The VIRUS data reduction pipeline

The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) will measure baryonic acoustic oscillations, first discovered in the Cosmic Microwave Background (CMB), to constrain the nature of dark energy by performing a blind search for Ly-α emitting galaxies within a 200 deg2 field and a redshift bin of 1.8 < z < 3.7. This will be achieved by VIRUS, a wide field, low resolution, 145 IFU spectrograph. The data reduction pipeline will have to extract ≈ 35.000 spectra per exposure (≈5 million per night, i.e. 500 million in total), perform an astrometric, photometric, and wavelength calibration, and find and classify objects in the spectra fully automatically. We will describe our ideas how to achieve this goal.

[1]  Andreas Kelz,et al.  PMAS: The Potsdam Multi-Aperture Spectrophotometer. II. The Wide Integral Field Unit PPak , 2006 .

[2]  R. Lupton,et al.  Astrometric Calibration of the Sloan Digital Sky Survey , 2002, astro-ph/0211375.

[3]  D. Wells,et al.  Fits: a flexible image transport system , 1981 .

[4]  H Germany,et al.  PMAS: The Potsdam Multi‐Aperture Spectrophotometer. I. Design, Manufacture, and Performance , 2005, astro-ph/0502581.

[5]  S. Noll,et al.  The evolution of the luminosity functions in the FORS Deep Field from low to high redshift: I. The blue bands , 2004, astro-ph/0403535.

[6]  Niall Gaffney,et al.  Early performance and present status of the Hobby-Eberly Telescope , 1998, Astronomical Telescopes and Instrumentation.

[7]  K. Abazajian et al..  The Third Data Release of the Sloan Digital Sky Survey , 2004 .

[8]  A. W. V. Erheijen,et al.  Pmas: the Potsdam Multi Aperture Spectrophotometer. Ii. the Wide Integral Field Unit Ppak , 2005 .

[9]  M. Owner-Petersen,et al.  Future large ground-based telescopes , 1999, IMTC/99. Proceedings of the 16th IEEE Instrumentation and Measurement Technology Conference (Cat. No.99CH36309).

[10]  G. Hill.  Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) , 2005 .

[11]  Andreas Kelz,et al.  Development of the wide-field IFU PPak , 2004, SPIE Astronomical Telescopes + Instrumentation.

[12]  Povilas Palunas,et al.  The Hobby-Eberly Telescope Completion Project , 2003, SPIE Astronomical Telescopes + Instrumentation.

[13]  S. Noll,et al.  The evolution of the luminosity functions in the FORS deep field from low to high redshift. II. The red bands , 2004 .

[14]  B. Schlesinger,et al.  Definition of the Flexible Image Transport System (FITS) , 2001 .

[15]  E. Greisen,et al.  Representations of celestial coordinates in FITS , 2002, astro-ph/0207413.

[16]  C. Goessl,et al.  Image reduction pipeline for the detection of variable sources in highly crowded fields , 2001, astro-ph/0110704.

[17]  Aniruddha R. Thakar,et al.  The Third Data Release of the Sloan Digital Sky Survey , 2004 .

[18]  J. A. Smith,et al.  SDSS data management and photometric quality assessment , 2004 .

[19]  J. D. Ponz,et al.  The FITS image extension , 1994 .

[20]  E. W. Greisen,et al.  Representations of spectral coordinates in FITS , 2005 .

[21]  S. Noll,et al.  The FORS Deep Field Spectroscopic Survey , 2004, astro-ph/0401500.

[22]  Napp,et al.  SDSS data management and photometric quality assessment , 2008 .

[23]  Arlette Pécontal-Rousset,et al.  The Euro3D data format: A common FITS data format for integral field spectrographs , 2004 .

[24]  Mark R. Calabretta,et al.  Representations of world coordinates in FITS , 2002, astro-ph/0207407.

[25]  Povilas Palunas,et al.  VIRUS: a massively replicated IFU spectrograph for HET , 2004, SPIE Astronomical Telescopes + Instrumentation.

[26]  M. Fukugita,et al.  The Sloan Digital Sky Survey Photometric System , 1996 .