STATISTICAL STUDY OF CHROMOSPHERIC ANEMONE JETS OBSERVED WITH HINODE/SOT

Journal Article · Sun Apr 10 00:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/731/1/43· OSTI ID:21574759

Nishizuka, N ^[1]; Nakamura, T; Kawate, T; Singh, K A. P.; Shibata, K ^[2]

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1. Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa 229-8510 (Japan)
2. Kwasan and Hida observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan)

The Solar Optical Telescope on board Hinode has revealed numerous tiny jets in all regions of the chromosphere outside of sunspots. A typical chromospheric anemone jet has a cusp-shaped structure and bright footpoint, similar to the shape of an X-ray anemone jet observed previously with the Soft X-ray Telescope on board Yohkoh. The similarity in the shapes of chromospheric and X-ray anemone jets suggests that chromospheric anemone jets are produced as a result of the magnetic reconnection between a small bipole (perhaps a tiny emerging flux) and a pre-existing uniform magnetic field in the lower chromosphere. We examine various chromospheric anemone jets in the solar active region near the solar limb and study the typical features (e.g., length, width, lifetime, and velocity) of the chromospheric anemone jets. Statistical studies show that chromospheric anemone jets have: (1) a typical length {approx}1.0-4.0 Mm, (2) a width {approx}100-400 km, (3) a lifetime {approx}100-500 s, and (4) a velocity {approx}5-20 km s{sup -1}. The velocity of the chromospheric anemone jets is comparable to the local Alfven speed in the lower solar chromosphere ({approx}10 km s{sup -1}). The histograms of chromospheric anemone jets near the limb and near the disk center show similar averages and shapes of distributions, suggesting that the characteristic behavior of chromospheric anemone jets is independent of whether they are observed on the disk or at the limb. The observed relationship between the velocity and length of chromospheric anemone jets shows that the jets do not follow ballistic motion but are more likely accelerated by some other mechanism. This is consistent with numerical simulations of chromospheric anemone jets.

• OSTI ID: 21574759
• Journal Information: Astrophysical Journal, Vol. 731, Issue 1; Other Information: DOI: 10.1088/0004-637X/731/1/43; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
CHROMOSPHERE
JETS
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
SOLAR ACTIVITY
VELOCITY
X RADIATION
ATMOSPHERES
ELECTROMAGNETIC RADIATION
FLUID MECHANICS
HYDRODYNAMICS
IONIZING RADIATIONS
MECHANICS
RADIATIONS
SOLAR ATMOSPHERE
STELLAR ACTIVITY
STELLAR ATMOSPHERES