- 17 I4 arcsec EW East-West offset from the galaxy center
(East positive) (G1)
18- 21 I4 arcsec NS North-South offset from the galaxy center
(North positive) (G1)
23- 27 I5 K Te([OIII]) Electron temperature from [OIII]
29- 32 I4 K E_Te([OIII]) ? Upper limit error in Te([OIII])
34- 37 I4 K e_Te([OIII]) ? Lower limit error in Te([OIII])
39- 42 F4.2 --- 12+log(O/H)1 Oxygen abundance from McGaugh
(1991ApJ...380..140M 1991ApJ...380..140M)
44- 47 F4.2 --- 12+log(O/H)2 Oxygen abundance from Pilyugin
(2000A&A...362..325P 2000A&A...362..325P)
49- 52 F4.2 --- 12+log(O/H) Oxygen abundance
54- 57 F4.2 --- e_12+log(O/H) Error in 12+log(O/H)
59- 63 F5.2 --- log(N/O) ? log(N/O) abundance ratio
65- 68 F4.2 --- e_log(N/O) ? Error in log(N/O)
70- 74 F5.2 --- log(Ne/O) ? log(Ne/O) abundance ratio
76- 79 F4.2 --- e_log(Ne/O) ? Error in log(Ne/O)
81- 85 F5.2 --- log(S/O) ? log(S/O) abundance ratio
87- 90 F4.2 --- e_log(S/O) ? Error in log(S/O)
92- 96 F5.2 --- log(Ar/O) ? log(Ar/O) abundance ratio
98-101 F4.2 --- e_log(Ar/O) ? Error in log(Ar/O)
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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- 9 A9 --- Galaxy Galaxy name
11- 15 F5.2 Mpc Dist Distance (1)
17- 22 F6.2 mag BMAG Absolute B magnitude (2)
24- 27 F4.2 mag (B-V)0 ? (B-V)0 color index (2)
29- 32 F4.2 mag e_(B-V)0 ? Error in (B-V)0 (2)
34- 36 F3.1 Sun MH/LB Mass/luminosity ratio (gas richness) (2)
38- 41 F4.1 --- mu0B ? Central surface brightness
43- 47 F5.2 [solMass] logMdyn ? Dynamical mass
49- 52 F4.2 --- 12+log(O/H) Oxygen abundance (2)
54- 57 F4.2 --- e_12+log(O/H) Error in 12+log(O/H)
59- 63 F5.2 --- log(N/H) Nitrogen abundance (2)
65- 68 F4.2 --- e_log(N/H) Error in log(N/H)
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Note (1): Distances are calculated from systemic velocities using a
Virgocentric infall model and an H0 of 75km/s/Mpc, except for
-- Leo A (Dohm-Palmer et al. 1998AJ....116.1227D 1998AJ....116.1227D),
-- GR 8 (Dohm-Palmer et al. 1998AJ....116.1227D 1998AJ....116.1227D), and
-- UGC 9128 (Aparicio et al. 2000AJ....119..177A 2000AJ....119..177A),
which have TRGB distances in the literature.
Note (2): Colors, magnitudes, MH/LB, and oxygen and nitrogen abundances
are from van Zee et al. (1997AJ....114.2479V 1997AJ....114.2479V, 1997AJ....114.2497V 1997AJ....114.2497V,
2005 in press).
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Global Notes:
Note (G1): [VH2006] UGC NNNNN A +XXX+YYY or [VH2006] Z 7-25 A +XXX+YYY in Simbad,
where +XXX and +YYY are the East-West and North-South offsets
(respectively) from the galaxy center and A is the slit name.
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History:
From electronic version of the journal
(End) Marianne Brouty [CDS] 30-Oct-2006