CONSTRAINTS ON THE HIGH-ℓ POWER SPECTRUM OF MILLIMETER-WAVE ANISOTROPIES FROM APEX-SZ

We present measurements of the angular power spectrum of millimeter wave with the APEX-SZ instrument. APEX-SZ has mapped 0.8 square degrees sky at a frequency of 150 GHz with an angular resolution of 1'. These new significantly improve the constraints on anisotropy power at 150 over the range of angular multipoles 3000 < l < 10,000, limiting the total signal in a flat band power to be less than 105 microK^2 at 95%. We expect both submillimeter-bright, dusty galaxies and to a lesser extent CMB anisotropies from the Sunyaev-Zel'dovich effect (SZE) to contribute to the observed power. Subtracting the SZE power expected for sigma_8=0.8 and masking bright sources, the best fit for the remaining power is C_l = 1.1+0.9-0.8 x 10⁻⁵ micro K^2(1.7+1.4-1.3 Jy^2 sr⁻¹). This agrees well with model predictions for due to submillimeter-bright, dusty galaxies. Comparing this power to the detected by BLAST at 600 GHz, we find the frequency dependence of the fluxes to be S_nu ~ nu^{2.6+0.4-0.2} if both experiments measure same population of sources. Simultaneously fitting for the amplitude of the power spectrum and a Poisson distributed point source population, we place upper limit on the matter fluctuation amplitude of sigma_8 < 1.18 at 95%.