scholarly journals Nuclear Processes in Dark Interstellar Matter of H(0) Decrease the Hope of Migrating to Exoplanets

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Leif Holmlid
Keyword(s):  
Interstellar Space ◽  
Relativistic Velocity ◽  
Interstellar Matter ◽  
Space Travel ◽  
Red Emission ◽  
Low Intensity ◽  
High Particle ◽  
Astrophysical Journal ◽  
Extended Red Emission ◽  
Nuclear Processes

It is still generally assumed that interstellar travel will be possible after purely technical development and thus that mankind can move to some suitable exoplanet when needed. However, recent research indicates this not to be the case, since interstellar space is filled with enough ultradense hydrogen H(0) as stable condensed dark matter (Holmlid, Astrophysical Journal 2018) to make interstellar space travel at the required and technically feasible relativistic velocities (Holmlid et al, Acta Astronautica 2020) almost impossible. H(0) can be observed to exist in space from the so-called extended red emission (ERE) features observed in space. A recent review (Holmlid et al., Physica Scripta 2019) describes the properties of H(0). H(0) gives nuclear processes emitting kaons and other particles, with kinetic energies even above 100 MeV after induction for example by fast particle (spaceship) impact. These high particle energies give radiative temperatures of 12000 K in collisions against a solid surface and will rapidly destroy any spaceship structure moving into the H(0) clouds at relativistic velocity. The importance of preserving our ecosystem is pointed out, since travel to suitable exoplanets may be impossible. The possibilities of instead clearing interstellar space from H(0) are discussed, eventually providing tunnels suitable for relativistic interstellar transport. Finding regions with low intensity of ERE could even be a way to identify space-cleaning activities and thus to locate earlier space-travelling civilizations.

scholarly journals Blue Luminescence and Extended Red Emission: Possible Connections to the Diffuse Interstellar Bands

2013 ◽  
Vol 9 (S297) ◽  
pp. 173-179 ◽  
Author(s):  
A. N. Witt
Keyword(s):  
Quantum Efficiency ◽  
Spectral Characteristics ◽  
Emission Feature ◽  
Single Step ◽  
Blue Luminescence ◽  
Interstellar Space ◽  
H Ii Regions ◽  
High Quantum Efficiency ◽  
Red Emission ◽  
Extended Red Emission

AbstractBlue luminescence (BL) and extended red emission (ERE) are observed as diffuse, optical-wavelength emissions in interstellar space, resulting from photoluminescence by ultraviolet(UV)-illuminated interstellar grains. Faintness and the challenge of separating the BL and ERE from the frequently much brighter dust-scattered continuum present major observational hurdles, which have permitted only slow progress in testing the numerous models that have been advanced to explain these two phenomena. Both the ERE, peaking near 680 nm (FWHM ~ 60 - 120 nm) and the BL, asymmetrically peaking at ~ 378 nm (FWHM ~ 45 nm), were first discovered in the Red Rectangle nebula. Subsequently, ERE and BL have been observed in other reflection nebulae, and in the case of the ERE, in carbon-rich planetary nebulae, H II regions, high-latitude cirrus clouds, the galactic diffuse ISM, and in external galaxies. BL exhibits a close spatial and intensity correlation with emission in the aromatic emission feature at 3.3 micron, most likely arising from small, neutral polycyclic aromatic hydrocarbon (PAH) molecules. The spectral characteristics of the BL also agree with those of fluorescence by PAH molecules with 13 to 19 carbon atoms. The BL phenomenon is thus most readily understood as the optical fluorescence of small, UV-excited aromatic molecules. The ERE, by contrast, though co-existent with mid-IR PAH emissions, does not correlate with emissions from either neutral or ionized PAHs. Instead, the spatial ERE morphology appears to be strictly governed by the density of far-UV (E ≥ 10.5 eV) photons, which are required for the ERE excitation. The most restrictive observational constraint for the ERE process is its exceptionally high quantum efficiency. If the ERE results from photo-excitation of a nano-particle carrier by photons with E ≥ 10.5 eV in a single-step process, the quantum efficiency exceeds 100%. Such a process, in which one to three low-energy optical photons may be emitted following a single far-UV excitation, is possible in highly isolated small clusters, e.g. small, dehydrogenated carbon clusters with about 20 to 28 carbon atoms. A possible connection between the ERE carriers and the carriers of DIBs may exist in that both are ubiquitous throughout the diffuse interstellar medium and both have an abundance of low-lying electronic levels with E ≤ 2.3 eV above the ground state.

scholarly journals Are the Carriers of Diffuse Interstellar Bands and Extended Red Emission the same?

2020 ◽  
Author(s):  
Thomas S-Y Lai ◽  
Adolf N Witt ◽  
Carlos Alvarez ◽  
Jan Cami
Keyword(s):  
Molecular Ions ◽  
Ionization Front ◽  
Stellar Spectrum ◽  
Red Emission ◽  
Large Molecules ◽  
Radiation Fields ◽  
Diffuse Interstellar Bands ◽  
Vibrational Levels ◽  
Extended Red Emission ◽  
Photodissociation Region

Abstract We report the first spectroscopic observations of a background star seen through the region between the ionization front and the dissociation front of the nebula IC 63. This photodissociation region (PDR) exhibits intense extended red emission (ERE) attributed to fluorescence by large molecules/ions. We detected strong diffuse interstellar bands (DIB) in the stellar spectrum, including an exceptionally strong and broad DIB at λ4428. The detection of strong DIBs in association with ERE could be consistent with the suggestion that the carriers of DIBs and ERE are identical. The likely ERE process is recurrent fluorescence, enabled by inverse internal conversions from highly excited vibrational levels of the ground state to low-lying electronic states with subsequent transitions to ground. This provides a path to rapid radiative cooling for molecules/molecular ions, greatly enhancing their ability to survive in a strongly irradiated environment. The ratio of the equivalent widths (EW) of DIBs λ5797 and λ5780 in IC 63 is the same as that observed in the low-density interstellar medium with UV interstellar radiation fields (ISRF) weaker by at least two orders of magnitude. This falsifies suggestions that the ratio of these two DIBs can serve as a measure of the UV strength of the ISRF. Observations of the nebular spectrum of the PDR of IC 63 at locations immediately adjacent to where DIBs were detected failed to reveal any presence of sharp emission features seen in the spectrum of the Red Rectangle nebula. This casts doubts upon proposals that the carriers of these features are the same as those of DIBs seen at slightly shorter wavelengths.

The extended red emission filaments in NGC 2023

1989 ◽  
Vol 347 ◽  
pp. L25 ◽  
Author(s):  
Adolf N. Witt ◽  
David F. Malin
Keyword(s):  
Red Emission ◽  
Extended Red Emission
Sign in / Sign up

Export Citation Format

Share Document