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Poznań Astronomical Observatory Adam Mickiewicz University Poznań, Poland. Radial-velocity observations of pulsating stars with a new Poznań Spectroscopic Telescope. 23 June 2008. Our team R. Baranowski, P. Bartczak, W. Borczyk, W. Dimitrov, M. Fagas, K. Kamiński, T. Kwiatkowski, - PowerPoint PPT Presentation
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Radial-velocity observations of pulsating stars with a new
Poznań Spectroscopic Telescope
23 June 2008
Poznań Astronomical ObservatoryAdam Mickiewicz University
Poznań, Poland
Our team
R. Baranowski, P. Bartczak, W. Borczyk, W. Dimitrov, M. Fagas, K. Kamiński, T. Kwiatkowski, R. Ratajczak, A. Rożek, A. Schwarzenberg-Czerny
The „dome”
Mirors diameter – 0.4 m
Focal length – 1.8 m
Optical system – Newtonian
Diameter of the fibers – 50 m
Accesible altitudes h>24°
Mean. slewing rate 90°/min
Guiding cameras ST7
The telescope
The echellé spectrograph
Baudrand and Bohm (1992)
CCD camera:Andor DZ 4365-stage peltier cooling Temp. –95°C2048 x 2048 pix
pixel size 13.5 x 13.5μmdark current <1el/hreadout noise 2.1 el/pix
Echellé spectrograph
Spectral range:
4480 Å – 9250 Å
Resolution:
R=35000 (~8 km/s)
Acquisition box
Echellé spectrum – 64 orders
4480 Å – 9250 Å
blue range: 1pix = 0.04 Å order length = 80 Å every order adds 40 Å
middle: 1pix = 0.05 Å ~2.5 km/s order length = 100 Å every order adds 80 Å
red range: 1pix = 0.08 Å order length = 160 Å every order adds 125 Å
ThAr calibration spectrum
1400 lines
Flatfield and fringe effect
Flatfield and fringe effect
Telluric lines removal
Flux calibration
Line profiles
Sp=B1
V=1m
exp=250s
Hβ 4861 Å
Limiting magnitude - BD+39 3012C 11m.2 Sp=F5 exp=30min
28 And
δ Sct
Sp=A7III
V=5m.2
exp=600s
analysed by T. Kwiatkowski, W. Borczyk & A. Rożek
γ Peg
β Cep
Sp=B2IV
V=2m.8
exp=600sor 300s
period=3.4h
υ1=6.59 c/d
analysed by W. Borczyk
V440 Per
δ Cep
Sp=F7Ib
V=6m.3
exp=600s
analysed by A.Schwarzenberg-Czerny and M. Fagas
σpoz=136 m/s---2 harmonics---1 harmonic
Polaris
analysed by M. Fagas and K. Kamiński
okres obs. P [d] 2K [km/s] ref.
1896 – 1950 ~5-6Campbell (1899),Roemer (1965)
1899 - 1923 3.96809 Moore (1924)
1944 – 1954 3.96961 Stebbius (1946)
1981 – 1982 3.971562 ± 1
2.8 ± 0.6Arellano Ferro (1983)Kamper et al. (1984)
1987 - 1988 3.9746 ± 0.0008 1.5 ± 0.08 Dinshaw et al. (1989)
1992.41993.2
3.97268 ± 0.00011
1.555 ± 0.0561.517 ± 0.047
Hatzes & Cochran (2000)
1994.261996.96
3.97211.66 ± 0.021.68 ± 0.08
Kamper & Fernie (1998)
2005.1832006.3602007.349
3.97208 ± 0.00013
2.210 ± 0.0482.080 ± 0.0422.406 ± 0.018
Lee et al. (2008)
20083.97792 ±
0.00152.52 ± 0.03 Borowiec (2008)
Statistics
13 august 2007 - 30 may 2008
• 83 nights• 637 hours• 1080 science spectra
Colaborators
• Warsaw CAMK• Vienna Institute of Astronomy• Wrocław Astronomical Institute• Toruń Centre for Astronomy
Future perspectives
Upgrade of the telescope:
• 2 x 0.5m mirrors• simultaneous exposure of two fibers• better automatisation and remote control
Upgrade of the calibration, some ideas:
• experiment - mixing the ThAr and stellar light• Vrad accuracy increase with a iodine cell• spectral resolution increase with the EDI
interferometer
Radial velocity measurements:
• broadening function• TODCOR• spectral disentangling