  We report the first near infrared (NIR) imaging of a circumstellar annular
disk around the young (~8 Myr), Vega-like star, HR 4796A. NICMOS coronagraph
observations at 1.1 and 1.6 microns reveal a ring-like symmetrical structure
peaking in reflected intensity 1.05 arcsec +/- 0.02 arcsec (~ 70 AU) from the
central A0V star. The ring geometry, with an inclination of 73.1 deg +/- 1.2
deg and a major axis PA of 26.8 deg +/- 0.6 deg, is in good agreement with
recent 12.5 and 20.8 micron observations of a truncated disk (Koerner, et al.
1998). The ring is resolved with a characteristic width of less than 0.26
arcsec (17 AU) and appears abruptly truncated at both the inner and outer
edges. The region of the disk-plane inward of ~60 AU appears to be relatively
free of scattering material. The integrated flux density of the part of the
disk that is visible (greater than 0.65 arcsec from the star) is found to be
7.5 +/- 0.5 mJy and 7.4 +/- 1.2 mJy at 1.1 and 1.6 microns, respectively.
Correcting for the unseen area of the ring yields total flux densities of 12.8
+/- 1.0 mJy and 12.5 +/- 2.0 mJy, respectively (Vega magnitudes = 12.92 /+-
0.08 and 12.35 +/-0.18). The NIR luminosity ratio is evaluated from these
results and ground-based photometry of the star. At these wavelengths
Ldisk(lambda)/L*(lambda) = 1.4 +/- 0.2E-3 and 2.4 +/- 0.5E-3, giving reasonable
agreement between the stellar flux scattered in the NIR and that which is
absorbed in the visible and re-radiated in the thermal infrared. The somewhat
red reflectance of the disk at these wavelengths implies mean particle sizes in
excess of several microns, larger than typical interstellar grains. The
confinement of material to a relatively narrow annular zone implies dynamical
constraints on the disk particles by one or more as yet unseen bodies.
