An environmental analysis of the Type Ib SN 2019yvr and the possible presence of an inflated binary companion

Abstract

SN 2019yvr is the second Type Ib supernova (SN) with a possible direct detection of its progenitor (system); however, the spectral energy distribution (SED) of the pre-explosion source appears much cooler and overluminous than an expected helium-star progenitor. Using Hubble Space Telescope (HST) images and MUSE integral-field-unit (IFU) spectroscopy, we find the SN environment contains three episodes of star formation; the low ejecta mass suggests the SN progenitor is most likely from the oldest population, corresponding to an initial mass of 10.4$^{+1.5}_{-1.3}$ M⊙. The pre-explosion SED can be reproduced by two components, one for the hot and compact SN progenitor and one for a cool and inflated yellow hypergiant (YHG) companion that dominates the brightness. Thus, SN 2019yvr could possibly be the first Type Ib/c SN for which the progenitor’s binary companion is directly detected on pre-explosion images. Both the low progenitor mass and the YHG companion suggest significant binary interaction during their evolution. Similar to SN 2014C, SN 2019yvr exhibits a metamorphosis from Type Ib to Type IIn, showing signatures of interaction with hydrogen-rich circumstellar material (CSM) at >150 days; our result supports enhanced pre-SN mass loss as an important process for hydrogen-poor stars at the lower-mass end of core-collapse SN progenitors.

The Properties of Fast Yellow Pulsating Supergiants: FYPS Point the Way to Missing Red Supergiants

“…We also note that a few SNe Ibc now have claimed progenitor detections: PTF13bvn (Ib, discussed above), as well as SN2019yvr (Ib; Kilpatrick et al 2021;Sun et al 2022), andSN2017ein (Ib;Van Dyk et al 2018). One SN Ibc, SN2013ge, even has a claimed companion star for the progenitor (Fox et al 2022).…”

“…One SN Ibc, SN2013ge, even has a claimed companion star for the progenitor (Fox et al 2022). While in the case of SN2019yvr, Kilpatrick et al (2021) place the progenitor in the region of Figure 5 containing FYPS, Sun et al (2022) perform detailed binary stellar evolution modeling and claim that the progenitor is a much lower luminosity object with a yellow hypergiant companion. Ultimately, more work (and more progenitors) are needed to understand how SN Ibc fit into the picture that we have outlined above, and so we refrain from including them in Figure 5.…”

The Candidate Progenitor Companion Star of the Type Ib/c SN 2013ge

“…This is a slower evolutionary phase and hence more likely and has been suggested for stars in binaries that have gained mass (e.g., Justham et al 2014). It is interesting to note that modeling of the preexplosion photometry of the Type Ib SN 2019yvr also suggests that the potential companion is not an MS star (Sun et al 2022).…”

“…The early spectra of SN 2013ge show no signs of CSM interaction, although one explanation for the unusual double peak may have been a small ejection <1 yr prior to the explosion (Drout et al 2016). While SNe Ib/c typically explode in a low-density environment formed by years of progenitor winds, some SNe Ib/c are known to exhibit earlytime CSM interaction (e.g., Hosseinzadeh et al 2017), and a growing number of late-time observations have revealed that some SNe Ib/c may encounter a preexisting shell years after the initial explosion (e.g., Milisavljevic et al 2012), including SN 2019yvr discussed above (Sun et al 2022).…”

“…The nature of some, if not all, of these sources is still ambiguous. In any case, no postexplosion detections of a binary companion exist yet for fully stripped SNe Ib/c, although preexplosion spectral energy distributions (SEDs) suggest the possible presence of a companion source in the case of SN Ib iPTF13bvn (Cao et al 2013;Eldridge & Maund 2016;Folatelli et al 2016) and SN Ib 2019yvr (Kilpatrick et al 2021;Sun et al 2022).…”