By Josh Meyers
Nov 2, 2014 | Of Galaxies, Stars, and Rainbows
Oct 19, 2014 | Black Holes Eating Stars and Making Waves
By William E. East
One of the more graphic terms in black hole physics is "spaghettification." It refers to the way that strongly varying gravitational forces can distort a round object into a shape most familiar from your dinner plate. This is a fate that can befall a star that has the misfortune to wander too close to a massive black hole. In this post, I want to tell you about some recent work I have done using computer simulations to explore how such stars get pulled and squashed as they fall into black holes. This work was done partly in order to understand whether we might soon be able to observe such events, in a nascent field of astronomy based on measuring gravitational waves.
Sep 17, 2014 | Dark Concentration -- It Matters!
By Andrea Albert
In the hunt for dark matter, any information to help us narrow in on what to look for is key. Miguel Sánchez-Conde (KIPAC and Stockholm University) and Francisco Prada (IFT/UAM, Madrid) have just published a crucial clue, concerning the concentration of dark matter halos, which are self-gravitating accumulations of dark matter that host systems like galaxies and galaxy clusters. Their recent paper on “the flattening of the concentration-mass relation towards low halo masses and its implications for the annihilation signal boost” combines theoretical predictions with simulations to learn about Earth-mass to galaxy cluster-sized halos. “The point of the paper is to put together the theory and the [simulations],” says Sánchez-Conde.
Sep 11, 2014 | A Mad Ballerina Consumes Her Companion
By Mandeep S. S. Gill
Take a star that weighs about twice as much as our Sun, and compact it down to the size of a medium-sized city, to make a neutron star whose extreme mass warps the spacetime everywhere near it. Next, put a much smaller companion star in orbit around it at very close range, and let the system evolve: what happens now?
Aug 28, 2014 | Supermassive Black Holes under a Gravitational Microscope
By Mandeep S. S. Gill
Astronomers strongly suspect that supermassive black holes play critical roles in the evolution of galaxies, but the details are not yet known. The masses of these monsters, when compared with the masses of their host galaxies, provide an important clue - but how do you weigh a black hole more than half way across the universe? KIPAC scientist Yashar Hezaveh has a great idea—and it involves using the most powerful radio telescope we have coupled to some new gravitational lenses.
Apr 9, 2014 | How special is "3 sigma"?
why you should check if the dice are loaded
Written by Andrea Albert
I was searching for evidence of dark matter as my PhD thesis when I was a graduate student at The Ohio State University. While I was still developing my analysis, another team of researchers doing something similar thought there was a chance they had found this evidence of dark matter at the center of the Galaxy.
Feb 9, 2014 | KIPAC Open House 2014
The 2014 KIPAC Public Open House will take place Saturday, May 3, 5 to 10 p.m.
The open house will feature talks, 3D movies of the universe, a planetarium dome, stargazing, Ask an Astronomer and much more. Visitors will also enjoy free hotdogs, snacks and beverages, and a raffle drawing for a chance to win two tickets to the California Academy of Sciences or a telescope.
To sign up, please visit the eventbrite page.
Oct 10, 2013 | Bundles of Rays Raise Prospects for LSST
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.
Example of ray bundle modeling for LSST: Image size (red) and measures of ellipticity (blue and purple) as a function of focal plane fine positioning relative to mirrors (z), for a simulated star image falling halfway to the outer edge of the focal plane
Sep 12, 2013 | The Highest Energies in the Universe
After a century of study, researchers still struggle to understand the origin of cosmic rays, particles with extreme energies that fill the Universe and bombard the Earth from all directions... On Tuesday at KIPAC@10, we asked: Where Did That Come From? and spent the morning talking about particle acceleration in the Universe. Afterwards, Luigi Tibaldo talked to Angela Olinto (KICP) and Neil Gehrels (NASA Goddard)
Jan 1, 2013 | Astronomers Capture Cosmic Jet Firing Up
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.
Optical image of the region of the new jet, showing the localization of the jet with Swift's X-ray detection and the radio detection from long distance interferometry. Image courtesy of NASA.