A Pipeline for the ROTSE-IIId Archival Data

We have constructed a new, fast, robust and reliable pipeline to detect variable stars from the ROTSE-IIId archival data. Turkish share of ROTSE-III archive contains approximately one million objects from a large field of view (1.85\dgr) and it considerably covers a large portion of northern sky (\delta>-25\dgr). The unfiltered ROTSE-III magnitude of the objects ranges from 7.7 to 16.9. The main stages of the new pipeline are as follows: Source extraction, astrometry of the objects, light curve generation and inhomogeneous ensemble photometry. A high performance computing (HPC) algorithm has also been implemented into the pipeline where we had a good performance even on a personal computer. Running the algorithms of the pipeline on a cluster decreases analysis time significantly from weeks to hours. The pipeline is especially tested against long period variable stars with periods of a few hundred days (e.g Mira and SR) and variables having periods starting from a few days to a few hundred days were detected.Comment: 8 pages, 5 figures 2 tables; last revision before publishe

NATO Advanced Study Institute on the Electromagnetic Spectrum of Neutron Stars

Neutron stars hold a central place in astrophysics, not only because they are made up of the most extreme states of the condensed matter, but also because they are, along with white dwarfs and black holes, one of the stable configurations that stars reach at the end of stellar evolution. Neutron stars posses the highest rotation rates and strongest magnetic fields among all stars. They radiate prolifically, in high energy electromagnetic radiation and in the radio band. This book is devoted to the selected lectures presented in the 6th NATO-ASI series entitled "The Electromagnetic Spectrum of Neutron Stars" in Marmaris, Turkey, on 7-18 June 2004. This ASI is devoted to the spectral properties of neutron stars. Spectral observations of neutron stars help us to understand the magnetospheric emission processes of isolated radio pulsars and the emission processes of accreting neutron stars. This volume includes spectral information from the neutron stars in broadest sense, namely neutrino and gravitational radiation along with the electromagnetic spectrum. We believe that this volume can serve as graduate level of text including the broad range of properties of neutron stars

Emission Lines of Northern Planetary Nebulae

In this work, we present results of long slit spectrophotometric emission line flux observations of selected planetary nebulae (PNe). We have measured absolute fluxes and equivalent widths (EW) of all observable emission lines. In addition to these observations, electron temperatures (Te), densities (Ne), and chemical abundances were also calculated. The main purpose of this work is to fill the gaps in emission line flux standards for the northern hemisphere. It is expected that the measured fluxes would be used as standard data set for further photometric and spectrometric measurements of HII regions, supernova remnants etc

Design of a derotator for the 4 m DAG telescope

This paper summarize our work on the design of a field derotator for the adaptive optics instruments Nasmyth platform of DAG (Dogu Anadolu Gozlemevi), a new 4 m telescope for astronomical observations near the city of Erzurum, Turkey. While the telescope follows an astronomical object, its pupil sees a rotation of the object around the optical axis which depends on the telescope geographic coordinate and the object sky coordinate. This effect is called the field rotation. This rotation needs to be compensated during the astronomical object data acquisition. In this report we demonstrate the feasibility of placing the derotator (a K-mirror design) in the telescope fork central hole and propose a preliminary design, considering flexures

A microwave kinetic inductance detector for the DAG telescope

We present the details of a proposed microwave kinetic inductance detector (MKID) for the DAG (Eastern Anatolia Observatory in Turkish) telescope, DAG-MKID. The observatory will have a modern 4m size telescope that is currently under construction. Current plan to obtain the first light with the telescope is late 2019. The proposed MKID based instrument will enable astronomers to simultaneously detect photons in the relatively wide wavelength range of 4000-13500 Å with a timing accuracy of μs and spectral resolution R = /▵ =10-25. With a planned field of view of approximately an arcminute, DAG-MKID will mostly be used for follow-up observations of transient or variable objects as well as a robust tool to measure photometric redshifts of a large number of galaxies or other extra-galactic objects.Publisher's Versio

Dünyada Astronomik Yer Seçimi Çalışması

Teknolojinin geli¸smesi, astronomik alanda b¨uy¨uk teleskopların ¨uretimini hızlandırmı¸stır. Uretilen teleskoplardan maksimum ¨ verimin alınabilmesi i¸cin yerle¸skenin en uygun ko¸sullara sahip olması gerekmektedir. D¨unya ¨uzerinde astronomik a¸cıdan uygun yerlerin belirlenebilmesi i¸cin etkin fakt¨orlerin (y¨ukseklik, bulutluluk, ı¸sık kirlili˘gi, su buharı miktarı, Atmosferde bulunan Aerosol miktarı vb.) niceliksel ve konumsal olarak analizi ile uzun d¨onemli meteorolojik yer verileri gerekmektedir. Bu fakt¨orleri temsil eden sayısal verilerin temin edilmesi, d¨uzenlenmesi, standardizasyonu, entegrasyonu ve analizlerinin ise geleneksel y¨ontemlerden ziyade Uzaktan Algılama ve Co˘grafi Bilgi Sistemleri (CBS) yardımıyla ¸cok daha hızlı, ekonomik ve etkin bir ¸sekilde ger¸cekle¸stirilebilmektedir. Aksaker ve ark. (2015) tarafından T¨urkiye i¸cin ger¸cekle¸stirilen ve etkin ¸cıktılar ¨ureterek tecr¨ube kazanımı sa˘glanan b¨oyle bir yakla¸sımın, bu ¸calı¸sma ile global ¨ol¸ce˘gi hedeflenmi¸stir. Bu ¸calı¸smada; D¨unya ¨uzerinde Optik/Kızıl¨ote b¨olgede ¸calı¸sabilecek teleskoplar i¸cin en uygun yerler belirlenmesi, var olan g¨ozlemevlerinin durumu kar¸sıla¸stırmalı olarak ortaya ¸cıkarılması ve yeni bir g¨ozlemevi kurmak isteyen ¨ulkeler, ara¸stırma merkezleri ve ¨universiteler i¸cin g¨uncel veriler CBS-C¸KKA (Co˘grafi Bilgi Sistemi-C¸ok Kriterli Karar Analizi) ile yapılmı¸stır. Sonu¸cta d¨u¸s¨uk ¸c¨oz¨un¨url¨uk ve 1 yıllık ar¸siv verileri kullanılarak D¨unyada g¨ozlemevleri i¸cin uygun yerler belirlenmi¸stir. Buna g¨ore Antarktika, Amerikanın batı kıyıları, Gr¨onland, Afrikanın do˘gusunda bir ka¸c b¨olge ve Hindistan-C¸in arasındaki da˘glık b¨olgeler uygun yerlerdir