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J/A+A/404/545       Optical spectrum of M 2-24                 (Zhang+ 2003)

Optical spectrum of the planetary nebula M 2-24. Zhang Y., Liu X.-W. <Astron. Astrophys. 404, 545 (2003)> =2003A&A...404..545Z
ADC_Keywords: Planetary nebulae ; Spectroscopy Keywords: ISM: abundances - planetary nebulae: individual: M 2-24 - ISM: lines and bands Abstract: We have obtained medium-resolution, deep optical long-slit spectra of the bulge planetary nebula (PN) M 2-24. The spectrum covers the wavelength range from 3610-7330Å. Over two hundred emission lines have been detected. The spectra show a variety of optical recombination lines (ORLs) from C, N, O and Ne ions. The diagnostic diagram shows significant density and temperature variations across the nebula. Our analysis suggests that the nebula has a dense central emission core. The nebula was thus studied by dividing it into two regions: 1) an high ionization region characterized by an electron temperature of Te=16300K and a density of logNe(cm-3)=6.3; and 2) a low ionization region represented by Te=11400K and logNe(cm-3)=3.7. A large number of ORLs from C, N, O and Ne ions have been used to determine the abundances of these elements relative to hydrogen. In general, the resultant abundances are found to be higher than the corresponding values deduced from collisionally excited lines (CELs). This bulge PN is found to have large enhancements in two α-elements, magnesium and neon. Description: This is a full list of observed lines of M 2-24 and their measured fluxes. Observations were carried out with the ESO 1.52m telescope using the long-slit spectrograph Boller & Chivens. The spectrum covers the wavelength range from 3610-7330Å. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 18 02 04.1 -34 27 47 M 2-24 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file spectrum.dat 80 207 Observed relative line fluxes, on a scale where Hβ=100
Byte-by-byte Description of file: spectrum.dat
Bytes Format Units Label Explanations
2- 8 F7.2 0.1nm LambdaObs ? The observed wavelength 11- 17 F7.3 --- F(Lambda) ? The observed flux (1) 18 A1 --- u_F(Lambda) [:*] ":" for uncertain value 19 A1 --- f_F(Lambda) [a-z A-L] Blended lines (same letter for lines blended together 21- 27 F7.3 --- I(Lambda) ? The dereddened flux (1) 28 A1 --- n_I(Lambda) [a-z A-L] Blended lines 30- 37 A8 --- Ion The ionic identification 40- 46 F7.2 0.1nm LambdaLab The laboratory wavelength 48- 52 A5 --- Mult The multiplet number 57- 63 A7 --- LowerTerm The lower spectral terms of the transition 66- 73 A8 --- UpperTerm The upper spectral terms of the transition 75- 76 I2 --- g1 The statistical weight of the lower level 78- 79 I2 --- g2 ? The statistical weight of the upper level 80 A1 --- n_g2 [*] *: blended lines, no value in g2
Note (1): All fluxes are normalized such that Hβ=100.
Acknowledgements: Yong Zhang
(End) Y. Zhang [NAO, China] 01-Apr-2003
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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