Low redshift calibration of the Amati relation using galaxy clusters

Abstract

In this work, we use the angular diameter distances of 38 galaxy clusters with joint X-ray/SZE observation to circumvent the circularity problem in the Amati relation for Gamma-ray Bursts (GRBs). Assuming the validity of cosmic-distance duality relation, we obtain the luminosity distance from the cluster angular diameter distance and use that to calculate the isotropic equivalent energy of two different GRB datasets, after restricting the GRB redshift range to z < 0.9. We then use these GRB datasets to test the Amati relation at the low redshifts using the galaxy cluster distances. Our best-fit Amati relation parameters are consistent with a previous estimate for the same dataset. The intrinsic scatter which we obtain for the two datasets is about 45% and 15%, and is comparable with that found by other distance anchors used to study the Amati relation.

Gamma rays bursts: a viable cosmological probe?

“…Parameters Galaxy cluster [29] Based on this analysis, the error bars on Amati relation parameter reduces as compared to the results obtained by using the galaxy cluster data [29]. This suggests that the analysis used here is more accurate and precise in constraining the desired parameters (see table 2 and figure 3).…”

“…This approach was also used in literature along with the enlarged Hubble data generated using various machine learning tools and BAO data to investigate the correlation [25,72]. In a recent work, a model independent approach has been used to constrain the Amati relation parameters and the intrinsic scatter [29]. The authors used a non-parametric technique on the Galaxy cluster data to obtain d A corresponding to the GRBs redshift which is further used to determine d L assuming CDDR to be valid.…”

“…• Recently N. Liang et al used GP with Type Ia SNe data till redshift z < 1.4 [24] and G. Govindaraj et al with Galaxy cluster data upto z < 0.9 [29], to calibrate the Amati relation. In the latter, authors have to assume that the Cosmic Distance Duality Relation (CDDR) is valid to get the luminosity distance from the d A obtained from Galaxy cluster data.…”

“…Observational Hubble data points have been used in literature to calibrate the Amati relation and approximate the cosmic evolution through a Bezier parametric curve [18,[25][26][27][28]. In a recent work, the angular diameter distances from galaxy clusters have been used to calibrate the Amati relation at low redshifts [29].…”

Astrophysical and Cosmological Searches for Lorentz Invariance Violation

“…Subsequently, a search for LIV using polarization measurements obtained by ASTROSAT for seven GRBs [200], as well as all of the five previously detected polarized GRBs was carried out [201] by applying a new technique proposed in [202]. For GRBs with unconfirmed redshifts, lower limits on each of the GRB redshifts were obtained by assuming the GRBs fall within 2σ of the Amati relation [203,204]. This work pointed out that all previous LIV-based limits from polarized GRBs, which were obtained by assuming that the rotation angle of the polarization vector (∆ θ ), given by ∆ θ ≤ π/2 could be ameliorated by applying the technique proposed in [202].…”