Overall dust input from core-collapse supernovae in the Galaxy
Takaya Nozawa (takaya.nozawa@nao.ac.jp)
National Astronomical Observatory of Japan (NAOJ)○ Abstract

There are increasing pieces of evidence that core-collapse supernovae (CCSNe) are efficient producers of dust particles;
recent far-infrared observations as well as analyses of optical line emissions have revealed the presence of dust above 0.1 Msun in the ejecta ofyoung supernova remnants such as SN 1987A and Cassiopeia A. However, some fraction of these newly formed dust grains would finally bedestroyed by the passage of the reverse shocks (RSs). Furthermore, stripped-envelope CCSNe, which occupy half of the total number ofCCSNe, are likely to be poor suppliers of interstellar dust. Here, by taking account into these effects suppressing dust inputs from CCSNe,
we summarize the fundamental knowledge about the overall dust input (and relative contributions of dust masses) from asymptotic giant
branch (AGB) stars and CCSNe, based on an extremely simple dust evolution model.

○ Contributions of dust mass from stellar sources・ φ(m) = Am-α: Salpeter initial mass function (IMF) with α=2.35
normalization :where・ md, AGB (i=1): mass of dust injected per AGB star whose initial
mass is between m1 = 2 Msun and m2 = 8 Msun
・ md, SN (i=2): mass of dust injected per CCSN whose initial stellar
mass is between m2 = 8 Msun and m3 = mSN・ ψ(t): star formation rate

Table 1 – Relative numbers, In(mi, mi+1), of AGB stars and CCSNe for representative combinations of the lower masslimit (mlow) and upper mass limit (mup) of stars in the Salpeter IMF, which are derived from the equation below. The(cumulative) number ratios of CCSNe to AGB stars are about 0.17, independent of the stellar mass range of IMF.
Also is given the relative number of CCSNe in the case that the upper mass limit of the SNe is mSN = 18 Msun.

○ Dust yields per AGB star・ Case 1 (AGB1)fAGB = 0.01 and m_WD = 1.4 M sun
・ Case 2 (AGB2)(e.g., Dell’Agli et al. 2017)○ Dust yields per CCSNFig. 1 – (Left panel) Time evolutions of dust masses that are injected by AGBs stars and CCSNe for a constant starformation rate of ψ(t) = ψ0 = 10 Msun yr-1. The mass range of stars is set to be from mlow = 0.1 Msun to mup = 100 Msun.
Colored lines discriminate the results for different dust yields per AGB star and per CCSN (see left). (Right panel)Time evolutions of dust masses relative to the cumulative stellar mass Mstarin, which equals to (t ψ0). In both figures,dashed lines indicate the results in the case that the upper mass limit of CCSNe is mSN = 18 Msun, which isconsidered to be the maximum mass of SNe II-P (Smartt 2009).

・ Case 1 (SN1)fSN = 0.01 and m_NS = 2.0 M sun

・ Case 2 (SN2)(optimistic)(e.g., Matsuura et al. 2011; De Looze et al. 2017)
・ Case 3 (SN3)(after RSs)(e.g., Bocchio et al. 2016; Nozawa et al. 2007)
・ Case 4 (SN4)(pessimistic)(e.g., Kotak et al. 2009; Nozawa et al. 2010)
SNe II-P, likely major producers of dust, have the upper mass
limit of mSN = 18 M sun? (Smartt 2009) ➜ see dashed lines in figures

Fig. 2 – Time evolutions of the ratio of SN-dust mass to AGB-dust mass, corresponding to the results in Figure 1.
The left panel shows the results for different SN-dust yields relative to AGB1 (a higher dust yield from AGB stars),
while the right panel plots the results relative to AGB2 (a smaller dust yield from AGB stars). In both figures, dashedlines indicate the results in the case that the upper mass limit of CCSNe is mSN = 18 Msun.

○ Results and Conclusions
・ If condensation efficiency of dust in AGB winds and SN ejecta is the same (0.01 in this study),
the contributions of dust mass from AGB stars and CCSNe are comparable. (AGB1 and SN1)
・ If CCSNe can eject 0.5 Msun (0.01 Msun) of dust, the mass of interstellar dust that originatedfrom CCSNe is 3-20 times higher (lower) than that from AGB stars. (SN2 and SN3)・ If dust mass per CCSN is as low as 10 -4 Msun, the abundance of SN-dust is less than 1% ofAGB-dust, which seems consistent with the abundance of SN-dust in presolar grains. (SN4)・ Assuming the upper mass limit of CCSNe to be mSN = 18 Msun reduces the mass of SN-origin
dust by about a factor of 1.4.

References:
Bocchio, M., et al., 2016, A&A, 587, 157
Bevan, A., et al. 2016, MNRAS, 456, 1269
Bevan, A., et al. 2017, MNRAS, 465, 4044
Dell’Agli, F., 2017, MNRAS, accepted, arXiv:1702.03904
De Looze, I., et al. 2017, MNRAS, 465, 3309
Kotak, R., et al. 2009, ApJ, 704, 306
Matsuura, M., et al. 2011, Science, 333, 1258
Nozawa, T., et al. 2007, ApJ, 666, 955
Nozawa, T., et al. 2010, ApJ, 713, 356
Smartt, S. J., 2009, ARA&A, 47, 63