  The almost unexplored frequency window from submillimeter to mid-infrared
(mid-IR) may bring new clues about the particle acceleration and transport
processes and the atmospheric thermal response during solar flares. Because of
its technical complexity and the special atmospheric environment needed,
observations at these frequencies are very sparse. The High Altitude THz Solar
Photometer (HATS) is a full-Sun ground-based telescope designed to observe the
continuum from the submillimeter to the mid-IR. It has a 457-mm spherical
mirror with the sensor in its primary focus. The sensor is a Golay cell with
high sensitivity in a very wide frequency range. The telescope has a polar
mount, and a custom-built data acquisition system based on a 32 ksamples per
second, 24 bits (72 dB dynamic range), 8 channels analog-to-digital board.
Changing only the composition of the low- and band-pass filters in front of the
Golay cell, the telescope can be setup to detect very different frequency
bands; making the instrument very versatile. In this article we describe the
telescope characteristics and its development status. Moreover, we give
estimates of the expected fluxes during flares.
