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NGC 2835 SAB(rs)c
CTIO 1.5-m
R. Buta, G. B. Purcell
B-band, 600s, 0.435 arcsec/pix
18.0-28.0
bar torque class: x
de V 63: SB( $\underline{\rm r}$s)c
SB94: SBc(rs)I.2
SGC: SAB(rs)c
CSRG: SAB(rs)c

Description - NGC 2835 is a prototypical late-type spiral with a strong multi-armed spiral pattern. The resolution of the arms is very high, and at least four clear arms are present, one showing branching. Although de Vaucouleurs (1963) and SB94 favored a bar classification of SB, the bar is rather weak in blue light, and on the basis of the high quality CCD image, we favor the classification SAB. NGC 2835 is an especially good example of the mixed ring variety (rs). The ring is only partial on each side, and the galaxy fits neatly into the central part of the RHS.

NGC 2835

Multi-wavelength morphology - The close-up B-image below shows that there is dust in the bar of NGC 2835. However, this dust is not offset to the leading edges, but is a linear feature crossing left of the nucleus. In the B-I color index map, the dust lane is redder than the stars forming the bar. In fact, this map shows that the bar is bluest on its leading edges and is also bluer than the surrounding disk.

Close-up images of NGC 2835 in B (left) and B-I (right).

Interpretations - The deprojected image shows that the inner pseudoring is a relatively circular feature. The ring could be a resonance feature, but the specific resonance is unknown. The likely interpretation is ILR given the late-type nature of the bar. Note how the bar mostly fails to fill the pseudoring, which also indicates the ring is likely to be a resonance.

Deprojected B-band image of NGC 2835



 
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ronald.buta
2001-07-24