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We predict how protoplanetary disks around low-mass young stars would appear in molecular lines observed with the ALMA interferometer. Our goal is to identify those molecules and transitions that can be used to probe and distinguish between…

Astrophysics · Physics 2009-11-13 D. Semenov , Ya. Pavlyuchenkov , Th. Henning , S. Wolf , R. Launhardt

Laser frequency stabilization is a critical part of the interferometry measurement system of space-based gravitational wave observatories such as the Laser Interferometer Space Antenna (LISA). Arm locking as a proposed frequency…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Yinan Yu , Shawn Mitryk , Guido Mueller

A space-based far-infrared interferometer could work synergistically with the James Webb Space Telescope (JWST) and the Atacama Large Millimeter Array (ALMA) to revolutionize our understanding of the astrophysical processes leading to the…

Laboratory optical atomic clocks achieve remarkable accuracy (now counted to 18 digits or more), opening possibilities to explore fundamental physics and enable new measurements. However, their size and use of bulk components prevent them…

Interferometric imaging now achieves angular resolutions as fine as 10 microarcsec, probing scales that are inaccessible to single telescopes. Traditional synthesis imaging methods require calibrated visibilities; however, interferometric…

Instrumentation and Methods for Astrophysics · Physics 2018-04-25 Andrew A. Chael , Michael D. Johnson , Katherine L. Bouman , Lindy L. Blackburn , Kazunori Akiyama , Ramesh Narayan

We present new measurements of the millimeter wavelength continuum emission from the long period variable Mira ($o$ Ceti) at frequencies of 46 GHz, 96 GHz, and 229 GHz ($\lambda$~7 mm, 3 mm, and 1 mm) based on observations obtained with the…

Solar and Stellar Astrophysics · Physics 2015-08-06 L. D. Matthews , M. J. Reid , K. M. Menten

For the laser interferometer space antenna (LISA) to reach it's design sensitivity, the coupling of the free running laser frequency noise to the signal readout must be reduced by more than 14 orders of magnitude. One technique employed to…

General Relativity and Quantum Cosmology · Physics 2009-12-17 Kirk McKenzie , Robert E. Spero , Daniel A. Shaddock

The ALMA North American and European prototype antennas have been evaluated by a variety of measurement systems to quantify the major performance specifications. Nearfield holography was used to set the reflector surfaces to 17 microns RMS.…

Context. Submillimeter Array (SMA) 870 micron polarization observations of the hot molecular core G31.41+0.31 revealed one of the clearest examples up to date of an hourglass-shaped magnetic field morphology in a high-mass star-forming…

In this lecture, we describe a number of advanced gain calibration techniques. In particular, self-calibration is an important tool in interferometric imaging at all wavelengths. It allows the observer to determine and remove residual phase…

Instrumentation and Methods for Astrophysics · Physics 2018-05-15 Crystal L. Brogan , Todd R. Hunter , Ed B. Fomalont

The success of an astronomical facility is measured by its scientific impact. A principal metric for this impact is the ensemble of peer-reviewed publications based on the observational data obtained by the facility. We present a…

We describe new results from the semiconductor-laser tracking frequency gauge, an instrument that can perform sub-picometer distance measurements and has applications in gravity research and in space-based astronomical instruments proposed…

Instrumentation and Methods for Astrophysics · Physics 2018-03-23 D. M. Kaplan , T. J. Roberts , J. D. Phillips , R. D. Reasenberg

The (sub)millimeter radiation of solar flares is poorly understood. Without spatial resolution, it cannot be compared easily to flare emissions in other wavelengths. The Atacama Large Millimeter-submillimeter Array (ALMA) offers sufficient…

Solar and Stellar Astrophysics · Physics 2023-02-01 I. Skokić , A. O. Benz , R. Brajša , D. Sudar , F. Matković , M. Bárta

Arm-locking is a technique for stabilizing the frequency of a laser in an inter-spacecraft interferometer by using the spacecraft separation as the frequency reference. A candidate technique for future space-based gravitational wave…

Instrumentation and Methods for Astrophysics · Physics 2016-02-17 James Ira Thorpe , Kirk McKenzie

We present observations of a solar plage in the millimeter-continuum with the ALMA and in the Ca 8542 and Na 5896 spectral lines with the Interferometric BIdimensional Spectrometer (IBIS). Our goal is to compare the measurement of local gas…

Solar and Stellar Astrophysics · Physics 2022-07-27 Ryan Hofmann , Kevin Reardon , Ivan Milic , Momchil Molnar , Yi Chai , Han Uitenbroek

Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants''. Accuracy achieved for the atomic optical frequency standards (optical clocks) approaches the level when…

Atomic Physics · Physics 2009-02-05 V. A. Dzuba , V. V. Flambaum.

ALMA will open a new chapter in the study of the Sun by providing a leap in spatial resolution and sensitivity compared to currently available mm wave- length observations. In preparation of ALMA, we have carried out a large number of…

Solar and Stellar Astrophysics · Physics 2015-12-15 Maria Loukitcheva , Sami K. Solanki , Stephen M. White , Mats Carlsson

High-frequency long-baseline experiments with the Atacama Large Millimeter/submillimeter Array were organized to test the high angular resolution imaging capabilities in the submillimeter wave regime using baselines up to 16 km. Four…

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