The KUG survey has begun 1984 as a project of selecting ultraviolet(UV)-excess galaxies and compiling a catalog, with the Kiso 105-cm Schmidt telescope, by B. Takase and N. Miyauchi-Isobe. Its first series has been compiled into a catalog (by CDS, VII/179A) listing 8104 objects in about 5100 square degrees (Takase & Miyauchi-Isobe 1993).
It was succeeded by its second series project, by N. Miyauchi-Isobe and H. Maehara, and the second one has already selected 1642 objects in about 300 square degrees (Miyauchi-Isobe & Maehara 2003).
In the course of follow-up observations of KUGs (e.g., Maehara et al. 1987, Tomita et al. 1997), it is clarified that the majority of them are spiral or irregular galaxies with intense star formation in their nuclei, bars, disks, or outer regions. These samples give us clues to the understanding of triggering mechanism of star formation, and of the evolution of some types of galaxies. In addition, Seyferts, LINERs, and active galaxies with some peculiarities are included as minor groups of KUGs, being a fainter extension of Markarian galaxies.
The whole surveyed areas and selected objects are shown in Figure 1 (Right map - northern hemisphere, its left end - 0h of right ascension, and its top - 6h).
The KUGs are detected on the ultraviolet(U) and red(R) double exposed 103a-E plates, as bluer galaxies than A-type stars, by eye-inspection. The catalog contains the positions, the brightness, and the morphological types which are eye-estimated in the Palomar Sky Survey Print (PSS).
The second survey will continue until finishing 14 areas already taken on the Schmidt plates.
Recently the SDSS Data Release 1 (DR1) has been published (Abazajian et al. 2003). It contains a catalog of galaxies in which the objects were determined by a software pipeline (Lupton et al. 2001). It seems worth comparing these results, one is determined by eye-inspection and the other by software algorithm.
Figure 2 shows the KUG objects (red dots), and SDSS DR1 galaxies (blue dots) which are sampled in accordance with the magnitude and color ranges of KUGs.
A sample figure of overlapping areas is shown in Figure 3. The area is A0225 of Kiso division system, whose right ascension and declination limits are shown below. Red squares denote KUG objects, and blue dots SDSS galaxies.
In plotting the figure, we first select SDSS's data of galaxies whose positions coincide with those of KUGs, and then examine their magnitude and color (i.e. and ) ranges statistically.
Taking account of these ranges, we select the SDSS galaxies from
the database by
sqlcl.py script. Adopted SQL instructions
are as follows:
SELECT ra, dec, u, g, r, i, z FROM Galaxy WHERE (g>11.3) and (g<17.5) and (g-r>0.2) and (g-r<0.9) and (u-g>0.5) and (u-g<2.0) and (ra>128.9) and (ra<137.5) and (dec>47.1) and (dec<52.7)
As seen in Figure 3, there are lots of SDSS galaxies not identified as KUG objects. Inspecting these unidentified objects on our Schmidt plates and on DSS-II database, we will be able to investigate the characteristics of algorithm used in SDSS galaxy selection, from the eye-inspecting points of view.
The authors express their hearty thanks to all the staffs of Kiso Observatory for their devoted services to every observation and measurement.
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Lupton R. et al. 2001, in ASP Conf. Ser., Vol. 238, Astronomical Data Analysis Software and Systems X, ed. F. R. Harnden, Jr., Francis A. Primini, & Harry E. Payne (San Francisco: ASP), 269
Maehara, H. et al. 1987, PASJ, 39, 393
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