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Astronomical Data Analysis Software and Systems X ASP Conference Series, Vol. 238, 2001 F. R. Harnden Jr., F. A. Primini, and H. E. Payne, eds.

Development of Radio Astronomical Data Reduction Software NEWSTAR
Miho Ikeda, Kota Nishiyama Japan Science and Technology Corporation, Honchou, Kawaguchi, Saitama 332-0012, Japan Masatoshi Ohishi National Astronomical Observatory, Osawa, Mitaka, Tokyo 181-8588, Japan Ken'ichi Tatematsu Nobeyama Radio Observatory, Nobeyama, Minamimaki, Minamisaku, Nagano, 384-1305, Japan Abstract. NEWSTAR was developed for processing data from the 45m radio telescope of the Nobeyama Radio Observatory (NRO). Based on AIPS, and developed under Solaris and IRIX, NEWSTAR has been expanded to include LINUX and HP-UX versions that have considerably improved the reduction performance of NRO observational data.

1.

Introduction

NEWSTAR is a radio astronomical data reduction package for the 45-m radio telescope and the Nobeyama Millimeter Array (NMA) of the Nobeyama Radio Observatory (NRO), Japan. Since NEWSTAR was originally developed for data reduction within NRO on Solaris, Sun and IRIX platforms, users wanting offsite access to NEWSTAR formerly had to obtain computers similar to those at NRO or access NRO machines remotely. In order to improve this situation, LINUX and HP-UX versions of NEWSTAR were created, giving users access to NEWSTAR virtually anywhere. 2. Structure of NEWSTAR

NEWSTAR consists of an AIPS core plus the original application. The AIPS core provides file management, mapping processes for interferometer data, and so on. The original application was designed to reduce spectral data obtained by the 45-m telescope and make data cubes from the spectral data. Users can also reduce UV-data of the NMA using NEWSTAR before further processing with AIPS. NEWSTAR also adds graphical user interfaces (GUIs). Users can input parameters for each task from the GUI, and the parameters are saved, obviating the need for learning native AIPS commands and permitting NEWSTAR use 522 c Copyright 2001 Astronomical Society of the Pacific. All rights reserved.


Development of Radio Reduction Software NEWSTAR

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Figure 1. NEWSTAR has several window panels, e.g., the TaskSelection panel (bottom left), a parameter-input window (top center) and the Tektronics window (bottom right). easily without references. (Users can use still invoke native AIPS commands from the AIPS window.) 3. UIs

NEWSTAR has several window panels, samples of which are shown in Figure 1. The Task-Selection panel lists tasks included in NEWSTAR, and users can select tasks from this panel. Each task has a parameter-input window. Users can see mapping points and a list of files from this panel. The Tektronics window displays spectra and/or maps. NEWSTAR also has an AIPS window permitting users to execute native AIPS commands. From the "File List" window, users can list, delete, rename and backup data files. 4. Treatment of data

The flow of the data reduction of NEWSTAR is shown in Figure 2. Raw data obtained by the 45-m telescope are saved through the archival system. The saved data are under AIPS control. Users can craete spectra by integrating the raw data, make map data (cube data) from the spectra, and handle them again by using several AIPS tasks.


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Ikeda, Nishiyama, Ohishi, and Tatematsu

Figure 2. NEWSTAR data reduction flow under Solaris (left side) and LINUX (right side) At NRO, Solaris 2.7 is adopted as the operating system of the workstations for data reduction. When users continue data reduction using NEWSTAR on other operating systems, difference of data endian should be considered. For example, in the case of LINUX, it is necessary to convert from big to little endians. The flow of the data reduction in the LINUX version is shown in the right side of Figure 2. The raw data transfered from the NRO archival system are transformed by task "NEW ARCHV.EXE" for LINUX. The data endian is transformed at that time. The spectral data and the map (cube) data made in the Solaris NEWSTAR are transformed to FITS files, and the FITS files are read using the LINUX version of NEWSTAR. Conversely, FITS file made in the LINUX version can be reduced under Solaris NEWSTAR. For other operating systems, the flow of the data reduction is similar to that above. 5. Summary

The NEWSTAR radio astronomical data reduction software was originally developed for data reduction within NRO. By porting it to LINUX, HP-UX, and IRIX, users now have access to its data reduction capabilities in their home institutions, and the performance of NRO data reduction software has be considerably improved. Acknowledgments. The authors would like to thank Jun Maekawa and Kiyohiko Yanagisawa for giving very useful advice. This research is supported by "Research and Development Applying Advanced Computational Science and Technology" of Japan Science and Technology Corporation.