Search Publications
Water and Martian habitability: Results of an integrative study of water related processes on Mars in context with an interdisciplinary Helmholtz research alliance “Planetary Evolution and Life”
Jaumann, R.; Tirsch, D.; Hiesinger, H. +7 more
A study in context with the Helmholtz Alliance 'Planetary Evolution and Life' focused on the (temporary) existence of liquid water, and the likelihood that Mars has been or even is a habitable planet. Both geomorphological and mineralogical evidence point to the episodic availability of liquid water at the surface of Mars, and physical modeling an…
Weighted statistical parameters for irregularly sampled time series
Rimoldini, Lorenzo
Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time and corrupt measurements, for example, or inherent to the scanning law of satellites like Hipparcos and the forthcoming Gaia. Irregular sampling often causes clumps of measur…
Technique for measuring and correcting the Taylor microscale
Dasso, S.; Matthaeus, W. H.; Smith, C. W. +3 more
We discuss and develop methods to estimate and refine measurements of the Taylor microscale from discrete data sets. To study how well a method works, we construct a time series of discrete data with a known power spectrum and Taylor scale, but with various truncations of the resolution that eliminate higher frequencies in a controlled fashion. We…
Effects of mass varying neutrinos on cosmological parameters as determined from the cosmic microwave background
Ghalsasi, Akshay; Nelson, Ann E.
In models with a light scalar field (the "acceleron") coupled to neutrinos, neutrino masses depend on neutrino density. The resulting coupled system of mass varying neutrinos (MaVaNs) and the acceleron can act as a negative pressure fluid and is a candidate for dark energy [R. Fardon et al. J. Cosmol. Astropart. Phys. 10 (2004) 005]. MaVaNs also a…
Quantum collapse as a source of the seeds of cosmic structure during the radiation era
Landau, Susana J.; León, Gabriel; Piccirilli, María Pía
The emergence of the seeds of cosmic structure, from a perfect isotropic and homogeneous Universe, has not been clearly explained by the standard version of inflationary models as the dynamics involved preserve the homogeneity and isotropy at all times. A proposal that attempts to deal with this problem, by introducing "the self-induced collapse h…
An Atlas of Far-ultraviolet Spectra of the Zeta Aurigae Binary 31 Cygni with Line Identifications
Bennett, Philip D.; Hagen Bauer, Wendy
The ζ Aurigae system 31 Cygni (K4 Ib + B4 V) was observed by the FUSE satellite during total eclipse and at three phases during chromospheric eclipse. We present the coadded, calibrated spectra and atlases with line identifications. During total eclipse, emission from high ionization states (e.g., Fe III and Cr III) shows asymmetric profiles redsh…
A close examination of cosmic microwave background mirror-parity after Planck
Kovetz, Ely D.; Ben-David, Assaf
Previous claims of significant evidence for mirror-parity in the large-scale cosmic microwave background (CMB) data from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment have been recently echoed in the first study of isotropy and statistics of CMB data from Planck. We revisit these claims with a careful analysis of the latest data avail…
Lyman edges in supermassive black hole binaries.
Generozov, A.; Haiman, Z.
We propose a new spectral signature for supermassive black hole binaries (SMBHBs) with circumbinary gas discs: a sharp drop in flux bluewards of the Lyman limit. A prominent edge is produced if the gas dominating the emission in the Lyman continuum region of the spectrum is sufficiently cold (T ≲ 20 000 K) to contain significant neutral hydrogen. …
XMM-Newton observations of the low-luminosity cataclysmic variable V405 Pegasi
Granzer, T.; Pires, A. M.; Thorstensen, J. R. +4 more
Context. V405 Peg is a low-luminosity cataclysmic variable (CV) that was identified as the optical counterpart of the bright, high-latitude ROSAT all-sky survey source RBS1955. The system was suspected to belong to a largely undiscovered population of hibernating CVs. Despite intensive optical follow-up its subclass however remained undetermined. …
Tracing Recent Star Formation of Red Early-type Galaxies out to z ~ 1
Im, Myungshin; Lee, Jong Chul; Hwang, Ho Seong +3 more
We study the mid-infrared (IR) excess emission of early-type galaxies (ETGs) on the red sequence at z < 1 using a spectroscopic sample of galaxies in the fields of Great Observatories Origins Deep Survey (GOODS). In the mass-limited sample of 1025 galaxies with M star > 1010.5 M ⊙ and 0.4 < z < 1.05, we…