The DECi-hertz Interferometer Gravitational-Wave Observatory (DECIGO) is a space gravitational wave (GW) detector. DECIGO was originally designed to be sensitive enough observe primordial GW background (PGW). However, due the lowered upper limit of PGW by Planck observation, further improvement target sensitivity required. In previous studies, DECIGO’s parameters were optimized maximize signal-...

In the present article, we a spectroscopic analysis of 83 field B-type stars from NOAO Indo-U.S. Library. We calculated fundamental parameters e.g effective temperatures, surface gravities, and rotational velocities using Barbier-Chalonge-Divan (BCD) method line blanketed LTE/NLTE model atmospheres. The projected velocity was estimated by fitting Mg II4481 {\AA} profile with theoretical lines m...

Abstract Reliable fundamental parameters of star clusters such as distance modulus, metallicity, age, extinction, and binary fraction are key importance for astrophysical studies. Although a lot new were identified from the data of, e.g., Gaia Data Release 2 (Gaia DR2), many not determined reliably. This work makes use photometry DR2 good color–magnitude diagram (CMD) analysis tool, Powerful CM...