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J/A+A/516/A4  NGC1600, NGC4125, NGC7619 extended spectroscopy (Pu+, 2010)

Radially extended kinematics and stellar populations of the massive ellipticals NGC1600, NGC4125 and NGC7619. Constraints on the outer dark halo density profile. Pu S.B., Saglia R.P., Thomas J., Fabricius M., Bender R., Han Z. <Astron. Astrophys. 516, A4 (2010)> =2010A&A...516A...4P
ADC_Keywords: Galaxies, spectra ; Morphology ; Radial velocities ; Velocity dispersion Keywords: galaxies: elliptical and lenticular, cD - Galaxy: abundances - galaxies: kinematic and dynamics - galaxies, individual: NGC1600, NGC4125, NGC7619 Abstract: We present high quality long slit spectra along the major and minor axes out to 1.5-2Re (14-22kpc) of three bright elliptical galaxies (NGC1600, NGC4125, NGC7619) obtained at the Hobby-Eberly Telescope (HET). We derive stellar kinematic profiles and Lick/IDS indices (Hβ, Mgb, Fe_{5015}, Fe_{5270}, Fe_{5335}, Fe_{5406}). Moreover, for NGC4125 we derive gas kinematics and emission line strengths. We model the absorption line strengths using Simple Stellar Populations models that take into account the variation of α/Fe and derive ages, total metallicity and element abundances. Overall, we find that the three galaxies have old and α/Fe overabundant stellar populations with no significant gradients. The metallicity is supersolar at the center with a strong negative radial gradient. For NGC4125, several pieces of evidence point to a recent dissipational merger event. We calculate the broad band color profiles with the help of SSP models. All of the colors show sharp peaks at the center of the galaxies, mainly caused by the metallicity gradients, and agree well with the measured colors. Using the Schwarzschild's axisymmetric orbit superposition technique, we model the stellar kinematics to constrain the dark halos of the galaxies. We use the tight correlation between the Mgb strength and local escape velocity to set limits on their extent by testing different halo sizes. Logarithmic halos cut at 60kpc minimize the overall scatter of the Mgb-Vesc relation. Larger cutoff radii are found if the dark matter density profile is decreasing more steeply at large radii. Description: The stellar kinematics (Table 3) and the Lick absorption line strength indices (Table 6) of NGC1600, NGC4125, NGC7619; the gas kinematics the equivalent widths of Hβ gas emission line, plus the EW ratios [OIII]/Hβ and [NI]/Hβ of NGC4125 (Table 4) presented here have been measured from spectra taken with the Hobby-Eberly Telescope and the Low Resolution Spectrograph. We observed the major and minor axes of these galaxies with a slit width of 3-arcsec, a spectral resolution of sigma∼120km/s and covering the spectral range 4790-5850Å, with seeing values between 1.4 and 2.57-arcsec. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 04 31 39.9 -05 05 10 NGC1600 = NGC 1600 12 08 06.3 +65 10 27 NGC4125 = NGC 4125 23 20 14.7 +08 12 23 NGC7619 = NGC 7619 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 95 351 Stellar kinematics along major and minor axes of NGC1600, NGC4125, NGC7619 table4.dat 79 95 Gas kinematics and emission equivalent width and ratios along major and minor axes of NGC4125 table6.dat 129 352 Lick indices along major and minor axes of NGC1600, NGC4125, NGC7619
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Galaxy Galaxy name 9- 15 F7.2 arcsec R Distance from the galaxy center (G1) 17- 19 I3 deg PA Position angle (G2) 21- 27 F7.2 km/s RV Stellar radial velocity, positive receiding 29- 34 F6.2 km/s e_RV Error on stellar radial velocity 36- 41 F6.2 km/s e:RV Systematic error on stellar radial velocity due to the sky subtraction 44- 49 F6.2 km/s sigma Stellar velocity dispersion 51- 56 F6.2 km/s e_sigma Error on stellar velocity dispersion 58- 63 F6.2 km/s e:sigma Systematic error on stellar velocity dispersion to the sky subtraction 65- 69 F5.2 --- H3 3rd order Hermite coefficient 71- 74 F4.2 --- e_H3 Error on 3rd order Hermite coefficient 76- 79 F4.2 --- e:H3 Systematic error on 3rd order Hermite coefficient to the sky subtraction 81- 85 F5.2 --- H4 4th order Hermite coefficient 87- 90 F4.2 --- e_H4 Error on 4th order Hermite coefficient 92- 95 F4.2 --- e:H4 Systematic error on 4th order Hermite coefficient due to the sky subtraction
Byte-by-byte Description of file: table4.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Galaxy Galaxy name 10- 14 F5.1 arcsec R Distance from the center 16- 18 I3 deg PA Position angle (G2) 20- 25 F6.1 km/s Vgas Gas radial velocity, positive receiding 28- 31 F4.1 km/s e_Vgas Error on gas radial velocity 33- 37 F5.1 km/s sig.gas Gas velocity dispersion 40- 43 F4.1 km/s e_sig.gas Error on gas velocity dispersion 45- 49 F5.2 0.1nm Hbe Equivalent width of the Hβ gas emission 52- 55 F4.2 0.1nm e_Hbe Error on EW of the Hβ gas emission 58- 61 F4.2 --- OH Ratio [OIII]/Hβ of the gas emission EWs 64- 67 F4.2 --- e_OH Error on OH 70- 73 F4.2 --- NH Ratio [NI]/Hβ of the gas emission EWs 76- 79 F4.2 --- e_NH Error on NH
Byte-by-byte Description of file: table6.dat
Bytes Format Units Label Explanations
1- 7 A7 --- Galaxy Galaxy name 9- 15 F7.2 arcsec R Distance from the center (G1) 17- 19 I3 deg PA Position angle (G2) 21- 25 F5.2 0.1nm Hb Hβ line strength 28- 31 F4.2 0.1nm e_Hb Error on the Hβ line strength 33- 37 F5.2 0.1nm e:Hb Systematic error on the Hβ line strength due to the sky subtraction 39- 43 F5.2 0.1nm Mgb Mgb line strength 46- 49 F4.2 0.1nm e_Mgb Error on the Mgb line strength 51- 55 F5.2 0.1nm e:Mgb Systematic error on the Mgb line strength due to the sky subtraction 57- 61 F5.2 0.1nm Fe1 Fe5015 line strength 64- 67 F4.2 0.1nm e_Fe1 Error on the Fe5015 line strength 69- 73 F5.2 0.1nm e:Fe1 Systematic error on the Fe5015 line strength due to the sky subtraction 75- 79 F5.2 0.1nm Fe2 Fe5270 line strength 82- 85 F4.2 0.1nm e_Fe2 Error on the Fe5270 line strength 87- 91 F5.2 0.1nm e:Fe2 Systematic error on the Fe5270 line strength due to the sky subtraction 93- 97 F5.2 0.1nm Fe3 Fe5335 line strength 100-103 F4.2 0.1nm e_Fe3 Error on the Fe5335 line strength 105-109 F5.2 0.1nm e:Fe3 Systematic error on the Fe5335 line strength due to the sky subtraction 111-115 F5.2 0.1nm Fe4 Fe5406 line strength 118-121 F4.2 0.1nm e_Fe4 Error on the Fe5406 line strength 125-129 F5.2 0.1nm e:Fe4 Systematic error on the Fe5406 line strength due to the sky subtraction
Global notes: Note (G1): slit data with R<0" correspond to: * NGC1600: North-East side along the major axis (PA=9) and on the North-West side along the minor axis (PA=99). * NGC4125: South-West side along the major axis (PA=82) and on the South-East side along the minor axis (PA=172). * NGC7619: North-East side along the major axis (PA=36) and on the North-West side along the minor axis (PA=126). Note (G2): Position angles of our galaxies: NGC1600 = [major, minor] are [9, 99] NGC4125 = [major, minor] are [82, 172] NGC7619 = [major, minor] are [36, 126]
Acknowledgements: Pu Shibi, pushibi(at)ynao.ac.cn Roberto Saglia, saglia(at)mpe.mpg.de
(End) Pu Shibi [[YNAO, China], Patricia Vannier [CDS] 19-Apr-2010
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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