  We report on X-ray, optical, infrared and radio observations of the X-ray dim
isolated neutron star (XDINS) 1RXS J214303.7+065419 (also known as RBS 1774).
The X-ray observation was performed with the High Resolution Camera on board of
the Chandra X-ray Observatory, allowing us to derive the most accurate position
for this source (alpha = 21h43m3.38s, delta= +6deg54'17".53; 90% uncertainty of
0."6). Furthermore, we confirmed with a higher spatial accuracy the point-like
nature of this X-ray source. Optical and infrared observations were taken in B,
V, r', i', J, H and Ks filters using the Keck, VLT, Blanco and Magellan
telescopes, while radio observations were obtained from the ATNF Parkes single
dish at 2.9GHz and 708MHz. No plausible optical and/or infrared counterpart for
RBS 1774 was detected within the refined sub-arsecond Chandra X-ray error
circle. Present upper limits to the optical and infrared magnitudes are r'>25.7
and J>22.6 (5 sigma confidence level). Radio observations did not show evidence
for radio pulsations down to a luminosity at 1.4 GHz of L < 0.02 mJy kpc^2, the
deepest limit up to date for any XDINS, and lower than what expected for the
majority of radio pulsars. We can hence conclude that, if RBS 1774 is active as
radio pulsar, its non detection is more probably due to a geometrical bias
rather than to a luminosity bias. Furthermore, no convincing evidence for
RRAT-like radio bursts have been found. Our results on RBS 1774 are discussed
and compared with the known properties of other thermally emitting neutron
stars and of the radio pulsar population.
