MEASUREMENTS OF ANISOTROPY IN THE COSMIC MICROWAVE BACKGROUND-RADIATION AT 0-DEGREES.5 SCALES NEAR THE STARS HR-5127 AND PHI-HERCULIS

We present measurements of cosmic microwave background (CMB) anisotrop y near the stars HR 5127 and phi Herculis from the fifth flight of the Millimeter-wave Anisotropy eXperiment (MAX). We scanned 8 degrees str ips of the sky with an approximately Gaussian 0.5 degrees FWHM beam an d a 1.4 degrees peak to peak sinusoidal chop. The instrument has four frequency bands centered at 3.5, 6, 9, and 14 cm(-1). The IRAS 100 mu m map predicts that these two regions have low interstellar dust contr ast. The HR 5127 data are consistent with CMB anisotropy. The phi Herc ulis data, which were measured at lower flight altitudes, show time va riability at 9 and 14 cm(-1), which we believe to be due to atmospheri c emission. However, the phi Herculis data at 3.5 and 6 cm-l are essen tially independent of this atmospheric contribution and are consistent with CMB anisotropy. Confusion from Galactic foregrounds is unlikely based on the spectrum and amplitude of the structure at these frequenc ies. If the observed HR 5127 structure and the atmosphere-independent phi Herculis structure are attributed to CMB anisotropy, then we find Delta T/T = [I(I + 1)C-1/2 pi](1/2) = 1.2(-0.3)(+0.4) x 10(-5) for HR 5127 and 1.9(-0.4)(+0.7) x 10(-5) for phi Herculis in the flat band ap proximation. The upper and lower limits represent a 68% confidence int erval added in quadrature with a 10% calibration uncertainty.