Overview
On this page we include a set of plots detailing WFC3 usage statistics for GO (General Observer) observations over time. For more information regarding WFC3 channels and filters, please refer to the WFC3 Instrument Handbook.
Usage Statistics Plots
The frequency of WFC3 IR and UVIS channel (and filter) usage has changed over time, as demonstrated by Figures 1-4. In Figure 1, a heatmap plot, yearly WFC3 usage is normalized against the total exposure time within each respective channel, so that each column in the heatmap sums to 100% usage. Thus, these plots show, at a glance, how the amount of WFC3 usage within the channel or filter has changed over a ~14 year time period. Figures 2-4 provide a more direct comparison of usage between the channels or filters.
Figure 1: WFC3 Channel and Filter Usage Heatmaps. WFC3/IR usage peaked in 2015 at 10.52% of total exposure time. Its usage decreased by ~70% in 2022 at only 2.85%. Notably, we see that IR usage dropped by half between 2016 and 2017 (from 10.16% to 5.26% of all IR usage), remaining relatively constant before 2016 and further decreasing after 2018. Meanwhile, WFC3/UVIS usage has increased over time. UVIS channel usage increased from 2010 at 5.71% to peaking in 2020 with 8.29% of all UVIS usage (a ~45% relative increase). Generated on October 25th, 2023. Click here for updated WFC3 Channel and Filter Usage Heatmaps.
Figure 2: WFC3 Channel and Filter Usage Bar Charts. Over the entire lifetime of the WFC3 instrument, the UVIS channel was used ~49% of the time and the IR channel the other 51%. The distribution of usage between the UVIS and IR channels has varied with time, with IR usage dominating from 2009 to 2016 and UVIS taking over after 2018. This pattern is consistent with the trends suggested by the WFC3 Channel Usage Heatmap. Generated on October 25th, 2023. Click here for updated WFC3 Channel and Filter Usage Bar Charts.
Figure 3: WFC3 IR Filter Usage Bar Charts by Year. IR filter usage varies year-to-year. Overall, the G141 grism filter and F160W wide filter have had the highest rates of usage in GO observations with WFC3. Generated on October 25th, 2023. Click here for updated WFC3 IR Filter Usage Bar Charts by Year.
Figure 4: WFC3 UVIS Filter Usage Bar Charts by Year. While UVIS filter usage rates vary year-to-year, F275W, F606W, and F814W wide filters have consistently had high rates of usage in GO observations with WFC3. Generated on October 25th, 2023. Click here for updated WFC3 UVIS Filter Usage Bar Charts by Year.