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3 The data

Our search list was an early version of the list of KK98 containing a few additional galaxies which did not make it into the final version because of their morphology and/or size (i.e. they were too small). Particularly, we took into account the results of HI searches for nearby dwarf galaxies made by Kraan-Korteweg et al. (1994), Huchtmeier et al. (1995), Burton et al. (1996), Huchtmeier & van Driel (1996), Huchtmeier et al. (1997) and Cote et al. (1997). The optical data of our galaxies are given in Table1. The kk-number (or other identification if there is no kk-number) is given in Col. 1, R.A. and Dec. (1950) follow in Cols. 2 and 3. The optical diameters a and b in the de Vaucouleurs (D25) system follow in Cols. 4 and 5, the morphological type in Col. 6 where we use the following coding:
Im - irregular blue object with bright knot(s);
Ir - irregular without knots or with amorphous condensations, the colour is neutral or bluish;
Sm - disturbed spiral or irregular with signs of spiral structure;
Sph - spheroidal, with very low brightness gradient or without any, the color is neutral or redish.

The optical surface brightness (SB) has been coded (see KK98): high (H), low (L), very low (VL), and extremely low (EL) in Col. 7. The total blue magnitude $B_{\rm t}$ and its reference follow in Cols. 8 and 9. "NED'' - data are from the NASA/Extragalactic Database, "IK'' - visual estimates from POSS (typical error is about 0.4 mag) by I. Karachentsev, "6 m'' - accurate photometric data from the 6-m telescope CCD-frames obtained by Karachentsev and coworkers (unpublished); "UH'' - photometric data from U. Hopp (Calar Alto) unpublished. The Galactic extinction follows in Col. 10. Other names (identifications) are listed in Col. 11.

Results of the HI observations are summarized in Table 2. The kk-number is given in Col. 1, the HI-flux [Jykms-1] follows in Col. 2, the maximum emission and/or the rms noise [mJy] in Col. 3, the heliocentric radial velocity plus error in Col. 4, the line widths at the 50%, the 25%, and the 20% level of the peak emission in Col. 5. Distances (Col. 6) have been derived with different methods, there are photometric distances in some cases, in other cases the group membership yields a distance. If no other distance estimate is available, we assumed a Hubble constant of 75 kms-1 Mpc-1 to derive a "kinematic'' distance. The absolute magnitude is given in Col. 7, the integrated HI mass (Col. 8) was calculated as (e.g. Roberts 1969)

\begin{displaymath}(M_{\rm HI}/M_{\hbox{$\odot$ }})= 2.355 \ 10^{5} \times D^{2} \times \int
S_{v}{\rm d}v \end{displaymath}

where D is the distance of the galaxy in Mpc and $\int S_{v}{\rm d}v$ is the integrated HI flux in Jykms-1. The relative HI content $M_{\rm HI}/L_{B}$ follows in Col. 9. Finally, Col. 10 contains comments relative to the telescope used for the observation: unless otherwise noted observations have been performed with the 100-m radiotelescope at Effelsberg, N - marks the Nançay radio telescope, ATCA - the Australia Telescope Compact Array at Culgoora, NSW.

In a number of cases emission at negative radial velocities has been observed (kk 20, kk 236, kk 237; only kk 236 has been plotted as an example). The Dwingeloo HI survey (Hartmann & Burton 1997) has been consulted: in all cases of negative radial velocities extended HI emission was found suggesting that we observed high velocity clouds in our Galaxy.

  \begin{figure}\psfig{,width=6cm}\end{figure} Figure 4: The histogram shows the number of galaxies per velocity interval of 200 kms-1. The distribution of corrected radial velocities (v0) of our galaxy sample demonstrates the local character of these galaxies

  \begin{figure}\psfig{,width=6cm}\end{figure} Figure 5: The distribution of the optical linear diameter A0 in kpc for the whole sample in the de Vaucouleurs (D25) system is given here. Galaxies within 10 Mpc (i.e. within the Local Volume) are shown by shaded areas. The medium value for the shaded areas is $1.4 \pm 0.2$ kpc

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