• En-Wei Liang

      Articles written in Journal of Astrophysics and Astronomy

    • Is GRB 100418A a Cosmic Twin of GRB 060614?

      Lan-Wei Jia Hou-Jun Lü Shu-Jin Hou En-Wei Liang

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      GRB 100418A is a long burst at 𝑧 = 0.624 without detection of associated supernova (SN).We present a detailed analysis on this event and discuss possible origins of its multi-wavelength emission. The temporal features of this event is similar to GRB 060614, a well-known nearby long GRB without SN association (possibly a Type I GRB), indicating that the two events may be cosmic twins. However, both the circumburst medium density and the GRB classification based on the gamma-ray energy and spectrum suggest that GRB 100418A would be a Type II GRB. These results make a great puzzle on the progenitors of this kind of events, if they belong to the same population.

    • Statistical Properties of Gamma-Ray Burst Host Galaxies

      Jie-Min Chen Jin Zhang Lan-Wei Jia En-Wei Liang

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      A statistical analysis of gamma-ray burst host galaxies is presented and a clear metallicity-stellar mass relation is found in our sample. A trend that a more massive host galaxy tends to have a higher star-formation rate is also found. No correlation is found between 𝐴V and 𝑁H. GRB host galaxies at a higher redshift also tend to have a higher star formation rate, however, even in the same redshift, the star formation rate may vary for three orders of magnitude.

    • Joint Spectral Analysis for Early Bright X-ray Flares of 𝛾-Ray Bursts with Swift BAT and XRT Data

      Fang-Kun Peng You-Dong Hu Xiang-Gao Wang Rui-Jing Lu En-Wei Liang

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      A joint spectral analysis for early bright X-ray flares that were simultaneously observed with Swift BAT and XRT are present. Both BAT and XRT lightcurves of these flares are correlated. Our joint spectral analysis shows that the radiations in the two energy bands are from the same spectral component, which can be well fitted with a single power-law. Except for the flares in GRBs 060904B and 100906A, the photon spectral indices are < 2.0, indicating the peak energies (𝐸p) of the prompt 𝛾-rays should be above the high energy end of the BAT band.

    • Spectral Lag Evolution among 𝛾-Ray Burst Pulses

      Lan-Wei Jia Yun-Feng Liang En-Wei Liang

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      We analyse the spectral lag evolution of 𝛾-ray burst (GRB) pulses with observations by CGRO/BATSE. No universal spectral lag evolution feature and pulse luminosity-lag relation within a GRB is observed.Our results suggest that the spectral lag would be due to radiation physics and dynamics of a given emission episode, possibly due to the longer lasting emission in a lower energy band, and the spectral lag may not be an intrinsic parameter to discriminate the long and short GRBs.

  • Journal of Astrophysics and Astronomy | News

    • Continuous Article Publication

      Posted on January 27, 2016

      Since January 2016, the Journal of Astrophysics and Astronomy has moved to Continuous Article Publishing (CAP) mode. This means that each accepted article is being published immediately online with DOI and article citation ID with starting page number 1. Articles are also visible in Web of Science immediately. All these have helped shorten the publication time and have improved the visibility of the articles.

    • Editorial Note on Continuous Article Publication

      Posted on July 25, 2019

      Click here for Editorial Note on CAP Mode

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