Robert C. Duncan | |
---|---|
Born | Pensacola, Florida, U.S. | September 2, 1955
Academic background | |
Education | Dartmouth College (AB) Cambridge University (CPGS) Cornell University (PhD) |
Academic work | |
Discipline | Astrophysics |
Institutions | Princeton University University of Texas at Austin |
Robert C. Duncan (Jr.) (born September 2,1955) is an American astrophysicist now retired from the University of Texas at Austin.
Duncan was born in Pensacola,Florida,in 1955. He grew up in Houston and Boston,where his father played a key role in NASA's Apollo Project. [1] Duncan (Jr.) later earned a Bachelor of Arts degree in physics from Dartmouth College in 1977 and a PhD in physics from Cornell University in 1986. He also studied at the University of Cambridge. [2] As a student,Duncan was a competitive runner [3] [4] and marathoner. [5]
From 1986 to 1988,Duncan worked as a postdoctoral researcher at Princeton University. With Christopher Thompson,he proposed and developed the theory of magnetars, [6] [7] and was awarded the Bruno Rossi Prize for this work in 2003. [8] Duncan has written scientific research papers about neutron stars,supernovae,intergalactic gas clouds,neutrino emissions of very dense matter,MHD dynamos and related topics. [9]
A neutron star is the collapsed core of a massive supergiant star. It results from the supernova explosion of a massive star—combined with gravitational collapse—that compresses the core past white dwarf star density to that of atomic nuclei. Surpassed only by black holes,neutron stars are the second smallest and densest known class of stellar objects. They have a radius on the order of 10 kilometers (6 mi) and a mass of about 1.4 M☉. Stars that collapse into neutron stars have a total mass of between 10 and 25 solar masses (M☉),or possibly more for those that are especially rich in elements heavier than hydrogen and helium.
A magnetar is a type of neutron star with an extremely powerful magnetic field (~109 to 1011 T,~1013 to 1015 G). The magnetic-field decay powers the emission of high-energy electromagnetic radiation,particularly X-rays and gamma rays.
A soft gamma repeater (SGR) is an astronomical object which emits large bursts of gamma-rays and X-rays at irregular intervals. It is conjectured that they are a type of magnetar or,alternatively,neutron stars with fossil disks around them.
Kip Stephen Thorne is an American theoretical physicist and writer known for his contributions in gravitational physics and astrophysics. Along with Rainer Weiss and Barry C. Barish,he was awarded the 2017 Nobel Prize in Physics for his contributions to the LIGO detector and the observation of gravitational waves.
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,James Keeler,said,astrophysics "seeks to ascertain the nature of the heavenly bodies,rather than their positions or motions in space–what they are,rather than where they are",which is studied in celestial mechanics.
A pulsar is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Earth,and is responsible for the pulsed appearance of emission. Neutron stars are very dense and have short,regular rotational periods. This produces a very precise interval between pulses that ranges from milliseconds to seconds for an individual pulsar. Pulsars are one of the candidates for the source of ultra-high-energy cosmic rays.
Anomalous X-ray pulsars (AXPs) are an observational manifestation of magnetars—young,isolated,highly magnetized neutron stars. These energetic X-ray pulsars are characterized by slow rotation periods of ~2–12 seconds and large magnetic fields of ~1013–1015 gauss (1 to 100 gigateslas). As of 2017,there were 12 confirmed and 2 candidate AXPs known. The identification of AXPs with magnetars was motivated by their similarity to soft gamma repeaters.
The Bruno Rossi Prize is awarded annually by the High Energy Astrophysics division of the American Astronomical Society "for a significant contribution to High Energy Astrophysics,with particular emphasis on recent,original work". Named after astrophysicist Bruno Rossi,the prize is awarded with a certificate and a gift of USD $500,and was first awarded in 1985 to William R. Forman and Christine Jones Forman "for pioneering work in the study of X-ray emission from early type galaxies". It has been awarded 40 times. In 2010,the prize was awarded to William B. Atwood,Peter Michelson and the Fermi Gamma-ray Space Telescope team "for enabling,through the development of the Large Area Telescope,new insights into neutron stars,supernova remnants,cosmic rays,binary systems,active galactic nuclei,and gamma-ray bursts". In 2013,the prize was awarded to Roger W. Romani of Leland Stanford Junior University and Alice Harding of Goddard Space Flight Center for their work in developing the theoretical framework underpinning the many exciting pulsar results from Fermi Gamma-ray Space Telescope.
Frank Curtis "Curt" Michel was an American astrophysicist;a professor of astrophysics at Rice University in Houston,Texas;a United States Air Force pilot;and a NASA astronaut.
Peter Goldreich is an American astrophysicist whose research focuses on celestial mechanics,planetary rings,helioseismology and neutron stars. He is the Lee DuBridge Professor of Astrophysics and Planetary Physics at California Institute of Technology. Since 2005 he has also been a professor at the Institute for Advanced Study in Princeton,New Jersey. Asteroid 3805 Goldreich is named after him.
Andrew Christopher Fabian is a British astronomer and astrophysicist. He was Director of the Institute of Astronomy,University of Cambridge from 2013 to 2018. He was a Royal Society Research Professor at the Institute of Astronomy,Cambridge from 1982 to 2013,and Vice-Master of Darwin College,Cambridge from 1997 to 2012. He served as president of the Royal Astronomical Society from May 2008 through to 2010.
HakkıBoran Ögelman was a Turkish physicist and astrophysicist. He was an expert on gamma ray astronomy,the physics of neutron stars,and solar energy and worked on several key topics in modern astrophysics. He made many contributions to high energy astrophysics. In his early professional career he engaged in the SAS-II Small Gamma Ray Astronomy Satellite experiment development,data analysis,and first detection and imaging of our universe in gamma rays with his NASA colleagues,as well as in other fields of physics. His main interests in the field of astrophysics were the study of gamma ray astronomy and compact objects such as neutron stars and pulsars. Ögelman worked at NASA Goddard Space Flight Center,Middle East Technical University (METU) in Ankara,Turkey,Çukurova University in Adana,Turkey,Max Planck Institute (MPI) at Garching,Germany and the University of Wisconsin.
Robert J. Nemiroff is an Astrophysicist and Professor of Physics at Michigan Technological University. He received his Ph.D. from the University of Pennsylvania in Astronomy and Astrophysics in 1987 and his B.S. from Lehigh University in Engineering Physics in 1982. He is an active researcher with interests that include gamma-ray bursts,gravitational lensing,and cosmology,and is the cofounder and coeditor of Astronomy Picture of the Day (APOD),the home page of which receives over a million hits a day,approximately 20% of nasa.gov traffic. He is married and has one daughter.
Fiona A. Harrison is the Kent and Joyce Kresa Leadership Chair of the Division of Physics,Mathematics and Astronomy at Caltech,Harold A. Rosen Professor of Physics at Caltech and the Principal Investigator for NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission. She won the Hans A. Bethe Prize in 2020 for her work on NuSTAR.
Dr. Martin C. Weisskopf until his retirement from NASA in at the end of May,2022,was project scientist for NASA's Chandra X-ray Observatory and Chief Scientist for X-ray Astronomy in the Space Sciences Department at NASA's Marshall Space Flight Center in Huntsville,Alabama. He was also the Principal Investigator of the Small Explorer mission the Imaging X-ray Polarization Explorer (IXPE).
Chryssa Kouveliotou is a Greek astrophysicist. She is a professor at George Washington University and a retired senior technologist in high-energy astrophysics at NASA's Marshall Space Flight Center in Huntsville,Alabama.
Alice Kust Harding is an American astrophysicist at the NASA Goddard Space Flight Center,Greenbelt,Maryland.
Samar Safi-Harb is a professor in the Department of Physics and Astronomy at the University of Manitoba and a Canada Research Chair in Supernova Remnant Astrophysics and Extreme Astrophysics. She was the Vice President of the Canadian Astronomical Society from 2020 to 2021.
James Wellington Truran Jr. was an American physicist,known for his research in nuclear astrophysics.
Christopher Thompson is a Canadian astronomer and astrophysicist. He is a professor of astronomy at the University of Toronto Canadian Institute for Theoretical Astrophysics (CITA).
{{cite book}}
: |journal=
ignored (help)