Search Publications
Searching for FUV line emission from 107 K gas in massive elliptical galaxies and galaxy clusters as a tracer of turbulent velocities
Anderson, Michael E.; Sunyaev, Rashid
Non-thermal pressure from turbulence and bulk flows is a fundamental ingredient in hot gaseous haloes, and in the intracluster medium, it will be measured through emission line kinematics with calorimeters on future X-ray spacecraft. In this paper, we present a complementary method for measuring these effects, using forbidden FUV emission lines of…
Hubble Space Telescope Constraints on the Winds and Astrospheres of Red Giant Stars
Harper, Graham M.; Wood, Brian E.; Müller, Hans-Reinhard
We report on an ultraviolet spectroscopic survey of red giants observed by the Hubble Space Telescope, focusing on spectra of the Mg II h and k lines near 2800 Å in order to study stellar chromospheric emission, winds, and astrospheric absorption. We focus on spectral types between K2 III and M5 III, a spectral type range with stars that are nonco…
On the void explanation of the Cold Spot
Martínez-González, E.; Vielva, P.; Marcos-Caballero, A. +1 more
The integrated Sachs-Wolfe (ISW) contribution induced on the cosmic microwave background by the presence of a supervoid as the one detected by Szapudi et al. (2015) is reviewed in this letter in order to check whether it could explain the Cold Spot (CS) anomaly. Two different models, previously used for the same purpose, are considered to describe…
Possible interpretation of the precession of comet 67P/Churyumov-Gerasimenko
Jorda, L.; Lara, L. M.; Lamy, P. +52 more
Context. Data derived from the reconstruction of the nucleus shape of comet 67P/Churyumov-Gerasimenko (67P) from images of the OSIRIS camera onboard ROSETTA show evidence that the nucleus rotates in complex mode. First, the orientation of the spin axis is not fixed in an inertial reference frame, which suggests a precessing motion around the angul…
On the origin of the ionosphere at the Moon using results from Chandrayaan-1 S band radio occultation experiment and a photochemical model
Choudhary, R. K.; Bhardwaj, Anil; Dhanya, M. B. +2 more
The origin of the Moon's ionosphere has been explored using Chandrayaan-1 radio occultation (RO) measurements and a photochemical model. The electron density near the Moon's surface, obtained on 31 July 2009 (∼300 cm-3), is compared with results from a model which includes production and recombination of 16 ions, solar wind proton charg…
The JCMT Gould Belt Survey: evidence for radiative heating and contamination in the W40 complex
White, G. J.; Marsh, K.; Ward-Thompson, D. +56 more
We present SCUBA-2 450 µm and 850 µm observations of the W40 complex in the Serpens-Aquila region as part of the James Clerk Maxwell Telescope (JCMT) Gould Belt Survey (GBS) of nearby star-forming regions. We investigate radiative heating by constructing temperature maps from the ratio of SCUBA-2 fluxes using a fixed dust opacity spect…
A Candidate Planetary-mass Object with a Photoevaporating Disk in Orion
Fang, Min; Pascucci, Ilaria; Apai, Dániel +2 more
In this work, we report the discovery of a candidate planetary-mass object with a photoevaporating protoplanetary disk, Proplyd 133-353, which is near the massive star θ 1 Ori C at the center of the Orion Nebula Cluster (ONC). The object was known to have extended emission pointing away from θ 1 Ori C, indicating ongoing exte…
Spaced-based search coil magnetometers
Hospodarsky, George B.
Search coil magnetometers are one of the primary tools used to study the magnetic component of low-frequency electromagnetic waves in space. Their relatively small size, mass, and power consumption, coupled with a good frequency range and sensitivity, make them ideal for spaceflight applications. The basic design of a search coil magnetometer cons…
Evidence from SOFIA Imaging of Polycyclic Aromatic Hydrocarbon Formation along a Recent Outflow in NGC 7027
Sahai, R.; Ressler, M. E.; Lau, R. M. +1 more
We report spatially resolved (FWHM ∼ 3.″8-4.″6) mid-IR imaging observations of the planetary nebula (PN) NGC 7027 taken with the 2.5 m telescope on board the Stratospheric Observatory for Infrared Astronomy (SOFIA). Images of NGC 7027 were acquired at 6.3, 6.6, 11.1, 19.7, 24.2, 33.6, and 37.1 µ {{m}} using the Faint Object Infrared Camera f…
Observational aspects of galactic accretion at redshift 3.3
Rauch, Michael; Haehnelt, Martin G.; Becker, George D.
We investigate the origin of extragalactic continuum emission and its relation to the stellar population of a recently discovered peculiar z = 3.344 Ly α emitter. Based on an analysis of the broad-band colours and morphology, we find further support for the idea that the underlying galaxy is being fed by a large-scale (L ≥ 35 kpc) accretion stream…