Photonuclear reaction data, 1973

Fuller, E. G.; Gerstenberg, H.M.; Molen, H. Vander; Dunn, T.C.

doi:10.6028/nbs.sp.380

Cited by 15 publications

(8 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…where A is the mass number, Z is the nuclear charge, N = A − Z, M is the nucleon mass and ǫ is the photon energy in the rest system of the nucleus. The TRK sum rule is not exact, however, owing to the presence of nuclear exchange forces (Feenberg 1936), as can be seen in Table 1 of PSB (which is based on the data tabulations of Fuller, Gerstenberg, Vander Molen, and Dunn (1973) and related material supplied by E. Fuller.…”

Section: Cross Sectionsmentioning

confidence: 99%

Photodisintegration of Ultra–High‐Energy Cosmic Rays: A New Determination

Salamon

1999

ApJ

254

255

View full text Add to dashboard Cite

We present the results of a new calculation of the photodisintegration of ultraÈhigh-energy cosmic-ray (UHCR) nuclei in intergalactic space. The critical interactions for energy loss and photodisintegration of UHCR nuclei occur with photons of the 2.73 K cosmic background radiation (CBR) and with photons of the IR background radiation (IBR). We have reexamined this problem, making use of a new determination of the IBR based on empirical data primarily from IRAS galaxies, which is consistent with direct measurements and upper limits from TeV c-ray observations. We have also improved the calculation by including the speciÐc threshold energies for the various photodisintegration interactions in our Monte Carlo calculation. With the new smaller IBR Ñux, the steepness of the Wien side of the now relatively more important CBR makes their inclusion essential for more accurate results. Our results indicate a signiÐcant increase in the propagation time of UHCR nuclei of a given energy over previous results. We discuss the possible signiÐcance of this for UHCR origin theory. Subject headings : cosmic microwave background È cosmic rays È di †use radiation È intergalactic medium

show abstract

Section: Cross Sectionsmentioning

confidence: 99%

Photodisintegration of Ultra–High‐Energy Cosmic Rays: A New Determination

Salamon

1999

ApJ

254

255

View full text Add to dashboard Cite

show abstract

“…In the past half century, the giant dipole resonance (GDR) has been investigated both experimentally and theoretically via photonuclear reactions by many researchers [1,2]. Nowadays, more precise measurements of photoneutron reactions near the neutron threshold (S n ) are performed by using quasimonochromatic γ rays [3][4][5][6].…”

Section: Introductionmentioning

confidence: 99%

Dipole strength inSe80forsprocess and nuclear transmutation ofSe79

et al. 2016

View full text Add to dashboard Cite

The dipole strength distribution of 80 Se was studied in a photon-scattering experiment by using bremsstrahlung produced with an electron beam of energy 11.5 MeV at the linear accelerator ELBE. We identified 180 γ transitions up to an energy of 9.6 MeV, and analyzed the strength in the quasicontinuum of the spectrum. Simulations of statistical γ -ray cascades were performed to estimate intensities of inelastic transitions and to correct the intensities of the ground-state transitions for their branching ratios. The photoabsorption cross section below the neutron-separation energy derived in this way was combined with the photoabsorption cross section obtained from an earlier (γ,n) experiment and used as an input for the calculation of 79 Se(n,γ ) reaction rates on the basis of the statistical reaction model.

show abstract

“…The Greisen-Zatsepin-Kuzmin (GZK) horizon of helium [1,2] is a key parameter in ascertaining the contribution of ultrahigh-energy (E 10 10 GeV) cosmic rays (UHECRs) with directional pointing to nearby sources. Numerical [3,4] and analytical [5] estimates of this parameter, as well as Monte Carlo simulation codes of UHECR propagation [6][7][8][9][10][11] are customarily based on fits [12][13][14][15] to cross-section measurements from the sixties [16][17][18][19][20][21], which do not allow a precise description of the giant dipole resonance (GDR) near threshold.…”

Section: Introductionmentioning

confidence: 99%

Photo-disintegration of He4 on the cosmic microwave background is less severe than earlier thought

2018

View full text Add to dashboard Cite

We thoroughly study the photo-disintegration of 4 He on the cosmic microwave background using the most recent cross-section data both from the inclusive measurement observing the analog of the giant dipole resonance in 4 He through the charge-exchange spin-flip 4 He ( 7 Li, 7 Be) reaction and from measurements of exclusive two-body and three-body processes: 4 He (γ, p) 3 H, 4 He (γ, n) 3 He, and 4 He (γ, pn) 2 H. We show that the present-day (redshift z = 0) mean free path of ultra-relativistic (Lorentz factor ∼ 10 10 ) helium nuclei increases by more that 15% with respect to previous estimates adopted as benchmarks for Monte Carlo simulation codes of ultrahigh-energy cosmic ray propagation. This implies that the physical survival probability of 4 He nuclei would be larger than predicted by existing event generators. For example, for E ∼ 10 10.8 GeV and a propagation distance of 3.5 Mpc, the 4 He intensity would be 35% larger than the output of CRPropa 3 program and 42% larger than the output of SimProp v2r4 program. We provide new parametrizations for the two-body and three-body photodisintegration cross-sections of 4 He, 3 He, tritium, and deuterium.

show abstract

Photonuclear reaction data, 1973

Cited by 15 publications

References 0 publications

Photodisintegration of Ultra–High‐Energy Cosmic Rays: A New Determination

Photodisintegration of Ultra–High‐Energy Cosmic Rays: A New Determination

Dipole strength inSe80forsprocess and nuclear transmutation ofSe79

Photo-disintegration of He4 on the cosmic microwave background is less severe than earlier thought

Contact Info

Product

Resources

About