Lyman-alpha emission from nonthermal proton beams

Journal Article · Wed Sep 01 04:00:00 EDT 1976 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/154642· OSTI ID:7337262

Orrall, F Q; Zirker, J B

Nonthermal fast protons penetrating an atmosphere containing neutral hydrogen will produce some nonthermal fast neutrals which will radiate Doppler-shifted photons. The hydrogen line profiles observed from such an atmosphere will thus have nonthermal, partially polarized wings that contain information on the flux, energy spectrum, and direction of the incident proton beam. This paper develops the theory of this effect and applies it to proton beams from impulsive solar flares impacting on the Sun's atmosphere. Calculations of the L..cap alpha.. profile from the region of impact have been made for the Vernazza-Avrett-Loeser solar atmosphere assuming proton energy fluxes and power-law spectra similar to those inferred for the electron beams believed responsible for hard X-ray bursts. The resulting profiles show that the effect should de detectable and that it could serve as a diagnostic for flare protons near their place of origin on the Sun. (AIP)

• Research Organization: Institute for Astronomy, University of Hawaii
• OSTI ID: 7337262
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 208:2; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
BEAMS
BREMSSTRAHLUNG
CHROMOSPHERE
CRYOGENIC FLUIDS
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION SPECTRA
FLUIDS
HYDROGEN
LINE WIDTHS
LYMAN LINES
MATHEMATICAL MODELS
NONMETALS
NUCLEON BEAMS
PARTICLE BEAMS
PROTON BEAMS
RADIATION TRANSPORT
RADIATIONS
SOLAR ACTIVITY
SOLAR ATMOSPHERE
SOLAR FLARES
SPECTRA
STAR MODELS