the 2-channel focal reducer (forero2): a new observing facility for the 2-meter telescope
DESCRIPTION
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. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/1.jpg)
The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope
Tanyu Bonev
Institute of Astronomy
Bulgarian Academy of Sciences
1. Optical and mechanical design
2. Modes of observations with examples
3. Conclusions
![Page 2: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/2.jpg)
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
![Page 3: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/3.jpg)
![Page 4: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/4.jpg)
FoReRo2: Modes of Observations
1. Broad band imaging 2. Narrow band imaging 3. Long slit spectroscopy4. Fabry-Perot imaging5. Imaging polarimetry
![Page 5: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/5.jpg)
FoReRo2: Broad band imaging and photometry
Available Filters: U, B, V, R, I
Example: Landolt field PG1633+099, filter V, Exposure = 15 sec
![Page 6: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/6.jpg)
FoReRo2: long slit spectrography
Blue Channel Red Channel
600 lines/mm 300 lines/mm
0.3 nm/px 0.5 nm/px
Long slit:
Length: covers the full FOV
Width: 110 microns = 1.5 arcsec
Grating prisms (grisms)
![Page 7: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/7.jpg)
< 445 nm > 490 nm
FoReRo2: long slit spectrography
Blue Channel Red Channel
![Page 8: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/8.jpg)
FoReRo2: low dispersion spectra
< 445 nm > 490 nm
Blue Channel Red Channel
![Page 9: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/9.jpg)
FoReRo2: Fabry-Perot Imaging
Name Kind Useful
range
nm
Reference wavelength
nm
Free spectral range
mounted
Quensgate visual
tunable 410 - 700 627 5.8 Before beamsplitter
Quensgate blue
tunable 355 – 510 374.7 4.3 Before beamsplitter
CSIRO visual
Fixed airgap
410-700 620 0.21 Before beamsplitter
CSIRO red Fused silica
450-700 615 0.26 Red arm
CSIRO blue
Fused silica
350-530 400 0.17 Blue arm
![Page 10: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/10.jpg)
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
![Page 11: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/11.jpg)
FoReRo2: Imaging polarimetry mode
Comet Q4 (NEAT)Optical arrangement
+45o
0o
90o
-45o
![Page 12: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/12.jpg)
FoReRo2: Narrow band imaging
Part of the available interference filters
Blue channel Red channel
Filters for cometary observations
390 nm - CN 406 nm - C3 426 nm - CO+ 443 nm - Blue Continuum …
590 nm - Na
616 nm - H2O+
630 nm – [OI]
642 nm – Red
Continuum …
Filters of common
interest
[SIII] 3722
[SII] 4069, 4076
[OIII] 5007 …
[OI] - 6300
Halpha - 6563
[SII] 6716, 6731 …
![Page 13: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/13.jpg)
Narrow band imaging of comet Q4 (NEAT)
On-line, 616 nm, H2O+ Off-line, 642 nm, Continuum
- k *
![Page 14: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/14.jpg)
Comet Q4 (NEAT), May 26, 2004 H2O+ ions in the near nucleus region
![Page 15: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/15.jpg)
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
![Page 16: The 2-channel focal reducer (FoReRo2): a new observing facility for the 2-meter telescope](https://reader035.vdocuments.us/reader035/viewer/2022062722/568139c3550346895da16949/html5/thumbnails/16.jpg)
FoReRo2: Conclusions
• The 2-channel focal reducer increases the power of the 2-meter telescope by:
1. Changing the f ratio from f/8 to f/2.82. Allowing simultaneous data acquisition in two spectral
ranges
• The 2-channel focal reducer offers several modes of observations:
1. Broad band imaging2. Narrow band imaging3. Long slit spectroscopy4. Fabry-Perot imaging5. Imaging polarimetry