Amplification of electrostatic ion-cyclotron waves in a plasma with magnetic-field-aligned ion flow shear and no electron current

نویسندگان

  • Su-Hyun Kim
  • Erick Agrimson
  • Michael J. Miller
  • Robert L. Merlino
  • Gurudas I. Ganguli
چکیده

Experimental demonstration of the amplification of electrostatic ion-cyclotron waves in a plasma with parallel ion flow shear but no magnetic-field-aligned electron current is presented. Waves with frequencies near the ion gyrofrequency and multiple harmonics launched from an antenna are observed to grow in amplitude in a region of ion flow shear. Amplification of multiple cyclotron harmonics was observed when a broadband (white noise) signal was applied to the launching antenna. Implications of these results for plasma wave excitation in the Earth’s auroral region are discussed. © 2004 American Institute of Physics. [DOI: 10.1063/1.1780531]

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Renormalized theory of the ion cyclotron turbulence in magnetic field–aligned plasma shear flow

The analytical treatment of nonlinear evolution of the shear-flow-modified current driven ion cyclotron instability and shear-flow-driven ion cyclotron kinetic instabilities of magnetic field–aligned plasma shear flow is presented. Analysis is performed on the base of the nonlinear dispersion equation, which accounts for a new combined effect of plasma turbulence and shear flow. It consists in ...

متن کامل

Electrostatic Ion-Cyclotron Instabilities Modified by the Parallel and Perpendicular Plasma Flow Velocity Shears

The external and independent control of plasma flow velocity shears parallel and perpendicular to magnetic field lines is realized using segmented collisionless-plasma sources. Electrostatic ion-cyclotron instabilities are observed to be suppressed by the perpendicular flow velocity shears, the suppression physics of which is found to be distinguished into two aspects. On the other hand, the pa...

متن کامل

Shear Alfvén waves in a magnetic beach and the roles of electron and ion damping

Experiments are performed in the Large Plasma Device ~LaPD! @Gekelman et al., Rev. Sci. Instrum. 62, 2875 ~1991!# at the University of California, Los Angeles to study the propagation of the shear Alfvén wave in a parallel gradient of the background magnetic field. The waves are excited by modulating a field-aligned electron current drawn to a disk antenna with a radius on the order of the elec...

متن کامل

Laboratory studies of field-aligned density striations and their relationship to auroral processes*

Magnetic field-aligned structures in current, density, and temperature are common features of the auroral ionospheric plasma. These structures both generate and transform low frequency waves in the plasma. The results of laboratory studies of two processes involving magnetic field-aligned density depletions ~striations! that play a role in auroral plasma dynamics are presented. The first proces...

متن کامل

Generation of “spiky” potential structures associated with multiharmonic electrostatic ion-cyclotron waves

The production of coherent, “spiky” electrostatic potential structures, similar to the spiky electric-field structures that have been observed in the Earth’s auroral region, is investigated in a magnetized Q machine plasma. These structures are associated with coherent multiharmonic electrostatic ion-cyclotron EIC waves in a current-free plasma having a localized region of ion flow shear ion fl...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2004