Hα Measurements Using DEFPOS/RTT150 Telescope: Instrumentation and Observations

Abstract To investigate physical properties of HII regions and some PNe about 4 ′ in size, DEFPOS Fabry-Perot spectrome-ter has been redesigned and set up at coude ́ exit of the 150 cm RTT150 telescope (f/48) at TUBITAK National Observatory (Antalya/Bakırlıtepe, Turkey). Spectrometer has a 4 ′ circular field of view and a velocity resolution of 27.27 kms−1 (a spectral re-solving power of 11.000) over a 200 kms−1 spectral window near Hα. This work presents the details of the newly redesigned instru-ment for coude ́ observations, the data reduction techniques and finally presents some physical results of our new Hα observations selected from Reynolds et al. (2005) plus Fich et al. (1990) papers. DEFPOS system has been fully tested and first observations of HII regions and PNe in the Galaxy are used to illustrate the power of the instrument. We feel that our first Fabry-Perot observations can provide a powerful tool for the study of small angular size objects. In future, we are planning to prepare a catalogue including same physical properties such as radial velocity, line width, and inten-sity of some PNe and HII regions close to 4 ′ field of view