WEATHER ON THE NEAREST BROWN DWARFS: RESOLVED SIMULTANEOUS MULTI-WAVELENGTH VARIABILITY MONITORING OF WISE J104915.57–531906.1AB

Journal Article · Wed Nov 20 00:00:00 EST 2013 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/778/1/L10· OSTI ID:22364130

Biller, Beth A.; Crossfield, Ian J. M.; Mancini, Luigi; Ciceri, Simona; Kopytova, Taisiya G.; Bonnefoy, Mickaël; Deacon, Niall R.; Schlieder, Joshua E.; Buenzli, Esther; Brandner, Wolfgang; Bailer-Jones, Coryn A. L.; Henning, Thomas; Goldman, Bertrand ^[1]; Southworth, John ^[2]; Allard, France; Homeier, Derek; Freytag, Bernd ^[3]; Greiner, Jochen ^[4]

---

1. Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany)
2. Astrophysics Group, Keele University, Staffordshire, ST5 5BG (United Kingdom)
3. Centre de Recherche Astrophysique de Lyon, Ecole Normale Supérieure de Lyon, 46 allée d'Italie, F-69364 Lyon cedex 07 (France)
4. Max-Planck Institute for extraterrestrische Physik, D-85748 Garching, Giessenbachstr (Germany)

We present two epochs of MPG/ESO 2.2 m GROND simultaneous six-band (r'i'z' JHK) photometric monitoring of the closest known L/T transition brown dwarf binary WISE J104915.57–531906.1AB. We report here the first resolved variability monitoring of both the T0.5 and L7.5 components. We obtained 4 hr of focused observations on the night of 2013 April 22 (UT), as well as 4 hr of defocused (unresolved) observations on the night of 2013 April 16 (UT). We note a number of robust trends in our light curves. The r' and i' light curves appear to be anti-correlated with z' and H for the T0.5 component and in the unresolved light curve. In the defocused dataset, J appears correlated with z' and H and anti-correlated with r' and i', while in the focused dataset we measure no variability for J at the level of our photometric precision, likely due to evolving weather phenomena. In our focused T0.5 component light curve, the K band light curve displays a significant phase offset relative to both H and z'. We argue that the measured phase offsets are correlated with atmospheric pressure probed at each band, as estimated from one-dimensional atmospheric models. We also report low-amplitude variability in i' and z' intrinsic to the L7.5 component.

• OSTI ID: 22364130
• Journal Information: Astrophysical Journal Letters, Vol. 778, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCURACY
AMPLITUDES
ASTRONOMY
ASTROPHYSICS
ATMOSPHERIC PRESSURE
BINARY STARS
DATASETS
DIAGRAMS
DWARF STARS
MASS
PHOTOMETRY
PROBES
STARS
VISIBLE RADIATION
WAVELENGTHS