Nuclear Bursts Produced in the Low Energy Nucleonic Component of the Cosmic Radiations

J. A. Simpson; H. W. Baldwin; R. B. Uretz

doi:10.1103/PhysRev.84.332

Access by Xinjiang University

Nuclear Bursts Produced in the Low Energy Nucleonic Component of the Cosmic Radiations

J. A. Simpson, H. W. Baldwin^*, and R. B. Uretz

Institute for Nuclear Studies, University of Chicago, Chicago, Illinois

^*Deceased.

PDF

Phys. Rev. 84, 332 – Published 15 October, 1951

DOI: https://doi.org/10.1103/PhysRev.84.332

Abstract

The production rate of low energy nuclear bursts or stars has been measured as a function of altitude and geomagnetic lactitude, $λ$ , at 0°, 40° N and 52° N through 65° N. The measurements were obtained in aircraft using fast electron collection pulse chambers. Exponential absorption paths, $L_{b} (λ)$ , for the nuclear burst or star producing radiation below ∼200 ${g - c m}^{- 2}$ are $L_{b} (0 °) = 214 \pm 7$ ; $L_{b} (40 °) = 174 \pm 6$ ; $L_{b} (>~ 52 °) = 164 \pm 14$ ${g - c m}^{- 2}$ . At an atmospheric depth of 312 ${g - c m}^{- 2}$ the latitude factor of increase from 0° to 52°N is 3.11±0.15 on undisturbed days. The disintegration product fast neutrons have a latitude factor of 3.30±0.05 under the same conditions. Integral pulse-height distributions of nuclear bursts both at 0° and 52° are represented by $N_{b} = A V^{- 2.5 \pm 0.1}$ , where $N_{b}$ is the number of burst pulses > bias energy $V$ .

A similar study of local showers produced in lead over the chambers at 0° and 52° shows a latitude factor of <1.1 and an exponential absorption of the shower producing radiations at all latitudes of 134±7 ${g - c m}^{- 2}$ . The integral pulse-height distribution for showers was $N_{s} = B V^{- 2.0 \pm 0.15}$ .

From the measurements it is concluded that (a) the small stars are produced in atoms by inelastic collisions and knock-on processes by nucleons and the average number rather than the average energy of the stars produced by high energy nucleons increases with increasing primary nucleon energy, (b) the small nuclear bursts are in equilibrium with the fast neutron production in the atmosphere below ∼200 ${g - c m}^{- 2}$ and these small bursts account for almost the entire fast neutron intensity in the atmosphere, (c) these small stars and neutrons represent the low energy limit of the nucleonic component, (d) the production rate of small nuclear stars is not strongly dependent on primary nucleon momentum above ∼4 Bev/c.

References (14)

J. A. Simpson, Phys. Rev. 83, 1175 (1951) 73, 1389 (1948)
Bridge, Hazen, Rossi, and Williams, Phys. Rev. 74, 1083 (1948) H. Bridge and B. Rossi, 75, 810 (1949) 71, 379 (1947)
McMahon, Rossi, and Burditt, Phys. Rev. 80, 157 (1950)
J. A. Simpson and R. B. Uretz, Phys. Rev. 76, 569 (1949) Proc. Echo Lake Conf. 1949 J. A. Simpson and E. Hungerford, Phys. Rev. 77, 847 (1950)
Morand, Beets, and Winand, Compt. rend. 229, 227 (1949) ibid.231, 851 (1950) S. Lattimore, Phil. Mag. 41, 961 (1950)
M. Schein and J. J. Lord, Phys. Rev. 73, 189 (1948) Salant, Hornbostel, Fisk, and Smith, 79, 184 (1950) J. J. Lord, 81, 901 (1951)
Omitted endnote
Montgomery, Montgomery, and Northrup, Phys. Rev. 79, 293 (1950)
Bernardini, Cortini, and Manfredini, Phys. Rev. 76, 1792 (1949) ibid.79, 952 (1950)
E. P. George and A. C. Jason, Cosmic Radiations, Colston Papers (Butterworths Science Publications, London, 1949)
G. N. Whyte, Phys. Rev. 82, 204 (1951)
H. Carmichael, Phys. Rev. 74, 1667 (1948)
C. G. Montgomery and D. D. Montgomery, Phys. Rev. 76, 1482 (1949)
Barton, George, and Jason, Proc. Phys. Soc. (London) A64, 175 (1951)

[c1] J. A. Simpson, Phys. Rev. 83, 1175 (1951) 73, 1389 (1948)

[c2] Bridge, Hazen, Rossi, and Williams, Phys. Rev. 74, 1083 (1948) H. Bridge and B. Rossi, 75, 810 (1949) 71, 379 (1947)

[c3] McMahon, Rossi, and Burditt, Phys. Rev. 80, 157 (1950)

[c4] J. A. Simpson and R. B. Uretz, Phys. Rev. 76, 569 (1949) Proc. Echo Lake Conf. 1949 J. A. Simpson and E. Hungerford, Phys. Rev. 77, 847 (1950)

[c5] Morand, Beets, and Winand, Compt. rend. 229, 227 (1949) ibid.231, 851 (1950) S. Lattimore, Phil. Mag. 41, 961 (1950)

[c6] M. Schein and J. J. Lord, Phys. Rev. 73, 189 (1948) Salant, Hornbostel, Fisk, and Smith, 79, 184 (1950) J. J. Lord, 81, 901 (1951)

[c7] Omitted endnote

[c8] Montgomery, Montgomery, and Northrup, Phys. Rev. 79, 293 (1950)

[c9] Bernardini, Cortini, and Manfredini, Phys. Rev. 76, 1792 (1949) ibid.79, 952 (1950)

[c10] E. P. George and A. C. Jason, Cosmic Radiations, Colston Papers (Butterworths Science Publications, London, 1949)

[c11] G. N. Whyte, Phys. Rev. 82, 204 (1951)

[c12] H. Carmichael, Phys. Rev. 74, 1667 (1948)

[c13] C. G. Montgomery and D. D. Montgomery, Phys. Rev. 76, 1482 (1949)

[c14] Barton, George, and Jason, Proc. Phys. Soc. (London) A64, 175 (1951)

Physical Review Journals Archive

Export citation

Export citation

Nuclear Bursts Produced in the Low Energy Nucleonic Component of the Cosmic Radiations

Abstract

References (14)

Outline

Information

Filter

Filter

Article Lookup

Enter a citation