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Related papers: Reply to "Rapid $^{14}$C excursion at 3372-3371 BC…

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We present the results of full new calculation of radiocarbon 14C production in the Earth atmosphere, using a numerical Monte-Carlo model. We provide, for the first time, a tabulated 14C yield function for the energy of primary cosmic ray…

Atmospheric and Oceanic Physics · Physics 2013-05-23 G. A. Kovaltsov , A. Mishev , I. G. Usoskin

Four significant events of rapid $^{14}$C increase have taken place within the past several thousand years. The physical origin of these rapid increases is still a mystery but must be associated with extremely energetic cosmic processes.…

High Energy Astrophysical Phenomena · Physics 2020-01-08 F. Y. Wang , Xinyu Li , D. O. Chernyshov , C. Y. Hui , G. Q. Zhang , K. S. Cheng

Firestone (2014) asserted evidence for numerous (23) nearby (d<300 pc) supernovae within the Middle and Late Pleistocene. If true, this would have strong implications for the irradiation of the Earth; at this rate, mass extinction level…

Earth and Planetary Astrophysics · Physics 2015-05-27 A. L. Melott , I. G. Usoskin , G. A Kovaltsov , C. M. Laird

The synthesis of isotopes is possible under conditions of power electric discharge in the atmosphere. Knowledge of the radioactive 14C yield under flash conditions (as additional channel of 14C production relative to the main - cosmogenic…

Nuclear Theory · Physics 2021-07-14 V. I. Lyashuk

The flux of cosmic ray muons at the Earth's surface exhibits seasonal variations due to changes in the temperature of the atmosphere affecting the production and decay of mesons in the upper atmosphere. Using 1473 live days of data…

High Energy Physics - Experiment · Physics 2026-01-09 The NOvA Collaboration

Considerable progress has been made in recent years in observations of atmospheric signatures of giant exoplanets, but processes in rocky exoplanets remain largely unknown due to major challenges in observing small planets. Numerous efforts…

Earth and Planetary Astrophysics · Physics 2015-11-23 Brice-Olivier Demory , Michael Gillon , Nikku Madhusudhan , Didier Queloz

Carbon dioxide (CO2) increase has been well documented, and global net primary production is of importance to a variety of ecological topics. Since CO2 increases primary production in laboratory experiments, the global effects of increasing…

Atmospheric and Oceanic Physics · Physics 2018-12-27 Benjamin Helyer , Michael Courtney

A large variation in 14 C around AD 775 has been considered to be caused by one or more solar super-flares within one year. We critically review all known aurora reports from Europe as well as the Near, Middle, and Far East from AD 731 to…

Solar and Stellar Astrophysics · Physics 2015-05-27 Ralph Neuhaeuser , Dagmar L. Neuhaeuser

We report the first detection of the isotopologues 13CCC and C13CC. We used the heterodyne receivers GREAT and upGREAT on board SOFIA to search for the ro-vibrational transitions Q(2) and Q(4) of 13CCC and C13CC at 1.9 THz along the line of…

Rocky planets may acquire a primordial atmosphere by outgassing of volatiles from their magma ocean. The distribution of O between H$_2$O, CO and CO$_2$ in chemical equilibrium subsequently changes significantly with decreasing temperature.…

Earth and Planetary Astrophysics · Physics 2024-09-18 Anders Johansen , Eloi Camprubi , Elishevah van Kooten , Jens Hoeijmakers

In the high-mass star-forming region G35.20-0.74N, small scale (about 800 AU) chemical segregation has been observed in which complex organic molecules containing the CN group are located in a small location. We aim to determine the…

Astrophysics of Galaxies · Physics 2018-08-29 V. Allen , F. F. S. van der Tak , C. Walsh

We present further considerations regarding the strong 14C variation in AD 774/5. For its cause, either a solar super-flare or a short Gamma-Ray Burst were suggested. We show that all kinds of stellar or neutron star flares would be too…

Solar and Stellar Astrophysics · Physics 2015-06-22 Ralph Neuhaeuser , Valeri Hambaryan

Solar Cycle 24 is having a historically long and weak start. Observations of the Fe XIV corona from the Sacramento Peak site of the National Solar Observatory show an abnormal pattern of emission compared to observations of Cycles 21, 22,…

Solar and Stellar Astrophysics · Physics 2012-09-13 Richard Altrock

A commonly-used paradigm to estimate changes in the frequency of past events or the size of populations is to consider the occurrence rate of archaeological/environmental samples found at a site over time. The reliability of such a…

Methodology · Statistics 2025-05-01 Timothy J Heaton , Sara Al-assam , Edouard Bard

The planet-forming disk of HD 142527 is known for its azimuthally asymmetric dust trap, shadows, and spiral arms. We use new ALMA observations to investigate the molecular composition and to determine the ongoing chemical processes and the…

Earth and Planetary Astrophysics · Physics 2026-05-29 Milou Temmink , Ewine F. van Dishoeck , Alice S. Booth , Nienke van der Marel , Myriam Benisty , Michiel R. Hogerheijde

Several researchers have previously identified a severe climatic upheaval in tropical North Africa that began just over 4000 years ago and lasted for about three centuries. The upheaval is known to have occurred shortly after a volcanic…

Geophysics · Physics 2007-05-23 Douglas J. Keenan

We present a millimetre molecular line survey of seven high mass loss rate carbon stars in both the northern and southern skies. A total of 196 emission lines (47 transitions) from 24 molecular species were detected. The observed CO…

Astrophysics · Physics 2009-11-07 P. M. Woods , F. L. Schoeier , L. -A. Nyman , H. Olofsson

Carbon containing molecules in cold molecular clouds show various levels of isotopic fractionation through multiple observations. To understand such effects, we have developed a new gas-grain chemical model with updated 13C fractionation…

Astrophysics of Galaxies · Physics 2020-10-07 Jean-Christophe Loison , Valentine Wakelam , Pierre Gratier , Kevin M. Hickson

In the Letter, interesting evidence is reported to support a central tidal disruption event (TDE) in the known AGN NGC 1097. Considering the motivations of TDE as one probable origination of emission materials of double-peaked broad…

Astrophysics of Galaxies · Physics 2024-02-08 XueGuang Zhang

Using the SIT instrument aboard STEREO we have examined the abundance of the 3He during the ascending phase of solar cycle 24 from January 2010 through December 2012. We report on several cases when 3He-rich solar energetic particle events…

Solar and Stellar Astrophysics · Physics 2013-07-25 R. Bucik , D. E. Innes , U. Mall , A. Korth , G. M. Mason