GeminiFocus 2014 Year in Review | Page 39

it from responding correctly, was fixed. The mirror is now working fine. The science-fold mirror was also tuned for correct movement between all the different focal stations, and measurements were taken to consider the feasibility of purchasing a spare. Gemini Planet Imager Commissioning Run The fourth and final planned commissioning run for the Gemini Planet Imager (GPI) was successfully completed during the first half of September. Extensive testing in the lab and on the flexure rig — to fully stress test the instrument — preceded the commissioning run, as there has been extensive work in both software and hardware. The hardware changes address heating issues in the electronics cabinet and also that with vibrations from both the telescope structure and the robust electronics within the imager itself. Software updates focused on improving instrument performance and allowing a smooth transition from commissioning into science operations. The latest commissioning run had several major goals: to stress test the instrument’s science operation integration; to dampen vibrations by modifying the adaptive optics control loops; to ameliorate the effects of vibration on the science images; to estimate the contrast on various targets under the offered conditions in the queue; and to evaluate the effect of the improvements since the last commissioning run. GPI is now being offered in 2014B. GMOS Back for Science at Gemini South The Gemini Multi-Object Spectrograph (GMOS) is back at work for imaging, taking science data with the new Hamamatsu CCDs. As expected, the Hamamatsu CCDs are significantly more sensitive in the red, January 2015 and appear to perform as advertised from the delivered QE curves pending final spectral throughput analysis. The new CCDs have also greatly reduced fringing, being now about 2 to 3 percent at 900 nanometers (compared to ~ 65 percent for the previous detectors). As you might recall, a decision was made in late 2012 to upgrade the GMOS-South detectors with the newly developed highly-sensitive CCDs manufactured by Hamamatsu Photonics. After an extensive period of testing in Hilo, the new detector array was shipped to Chile last April and installed in late May. The array then underwent commissioning during the following two months — including solving some electronics issues on the controllers. Figure 4. Images from GMOS, showing a direct comparison between i’-band imaging of the same field (E2V on the left, Hamamatsu on the right). These are raw, unprocessed images, which show how the Hamamatsu CCDs greatly reduce fringing. As of the start of Semester 2014B, the new CCDs are operating at full capacity. The screenshot (Figure 4) shows a direct comparison between i’-band imaging of the same field (previous E2V detector on the left, Hamamatsu on the right). These raw, unprocessed images, should help you to appreciate the new CCDs’ great reduction in fringing. FLAMINGOS-2 Observations Start Observations for 2014B programs with FLAMINGOS-2 (F-2) have started, with a healthy distribution of 12 progr