J/ApJ/655/814 HII regions in IC 342/Maffei group (Fingerhut+, 2007) ================================================================================ The extinction and distance of Maffei 2 and a new view of the IC 342/Maffei group. Fingerhut R.L., Lee H., Mccall M.L., Richer M.G. =2007ApJ...655..814F ================================================================================ ADC_Keywords: Clusters, galaxy ; H II regions ; Spectroscopy ; Radial velocities Keywords: galaxies: clusters: individual (IC 342-Maffei) - galaxies: distances and redshifts - galaxies: individual (Maffei 1, Maffei 2, IC 342) Abstract: We have obtained spectra of HII regions in the heavily obscured spiral galaxy Maffei 2. The observations have allowed for a determination of the Galactic extinction of this galaxy using a correlation between extinction and hydrogen column density observed among spiral galaxies. Description: Long-slit spectroscopic observations of two HII regions in Maffei 2 were obtained on 1997 March 2 and 3 UT with the Ritchey-Chretien spectrograph on the Mayall 4m telescope at Kitt Peak National Observatory (KPNO). Observations were optimized to detect both H{alpha} and H{beta} emission to determine the extinction toward Maffei 2. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table2.dat 124 8 Properties of HII regions in Maffei 2 and IC 342 table4.dat 124 73 Properties of HII regions sample table3.dat 75 12 Properties of the spiral galaxies hosting HII regions -------------------------------------------------------------------------------- See also: J/A+AS/124/559 : VI photometry of dwarf galaxies (Karanchentsev+ 1997) Byte-by-byte Description of file: table[24].dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 8 A8 --- Gal Galaxy name 10- 19 A10 --- [FLM2007] HII region name (+xxxx+yyyy) (1) 21- 24 I4 arcsec r Deprojected galactocentric radius (2) 26- 30 F5.1 0.1nm EWHb ?=- H{beta} equivalent width 32- 36 F5.2 --- Ha/Hb Observed H{alpha}-to-H{beta} flux ratio (3) 38- 41 F4.2 --- e_Ha/Hb ? rms uncertainty on Ha/Hb 43- 47 F5.2 [-] [O/H] Oxygen abundance log(O/H) derived from the forbidden oxygen lines 48 A1 --- n_[O/H] [a] No O line data (4) 50- 54 I5 K T Equilibrium temperature derived from [O/H] 56- 59 F4.2 --- Ha/Hb0 Intrinsic Balmer flux ratio (5) 61- 65 F5.2 --- tau Total optical depth at 1um derived from the observed and intrinsic Balmer decrements 67- 70 F4.2 --- e_tau ? rms uncertainty on tau 72- 76 F5.2 10+20cm-2 NHI Annular averaged column density of neutral hydrogen within the annulus at r 78- 81 F4.2 10+20cm-2 e_NHI ? rms uncertainty on HI 83- 86 F4.2 10+20cm-2/km/s X Conversion factor for CO intensity to H2 column density (X=N(H2)/I(CO)) (in 10^20^cm^-2^/(km/s)) 88- 92 F5.2 10+20cm-2 NH2 Annular averaged column density of molecular hydrogen within the annulus at r 94- 97 F4.2 10+20cm-2 e_NH2 ? rms uncertainty on NH2 99-103 F5.2 10+20cm-2 nH Half of the column density of hydrogen in both atomic and molecular form at r 105-108 F4.2 10+20cm-2 e_nH ? rms uncertainty on nH 110-114 F5.2 --- tauloc Extragalactic optical depth at 1um (6) 116-119 F4.2 --- e_tauloc ? rms uncertainty on tauloc 121-124 A4 --- Ref References (7) -------------------------------------------------------------------------------- Note (1): Eastward and northward offset of the H II region from the galaxy nucleus as projected on the sky, in arcseconds. Identified as [FLM2007] Gal (+xxxx+yyyy) in Simbad. Note (2): Deprojected galactocentric radius of the HII region using i and {phi} from Table 3. Note (3): corrected for underlying stellar absorption but not for Galactic reddening, assuming an equivalent width for absorption of 1.9{AA} (see McCall et al., 1985ApJS...57....1M). Note (4): a = absence of oxygen line data, resulting in the use of eq. (4) or eq. (5) to determine the temperature, and hence log(O/H). Note (5): Intrinsic Balmer flux ratio based on the HII region's equilibrium temperature and an electron density of 100cm^-3^ Note (6): Extragalactic optical depth at 1um of the HII region, i.e., the difference between the total optical depth and the Galactic optical depth. Note (7): References as follows: BK82 = Blair et al., 1982ApJ...254...50B FL07 = This study MR85 = McCall et al., 1985ApJS...57....1M KA81 = Kwitter & Aller, 1981MNRAS.195..939K RP82 = Rayo et al., 1982ApJ...255....1R SK96 = Skillman et al., 1996ApJ...462..147S SS91 = Shields & Skillman, 1991ApJ...371...82S VP88 = Vilchez et al., 1988MNRAS.235..633V -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 8 A8 --- Gal Galaxy 10 I1 --- TType Morphological stage from RC3 (VII/155) 12- 13 I2 h RAh Right ascension (J2000) 15- 16 I2 min RAm Right ascension (J2000) 18- 21 F4.1 s RAs Right ascension (J2000) 23 A1 --- DE- Declination sign (J2000) 24- 25 I2 deg DEd Declination (J2000) 27- 28 I2 arcmin DEm Declination (J2000) 30- 31 I2 arcsec DEs Declination (J2000) 32 A1 ---- r [a] a: position from Buta & McCall (1999ApJS..124...33B), else RC3 (VII/155) 34- 37 I4 km/s HRV Heliocentric radial velocity from the HI reference 38 A1 --- r_HRV [b] b: HRV from Newton (1980MNRAS.191..169N), else RC3 (Cat. VII/155) 40- 41 I2 deg i Inclination angle from the HI reference 42 A1 --- r_i [b] b: i from Newton (1980MNRAS.191..169N), else RC3 (Cat. VII/155) 44- 46 I3 deg phi Position angle from the HI reference 47 A1 --- r_phi [b] b: phi from Newton (1980MNRAS.191..169N), else RC3 (Cat. VII/155) 49- 53 F5.1 arcsec r0 Disk scale length (1) 55- 59 F5.3 mag E(B-V) ?=- Galactic reddening from Schlegel et al. (1998ApJ...500..525S) 61- 65 F5.3 --- tau ?=- Optical depth of Galactic dust at 1um calculated from E(B-V) 67- 70 A4 --- HIref Source of the HI map of the galaxy (2) 72- 75 A4 --- COref Source of the CO distribution of the galaxy (2) -------------------------------------------------------------------------------- Note (1): The radius at which the surface brightness in B drops to 1/e of its central value from Skillman et al. (1996ApJ...462..147S) (NGC 4501 and NGC 4654), Buta & McCall (1999ApJS..124...33B) (Maffei 2 and IC 342), and Zaritsky et al. (1994ApJ...420...87Z) (for all other galaxies). Note (2): References as follows: BG81 = Bosma et al., 1981A&A....93..106B HT96 = Hurt et al., 1996ApJ...466..135H KS91 = Kenney et al., 1991ApJ...366..432K KY88 = Kenney & Young, 1988ApJS...66..261K MW04 = Mason & Wilson, 2004ApJ...612..860M N80a = Newton, 1980MNRAS.191..169N N80b = Newton, 1980MNRAS.191..615N TA91 = Tilanus & Allen, 1991A&A...244....8T W88 = Warmels, 1988A&AS...72..427W WV86 = Wevers et al., 1986A&AS...66..505W YX95 = Young et al., 1995ApJS...98..219Y -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Patricia Vannier [CDS] 10-Dec-2008