Archives 2011

Newly detailed computer simulations show how magnetic fields grew in the first stars, and may change our view of the Universe's original shiny objects.

The discovery of gamma-ray flares in the Crab Nebula was rated by Astronomy Magazine as the number two space story of 2011. Now KIPAC scientists report on another, larger, flaring episode, and are beginning to crack the mystery of why this source can be so variable.

Scientists from KIPAC and the SLAC theory department have demonstrated that astrophysical observations from the Fermi Gamma-ray space telescope can probe the validity of a class of famous particle physics theories known as supersymmetry.

By realistically simulating a population of gamma-ray bursts, KIPAC scientists have demonstrated the extent to which these explosions can be mischaracterized when they are far away.

An intriguing new model of the emission surrounding the Vela Pulsar may explain a famous mystery in high energy astrophysics.

Simulations based on our current understanding of dark matter predict a larger number of small dwarf satellite galaxies around our Milky Way than are observed. Now work by KIPAC scientists has shown that this discrepancy is more universal.

By assembling a large amount of optical data from galaxies which host supernova explosions, a KIPAC graduate student has shown that when it comes to supernovae, location matters.

A KIPAC professor and graduate student have used savvy astronomical detective work to piece together the identity of a previously enigmatic gamma-ray source. The object is a black widow pulsar which is destroying its companion star.

Photometric redshift determination is crucial to the success of dark energy missions such as LSST and DES. A KIPAC postdoc has developed an important tool for photometric redshift estimation and applied it to 60 million galaxies from the Sloan Digital Sky Survey.

Peering into the past, KIPAC scientists use Fermi gamma-ray telescope observations to unlock the story of blazar evolution over the history of the Universe.

KIPAC scientists, in collaboration with international colleagues, are developing a gamma-ray spectrometer for the ASTRO-H satellite, to open a new frontier for investigating the high energy Universe.

In order to properly design and construct LSST, and to effectively use its eventual data, scientists are devising sophisticated models to follow light through a complicated optical system that isn't yet built.

Fermi's Large Area Telescope has detected gamma-ray pulsations from a radio pulsar with one of the highest magnetic fields known. The object appears to be a missing link between standard pulsars and the more extreme magnetars.

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.

Using X-ray, radio, and gamma-ray observations of a distant galaxy, a multinational team of astrophysicists has seen perhaps the first live instance of the turning on of a powerful jet from a supermassive black hole.

By turning their gaze to small satellite galaxies where the total mass is most dominated by dark matter, astrophysicists using data from the Fermi Gamma-ray Space Telescope have achieved the tightest constraints on the properties of dark matter particles to date.

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.

Both instruments on the Fermi Gamma-ray Space Telescope have seen a gamma-ray burst also detected by other observatories, giving scientists a unique opportunity to learn more about these enigmatic blasts.

The origin of the extragalactic gamma-ray background remains a cosmic and high energy physics enigma as KIPAC scientists have estimated the contribution to it from blazars in two different ways.

In the KIPAC Visualization Lab - and in major planetariums - visitors can watch three dimensional movie renderings of processes from the history of the Universe. KIPAC scientists use novel computer graphics techniques to produce and display the animations, which are based on the results from computational simulations.

By the end of the decade, the Large Synoptic Survey Telescope (LSST) will begin gazing at the sky and revolutionizing the study of dark energy and astronomy. Today, however, scientists are already hard at work learning how to analyze LSST's unprecedented amount and complexity of data with the Image Simulator.

Active galactic nuclei reveal the presence of enormous amounts of matter interacting with a supermassive black hole at the center of a galaxy. Because galaxies merge over the history of the Universe, we should see the signatures of supermassive black holes merging in some places. An analysis of X-ray observations may have shown just that.

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.

Simulating the evolution of the early Universe on computers is the starting point for cosmologists' understanding of structure formation in the cosmos. With techniques to pursue both a large volume of simulated universe and high spatial resolution, KIPAC researchers are leading the charge against one of the foremost computational challenges in astrophysics.

Some of the highest energy physical processes in the Universe emit powerful gamma-rays that can be detected when they hit our atmosphere with a flash. A group of KIPAC scientists have developed a new electronics chip that can sample 16 different signals at a billion or more times per second, in order to follow the extreme show.

A KIPAC researcher uses images of very distant galaxies to learn about somewhat nearer galaxies, through the phenomenon of gravitational lensing.

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.

A new prediction of the density and velocity distribution of dark matter particles at our position in the Galaxy has provided a revised estimate of the likely detection rates for dark matter in particle physics experiments.

An analysis of X-ray observations has provided the clearest picture to date of the size, mass, and matter content of a giant cluster of galaxies. The study also provides the first direct evidence that the multi-million-degree gas in the cluster's outskirts is clumped into enormous clouds.

In a nice marriage of theory and experiment, KIPAC scientists have investigated the effects of small layers of contamination on optical surfaces, which is important in building the super telescope that will probe dark energy.

The Fermi Gamma-ray Space Telescope, famous for probing the Galaxy and distant reaches of the Universe, has now seen its first flare from our own Sun.

Data from the Fermi Gamma-ray Space Telescope has revealed a new gamma-ray binary, a rare class of object in which a gamma ray source is in orbit around a star.

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.

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.

KIPAC scientists have used Fermi Gamma-ray Space Telescope observations to detect a flare in a distant active galaxy, with it becoming temporarily the brightest gamma-ray source in the entire sky, and indicating the most luminous object, aside from gamma-ray bursts, discovered in the Universe to date.

KIPAC astrophysicists have used a technique that processes information in a way analogous to the human brain in order to determine whether galaxy shapes can help determine their place in the Universe.

A team of KIPAC astrophysicists has applied a rigorous statistical analysis to observations of quasars resulting in an interesting perspective.