EHT 2014

Conference Date: 
Monday, November 10, 2014 (All day) to Friday, November 14, 2014 (All day)
Scientific Areas: 
Strong Gravity

 

The Event Horizon Telescope is the first astronomical instrument capable of imaging the horizon of a known black hole. By assembling a global network of existing millimetre and sub-millimetre wavelength observatories, the EHT can access the extraordinary resolutions required via Very Long Baseline Interferometry. Already it has detected horizon scale structure around the supermassive black holes at the centre of the Milky Way and the giant elliptical galaxy M87.

This is the second in a conference series designed to bring together the full EHT community, from instrument builders to theoretical modellers, for the purpose of fully exploiting the unique opportunities that the EHT provides. The goals of this conference will be: 

  • Describe the broad scientific context of astrophysical black holes and its relationship to EHT observations, including how the EHT can provide insight into systems ranging from pulsars to galaxy clusters by probing accretion and energetic outflows on the scale of the Schwarzschild radius. 
  • Discuss developments in our understanding of the astrophysics of the initial EHT
    targets: the supermassive black holes at the centre of the Milky Way (Sgr A*) and M87.
  • Present new EHT-driven results. 
  • Describe the current technical status and discuss the planned development of the EHT, including the imminent inclusion of the Atacama Large Millimeter/submillimeter Array and the South Pole Telescope.
  • Discuss the EHT collaboration and organize the EHT community.

To register for this conference, please click here

There will be a poster session held during this conference.  Please contact Stephanie if you are interested in presenting a poster.

The Event Horizon Telescope has been made possible by support from:

EHT 2014 has received additional support from:

Kazunori Akiyama, National Astronomical Observatory of Japan
Keiichi Asada, Academia Sinica Institute of Astronomy and Astrophysics
Geoff Bower, Academia Sinica Institute of Astronomy and Astrophysics
Avery Broderick, Perimeter Institute & University of Waterloo
Andrew ChaelHarvard-Smithsonian Center for Astrophysics
Jim Cordes, Cornell University
Geoffrey CrewMIT Haystack Observatory
Jason Dexter, University of California, Berkeley
Shep Doeleman, MIT Haystack Observatory
Frank Eisenhauer, Max Planck Institute for Extraterristrial Physics
Heino Falcke, Radboud University Nijmegen
Vincent Fish, MIT Haystack Observatory
Elena Gallo, University of Michigan
Charles Gammie, University of Illinois
Andrea Ghez, University of California, Division of Astronomy & Astrophysics
Kayhan Gultekin, University of Michigan
Michael Hecht, MIT Haystack Observatory
Tim Johannsen, Perimeter Institute
Michael Johnson, Harvard-Smithsonian Center for Astrophysics
Sergei Komissarov, University of Leeds
Michael Kramer, Max Planck Institute for Radio Astronomy
Thomas Krichbaum, Max Planck Institute for Radio Astronomy
Colin Lonsdale, MIT Haystack Observatory
Ru-Sen Lu, MIT Haystack Observatory
Sera Markoff, University of Amsterdam
Dan Marrone, University of Arizona
Ivan Marti-Vidal, Onsala Space Observatory
Samir Mathur, Ohio State University
Jeff McClintock, Harvard Smithsonian Center for Astrophysics
Jonathan McKinney, University of Maryland
John Monnier, University of Michigan
Monika Moscibrodzka, Radboud University Nijmegen
Masanori Nakamura, Academia Sinica Institute of Astronomy and Astrophysics
Dimitrios Psaltis, University of Arizona
Eliot Quataert, University of California, Berkeley
Laleh SadeghianUniversity of Wisconsin-Milwaukee
Xavier Siemens, University of Wisconsin-Milwaukee
Alexander Tchekhovskoy, University of California, Berkeley
Remo TilanusRadboud University Nijmegen
Laura VertatschitschHarvard Smithsonian Center for Astrophysics
Marta Volonteri, Paris Institute of Astrophysics
Jonelle Walsh, Texas A&M University
John Wardle, Brandeis University
 
 
  • Kazunori Akiyama, National Astronomical Observatory of Japan
  • Keiichi Asada, Academia Sinica Institute of Astronomy and Astrophysics
  • James Bardeen, University of Washington
  • Geoff Bower, Academia Sinica Institute of Astronomy and Astrophysics
  • Christiann Brinkerink, Radboud University Nijmegen
  • Avery Broderick, Perimeter Institute & University of Waterloo
  • Alejandro Cardenas-Avendano, Universidad Nacional de Colombia
  • Andrew ChaelHarvard-Smithsonian Center for Astrophysics
  • Laura Chajet, York University
  • Pierre Christian, Harvard University
  • Riley Connors, University of Amsterdam
  • Jim Cordes, Cornell University
  • Geoffrey Crew, MIT Haystack Observatory
  • Jason Dexter, University of California, Berkeley
  • Shep Doeleman, MIT Haystack Observatory
  • Salome DibiRadboud University Nijmegen
  • Frank Eisenhauer, Max Planck Institute for Extraterristrial Physics
  • Heino Falcke, Radboud University Nijmegen
  • Vincent FishMIT Haystack Observatory
  • Seth Fletcher, Scientific American
  • Valeri Frolov, University of Alberta
  • Elena Gallo, University of Michigan
  • Charles Gammie, University of Illinois
  • Andrea Ghez, University of California, Division of Astronomy & Astrophysics
  • Ciriaco GoddiRadboud University Nijmegenz
  • Jose L. GomezInstituto Astrofisica Andalucia-CSIC
  • Gabriela Gonzalez, Louisiana State University
  • Stephen Green, Perimeter Institute
  • Kayhan Gultekin, University of Michigan
  • Kazuhiro HadaNational Astronomical Observatory of Japan
  • Michael Hecht, MIT Haystack Observatory
  • Mareki Honma, National Astronomical Observatory of Japan
  • Makoto Inoue, Academia Sinica Institute of Astronomy and Astrophysics
  • Tim Johannsen, Perimeter Institute
  • Michael Johnson, Harvard-Smithsonian Center for Astrophysics
  • Svetlana Jorstad, Boston University
  • Mansour Karami, Perimeter Institute
  • Junhan Kim, Univeristy of Arizona
  • Makoto KinoAcademia Sinica Institute of Astronomy and Astrophysics
  • Sergei Komissarov, University of Leeds
  • Thomas Krichbaum, Max Planck Institute for Radio Astronomy
  • Michael Kramer, Max Planck Institute for Radio Astronomy
  • Kara Kundert, University of Michigan
  • Robert Laing, European Southern Observatory
  • Michael Landry, LIGO Hanford Observatory
  • Luis Lehner, Perimeter Institute
  • Laurent Loinard, CRyA-UNAM
  • Colin Lonsdale, MIT Haystack Observatory
  • Ru-Sen Lu, MIT Haystack Observatory
  • Sera Markoff, University of Amsterdam
  • Dan Marrone, University of Arizona
  • Alan Marscher, Boston University
  • Ivan Marti-Vidal, Onsala Space Observatory
  • Samir Mathur, Ohio State University
  • Satoki MatsushitaAcademia Sinica Institute of Astronomy and Astrophysics
  • Jeff McClintock, Harvard Smithsonian Center for Astrophysics
  • Jonathan McKinney, University of Maryland
  • John Moffat, Perimeter Institute
  • John Monnier, University of Michigan
  • Monika Moscibrodzka, Radboud University Nijmegen
  • Masanori Nakamura, Academia Sinica Institute of Astronomy and Astrophysics
  • Monica Orienti, INAF-IRA
  • Gisela Ortiz, Universidad Nacional Autónoma de México
  • Nestor Ortiz, Perimeter Institute
  • Dimitrios Psaltis, University of Arizona
  • Hung-Yi PuAcademia Sinica Institute of Astronomy and Astrophysics
  • Eliot Quataert, University of California, Berkeley
  • Luciano Rezzolla, Institute for Theoretical Physics
  • Freek RoelofsRadboud University Nijmegen
  • Eduardo RosMax Planck Institute for Radio Astronomy
  • Laleh Sadeghian, University of Wisconsin-Milwaukee
  • Mohamad Shalaby, Perimeter Institute
  • Xavier Siemens, University of Wisconsin-Milwaukee
  • Fumie Tazaki, National Astronomical Observatory of Japan
  • Alexander Tchekhovskoy, University of California, Berkeley
  • Remo TilanusRadboud University Nijmegen
  • Ilse Van Bemmel, JIVE
  • Laura VertatschitschHarvard Smithsonian Center for Astrophysics
  • Marta Volonteri, Paris Institute of Astrophysics
  • Jonelle Walsh, Texas A&M University
  • John Wardle, Brandeis University
  • Jonathan Weintroub, Harvard Smithsonian Center for Astrophysics
  • Huan Yang, Perimeter Institute
  • Andre Young, Stellenbosch University

Schedule is subject to change

Poster Session:
Participants have been encouraged to present posters; they will be displayed in the Atrium for the duration of the conference.

Monday, November 10, 2014

Time

Event

Location

8:30 – 9:00am

Registration

Reception

9:00 – 9:25am

Shep Doeleman, MIT Haystack Observatory
Introduction to EHT

Theater

9:25 – 9:50am

Marta Volonteri, Paris Institute of Astrophysics
Growth of supermassive black holes and their relationships to their host galaxies

Theater

9:50 – 10:15am

Jeff McClintock, Harvard Smithsonian Center for Astrophysics
Measuring the Spins of Black Holes

Theater

10:15 – 10:45am

Coffee Break

Bistro – 1st Floor

10:45 – 11:10am

Jonathan McKinney, University of Maryland
Polarized emission from Black Hole Accretion Disks and Jets

Theater

11:10 – 11:35am

Andrea Ghez,
University of California, Division of Astronomy & Astrophysics
TBA

Theater

11:35 – 12:00pm

Sera Markoff, University of Amsterdam
TBA

Theater

12:00 – 12:25pm

Geoff Bower,
Academia Sinica Institute of Astronomy & Astrophysics
The Size and Morphology of Sgr A* at 7mm

Theater

12:25 – 1:00pm

Charles Gammie, University of Illinois
Discussion 1

Theater

1:00 – 2:30pm

Lunch

Bistro – 1st Floor

2:30 – 2:55pm

Eliot Quataert, University of California, Berkeley
TBA

Theater

2:55 – 3:20pm

Vincent Fish, MIT Haystack Observatory
Detection and Variability of Closure Phases in Sgr A*

Theater

3:20 – 3:45pm

Michael Johnson,
Harvard-Smithsonian Center for Astrophysics
TBA

Theater

3:45 – 4:10pm

John Monnier, University of Michigan
Optimized Image Reconstruction:
Insights from Optical Interferometry

Theater

4:10 – 4:40pm

Coffee Break

Bistro – 1st Floor

4:40 – 6:00pm

Avery Broderick, Perimeter Institute
Discussion 2

Theater

Tuesday, November 11, 2014

Time

Event

Location

9:00 – 9:25am

Heino Falcke, Radboud University Nijmegen
Jets and the radio emission from supermassive black holes

Theater

9:25 – 9:50am

Elena Gallo, University of Michigan
State transitions in accreting black holes: X-ray binaries vs. AGN

Theater

9:50 – 10:15am

Sergei Komissarov, University of Leeds
TBA

Theater

10:15 – 10:45am

Coffee Break

Bistro – 1st Floor

10:45 – 11:10am

Kayhan Gultekin, University of Michigan
Stellar Dynamical Measurements of the Black Hole in M87 and Friends

Theater

11:10 – 11:35am

Monika Moscibrodzka, Radboud University Nijmegen
Two-temperature disk + isothermal jet model for Sgr A* and M87

Theater

11:35 – 12:00pm

Keiichi Asada,
Academia Sinica Institute of Astronomy & Astrophysics
mm and sub-mm polarimetry of accretion flow towards M 87

Theater

12:00 – 12:25pm

Masanori Nakamura,
Academia Sinica Institute of Astronomy & Astrophysics
TBA

Theater

12:25 – 1:00pm

John Wardle, Brandeis University
Discussion 3

Theater

1:00 – 2:30pm

Lunch

Bistro – 1st Floor

2:30 – 2:55pm

Ru-Sen Lu, MIT Haystack Observatory
TBA

Theater

2:55 – 3:20pm

Thomas Krichbaum,
Max Planck Institute for Radio Astronomy
New Results from Global Millimeter VLBI observations -
How small an AGN can be ?

Theater

3:20 – 3:45pm

Kazunori Akiyama,
National Astronomical Observatory of Japan
TBA

Theater

3:45 – 4:10pm

Alexander Tchekhovskoy, University of California, Berkeley
TBA

Theater

4:10 – 4:40pm

Coffee Break

Bistro – 1st Floor

4:40 – 6:00pm

Shep Doeleman, MIT Haystack Observatory
Discussion 4

Theater

Wednesday, November 12, 2014

Time

Event

Location

9:00 – 9:25am

Samir Mathur, Ohio State University
TBA

Theater

9:25 – 9:50am

Laleh Sadeghian, University of Wisconsin-Milwaukee
Advanced LIGO status and prospects to probe the strong gravity regime

Theater

9:50 – 10:15am

Xavier Siemens, University of Wisconsin-Milwaukee
TBA

Theater

10:15 – 10:45am

Coffee Break

Bistro – 1st Floor

10:45 – 11:10am

Jonelle Walsh, Texas A&M University
Gas Dynamical Black Hole Mass Measurements for M87

Theater

11:10 – 11:35am

 Frank Eisenhauer,
Max Planck Institute for Extraterristrial Physics
GRAVITY - Exploring Physics Close to the Galactic Center Black Hole with Infrared Interferometry

Theater

11:35 – 12:00pm

Jim Cordes, Cornell University
TBA

Theater

12:00 – 12:25pm

Tim Johannsen, Perimeter Institute
Testing General Relativity with the EHT

Theater

12:25 – 2:00pm

Lunch

Bistro – 1st Floor

2:00 – 3:30pm

Michael Kramer, Max Planck Institute for Radio Astronomy
Colloquium

Theater

3:30 – 4:40pm

TBA
Discussion 5

Theater

6:30pm

Conference Dinner

Bistro – 1st Floor

Thursday, November 13, 2014

Time

Event

Location

8:15 – 9:00am

Remo Tilanus, Radboud University Nijmegen
TBA

Theater

9:00 – 9:25am

Shep Doeleman, MIT Haystack Observatory and
Dan Marrone, University of Arizona
TBA

Theater

9:25 – 10:30am

Array Site Reports

Theater

10:30 – 11:00am

Coffee Break

Bistro – 1st Floor

11:00 – 11:35pm

Array Site Reports cont.

Theater

11:35 – 12:00pm

Laura Vertatschitisch,
Harvard Smithsonian Center for Astrophysics
VLBI Backend Systems

Theater

12:00 – 12:25pm

Michael Hecht, MIT Haystack Observatory
TBA

Theater

12:25 – 1:00pm

TBA
TBA

Theater

1:00 – 2:30pm

Lunch

Bistro – 1st Floor

2:30 – 2:55pm

Ru-Sen Lu, MIT Haystack Observatory
TBA

Theater

2:55 – 3:20pm

Geoffrey Crew, MIT Haystack Observatory
TBA

Theater

3:20 – 3:45pm

Ivan Marti-Vidal, Onsala Space Observatory
Phased ALMA and high-fidelity polarimetry with the EHT

Theater

3:45 – 4:10pm

Michael Johnson, Harvard-Smithsonian Center for Astrophysics TBA

Theater

4:10 – 4:40pm

Coffee

Bistro – 1st Floor

4:40 – 6:00pm

Discussion 6

Theater

Friday, November 14, 2014

Time

Event

Location

9:00 - 9:50am Jason Dexter, University of California, Berkeley and
Dimitrios Psaltis, University of Arizona
TBA
Theater

9:50 – 10:15am

Andrew Chael, Harvard Smithsonian Center for Astrophysics
TBA

Theater

10:15 – 10:30am

Mareki Honma, National Astronomical Observatory of Japan
TBA

Theater

10:30 – 11:00am

Coffee

Bistro – 1st Floor

11:00 – 11:20am

Vincent Fish, MIT Haystack Observatory
Synthetic Data

Theater

11:20 – 12:00pm

Shep Doelman, MIT Haystack Observatory
EHT Wiki

Theater

12:00 – 1:30pm

Lunch

Bistro – 1st Floor

1:30 – 2:30pm

Status of CA

Theater

2:30 – 2:55pm

EHT Organization

Theater

2:55 – 3:20pm

EHT Site Agreements

Theater

3:20 – 3:45pm

Data Policy

Theater

3:45 – 4:10pm

Publication Policy

Theater

4:10 – 4:40pm

Science WG’s

Theater

4:40 -6:00pm

Discussion

Theater

 

 

Keiichi Asada, Academia Sinica Institute of Astronomy and Astrophysics

mm and sub-mm polarimetry of accretion flow towards M 87

Mass accretion rate on the SMBHs is one of the fundamental parameters used to investigate AGNs. Faraday Rotation Measure (RM) observations at mm/sub-mm wavelengths is one of the powerful methods to derive the mass accretion rate of hot accretion flows towards our galactic center, Sgr A* (e.g., Marrone et al. 2006). Based on this scheme, we conducted an SMA observation to apply this method to M 87, which is one of the primary target for our submm VLBI observations, in February 2013. We succeeded to derive an RM of (2.1 ± 1.8) × 10^5 rad m^-2, it gives the range of the mass accretion rate (M_dot) between 0 and 9.2 × 10^-4 M_sun yr^-1 at the distance of 21 rs from the SMBH. Our estimated M.is already two orders of magnitude smaller than the M_dot at the outer part of the accretion flow (~10^5 r_s) of 0.1 M_sun yr^-1 determined by X-ray observations (Di Matteo et al. 2003). This significant suppression of the M_dot at the inner region is expected with the radiatively inefficient accretion flow (RIAF) model.  With future submm VLBI polarimetry towards jetted sources including M 87, we will derive the profile of accretion flow along the jet.  It is very important itself for the study of the accretion process onto the SMBH, but also provide fundamental properties to derive BH parameters from the BH shadow imaging.

Geoff Bower, Academia Sinica Institute of Astronomy and Astrophysics

The Size and Morphology of Sgr A* at 7mm

Long wavelength measurements provide sensitive probes of the intrinsic structure of Sgr A* and of the scattering properties of the line-of-sight interstellar medium.  At this wavelength, scattering dominates the apparent size of the source but careful closure amplitude techniques can provide highly accurate structural information.  We present new results from the VLBA at 7mm wavelength that for the first time reveal two-dimensional intrinsic structure while also demonstrating the stability of the intrinsic size during periods of significant activity at NIR and X-ray wavelengths.  These results also demonstrate the stability of the scattering medium over time.  New observations of the Galactic Center pulsar PSR J1745-2900 show that the scattering properties of Sgr A* are spatially coherent over an angular scale of at least a few arc seconds.  Analysis of the angular and temporal broadening data for the pulsar place the scattering medium at a distance of kiloparsecs away from the Galactic Center, resolving a significant mystery regarding the scattering medium.

Frank Eisenhauer, Max Planck Institute for Extraterristrial Physics

GRAVITY - Exploring Physics Close to the Galactic Center Black Hole with Infrared Interferometry

GRAVITY is a new instrument combining the four 8m ESO Very Large Telescopes in Chile. Other than the BlackHoleCam / EHT with its focus on imaging the shadow of the black hole against the surrounding accretion flow, the goal of GRAVITY is to measure dynamical processes in the immediate vicinity of the black hole, for example the motion of matter close to the last stable orbit and relativistic effects in stellar orbits. Our presentation covers the experimental and astrophysical aspects of this project and highlights the complementarity with the submm interferometry to overcome the degeneracies in modelling the observations.

Heino Falcke, Radboud University Nijmegen

Jets and the radio emission from supermassive black holes

Vincent Fish, MIT Haystack Observatory

Detection and Variability of Closure Phases in Sgr A*

Closure phases measured on the Arizona-California-Hawaii triangle of the EHT over multiple years indicate that the 1.3 mm structure of Sgr A* is asymmetric on scales of a few Schwarzschild radii.  The closure phase data provide new constraints on models of the quiescent emission from Sgr A*.  Time variability in the closure provides evidence of structural changes on scales resolved by millimeter-wavelength VLBI.
We discuss these results as well as other implications of the data.
 
Vincent Fish, MIT Haystack Observatory
 
Synthetic Data
 
You've just finished running your code, and you're certain that you (and only you) know exactly what the region around a supermassive black hole looks like.  You could lie back and wait for the accolades to roll in, but why not take an extra moment to make testable predictions that even the observers can understand?  Synthetic data can help.
 
Elena Gallo, University of Michigan
 
State transitions in accreting black holes: X-ray binaries vs. AGN
 
Stellar mass black hole in X-ray binaries offer a neat laboratory for understanding accretion and its interplay with the production of relativistic outflows. Here, I will review our phenomenological understanding of how major changes in the accretion flow translate into different outflow properties in Galactic X-ray binary. Notwithstanding the severe limitations posed by the different evolution and feeding mechanism, I will discuss how the different states of black hole X-ray binaries can be mapped into different classes of accreting super-massive black holes in AGN, with implications for their feedback modeling. 
 
Kayhan Gultekin, University of Michigan
 
Stellar Dynamical Measurements of the Black Hole in M87 and Friends
 
Tim Johannsen, Perimeter Institute
 
Testing General Relativity with the EHT
 
Thomas Krichbaum, Max Planck Institute for Radio Astronomy
 
New Results from Global Millimeter VLBI observations - How small an AGN can be?
 
VLBI observations at the highest possible frequency penetrate the opacity barrier in the nuclear regions of radio-galaxies and blazars, which are synchrotron self-absorbed at longer wavelength. This facilitates a direct and sharper than ever view into the 'heart' of Active Galactic Nuclei (AGN), into region in which BH physics and general relativity effects become important and where radio jets are launched. Here we report on new results from global 3mm and 1.3mm VLBI observations adding the APEX and IRAM to the Event Horizon Telescope. New images and core size estimates for a number of AGN jets and for Sgr A* are presented and discussed.
 
Ivan Marti-Vidal, Onsala Space Observatory
 
Phased ALMA and high-fidelity polarimetry with the EHT
 
Circular polarization feeds are preferred for a robust calibration of VLBI observations. Indeed, most VLBI stations record in a circular polarization basis. However, all wide-band receivers (including those of ALMA) observe in linear polarization basis. We will discuss on the procedure followed to solve the problem of linear feeds in the Phased-ALMA polarization conversion for VLBI. We will show how a high-fidelity polarimetry can be obtained with our approach, when the Phased-ALMA signal is combined with circular-polarization signals from other VLBI stations. We will also discuss on the possibility, advantages and disadvantages, of using the same polarimetry strategy on other future VLBI stations with linear feeds (to increase the achievable bandwidth in VLBI). We will also present test results with real data, obtained from a 3mm fringe test among two EVN stations. Preliminary results from real ALMA Phasing data may also be shown.
 
Jeff McClintock, Harvard Smithsonian Center for Astrophysics
 
Measuring the Spins of Black Holes
 
Both the continuum-fitting and Fe-line methods of measuring black hole spin will be discussed and compared, with attention to sources of systematic error.  Both methods rely on estimating the inner radius of the black hole's accretion disk and identifying it with the radius of the ISCO.  The Fe-line method is extremely important because of its dominant role in measuring the spins of supermassive black holes, which is problematic for the continuum-fitting method.  Meantime, both methods are applicable to stellar-mass black holes, and we will discuss current efforts to cross-check the spins of individual black holes.  Finally, a comprehensive summary of spin results for both stellar-mass and supermassive black holes will be presented.
 
Jonathan McKinney, University of Maryland
 
Polarized emission from Black Hole Accretion Disks and Jets
 
We discuss how polarized emission can place constraints on the properties of accretion flows and jets in the strong gravity regime for systems like SgrA* and M87 being observed by the Event Horizon Telescope.
 
John Monnier, University of Michigan
 
Optimized Image Reconstruction: Insights from Optical Interferometry
 
The radio community pioneered the use of closure phases to allow interferometric imaging even when fringe phases are compromised by atmospheric turbulence or unstable reference clocks.  Eventually, better receivers and observing methods allowed phase referencing to provide direct measures of complex visibilities and eased the uncertainties using Fourier inversions required for imaging.  At the same time, optical and infrared (O/IR) interferometers have been developed recently that can combine up to 6 telescopes simultaneously, at which point the inadequacies of classic imaging methods such as CLEAN were apparent. Here I report on dramatic progress within the O/IR interferometry to develop new image reconstruction techniques taking advantage of advances in ``compressed sensing'' theory and new approaches afforded by modern computing.  Because the Event Horizon Telescope must rely on closure phases instead of direct Fourier phases, the new algorithms from the O/IR could be essential to extracting the most information from EHT observations and we demonstrate promising results using simulated EHT data.
 
Monika Moscibrodzka, Radboud University Nijmegen
 
Two-temperature disk + isothermal jet model for Sgr A* and M87
 
The super-massive black hole in the center of the Milky Way, Sgr~A*, displays a nearly flat radio spectrum which is typical for jets in Active Galactic Nuclei. Indeed, time-dependent, magnetized models of radiatively inefficient accretion flows, which are commonly used to explain emission of Sgr A* also often produce jet-like outflows. However, the emission from these models so far has failed to reproduce the flat radio spectrum. We show that current GRMHD simulations can naturally reproduce the flat spectrum, when using a two-temperature plasma in the disk and a constant electron temperature plasma in the jet. This assumption is consistent with current state-of-the art simulations, in which the electron temperature evolution is not explicitly modeled.  The model images and spectra are consistent with the radio sizes and spectrum of Sgr~A*. The model can also reproduce the radio images of the jet base in M87.
 
Laleh Sadeghian, University of Wisconsin-Milwaukee
 
Advanced LIGO status and prospects to probe the strong gravity regime
 
Gravitational waves will allow scientists to test Einstein’s theory of General Relativity in the previously unexplored strong-field regime. Einstein’s theory of general relativity, as the most accepted theory of gravity, has been greatly constrained in the quasi-linear, quasi-stationary regime, where gravity is weak and velocities are small. Gravitational waves may carry information about highly dynamical and strong-field gravity that is required to generate measurable waves. Coalescing compact binaries are the most promising sources of gravitational waves accessible to ground-based interferometers, such as Advanced LIGO. Made of neutron stars and/or black holes that orbit each other hundreds of times a second just before they collide, the resulting waves are imprinted with information about the individual objects and the dynamical coalescence process. After reviewing the basic properties of gravitational waves, I will present an overview of the detector design and provide an update on the current status of Advanced LIGO and its ability to probe the strong gravity regime.
 
Laura Vertatschitsch, Harvard Smithsonian Center for Astrophysics
 
VLBI Backend Systems
 
The EHT data acquisition campaign in March 2015 will utilize new digital backends on many of the new and existing sites. We will briefly overview the state of the art for wideband digital backends for VLBI and discuss the several flavors that will be employed this coming year. Specifically, we will focus on details of the Roach2 Digital Backend (R2DBE), a new 16 Gbps wideband DBE unit that can be scaled to 64 Gbps, to be employed at single dish sites. The R2DBE digitizes 2.048 GHz of RF in each of two inputs and sends 8 Gbps single-channel data on each of two 10 GbE links to a Mark 6 data recorder with expansion chassis for a total of 16 Gbps. The system utilizes open source hardware, firmware, and software developed through the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). Engineers at SAO have been members and developers for the CASPER group for several years, thus the challenge of rapidly prototyping a VLBI backend system on a limited budget and short time scale could be met by drawing on years of previous development and expertise. In four months the system was developed and demonstrated in 32 Gbps form for the South Pole Telescope, achieving fringes in a hybrid correlation between an R2DBE and an existing R1DBE. We present the tests and results achieved with the R2DBE 32 Gbps system for the South Pole, and upcoming developments in preparation for March 2015. 
 
Marta Volonteri, Paris Institute of Astrophysics
 
Growth of supermassive black holes and their relationships to their host galaxies
 
Black holes are the engines that power quasars and active galactic nuclei throughout cosmic time. The masses of black holes in nearby galaxies define clear correlations with the properties of their host galaxies. These results suggest that black holes, while a thousand times lighter than the galaxy, grow alongside their hosts during its cosmic evolution. I will discuss the growth of black holes, and the establishment of the connection between galaxies and black holes. 
 
Jonelle Walsh, Texas A&M University
 
Gas Dynamical Black Hole Mass Measurements for M87
 
M87 is one of the most luminous nearby galaxies and hosts one of the most massive black holes known, making it a very important target for extragalactic studies. The supermassive black hole has been the subject of several stellar and gas dynamical mass measurements; however, the best current stellar dynamical black hole mass is larger than the gas dynamical determination by a factor of two, corresponding to a 2-sigma discrepancy. In this talk, I will review the gas dynamical black hole mass measurements that have been made over the years for M87, focusing in particular on the most recent measurement from multi-slit Space Telescope Imaging Spectrograph observations from the Hubble Space Telescope. I will also discuss the strengths and weaknesses generally associated with stellar and gas dynamical black hole mass measurement methods, and the current state of cross-checks between the two methods that have been carried out within the same galaxy.

If you need transportation while attending the conference, we offer suggestions below. If flying, we suggest that you book your flight to arrive at Toronto International Airport (YYZ) or the Region of Waterloo International Airport (YKF).


Boulevard Limousine (estimated travel time 1hr) The fare for Boulevard Limousine for one passenger is $118.00 to the Toronto Airport.  The fare for one passenger from the Toronto Airport to Waterloo is $133.00.  To make reservations, please visit their website or call 519-886-8090.


Airways Transit (estimated travel time 1hr) Airways Transit connects Toronto Pearson airport with the Waterloo area providing 24 hour door to door shared ride service. For Toronto Pearson airport transfers we have obtained a reduced conference fare of $69.00 per person, one way, tax included. To receive the reduced fare you must book in advance.

Book online at: http://conferences.airwaystransit.com  Enter booking code: EHT 2014 (enter exactly as shown).

By phone 24 hrs: 519 886 2121 – Identify yourself as an EHT delegate. 


0001 Toronto Cabs (estimated travel time 1hr)  Approximately $160.00 rate for one-way: Toronto International Airport to Waterloo. Call 416-809-5656. 
Note: One or more passengers can split this $90.00 rate.


Car Rentals Upon arrival in any of the terminals at Pearson International Airport there are a number of car rental agencies to choose from. Their booths are located on the arrivals level. The cost of a car rental is dependent upon the type of vehicle you would like and the length of the stay. 

Driving Directions 

  • From the airport, follow signs for Highway 427 South/Highway 401.  
  • Continue to follow signs for Highway 401 West - London.  
  • Proceed West on Highway 401.  
  • Exit Highway 401 at Highway 8 West.  
  • Take exit 278 (Highway 8 West) and follow 8 West for 5 km to Highway 85, towards Highway 7 East. 
  • Proceed on Highway 85 for 5 km to Bridgeport Road exit. Turn right at the off-ramp, traveling west.  
  • Follow Bridgeport Road for 2 km into downtown Waterloo.  
  • Bridgeport is a four-lane one-way road. It becomes Caroline Street at Albert Street. Continue straight ahead.  
  • Travel forward another 200 metres, but ease over into the right-hand lane. As you go down a hill and around a curve, look for the green Perimeter Institute sign on the right hand side. The parking lot entrance is just after the sign (past the historic grist mill that sits on the edge of Silver Lake).  
  • Turn right into the PI parking lot entrance.

If you need accommodations while attending the conference, we offer suggestions for lodging below.


Delta Waterloo 110 Erb Street West Waterloo ON N2L 0C6 Phone: 1-888-890-3222
Distance from PI: 450 m


Waterloo Hotel 2 King Street North Waterloo, ON N2J 2W7 Phone: 519-885-2626 Distance from PI: 500 m


Waterloo Inn 475 King Street North Waterloo, ON N2J 2Z5 Reservation line: 1-800-361-4708 Reservation e-mail: reserve@waterlooinn.com Distance from PI: 3 km


Walper Terrace Hotel 1 King Street West Kitchener, ON N2G 1A1 Phone: 519-745-4321 Distance from PI: 4 km


Courtyard by Marriott 50 Benjamin Road East St. Jacobs, ON N2V 2J9 Phone: 519-884-9295 Distance from PI: 5.6 km

Scientific Organizers:

  • Avery Broderick, Perimeter Institute & University of Waterloo
  • Shep Doeleman, MIT Haystack Observatory
  • Luis Lehner, Perimeter Institute
  • John Moffat, Perimeter Institute
  • Dimitrios Psaltis, University of Arizona
  • Jonathan Weintroub, Harvard Smithsonian Center for Astrophysics

Scientific Organizing Committee:

  • Heino Falcke, Radbout University Nimegen
  • Gabriela Gonzalez, Louisiana State University
  • Paul Ho, Academia Sinica Institute of Astronomy and Astrophysics
  • Mareki Honma, National Astronomical Observatory of Japan
  • Michael Kramer, Max Planck Institute for Radio Astronomy
  • Sera Markoff, University of Amsterdam
  • Dan Marrone, University of Arizona
  • John Wardle, Brandeis University
  • Anton Zensus, Max Planck Institute for Radio Astronomy
  • Lucy Ziurys, University of Arizona