J/ApJ/842/97 Spectroscopic obs. of 413 HII regions in M33 (Lin+, 2017)
Spectroscopic observation and analysis of H II regions in M33 with MMT:
temperatures and oxygen abundances.
Lin Z., Hu N., Kong X., Gao Y., Zou H., Wang E., Cheng F., Fang G., Lin L.,
Wang J.
<Astrophys. J., 842, 97 (2017)>
=2017ApJ...842...97L 2017ApJ...842...97L
ADC_Keywords: Spectra, optical ; H II regions ; Abundances ; Radial velocities
Equivalent widths ; Cross identifications
Keywords: galaxies: abundances; galaxies: evolution; galaxies: individual (M33);
galaxies: ISM; galaxies: spiral; H II regions
Abstract:
The spectra of 413 star-forming (or H II) regions in M33 (NGC 598)
were observed using the multifiber spectrograph of Hectospec at the
6.5m Multiple Mirror Telescope. Using this homogeneous spectra sample,
we measured the intensities of emission lines and some physical
parameters, such as electron temperatures, electron densities, and
metallicities. Oxygen abundances were derived via the direct method
(when available) and two empirical strong-line methods, namely, O3N2
and N2. At the high-metallicity end, oxygen abundances derived from
the O3N2 calibration were higher than those derived from the N2 index,
indicating an inconsistency between O3N2 and N2 calibrations. We
present a detailed analysis of the spatial distribution of gas-phase
oxygen abundances in M33 and confirm the existence of the axisymmetric
global metallicity distribution that is widely assumed in the
literature. Local variations were also observed and subsequently
associated with spiral structures to provide evidence of radial
migration driven by arms. Our O/H gradient fitted out to 1.1 R25
resulted in slopes of -0.17±0.03, -0.19±0.01, and -0.16±0.17dex
R25-1, utilizing abundances from O3N2, N2 diagnostics, and a
direct method, respectively.
Description:
The observations discussed in this paper were obtained on the nights
of 2013 October 9, 12, and 15, using the Hectospec fiber-fed
spectrograph at the Multiple Mirror Telescope (MMT) --wavelength range
of 3650-9200Å with a resolution of ∼6Å.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 66 413 Sample of HII regions observed in M33
table2.dat 257 413 Reddening-corrected emission line fluxes of
HII regions in M33
table3.dat 124 413 Physical conditions and metallicity of
HII regions in M33
--------------------------------------------------------------------------------
See also:
J/AJ/110/2739 : H-alpha emitting regions in M33 (Calzetti+ 1995)
J/A+AS/123/159 : IRON Project. XXII. C and O radiative rates (Galavis+ 1997)
J/ApJS/123/311 : Excitation rate coefficients for O III (Aggarwal+, 1999)
J/ApJS/120/247 : Supernova remnants in M33 (Gordon+, 1999)
J/PASP/111/685 : HII regions of M33. II. (Hodge+, 1999)
J/ApJS/173/185 : GALEX ultraviolet atlas of nearby galaxies (Gil de Paz+, 2007)
J/ApJS/174/366 : Chandra ACIS survey of M33 (ChaSeM33) (Plucinsky+, 2008)
J/ApJ/675/1213 : Abundances in M33 HII regions (Rosolowsky+, 2008)
J/ApJ/700/654 : Keck spectroscopy of extragalactic HII regions (Esteban+ 2009)
J/A+A/512/A63 : Abundances of M33 HII regions (Magrini+, 2010)
J/ApJS/188/32 : Breit-Pauli transition probabilities for SII (Tayal+, 2010)
J/A+A/552/A140 : SEDs of M33 HII regions (Relano+, 2013)
J/A+A/559/A114 : Updated O3N2 and N2 abundance indicators (Marino+, 2013)
J/A+A/586/A37 : M33 center and BCLMP302 [CII] spectroscopy (Mookerjea+, 2016)
J/A+A/595/A43 : Photometry of 119 HII regions in M33 (Relano+, 2016)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Identification of HII region (1)
5- 17 A13 --- Name ? HII region name from published catalog (2)
19- 19 I1 h RAh [1] Hour of Right Ascension (J2000)
21- 22 I2 min RAm [32/35] Minute of Right Ascension (J2000)
24- 28 F5.2 s RAs Second of Right Ascension (J2000)
30- 30 A1 --- DE- [+] Sign of Declination (J2000)
32- 33 I2 deg DEd [30/31] Degree of Declination (J2000)
35- 36 I2 arcmin DEm Arcminute of Declination (J2000)
38- 41 F4.1 arcsec DEs Arcsecond of Declination (J2000)
43- 47 F5.3 kpc R [0.1/8] Physical distance to the center
of M33 (3)
49- 53 F5.3 --- R/R25 [0.02/1.1] R to R25 ratio (4)
55- 60 F6.2 deg PA Position angle (5)
62- 62 I1 --- FO3 [1/2]? Flag of [OIII]4363 detection (6)
64- 64 I1 --- FN2 [1/2]? Flag of [NII]5755 detection (6)
66- 66 I1 --- Fn [1/3] Flag of the observed night (7)
--------------------------------------------------------------------------------
Note (1): IDs of HII regions sorted by right ascension. A total of 10 regions
(ID=72, 148, 150, 160, 246, 324, 327, 397, 403, 409) do not have
significant [OIII]5007 or [NII]6583 detections. A total of 18 HII
regions with the following IDs lie above the Kauffmann+
(2003MNRAS.346.1055K 2003MNRAS.346.1055K) line at the BPT diagram, indicating that they
are likely not star-forming dominated regions: 45, 79, 107, 151, 164,
217, 224, 233, 237, 252, 265, 291, 308, 322, 357, 379, 389, 398.
Note (2): Abbreviations as below:
BCLMP = Boulesteix et al. (1974A&A....37...33B 1974A&A....37...33B ; in Simbad);
VGV86 = Viallefond et al. (1986A&AS...64..237V 1986A&AS...64..237V ; in Simbad);
CPSDP = Courtes et al. (1987A&A...174...28C 1987A&A...174...28C ; in Simbad);
GDK99 = Gordon et al. (1999, J/ApJS/120/247 ; <[GDK99] NNN> in Simbad);
HBW = Hodge et al. (1999, J/PASP/111/685 ; in Simbad).
Note (3): Physical distances to the center of M33 located at
RAJ2000=1:33:50.89, DEJ2000=30:39:36.8
(Plucinsky+ 2008, J/ApJS/174/366). We assumed a distance
to M33 of 878kpc, an inclination of 56arcdeg
(Zaritsky+ 1989AJ.....97...97Z 1989AJ.....97...97Z), and a position angle
of 23arcdeg (Zaritsky+ 1989AJ.....97...97Z 1989AJ.....97...97Z).
Note (4): Assumed an R25 of 28.2 arcmin (de Vaucouleurs 1959ApJ...130..728D 1959ApJ...130..728D).
Note (5): Position angles are de-projected angles on the disk of M33, measured
from north to east.
Note (6): Numbers indicate the detected quality of two auroral Lines.
Code as follows:
1 = an emission line with a significant detection (S/N≥3) but
without a well-defined profile,
2 = an emission line with not only a significant detection but also a
well-defined profile.
Note (7): Observation nights of each object. "1", "2", and "3" indicate the
nights of 2013 October 9, 12, and 15, respectively.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Identification of HII region
5- 10 F6.3 --- [OII]3727 [0.1/10.5]? Emission line flux (8)
12- 16 F5.3 --- e_[OII]3727 [0.01/0.3]? Uncertainty in flux
18- 22 F5.3 --- [NeIII]3869 [0.05/1.4]? Emission line flux (8)
24- 28 F5.3 --- e_[NeIII]3869 [0.004/0.3]? Uncertainty in flux
30- 34 F5.3 --- Hdelta4102 [0.1/1.2]? Emission line flux (8)
36- 40 F5.3 --- e_Hdelta4102 [0.004/0.3]? Uncertainty in flux
42- 46 F5.3 --- Hgamma4340 [0.3/1]? Emission line flux (8)
48- 52 F5.3 --- e_Hgamma4340 [0.008/0.2]? Uncertainty in flux
54- 58 F5.3 --- [OIII]4363 [0.002/0.4]? Emission line flux (8)
60- 64 F5.3 --- e_[OIII]4363 [0.001/0.05]? Uncertainty in flux
66- 70 F5.3 --- [OIII]4959 [0.01/3]? Emission line flux (8)
72- 76 F5.3 --- e_[OIII]4959 [0.001/0.04]? Uncertainty in flux
78- 82 F5.3 --- [OIII]5007 [0.04/9]? Emission line flux (8)
84- 88 F5.3 --- e_[OIII]5007 [0.002/0.2]? Uncertainty in flux
90- 94 F5.3 --- [NII]5755 [0.001/0.3]? Emission line flux (8)
96-100 F5.3 --- e_[NII]5755 [0/0.06]? Uncertainty in flux
102-106 F5.3 --- HeI5876 [0.02/0.6]? Emission line flux (8)
108-112 F5.3 --- e_HeI5876 [0.001/0.07]? Uncertainty in flux
114-118 F5.3 --- [OI]6300 [0.005/1.1]? Emission line flux (8)
120-124 F5.3 --- e_[OI]6300 [0/0.1]? Uncertainty in flux
126-130 F5.3 --- [NII]6548 [0.01/0.6]? Emission line flux (8)
132-136 F5.3 --- e_[NII]6548 [0/0.03]? Uncertainty in flux
138-142 F5.3 --- Halpha6563 [1.3/3]Emission line flux (8)
144-148 F5.3 --- e_Halpha6563 [0.02/0.1] Uncertainty in flux
150-154 F5.3 --- [NII]6583 [0.04/1.5]? Emission line flux (8)
156-160 F5.3 --- e_[NII]6583 [0.001/0.08]? Uncertainty in flux
162-166 F5.3 --- [SII]6717 [0.004/2] Emission line flux (8)
168-172 F5.3 --- e_[SII]6717 [0.001/0.08] Uncertainty in flux
174-178 F5.3 --- [SII]6731 [0.008/1.7]? Emission line flux (8)
180-184 F5.3 --- e_[SII]6731 [0.001/0.08]? Uncertainty in flux
186-190 F5.3 --- [ArIII]7135 [0.005/0.2]? Emission line flux (8)
192-196 F5.3 --- e_[ArIII]7135 [0/0.06]? Uncertainty in flux
198-202 F5.3 --- [OII]7320 [0.005/0.2]? Emission line flux (8)
204-208 F5.3 --- e_[OII]7320 [0/0.04]? Uncertainty in flux
210-214 F5.3 --- [OII]7330 [0.005/0.3]? Emission line flux (8)
216-220 F5.3 --- e_[OII]7330 [0/0.03]? Uncertainty in flux
222-228 F7.1 10-20W/m2 Hbeta4861 [9/13572] Hbeta flux; 1e-17erg/s/cm2
230-235 F6.1 10-20W/m2 e_Hbeta4861 [0.3/1313] Uncertainty of Hbeta4861
237-242 F6.1 0.1nm EW(Hbeta) [2/2405]? Equivalent width of Hbeta;
Angstrom (9)
244-249 F6.4 mag E(B-V) [0.0001/1.6]? Color excess
251-257 F7.2 km/s RVel [-117/119] Radial velocity (10)
--------------------------------------------------------------------------------
Note (8): In units of Hbeta=1.
Note (9): Hbeta emission line equivalent widths corrected for stellar
absorption. Two HII regions (ID=160, 350) have negative local
continuum fluxes, resulting in incorrect EWs of Hbeta. These
EWs are excluded from this table.
Note (10): Radial velocity for each region. System velocity of M33, assuming a
value of -179km/s (de Vaucouleurs+ 1991, VII/155),
has been subtracted.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Seq Identification of HII region
5- 9 I5 K Te[OIII] [6600/68700]? Electron temperature derived
from [OIII] auroral line
11- 15 I5 K e_Te[OIII] [100/21500]? Lower error of Te[OIII]
17- 21 I5 K E_Te[OIII] [100/46600]? Upper error of Te[OIII]
23- 27 I5 K Te[NII] [6400/95100]? Electron temperature derived
from [NII] auroral line
29- 33 I5 K e_Te[NII] [300/24000]? Lower error of Te[NII]
35- 39 I5 K E_Te[NII] [300/50000]? Upper error of Te[NII]
41- 44 I4 cm-3 ne [1/1549]? Electron density
46- 48 I3 cm-3 e_ne [0/382]? Lower error of ne
50- 52 I3 cm-3 E_ne [12/898]? Upper error of ne
54- 58 F5.3 --- ZO[Te] [7/9.1]? Oxygen abundance derived from Te method
60- 64 F5.3 --- e_ZO[Te] [0.01/0.3]? Lower error of ZO[Te]
66- 70 F5.3 --- E_ZO[Te] [0.01/0.7]? Upper error of ZO[Te]
72- 76 F5.3 --- ZO[O3N2] [8.1/8.7]? Oxygen abundance derived
from O3N2 calibration (11)
78- 82 F5.3 --- e_ZO[O3N2] [0.002/0.05]? Lower error of ZO[O3N2]
84- 88 F5.3 --- E_ZO[O3N2] [0.002/0.08]? Upper error of ZO[O3N2]
90- 94 F5.3 --- ZO[N2] [8/8.7]? Oxygen abundance derived
from N2 calibration (12)
96-100 F5.3 --- e_ZO[N2] [0.004/0.2]? Lower error ZO[N2]
102-106 F5.3 --- E_ZO[N2] [0.003/0.1]? Upper error ZO[N2]
108-112 F5.3 --- ZN[Te] [6.4/8]? Nitrogen abundance derived from
Te method
114-118 F5.3 --- e_ZN[Te] [0.03/0.3]? Lower error ZN[Te]
120-124 F5.3 --- E_ZN[Te] [0.03/0.8]? Upper error ZN[Te]
--------------------------------------------------------------------------------
Note (11): Oxygen abundance derived from O3N2 index using calibration from
Marino+ (2013, J/A+A/559/A114).
The systematic uncertainty of this calibration is 0.18.
Note (12): Oxygen abundance derived from N2 index using calibration from
Marino+ (2013, J/A+A/559/A114).
The systematic uncertainty of this calibration is 0.16.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 31-Jan-2018