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Title: Initial speed of knots in the plasma tail of C/2013 R1(Lovejoy)

Abstract

We report short-time variations in the plasma tail of C/2013 R1(Lovejoy). A series of short (2–3 minutes) exposure images with the 8.2 m Subaru telescope shows faint details of filaments and their motions over a 24 minute observing duration. We identified rapid movements of two knots in the plasma tail near the nucleus (∼3×10{sup 5} km). Their speeds are 20 and 25 km s{sup −1} along the tail and 3.8 and 2.2 km s{sup −1} across it, respectively. These measurements set a constraint on an acceleration model of plasma tail and knots as they set the initial speed just after their formation. We also found a rapid narrowing of the tail. After correcting the motion along the tail, the narrowing speed is estimated to be ∼8 km s{sup −1}. These rapid motions suggest the need for high time-resolution studies of comet plasma tails with a large telescope.

Authors:
; ; ;  [1];  [2];  [3]
+ Show Author Affiliations
  1. National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan)
  2. Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11794-3800 (United States)
  3. Subaru Telescope, 650 North A’ohoku Place, Hilo, HI 96720 (United States)
Publication Date:
OSTI Identifier:
22342089
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (New York, N.Y. Online); Journal Volume: 149; Journal Issue: 3; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; COMETS; FILAMENTS; IMAGES; LIMITING VALUES; PLASMA; SOLAR WIND; TELESCOPES; TIME RESOLUTION; VELOCITY

Citation Formats

Yagi, Masafumi, Furusho, Reiko, Terai, Tsuyoshi, Watanabe, Jun-Ichi, Koda, Jin, and Fujiwara, Hideaki, E-mail: YAGI.Masafumi@nao.ac.jp. Initial speed of knots in the plasma tail of C/2013 R1(Lovejoy). United States: N. p., 2015. Web. doi:10.1088/0004-6256/149/3/97.
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Yagi, Masafumi, Furusho, Reiko, Terai, Tsuyoshi, Watanabe, Jun-Ichi, Koda, Jin, & Fujiwara, Hideaki, E-mail: YAGI.Masafumi@nao.ac.jp. Initial speed of knots in the plasma tail of C/2013 R1(Lovejoy). United States. doi:10.1088/0004-6256/149/3/97.
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Yagi, Masafumi, Furusho, Reiko, Terai, Tsuyoshi, Watanabe, Jun-Ichi, Koda, Jin, and Fujiwara, Hideaki, E-mail: YAGI.Masafumi@nao.ac.jp. Sun . "Initial speed of knots in the plasma tail of C/2013 R1(Lovejoy)". United States. doi:10.1088/0004-6256/149/3/97.
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@article{osti_22342089,
title = {Initial speed of knots in the plasma tail of C/2013 R1(Lovejoy)},
author = {Yagi, Masafumi and Furusho, Reiko and Terai, Tsuyoshi and Watanabe, Jun-Ichi and Koda, Jin and Fujiwara, Hideaki, E-mail: YAGI.Masafumi@nao.ac.jp},
abstractNote = {We report short-time variations in the plasma tail of C/2013 R1(Lovejoy). A series of short (2–3 minutes) exposure images with the 8.2 m Subaru telescope shows faint details of filaments and their motions over a 24 minute observing duration. We identified rapid movements of two knots in the plasma tail near the nucleus (∼3×10{sup 5} km). Their speeds are 20 and 25 km s{sup −1} along the tail and 3.8 and 2.2 km s{sup −1} across it, respectively. These measurements set a constraint on an acceleration model of plasma tail and knots as they set the initial speed just after their formation. We also found a rapid narrowing of the tail. After correcting the motion along the tail, the narrowing speed is estimated to be ∼8 km s{sup −1}. These rapid motions suggest the need for high time-resolution studies of comet plasma tails with a large telescope.},
doi = {10.1088/0004-6256/149/3/97},
journal = {Astronomical Journal (New York, N.Y. Online)},
number = 3,
volume = 149,
place = {United States},
year = {Sun Mar 01 00:00:00 EST 2015},
month = {Sun Mar 01 00:00:00 EST 2015}
}
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Journal Article:
DOI:  10.1088/0004-6256/149/3/97
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