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J/A+A/439/487       Nuker law fits of radio galaxies         (De Ruiter+, 2005)

Are radio galaxies and quiescent galaxies different? Results from the analysis of HST brightness profiles. De Ruiter H.R., Parma P., Capetti A., Fanti R., Morganti R., Santantonio L. <Astron. Astrophys., 439, 487-496 (2005)> =2005A&A...439..487D
ADC_Keywords: Galaxies, radio ; Redshifts Keywords: Galaxies: active - Galaxies: elliptical and lenticulars, cD - Galaxies: nuclei Abstract: We present Nuker law fits of brightness profiles of a number of radio galaxies that were observed with the HST. The data on B2 radio galaxies were described in Capetti et al. (2000A&A...362..871C), while a number of 3C galaxies with FR II radio structure were taken from the HST archive. The profiles are compared with other samples of early type galaxies, taken from the literature. We find that radio galaxies always have "core"-type profiles, i.e. a shallow profile in the inner part of the galaxy, while radio-quiescent ellipticals may either have "core"-type or "power-law" type profiles. Description: Nuker-model parameters are given for three sets of galaxies. The parameters were derived from Nuker-law fits of the inner parts of the brightness profiles. All observational data are based on HST images. We present the data for 1) the subset of B2 radio galaxies with central dust and 2) without central dust (see Capetti et al., 2000A&A...362..871C), and 3) 3C (FR II type) radio galaxies with images available in the HST archive. We also give general information, including new data on radio power, on two comparison samples: nearby early type galaxies discussed by Faber et al. (1997AJ.....114.1771F) and brightest cluster galaxies that were analysed by Laine et al. (2003AJ.....125..478L). File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1.dat 102 17 Nuker law parameters of B2 radio galaxies with central dust table2.dat 102 22 Nuker law parameters of B2 radio galaxies without central dust table3.dat 102 9 Nuker law parameters of 3CR radio galaxies of FR type II table4.dat 46 33 Faber et al. (1997AJ.....114.1771F) and Laine et al. (2003AJ.....125..478L) basic data
Byte-by-byte Description of file: table1.dat table2.dat table3.dat
Bytes Format Units Label Explanations
1- 10 A10 --- Name Name of radio source 12- 15 F4.2 --- alpha Nuker parameter α (1) 17- 20 F4.2 --- e_alpha 1-{sigme} uncertainty of alpha 22- 25 F4.2 --- beta Nuker parameter β (1) 27- 30 F4.2 --- e_beta 1-{sigme} uncertainty of beta 32- 36 F5.2 --- gamma Nuker parameter γ (1) 38- 41 F4.2 --- e_gamma 1-{sigme} uncertainty of gamma 43- 47 F5.3 arcsec rb Nuker parameter rb (1) 49- 53 F5.3 arcsec e_rb 1-{sigme} uncertainty of rb 55- 59 F5.2 mag/arcsec2 mub Nuker parameter µb (1) 61- 64 F4.2 mag/arcsec2 e_mub 1-{sigme} uncertainty of mub 66- 71 F6.4 --- z Redshift 73- 77 F5.2 [W/Hz] log(Pt) logarithm of total radio power (at 1.4GHz) 79- 84 F6.2 mag VMAG Absolute V magnitude of galaxy 86- 89 F4.1 % b4 ?=- Deviation from pure ellipse in % 91- 93 F3.1 % e_b4 ?=- 1-{sigme} uncertainty of b4 in % 95-102 A8 --- OName Alternative NGC or 3C name
Note (1): The "Nuker profile" is an empirical law introduced by Lauer et al. (1995AJ....110.2622L). In terms of magnitudes the Nuker law reads: µ(r) = µb - [(β-γ)/α]*2.5log2 + 2.5*γ*log(r/rb) + 2.5*[(β-γ)/α]*log(1+(r/rb)α)
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 9 A9 --- Galaxy Name of galaxy (1) 11- 16 F6.4 --- z redshift 18- 23 F6.2 mag VMAG Absolute magnitude of galaxy 25 A1 --- l_log(Pt) Upper limit flag (<) of radio power (2) 26- 30 F5.2 [W/Hz] log(Pt) ?=- logarithm of total radio power (at 1.4GHz) 32 A1 --- Sample F: Faber+ (1997); L: Laine+ (2003) (1) 34- 46 A13 --- Info Information on radio source (3)
Note (1): Galaxy names taken from the original papers by Faber et al. (1997AJ.....114.1771F) and Laine et al. (2003AJ.....125..478L). Note (2): 3-{sigme} detection limit is 1.35mJy (NVSS). Note (3): Some objects could not be searched for radio emission (e.g. because too far to the south for NVSS, or because a precise position is lacking). Galaxies with VMAG>-17 were excluded from the analysis. Abell 168 was excluded because of a large discrepancy between the fit parameter γ and the slope directly measured at 0.05 arcsec.
Acknowledgements: Hans de Ruiter, deruiter(at) History: * 22-Sep-2005: Original table * 27-Oct-2005: in table 2, 2nd row, B2 0120+33 corrected into B2 0120+32
(End) Hans de Ruiter [INAF-OAB, Bologna], Patricia Vannier [CDS] 22-Sep-2005
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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