{"id":1037,"date":"2016-07-18T09:24:53","date_gmt":"2016-07-18T06:24:53","guid":{"rendered":"http:\/\/phsites.technion.ac.il\/soker\/?page_id=1037"},"modified":"2020-05-18T14:28:11","modified_gmt":"2020-05-18T11:28:11","slug":"ilot-club","status":"publish","type":"page","link":"https:\/\/phsites.technion.ac.il\/soker\/ilot-club\/","title":{"rendered":"ILOT Club"},"content":{"rendered":"\n

The ILOT Club<\/strong><\/span><\/p>\n\n\n\n

This page is devoted to Intermediate Luminosity Optical Transient (ILOTS). Most broadly, these are astrophysical stars or stellar systems that experience outbursts with a peak luminosity somewhere between the peak luminosity of novae and supernovae.  With my collaborators Romauld Tylenda and Amit Kashi we have developed theoretical understandings of some objects in this heterogeneous group of objects.  <\/p>\n\n\n\n

Amit Kashi and I have placed ILOT on the Energy-Time Diagram seen below. We argue that most of them are powered by gravitational energy of stellar merger or accretion in a binary system. <\/p>\n\n\n\n

\"etd\"<\/a><\/figure>\n\n\n\n

* <\/strong>Latest additions:  <\/strong><\/span><\/span><\/p>\n\n\n\n

September 2016:<\/span> ASSASN 15qi<\/span>. <\/strong>We (Kashi & Soker, submitted to MNRAS in September 2016, posted on arXiv<\/a>) constructed a scenario where the outburst of the young-stellar-object ASASSN-15qi is an intermediate luminosity optical transient (ILOT). In this scenario a sub-Jupiter young planet was tidally destructed on to a young main-sequence star. Unlike the case of the more energetic ILOT V838 Mon, the mass of the destroyed planet is too low to inflate a giant envelope, and hence the merger remnant stays hot. This ILOT possesses two interesting properties: (1) its luminosity and total energy are below those of novae, and (2) it is not as red as other ILOTs. <\/span><\/p>\n\n\n\n

May 2016: SN 2015bh<\/span><\/strong> (other names as used in the diagram: SNHunt 275 and PTF 13efv).<\/span> <\/span><\/strong><\/span>We mark its 2013 eruption (Ofek et al. 2016 arXiv:1605.02450: an LBV giant eruption)  & M31LRN 2015<\/span> (<\/strong>see point 7 below); both are discussed in Soker & Kashi 2016, posted on the arXiv May 24, 2016).  Also added NGC4490-OT2011<\/strong> (Smith, Andrews, Van Dyk, S.~D., et al.  2016, MNRAS, 458, 950).<\/span>  <\/span><\/p>\n\n\n\n

Names<\/u><\/strong><\/span><\/p>\n\n\n\n

There is much confusion on the names to the intermediate transient objects.  We use the following.<\/span><\/p>\n\n\n\n

ILRT<\/strong>: Intermediate-Luminous Red Transients.<\/strong><\/span> These are events resulting from evolved stars, such as asymptotic giant branch (AGB) stars and similar objects (e.g., RGB stars). Most likely a companion accretes mass and powers the eruption, e.g., NGC 300 OT. A similar process occurs in giant eruptions of luminous blue variables (LBVs).<\/span><\/p>\n\n\n\n

LBV giant eruptions or SN impostor<\/strong>. Giant eruptions of Luminous Blue Variables.<\/strong> <\/span> Examples include the 1837-1856 Great Eruption of Eta Carinae and the pre-explosion eruptions of SN 2009ip. ILRTs are the low mass cousins of LBV giant eruptions.<\/span><\/p>\n\n\n\n

LRN or RT: Luminous Red Novae, or<\/strong> Red Transients or Mergerbursts<\/u>.<\/strong><\/span> These are powered by a full merger of two stars. Examples: V838 Mon and V1309 Sco. Merger events of stars with sub-stellar objects are also included.  <\/span><\/p>\n\n\n\n

ILOT<\/u><\/strong>: Intermediate-Luminosity Optical Transients.<\/strong>  ILOT<\/strong><\/span> is the term for the combined groups of ILRT,<\/strong> <\/span>LRN<\/span> <\/strong>and LBV giant eruptions<\/span>. <\/strong>They share many common physical processes, in particular being powered by gravitational energy.<\/span><\/p>\n\n\n\n