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The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope. Tanyu Bonev Institute of Astronomy Bulgarian Academy of Sciences. Optical and mechanical design Modes of observations with examples Conclusions.
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The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope Tanyu Bonev Institute of Astronomy Bulgarian Academy of Sciences • Optical and mechanical design • Modes of observations with examples • Conclusions
16 m Focal length 5.6 m f/8 f ratio f/2.8 0.31 arcsec/px Scale (1 px = 0.024 mm) 0.88 arcsec/px
FoReRo2: Modes of Observations • Broad band imaging • Narrow band imaging • Long slit spectroscopy • Fabry-Perot imaging • Imaging polarimetry
FoReRo2: Broad band imaging and photometry Available Filters: U, B, V, R, I Example: Landolt field PG1633+099, filter V, Exposure = 15 sec
FoReRo2: long slit spectrography Grating prisms (grisms) Blue ChannelRed Channel 600 lines/mm300 lines/mm 0.3 nm/px0.5 nm/px Long slit: Length: covers the full FOV Width: 110 microns = 1.5 arcsec
FoReRo2: long slit spectrography Blue ChannelRed Channel < 445 nm> 490 nm
FoReRo2: low dispersion spectra Blue ChannelRed Channel < 445 nm> 490 nm
FoReRo2: Fabry-Perot Imaging interferogram of [OI] 6300 in comet Q4 (NEAT), obtained on May 23, 2004. Interference filter + 500 micron Fabry-Perot etalon in the red channel. Exposure: 600 sec [OI] 6300 night sky emission
FoReRo2: Imaging polarimetry mode Comet Q4 (NEAT) Optical arrangement 90o +45o -45o 0o
FoReRo2: Narrow band imaging Part of the available interference filters
Narrow band imaging of comet Q4 (NEAT) On-line, 616 nm, H2O+ Off-line, 642 nm, Continuum - k *
Comet Q4 (NEAT), May 26, 2004 H2O+ ions in the near nucleus region
Comet Q4 (NEAT), May 26, 2004 Dynamics of the H2O+ ions in the near nucleus region 11 frames x 300 sec exposure Total time of the sequence < 1 h
FoReRo2: Conclusions • The 2-channel focal reducer increases the power of the 2-meter telescope by: • Changing the f ratio from f/8 to f/2.8 • Allowing simultaneous data acquisition in two spectral ranges • The 2-channel focal reducer offers several modes of observations: • Broad band imaging • Narrow band imaging • Long slit spectroscopy • Fabry-Perot imaging • Imaging polarimetry