2005A&A...434..497T

This paper, the second in a series of papers on the conspicuous compact HII region N88A in the Small Magellanic Cloud, emphasizes the properties of the H₂ emission as well as of the surrounding stellar content of the entire Henize region N88. Using VJK photometry and stellar evolutionary models our analysis of N88 reveals a miscellaneous population of evolved stars of low and intermediate masses (1.2-8M_☉) in an age range of 40Myr to 6Gyr. The majority of these stars are found in the cluster HW 82 which also contains several main sequence stars. A_V in N88A is revisited using near-IR Pδ, Pγ and Pβ Paschen emission lines. Spectroscopic measurements of the H₂ emission in Z, J, H and K bands allow, in conjunction with measurements in the visible, a full spectral coverage from 0.37µm to 2.45µm. Long slit spectroscopy through N88 and the nebulosity to the east clearly distinguishes the ionization zone in N88 characterized by H I and He I emission with pure H₂ emission clearly delineated in the cloud nearby. The principal excitation mechanism for H₂ is through fluorescent excitation in a photodissociation region associated with N88A.