GHOST has not yet been fully commissioned and information such as sensitivities is pending. For this reason GHOST is not offered as an instrument for regular science in 23B. We expect most modes to be fully commissioned late 23A, and for there to be a special Call for proposals in 23B. We will post an announcement as soon as we have more details on the special call in 23B.
Since November 'Alopeke has now a Halpha filter. The specifications are identical to the one installed at Zorro. The filter is available to anyone applying to 'Alopeke time.
After the GMOS-S detector troubleshooting earlier this semester, the physical location of the array has shifted by a small amount in the -direction. While this did not have harmful consequences, the Y-shift has the effect of the MOS mask slits as defined on the MDF appearing with a small (~20 pix) yet systematic offset with respect to the actual location of the spectra.
After successfully assembling and testing the spectrograph and enclosure from April through June, the team was able to observe with GHOST on-sky for only two good nights at the end of June due to poor weather conditions. A few more good nights in September resulted in further commissioning progress. Presently, the team is working on improving the data deduction pipeline software and the telescope control software to remedy issues determined during these commissioning runs. These improvements are expected to be complete by early 2023.
It has recently been noticed that the sensitivity of GMOS-N B600 observations at wavelengths blueward of 500 nm is significantly lower than predicted by the Exposure Time Calculator. Historic data of spectrophotometric standard stars show that this reduction in sensitivity is largely attributed to a decrease of the B600 grating response, which started to develop around 2013 to 2014.
IGRINS was removed today from telescope to leave way for GHOST installation. After that, IGRINS will go through a scheduled maintenance by a team from KASI, and it will back at the telescope on October 17th.
Following successful checks on Friday after the yearly engineering shutdown, IGRINS is back doing observations. The instrument will remain on the telescope until Sept 7th.
The repair attempted during July was not successful, and the problem on CCD2 (amplifier #5) persists. On the other hand, the noise patterns on CCD2 and CCD3 are gone.
The situation will remain like this during semester 22B since the only possible solution requires a major intervention, which is not planned for the current semester.
After the heavy snowtorms that affected Pachon, telescope operations have resumed, and IGRINS will be available for a short time starting tonight until the beginning of the yearly engineering shutdown.
Heavy snowfall at Cerro Pachon has completely wiped out the Zorro run originally scheduled between July 11 and 17th. We expect the telescope can be operating again on Monday 18th, and the Zorro run has been extended until Friday 22nd.