OUP accepted manuscript

Gupta, Rahul; Oates, S. R.; Castro-Tirado, A. J.; Joshi, Jagdish C.; Hu, Y.-D.; Valeev, A. F.; Zhang, B B; Zhang, Z; Kumar, Amit; Aryan, Amar; Lien, A. Y.; Kumar, Brijesh; Cui, C. Z.; Ch, Wang; Dimple, Dimple; Bhattacharya, Dipankar; Сонбас, Э.; Bai, J. M.; Tello, J. C.; Gorosabel, J.; Cerón, J. M. Castro; Porto, J R F; Misra, Kuntal; Pasquale, M. De; Caballero‐García, M. D.; Jelínek, M.; Kubánek, P.; Minaev, P. Yu.; Cunniffe, R.; Sánchez-Ramírez, R.; Guziy, S.; Jeong, S.; Tiwari, Sugriva Nath; Razzaque, S.; Bhalerao,; Pintado, V C; Соколов, В. В.; Zhao, Xiaohong; Fan, Yufeng; Xin, Yu

doi:10.1093/mnras/stab1573

Cited by 15 publications

(34 citation statements)

References 110 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They also show a moderate correlation with r and p-value of 0.52 and 4.92 × 10 −4 . Therefore, GRB 190530A is consistent with being a "Double tracking" GRB (Both 𝛼 pt and the 𝐸 p follow the "intensity-tracking" trend) similar to GRB 131231A (Li et al 2019) and GRB 140102A (Gupta et al 2021b). The correlation results are shown in Figure A3 in the appendix.…”

Section: Correlation Between Spectral Parametersmentioning

confidence: 55%

“…So far, this tracking behaviour has only been found in a few GRBs, i.e. in GRB 131231A (Li et al 2019) and GRB 140102A (Gupta et al 2021b), the low energy spectral index remains in the synchrotron limit (𝛼 𝑝𝑡 = −2/3). Similarly, in the case of GRB 190530A, 𝛼 pt values are within the synchrotron limits for the first two pulses.…”

Section: Discussionmentioning

confidence: 92%

“…The 𝛼 pt also evolves with time but does not display any typical trends (Crider et al 1997). Recently, Li et al (2019) and Gupta et al (2021b) found that both 𝐸 p and 𝛼 pt track flux ("double-tracking") for GRB 131231A and GRB 140102A.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: Synchrotron Origin?

Gupta,

Chattopadhyay

et al. 2022

Preprint

View full text Add to dashboard Cite

Multi-pulsed GRB 190530A, detected by the GBM and LAT onboard Fermi, is the sixth most fluent GBM burst detected so far. This paper presents the timing, spectral, and polarimetric analysis of the prompt emission observed using AstroSat and Fermi to provide insight into the prompt emission radiation mechanisms. The time-integrated spectrum shows conclusive proof of two breaks due to peak energy and a second lower energy break. Time-integrated (55.43 ± 21.30 %) as well as time-resolved polarization measurements, made by the Cadmium Zinc Telluride Imager (CZTI) onboard AstroSat, show a hint of high degree of polarization. The presence of a hint of high degree of polarization and the values of low energy spectral index (𝛼 pt ) do not run over the synchrotron limit for the first two pulses, supporting the synchrotron origin in an ordered magnetic field. However, during the third pulse, 𝛼 pt exceeds the synchrotron line of death in few bins, and a thermal signature along with the synchrotron component in the time-resolved spectra is observed. Furthermore, we also report the earliest optical observations constraining afterglow polarization using the MASTER (P < 1.3 %) and the redshift measurement (𝑧= 0.9386) obtained with the 10.4m GTC telescopes. The broadband afterglow can be described with a forward shock model for an ISM-like medium with a wide jet opening angle. We determine a circumburst density of 𝑛 0 ∼ 7.41, kinetic energy 𝐸 K ∼ 7.24 ×10 54 erg, and radiated 𝛾-ray energy 𝐸 𝛾,iso ∼ 6.05 ×10 54 erg, respectively.

show abstract

Section: Correlation Between Spectral Parametersmentioning

confidence: 55%

Section: Discussionmentioning

confidence: 92%

See 1 more Smart Citation

Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: Synchrotron Origin?

Gupta,

Chattopadhyay

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…We didn't observe any spectral evolution during this time interval. Using the XRT data and UVOT magnitudes, we created the SED following the methodology described in Chand et al (2020); Gupta et al (2021). We fitted the SED using power-law and broken power-law models using XSPEC (Arnaud, 1996).…”

Section: Photometric Redshiftmentioning

confidence: 99%

GRB 210217A: A short or a long GRB?

Dimple¹,

Misra²,

Ghosh³

et al. 2022

Preprint

View full text Add to dashboard Cite

Gamma-ray bursts are traditionally classified as short and long bursts based on their T 90 value (the time interval during which an instrument observes 5% to 95% of gamma-ray/hard X-ray fluence). However, T 90 is dependent on the detector sensitivity and the energy range in which the instrument operates. As a result, different instruments provide different values of T 90 for a burst. GRB 210217A is detected with different duration by Swift and Fermi. It is classified as a long/soft GRB by Swift-BAT with a T 90 value of 3.76 sec. On the other hand, the sub-threshold detection by Fermi-GBM classified GRB 210217A as a short/hard burst with a duration of 1.024 sec. We present the multi-wavelength analysis of GRB 210217A (lying in the overlapping regime of long and short GRBs) to identify its actual class using multi-wavelength data. We utilized the T 90 -hardness ratio, T 90 -E p , and T 90 -t mvts distributions of the GRBs to find the probability of GRB 210217A being a short GRB. Further, we estimated the photometric redshift of the burst by fitting the joint XRT/UVOT SED and place the burst in the Amati plane. We found that GRB 210217A is an ambiguous burst showing properties of both short and long class of GRBs.

show abstract

“…We utilised the deviance information criterion (DIC; Spiegelhalter et al 2002) to find the best fit model. A more detailed methodology for GBM data analysis is discussed in Gupta et al (2021bGupta et al ( , 2022.…”

Section: Fermi-gbmmentioning

confidence: 99%

The long-active afterglow of GRB 210204A: Detection of the most delayed flares in a Gamma-Ray Burst

Kumar,

Gupta,

Saraogi

et al. 2022

Preprint

View full text Add to dashboard Cite

We present results from extensive broadband follow-up of GRB 210204A over the period of thirty days. We detect optical flares in the afterglow at 7.6 × 10 5 s and 1.1 × 10 6 s after the burst: the most delayed flaring ever detected in a GRB afterglow. At the source redshift of 0.876, the rest-frame delay is 5.8 × 10 5 s (6.71 d). We investigate possible causes for this flaring and conclude that the most likely cause is a refreshed shock in the jet. The prompt emission of the GRB is within the range of typical long bursts: it shows three disjoint emission episodes, which all follow the typical GRB correlations. This suggests that GRB 210204A might not have any special properties that caused late-time flaring, and the lack of such detections for other afterglows might be resulting from the paucity of late-time observations. Systematic late-time follow-up of a larger sample of GRBs can shed more light on such afterglow behaviour. Further analysis of the GRB 210204A shows that the late time bump in the light curve is highly unlikely due to underlying SNe at redshift (z) = 0.876 and is more likely due to the late time flaring activity. The cause of this variability is not clearly quantifiable due to the lack of multi-band data at late time constraints by bad weather conditions. The flare of GRB 210204A is the latest flare detected to date.

show abstract

OUP accepted manuscript

Cited by 15 publications

References 110 publications

Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: Synchrotron Origin?

Probing into emission mechanisms of GRB 190530A using time-resolved spectra and polarization studies: Synchrotron Origin?

GRB 210217A: A short or a long GRB?

The long-active afterglow of GRB 210204A: Detection of the most delayed flares in a Gamma-Ray Burst

Contact Info

Product

Resources

About