Redshift Degeneracy in the Eiso–Epeak Relation of Gamma-Ray Bursts
نویسنده
چکیده
In this Letter we show that there is a redshift degeneracy in the Eiso–Epeak relation of gamma-ray bursts (GRBs). If a GRB has a redshift solved from the Eiso–Epeak relation that lies in the range of 0.9 < z < 20, a GRB that has the same observed fluence and peak spectral energy but is at a different redshift in that range also satisfies the Eiso– Epeak relation within 1-σ error, implying an extremely large error in the calculated redshift. Even if the data scatter in the Eiso–Epeak relation is reduced by a factor of 2, the error in the predicted redshift is still large enough to prevent from constraining the redshift meaningfully. Hence, the Eiso–Epeak relation is not useful for determining the GRB distance.
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Epeak Relation of Gamma-Ray Bursts
In this Letter we show that there is a redshift degeneracy in the Eiso −Epeak relation of gamma-ray bursts (GRBs). If a GRB has a redshift solved from the Eiso − Epeak relation that lies in the range of 0.9 < z < 20, a GRB that has the same observed fluence and peak spectral energy but is at a different redshift in that range also satisfies the Eiso − Epeak relation within 1-σ error, implying a...
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