English
Related papers

Related papers: Simultaneous Six-way Observations from the Navy Pr…

200 papers

In order to understand the appropriate field of view (FOV) size of celestial automatic navigation systems for surface ships, we investigate the variations of measurement accuracy of star position and probability of successful star…

The first images of 6.7-GHz methanol masers in the massive star-forming regions DR21(OH) and DR21(OH)N are presented. By measuring the shapes, radial velocities and polarization properties of these masers it is possible to map out the…

Astrophysics · Physics 2009-11-13 L. Harvey-Smith , R. Soria-Ruiz , A. Duarte-Cabral , R. J. Cohen

An asymmetric surface brightness distribution of the rapidly rotating A7IV-V star, Altair, has been measured by the Navy Prototype Optical Interferometer (NPOI). The observations were recorded simultaneously using a triangle of three long…

Astrophysics · Physics 2009-11-10 Naoko Ohishi , Tyler E. Nordgren , Donald J. Hutter

We describe the recent modifications to the data reduction technique for observations acquired with the scanning Fabry-Perot interferometer (FPI) mounted on the 6-m telescope of the Special Astrophysical Observatory that allow the…

Instrumentation and Methods for Astrophysics · Physics 2015-12-09 A. V. Moiseev

The University of Sydney has a long history in optical stellar interferometry. The first project, in the 1960s, was the Narrabri Stellar Intensity Interferometer, which measured the angular diameters of 32 hot stars and established the…

Instrumentation and Methods for Astrophysics · Physics 2009-05-13 J. G. Robertson , J. Davis , M. J. Ireland , P. G. Tuthill , W. J. Tango , A. P. Jacob , J. R. North , T. A. ten Brummelaar

Radio interferometry is the current method of choice for deep space astronomy, but in the past few decades optical techniques have become increasingly common. This research seeks to characterize the performance of aperture masking…

Instrumentation and Methods for Astrophysics · Physics 2020-08-28 Kyle Morgenstein

A novel method capable of delivering relative optical path length metrology with nanometer precision is demonstrated. Unlike conventional dual-wavelength metrology which employs heterodyne detection, the method developed in this work…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Yitping Kok , Michael J. Ireland , J. Gordon Robertson , Peter G. Tuthill , Benjamin A. Warrington , William J. Tango

We present the results of 938 speckle measures of double stars and suspected double stars drawn mainly from the Hipparcos Catalogue, as well as 208 observations where no companion was noted. One hundred fourteen pairs have been resolved for…

Solar and Stellar Astrophysics · Physics 2015-10-28 Elliott P. Horch , Gerard T. van Belle , James W. Davidson, , Lindsay A. Ciastko , Mark E. Everett , Karen S. Bjorkman

Described here is the design and commissioning of a coronagraph facility for the 4.2 metre William Herschel Telescope (WHT) and its Nasmyth Adaptive Optics system for Multi-purpose Instrumentation (NAOMI). The use of the NAOMI system gives…

We predict mean angular diameters and amplitudes of angular diameter variations for all monoperiodic Pop.I Cepheids brighter than <V> = 8.0mag. The catalog is intended to aid selecting most promising Cepheid targets for future…

Astrophysics · Physics 2016-08-30 P. Moskalik , N. A. Gorynya

Emission from the 6.7 GHz methanol maser transition is very strong, is relatively stable, has small internal motions, and is observed toward numerous massive star-forming regions in the Galaxy. Our goal is to perform high-precision…

Astrophysics of Galaxies · Physics 2015-05-14 K. L. J. Rygl , A. Brunthaler , M. J. Reid , K. M. Menten , H. J. van Langevelde , Y. Xu

The uniform disk (UD) angular diameter measurements of two oxygen-rich Mira variables (AW Aur and BS Aur) and three semiregular (SRb) variables (GP Tau, RS Cap, RT Cap), in near Infrared K-band (2.2 micron) by lunar occultation observations…

Solar and Stellar Astrophysics · Physics 2015-05-30 Tapas Baug , T. Chandrasekhar

Context: In recent years, stellar intensity interferometry has seen renewed interest from the astronomical community because it can be efficiently applied to Cherenkov telescope arrays. Aims: We have investigated the accuracy that can be…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Michele Fiori , Giampiero Naletto , Luca Zampieri , Irene Jiménez Martínez , Carolin Wunderlich

The present articlereports on the first spatial intensity interferometry measurements on stars since the observations at Narrabri Observatory by Hanbury Brown et al. in the 1970's. Taking advantage of the progresses in recent years on…

Instrumentation and Methods for Astrophysics · Physics 2018-08-14 W. Guerin , J. -P. Rivet , M. Fouché , G. Labeyrie , D. Vernet , F. Vakili , R. Kaiser

Debate over the planet occurrence rates around intermediate-mass stars has hinged on the accurate determination of masses of evolved stars, and has been exacerbated by a paucity of reliable, directly-measured fundamental properties for…

We present mean angular diameters for two cepheid variables, alpha Ursae Minoris and zeta Geminorum, determined with the Navy Prototype Optical Interferometer (NPOI). We present linear radii for these cepheids and two additional cepheids,…

Interferometric observations with three telescopes or more provide two observables: closure phase information together with visibilities measurements. When using single-mode interferometers, both observables have to be redefined in the…

Astrophysics · Physics 2009-11-11 E. Tatulli , A. Chelli

Recent advances in telescope design, photodetector efficiency, and high-speed electronic data recording and synchronization have created the observational capability to achieve unprecedented angular resolution for several thousand bright…

We report 370 measures of 170 components of binary and multiple star systems, obtained from speckle imaging observations made with the Differential Speckle Survey Instrument at Lowell Observatory's Discovery Channel Telescope in 2015…

Based on CHARA Array measurements, we present the angular diameters of 23 nearby, main- sequence stars, ranging from spectral type A7 to K0, five of which are exoplanet host stars. We derive linear radii, effective temperatures, and…