There are six main instruments currently in operation at the ARC 3.5m telescope: ARCES (Echelle): the ARC Echelle spectrograph, a high resolution (R~31,500) echelle spectrograph that observes the entire wavelength range from 3200 to 10000Å in a single image on a 2048x2048 CCD. This instrument is permanently mounted at the NA1 port. ARCTIC: the ARC Telescope Imaging Camera, a direct imager with a field of view of 7.5 arcminutes. A variety of filters are available to be placed in a 6-slot filter wheel. KOSMOS:The Kitt Peak Ohio State Multi-Object Spectrograph is a medium dispersion spectrograph (resolving power up to 2600) using grism dispersers. It was built at Ohio State and commissioned at the Kitt Peak Mayall 4-m telescope in October 2013, then later converted for use at the Apache Point Observatory ARC 3.5m Telescope NICFPS: the Near-Infrared Camera and Fabry-Perot Spectrometer, an infrared instrument that provides NIR imaging capability of a 4.5 arcmin square FOV on a 1024x1024 Rockwell Hawaii 1-RG HgCdTe detector. The instrument has a large complement of broad and narrow band filters, and includes a cold Lyot stop to reduce thermal background. TRIPLESPEC: a medium resolution IR spectrograph that will deliver spectroscopy across the JHK windows in a single exposure at R~2700. ARCES is permanently mounted at the NA1 (Nasmyth) port and Agile is mounted at the TR2 port, while the other four instruments can be mounted at the NA2 port. Switching between ports using the tertiary mirror can be accomplished in less than 5 minutes. Switching instruments at the NA2 port can be done within 15-20 minutes, allowing for the capability to do rapid instrument changes for target of opportunity observations, or to adjust to different observing conditions. In addition to the facility instruments, several visiting or non-facility instruments have been used at the 3.5m, and some of these are available to the ARC observing community by contacting the instrument PIs: APOLLO: the Apache Point Observatory Lunar Laser-Ranging Operation, an instrument that is attempting to map the orbit of the Moon by distance measurements at an accuracy of ~1mm, using a laser that is beamed up through the telescope and reflects off retroreflectors previously left on the Moon. Finally, several engineering instruments are also used: FASTCAM: a high speed (100 Hz) imaging camera used to diagnose image motion issue Puntino: a Shack-Hartmann sensor, built by SpotOptics, used for optical alignment of the telescope
There are six main instruments currently in operation at the ARC 3.5m telescope:
ARCES is permanently mounted at the NA1 (Nasmyth) port and Agile is mounted at the TR2 port, while the other four instruments can be mounted at the NA2 port. Switching between ports using the tertiary mirror can be accomplished in less than 5 minutes. Switching instruments at the NA2 port can be done within 15-20 minutes, allowing for the capability to do rapid instrument changes for target of opportunity observations, or to adjust to different observing conditions.
In addition to the facility instruments, several visiting or non-facility instruments have been used at the 3.5m, and some of these are available to the ARC observing community by contacting the instrument PIs:
Finally, several engineering instruments are also used:
