Bibcode
Strampelli, G. M.; Aguilar, Jonathan; Aparicio, A.; Piotto, Giampaolo; Pueyo, Laurent; Robberto, Massimo
Referencia bibliográfica
American Astronomical Society, AAS Meeting #231, id.#414.07
Fecha de publicación:
1
2018
Número de citas
0
Número de citas referidas
0
Descripción
We present new results relative to the population of substellar binaries
in the Orion Nebula Cluster. We reprocessed HST/WFC3 data using an
analysis technique developed to detect close companions in the wings of
the stellar PSFs, based on the PyKLIP implementation of the KLIP PSF
subtraction algorithm. Starting from a sample of ~1200 stars selected
over the range J=11-15 mag, we were able to uncover ~80 candidate
companions in the magnitude range J=16-23 mag. We use the presence of
the 1.4 micron H2O absorption feature in the companion photosphere to
discriminate 32 bona-fide substellar candidates from a population of
reddened background objects. We derive an estimate of the companion mass
assuming a 2Myr isochrone and the reddening of their primary. With 8
stellar companions, 19 brown dwarfs and 5 planetary mass objects, our
study provide us with an unbiased sample of companions at the low-mass
end of the IMF, probing the transition from binary to planetary systems.