IAP 2015

Searching for Gravitational Waves with LIGO

Dr. Adam Libson, 2:00 - 2:30pm in 37-252

Einstein's theory of general relativity predicts the existence of gravitational radiation. Since gravity is a weak force, it takes extreme masses and energies to produce a detectable gravitational wave signature. Indirect evidence for the existence of this radiation has been collected using pulsar measurements. The Laser Interferometer Gravitational-Wave Observatory (LIGO) is an experiment designed to directly detect this radiation, and use it to study exotic astrophysical phenomena. To do this, LIGO must measure length changes with a precision of 10-19 meters, less than a thousandth of a proton diameter. In this talk, I will briefly discuss gravitational radiation and its sources, and I will also describe the LIGO detectors and the physics involved in their operation. Finally, I will discuss some of the quantum limits on making this type of precision measurement, and the ways in which LIGO hopes to beat these limits.

No enrollment limit for talk, no advance sign-up required.

Tour of the Laser Interferometer Gravitational Wave Observatory (LIGO) Lab

Dr. Adam Libson, 2:30 - 4:00pm departing from 37-252

Visitors will be taken on a tour of the LIGO prototyping facilities at MIT. These include a full-scale prototype of the LIGO vacuum chambers, laser, isolation and suspension systems, and laboratories for thermal and optical noise measurements.

Please Note:
10 people max for tour. Advance sign-up required, starting at 1:55pm immediately before Dr. Libson's talk in 37-252. Attendance of talk is required for tour of LIGO lab. Tour will leave from 37-252 at 2:30pm, and last until about 4:00pm.

Stellar Archaeology: New Science with Old Stars

Prof. Anna Frebel, 2:00 - 2:30pm in 37-252

The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the oldest Galactic stars are relics from the high-redshift Universe, they probe the chemical and dynamical conditions of a time when large galaxies first began to assemble. Through analysis of their surface composition, they probe the chemical and dynamical conditions as the Milky Way began to form, the origin and evolution of the elements, and the physics of nucleosynthesis. Some of these stars display a strong overabundance of the heaviest elements, in particular uranium and thorium. They can thus be radioactively dated, giving formation times ~ 13 Gyr ago, similar to the ~ 13.7 Gyr age of the Universe. In addition to talking about the science results, I will show a few video clips about observing with the 6.5m optical Magellan telescopes in the Atacama Desert in Chile.

No enrollment limit, no advance sign up.

Gravitational Mirages

Prof. Paul Schechter, 2:30 - 3:00pm in 37-252

According to Einstein's theory, gravity produces what is, in effect, an index of refraction. Light passing in the vicinity of an astronomical object will be delayed, deflected and distorted by the variations in this index of refraction, in a manner exactly analogous to terrestrial mirages. Such cosmic mirages are a major tool for the study of dark matter in galaxies and clusters of galaxies.

No enrollment limit, no advance sign up.

The First Stars

Mr. Alexander Ji, 2:00 - 2:30 pm in 37-252

The very first stars to form in the universe are fundamentally different from all subsequent generations of stars. Want to find out why? Come listen to this talk!

No enrollment limit, no advance sign up.

Seeing the Formation of the Universe with Radio Eyes

Mr. Abraham Neben, 2:30 - 3:00 pm in 37-252

Radio astronomy has been a crucial probe of the early universe since the discovery of the Cosmic Microwave Background in 1964. But most of the first billion years, during which the modern universe emerged out of a nearly homogenous soup of hydrogen, has remained hidden. I’ll discuss a new generation of radio telescopes just beginning to reveal the first stars and galaxies which are thought to have re-ionized the neutral hydrogen left over from the Big Bang. Using the Murchison Widefield Array in the remote Australian desert, we have begun to sift through Petabytes of data for hints of this theoretical Epoch of Reionization.

No enrollment limit, no advance sign up.

Creating an Apple Pie from Scratch: A Universe in a Supercomputer

Dr. Brendan Griffen, 2:00 - 2:30pm in 37-252

Describing the evolution of the Universe from the Big Bang to what we see today is not an easy undertaking. The advent of powerful parallel computers has created a unique opportunity for astronomers to study the build up of structure over cosmic time. In particular, these machines are now helping us understand when and how galaxies formed. Current models have remarkable success at reproducing the large scale features of our Universe, for example. Although a great deal of our modern understanding of the Universe has come from studying it in this way, current models are still struggling with the details, particularly on small scales. In my talk I will discuss the current state of the art in computational astrophysics, some of the problems in the models and how astronomers are working hard to solve them.

No enrollment limit, no advance sign up.

High-resolution x-ray optics at the Space Nanotechnology Laboratory: From nanometers to gigaparsecs

Ralf Heilmann, 2:30 - 3:15pm in 37-252

The Space Nanotechnology Laboratory (SNL) develops advanced lithography and nano-fabrication technology for high performance space instrumentation, as well as nanometer-accuracy metrology and assembly technology. Two current efforts are the development of nanofabricated soft x-ray gratings, the so-called critical-angle transmission (CAT) gratings, and the development of high-precision focusing X-ray mirrors. CAT gratings require the fabrication of sub-micron structures with extreme geometries and sub-nanometer precision, while x-ray mirrors are formed at 600 deg C while floating on porous air bearings. These efforts are aimed at instruments that can help find the missing baryons in the Cosmic Web and reveal the secrets of dark matter.

No enrollment limit, no advance sign up.

Tour of the Space Nanotechnology Lab

Ralf Heilmann, 3:15 - 4:15pm departing from 37-252

During the tour of the SNL's three clean rooms visitors will see sophisticated optical (interference lithography stations for the fabrication of submicron period gratings, high power UV laser, metrology station for optics shape measurements, sub-nanometer resolution interferometers, etc.), reactive-ion etching (Plasmtherm RIE, new STPS Pegasus DRIE) and mechanical systems (XY-air-bearing stage, environmental enclosure, active vibration isolation, etc.) as well as a scanning electron microscope, all of which support the development of thin-foil x-ray optics and gratings.

Please note:
6 people max for tour. Advance sign-up required starting at 2:25pm in 37-252 immediately before Dr. Heilmann's talk. Attendance of talk is required for tour of the Space Nanotechnology Lab. Tour will leave from 37-252 at 3:15pm, and last until about 4:15pm.

Observing Black Holes

Dr. Victoria Grinberg, 2:00 - 2:30pm in 37-252

Black holes are perhaps the most mind-boggling objects ever conceived by physicists and there is hardly any science fiction series today that will not feature them in some capacity. However, black holes are also very much observable and one of the major topics of today's X-ray astronomy.

No enrollment limit, no advance sign up. Space is limited for the X-ray Polarimetry Lab tour, and priority will be given to those who attend the talks in this session.

Using X-ray Spectroscopy to Measure a Binary's Relativistic Outflow

Dr. Herman Marshall, 2:30 - 3:00pm in 37-252

The stellar binary SS 433 was once featured on Saturday Night Live as the "comin' and a-goin' star". By means that are still somewhat mysterious, the system ejects blobs of plasma in opposite directions at a speed of about a quarter of the speed of light. The compact object that is responsible for providing the impetus for this plasma is probably a black hole about 10 times the mass of the Sun. I show what we've come to understand about the system and its jets such as how their directions trace out twin cones on the sky. X-ray spectroscopy, using the Chandra High Energy Transmission Grating Spectrometer that were built here at MIT, shows that the plasma temperature reaches at least 100 million degrees and can be used to measure the density and location of the outflows we call jets.

No enrollment limit, no advance sign up. Space is limited for the X-ray Polarimetry Lab tour, and priority will be given to those who attend the talks in this session.

An Introduction to the Chandra X-ray Observatory + Tour of the X-ray Polarimetry Lab

Dr. Michael Nowak and Dr. Norbert Schulz, 3:00 - 4:00pm in NE-83

Start with a brief introduction to the space-based Chandra X-ray Observatory, which MIT scientists helped build. Then, tour the X-ray Polarimetry Lab, where new X-ray instrumentation is currently being developed.

This event is in building NE-83. We will walk over as a group from building 37, immediately following Dr. Marshall's talk. NE-83 is about an 8 minute walk away, near the Cambridge Brewing Company.

Please note:
Building NE-83 is a restricted area. Advance sign up is required for the tour, starting at 1:55pm in 37-252. Guests are strongly encouraged to attend Dr. Grinberg's and Dr. Marshall's talks before tour. Tour is limited to 20 people, and priority will be given to those who attend the talks.

Exploring the Universe from Near to Far with the Chandra X-ray Observatory

Dr. Michael Nowak 2:30 - 3:00pm in 37-252

In the summer of 1999, NASA launched the third of its great observatories -- the Chandra X-ray telescope. Like the Hubble Space telescope which preceded it, Chandra is designed to have an unprecedented ability to create images and spectra of astrophysical objects, except working with high energy X-rays instead of optical light. This means that Chandra views some of the universe's most exotic and energetic phenomena: supernovae, neutron stars, black holes, jets traveling at nearly the speed of light emanating from near the center of clusters of galaxies. In this talk, we'll take a tour of the discoveries made by the Chandra X-ray telescope, starting with studies of our own solar system, moving outward to nearby stars, to the center of our own Galaxy where a black hole 40 millions times the mass of our Sun lurks, to distant clusters of Galaxies where the most massive black holes, billions of times the mass of our Sun, reside.

No enrollment limit, no advance sign up. Space is limited for the Chandra Operations Control Center tour, and priority will be given to those who attend this talk. The tour will depart immediately following this talk, and involve a short walk.

Tour of the Operations Control Center for the Chandra Space Telescope, One of NASA's Great Observatories

Dr. Norbert Schulz 3:00 - 4:15pm departing from 37-252

The Chandra X-ray Observatory is the world's most powerful X-ray telescope, allowing scientists to study the origin, structure and evolution of our universe in greater detail than ever before. The spacecraft and science instruments are controlled from the Operations Control Center (OCC) in Cambridge, Massachusetts. We will take our visitors on a tour of the OCC and show where scientists and engineers direct the flight and execute the observing plan of Chandra, and where they receive the scientific data from the observatory. during the tour the visitors will learn about the basics of X-ray astronomy and about the latest, exciting discoveries made by MIT scientists with data acquired with Chandra.

Please note: Advance sign-up *by e-mail* required for tour. Contact Debbie Meinbresse (meinbres@mit.edu) by 11:59pm on 1/22/2015 with attendees' names and citizenship information. Tour is limited to a maximum of 20 people. Priority will be given to those who attend Dr. Nowak's talk. The tour will depart immediately following this talk, and involve a short walk.

Fast X-ray Detectors for NICER: Astrophysics of Neutron Stars and Black Holes from the International Space Station

Dr. Ronald Remillard 2:00 - 2:30pm in 37-252

The NICER team at the MIT Kavli Institute for Astrophysics will deliver detectors that are a key portion of the 56-camera Instrument for X-ray astronomy that will be deployed on the International Space Station in 2016. The project is known as the Neutron star Interior Composition ExploreR ("NICER"). The cameras are sensitive to 0.2-12 keV photons, and each event will be time-tagged with instrument clock ticks that run at 40 ns. This talk will review the science goals, the instrument technology, and the calibration equipment that will help us to accomplish the goal to time-tag every event to the Solar system barycenter, to an accuracy of 100 ns.

No enrollment limit, no advance sign up.

Exoplanets with TESS: Alien Worlds in our Backyard

Dr. Zach Berta-Thompson 2:30 - 3:00pm in 37-252

MIT is building a new satellite to search the entire sky for exoplanets, planets orbiting other stars. Set to launch in 2017, the Transiting Exoplanet Survey Satellite (TESS) aims to find the best exoplanet targets for detailed characterization with upcoming big telescopes like the 6.5m James Webb Space Telescope or the 25-meter Giant Magellan Telescope. TESS will help astronomers understand what planets are made of, explore their atmospheres, and potentially (if we're really lucky) start to search for alien life beyond our Solar System. Come hear about this exciting MIT-led satellite mission!

No enrollment limit, no advance sign up.

Hunting Dark Matter

Mr. Adam Anderson 2:00 - 2:30pm in 37-252

Understanding the composition and properties of the matter in the universe is one of the most basic goals of physics, yet we know scandalously little about most of the matter. A concordance of diverse evidence from astrophysics and cosmology suggests that 85% of the matter in the universe is "dark": it is non-electromagnetically interacting and fundamentally different than the familiar matter of atoms that we experience in our day-to-day life. Though the existence and astrophysical properties of dark matter are established, its particle properties are unknown. I will describe the different pieces of evidence that have led to our current understanding of dark matter, culminating in the state-of-the-art direct searches that are probing its particle properties.

No enrollment limit, no advance sign up.

The Illustris simulation: Evolving the Universe on a Supercomputer

Dr. Federico Marinacci 2:30 - 3:00pm in 37-252

Numerical simulations are a fundamental tool in Theoretical Astrophysics to understand how the objects that populate our Universe formed and evolved. In this talk I am going to present the results of the Illustris simulation, one of the largest cosmological simulations ever performed, that follows the evolution of the Universe from the Big Bang to the present day. In particular, I will give a brief illustration of our current view on how galaxies are formed and what are the most important processes that shape their evolution.

No enrollment limit, no advance sign up.