We obtained medium-resolution spectra of the bonafide brown dwarf Cha Hα 1, the five brown dwarf candidates Cha Hα 2 to 6, two additional late M-type brown dwarf candidates, all originally selected by Hα emission, and four previously known T Tauri stars, all located in Chamaeleon I. The spectral types of our targets range down to M8. We show their spectra and also list their IJK magnitudes from...

We present intermediate dispersion (0.7-2.2 Å pix) optical spectroscopic observations aimed at applying the “Lithium Test” to a sample of ten brown dwarf candidates located in the general field, two in young open clusters, and two in close binaries. We find evidence for strong Li depletion in all of them, and thus infer lower mass limits of 0.065 M⊙, depending only slightly (±0.005 M⊙) on the i...

We carried out time-resolved photometric observations of an SU UMa type dwarf nova, BC UMa, during its superoutburst in February 2003. We detect early superhumps ( or outburst orbital humps) during the first two days of the outburst. The period of early superhumps is 0.06258(13) d and the amplitude is 0.04 mag. After the early superhump phase, common superhumps with an amplitude of 0.3 mag and ...

ABSTRACT- Growth retardants are natural or synthetic chemical substances which are directly applied to crops to alter some structural processes. It is expected that these alterations modify hormonal balance and growth leading to increased yield, improved crop quality or facilitated harvesting. Cycocel (CCC) or chlormequat chloride (2-chloro ethyl trimethyl ammonium chloride) as a synthetic grow...