MuSCAT2 is an instrument that has been offered at the Carlos Sánchez Telescope since 2018. It has been developed by the Center for Astrobiology and the University of Tokyo (P.I. Norio Narita) in collaboration with the IAC (P.I. Enric Palle). It allows simultaneous photometry in the g (400 to 550 nm), r (550 to 700 nm), i (700 to 820 nm) and zs (820 to 920 nm) bands. 146 nights a year are reserved for the team that developed the instrument, but MuSCAT2 is offered as a common user instrument, following the rules of other CAT telescopes. Applicants should note that some targets related to extrasolar planets are protected.
The article MuSCAT2: four-color simultaneous camera for the 1.52-m Telescopio Carlos Sánchez, where all the relevant information about this instrument appears, is available at:
The optical system of MuSCAT2 is composed of F-conversion lenses (lens-1 and lens-2) to widen the field-of-view (FoV) and dichroic mirrors (DMs) to separate the light into four-wavelength bands.
You can find a technical description of the cameras in this document.
Pixel size:-0.434 “/px for g and r (7.41 arcmin x 7.41 arcmin)
-0.435 “/px for i (7.43 arcmin x 7.43 arcmin)
-0.436 “/px for zs (7.44 arcmin x 7.44 arcmin)
MuSCAT2 is equipped with a grizs filter set, located on channel 1 to 4, respectively.
The total transmittance of the MuSCAT2 instrument, including all optics and quantum efficiency of the detectors, is plotted in the figure below.
Basic reduction (dark images subtraction and flatfield correction) is performed at the end of each night. Observers will have access to to both raw and pre-reduced data.
The following figure can be used as an estimator of the exposure time as a function of the target’s magnitude.
While developing a dedicated ETC, we remind users that the “mov” command can be used to acquire tests images to check the flux level. The limiting quantities of MuSCAT2 that give a signal-to-noise ratio (S/N) of 10 with a 10-minute exposure are g′lim=20.5mag, r′lim=20.5mag, i′lim=19.7mag, and z′lim=19.0mag.
List of representative papers (more papers can be found here)
Peterson et al. 2023, Nature, Volume 617, Issue 7962, p.701-705
A temperate Earth-sized planet with tidal heating transiting an M6 star
Trifonov et al. 2021, Science, Volume 371, Issue 6533, pp. 1038-1041
A nearby transiting rocky exoplanet that is suitable for atmospheric investigation
Vanderburg et al. 2020, Nature, Volume 585, Issue 7825, p.363-367
A giant planet candidate transiting a white dwarf
– Solar System Small Bodies
Slivan et al. 2023, Icarus, Volume 405, article id. 115701
Spin vectors in the Koronis family: V. Resolving the ambiguous rotation period of (3032) Evans
Pinilla-Alonso et al. 2022, The Planetary Science Journal, Volume 3,
Issue 12, id.267
Detection of the Irregular Shape of the Southern Limb of Menoetius from Observations of the 2017-2018 Patroclus-Menoetius Mutual Events
Maas et al. 2022, Astronomy & Astrophysics, Volume 668, id.A111
Lower-than-expected flare temperatures for TRAPPIST-1
Tampo et al. 2020, Publications of the Astronomical Society of Japan,
Volume 72, Issue 3, id.49
First detection of two superoutbursts during the rebrightening phase of a WZ Sge-type dwarf nova: TCP J21040470+4631129
M57, a composition of gri images, 10s exposures
Example light curve of Wasp-12b, observed during commissioning. The precision of photometry reaches 629 ppm (g), 616 ppm (r), 834 ppm (i) and 1166 ppm (z).
Part of the developer team during the installation of MuSCAT2.