In the series, "Where are they now?" we check in with KIPAC alumni: where they are now, how they've fared since their days exploring particle astrophysics and cosmology at the Institute, and how their KIPAC experiences have shaped their journeys.
Gamma-ray observations of the Universe by the Fermi Gamma-ray Space Telescope have enabled another astrophysical constraint on the properties of particle dark matter.
The Fermi Gamma-ray Space Telescope continues to bridge astronomy and particle physics.
Simulations of accretion flows around black holes, involving General Relativity and relativistic plasma physics, have led to a new model of how extreme particle acceleration is achieved in the hearts of galaxies, gamma-ray bursts, and elsewhere.
May 5, 2015 | One Flavor of Quasar Or Two?
A team of KIPAC astrophysicists has applied a rigorous statistical analysis to observations of quasars resulting in an interesting perspective.
An example of a bias arising from data truncation. In this plot of radio luminosity versus redshift (distance) for quasars detected by a survey, inherently faint objects can only be seen if they are close (low redshift).
May 5, 2015 | Does Galactic Dust Twirl and Shine?
The question of whether we receive microwave radiation from spinning dust grains in our Galaxy has been debated for 15 years. A collaboration including a KIPAC scientist has provided valuable data indicating that the answer is probably yes.
The ARCADE 2 instrument being launched on a high altitude balloon. Getting above the atmosphere is important in an absolute atrophysical microwave measurement.
Although the Fermi Gamma-ray Space Telescope is primarily a gamma-ray instrument, its most cited paper reports a measurement of the combined electron and positron cosmic-ray spectrum. Now a team, led by KIPAC researchers, has built on this result by using a novel technique to separate the cosmic-ray electrons and positrons and measure the spectrum of each component individually. The result will keep theorists busy thinking about pulsars and dark matter.
May 5, 2015 | Let the Sun Shine (In Gamma Rays) II
Unifying the astronomically near and far, the Fermi Gamma-ray Space Telescope has seen its first signature of cosmic rays interacting with the light from our Sun.
The left panel shows the LAT gamma rays per pixel from near the Sun and the right panel shows the same for another patch of sky. There is a clear large flux from the solar disk and a less dense but extended flux surrounding it.
Huge natural thermonuclear explosions, so called stellar novae, are observed in binary systems consisting of a dense compact white dwarf circling a star. The Fermi LAT has for the first time ever detected gamma-ray emission from such an event. This observation indicates particle acceleration in the shock wave produced by the nova explosion to at least GeV energies.
May 5, 2015 | Simulating Stimulating Bursts of Gamma Rays
Using powerful computer simulations, a KIPAC scientist explores the possible mechanisms behind the gamma-ray emission in the super explosions known as gamma-ray bursts.
Artist's conception of a GRB. We see the burst of gamma rays if the jets are oriented so that one points toward us. (Image courtesy of NASA)
May 5, 2015 | Cutting-Edge Physics Computing Is No Game
Ever resourceful, physicists, including several KIPAC scientists, have been using the specialized processors in computer graphics display cards to speed up some of the calculations that arise in data analysis. In the coming era of large astronomical surveys for weak lensing constraints on dark energy, such speed will be essential.
Among the successes of the Fermi Gamma-ray Space Telescope is its discovery of the gamma-ray emission from many pulsars, the fascinating beacons in space. Additionally, KIPAC scientists have also used what Fermi has not seen from some pulsars to learn more about them.
May 5, 2015 | Hard X-rays Reveal Powerful Objects Near and Far
Creating the first ever catalog of the entire Galactic plane in hard x-rays, a KIPAC scientist has paved the way for a deeper understanding of the most luminous compact objects in our Galaxy, and of the x-ray emission from other galaxies.
Map of catalogued hard x-ray emitters in the Galactic center region with their significance in signal to noise