Context.A new hypothesis is offered to explain the so-called ribbon feature appearing in the all-sky flux maps of energetic neutral atoms presently observed with the IBEX spacecraft, namely that the ribbon is a consequence of inhomogeneities in the local interstellar medium. Aims. The study aims at a detailed presentation of this hypothesis and its implications for the interpretation of ENA measurements with IBEX. Methods. Theoretical considerations regarding three different topics, namely IBEX measurements related to high-energy neutral atoms, Lyman-α observations (made with the Voyager 1 spacecraft) related to low-energy neutral atoms, and astronomical data related to the structure of the interstellar medium, are critically discussed in order to corroborate the hypothesis. Results. It is found that inhomogeneities in the local interstellar medium can explain not only the IBEX ribbon and outer heliospheric Lyman-α observations, but can also account for the interstellar Lyman-α absorption that could only with difficulty be fully attributed to the hydrogen wall in the outer heliosheath if the heliospheric bow shock would indeed be absent. Conclusions. The IBEX observations of the ribbon provide a unique opportunity to learn more about the nature of the interstellar medium surrounding the heliosphere.
The Cosmic Microwave Background (CMB) is taken today as reflecting the thermodynamical state of the universe at these early cosmic times. Based on this assumption and standard cosmological principles meanwhile many fundamental cosmological facts have been deduced from the CMB state which, however, to some surprise reveal that the universe should be dominated by dark energy and dark matter, while for its energy content the usual baryonic matter is nearly negligible. Thus the question which we want to raise in this article is, whether this standard interpretation of the CMB phenomenon is solid and unequivocal enough to support the standard cosmological claims. We shall show, however, that in many details the standard explanation is not straightforward, but allows for important alternatives which seriously should be looked at. Especially arguments for a vanishing cosmic curvature (k = 0) are shown to be weak, and, contrary to the usual claim, the light distance to the recombination horizon is in fact strongly model-biassed. We also show that the CMB dipole which is generally understood as a consequence of a peculiar motion by about 680 km/s with respect to rest system of the CMB can as well, and perhaps even better, be understood as indication of differerent cosmological expansion dynamics seen in an anisotropically expanding universe in different directions of the sky. We also discuss that the power amplitude (i.e. effective Planck temperature) in the dipolar CMB structure depends on wavelength even inverting the dipole maximum orientation in the Wien's branch. In addition unexpected properties of the lowest CMB multipoles could mean that we are at least partly seeing an unquantifyable foreground in the background. Only after its removal the CMB interpretation could at all then, but then on a completely new basis, become a subject of cosmological terms. At the end of this article we shall briefly discuss an alternative explanation of the CMB radiation which helps to better understand the mysterious cosmic photon-to-baryon ratio of about 10 9 .
No abstract
Abstract. We present radio continuum data for 1050 B3 radio sources at 10.6 GHz. These sources constitute the B3-VLA sample which is complete down to 100 mJy at 408 MHz. The aim is the construction of a homogeneous spectral database for a large sample of radio sources, 10 times fainter than the Kühr et al. (1981) sample, in the range 151 MHz to 10.6 GHz. Extended and complex radio sources (53) were mapped; the remaining ones were observed with cross-scans. We detected 99% of the radio sources with a flux density error of about 1 mJy for the fainter ones. The analysis of the quality of the 10.6 GHz data is presented.
The Cosmic Microwave Background (CMB) is taken today as reflecting the thermodynamical state of the universe at these early cosmic times. Based on this assumption and standard cosmological principles meanwhile many fundamental cosmological facts have been deduced from the CMB state which, however, to some surprise reveal that the universe should be dominated by dark energy and dark matter, while for its energy content the usual baryonic matter is nearly negligible. Thus the question which we want to raise in this article is, whether this standard interpretation of the CMB phenomenon is solid and unequivocal enough to support the standard cosmological claims. We shall show, however, that in many details the standard explanation is not straightforward, but allows for important alternatives which seriously should be looked at. Especially arguments for a vanishing cosmic curvature (k = 0) are shown to be weak, and, contrary to the usual claim, the light distance to the recombination horizon is in fact strongly model‐biassed. We also show that the CMB dipole which is generally understood as a consequence of a peculiar motion by about 680 km/s with respect to rest system of the CMB can as well, and perhaps even better, be understood as indication of differerent cosmological expansion dynamics seen in an anisotropically expanding universe in different directions of the sky. We also discuss that the power amplitude (i.e. effective Planck temperature) in the dipolar CMB structure depends on wavelength even inverting the dipole maximum orientation in the Wien's branch. In addition unexpected properties of the lowest CMB multipoles could mean that we are at least partly seeing an unquantifyable foreground in the background. Only after its removal the CMB interpretation could at all then, but then on a completely new basis, become a subject of cosmological terms. At the end of this article we shall briefly discuss an alternative explanation of the CMB radiation which helps to better understand the mysterious cosmic photon‐to‐baryon ratio of about 109.
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