Near infrared observations of DR 18, a HII region in the Cygnus X molecular complex, are presented in this paper. These observations reveal DR 18 as an arc-shaped nebula in the 2.2 μm region, with a central star of V = 15.6 obscured by AV ' 8 magnitudes. Visible and near-infrared spectroscopy and photometry indicate a spectral type around B0.5V for this star, while a near-infrared color-color d...

In this work, we numerically study laminar flows in forced convection a U -shaped channel. Our was based on finite volume method by the fluent code carried out for Reynolds number varying range 100<Re<700, and Rayleigh Ra=105 Prandtl Pr=0.72. As function of number, results obtained are presented form thermal dynamic field, variation Nusselt speed average temperature at outlet channel as R...

As an amendment to a CRADA (Cooperative Research and Development Agreement) between Forschungszentrum Dresden (FZD) and JLab we have fabricated and tested after appropriate surface treatment a 1.6 cell, 1300 MHz RRR niobium photo-injector cavity to be used in a demonstration test at HZB. Following a baseline test at JLab, the cavity received a lead spot coating of ~8 mm diameter deposited with ...

Abstract Optical feedback is a powerful technique to stabilise and narrow semi-conductor lasers. As step forward for field deployable, ultra-stable yet tunable sources, we analyse model the opto-mechanical design of V-shaped cavity optical (VCOF) reference cavity. We estimate relative contributions sources external disturbance on resonance frequency cavity, ultimately define minimal thermal mec...