Structure of the wake field in plasma channels

Journal Article · Tue Apr 01 04:00:00 EST 1997 · Physics of Plasmas

DOI:https://doi.org/10.1063/1.872186· OSTI ID:530920

Andreev, N E ^[1]; Gorbunov, L M ^[2]; Kirsanov, V I ^[1]; Nakajima, K; Ogata, A ^[3]

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1. High Energy Density Research Center, Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russia)
2. P.N. Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russia)
3. National Laboratory for High Energy Physics, Tsukuba, Ibaraki (Japan)

An equation is derived that describes the linear response of an underdense inhomogeneous plasma [{omega}{sub 0}{gt}{omega}{sub p}({bold r}), where {omega}{sub 0} and {omega}{sub p}({bold r}) are the laser-carrier and plasma frequencies, respectively] during the propagation of a laser pulse along the axis of a plasma channel with a characteristic width R{sub ch}. For a wide channel, i.e., when R{sub ch}/{lambda}{sub p0}{gt}1 (where {lambda}{sub p0}=2{pi}c/{omega}{sub p0} is the wavelength of the excited plasma wave and {omega}{sub p0} is the plasma frequency at the channel axis), the structure of the wake field is studied analytically. It is shown that this structure changes with the distance from the trailing edge of the pulse. As a result, at a certain distance behind the pulse, the fraction of the plasma wave period in which the simultaneous focusing and acceleration of electrons are possible increases by a factor of 2. For a narrow channel (R{sub ch}/{lambda}{sub p0}{lt}1), the structure of the wake field is studied numerically and it is shown that, in this case, the doubling of the phase interval of the wave where the simultaneous focusing and acceleration of electrons are possible also occurs; but, in contrast to a wide channel, a rapid reconstruction of the wake occurs, so that the amplitude of the axial (accelerating) field in the wake decreases while the radial (focusing) field increases with the distance from the pulse trailing edge. The numerical modeling of the laser pulse (90 fs, 2 TW) guiding and the excitation of plasma waves in a narrow plasma channel is carried out and the possibility of reaching GeV energies of accelerated electrons in an experiment is discussed. {copyright} {ital 1997 American Institute of Physics.}

• OSTI ID: 530920
• Journal Information: Physics of Plasmas, Journal Name: Physics of Plasmas Journal Issue: 4 Vol. 4; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
DISPERSION RELATIONS
INHOMOGENEOUS PLASMA
LASER-PRODUCED PLASMA
PLASMA WAVES
VISIBLE RADIATION
WAVE PROPAGATION