WFIRST

WFIRST Simulations


Wide-Field Infrared Survey Telescope

Brown Dwarf Spectra Useful as Proxies for Exoplanet Spectra


Summary

The IFS component of the CGI will observe exoplanets across the visible spectrum. Although these exoplanets will be observed in reflected light, the transmission spectra of cold brown dwarfs can serve as proxies for exoplanets because both sets of objects share many of the same intrinsic spectral features.

These observational spectra extend into the near-infrared (~2.5 μm). Redder wavelengths are included so that these same spectra can be used to synthesize colors in the filter sets being designed for the WFI.


Observational Spectra


Spectra from the 2MASS and WISE Brown Dwarf Teams

This is a collection of nineteen observed brown dwarf spectra running from mid-L (~1700K) to late-T (~600K) spectral types. These data have been corrected for the effects of telluric absorption across all wavelengths and therefore approximate how spectra of these objects would appear from a space-based platform. These data, which originated from separate optical and near-infrared ground-based instruments, were flux calibrated separately and then rescaled, if necessary, so that fluxes match over the wavelength region in common (generally 0.95-1.05 μm). The flux calibration itself was then multiplied by a slit-loss correction factor so that synthesized near-infrared J, H, K values would match the observed 2MASS (or other published) photometry, as listed in the headers of each file.

If you find these spectra useful, we ask that you credit the original publication references listed in the table below and also in the file headers.

(Left) Observational spectra of a sequence of T dwarfs in the far optical region. Prominent features, particularly those of water and methane, are marked. (Right) A full spectrum of one object in the set, shown in both linear and logarithmic flux units.

Object Name and Spectrum Opt. Sp. Type NIR Sp. Type Ref. for Opt. Spec. Ref. for NIR Spec. Quicklook
2MASS J18212815+1414010 L4.5 L5 pec Looper et al. (2008) Looper et al. (2008) PNG
2MASS J21481633+4003594 L6 L6.5 pec Looper et al. (2008) Looper et al. (2008) PNG
2MASS J21265916+7617440 L7 T0 pec Kirkpatrick et al. (2010) Kirkpatrick et al. (2010) PNG
SDSSp J085758.45+570851.4 L8 L8 Kirkpatrick et al. (2008) Burgasser et al. (2010) PNG
SDSSp J083008.12+482847.4 L8 L9 Kirkpatrick et al. (2008) Burgasser et al. (2008) PNG
Gliese 337CD L8 T0 Kirkpatrick et al. (2008) Burgasser et al. (2010) PNG
SDSSp J083717.22-000018.3 T0 T1 Kirkpatrick et al. (2008) Burgasser et al. (2006) PNG
SDSSp J125453.90-012247.4 T2 T2 Kirkpatrick et al. (2008) Burgasser et al. (2004) PNG
2MASS J12095613-1004008 T3.5 T3 Kirkpatrick et al. (2008) Burgasser et al. (2004) PNG
SDSS J102109.69-030420.1 T3.5 T3 Kirkpatrick et al. (2008) Burgasser et al. (2006) PNG
2MASS J05591914-1404488 T5 T4.5 Burgasser et al. (2003) Burgasser et al. (2006) PNG
2MASS J15031961+2525196 T6 T5 Burgasser et al. (2003) Burgasser et al. (2004) PNG
WISEPA J101905.63+652954.2 T7 T6 Kirkpatrick et al. (2011) Kirkpatrick et al. (2011) PNG
WISEPC J234026.62-074507.2 T7 T7 Kirkpatrick et al. (2011) Kirkpatrick et al. (2011) PNG
WISEPC J145715.03+581510.2 T8 T7 Kirkpatrick et al. (2011) Kirkpatrick et al. (2011) PNG
2MASSI J0415195-093506 T8 T8 Kirkpatrick et al. (2008) Burgasser et al. (2004) PNG
WISEPA J161705.75+180714.3 T8 T8 Kirkpatrick et al. (2011) Burgasser et al. (2011) PNG
WISEPA J165311.05+444423.9 T8 T8 Kirkpatrick et al. (2011) Kirkpatrick et al. (2011) PNG
WISEPA J174124.26+255319.5 T9 T9 Kirkpatrick et al. (2011) Kirkpatrick et al. (2011) PNG
zip file of all spectra PDF