Search Publications
Astronomical imaging Fourier spectroscopy at far-infrared wavelengths
Naylor, David A.; Gom, Brad G.; van der Wiel, Matthijs H. D. +1 more
The principles and practice of astronomical imaging Fourier transform spectroscopy (FTS) at far-infrared wavelengths are described. The MachâZehnder (MZ) interferometer design has been widely adopted for current and future imaging FTS instruments; we compare this design with two other common interferometer formats. Examples of three instruments …
The Curious Radial Distributions of Horizontal Branch Stars in NGC 6441
Sandquist, Eric L.; Krogsrud, David A.; Kato, Tadafumi
NGC 6441 is one of the most massive and most metal-rich globular clusters in the galaxy, and is noted for an unusual extended horizontal branch that reaches past the instability strip. We find evidence that there are two different populations of stars within the heavily populated red clump. Once a differential reddening correction is applied, a la…
Correction to "Variation of the Martian ionospheric electron density from Mars Express radar soundings"
Gurnett, D. A.; Morgan, D. D.; Plaut, J. J. +3 more
Angular distribution of discontinuity normals of the interplanetary magnetic field
Erdős, G.; Lukács, K.
High time resolved (6 s) magnetic field data from the Helios-1 and Ulysses spacecrafts were used to investigate MHD discontinuities in the heliosphere. The identification of discontinuities was based on the rotation of the field vectors relative to the distance to the plasma in which the vectors were supposed to be frozen. In order to obtain the r…
The low-mass companion of HIP 45314 (HR 3672)
Neuhäuser, R.; Schmidt, T. O. B.; Mugrauer, M. +2 more
We report the discovery of a very low mass companion to HIP 45314 (HR 3672) located about 2.7 arcsec north-west of HR 3672 A. With four years of epoch difference between the two observations obtained with the Very Large Telescope we can reject by more than 4σ that B would be a non-moving background object unrelated to A. HR 3672 A is a B 7-8 main-…
Operation of CONSERT aboard Rosetta during the descent of Philae
Plettemeier, Dirk; Kofman, Wlodek; Herique, Alain +3 more
This paper presents a study investigating the performance of using the CONSERT instrument aboard the Rosetta spacecraft as a radar sounder during the Separation-Descent-Landing (SDL) phase of the Rosetta mission. Gathering scientifically valuable data during this phase will support CONSERT's primary target, the reconstruction of the 3D permittivit…
Investigating the Source of Planck-Detected AME: High-Resolution Observations at 15 GHz
Grainge, Keith J. B.; Hurley-Walker, Natasha; Scaife, Anna M. M. +1 more
The Planck 28.5 GHz maps were searched for potential Anomalous Microwave Emission (AME) regions on the scale of $\sim3^{\circ}$ or smaller, and several new regions of interest were selected. Ancillary data at both lower and higher frequencies were used to construct spectral energy distributions (SEDs), which seem to confirm an excess consistent wi…
An STIS Atlas of Ca II Triplet Absorption Line Kinematics in Galactic Nuclei
Axon, D.; Batcheldor, D.; Valluri, M. +2 more
The relations observed between supermassive black holes and their host galaxies suggest a fundamental link in the processes that cause these two objects to evolve. A more comprehensive understanding of these relations could be gained by increasing the number of supermassive black hole mass (M •) measurements. This can be achieved, in pa…
Doppler shift and broadening in solar wind turbulence
Glassmeier, K. -H.; Narita, Y.; Motschmann, U. +1 more
We propose a method to evaluate the Doppler shift and broadening using magnetic field data in solar wind turbulence. A model of the energy spectrum is constructed in the wavenumber-frequency domain in the direction of the mean flow, and it is compared with that determined directly from four-point magnetic field data of Cluster spacecraft using the…
Sub-millimeter observations of the terrestrial atmosphere during an Earth flyby of the MIRO sounder on the Rosetta spacecraft
Encrenaz, T.; Lee, S.; Gulkis, S. +5 more
Sub-millimeter spectra recorded by the MIRO sounder aboard the Rosetta spacecraft have been used at the time of an Earth flyby (November 2007) to check the consistency and validity of the instrumental data. High-resolution spectroscopic data were recorded in 8 channels in the vicinity of the strong water line at 557 GHz, and in a broad band contin…