Search Publications
Long-term trends of magnetic bright points. I. Number of magnetic bright points at disc centre
Veronig, A.; Utz, D.; Hanslmeier, A. +5 more
Context. The Sun shows an activity cycle that is caused by its varying global magnetic field. During a solar cycle, sunspots, I.e. extended regions of strong magnetic fields, occur in activity belts that are slowly migrating from middle to lower latitudes, finally arriving close to the equator during the cycle maximum phase. While this and other f…
Systematic Uncertainties in the Spectroscopic Measurements of Neutron-star Masses and Radii from Thermonuclear X-Ray Bursts. III. Absolute Flux Calibration
Marshall, Herman; Güver, Tolga; Özel, Feryal +3 more
Many techniques for measuring neutron star radii rely on absolute flux measurements in the X-rays. As a result, one of the fundamental uncertainties in these spectroscopic measurements arises from the absolute flux calibrations of the detectors being used. Using the stable X-ray burster, GS 1826-238, and its simultaneous observations by Chandra HE…
The data processing pipeline for the Herschel SPIRE Fourier Transform Spectrometer
Valtchanov, I.; Hopwood, R.; Lu, N. +13 more
We present the data processing pipeline to generate calibrated data products from the Spectral and Photometric Imaging Receiver (SPIRE) imaging Fourier Transform Spectrometer on the Herschel Space Observatory. The pipeline processes telemetry from SPIRE observations and produces calibrated spectra for all resolution modes. The spectrometer pipelin…
Spitzer IRAC Observations of IR Excess in Holmberg IX X-1: A Circumbinary Disk or a Variable Jet?
Roberts, T. P.; Berghea, C. T.; Dudik, R. P. +4 more
We present Spitzer Infrared Array Camera photometric observations of the ultraluminous X-ray source (ULX, X-1) in Holmberg IX. We construct a spectral energy distribution (SED) for Holmberg IX X-1 based on published optical, UV, and X-ray data combined with the IR data from this analysis. We modeled the X-ray and optical data with disk and stellar…
Evidence for dust-driven, radial plasma transport in Saturn's inner radiation belts
Krupp, N.; Roussos, E.; Krimigis, S. M. +4 more
A survey of Cassini MIMI/LEMMS data acquired between 2004 and 2015 has led to the identification of 13 energetic electron microsignatures that can be attributed to particle losses on one of the several faint rings of the planet. Most of the signatures were detected near L-shells that map between the orbits of Mimas and Enceladus or near the G-ring…
Subarcsecond bright points and quasi-periodic upflows below a quiescent filament observed by IRIS
Zhang, J.; Li, T.
Context. The new Interface Region Imaging Spectrograph (IRIS) mission provides high-resolution observations of UV spectra and slit-jaw images (SJIs). These data have become available for investigating the dynamic features in the transition region (TR) below the on-disk filaments.
Aims: The driver of "counter-streaming" flows along the filamen…
Scattering characteristics and imaging of energetic neutral atoms from the Moon in the terrestrial magnetosheath
Barabash, Stas; Futaana, Yoshifumi; Wieser, Martin +6 more
We study hydrogen energetic neutral atom (ENA) emissions from the lunar surface, when the Moon is inside the terrestrial magnetosheath. The ENAs are generated by neutralization and backscattering of incident protons of solar wind origin. First, we model the effect of the increased ion temperature in the magnetosheath (>10 times larger than that…
Foreground Bias from Parametric Models of Far-IR Dust Emission
Kogut, A.; Fixsen, D. J.
We use simple toy models of far-IR dust emission to estimate the accuracy to which the polarization of the cosmic microwave background can be recovered using multi-frequency fits, if the parametric form chosen for the fitted dust model differs from the actual dust emission. Commonly used approximations to the far-IR dust spectrum yield CMB residua…
The Hinode/XRT Full-Sun Image Corrections and the Improved Synoptic Composite Image Archive
Yoshimura, Keiji; Saar, Steven H.; Takeda, Aki
The XRT Synoptic Composite Image Archive (SCIA) is a storage and gallery of X-ray full-Sun images obtained through the synoptic program of the X-Ray Telescope (XRT) onboard the Hinode satellite. The archived images provide a quick history of solar activity through the daily and monthly layout pages and long-term data for morphological and quantita…
Dissecting a supernova impostor's circumstellar medium: MUSEing about the SHAPE of η Carinae's outer ejecta
Davidson, K.; Humphreys, R. M.; Mehner, A. +10 more
Aims: The role of episodic mass loss is one of the outstanding questions in massive star evolution. The structural inhomogeneities and kinematics of their nebulae are tracers of their mass-loss history. We conduct a three-dimensional morpho-kinematic analysis of the ejecta of η Car outside its famous Homunculus nebula.
Methods: We carrie…