اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدNebular spectroscopy of SN 2014J: Detection of stable nickel in near infrared spectra
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We present near infrared (NIR) spectroscopy of the nearby supernova 2014J obtained $sim$450 d after explosion. We detect the [Ni II] 1.939 $mu$m line in the spectra indicating the presence of stable $^{58}$Ni in the ejecta. The stable nickel is not centrally concentrated but rather distributed as the iron. The spectra are dominated by forbidden [Fe II] and [Co II] lines. We use lines, in the NIR spectra, arising from the same upper energy levels to place constraints on the extinction from host galaxy dust. We find that that our data are in agreement with the high $A_V$ and low $R_V$ found in earlier studies from data near maximum light. Using a $^{56}$Ni mass prior from near maximum light $gamma$-ray observations, we find $sim$0.05 M$_odot$ of stable nickel to be present in the ejecta. We find that the iron group features are redshifted from the host galaxy rest frame by $sim$600 km s$^{-1}$.
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As the closest Type Ia supernova in decades, SN 2014J provides a unique opportunity for detailed investigation into observational signatures of the progenitor system and explosion mechanism in addition to burning product distribution. We present a la
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We present near infrared (NIR) spectroscopic and photometric observations of the nearby Type Ia SN 2014J. The seventeen NIR spectra span epochs from +15.3 to +92.5 days after $B$-band maximum light, while the $JHK_s$ photometry include epochs from $-
$10 to +71 days. This data is used to constrain the progenitor system of SN 2014J utilizing the Pa$beta$ line, following recent suggestions that this phase period and the NIR in particular are excellent for constraining the amount of swept up hydrogen-rich material associated with a non-degenerate companion star. We find no evidence for Pa$beta$ emission lines in our post-maximum spectra, with a rough hydrogen mass limit of $lesssim$0.1 $M_{odot}$, which is consistent with previous limits in SN 2014J from late-time optical spectra of the H$alpha$ line. Nonetheless, the growing dataset of high-quality NIR spectra holds the promise of very useful hydrogen constraints.
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