Wednesday, September 19, 2007

Additions to the pile: Week of 17 September 2007

Papers of interest in AGU journals last week:

Chapman, S. C., and B. Hnat (2007), Quantifying scaling in the velocity field of the anisotropic turbulent solar wind, GRL 34, L17103.

Eastwood, J. P., S. D. Bale, F. S. Mozer, and A. J. Hull (2007), Contributions to the cross shock electric field at a quasiperpendicular collisionless shock, GRL 34, L17104.

Zong, Q.-G., X.-Z. Zhou, X. Li, P. Song, S. Y. Fu, D. N. Baker, Z. Y. Pu, T. A. Fritz, P. Daly, A. Balogh, and H. Réme (2007), Correction to "Ultralow frequency modulation of energetic particles in the dayside magnetosphere," GRL 34, L17106. The original reference is GRL 34, L12105, 2007.

Horne, R. B., R. M. Thorne, S. A. Glauert, N. P. Meredith, D. Pokhotelov, and O. Santolík (2007), Electron acceleration in the Van Allen radiation belts by fast magnetosonic waves, GRL 34, L17107.

Mende, S. B., V. Angelopoulos, H. U. Frey, S. Harris, E. Donovan, B. Jackel, M. Syrjaesuo, C. T. Russell, and I. Mann (2007), Determination of substorm onset timing and location using the THEMIS ground based observatories, GRL 34, L17108.

Cully, C. M., R. E. Ergun, and A. I. Eriksson (2007), Electrostatic structure around spacecraft in tenuous plasmas, JGR 112, A09211.

Monday, September 10, 2007

Additions to the pile: Week of 10 September 2007

Papers of interest in AGU journals last week:

Sandel, B. R. and M. H. Denton (2007), Global view of refilling the plasmasphere, GRL 34, L17102.

Brain, D. A., R. J. Lillis, D. L. Mitchell, J. S. Halekas, and R. P. Lin (2007), Electron pitch angle distriburions as indicators of magnetic field topology near Mars, JGR 112, A09201.

Newell, P. T., S. Wing, and F. J. Rich (2007), Cusp for high and low merging rates, JGR 112, A09205.

Liang, J., and W. W. Liu (2007), A MHD mechanism for the generation of the meridional current system dirung substorm expansion phase, JGR 112, A09208.

Seyler, C. E., and K. Liu (2007), Particle energization by oblique inertial Alfvén waves in the auroral region, JGR 112, A09302.

Lessard, M. R., W. Lotko, J. LaBelle, W. Peria, C. W. Carlson, F. Creutzberg, and D. D. Wallis (2007), Ground and satellite observations of the evolution of growth phase auroral arcs, JGR 112, A09304.

Thursday, September 6, 2007

Alfvén waves in the solar corona

The current issue of Science (I read the dead tree version) has an article reporting observations of Alfvén waves in the solar corona. The abstract:
Alfvén waves, transverse incompressible magnetic oscillations, have been proposed as a possible mechanism to heat the Sun's corona to millions of degrees by transporting convective energy from the photosphere into the diffuse corona. We report the detection of Alfvén waves in intensity, line-of-sight velocity, and linear polarization images of the solar corona taken using the FeXIII 1074.7-nanometer coronal emission line with the Coronal Multi-Channel Polarimeter (CoMP) instrument at the National Solar Observatory, New Mexico. Ubiquitous upward propagating waves were seen, with phase speeeds of 1 to 4 megameters per second and trajectories consistent with the direction of the magnetic field inferred from the linear polarization measurements. An estimate of the energy carried by the waves that we spatially resolved indicates that they are too weak to heat the solar corona; however, unresolved Alfvén waves may carry sufficient energy.


The reference is S. Tomczyk et al. (2007), Science 317, 1192.

There is substantial in situ evidence, of which Tomczyk et al. appear to be unaware (their paper does not cite any of the magnetospheric literature), that Alfvén waves contribute to heating of ionospheric plasma in the auroral acceleration region (see, e.g., G. Paschmann et al. (2002), Space Science Reviews 103, 1.

Tuesday, September 4, 2007

Additions to the pile: Week of 3 September 2007

Papers of interest in AGU journals in the last week:

Vedin, J., K. Rönnmark, C. Bunescu, and O. Marghitu (2007), Estimating properties of concentrated parallel electric fields from electron velocity distributions, GRL 34, L16107.

Malova, H. V., L. M> Zelenyi, V. Y. Popov, D. C. Delcourt, A. A. Petrukovich, and A. V. Runov (2007), Asymmetric thin current sheets in the Earth's magnetotail, GRL 34, L16108.

Saito, S. and T. Maruyama (2007), Large-scale longitudinal variation in ionospheric height and equatorial spread F occurrences observded by ionosondes, GRL 34, L16109.

Wing, S., J. W. Gjerloev, J. R. Johnson, and R. A. Hoffman (2007), Substorm plasma sheet ion pressure profiles, GRL 34, L16110.

Katoh, Y., and Y. Omura (2007), Correction to "Relativistic particle acceleration in the process of whistler-mode chorus wave generation", GRL 34, L17101. The original reference is GRL 34, L13102.

Heelis, R. A., and W. R. Coley (2007), Variations in the low- and mid-latitude topside ion concentration observed by DMSP during superstorm events, JGR 112, A08310.