J/ApJ/735/71 Oxygen abundances in outlying HII regions (Werk+, 2011)
Metal transport to the gaseous outskirts of galaxies.
Werk J.K., Putman M.E., Meurer G.R., Santiago-Figueroa N.
<Astrophys. J., 735, 71 (2011)>
=2011ApJ...735...71W 2011ApJ...735...71W
ADC_Keywords: Abundances ; Galaxies, nearby ; H II regions ;
Photometry, H-alpha ; Photometry, CCD ; Spectroscopy
Keywords: galaxies: abundances - galaxies: evolution - H II regions -
ISM: kinematics and dynamics
Abstract:
We present a search for outlying HII regions in the extended gaseous
outskirts of nearby (D<40Mpc) galaxies and subsequent multi-slit
spectroscopy used to obtain the HII region nebular oxygen abundances.
The galaxies in our sample have extended HI disks and/or
interaction-related HI features that extend well beyond their primary
stellar components. We report oxygen abundance gradients out to 2.5
times the optical radius for these galaxies which span a range of
morphologies and masses. We analyze the underlying stellar and neutral
HI gas distributions in the vicinity of the HII regions to understand
the physical processes that give rise to the observed metal
distributions in galaxies. These measurements, for the first time,
convincingly show flat abundance distributions out to large radii in a
wide variety of systems and have broad implications for galaxy
chemodynamical evolution.
Description:
In 2005 April, over the course of four clear nights, we imaged 27
galaxies from the HI Rogues catalog (Hibbard et al.
2001ASPC..240..657H 2001ASPC..240..657H) in Hα and R-band continuum with the MDM
2.4m Hiltner telescope.
In the spring of 2008, we obtained multi-slit spectra of ∼100 HII
regions associated with the 13 HI Rogues showing emission-line dots
(ELdots) using the Gemini-North Multi-Object Spectrograph (GMOS-N).
Over the course of three observing runs, one at the MDM 2.4m in the
winter of 2007, one at the Keck 10m in the spring of 2010, and one at
the Shane 3m telescope at Lick Observatory in the spring of 2011, we
obtained longslit, low-resolution spectra for outlying HII regions in
our sample of 13 HI Rogues with extended star formation (SF).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 146 14 Properties of the galaxies in the HI Rogues sample
table4.dat 85 9 HII region properties for NGC 2146, sorted by R/R25
table5.dat 81 5 HII region properties: NGC 2782
table6.dat 80 7 HII region properties: NGC 3227
table7.dat 85 12 HII region properties: NGC 3239
table8.dat 80 11 HII region properties: NGC 3310
table9.dat 80 16 HII region properties: NGC 3359
table10.dat 80 6 HII region properties: NGC 3432
table11.dat 80 9 HII region properties: NGC 3718
table12.dat 80 8 HII region properties: NGC 3893
table13.dat 80 10 HII region properties: NGC 5774/5
table14.dat 80 6 HII region properties: NGC 6239
table15.dat 80 5 HII region properties: UGC 5288
table16.dat 80 4 HII region properties: UGC 9562
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See also:
VIII/77 : HI spectral properties of galaxies (Springob+, 2005)
J/AJ/139/279 : Outlying HII regions in HI-selected galaxies (Werk+, 2010)
J/ApJS/190/233 : Spectroscopy & abundances of SINGS galaxies (Moustakas+, 2010)
J/ApJ/695/580 : Oxygen abundance in M83 (Bresolin+, 2009)
J/ApJS/165/307 : SINGG I. (Meurer+, 2006)
J/ApJS/164/81 : Spectrophotometry of nearby galaxies (Moustakas+, 2006)
J/ApJ/636/214 : HII regions in dwarf irregular galaxies (van Zee+, 2006)
J/MNRAS/361/1063 : Oxygen abundances of HII regions (Perez-Montero+, 2005)
J/A+A/422/511 : Oxygen abundance in M101 HII regions (Cedres+, 2004)
J/ApJS/153/429 : SDSS strong emission line HII galaxies (Kniazev+, 2004)
J/A+A/414/23 : CCD Hα and R photometry of 334 galaxies (James+, 2004)
J/A+A/393/389 : Hα in HII regions in spiral galaxies (Marquez+, 2002)
J/A+A/370/765 : HI synthesis observations in UMa cluster (Verheijen+, 2001)
J/ApJ/510/104 : Ionizing Stars of Extragalactic H II Regions (Bresolin+ 1999)
J/ApJS/105/93 : H II Regions in Nearby Seyfert Galaxies (Evans+ 1996)
http://www.nrao.edu/astrores/HIrogues/ : online HI Rogues catalog
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Gal Galaxy name (NGC or UGC)
10- 11 I2 h RAh Hour of right ascension (J2000)
13- 14 I2 min RAm Minute of right ascension (J2000)
16- 19 F4.1 s RAs Second of right ascension (J2000)
21 A1 --- DE- Sign of declination (J2000)
22- 23 I2 deg DEd Degree of declination (J2000)
25- 26 I2 arcmin DEm Arcminute of declination (J2000)
28- 31 F4.1 arcsec DEs Arcsecond of declination (J2000)
33- 37 F5.2 Mpc Dist Redshift-independent distance from NED
39- 43 F5.2 kpc R25 Length of the 25th magnitude elliptical
isophote (R25) semimajor axis
45- 49 F5.3 mag E(B-V) Color excess from Schlegel et al.
(1998ApJ...500..525S 1998ApJ...500..525S)
51- 54 F4.2 [-] (O/H) Average oxygen abundance as 12+log(O/H)
56 I1 --- r_(O/H) (O/H) reference (1)
58- 61 F4.2 --- [NII]/Ha Ratio [NII]λ6583/Hα
63 I1 --- r_[NII]/Ha Reference for [NII]/Ha (1)
65- 75 A11 --- HIMorph HI morphology code from the HI Rogues
catalog (2)
77- 80 F4.1 arcsec Beam1 Beam size of HI observation
81 A1 --- --- [x]
82- 85 F4.1 arcsec Beam2 Beam size of HI observation
87-105 A19 --- Auth HI reference author's name(s)
107-125 A19 --- BibCode Bibcode for HI reference
127-133 F7.5 10+10Msun M* Stellar mass (3)
135-139 F5.3 10+10Msun MHI HI mass for the galaxy (4)
141-146 F6.4 Msun/yr SFR Derived SFR from the total Hα
luminosity obtained from the MDM 2.4m images
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Note (1): Oxygen abundance reference as follows:
1 = Moustakas & Kennicutt (2006, Cat. J/ApJS/164/81): strong-line R23
abundances and [NII]/Hα ratios from integrated spectroscopy.
2 = Lisenfeld et al. (2008ApJ...685..181L 2008ApJ...685..181L): strong-line R23 abundances and
[NII]/Hα ratios from one HII region at 0.8xR25.
3 = Martin & Roy (1995ApJ...445..161M 1995ApJ...445..161M): average of R23 oxygen abundances and
[NII]/Hα ratios for disk HII regions located between 4 and 9.5kpc
in projected distance from the optical center.
4 = Marquez et al. (2002, Cat. J/A+A/393/389): average of strong-line
[NII]/Hα abundances and ratios (Pettini & Pagel
2004MNRAS.348L..59P 2004MNRAS.348L..59P) for a number of disk HII regions.
5 = van Zee & Haynes (2006, Cat. J/ApJ/636/214): average strong-line R23
oxygen abundances and [NII]/Hα ratios for six HII regions
within R25.
6 = Shi et al. (2005A&A...437..849S 2005A&A...437..849S): average strong-line R23 oxygen
abundances and [NII]/Hα ratios for HII regions within R25.
Note (2): Morphologies are:
mMR = minor merger remnants;
E-Sp = interacting doubles, only one with HI;
Sp+-Sp+ = interacting doubles, both with HI, both with tails;
H Ic = detached HI clouds;
mM = minor mergers;
WARP = galaxies with two-sided warps;
Sp0-Sp0 = interacting doubles, both with HI, no tails;
ENVL = galaxies with extended HI envelopes
Note (3): Stellar masses derived from B-, V-, and sometimes R-band photometry
and the luminosity/color and stellar mass functions of Bell et al.
(2003ApJS..149..289B 2003ApJS..149..289B).
Note (4): HI masses for the galaxy, obtained from the literature (see
reference in column "BibCode") and corrected for the galaxy distances
we use in column "R25" of this table.
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Byte-by-byte Description of file: table1[0-6].dat table[4-9].dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Gal Galaxy name (NGC or UGC)
10- 11 I2 --- ID HII region number (slit mask ID)
13- 14 I2 h RAh Hour of right ascension (J2000)
16- 17 I2 min RAm Minute of right ascension (J2000)
19- 22 F4.1 s RAs Second of right ascension (J2000)
24 A1 --- DE- Sign of declination (J2000)
25- 26 I2 deg DEd Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 34 F4.1 arcsec DEs Arcsecond of declination (J2000)
36- 38 F3.1 --- R/R25 Projected distance from the 25th magnitude
elliptical isophote
40- 44 F5.2 kpc Rproj Projected distance from the galaxy center
46- 50 F5.2 aW/m2 FHa Hα flux from MDM 2.4m images
(in units of 10-15erg/s/cm2)
52- 55 F4.2 aW/m2 e_FHa FHa uncertainty
57 A1 --- l_Rmag Limit flag on Rmag (1)
58- 62 F5.2 mag Rmag R-band apparent AB magnitude from
MDM 2.4m images (1)
64- 67 F4.2 mag e_Rmag Rmag uncertainty (1)
69- 71 I3 --- [OII] ? Reddening corrected [OII]3727 emission-line
strength (2)
73- 75 I3 --- [OIII] ? Reddening corrected [OIII]4959 and
λ5007 summed emission-line strength (2)
77- 80 F4.2 [-] (O/H) Strong-line oxygen abundance as 12+log(O/H) (3)
81 A1 --- f_(O/H) [*] (O/H) from [NII]/Hα method (4)
82- 85 F4.2 [-] (O/H)2 ? Second value of the 12+log(O/H) oxygen
abundance (upper-branch R23) (3)
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Note (1): We use the 5σ limiting magnitude for a point source in each
image when an HII region is undetected in the R band.
Note (2): The reddening-corrected [OII]λλ3727 and
[OIII]λ4959 and λ5007 summed emission-line strengths,
relative to Hβ of 100. Reddening correction was done for case B
recombination with T=10000K and ne=100cm-3, where
Hα/Hβ=2.86 and Hγ/Hβ=0.459.
Note (3): The strong-line oxygen abundance, 12+log(O/H), from the M91
calibration of the R23 relation described in Section 4. In cases where
there is one value, we have used the [NII]/Hα to break the R23
degeneracy. In cases where there are two values, the [NII]/Hα
either falls in the ambiguous range (0.05-0.08) or was not available.
The first value is the lower-branch R23 oxygen abundance, the second
is the upper-branch R23 oxygen abundance. The error associated with
strong-line abundances is notoriously large, ranging from 0.15 to
0.2dex, as discussed in Section 4.
Note (4): In a few cases (for just NGC 2146 and NGC 2782), values for
12+log(O/H) marked with an asterisk indicate that the GMOS multi-slit
spectra were red enough to obtain Hα and [NII]6583, but not the
blue lines. In these few cases, we used the [NII]/Hα method from
Pettini & Pagel (2004MNRAS.348L..59P 2004MNRAS.348L..59P) to determine the oxygen
abundance. These values cannot be compared directly with R23 values
because of systematic offsets of the calibration methods.
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Nomenclature Notes:
Tables 4-16: HII regions are <[WPM2011] {Gal} NN> in Simbad
History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 16-Apr-2013