| abstract |
The invention relates to apparatus maintaining extremely low and constant temperatures. The helium 3 (He 3 ) cryostat is disposed inside a portable helium 4 (He 4 ) cryostat which is constituted by a Dewar jar 2 with helium 4 at 6. The helium 3 cryostat comprises an evaporation chamber 11, a reservoir 13, an adsorption chamber 16 with an adsorbent 17, two pipes 15 and 18 and a valve 20. Particular applications in conjunction with a bolometer, the sensitive element of which is shown at 26. |