1. OBSERVATIONS OF GALAXY IC342 IN NARROW BAND [SII] AND Hα FILTERS
ANDJELIC, M. M., ARBUTINA, B., UROSEVIC, D., DOBARDZIC, A., PAVLOVIC, M. Z.
1Department of Astronomy, Faculty of Mathematics, University of Belgrade, Serbia

3. Emission nebula detection in optical range
[SII]/Hα emission-line ratios
Shock-heated SNRs > 0.4
photoionized nebulae < 0.4
(Blair & Long 2004, Matonick & Fesen 1997)
Observations in red continuum, [SII] and Hα narrow band filters
Data reduction
Low fluxes – long exposures – tracking problems
Continuum subtraction from emission-line
Absolute calibration with non-standard narrow-band filters
IRAF and IRIS software
-ovde treba naglasiti zahtevnost posmatranja u uskim filterima
-kao i to sto trazimo izvore vrlo malog sjaja, na rubu mogucnosti teleskopa

4. IC342 galaxy – nearby galaxy
Aim – optical detection of supernova remnants and HII region candidates
IC342 galaxy – nearby galaxy
large spiral, almost face-on galaxy, app. diameter ~20’
near Galactic plane, b ≈ 10º
heavily obscured
by Galactic extinction
(A ~ 1.5mag)
the most distance
determinations are
between Mpc
-interesantno je da je ova galaksija vrlo slicna M81, i isto bi izgledala na nebu, samo da se ne nalazi toliko blizu Galaktickoj ravni

5. Previous observations
4 SNR candidates, detected in optical range (D’Odorico et al. 1980)
Numerous observations in radio and X range, a few SNR candidates (Hummel & Grave 1990, Kong 2003, Mak et al. 2011)
Numerous HII regions (Hodge & Kennicutt 1983)
Tooth nebula – ultra-luminous X-ray source with optical, shock-heated counterpart

6. ROZHEN Observations 27th & 28th of November 2011
Telescope characteristics
2 m Ritchey-Chrétien-Coudé teleskope at the National Astronomical
Observatory, Rozhen, Bulgaria
Focal lenght 16m
CCD camera: VersArray1300B, 1340x1300 px, scale 0” /px
Field of view 5’45”x 5’35”
Observations
27th & 28th of November 2011
Exposure time 15 minutes
3 exposures through each filter
Three fields of view
Narrow band filters characteristics
Filter name
λ0 [Å]
FWHM [Å]
Tmax [%] Hα
6572 32
86,7
[SII]
6719 33
83,3
Red continuum
6416 26 58

7. -trece polje je posmatrano u non-photometric uslovima, tj bila je slaba oblacnost

8. Results 13 SNR candidates
11 new SNR candidates
Tooth-nebula
SNR2 from D’Odorico et al. (1980)
Note: SNR3 from D’Odorico et al. (1980) is HII region candidate!!!
374 HII region candidates in two fields of view (5’x5’)
666 HII region candidates in entire IC 342 (20’x20’), only positions, without fluxes (Hodge & Kennicutt 1983)

9. Optical SNR candidates in IC 342 galaxy

10. FOV1 Hα image, continuum substracted

11. FOV2 Hα image, continuum substracted

12. Future prospects
Completing galactic and extragalactic SNR and HII region samples
∑ – D relations for SNRs and HII regions
Star formation rate …
Optical observations are convenient method for this purpose (1 - 2 m telescopes are enough for observations of nearby galaxies) – Rozen, Vidojevica, Antalia

13. Regards from the Belgrade ISM gang!!!!!

14. THANK YOU FOR YOUR ATTENTION!