To investigate the physical properties of HII regions and some PNe about 4 in size, a DEFPOS Fabry-Perot spectrometer has been redesigned and set up at the coudé exit of the 150 cm RTT150 telescope (f/48) at TUBITAK National Observatory (Antalya/Bakırlıtepe, Turkey). The spectrometer has a 4 circular field of view and a velocity resolution of 27.27 km s −1 (a spectral resolving power of 11 000) over a 200 km s −1 spectral window near Hα. This work presents the details of the newly redesigned instrument for coudé observations, the data reduction techniques and finally presents some physical results of our new Hα observations selected from the Reynolds et al. (2005) and Fich et al. (1990) papers. The DEFPOS system has been fully tested and the 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 objects with small angular size. In the future, we are planning to prepare a catalog including some physical properties such as radial velocity, line width, and intensity of some PNe and HII regions close to the 4 field of view.

In this paper, the natural radioactivity levels in a total of 117 samples of 14 different building materials collected from building construction sites and from the retailers in Adana were studied by means of gamma-ray spectrometer with HPGe detector. The mean activity concentrations of 226 Ra, 232 Th and 40 K measured in the studied building material samples ranged from 2.1 to 88.2 Bq kg À1 , 1.8 to 52.7 Bq kg À1 and 68.1 to 847.5 Bq kg À1 for 226 Ra, 232 Th and 40 K radionuclide, respectively. The external and internal index, the indoor absorbed dose rate and the corresponding annual effective dose were evaluated for potential exposure risks from the usage of the building material samples. The evaluated values of the external and internal index were below the recommended upper level. All the values of effective annual dose determined were lower than recommended exemption level of 0.3 mSv. The results suggest that the use of the studied building material samples in the construction of buildings is unlikely to give rise to any significant radiation exposure to the residents.

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Instrumental improvements in sensitivity of Fabry-Perot spectrometers with the development of Charged Coupled Device (CCD) cameras enable measurement of faint emission lines. A Dual Etalon Fabry-Perot OpticalSpectrometer (DEFPOS) has recently been built to observe hydrogen Balmer alpha ( Hα : 6563 Å) emission lines from the Earth's upper atmosphere and the interstellar medium in our Galaxy. This spectrometer is now located at TUBITAK National Observatory (TUG), Antalya, Turkey, and has been observing in the zenith direction with a field-of-view of 4°.76 and with 1200 s exposure time. This paper briefly describes the DEFPOS spectrometer, data analysis, and results from data taken on 47 nights between 2002 and 2004. For the averaged geocoronal Balmer α intensities measured in nighttime, we found that the intensity was generally greater than 1 R and less than 12 R. These first results show that there is agreement with the theory and measurements made by other groups regarding the geocoronal Balmer α intensities. DEFPOS observations from Turkey offer potential to combine with geocoronal hydrogen observations at other locations such as Arecibo, Puerto Rico, Wisconsin Pine Bluff Observatory (PBO), and WHAM, Kitt Peak, Arizona, enhancing our global knowledge of the upper atmosphere. In the near future, DEFPOS will be used at coudé exit of the 150 cm telescope. Then, it will be able to make more accurate observations at any direction in the sky.(