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We present scaling relations between the integrated Sunyaev-Zeldovich Effect (SZE) signal, $Y_{rm SZ}$, its X-ray analogue, $Y_{rm X}equiv M_{rm gas}T_{rm X}$, and total mass, $M_{rm tot}$, for the 45 galaxy clusters in the Bolocam X-ray-SZ (BOXSZ) s ample. All parameters are integrated within $r_{2500}$. $Y_{2500}$ values are measured using SZE data collected with Bolocam, operating at 140 GHz at the Caltech Submillimeter Observatory (CSO). The temperature, $T_{rm X}$, and mass, $M_{rm gas,2500}$, of the intracluster medium are determined using X-ray data collected with Chandra, and $M_{rm tot}$ is derived from $M_{rm gas}$ assuming a constant gas mass fraction. Our analysis accounts for several potential sources of bias, including: selection effects, contamination from radio point sources, and the loss of SZE signal due to noise filtering and beam-smoothing effects. We measure the $Y_{2500}$--$Y_{rm X}$ scaling to have a power-law index of $0.84pm0.07$, and a fractional intrinsic scatter in $Y_{2500}$ of $(21pm7)%$ at fixed $Y_{rm X}$, both of which are consistent with previous analyses. We also measure the scaling between $Y_{2500}$ and $M_{2500}$, finding a power-law index of $1.06pm0.12$ and a fractional intrinsic scatter in $Y_{2500}$ at fixed mass of $(25pm9)%$. While recent SZE scaling relations using X-ray mass proxies have found power-law indices consistent with the self-similar prediction of 5/3, our measurement stands apart by differing from the self-similar prediction by approximately 5$sigma$. Given the good agreement between the measured $Y_{2500}$--$Y_{rm X}$ scalings, much of this discrepancy appears to be caused by differences in the calibration of the X-ray mass proxies adopted for each particular analysis.
We report measurements of the fluctuations in atmospheric emission (atmospheric noise) above Mauna Kea recorded with Bolocam at 143 and 268 GHz from the Caltech Submillimeter Observatory (CSO). The 143 GHz data were collected during a 40 night observ ing run in late 2003, and the 268 GHz observations were made in early 2004 and early 2005 over a total of 60 nights. Below 0.5 Hz, the data time-streams are dominated by atmospheric noise in all observing conditions. The atmospheric noise data are consistent with a Kolmogorov-Taylor (K-T) turbulence model for a thin wind-driven screen, and the median amplitude of the fluctuations is 280 mK^2 rad^(-5/3) at 143 GHz and 4000 mK^2 rad^(-5/3) at 268 GHz. Comparing our results with previous ACBAR data, we find that the normalization of the power spectrum of the atmospheric noise fluctuations is a factor of 80 larger above Mauna Kea than above the South Pole at millimeter wavelengths. Most of this difference is due to the fact that the atmosphere above the South Pole is much drier than the atmosphere above Mauna Kea. However, the atmosphere above the South Pole is slightly more stable as well: the fractional fluctuations in the column depth of precipitable water vapor are a factor of sqrt(2) smaller at the South Pole compared to Mauna Kea. Based on our atmospheric modeling, we developed several algorithms to remove the atmospheric noise, and the best results were achieved when we described the fluctuations using a low-order polynomial in detector position over the 8 arcmin field of view (FOV). However, even with these algorithms, we were not able to reach photon-background-limited instrument photometer (BLIP) performance at frequencies below 0.5 Hz in any observing conditions.
We have surveyed two science fields totaling one square degree with Bolocam at 2.1 mm to search for secondary CMB anisotropies caused by the Sunyaev- Zeldovich effect (SZE). The fields are in the Lynx and Subaru/XMM SDS1 fields. Our survey is sensiti ve to angular scales with an effective angular multipole of l_eff = 5700 with FWHM_l = 2800 and has an angular resolution of 60 arcseconds FWHM. Our data provide no evidence for anisotropy. We are able to constrain the level of total astronomical anisotropy, modeled as a flat bandpower in C_l, with frequentist 68%, 90%, and 95% CL upper limits of 590, 760, and 830 uKCMB^2. We statistically subtract the known contribution from primary CMB anisotropy, including cosmic variance, to obtain constraints on the SZE anisotropy contribution. Now including flux calibration uncertainty, our frequentist 68%, 90% and 95% CL upper limits on a flat bandpower in C_l are 690, 960, and 1000 uKCMB^2. When we instead employ the analytic spectrum suggested by Komatsu and Seljak (2002), and account for the non-Gaussianity of the SZE anisotropy signal, we obtain upper limits on the average amplitude of their spectrum weighted by our transfer function of 790, 1060, and 1080 uKCMB^2. We obtain a 90% CL upper limit on sigma8, which normalizes the power spectrum of density fluctuations, of 1.57. These are the first constraints on anisotropy and sigma8 from survey data at these angular scales at frequencies near 150 GHz.
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