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تسجيل مستخدم جديدQuark-Novae in massive binaries : a model for double-humped, hydrogen-poor, superluminous Supernovae
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LSQ14bdq and SN 2006oz are super-luminous, hydrogen-poor, SNe with double-humped light curves. We show that a Quark-Nova (QN; explosive transition of the neutron star to a quark star) occurring in a massive binary, experiencing two Common Envelope (CE) phases, can quantitatively explain the light curves of LSQ14bdq and SN 2006oz. The more massive component (A) explodes first as a normal SN, yielding a Neutron Star which ejects the hydrogen envelope of the companion when the system enters its first CE phase. During the second CE phase, the NS spirals into and inflates the second He-rich CE. In the process it gains mass and triggers a Quark-Nova, outside of the CO core, leaving behind a Quark Star. The first hump in our model is the QN shock re-energizing the expanded He-rich CE. The QN occurs when the He-rich envelope is near maximum size (~ 1000R_sun) and imparts enough energy to unbind and eject the envelope. Subsequent merging of the Quark Star with the CO core of component B, driven by gravitational radiation, turns the Quark star to a Black Hole. The ensuing Black Hole accretion provides sufficient power for the second brighter and long lasting hump. Our model suggests a possible connection between SLSNe-I and type Ic-BL SNe which occur when the Quark Nova is triggered inside the CO core. We estimate the rate of QNe in massive binaries during the second CE phase to be ~ 5x10^(-5) of that of core-collapse SNe.
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A Quark-Nova (QN, the sudden transition from a neutron star into a quark star) which occurs in the second common envelope (CE) phase of a massive binary (Ouyed et al., 2015a&b), gives excellent fits to super-luminous, hydrogen-poor, Supernovae (SLSNe
) with double-peaked light curves including DES13S2cmm, SN 2006oz and LSQ14bdq (http://www.quarknova.ca/LCGallery.html). In our model, the H envelope of the less massive companion is ejected during the first CE phase while the QN occurs deep inside the second, He-rich, CE phase after the CE has expanded in size to a radius of a few tens to a few thousands solar radii, this yields the first peak in our model. The ensuing merging of the quark star with the CO core leads to black hole formation and accretion explaining the second long-lasting peak. We study a sample of 8 SLSNe Ic with double-humped light-curves. Our model provides good fits to all of these with a universal explosive energy of 2x10^52 erg (which is the kinetic energy of the QN ejecta) for the first hump. The late-time emissions seen in iPTF13ehe and LSQ14bdq are fit with a shock interaction between the outgoing He-rich (i.e second) CE and the previously ejected H-rich (i.e first) CE.
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