Noam Soker
   HOME

TheInfoList



OR:

Noam Soker is an Israeli
theoretical astrophysicist Astrophysics is a science that employs the methods and principles of physics and chemistry in the study of astronomical objects and phenomena. As one of the founders of the discipline said, Astrophysics "seeks to ascertain the nature of the hea ...
. He was the chair of the physics department at the
Technion – Israel Institute of Technology The Technion – Israel Institute of Technology ( he, הטכניון – מכון טכנולוגי לישראל) is a public research university located in Haifa, Israel. Established in 1912 under the dominion of the Ottoman Empire, the Technion ...
from 2009 to 2015.


Biography and career

Soker was born in
Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...
in 1958. He spent his childhood in Kibutz Yas'ur. In 1975 he started his undergraduate studies in the department of mathematics and physics at the
University of Haifa The University of Haifa ( he, אוניברסיטת חיפה Arabic: جامعة حيفا) is a university located on Mount Carmel in Haifa, Israel. Founded in 1963, the University of Haifa received full academic accreditation in 1972, becoming Is ...
at Oranim, and completed them in 1982, in the Technion, after a three years break for service in the
Israel Defense Forces The Israel Defense Forces (IDF; he, צְבָא הַהֲגָנָה לְיִשְׂרָאֵל , ), alternatively referred to by the Hebrew-language acronym (), is the national military of the Israel, State of Israel. It consists of three servic ...
. Under the supervision of
Mario Livio Mario Livio (born June 19, 1945) is an Israeli-American astrophysicist and an author of works that popularize science and mathematics. For 24 years (1991-2015) he was an astrophysicist at the Space Telescope Science Institute, which operates th ...
and Oded Regev, Soker completed his Ph.D. dissertation, about Bondi–Hoyle–Lyttleton accretion in a non-homogeneous gas. Soker was a
postdoctoral researcher A postdoctoral fellow, postdoctoral researcher, or simply postdoc, is a person professionally conducting research after the completion of their doctoral studies (typically a PhD). The ultimate goal of a postdoctoral research position is to p ...
at the
University of Virginia The University of Virginia (UVA) is a Public university#United States, public research university in Charlottesville, Virginia. Founded in 1819 by Thomas Jefferson, the university is ranked among the top academic institutions in the United S ...
from 1986 to 1989, and continued for a second
post-doctoral degree A doctorate (from Latin ''docere'', "to teach"), doctor's degree (from Latin ''doctor'', "teacher"), or doctoral degree is an academic degree awarded by universities and some other educational institutions, derived from the ancient formalism ''li ...
at the Center for Astrophysics Harvard & Smithsonian (19891992). During that time he developed models for cooling flows in
galaxy cluster A galaxy cluster, or a cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by gravity, with typical masses ranging from 1014 to 1015 solar masses. They are the second-l ...
s, and started to work in the field of
planetary nebulae A planetary nebula (PN, plural PNe) is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives. The term "planetary nebula" is a misnomer because they are unrelated ...
. In 1992 Soker has received the Alon Fellowship and returned to Israel to become an assistant
professor Professor (commonly abbreviated as Prof.) is an Academy, academic rank at university, universities and other post-secondary education and research institutions in most countries. Literally, ''professor'' derives from Latin as a "person who pr ...
at the Mathematics-Physics Department of the
University of Haifa The University of Haifa ( he, אוניברסיטת חיפה Arabic: جامعة حيفا) is a university located on Mount Carmel in Haifa, Israel. Founded in 1963, the University of Haifa received full academic accreditation in 1972, becoming Is ...
at Oranim. He was promoted to associate professor in 1994, and to full professor in 1998. From 1994 to 1998 he served as the chairman of the Mathematics-Physics Department. In 2003 he moved to the Department of Physics at the Technion, and served as the chair of the physics department for six years (20092015). Soker is presently the dean of science in the Guangdong Technion-Israel Institute of Technology. He is also appointed as the head of the Center for Pre-University Studies at the Technion.


His Work

Soker studies a variety of astrophysical objects, with a common thread being the conservation of
angular momentum In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational analog of linear momentum. It is an important physical quantity because it is a conserved quantity—the total angular momentum of a closed syst ...
. For over 20 years Soker has been studying processes by which planets influence the late evolution of stars, such as the shaping of some planetary nebulae. He is known for his model of planetary nebulae formation as a result of
binary star A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...
interaction that results in disc accretion and the ejection of jets that shape the nebula into a bipolar form. In the field of cooling flows in clusters of galaxies, Soker developed a model that accounted for the observational problem that clusters are hotter than anticipated by theory. There was a lack of the large amount of cool gas predicted by models. Soker suggested a "cold feedback" scenario, where nonlinear over-dense blobs of gas cool quickly and are removed from the
intracluster medium In astronomy, the intracluster medium (ICM) is the superheated plasma that permeates a galaxy cluster. The gas consists mainly of ionized hydrogen and helium and accounts for most of the baryonic material in galaxy clusters. The ICM is heated to t ...
before the next major
active galactic nucleus An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much-higher-than-normal luminosity over at least some portion of the electromagnetic spectrum with characteristics indicating that the luminosity is not pr ...
heating event in their region. Soker also worked in the field of
common envelope In astronomy, a common envelope (CE) is gas that contains a binary star system. The gas does not rotate at the same rate as the embedded binary system. A system with such a configuration is said to be in a common envelope phase or undergoing commo ...
evolution in binary stars. He has developed the "core-degenerate" model to account for the explosion of
type Ia Supernova A Type Ia supernova (read: "type one-A") is a type of supernova that occurs in binary systems (two stars orbiting one another) in which one of the stars is a white dwarf. The other star can be anything from a giant star to an even smaller white ...
e, as a result of the merger of a white dwarf with the core of an
Asymptotic Giant Branch The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) lat ...
star in the late stages of common envelope. Soker developed a model for the nineteenth century great eruption of the LBV
Eta Carinae Eta Carinae (η Carinae, abbreviated to η Car), formerly known as Eta Argus, is a stellar system containing at least two stars with a combined luminosity greater than five million times that of the Sun, located around distant in t ...
. The model proposes that when the LBV erupted, its binary companion accreted gas and launched jets that formed the hourglass shaped Homunculus Nebula. In recent years Soker has studied Intermediate Luminosity Optical Transients (ILOTS), which are stellar eruptions with luminosity between a
nova A nova (plural novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", which is Latin for "new") that slowly fades over weeks or months. Causes of the dramati ...
and a
supernova A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
. One of the prototypes for such an event is
V838 Monocerotis V838 Monocerotis (Nova Monocerotis 2002) is a spectroscopic binary star system in the constellation Monoceros (constellation), Monoceros about 19,000 light years (6 parsec, kpc) from the Sun. The previously unremarked star was observed i ...
, that according to Soker's model, erupted as a merger of two
main-sequence In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hert ...
stars that underwent a merger process. Soker and his collaborators claim there is a strong connection between V838 Mon-like eruptions and
supernova impostor Supernova impostors are stellar explosions that appear at first to be a supernova but do not destroy their progenitor stars. As such, they are a class of extra-powerful novae. They are also known as Type V supernovae, Eta Carinae analogs, and gia ...
s.


References


External links


Google Scholar cites

Noam Soker's home page

The Intermediate-Luminosity Optical Transients page

A Scientific American review on Planetary Nebulae by Noam Soker
{{DEFAULTSORT:Soker, Noam Academic staff of Technion – Israel Institute of Technology 1958 births Living people Israeli astrophysicists Israeli astronomers Jewish physicists