1. Astronomical Observation part II. Spectometry 2009.10.14 Jubee Sohn 010.9126.2606 jbsohn@astro.snu.ac.kr

2. Plan Class : Mon – Prof. / Wed – practice Assitant : Jubee Sohn / 19-214 10/14 : Instrumentation 10/21 : Visit Observatory + start observation 10/28 : Preprocessing 11/04 : Analysis

3. Instrumentation Telescope - 24 inch - Rich-Cretian Optics - F/7 - Control : TCS ( same as SNU 0bs.1 )

4. Instrumentation CCD ( ST8 - XME) - Imaging array : 1530 x 1020 - Pixel size : 9 μm - CCD size : 13.8 x 9.2 mm - Readout Noise : 15e- - gain : 2.3 e- Note : 관측 1 시간 전 냉각.

6. Instrumentation Spectrometer - Santa Babara Self Guided Spectrograph (SB SGC) (http://www.sbig.com/pdffiles/sgs_manual3.pdf) - LED Switch : LED ON/OFF Grating Toggle : High / Low Micrometer Screw : Central wavelength control Focus Achromat : Focus for spectrograph

7. Character of SB SGC Gratings Slit - Wide width ( proper galaxy obs.) : 72μm - Narrow width ( proper star obs. ) : 18μm Resolution - Narrow slit & high : 2.4 Å - Narrow slit & low : 10 Å - Wide slit & high : 10 Å - Wide slit & low : 38 Å Wavelength rage : 3800 - 7500Å Low resolutionHigh resolution 150 lines /mm600 lines/mm 4.3Å/pix1.05Å/pix

8. Character of SB SGC Connect the CCD & Computer Run CCDOPS Tracking mode for Spectrograph Focus mode for CCDOPS Turn on the LED switch to get light Adjust slit focus Locate the slit at the center of tracking CCD

9. Observation Setup the CCDOPS parameters (check the Temp. ) Focusing - Setup : Tracking CCD - Focus : type proper exp. time - Move to the bright object - Adjust the focus with focusing screw

10. Observation(cont.) Get the target on the slit

11. Observation(cont.) Using cover switch, intercept the light to the tracking CCD Setup Imaging CCD Press the Grab and start exposure After the observation, turn of the CCD after the warm up

12. Observation(cont.) Bias ( 10 images before & after, respectively ) Dark ( 3 ~ 5 images for each exp.time ) Flat image Comparing source - Before & After the target exposure - Continuum, Ne, He Targets Preprocessing Analaysis : wavelength calibration flux caligbration

13. Expeted result SB SGS + ST8 Be star HD 217050 V=5.4mag Exp : 900s High resolution Center : 5750Å

14. Note! Be careful to use every facillity & instrument Report when any problems happen! After the observation, please clean up the observatory Keep quiet when you do observation ( ∵ CEOU)

15. Preparing Proposal! Which object will you observe? - Planet ( Jupiter, Saturn, Venus ) - Star ( Type – O ~ M / giant ~ dwarf ) - galaxy ( Spiral / Elliptical ) - Quasar Why do we observe those targets? - Spectral characteristic

16. Preparing Proposal! http://www.sbig.com/sbwhtmls/online.htm Ex ) Stellar Spectra

17. Preparing Proposal!

18. References - SIMBAD ( Basic astronomical object info. ) http://simbad.u-strasbg.fr/simbad/http://simbad.u-strasbg.fr/simbad/ - Messier Catalog ( Various bright object catalog ) http://messier.obspm.fr/http://messier.obspm.fr/ - DSS ( Useful site to make Finding chart) http://archive.stsci.edu/cgi-bin/dss_formhttp://archive.stsci.edu/cgi-bin/dss_form

19. Other notice Learn how to use IRAF ( basic things ) How to use IDL Reading assignment - SB SGC manual (http://www.sbig.com/sbwhtmls/online.htm) - ST8 manual (http://www.sbig.com/sbwhtmls/online.htm) Using notice board on ‘ 개설 교과목 ’