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تسجيل مستخدم جديدPhotometric and Spectroscopic study of a highly reddened type Ia supernova SN 2003hx in NGC 2076
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تأليف
Kuntal Misra
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We present $UBVRI$ CCD photometry and optical spectra of the type Ia supernova SN 2003hx which appeared in the galaxy NGC 2076, obtained till $sim$ 146 days after the epoch of $B$ band maximum. The supernova reached at maximum brightness in $B$ band on JD 245 2893 $pm$ 1.0 with an apparent magnitude of 14.92 $pm$ 0.01 mag which was estimated by making template fits to the light curves. SN 2003hx is an example of a highly reddened supernova with $E(B-V)$ = 0.56 $pm$ 0.23. We estimate $R_v$ = 1.97 $pm$ 0.54 which indicates the small size of dust particles as compared to their galactic counterparts. The luminosity decline rate is $Delta m_{15}(B)$ = 1.17 $pm$ 0.12 mag and the absolute $B$ band magnitude obtained from the luminosity versus decline rate relation (Phillips et al. 1999) is $M^B_{max}$ = -19.20 $pm$ 0.18 mag. The peak bolometric luminosity indicates that $sim$ 0.66 $M_odot$ mass of $^{56}$ Ni was ejected by the supernova. The spectral evolution indicates the supernova to be a normal type Ia event.
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