Research Highlights

Oct 15, 2017 | An event that blew away the astronomical world

On the morn of Thursday, August 17, 2017 the LIGO-Virgo Collaboration (LVC) gravitational wave detectors saw a binary neutron star (BNS) collision in gravitational waves—and kind of blew up the astronomical world who was in on it, that day.

Why do I say this, after the announcement of the discovery of gravitational waves from a binary black hole (BBH) coalescence already made such major "ripples" amongst those who pay attention to things astronomical, just 1 1/2 years ago? (Resulting in the Nobel Prize being awarded for this, on October 3, 2017).

Sep 21, 2017 | Probing the planet formation environment

As an astronomer, I think I live in a spectacularly exciting time to be studying the process of planet formation. Little needs to be said about how dramatically the Kepler satellite telescope and other exoplanet surveys have revolutionized our understanding of the exoplanet population, as these kinds of discoveries pop up in the news on a seemingly daily basis. We now know that the planet formation process produces a diverse set of final products, many of which (such as hot Jupiters and super Earths) look very different from the planets in our own solar system.

Sep 4, 2017 | DES clinches the most precise cosmological results ever extracted from gravitational lensing

For decades, cosmologists have been attempting to piece together the history and composition of the Universe. Since we now know that ~95% of the Universe’s mass-energy content takes the form of invisible dark matter and dark energy, this is a very difficult task indeed. However, with such enormous catalogs of galaxies such as those produced by the Dark Energy Survey (DES), we can use what we observe about the visible matter in the Universe (in the form of stars and galaxies) to infer the behavior of dark matter and dark energy.

Sep 3, 2017 | KIPAC reacts: Members' stories from the path of totality

Now, to bring it a little closer to home from our general astronomical discussion of eclipses (see the previous blog post), let's check in with some KIPAC folks who actually were in the eclipse's zone of totality and see what their reactions were to the actual event.

Sep 3, 2017 | When our life-giving local star disappears!

The Great American Eclipse of 2017 occurred on August 21 in a slightly less than 100-mile-wide strip. It entered the US off the northern Oregon coast and exited off the coast of South Carolina about two hours later (see, for example, here for a clickable path map)—and several KIPAC members made sure to station themselves within this strip, also known as the "Zone of Totality," hoping to experience firsthand this very rare life event (on any given place on the Earth, total eclipses occur only about every 100 years, though they occur somewhere on the Earth about every year and a half).

Aug 16, 2017 | On the trail of dark matter with LUX-ZEPLIN

Based on a press release from the SLAC Office of Communications

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory, including several KIPAC scientists, are on a quest to solve one of physics’ biggest mysteries: What exactly is dark matter—the invisible substance that accounts for 85 percent of all the matter in the universe but can’t be seen even with our most advanced scientific instruments?

Aug 4, 2017 | Standard model of the universe withstands most precise test by Dark Energy Survey

Astrophysicists have a fairly accurate understanding of how the Universe ages: That’s the conclusion of new results from the Dark Energy Survey (DES), a large international science collaboration, including researchers from the Department of Energy’s SLAC National Accelerator Laboratory, that put models of cosmic structure formation and evolution to the most precise test yet.

Jul 5, 2017 | The first galaxies could really mix it up!

An international team of researchers, most of whom have ties to KIPAC, has shown that the hot diffuse gas that fills the space between the galaxies has the same concentration of iron in all galaxy clusters that were studied in sufficient detail by the Japanese Suzaku satellite.

An international team of researchers, most of whom have ties to KIPAC, has shown that the hot diffuse gas that fills the space between the galaxies has the same concentration of iron in all galaxy clusters that were studied in sufficient detail by the Japanese Suzaku satellite.

These results confirm the team's earlier findings regarding the Perseus Cluster, published in Nature, which suggested that most of the iron in the Universe was produced and spread throughout intergalactic space before galaxy clusters formed, more than 10 billion years ago. The iron, along with many other elements, was blown out of galaxies by the combined energy of billions of supernovae, as well as outbursts from growing supermassive black holes.

Jun 16, 2017 | Gigantic X-rays flares offer new insight into the whirling maelstrom just outside supermassive black holes

Supermassive black holes power some of the most luminous objects we see in the Universe. When material spirals into a supermassive black hole in the center of a galaxy that is in excess of a million Solar masses, it gives rise to an active galactic nucleus, or AGN (also discussed in two previous KIPAC blogposts: this one focused on observations of flaring from AGNs, whilethis one focused on simulation aspects). In addition to spewing electromagnetic radiation running from visible light through ultraviolet all the way to X-rays and gamma rays, many AGN can launch jets of particles at close to the speed of light. These jets are detected through the radio waves they emit by synchrotron radiation and can extend between 50 and 100 kpc (about 150,000 to 300,000 light years) from the central black hole. All this activity occurs in and around the so-called accretion disc: the flattened disc of gas that is spiralling into the black hole, just moments before it plunges through the surface of no return, the “event horizon” of the central massive black hole.

May 3, 2017 | They blinded it for science

Scientific introspection is necessary because of a known unknown in the world of experimentation called experimenter bias, the name given to all the ways in which simply being human can affect how scientists take data, analyze data, and interpret data. “Experimenter bias” is a known—i.e. it is well-known to exist—but it’s also unknown, because the psychology of the human scientist can’t be easily quantified. Researchers can’t add error bars indicating the strength of a preconceived notion or the weight of an unconscious desire, yet subtle and not-so-subtle influences definitely exist, such as the result of a previous experiment or the conclusion of a popular theory, and these influences can nudge a researcher into accepting a result prematurely or discounting results that don’t conform to expectation.

Apr 6, 2017 | SPT-3G deployment: Going to the ends of the Earth to capture pictures of the infant universe

Last December, I travelled to the southernmost tip of the Earth to install a new camera on the South Pole Telescope (following a rich tradition of other KIPAC researchers who have travelled to Antarctica and returned to write about it, e.g. Val Monticue and Albert Wandui). This blogpost brings you along for a bit of that journey!

Mar 8, 2017 | Seeing is believing: “Observing” simulations of relativistic jets

The high-energy universe is a fascinating place to observe: giant stars explode into supernovae, briefly outshining their own galaxies; pulsars with more mass than our Sun but only twelve miles across spin hundreds of times each second; and supermassive black holes at the centers of galaxies can suck dust and gas into accretion disks and blast this material in plasma form back out in powerful relativistic jets spewed out at close to the speed of light.