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2 Observations

Observations were performed with three different radio telescopes for different declination ranges. The 100-m radiotelescope at Effelsberg was used for declinations greater than $-31\hbox{$^\circ$ }$, the Nançay radio telescope was selected for galaxies in the declination range $-38\hbox{$^\circ$ }\le
-31\hbox{$^\circ$ }$, and the compact array of the Australia Telescope was used for galaxies south of $-38\hbox{$^\circ$ }$.

2.1 Effelsberg observations

The radio telescope at Effelsberg has been used in the total power mode (ON - OFF) combining a reference field 5 min earlier in R.A. with the on-source position. A dual channel HEMT receiver had a system noise of 30 K.

The 1024 channel autocorrelator was split into 4 bands (bandwidth 6.25 MHz) of 256 channels each shifted in frequency by 5 MHz with respect to their neighbor in order to cover a velocity range from -470 to 3970 kms-1 overlapping 1.5 MHz between channels. The resulting channel separation was 5.1 kms-1 yielding a resolution of 6.2 kms-1 (10.2 kms-1 after Hanning smoothing). The HI profiles observed with the 100-m radiotelescope are presented in Fig. 1 in order of increasing R.A. as in Table1. The half power beam widths (HPBW) of the Effelsberg telescope at this wavelength is 9 $.\mkern -4mu^\prime $3.

2.2 Nançay observations

For 15 galaxies in the declination range $-38\hbox{$^\circ$ }\le
-31\hbox{$^\circ$ }$ the Nançay radio telescope was used with the same velocity resolution and coverage. Major differences to the description given for the Effelsberg observations were a different system noise (45 K), a different antenna beam ( $3\hbox {$.\mkern -4mu^\prime $ }6 \times 22\hbox {$^\prime $ }$ in R.A. and Dec. for this declination range), and shorter integration phases with a cycle of 2 minutes for the ON and the OFF positions. Nine galaxies have been detected (Fig.2).

2.3 Compact Array of the Australia Telescope

40 of the 57 galaxies south of declination $-38\hbox{$^\circ$ }$ have been observed with the Compact Array of the Australia Telescope. For this HI search we have chosen the 750A antenna array configuration in order to yield an antenna beam comparable to the optical size of the smallest galaxies (i.e. $\sim$ 1 $\hbox {$^\prime $ }$). The frequency setup and correlator configuration was such that we obtained a velocity coverage from -450 to +2900 kms-1 and a channel separation of 6.6 kms-1 (i.e. a resolution of 7.9 kms-1). Each galaxy was observed for 10 min every few hours. With five to six observations per target position we achieved a regular coverage of the uv plane for these "snapshot mode'' observations. The resulting integrated HI profiles are given in Fig. 3 (for a more detailed discussion of these data see Huchtmeier et al. in preparation). We may miss some flux with the interferometer (missing flux) as the observed HI emission extends over more than 2 $\hbox {$^\prime $ }$ per channel for over 60% of the galaxies. Galaxies from the kk98 sample not observed are: kk11, kk63, kk179, kk184, kk189, kk190, kk197, kk203, kk211, kk213, kk214, kk217, kk221, kk222, kk235, kk244, kk248.

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