J/ApJ/708/868 CIV candidates (Cooksey+, 2010)
The last eight-billion years of intergalactic C IV evolution.
Cooksey K.L., Thom C., Prochaska J.X., Chen H.-W.
<Astrophys. J., 708, 868-908 (2010)>
=2010ApJ...708..868C 2010ApJ...708..868C
ADC_Keywords: Active gal. nuclei ; QSOs ; Spectra, ultraviolet ; Redshifts ;
Equivalent widths ; Spectroscopy
Keywords: intergalactic medium - quasars: absorption lines -
techniques: spectroscopic
Abstract:
We surveyed the Hubble Space Telescope UV spectra of 49 low-redshift
quasars for z<1 CIV candidates, relying solely on the characteristic
wavelength separation of the doublet. After consideration of the
defining traits of CIV doublets (e.g., consistent line profiles, other
associated transitions, etc.), we defined a sample of 38 definite
(group G=1) and five likely (G=2) doublets with rest equivalent widths
Wr for both lines detected at ≥3σWr. We conducted Monte
Carlo completeness tests to measure the unblocked redshift (Δz)
and co-moving path length (ΔX) over which we were sensitive to
CIV doublets of a range of equivalent widths and column densities.
Using the power-law model of f(N(C+3)), we measured the C+3 mass
density relative to the critical density:
ΩC+3=(6.20+1.82-1.52)x10-8 for 13≤logN(C+3)≤15.
Description:
To assemble our target list, we searched the HST Space Telescope
Imaging Spectrograph (STIS) and Goddard High-Resolution Spectrograph
(GHRS) spectroscopic archives for objects with target descriptions
including the terms, e.g., QSO, quasar, Seyfert, etc. Our final list
included 69 objects with redshifts 0.001<zem<2.8. We retrieved all
available spectra from the Multimission Archive at Space Telescope
(MAST), including supplementary FUSE data, when available
(see Table 1). Ultimately, 49 targets had spectra with usable
wavelength coverage and S/N ratios.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
targets.dat 54 69 List of targets
table1.dat 166 198 Observation summary (69 targets)
table2.dat 96 7816 CIV candidates summary (49 targets)
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See also:
III/157 : An Ultraviolet Atlas of Quasar and Blazar Spectra (Kinney+, 1991)
J/A+A/530/A50 : Principal Component Analysis of QSO UV spectra (Paris+,
2011)
J/MNRAS/401/2715 : CIV column densities in z<2.5 QSOs (D'odorico+, 2010)
J/ApJ/702/767 : CIV and FeKα Baldwin effects in AGNs (Wu+, 2009)
J/ApJ/666/757 : CIV(1549Å emission line in AGNs (Sulentic+, 2007)
J/ApJS/164/1 : IGM absorbers toward HE 0226-4110 (Lehner+, 2006)
J/ApJ/613/129 : Equivalent widths of QSOs (Wise+, 2004)
J/ApJS/155/351 : Absorption toward PG 1116+215 (Sembach+, 2004)
J/ApJS/122/355 : Properties of low z QSO absorption systems (Vanden Berk+,
1999)
J/A+A/294/377 : HS1700+6416 UV absorption (Vogel+, 1995)
J/ApJ/475/469 : Composite HST Spectrum of Quasars (Zheng+ 1997)
http://www.ucolick.org/~xavier/HSTCIV/ : Supplementary data to this paper
Byte-by-byte Description of file: targets.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Target Target name
24- 25 I2 h RAh Hour of Right Ascension (J2000)
27- 28 I2 min RAm Minute of Right Ascension (J2000)
30- 34 F5.2 s RAs Second of Right Ascension (J2000)
36 A1 --- DE- Sign of the Declination (J2000)
37- 38 I2 deg DEd Degree of Declination (J2000)
40- 41 I2 arcmin DEm Arcminute of Declination (J2000)
43- 47 F5.2 arcsec DEs Arcsecond of Declination (J2000)
49- 54 F6.4 --- z Redshift
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 22 A22 --- Target Target name (G1)
24- 25 I2 h RAh Hour of Right Ascension (J2000)
27- 28 I2 min RAm Minute of Right Ascension (J2000)
30- 31 I2 s RAs Second of Right Ascension (J2000)
33 A1 --- DE- Sign of the Declination (J2000)
34- 35 I2 deg DEd Degree of Declination (J2000)
37- 38 I2 arcmin DEm Arcminute of Declination (J2000)
40- 41 I2 arcsec DEs Arcsecond of Declination (J2000)
43- 48 F6.4 --- z Redshift
50- 53 A4 --- Inst Instrument used in the observation
55- 60 A6 --- Grating Grating used in the observation
62- 67 I6 --- R Grating resolution
69- 71 I3 km/s FWHM Grating FWHM
75- 76 A2 --- l_S/N [≤] Limit flag on S/N
78- 80 I3 pix-1 S/N Signal-to-noise from normalized spectrum
82- 85 I4 0.1nm Wmin Minimum wavelength of the observation (1)
87- 90 I4 0.1nm Wmax Maximum wavelength of the observation (1)
92- 94 I3 ks Texp Exposure time
96-147 A52 --- PID Observation(s) identification number
149-166 A18 --- Notes Additional notes(s)
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Note (1): In units of Angstroms.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Target Target name (G1)
19- 23 F5.3 --- z Target redshift
25- 32 F8.5 --- z1548 ? CIV 1548 candidate redshift
34- 39 F6.1 km/s dvabs ? CIV 1550 candidate velocity difference
41- 47 F7.2 0.1nm wvr Transition rest wavelength (1)
49- 55 F7.2 0.1nm wvlo Lower absorption line boundary (1)
57- 63 F7.2 0.1nm wvhi Upper absorption line boundary (1)
66 A1 --- l_EWr The 2σ limit flag on EWr
68- 73 I6 10-13m EWr Rest equivalent width (2)
75- 77 I3 10-13m e_EWr ? The 1σ uncertainty in EWr (2)
79 A1 --- l_logN The 2σ limit flag on logN
81- 85 F5.2 [cm-2] logN Log column density
87 A1 --- f_logN [a] Flag on logN (3)
89- 92 F4.2 [cm-2] e_logN ? The 1σ uncertainty in logN
94- 96 I3 --- Flag [64,511]? Binary flag (4)
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Note (1): In units of Angstroms.
Note (2): In units of milliAngstroms.
Note (3):
a = logN measured by assuming Wr results from the linear portion
of the curve of growth (COG).
Note (4): CIV diagnostic flags described as follows:
256 = Wr,1548≥3σ(Wr,1548)
128 = Wr,1550≥3σ(Wr,1550)
64 = 1-σ(RW)≤RW≤2+σ(RW)
32 = |δνCIV|≤10km/s
16 = Candidate Lyα with Wr,1215≥3σ(Wr,1215)
8 = CIV 1548 outside Lyα forest
4 = CIV 1548 outside H2 forest
2 = ≥68.3% AOD profile per element (pixel) in 1σ agreement
1 = Other candidate absorption lines with Wr≥3σWr_
The flags are binary and sum uniquely. See section 3.2 for further
details.
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Global notes:
Note (G1): HE0226-4410 is assumed to be a misprint for HE 0226-4110;
corrected at CDS.
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History:
* 15-Feb-2012: from electronic version of the journal
+ List of targets positions from http://www.ucolick.org/~xavier/HSTCIV
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 15-Feb-2012