Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userType IIb Supernova 2013df Entering Into An Interaction Phase: A Link between the Progenitor and the Mass Loss
124
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We report the late-time evolution of Type IIb Supernova (SN IIb) 2013df. SN 2013df showed a dramatic change in its spectral features at ~1 year after the explosion. Early on it showed typical characteristics shared by SNe IIb/Ib/Ic dominated by metal emission lines, while later on it was dominated by broad and flat-topped Halpha and He I emissions. The late-time spectra are strikingly similar to SN IIb 1993J, which is the only previous example clearly showing the same transition. This late-time evolution is fully explained by a change in the energy input from the $^{56}$Co decay to the interaction between the SN ejecta and dense circumstellar matter (CSM). The mass loss rate is derived to be ~(5.4 +- 3.2) x 10^{-5} Msun/yr (for the wind velocity of ~20 km/s), similar to SN 1993J but larger than SN IIb 2011dh by an order of magnitude. The striking similarity between SNe 2013df and 1993J in the (candidate) progenitors and the CSM environments, and the contrast in these natures to SN 2011dh, infer that there is a link between the natures of the progenitor and the mass loss: SNe IIb with a more extended progenitor have experienced a much stronger mass loss in the final centuries toward the explosion. It might indicate that SNe IIb from a more extended progenitor are the explosions during a strong binary interaction phase, while those from a less extended progenitor have a delay between the strong binary interaction and the explosion.
rate research
Read More
We have obtained early-time photometry and spectroscopy of Supernova (SN) 2013df in NGC 4414. The SN is clearly of Type IIb, with notable similarities to SN 1993J. From its luminosity at secondary maximum light, it appears that less $^{56}$Ni ($lesssim 0.06 M_{odot}$) was synthesized in the SN 2013df explosion than was the case for the SNe IIb 1993J, 2008ax, and 2011dh. Based on a comparison of the light curves, the SN 2013df progenitor must have been more extended in radius prior to explosion than the progenitor of SN 1993J. The total extinction for SN 2013df is estimated to be $A_V=0.30$ mag. The metallicity at the SN location is likely to be solar. We have conducted Hubble Space Telescope (HST) Target of Opportunity observations of the SN with the Wide Field Camera 3, and from a precise comparison of these new observations to archival HST observations of the host galaxy obtained 14 years prior to explosion, we have identified the progenitor of SN 2013df to be a yellow supergiant, somewhat hotter than a red supergiant progenitor for a normal Type II-Plateau SN. From its observed spectral energy distribution, assuming that the light is dominated by one star, the progenitor had effective temperature $T_{rm eff} = 4250 pm 100$ K and a bolometric luminosity $L_{rm bol}=10^{4.94 pm 0.06} L_{odot}$. This leads to an effective radius $R_{rm eff} = 545 pm 65 R_{odot}$. The star likely had an initial mass in the range of 13 to 17 $M_{odot}$; however, if it was a member of an interacting binary system, detailed modeling of the system is required to estimate this mass more accurately. The progenitor star of SN 2013df appears to have been relatively similar to the progenitor of SN 1993J.
Type IIb Supernova (SN) 2011dh, with conclusive detection of an unprecedented Yellow Supergiant (YSG) progenitor, provides an excellent opportunity to deepen our understanding on the massive star evolution in the final centuries toward the SN explosion. In this paper, we report on detection and analyses of thermal X-ray emission from SN IIb 2011dh at ~500 days after the explosion on Chandra archival data, providing a solidly derived mass loss rate of an YSG progenitor for the first time. We find that the circumstellar media (CSM) should be dense, more than that expected from a Wolf-Rayet (WR) star by one order of magnitude. The emission is powered by a reverse shock penetrating into an outer envelope, fully consistent with the YSG progenitor but not with a WR progenitor. The density distribution at the outermost ejecta is much steeper than that expected from a compact WR star, and this finding must be taken into account in modeling the early UV/optical emission from SNe IIb. The derived mass loss rate is 3 x 10^{-6} Msun/year for the mass loss velocity of ~20 km/s in the final ~1,300 years before the explosion. The derived mass loss properties are largely consistent with the standard wind mass loss expected for a giant star. This is not sufficient to be a main driver to expel nearly all the hydrogen envelope. Therefore, the binary interaction, with a huge mass transfer having taken place at >1,300 years before the explosion, is a likely scenario to produce the YSG progenitor.
We report the first detection of a credible progenitor system for a Type Ic supernova (SN Ic), SN 2017ein. We present spectra and photometry of the SN, finding it to be similar to carbon-rich, low-luminosity SNe Ic. Using a post-explosion Keck adaptive optics image, we precisely determine the position of SN 2017ein in pre-explosion hst images, finding a single source coincident with the SN position. This source is marginally extended, and is consistent with being a stellar cluster. However, under the assumption that the emission of this source is dominated by a single point source, we perform point-spread function photometry, and correcting for line-of-sight reddening, we find it to have $M_{rm F555W} = -7.5pm0.2$ mag and $m_{rm F555W}-m_{rm F814W}$=$-0.67pm0.14$ mag. This source is bluer than the main sequence and brighter than almost all Wolf-Rayet stars, however it is similar to some WC+O- and B-star binary systems. Under the assumption that the source is dominated by a single star, we find that it had an initial mass of $55substack{+20-15} M_{odot}$. We also examined binary star models to look for systems that match the overall photometry of the pre-explosion source and found that the best-fitting model is a $80$+$48 M_{odot}$ close binary system in which the $80 M_{odot}$ star is stripped and explodes as a lower mass star. Late-time photometry after the SN has faded will be necessary to cleanly separate the progenitor star emission from the additional coincident emission.
We investigate ZTF18aalrxas, a double-peaked Type IIb core-collapse supernova (SN) discovered during science validation of the Zwicky Transient Facility (ZTF). ZTF18aalrxas was discovered while the optical emission was still rising towards the initial cooling peak (0.7 mag over 2 days). Our observations consist of multi-band (UV, optical) light-curves, and optical spectra spanning from $approx0.7$ d to $approx180$ d past the explosion. We use a Monte-Carlo based non-local thermodynamic equilibrium (NLTE) model, that simultanously reproduces both the $rm ^{56}Ni$ powered bolometric light curve and our nebular spectrum. This model is used to constrain the synthesized radioactive nickel mass (0.17 $mathrm{M}_{odot}$) and the total ejecta mass (1.7 $mathrm{M}_{odot}$) of the SN. The cooling emission is modeled using semi-analytical extended envelope models to constrain the progenitor radius ($790-1050$ $mathrm{R}_{odot}$) at the time of explosion. Our nebular spectrum shows signs of interaction with a dense circumstellar medium (CSM), and this spetrum is modeled and analysed to constrain the amount of ejected oxygen ($0.3-0.5$ $mathrm{M}_{odot}$) and the total hydrogen mass ($approx0.15$ $mathrm{M}_{odot}$) in the envelope of the progenitor. The oxygen mass of ZTF18aalrxas is consistent with a low ($12-13$ $mathrm{M}_{odot}$) Zero Age Main Sequence mass progenitor. The light curves and spectra of ZTF18aalrxas are not consistent with massive single star SN Type IIb progenitor models. The presence of an extended hydrogen envelope of low mass, the presence of a dense CSM, the derived ejecta mass, and the late-time oxygen emission can all be explained in a binary model scenario.
We have identified a progenitor candidate in archival Hubble Space Telescope (HST) images for the Type Ic SN 2017ein in NGC 3938, pinpointing the candidates location via HST Target-of-Opportunity imaging of the SN itself. This would be the first identification of a stellar-like object as a progenitor candidate for any Type Ic supernova to date. We also present observations of SN 2017ein during the first ~49 days since explosion. We find that SN 2017ein most resembles the well-studied Type Ic SN 2007gr. We infer that SN 2017ein experienced a total visual extinction of A_V~1.0--1.9 mag, predominantly because of dust within the host galaxy. Although the distance is not well known, if this object is the progenitor, it was likely of high initial mass, ~47--48 M_sun if a single star, or ~60--80 M_sun if in a binary system. However, we also find that the progenitor candidate could be a very blue and young compact cluster, further implying a very massive (>65 M_sun) progenitor. Furthermore, the actual progenitor might not be associated with the candidate at all and could be far less massive. From the immediate stellar environment, we find possible evidence for three different populations; if the SN progenitor was a member of the youngest population, this would be consistent with an initial mass of ~57 M_sun. After it has faded, the SN should be reobserved at high spatial resolution and sensitivity, to determine whether the candidate is indeed the progenitor.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
