Table A.1: Continuum sources in the 1.4 GHz VLA C and BnA configuration images.
Source Position (B1950.0) S $_{1.4~\rm GHz}$ Source Comments

name $\alpha$ (00 $^{\rm h}$ ) $\delta$ (-25 $^{\circ }$ ) (mJy) size

S1 44 $^{\rm m}$ 32 $.\!\!^{\rm s}$ 65 40 $^{\prime}$ 11 $.\!\!^{\prime\prime}$ 2 3.4 U^a

S2 44 $^{\rm m}$ 35 $.\!\!^{\rm s}$ 95 26 $^{\prime}$ 52 $.\!\!^{\prime\prime}$ 6 10.8 4.0 $^{\prime \prime }$ $\times$ 1.6 $^{\prime \prime }$

S3^b 44 $^{\rm m}$ 44 $.\!\!^{\rm s}$ 57 34 $^{\prime}$ 06 $.\!\!^{\prime\prime}$ 0 19.0 0.5 $^{\prime \prime }$ $\times$ 0.4 $^{\prime \prime }$ B1

S4^b 45 $^{\rm m}$ 17 $.\!\!^{\rm s}$ 56 30 $^{\prime}$ 00 $.\!\!^{\prime\prime}$ 0 25.4 B2; 3 point sources

S5^b 45 $^{\rm m}$ 27 $.\!\!^{\rm s}$ 50 28 $^{\prime}$ 53 $.\!\!^{\prime\prime}$ 0 1.8 U real feature ?

S6 45 $^{\rm m}$ 31 $.\!\!^{\rm s}$ 57 34 $^{\prime}$ 53 $.\!\!^{\prime\prime}$ 7 56 2.4 $^{\prime \prime }$ $\times$ 0.5 $^{\prime \prime }$ B3

S7 45 $^{\rm m}$ 34 $.\!\!^{\rm s}$ 03 43 $^{\prime}$ 59 $.\!\!^{\prime\prime}$ 7 7.2 3 $^{\prime \prime }$ $\times$ 1 $^{\prime \prime }$ ? possibly resolved

S8 45 $^{\rm m}$ 33 $.\!\!^{\rm s}$ 79 32 $^{\prime}$ 49 $.\!\!^{\prime\prime}$ 1 1.6 U

S9 45 $^{\rm m}$ 37 $.\!\!^{\rm s}$ 70 27 $^{\prime}$ 34 $.\!\!^{\prime\prime}$ 9 2.8 U

15^c 45 $^{\rm m}$ 06 $.\!\!^{\rm s}$ 12 31 $^{\prime}$ 55 $.\!\!^{\prime\prime}$ 3 2.0 2 $^{\prime \prime }$ $\times$ 2 $^{\prime \prime }$ possibly resolved

19^c 45 $^{\rm m}$ 12 $.\!\!^{\rm s}$ 07 32 $^{\prime}$ 55 $.\!\!^{\prime\prime}$ 7 1.2 4.5 $^{\prime \prime }$ $\times$ 2.1 $^{\prime \prime }$

20^c 45 $^{\rm m}$ 13 $.\!\!^{\rm s}$ 13 33 $^{\prime}$ 01 $.\!\!^{\prime\prime}$ 1 3.5 4.1 $^{\prime \prime }$ $\times$ 3.4 $^{\prime \prime }$

22^c 45 $^{\rm m}$ 15 $.\!\!^{\rm s}$ 75 32 $^{\prime}$ 01 $.\!\!^{\prime\prime}$ 2 1.5 8.6 $^{\prime \prime }$ $\times$ 5.6 $^{\prime \prime }$ within diffuse em.

23^d 45 $^{\rm m}$ 12 $.\!\!^{\rm s}$ 91 31 $^{\prime}$ 23 $.\!\!^{\prime\prime}$ 9 0.6 - too weak

24^d 45 $^{\rm m}$ 15 $.\!\!^{\rm s}$ 69 31 $^{\prime}$ 51 $.\!\!^{\prime\prime}$ 2 0.9 - too weak

25^d 45 $^{\rm m}$ 16 $.\!\!^{\rm s}$ 80 32 $^{\prime}$ 13 $.\!\!^{\prime\prime}$ 9 0.7 - too weak

^a U - unresolved, even in the BnA configuration images.

^b These are within 2-3 synthesized beams of -ve extended emission in the C configuration image.

^c Sources in U00 (Ulvestad 2000) with inaccurate flux densities, positions.

^d Sources seen in BnA image but not in Ulvestad (2000).

**Table A.1:** Continuum sources in the 1.4 GHz VLA C and BnA configuration images.
Source	Position (B1950.0)	S $_{1.4~\rm GHz}$	Source	Comments
name	$\alpha$ (00 $^{\rm h}$ )	$\delta$ (-25 $^{\circ }$ )	(mJy)	size
S1	44 $^{\rm m}$ 32 $.\!\!^{\rm s}$ 65	40 $^{\prime}$ 11 $.\!\!^{\prime\prime}$ 2	3.4	U^a
S2	44 $^{\rm m}$ 35 $.\!\!^{\rm s}$ 95	26 $^{\prime}$ 52 $.\!\!^{\prime\prime}$ 6	10.8	4.0 $^{\prime \prime }$ $\times$ 1.6 $^{\prime \prime }$
S3^b	44 $^{\rm m}$ 44 $.\!\!^{\rm s}$ 57	34 $^{\prime}$ 06 $.\!\!^{\prime\prime}$ 0	19.0	0.5 $^{\prime \prime }$ $\times$ 0.4 $^{\prime \prime }$	B1
S4^b	45 $^{\rm m}$ 17 $.\!\!^{\rm s}$ 56	30 $^{\prime}$ 00 $.\!\!^{\prime\prime}$ 0	25.4		B2; 3 point sources
S5^b	45 $^{\rm m}$ 27 $.\!\!^{\rm s}$ 50	28 $^{\prime}$ 53 $.\!\!^{\prime\prime}$ 0	1.8	U	real feature ?
S6	45 $^{\rm m}$ 31 $.\!\!^{\rm s}$ 57	34 $^{\prime}$ 53 $.\!\!^{\prime\prime}$ 7	56	2.4 $^{\prime \prime }$ $\times$ 0.5 $^{\prime \prime }$	B3
S7	45 $^{\rm m}$ 34 $.\!\!^{\rm s}$ 03	43 $^{\prime}$ 59 $.\!\!^{\prime\prime}$ 7	7.2	3 $^{\prime \prime }$ $\times$ 1 $^{\prime \prime }$ ?	possibly resolved
S8	45 $^{\rm m}$ 33 $.\!\!^{\rm s}$ 79	32 $^{\prime}$ 49 $.\!\!^{\prime\prime}$ 1	1.6	U
S9	45 $^{\rm m}$ 37 $.\!\!^{\rm s}$ 70	27 $^{\prime}$ 34 $.\!\!^{\prime\prime}$ 9	2.8	U
15^c	45 $^{\rm m}$ 06 $.\!\!^{\rm s}$ 12	31 $^{\prime}$ 55 $.\!\!^{\prime\prime}$ 3	2.0	2 $^{\prime \prime }$ $\times$ 2 $^{\prime \prime }$	possibly resolved
19^c	45 $^{\rm m}$ 12 $.\!\!^{\rm s}$ 07	32 $^{\prime}$ 55 $.\!\!^{\prime\prime}$ 7	1.2	4.5 $^{\prime \prime }$ $\times$ 2.1 $^{\prime \prime }$
20^c	45 $^{\rm m}$ 13 $.\!\!^{\rm s}$ 13	33 $^{\prime}$ 01 $.\!\!^{\prime\prime}$ 1	3.5	4.1 $^{\prime \prime }$ $\times$ 3.4 $^{\prime \prime }$
22^c	45 $^{\rm m}$ 15 $.\!\!^{\rm s}$ 75	32 $^{\prime}$ 01 $.\!\!^{\prime\prime}$ 2	1.5	8.6 $^{\prime \prime }$ $\times$ 5.6 $^{\prime \prime }$	within diffuse em.
23^d	45 $^{\rm m}$ 12 $.\!\!^{\rm s}$ 91	31 $^{\prime}$ 23 $.\!\!^{\prime\prime}$ 9	0.6	-	too weak
24^d	45 $^{\rm m}$ 15 $.\!\!^{\rm s}$ 69	31 $^{\prime}$ 51 $.\!\!^{\prime\prime}$ 2	0.9	-	too weak
25^d	45 $^{\rm m}$ 16 $.\!\!^{\rm s}$ 80	32 $^{\prime}$ 13 $.\!\!^{\prime\prime}$ 9	0.7	-	too weak

Source LaTeX | All tables | In the text

	1 Introduction
	2 Observations
	3 Results
	4 The morphology and analysis of the extended H92 $\alpha$ RRL emission
	5 A multi-density model for the ionised gas in NGC 253
	6 Discussion
	7 Summary and conclusions
	References
	Online Material
	Appendix A: Radio continuum sources in the disk of NGC 253

^a U - unresolved, even in the BnA configuration images.
^b These are within 2-3 synthesized beams of -ve extended emission in the C configuration image.
^c Sources in U00 (Ulvestad 2000) with inaccurate flux densities, positions.
^d Sources seen in BnA image but not in Ulvestad (2000).