2 2009 Fermi Symposium, Washington, D.C., Nov. 2-5 Figure 1: The SMA light curves for 3C 454.3. The open circles represent the 850 µ m observations, and the open triangles represent the 1mm observations. J1751+096) which have conflicting classifications be- tween Fermi and CGRaBS. Some blazars found in the calibrator list have been studied extensively (e.g., 3C 279 and 3C 454.3) but the SMA blazars have not been studied collectively. Forty-four of the objects in our total blazar sample were detected by Fermi and can be found in the cata- log of LAT Bright AGN Sources (LBAS) from Abdo et al. [7]. J0050-094 has no redshift in either the LBAS catalog or CGRaBS and is not included in our study. Of the 43 remaining sources, 14 are BL Lac objects and 29 are FSRQs, with 0 . 03 ≤ z ≤ 2 . 19. We examined submillimeter light curves for all of the SMA blazars, with observations beginning in ap- proximately 2003 (see Figure 1). Typically, the 1mm band is much more well-sampled in comparison to the 850m band, but visual inspection reveals that the reg- ularity and quality of observations vary greatly from source to source. Many of the objects exhibit non- periodic variability, either in the form of persistent, low-amplitude fluctuations or higher amplitude flar- ing behavior. Submillimeter Luminosities. Since we are pri- marily concerned with comparisons to Fermi observa- tions, we note that only 129 of the SMA blazars (23 BL Lacs and 106 FSRQs) were observed by the SMA in either band during the three months August-October 2008. For these objects, submillimeter luminosities are calculated in the standard way: where D$_{L}$ is the luminosity distance, ν$_{obs}$ is the fre- quency of the observed band, and F$_{obs}$ is the average eConf C091122 Figure 2 shows the distribution for the SMA blazars. Objects with V ≤ 0 are typically unsuitable for more We roughly characterize the level of variability of each source using the variability index from Hovatta et al. [8]: Energy Spectral Indices. We derive submillime- ter spectral energy indices from observations quasi- simultaneous with the Fermi observations. To be con- sistent with the use of α$_{γ}$ , we define spectral energy in- dex as νF$_{ν}$ = ν − α$_{S}$ and calculate α$_{S}$ from the average of the energy spectral indices over the corresponding three months. We only calculate α$_{S}$ for the 16 objects (8 BL Lacs and 35 FSRQs) with observations at both 1mm and 850 µ m during this time frame. flux (in erg cm − 2 s − 1 Hz − $^{1}$) over the three month pe- riod. We adopt a lambda cold dark matter cosmology with values of H$_{0}$ = 71 km s − 1 Mpc − $^{1}$, Ω$_{M}$ = 0 . 27, and Λ = 0 . 73. Figure 2: Variability index for our sample (top: 1mm, bottom: 850 µ m), with FSRQs as the hatched distribution and BL Lacs as the solid distribution. There is no signicant difference in the class distributions in either band; the “tail” to the left is populated by objects with errors larger than the intrinsic variability. 3. VARIABILITY ANALYSIS 3.1. Variability Index 2.1. Submillimeter Properties ν$_{e}$L$_{ν}$$_{e}$ = 4 πD 2 L ν$_{obs}$F$_{obs}$ 1 + z , (1) V = ( F$_{max}$ − σ$_{F}$$_{max}$ ) − ( F$_{min}$ + σ$_{F}$$_{min}$ ) ( F$_{max}$ − σ$_{F}$$_{max}$ ) + ( F$_{min}$ + σ$_{F}$$_{min}$ ) (2)