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Properties of Molecular Gas in Massive Low Surface Brightness Galaxies, Including New 12CO Observations of Three Malin 1 ``Cousins''
To date, the only low surface brightness (LSB) galaxies that have beendetected in CO are the massive LSB (MLSB) galaxies. In 2003, O'Neil,Schinnerer, & Hofner hypothesized that it is the prominent bulgecomponent in MLSB galaxies, not present in less massive LSB galaxies,that gives rise to the detectable quantities of CO gas. To test thishypothesis, we have used the IRAM 30 m telescope to obtain three new,deep CO J(1-0) and J(2-1) observations of MLSB galaxies. Two of thethree galaxies observed were detected in CO-one in the J(1-0) line andthe other in both the J(1-0) and J(2-1) lines-bringing the total numberof MLSB galaxies with CO detections to five, out of a total of nine MLSBgalaxies observed at CO to date. The third object had no detection to 2mK at CO J(1-0). Comparing all MLSB galaxy CO results with surveys ofhigh surface brightness galaxies, we find that the MLSB galaxies'MH2 and MH2/MHIvalues fall within the ranges typically found for high surfacebrightness objects, albeit at the low end of the distribution, with thetwo MLSB galaxies detected at CO in this survey having the highestMH2/MHI values yet measured for any LSBsystem, by factors of 2-3.
| Kinematics of the local universe. VII. New 21-cm line measurements of 2112 galaxies
This paper presents 2112 new 21-cm neutral hydrogen line measurementscarried out with the meridian transit Nan\c cay radiotelescope. Amongthese data we give also 213 new radial velocities which complement thoselisted in three previous papers of this series. These new measurements,together with the HI data collected in LEDA, put to 6 700 the number ofgalaxies with 21-cm line width, radial velocity, and apparent diameterin the so-called KLUN sample. Figure 5 and Appendices A and B forcorresponding comments are available in electronic form at thehttp://www.edpsciences.com
| Large-Scale Structure at Low Galactic Latitude
We have extended the CfA Redshift Survey to low galactic latitudes toinvestigate the relation between the Great Wall in the North GalacticCap and the Perseus-Pisces chain in the South Galactic Cap. We presentredshifts for 2020 galaxies in the Catalogue of Galaxies and of Clustersof Galaxies (Zwicky et al. 1961-68, CGCG) in the following regions: 4^h^<= α <= 8^h^, 17^h^ <= α <= 20^h^, 0^deg^ <=δ <= 45^deg^. In these regions, the redshift catalogue includes1664 galaxies with B(0) <= 15.5 (of which 820 are newly measured) andis 97% complete. We also include redshifts for an additional 356galaxies in these regions with B(O) > 15.5; of these, 148 werepreviously unmeasured. The CGCG samples the galaxy distribution down tob_II_ = 10^deg^. In this paper, we discuss the acquisition and reductionof the spectra, and we examine the qualitative features of the redshiftdistribution. The Great Wall and the Perseus-Pisces chain are not simplyconnected across the Zone of Avoidance. These structures, which at firstappear to be coherent on scales of ~100 h^-1^ Mpc or more, actually formthe boundaries of neighboring voids of considerably smaller scale,approximately 50h^-1^ Mpc. The structures delineated by ouroptically-selected sample are qualitatively similar to those detected bythe far-infrared-selected IRAS 1.2 Jansky Survey (Fisher et al. 1995).Although the IRAS survey probes more deeply into the Zone of Avoidance,our optically-selected survey provides better sampling of structures atb_II_ >= 10^deg^.
| An image database. II. Catalogue between δ=-30deg and δ=70deg.
A preliminary list of 68.040 galaxies was built from extraction of35.841 digitized images of the Palomar Sky Survey (Paper I). For eachgalaxy, the basic parameters are obtained: coordinates, diameter, axisratio, total magnitude, position angle. On this preliminary list, weapply severe selection rules to get a catalog of 28.000 galaxies, wellidentified and well documented. For each parameter, a comparison is madewith standard measurements. The accuracy of the raw photometricparameters is quite good despite of the simplicity of the method.Without any local correction, the standard error on the total magnitudeis about 0.5 magnitude up to a total magnitude of B_T_=17. Significantsecondary effects are detected concerning the magnitudes: distance toplate center effect and air-mass effect.
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