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Radio Continuum Emission at 1.4 GHz from KISS Emission-Line Galaxies
We have searched the Faint Images of the Radio Sky at Twenty centimeters(FIRST) and the NRAO VLA Sky Survey (NVSS) 1.4 GHz radio surveys forsources that are coincident with emission-line galaxy (ELG) candidatesfrom the KPNO International Spectroscopic Survey (KISS). A total of 207of the 2157 KISS ELGs (~10%) in the first two Hα-selected surveylists were found to possess radio detections in FIRST, NVSS, or both.Follow-up spectra exist for all of the radio detections, allowing us todetermine the activity type (star-forming vs. active nucleus) for theentire sample. We explore the properties of the radio-detected KISSgalaxies in order to gain a better insight into the nature ofradio-emitting galaxies in the local universe (z<0.1). No dwarfgalaxies were detected, despite the large numbers of low-luminositygalaxies present in KISS, suggesting that lower mass, lower luminosityobjects do not possess strong galaxian-scale magnetic fields. Because ofthe selection technique used for KISS, our radio ELGs represent aquasi-volume-limited sample, which allows us to develop a clearerpicture of the radio galaxy population at low redshift. Nearlytwo-thirds of the KISS radio galaxies are starburst or star-forminggalaxies, which is in stark contrast to the results of flux-limitedradio surveys, which are dominated by active galactic nuclei (AGNs) andelliptical galaxies (i.e., classical radio galaxies). While there aremany AGNs among the KISS radio galaxies, there are no objects with largeradio powers in our local volume. We derive a radio luminosity function(RLF) for the KISS ELGs that agrees very well with previous RLFs thatadequately sample the lower luminosity radio population.
| Spectroscopy of KISS Emission-Line Galaxy Candidates. I. MDM Observations
Spectroscopic observations for 351 emission-line galaxy candidates fromthe KPNO International Spectroscopic Survey (KISS) have been obtainedusing the MDM Observatory 2.4 m telescope on Kitt Peak. KISS is anongoing wide-field objective-prism survey for extragalacticemission-line objects, which has cataloged over 2200 emission-linegalaxy (ELG) candidates to date. Spectroscopic follow-up observationsare being carried out to study the characteristics of the surveyobjects. The observational data presented here include redshifts,reddening estimates, line equivalent widths, Hα line fluxes, andemission-line ratios. The galaxies have been classified based on theiremission-line characteristics. The procedure for selecting the ELGcandidates in KISS is found to be very reliable: 95% of the candidatesin this sample are verified to have emission lines. A comparison ofobjective-prism survey data-redshifts, Hα line fluxes, andequivalent widths-with the long-slit measurements shows good overallagreement.
| The KPNO International Spectroscopic Survey. II. Hα-selected Survey List 1
The KPNO International Spectroscopic Survey (KISS) is a newobjective-prism survey for extragalactic emission-line objects. Itcombines many of the features of previous slitless spectroscopic surveyswith the advantages of modern CCD detectors and is the first purelydigital objective-prism survey for emission-line galaxies. Here wepresent the first list of emission-line galaxy candidates selected fromour red spectral data, which cover the spectral range 6400 to 7200Å. In most cases, the detected emission line is Hα. Thecurrent survey list covers a 1°-wide strip located atδ=29°30' (B1950.0) and spanning the right ascension range12h15m to 17h0m. An area of62.2 deg2 is covered. A total of 1128 candidate emission-lineobjects have been selected for inclusion in the survey list (18.1deg-2). We tabulate accurate coordinates and photometry foreach source, as well as estimates of the redshift and emission-line fluxand equivalent width based on measurements of the digitalobjective-prism spectra. The properties of the KISS emission-linegalaxies are examined using the available observational data.
| The QDOT all-sky IRAS galaxy redshift survey
We describe the construction of the QDOT survey, which is publiclyavailable from an anonymous FTP account. The catalogue consists ofinfrared properties and redshifts of an all-sky sample of 2387 IRASgalaxies brighter than the IRAS PSC 60-μm completeness limit(S_60>0.6Jy), sparsely sampled at a rate of one-in-six. At |b|>10deg, after removing a small number of Galactic sources, the redshiftcompleteness is better than 98per cent (2086/2127). New redshifts for1401 IRAS sources were obtained to complete the catalogue; themeasurement and reduction of these are described, and the new redshiftstabulated here. We also tabulate all sources at |b|>10 deg with noredshift so far, and sources with conflicting alternative redshiftseither from our own work, or from published velocities. A list of 95ultraluminous galaxies (i.e. with L_60μm>10^12 L_solar) is alsoprovided. Of these, ~20per cent are AGN of some kind; the broad-lineobjects typically show strong Feii emission. Since the publication ofthe first QDOT papers, there have been several hundred velocity changes:some velocities are new, some QDOT velocities have been replaced by moreaccurate values, and some errors have been corrected. We also present anew analysis of the accuracy and linearity of IRAS 60-μm fluxes. Wefind that the flux uncertainties are well described by a combination of0.05-Jy fixed size uncertainty and 8per cent fractional uncertainty.This is not enough to cause the large Malmquist-type errors in the rateof evolution postulated by Fisher et al. We do, however, find marginalevidence for non-linearity in the PSC 60-μm flux scale, in the sensethat faint sources may have fluxes overestimated by about 5per centcompared with bright sources. We update some of the previous scientificanalyses to assess the changes. The main new results are as follows. (1)The luminosity function is very well determined overall but is uncertainby a factor of several at the very highest luminosities(L_60μm>5x10^12L_solar), as this is where the remainingunidentified objects are almost certainly concentrated. (2) Thebest-fitting rate of evolution is somewhat lower than our previousestimate; expressed as pure density evolution with density varying as(1+z)^p, we find p=5.6+/-2.3. Making a rough correction for the possible(but very uncertain) non-linearity of fluxes, we find p=4.5+/-2.3. (3)The dipole amplitude decreases a little, and the implied value of thedensity parameter, assuming that IRAS galaxies trace the mass, isΩ=0.9(+0.45, -0.25). (4) Finally, the estimate of density varianceon large scales changes negligibly, still indicating a significantdiscrepancy from the predictions of simple cold dark matter cosmogonies.
| Redshifts for a sample of fainter galaxies in the first CfA survey slice
Redshifts were measured for 93 of the 94 galaxies in the Zwicky-Nilsonmerged catalog with the value of m(B/01) between 15.5 and 15.7 and withright ascension alpha between 8(h) and 17(h) and declination deltabetween 29 and 30 deg. This region is within the one covered by thefirst slice of the CfA (Center for Astrophysics) survey. The galaxiesreinforce features already visible in the earlier survey.
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