A limit on the large angular scale polarization of the cosmic microwave background

We present an upper limit on the polarization of the cosmic microwave backg round (CMB) at 7 degrees angular scales in the frequency band between 26 an d 36 GHz, produced by the Polarization Observations of Large Angular Region s experiment. The campaign produced a map of linear polarization over the r ight ascension range 112 degrees -275 degrees at declination 43 degrees. Th e model-independent upper limit on the E-mode polarization component of the CMB at angular scales l=2-20 is 10 muK (95% confidence). The corresponding limit for the B-mode is also 10 muK. Constraining the B-mode power to be z ero, the 95% confidence limit on E-mode power alone is 8 muK.