Production of cosmogenic isotopes 7Be, 10Be, 14C, 22Na, and 36Cl in the atmosphere: Altitudinal profiles of yield functions

Poluianov, Stepan; Kovaltsov, Gennady A.; Mishev, Alexander; Usoskin, Ilya

doi:10.1002/2016jd025034

Cited by 114 publications

(205 citation statements)

References 72 publications

Supporting

Mentioning

181

Contrasting

Unclassified

Order By: Relevance

“…For example, the mean global-averaged 14 C production rate for the period 1750-1900 is estimated from measurements as 1.75 ± 0.01 atoms cm −2 s −1 (Roth and Joos 2013). The production model Poluianov et al 2016) yields for the same period theoretical production rate 1.71 -1.76 atoms cm −2 s −1 , depending on the solar activity and geomagnetic field reconstructions used, being thus in an excellent agreement with the data.…”

Section: Productionsupporting

confidence: 66%

“…10 Globally-averaged production rate of 14 C as a function of the modulation potential φ and geomagnetic dipole moment M, computed using the yield function by Kovaltsov et al (2012), LIS by Burger et al (2000) and cosmic-ray-modulation model by . Other models (Masarik and Beer 2009;Poluianov et al 2016) yield a similar result state production calculated from the 14 C inventory in the carbon-cycle model (see Sect. 3.2.3) being 1.6 -1.8 atoms cm −2 s −1 for the pre-industrial period (e.g.,Goslar 2001, and references therein).…”

Section: Productionmentioning

confidence: 57%

“…3.2.3) being 1.6 -1.8 atoms cm −2 s −1 for the pre-industrial period (e.g.,Goslar 2001, and references therein). The situation has been resolved recently with a new numerical model Poluianov et al 2016). For example, the mean global-averaged 14 C production rate for the period 1750-1900 is estimated from measurements as 1.75 ± 0.01 atoms cm −2 s −1 (Roth and Joos 2013).…”

Section: Productionmentioning

confidence: 99%

“…The production rate of radiocarbon, Q14 C , can vary as affected by different factors (see, e.g., Damon and Sonett 1991 Poluianov et al 2016), polar neutron monitor ) as well as the energy spectrum of galactic cosmic protons for medium modulation (φ = 550 MV). b The differential production rate for 10 Be and 14 C cosmogenic isotopes, and the differential response function of a polar neutron monitor -Variations of the cosmic-ray flux on a geological timescale due to the changing galactic background (e.g., a nearby supernova explosion or crossing the dense galactic arm).…”

Section: Productionmentioning

confidence: 99%

“…3.1.2), S(P, φ) is the differential energy spectrum of CR (see Sect. 3.1.1) and Y (P) is the differential yield function of cosmogenic isotope production, calculated using a Monte-Carlo simulation of the cosmic-ray-induced atmospheric cascade Poluianov et al 2016). Because of the global nature of the carbon cycle and its long attenuation time, the radiocarbon is globally mixed before the final deposition, and Eq.…”

Section: Productionmentioning

confidence: 99%

See 4 more Smart Citations

A history of solar activity over millennia

Usoskin

2017

Living Rev Sol Phys

381

241

View full text Add to dashboard Cite

Presented here is a review of present knowledge of the long-term behavior of solar activity on a multi-millennial timescale, as reconstructed using the indirect proxy method. The concept of solar activity is discussed along with an overview of the special indices used to quantify different aspects of variable solar activity, with special emphasis upon sunspot number. Over long timescales, quantitative information about past solar activity can only be obtained using a method based upon indirect proxies, such as the cosmogenic isotopes 14 C and 10 Be in natural stratified archives (e.g., tree rings or ice cores). We give an historical overview of the development of the proxy-based method for past solar-activity reconstruction over millennia, as well as a description of the modern state. Special attention is paid to the verification and cross-calibration of reconstructions. It is argued that this method of cosmogenic isotopes makes a solid basis for studies of solar variability in the past on a long timescale (centuries to millennia) during the Holocene. A separate section is devoted to reconstructions of strong solar energetic-particle (SEP) events in the past, that suggest that the present-day average SEP flux is broadly consistent with estimates on longer timescales, and that the occurrence of extra-strong events is unlikely. Finally, the main features of the long-term evolution of solar magnetic activity, including the

show abstract

Section: Productionsupporting

confidence: 66%

Section: Productionmentioning

confidence: 57%

Section: Productionmentioning

confidence: 99%

Section: Productionmentioning

confidence: 99%

Section: Productionmentioning

confidence: 99%

See 3 more Smart Citations

A history of solar activity over millennia

Usoskin

2017

Living Rev Sol Phys

381

241

View full text Add to dashboard Cite

show abstract

Radiocarbon Production by Thunderstorms

Babich

2017

Geophysical Research Letters

View full text Add to dashboard Cite

In view of the neutron flux enhancements observed in thunderstorms, a contribution of thunderstorm neutrons to atmospheric radiocarbon (isotope 14 6 C) production is analyzed in connection with the archaeometry. Herein, estimates of neutron fluence per lightning electromagnetic pulse in regions with severe thunderstorm activity, at which a local rate of the 14 6 C production is comparable to the observed rates, are shown to be consistent with the measured magnitudes of thunderstorm neutron fluence. At present, available observations of atmospheric neutron and parent gamma ray flashes correlated with thunderstorms do not allow making final conclusions about thunderstorm contributions to 14 6 C production. For this, numerous studies of high-energy phenomena in thunderstorms are required, especially in the tropical belt where the thunderstorm activity is especially severe and where the 14 6 C production by galactic cosmic rays is almost independent of the solar activity disturbing the Earth's magnetic field shielding the Earth from cosmic rays. Plain Language Summary Decay of radiocarbon accumulated in fossil biota is widely used in archaeometry. A capture by atmospheric nitrogen nuclei of neutrons, produced by cosmic rays, is causal to the radiocarbon production. In view of that thunderstorms produce neutrons their contribution in the radiocarbon production is analyzed. In regions with severe thunderstorm activity, evaluated neutron numbers per unit area (fluence) per lightning required for a rate of the radiocarbon production by thunderstorms to be comparable to the measured rate magnitudes are consistent with the measured magnitudes of thunderstorm neutron fluence. Available data on thunderstorm neutrons and parent to them gamma ray flashes do not allow making final conclusion about the thunderstorm deposition in the radiocarbon production. For this, numerous observations are required, especially in tropics where the thunderstorm activity is extremely strong and where the radiocarbon production is almost independent of the solar activity disturbing the Earth's magnetic field shielding the Earth from cosmic rays.

show abstract

Neutron Monitors and Cosmogenic Isotopes as Cosmic Ray Energy‐Integration Detectors: Effective Yield Functions, Effective Energy, and Its Dependence on the Local Interstellar Spectrum

et al. 2017

View full text Add to dashboard Cite

The method of assessment of galactic cosmic rays (GCR) variability over different timescales, using energy‐integrating ground‐based detectors such as a neutron monitor and cosmogenic isotopes 10Be and 14C stored in natural archives is revisited here. The effective yield functions for cosmogenic 14C (globally mixed in the atmosphere) and 10Be (realistically deposited in the polar region) are calculated and provided, in a tabulated form, in the supporting information. The effective energy of a detector is redefined so that the variability of the flux of GCR particles at this energy is equal to that of the detector's count rate. The effective energy is found as 11–12 GeV/nucleon for the standard polar neutron monitor, and 6–7 GeV/nucleon and 5.5–6 GeV/nucleon for 14C and 10Be, respectively. New “calibration” relations between the force‐field modulation potentials, based on different models of local interstellar spectra (LIS) are provided. While such relations are typically based on refitting the modeled cosmic ray spectra with a prescribed LIS model, the method introduced here straightforwardly accounts for the exact type of the detector used to assess the spectrum. The relations are given separately for ground‐based neutron monitors and cosmogenic isotopes. This work allows for harmonization of different works related to variability of galactic cosmic ray flux in the vicinity of Earth, on long‐term scale.

show abstract

Production of cosmogenic isotopes ⁷Be, ¹⁰Be, ¹⁴C, ²²Na, and ³⁶Cl in the atmosphere: Altitudinal profiles of yield functions

Cited by 114 publications

References 72 publications

A history of solar activity over millennia

A history of solar activity over millennia

Radiocarbon Production by Thunderstorms

Neutron Monitors and Cosmogenic Isotopes as Cosmic Ray Energy‐Integration Detectors: Effective Yield Functions, Effective Energy, and Its Dependence on the Local Interstellar Spectrum

Contact Info

Product

Resources

About