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J/AJ/106/426          Lick slit spectra of quasar                (Tytler+, 1993)

Lick slit spectra of thirty-eight objective prism quasar candidates and low metallicity halo stars TYTLER D., FAN X.-M., JUNKKARINEN V.T., COHEN R.D. <Astron. J. 106, 426 (1993)> =1993AJ....106..426T (SIMBAD/NED Reference)
ADC_Keywords: QSOs; Spectroscopy; Redshifts Abstract: We present Lick Observatory slit spectra of 38 objects which were claimed to have pronounced ultraviolet excess and emission lines. Zhan & Chen (ZC) selected these objects by eye from a UK Schmidt telescope IIIaJ objective prism plate of a field at 0h 0.0deg (l ~= 98 deg, b ~= -60 deg). We concentrate on m(J) ~= 18-19 objects which Zhan and Chen (ZC) thought were most likely to be quasistellar objects (QSOs) at redshift z(em) ≥ 2.8. Most of our spectra have FWHM spectral resolutions of about 4 A, and relatively high S/N of about 10-50, although some have FWHM ~= 15 A or lower S/N. We find eleven QSOs, four galaxies at z ~= 0.1, twenty-two stars and one unidentified object with a low S/N spectrum. The ZC lists are found to contain many QSOs at low z but few at high z, as expected. Of eleven objects which ZC suggested were QSOs with z(prism) ≤ 2.8, eight (73%) are QSOs. But only three of twenty-five candidates with z(prism) ≥ 2.8 are QSOs, and only two (8%) of these are at z ≥ 2.8. Unfortunately, the ZC prism redshifts are often incorrect: only five of the eleven QSOs are at redshifts similar to z(prism). Six of the QSOs show absorption systems, including Q0000+027A with a relatively strong associated C IV absorption system, and Q0008+008 (V ~= 18.9) with a damped Ly alpha system with an HI column density of 10^21 cm^-2. The stars include a wide variety of spectral types. There is one new DA 4 white dwarf at 170 pc, one sdB at 14 kpc, and three M stars. The rest are of types F, G, and K. We have measured the equivalent widths of the Ca II K line, the G band, and the Balmer lines in ten stars with the best spectra, and we derive metallicities. Seven of them are in the range -2.5 ≤ [Fe/H] ≤ -1.7, while the others are less metal poor. If the stars are dwarfs, then they are at distances of 1 to 7 kpc, but if they are giants, typical distances will be about 10 kpc. References: ZC: Zhan Y. & Chen J-S. 1987, AcApSn 7, 99; Trans. in Chin.A.Ap., 11, 191 ZC: Zhan Y. & Chen J-S. 1987, AcApSn 7, 203; Trans. in Chin.A.Ap., 11, 299 ZC: Zhan Y. & Chen J-S. 1989, AcApSn 9, 37; Trans. in Chin.A.Ap., 13, 139 ZC: Zhan Y. & Chen J-S. 1989, AcApSn 9, 147; Trans. in Chin.A.Ap., 13, 321 File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file notes 80 172 Notes on individual objects table1 67 40 Journal of observations table2 104 38 Summary of spectra table3 74 40 Magnitudes and spectral indices table5 108 52 Emission lines table6 53 39 Major absorption lines in the QSO spectra tables.tex 126 532 TeX version of the tables
Byte-by-byte Description of file: table1
Bytes Format Units Label Explanations
1- 10 A10 --- Name Object designation 14- 22 A9 "DD/MM/YY" Obs Observation date, U.T. 24- 27 I4 s Int.time Integration time 30 A1 --- Setup [ABC] Instrumental setup (see note (1)) 33- 36 I4 0.1nm lamMin []? Minimum wavelength of the total range (for setup A and B) 38- 41 I4 0.1nm lamMax []? Maximun wavelength of the total range (for setup A and B) 43- 46 I4 0.1nm lambMin []? Minimum wavelength of the blue range (for setup C) 48- 51 I4 0.1nm lambMax []? Maximun wavelength of the blue range (for setup C) 54- 57 I4 0.1nm lamrMin []? Minimum wavelength of the red range (for setup C) 59- 62 I4 0.1nm lamrMax []? Maximun wavelength of the red range (for setup C) 65- 67 A3 --- Ref Zhan and Chen references (2) -------------------------------------------------------------------------------- Note (1) Setup A: 10 object with z ≃ 3, observed with the UV Schmidt camera Setup B: 11 intermediate z objects with close neighbours, observed with the UV Schmidt camera Setup C: 19 high z objects, observed with the Kast double spectrograph Note (2) ZC1: Zhan Y. & Chen J-S. 1987, AcApSn 7, 99; Trans. in Chin.A.Ap., 11, 191 ZC2: Zhan Y. & Chen J-S. 1987, AcApSn 7, 203; Trans. in Chin.A.Ap., 11, 299 ZC3: Zhan Y. & Chen J-S. 1989, AcApSn 9, 37; Trans. in Chin.A.Ap., 13, 139 ZC4: Zhan Y. & Chen J-S. 1989, AcApSn 9, 147; Trans. in Chin.A.Ap., 13, 321
Byte-by-byte Description of file: table2
Bytes Format Units Label Explanations
1- 10 A10 --- Name Object designation 12- 15 F4.2 --- zOP []? Objective prism redshift from the ZC references (see table1) 18 I1 --- q_zOP Reliability index Q from the ZC references (see note(1)) 21- 23 A3 --- Type Object type (see note (2)) 25- 27 A3 --- Sp1 Spectral type from the spectral features 29- 33 A5 --- Sp2 Spectral type from (B-V)0 34- 40 F7.4 --- z []? Redshift 41 A1 --- u_z [? ] Uncertainty flag on z 43-104 A62 --- lines Spectral lines -------------------------------------------------------------------------------- Note (1) The reliability index Q = Q1 + Q2, where Q1 is the given value 1, 2, or 3 according to increasing strength of the emission lines, and Q2 is similarly valued according to increasing strength of UV excess. Thus, Q = 6 would label the most reliable candidate Note (2) QSO = quasar gal = galaxy sta = star WD = white dwarf
Byte-by-byte Description of file: table3
Bytes Format Units Label Explanations
1- 10 A10 --- Name Object designation 11 A1 --- Setup [AB] Note flag: 'A' for magnitudes measured from Setup A spectrum, and likely to be systematically too faint; 'B' for magnitudes measured from Setup B spectrum. 14- 17 F4.1 mag B(J) B(J) magnitude from ZC references, obtained from image sizes on a direct Schmidt plate. 20- 24 F5.2 mag U []? U magnitude. U is highly uncertain 27- 31 F5.2 mag B B magnitude. B is highly uncertain 34- 38 F5.2 mag V V magnitude. V is highly uncertain 41- 44 F4.2 mag (B-V)0 (B-V)0 color. (B-V)0 is highly uncertain 47- 50 F4.2 mag (B-V) []? (B-V) color estimated from the Balmer line index HP using: (B-V)0 = 0.962 - 0.292HP + 0.036HP^2 52- 56 F5.2 mag Delta []? Slit (B-V) minus HP index (B-V) 59- 62 F4.2 0.1nm HP []? Balmer line index HP, where HP = -0.120 + 0.5Halpha + 0.555Hgamma, which is the average of the measured equivalent width of Halpha, and an estimate of that width based on the measured equivalent width of Hgamma. 64- 68 F5.2 0.1nm KP []? Index KP', the Ca II K equivalent width measured in the 18 A interval, corrected for interstellar Ca II K absorption by subtracting 0.22 A. 71- 74 F4.2 0.1nm GP []? G-band (CH) index, GP, the equivalent width in the 15 A band around 4300 A.
Byte-by-byte Description of file: table5
Bytes Format Units Label Explanations
1- 10 A10 --- Name Object designation 12- 17 F6.4 --- <z(em)> []? Mean emission redshift 20- 32 A13 --- Ion Ion 35- 41 F7.2 0.1nm lamLab Laboratory vacuum wavelength 42 A1 --- u_lamLab Uncertainty flag on lamLab 44- 49 F6.1 0.1nm lamObs Observed wavelength 52- 56 F5.1 0.1nm EWobs Observed frame equivalent width. All values have a decimal point, so that they will be read correctly by a computer program, but some of the values were originally integers 58- 63 F6.4 --- z(em) Emission redshift 64- 88 A25 --- Com Comments. The comment 'see notes' refers to file notes
Byte-by-byte Description of file: table6
Bytes Format Units Label Explanations
1- 10 A10 --- Name Object designation 13- 14 I2 --- No Sequential number counting the line for this object 17- 22 F6.1 0.1nm WObs []? Observed vacuum wavelength 23 A1 --- n_WObs [d] When 'd', it means that the line was seen by reference ZC2 (see table1 description) 25- 28 F4.1 0.1nm EWobs []? Observed equivalent width 31- 36 A6 --- Ident Line identification 38- 41 I4 0.1nm WLab []? Laboratory wavelength 44- 45 A2 --- n_WLab [bc ] Note flags: 'b' Blended with C IV (1550 A) 'c' see notes file 48- 52 F5.3 --- z(abs) []? Absorption redshift
Origin: AAS CD-ROM series, Volume 1, 1993
(End) Patricia Bauer [CDS] 25-Jul-1994
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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