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arXiv · astro-ph/0110340

5-micron photometry of late-type dwarfs

I. N. Reid·K. L. Cruz
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Abstract

We present narrowband-M photometry of nine low-mass dwarfs with spectral types ranging from M2.5 to L0.5. Combining the (L'-M') colours derived from our observations with data from the literature, we find colours consistent with a Rayleigh-Jeans flux distribution for spectral types earlier than M5, but enhanced F_3.8/F_4.7 flux ratios (negative (L'-M') colours) at later spectral types. This probably reflects increased absorption at M' due to the CO fundamental band. We compare our results against recent model predictions and briefly discuss the implications.

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I. N. Reid, K. L. Cruz. 2001-10-15. 5-micron photometry of late-type dwarfs. https://doi.org/10.1086/338083

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