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Title: Reliability of radio transients detected in the Nasu sky survey

Abstract

This article reports on the reliability of 11 radio transients detected in the Nasu sky survey. We derived false detection rates and evaluated the statistical significance of each transient source. A single source, labeled WJN J1443+3439, was statistically significant at the 10{sup –5} significance level; the other 10 sources were insignificant. On the basis of this single detection, the sky surface density of live radio transients was estimated to be 2{sub −1.9}{sup +9}×10{sup −6} deg{sup −2} at a flux density above 3 Jy and a frequency of 1.42 GHz. Since this result is comparable with other survey results and known transients, WJN J1443+3439 could not be excluded. The sky surface density supported a power-law distribution of source count versus flux density. For transient events, the power-law exponent was approximately –3/2. These results are expected to assist radio variable/transient surveys in next-generation facilities such as the Square Kilometre Array.

Authors:
;  [1]; ; ; ;  [2];  [3];  [4];  [5]
  1. Faculty of Education and Integrated Arts and Sciences, Waseda University, 1-6-1 Nishiwaseda, Shinjuku-ku, Tokyo 169-8050 (Japan)
  2. Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan)
  3. Graduate School of Science and Engineering, Yamaguchi University, 1677-1 Yoshida, Yamaguchi-shi, Yamaguchi 753-8512 (Japan)
  4. Kashima Space Technology Center, National Institute of Information and Communications Technology, 893-1 Hirai, Kashima-shi, Ibaraki 314-8501 (Japan)
  5. Graduate School of Creative Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan)
Publication Date:
OSTI Identifier:
22348190
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 781; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; CATALOGS; COMPARATIVE EVALUATIONS; DENSITY; DETECTION; DISTRIBUTION; FLUX DENSITY; GHZ RANGE; RELIABILITY; SURFACES; TRANSIENTS

Citation Formats

Aoki, Takahiro, Daishido, Tsuneaki, Tanaka, Tai, Nakao, Ryota, Nomura, Naomi, Sugisawa, Kentaro, Niinuma, Kotaro, Takefuji, Kazuhiro, and Kida, Sumiko, E-mail: takahiro_aoki@aoni.waseda.jp. Reliability of radio transients detected in the Nasu sky survey. United States: N. p., 2014. Web. doi:10.1088/0004-637X/781/1/10.
Aoki, Takahiro, Daishido, Tsuneaki, Tanaka, Tai, Nakao, Ryota, Nomura, Naomi, Sugisawa, Kentaro, Niinuma, Kotaro, Takefuji, Kazuhiro, & Kida, Sumiko, E-mail: takahiro_aoki@aoni.waseda.jp. Reliability of radio transients detected in the Nasu sky survey. United States. doi:10.1088/0004-637X/781/1/10.
Aoki, Takahiro, Daishido, Tsuneaki, Tanaka, Tai, Nakao, Ryota, Nomura, Naomi, Sugisawa, Kentaro, Niinuma, Kotaro, Takefuji, Kazuhiro, and Kida, Sumiko, E-mail: takahiro_aoki@aoni.waseda.jp. Mon . "Reliability of radio transients detected in the Nasu sky survey". United States. doi:10.1088/0004-637X/781/1/10.
@article{osti_22348190,
title = {Reliability of radio transients detected in the Nasu sky survey},
author = {Aoki, Takahiro and Daishido, Tsuneaki and Tanaka, Tai and Nakao, Ryota and Nomura, Naomi and Sugisawa, Kentaro and Niinuma, Kotaro and Takefuji, Kazuhiro and Kida, Sumiko, E-mail: takahiro_aoki@aoni.waseda.jp},
abstractNote = {This article reports on the reliability of 11 radio transients detected in the Nasu sky survey. We derived false detection rates and evaluated the statistical significance of each transient source. A single source, labeled WJN J1443+3439, was statistically significant at the 10{sup –5} significance level; the other 10 sources were insignificant. On the basis of this single detection, the sky surface density of live radio transients was estimated to be 2{sub −1.9}{sup +9}×10{sup −6} deg{sup −2} at a flux density above 3 Jy and a frequency of 1.42 GHz. Since this result is comparable with other survey results and known transients, WJN J1443+3439 could not be excluded. The sky surface density supported a power-law distribution of source count versus flux density. For transient events, the power-law exponent was approximately –3/2. These results are expected to assist radio variable/transient surveys in next-generation facilities such as the Square Kilometre Array.},
doi = {10.1088/0004-637X/781/1/10},
journal = {Astrophysical Journal},
number = 1,
volume = 781,
place = {United States},
year = {Mon Jan 20 00:00:00 EST 2014},
month = {Mon Jan 20 00:00:00 EST 2014}
}
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