1 / 16

NGC 2506 – a try for a spectroscopic study

NGC 2506 – a try for a spectroscopic study. Ekaterina Atanasova Petr Kabath Christine Oppegaard Mª Carmen Sánchez Gil Tutor: Frédéric Royer. 2nd NEON Archive Summer School 2006. Open clusters – Why are they so interesting?. The members are all at about the same distance

charis
Download Presentation

NGC 2506 – a try for a spectroscopic study

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. NGC 2506 – a try for a spectroscopic study Ekaterina Atanasova Petr Kabath Christine Oppegaard Mª Carmen Sánchez Gil Tutor: Frédéric Royer 2nd NEON Archive Summer School 2006

  2. Open clusters – Why are they so interesting? • The members • are all at about the same distance • have approximately the same age • have about the same chemical composition • have different masses Probes for stellar evolution theories

  3. NGC 2506 Right Ascension (2000) : 08 00 01 Declination (2000) : -10 46 12 Galactic longitude : 230.564 Galactic latitude : 9.935 Distance [pc] : 3460 Reddening [mag] : 0.081 Distance modulus [mag] : 12.95 Log Age : 9.045 Metallicity : -0.37 Data from http://www.univie.ac.at/webda/ Open Cluster NGC 2506 Aladin image

  4. Spectroscopic data VLT data was obtained from the ESO Archive • 2004-01-15 Royer/Gomez • 2004-01-17 Royer/Gomez • 2004-02-14 Pallavicini et al • 2005-03-28 Grundahl et. al. • 8 scientific frames The spectra were taken using Giraffe spectrograph mounted on VLT 2 KUYEN Why Giraffe?

  5. FLAMES Instrument • Mounted on KUEYEN • Access to targets over 25' in diam. Spectrographs: • GIRAFFE R=25000 or 10000 - up to 130 targets • UVES Rmax=47000 - only 8 targets

  6. Giraffe - Spectrograph R = 7500 - 30000 Spectral region 370 – 900 nm 2K X 4K EEV CCD (15 µm pix.) Modes: • MEDUSA – 2 modes • IFU • ARGUS ARGUS: 22 times 14 1) 0.52“/microlens 2) 0.3“/microlens IFU: 20 microlenses 0.52“

  7. Possible to observe 132 objects • Resolution: each fiber equals to 1.2“ of the sky • 2 Slits - High resolution • - Low resolution • High resolution mode (HR) - 22 filters • (379 nm to 920.5 nm) • Low resolution mode (LR) - 8 filters • (385.7 nm to 881.7 nm) MEDUSA fibers (Image by ESO) MEDUSA Modes

  8. Giraffe data pipeline 3 flat fields 5 bias frames master flat field Wavelength calibration file master bias Scientific image Scientific image calibrated

  9. Calibration of a scientific frame 1 Raw bias Raw flat Master bias Master flat

  10. Calibration of a scientific frame 2 • Output = (Sci-bias)/(Master flat) • Wavelength calibration with Th-Ar Lamp Some comments • No need of dark subtraction • No flux calibration • No sky subtraction Dispersion axis Cross dispersion axis

  11. Calibrated spectra 2004-02-14

  12. Cross identification of our targets with photometric data 34 objects identified (B-V)marconi=0.032143+0.90548*(B-V)pallavicini Marconi et al., Old open clusters UBGVRI photometry of NGC 2506, MNRAS., 3 June 2006

  13. Science? 2004-02-14 Pallavicini et al. 2004-01-15 Royer/Gomez 2005-03-28 Grundahl et al. Marconi et al.

  14. Radial velocity distribution in the field =2.25206 Mean=82.8379 

  15. To be or not to be …. A member?

  16. Still a lot of work to do….but THANK YOU FOR YOUR ATTENTION:-) Jean FranÇois Petr Christine Carmen Katia

More Related