The CEJSN r-process scenario (October 2018) 

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In a new paper Aldana Grichener and I study r-process feasibility inside jets launched by a cold neutron star (NS) spiralling-in inside the core of a giant star, and find that such common envelope jets supernova (CEJSN) events might be a significant source of heavy r-process elements in the early Universe.  To account for the r-process abundances in the Galaxy we require that one in ten cases of a NS entering the envelope of a giant star ends as a CEJSN r-process event.

Live poster in the Shocking Supernovae meeting (June 2018)

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In the meeting  Shocking Supernovae (Stockholm May 28 – June 1, 2018)  I presented a live poster. I updated it every day, presenting my personal view on many talks and posters.  In the picture on the right I stand near my poster on jets, and my personal summary of the first day of the meeting.  

I gave the last talk of the meeting, where I also presented my personal summary of he meeting.  

The summary of the first 4 days can be found here.  The summary talk is here

 

 

Common Envelope Jets Supernova (November 2017)

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In a new paper Avishai Gilkis and I proposed a common envelope jets supernova scenario for the enigmatic supernova iPTF14hls where a neutron star that spirals-in inside the envelope of a massive giant star accretes mass and launches jets that power the ejection of the circumstellar shell and a few weeks later the explosion itself.

Live poster (July 2017)

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In the meeting The IMPACT of BINARIES on STELLAR EVOLUTION (ESO Garching, July 3-7, 2017), I presented a live poster. I updated it twice a day, referring to many talks and posters. 

Click on an image to enlarge it and you can read the poster on the far right. 

Core collapse supernova remnants with ears (November 2016)

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In a new paper Aldana Grichener and I study the morphologies of core collapse supernova remnantzfigcs (CCSNRs) and find that about third of CCSNRs have two opposite `ears’ protruding from their main shell, and that the typical energy that is required to inflate these ears is about 10 percents of the explosion kinetic energy. We argue that these properties are most compatible with the expectation from the explosion jet feedback mechanism (JFM). This study further supports the call for a paradigm shift from neutrino-driven to jet-driven core-collapse supernova mechanisms.

A popular summary of our research is in New Scientist.

Simulating the Grazing envelope evolution (July 2016)

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In a new paper Sagiv Shiber, Amit Kashi, and I, presented the first simulations of the grazing envelope evolution (GEE).  In the GEE jets launched by the secondary star efficiently remove the outer part of the giant envelope, while the secondary star grazes the surface of the primary giant star and spirals-in. 

Simulations: A secondary main sequence star enters the envelope of an asymptotic giant branch star of 3.4 solar mass. We assume that the secondary star launches two opposite jets perpendicular to the orbital plane.  There are three segments, each 1.5 years: (i) Density in the orbital plane; (ii) 3D image of jet material (blue) and ejected gas from the envelope of the giant primary star (red); (iii) Temperature in the equatorial plane.   GEE_ref6

The jet feedback mechanism (May 2016)

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I posted a review paper on the operation of jets in a negative feedback mechanism in stars, galaxies, and clusters of galaxies. I argue that jets are more common that what is usually thought, and that they play an important role in powering many different kind of astrophysical objects.  (paper posted to the arXiv.)