3 A list of dwarf galaxy candidates in the equatorial zone

The last step of the work has been accomplished on the J, F glass copies of the SERC Equatorial survey belonging to STScI. Altogether 216 both "blue" and "red" $6 \times 6$ degree plates have been inspected in the declination zones -5, -10, and $-15\hbox{$^\circ$ }$ along with 5 equatorial POSS-II fields absent in our previous inspection. Similar to previous work, we selected dwarf galaxy candidates with angular diameters $\geq\hbox{$.\mkern-4mu^\prime$ }5$ by their low or very low surface brightness. Some of the high surface brightness objects were also taken into account.

 

Table 2: Other candidates selected with the same criterion and rejected due to their velocities

No	RA (1950.0) Dec.	$a\times b$		T	SB	NED Ident.	$B_{\rm T}$	$V_{\rm h}$	Notes
51	$02^{\rm h}31^{\rm m}28\hbox{$.\!\!^{\rm s}$ }0$ - $06\hbox{$^\circ$ }34\hbox{$^\prime$ }44\hbox{$^{\prime\prime}$ }$	$0\hbox{$.\mkern-4mu^\prime$ }8$	$0\hbox{$.\mkern-4mu^\prime$ }4$	Ir	L	P09774	--	1407	knot
52	02 46 50.9 - 02 51 43	0.9	0.5	Ir?	L	UGC A44	--	1094
53	04 06 39.3 - 08 45 28	1.0	0.6	Ir	L	P14562	--	894
54	05 39 36.7 - 12 35 09	1.0	0.4	Sm	L	P17621	--	2245
55	05 47 55.8 - 10 18 45	2.0	0.9	SB?	L	P17965	--	895
56	05 49 44.0 - 11 09 05	0.9	0.8	Ir?	L	P18027	15.5	903	pair w.#55
57	08 41 04.4 - 17 12 15	1.8	0.5	Ir	L	P24494	--	2019	knots
58	10 50 29.1 + 02 45 33	1.5	0.5	Ir	L	L135768	17.4	1054
59	11 10 13.9 - 00 17 39	0.5	0.4	Ir	L	ISI, 96	17.8	8472	patchy, blue
60	12 20 35.1 - 13 40 05	1.4	0.9	Ir	L	UGC A278	--	1155	knots
61	12 42 18.7 - 08 51 15	4.0	1.8	Sm	L	UGC A295	--	1378
62	12 56 29.6 - 11 57 31	1.2	0.8	Ir	L	UGC A312	--	1307
63	13 23 43.5 + 02 43 06	0.8	0.4	Ir	L	ISI, 96	16.8	1137	blue
64	13 25 39.4 + 02 32 20	0.8	0.45	Ir	L	ISI, 96	16.3	1221	$\sigma_v=275$
65	14 11 47.0 - 02 47 59	0.8	0.25	Ir	L	ISI, 96	15.8	1853	$\sigma_v=275$
66	14 31 20.7 + 01 42 14	1.0	0.2	Ir	L	ISI, 96	17.4	1829
67	20 06 41.4 - 06 26 05	2.2	1.4	S	L	UGC A417	--	1425
ISI, 96 = Impey et al. (1996).

After exclusion of emulsion defects, isolated Galactic cirrus, and probable distant "normal" LSB galaxies we have compiled the main list of 50 objects. This list is given in Table 1. The table columns contain:

(1)

the running number;

(2)

equatorial coordinates (epoch 1950.0);

(3)

major and minor diameters measured visually on blue plates;

(4)

the morphological type in usual designations ("d" for "dwarf" is omitted);

(5)

a rough estimate of surface brightness (=SB): H - high (equal or brighter than the SB of a normal spiral galaxy, 22 - 23 mag arcsec^-2), L - low (23 - 24 mag arcsec^-2), VL - very low (24 - 25 mag arcsec^-2), EL - extremely low (25 -26 mag arcsec^-2);

(6)

galaxy name in other catalogues and lists as given in the NASA Extragalactic Database (=NED);

(7)

comments concerning morphology, galaxy membership, etc.

Note, that the object #1 (Cetus) was found by us independently from Whiting et al. (1999). In this paper, which was devoted to the discovery and detailed investigation of the Cetus LG galaxy, the authors reported the finding of 75 new VLSB dwarfs in a sky region at $D < 3\hbox{$^\circ$ }$ covered by the ESO/SERC and SERC EJ surveys. Unfortunately, we were unable to compare our list of objects with their unpublished list.

Figures 1-5 displays $5\hbox {$^\prime $ }\times 5\hbox {$^\prime $ }$ images of 50 dwarf galaxy candidates taken from the Digital Sky Survey.

In Table 2 we give for comparison a list of other 17 LSB objects, which were isolated using the same criterion but exhibited radial velocities in excess of 500 km s^-1. The table columns provide the same quantities as in Table 1. We added only two columns, with total magnitude, $B_{\rm t}$, and heliocentric radial velocity, $V_{\rm h}$, from NED. According to the NED data, all objects in Table 2 were catalogued earlier, and their radial velocities together with their angular extent and low surface brightness confirm that these are dwarf galaxies.