OCTOCAM researchers will be able to use
gamma-ray bursts to explore the earliest
star formation events in the Universe (Figure
1). It will also be ideal for following up and
characterizing kilonova signatures of neu-
tron star mergers, and likely counterparts of
gravitational wave sources
OCTOCAM will allow effective broadband
timing studies or reverberation mapping
of X-ray binaries and active galactic nuclei
(AGN) to constrain the physical size of the
emission regions around their black holes,
measure the mass of their black holes, and
give new insights into accretion physics
near the event horizon. For AGN, the wide
wavelength coverage will allow observers
to study these systems over a broad red-
shift range. OCTOCAM will also be able to
make a significant impact in the studies of
tidal disruption events (TDEs) — material
being blown away from a black hole after it
rips a star apart. Rapid broadband follow-up
observations will also provide unparalleled
probes of the regions close to the black hole,
and ultimately allow measuring their mass
and possibly their spin.
Simultaneous spectral coverage is also cru-
cial for characterizing variable, but non-tran-
sient, objects. Such objects include asteroids
where the rotation affects the colors derived
if the observations are not obtained at the
same time, and
pre-main sequence
stellar
objects
where star spots
and accretion disks
can heavily affect
the derived colors.
OCTOCAM’s field-
of-view will ensure
suitable reference
objects for any re-
gion
observed.
Having simultane-
ous imaging in all
January 2018 / 2017 Year in Review
of OCTOCAM’s eight bands enables users to
determine the photometric redshift of high
z objects, making the instrument efficient in
rapidly identifying drop-out objects across
the full field-of-view.
OCTOCAM has a strong and diverse science
team led by Project Scientist Alexander van
der Horst from The George Washington Uni-
versity. Many other science cases were iden-
tified for OCTOCAM; for further details see
our website here.
OCTOCAM Instrument Design
Each of OCTOCAM’s eight arms is an imag-
ing spectrograph, based on the use of high-
efficiency dichroics to split the light. The
GeminiFocus
Figure 1.
Photometry and
spectroscopy of the most
distant spectroscopically
confirmed GRB to date
(Tanvir et al., Nature, 461:
1254, 2009). The spectrum
shows there is little
dust in the host galaxy,
consistent with a low
metallicity. OCTOCAM
will be an ideal tool for
obtaining similar data
sets very efficiently.
Figure 2.
Spectra of the trans-
Neptunian dwarf planet
Eris with deep
absorption features
due to CH 4 ice (Alvarez-
Candal et al., A&A, 532:
A130, 2011), and the
centaur 2008 YB3 with
no apparent absorption
features (Pinilla-Alonso
et al. , A&A, 550: A13,
2013). Also shown
are the approximate
positions and width
of some photometric
filters of OCTOCAM.
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