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J/ApJ/409/28     Gravitationally Lensed Quasars (Maoz + 1993)

The Hubble Space Telescope Snapshot Survey. IV A Summary of the Search for Gravitationally Lensed Quasars Maoz D., Bahcall J.N., Schneider D.P., Bahcall N.A., Djorgovski S., Gould A., Kirhakos S., Doxsey R., Meylan G., Yanny B. <Astrophys. J. 409, 28 (1993)> =1993ApJ...409...28M
ADC_Keywords: QSOs ; Gravitational lensing Abstract: The Snapshot Survey was a search for cases of gravitational lensing among intrinsically-luminous, high-redshift quasars using the Hubble Space Telescope (HST) Planetary Camera (PC). The accompanying ASCII tables summarize the results of the survey. Introduction: The Snapshot Survey was a search for cases of gravitational lensing among intrinsically-luminous, high-redshift quasars using the Hubble Space Telescope (HST) Planetary Camera (PC). Bahcall et al. (1992a; hereafter Paper I) described the objectives of the survey, its mode of operation, the sample definition, and the initial results of a small sample. Maoz et al. (1992b, 1993a, 1993b hereafter Papers II, III, and IV) reported results from a progressively larger sample and compared the observed lensing frequency to existing theoretical models. The discovery of a possible sub-arcsecond lens system, the z=3.8 quasar 1208+1011, reported by Maoz et al. (1992a) and Magain et al. (1992), was followed by HST multi-color imaging and spectroscopy as described in Bahcall et al. (1992b) and in Bahcall et al. (1992c), respectively. Star counts based on the Snapshot Survey images are described in Gould, Bahcall, and Maoz (1993). For all objects in the Survey, finding charts and astrometric positions appear in Schneider et al. (1992). The accompanying tables, published in Paper IV, summarize the results of the Snapshot Survey for gravitationally lensed quasars. Table1a.dat combines the results from Papers II, III, and IV into one list ordered by R.A. These tables have more accurately measured quasar magnitudes, and minor corrections have been made in some of the entries listed in the tables in previous papers, so that the present list superseded previous data summaries. Table1b.dat lists the Paper I observations in the same format as table1a.dat. Some of the exposures are only 120s (program 3034) and about half of the initial exposures were through the F785LP filter (similar to I), rather than the F555W filter. We have included in table1b.dat only quasars that were not subsequently re-observed. These files can be merged without repetition. Exposures through the F785LP filter are marked with an "I" in the V_obs column. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1a.dat 81 507 Summary of Full Program Observations table1b.dat 81 52 Summary of Successful Pilot Observations
Byte-by-byte Description of file: table1a.dat table1b.dat
Bytes Format Units Label Explanations
1- 11 A11 --- name *Quasar name, without prefixes (1950 coord.) 12- 19 A8 --- altname Veron name 21- 28 A8 --- date !Date Observed 30- 33 I4 --- HST !HST Program Number 35 A1 --- chip PC chip showing object 36- 44 A9 pix XY *Central coordinate of quasar 46- 49 A4 arcsec off Offset from designated position on chip 6 51- 54 A4 marcsec drift Drift rate (g = guided exposure) 55- 58 A4 mag Vobs Observed V (I indicates F785LP filter) 60- 64 F5.2 mag Vver ?Magnitude tabulated by Veron 66 A1 --- disc *Discovery method 68- 71 F4.2 --- Redsh [1.01/3.8]? Redshift 73- 76 F4.1 mag M ?Absolute magnitude 78- 81 A4 --- note *Notes
Note on name: blank indicates repeated observation of preceding quasar Note on XY: The coordinate of the center of the mosaic (not the chip) is 1, 1 Note on disc: R = radio selected C = selected by color S = Emission lines in spectrum O = Other (e.g. variability) Note on note: An See "Notes on Individual Objects" in Paper n of Snapshot series. B Guided exposure, but quasar offset by $12"$ for unknown reasons. C Quasar image split between PC-6 and PC-7. D Quasar not verified to be in the field of view, but likely present based on brightness and/or expected absence of additional objects (see paper IV). F Possibly some point-spread function asymetry at $0.1-0.2"$ scales. E Quasar just off PC-8. G Identification uncertain. H Quasar image split between PC-7 and PC-8. J Poor fine-lock guiding attempt; multiple/trailed images. K Quasar image split between PC-5 and PC-6. L Cosmic ray event on or near quasar image core.
References: Bahcall, J.N., Maoz, D., Doxsey, R., Schneider, D.P., Bahcall, N.A., Lahav, O. Yanny, B. 1992a, ApJ, 387, 56 (Paper I) Bahcall, J.N., Maoz, D., Schneider, D.P., Yanny, B., and Doxsey, R., 1992b, ApJ, 392, L1 Bahcall, J.N., Hartig, G., Jannuzi, B.T., Maoz, D., & Schneider, D.P. 1992c, ApJL, 400, in press Gould, A., Bahcall, J.N., & Maoz, D. 1992, ApJS, 88, 5 Hunter, D., Faber, S., Light, R., & Shaya, E. 1992, in "WFPC Final Orbital/Science Verification Report", ed. S.M. Faber (Baltimore: STScI) ch. 12 Magain, P., Surdej, J., Vanderriest, C., Pirenne, B., and Hutsemekers, D. 1992, AA, 253, L13 Maoz, D., Bahcall, J.N., Schneider, D.P., Doxsey, R., Bahcall, N.A., Filippenko, A.V., Goss, W.M., Lahav, O. & Yanny, B. 1992a, ApJL, 386, L1 Maoz, D., Bahcall, J.N., Schneider, D.P., Doxsey, R., Bahcall, N.A., Lahav, O. & Yanny, B. 1992b, ApJ, 394, 51 (Paper II) Maoz, D., Bahcall, J.N., Schneider, D.P., Doxsey, R., Bahcall, N.A., Lahav, O. & Yanny, B. 1993, ApJ, 402, 69 (Paper III) Maoz, D., Bahcall, J.N., Schneider, D.P., Bahcall, N.A., Djorgovski, S., Gould, A., Kirhakos, S., Doxsey, R., Meylan, G., & Yanny, B. 1993, ApJ, 409, 28 (Paper IV) Schneider, D.P., et al. 1992, PASP, 104, 678 Veron-Cetty, M.P., & Veron, P. 1987, "A Catalogue of Quasars and Active Nuclei (3rd Edition)" (Munich:ESO) Veron-Cetty, M.P., & Veron, P. 1989, "A Catalogue of Quasars and Active Nuclei (4th Edition)" (Munich:ESO) Veron-Cetty, M.P., & Veron, P. 1991, "A Catalogue of Quasars and Active Nuclei (5th Edition)" (Munich:ESO)
(End) D. Maoz and N.G. Roman [Inst. Adv. Studies, NSSDC/ADC] 4-Aug-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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