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Jet-Launching Structure Resolved Near the Supermassive Black Hole in M87
(American Association for the Advancement of Science (AAAS), 2012)
Approximately 10% of active galactic nuclei exhibit relativistic jets, which are powered by accretion of matter onto super massive black holes. While the measured width profiles of such jets on large scales agree with ...
Resolved magnetic-field structure and variability near the event horizon of Sagittarius A
(American Association for the Advancement of Science (AAAS), 2015)
Near a black hole, differential rotation of a magnetized accretion disk is thought to produce an instability that amplifies weak magnetic fields, driving accretion and outflow. These magnetic fields would naturally give ...
Astrophysical Russian dolls
(Springer Nature, 2017)
Are there examples of "astrophysical Russian dolls," and what could we learn from their similarities? In this article, we list a few such examples, including disks, filaments, and clusters. We suggest that forging connections ...
First Season MWA EoR Power Spectrum Results at Redshift 7
(American Astronomical Society, 2016)
The Murchison Widefield Array (MWA) has collected hundreds of hours of Epoch of Reionization (EoR) data and now faces the challenge of overcoming foreground and systematic contamination to reduce the data to a cosmological ...
Delay Spectrum with Phase-Tracking Arrays: Extracting the HI power spectrum from the Epoch of Reionization
(American Astronomical Society, 2016)
The Detection of redshifted 21 cm emission from the epoch of reionization (EoR) is a challenging task owing to strong foregrounds that dominate the signal. In this paper, we propose a general method, based on the delay ...
The Interaction of Relativistic Spacecrafts with the Interstellar Medium
(American Astronomical Society, 2017)
The Breakthrough Starshot initiative aims to launch a gram-scale spacecraft to a speed of v∼0.2c, capable of reaching the nearest star system, α Centauri, in about 20 years. However, a critical challenge for the initiative ...
Lessons from Mayan Astronomy
The Mayan culture collected exquisite astronomical data for over a millennium. However, it failed to come up with the breakthrough ideas of modern astronomy because the data was analyzed within a mythological culture of ...
Interferometric Measurement of Acceleration at Relativistic Speeds
(American Astronomical Society, 2017)
We show that an interferometer moving at a relativistic speed relative to a point source of light offers a sensitive probe of acceleration. Such an accelerometer contains no moving parts, and is thus more robust than ...
Prospects for Characterizing the Atmosphere of Proxima Centauri B
(American Astronomical Society, 2016)
The newly detected Earth-mass planet in the habitable zone of Proxima Centauri could potentially host life - if it has an atmosphere that supports surface liquid water. We show that thermal phase curve observations with ...
Constraining the Milky Way mass with hypervelocity stars
(Elsevier BV, 2017)
Context. Although a variety of techniques have been employed for determining the Milky Way dark matter halo mass distribution, the range of allowed masses spans both light and heavy values. Knowing the precise mass of our ...