The broadband counterpart of the short GRB 200522A at z = 0.5536: a luminous kilonova or a collimated outflow with a reverse shock?

Research output: Contribution to journalArticlepeer-review

Standard

The broadband counterpart of the short GRB 200522A at z = 0.5536 : a luminous kilonova or a collimated outflow with a reverse shock? / Fong, W.; Laskar, T.; Rastinejad, J.; Escorial, A. Rouco; Schroeder, G.; Barnes, J.; Kilpatrick, C. D.; Paterson, K.; Berger, E.; Metzger, B. D.; Dong, Y.; Nugent, A. E.; Strausbaugh, R.; Blanchard, P. K.; Goyal, A.; Cucchiara, A.; Terreran, G.; Alexander, K. D.; Eftekhari, T.; Fryer, C.; Margalit, B.; Margutti, R.; Nicholl, Matt.

In: The Astrophysical Journal, Vol. 906, No. 2, 127, 15.01.2021.

Research output: Contribution to journalArticlepeer-review

Harvard

Fong, W, Laskar, T, Rastinejad, J, Escorial, AR, Schroeder, G, Barnes, J, Kilpatrick, CD, Paterson, K, Berger, E, Metzger, BD, Dong, Y, Nugent, AE, Strausbaugh, R, Blanchard, PK, Goyal, A, Cucchiara, A, Terreran, G, Alexander, KD, Eftekhari, T, Fryer, C, Margalit, B, Margutti, R & Nicholl, M 2021, 'The broadband counterpart of the short GRB 200522A at z = 0.5536: a luminous kilonova or a collimated outflow with a reverse shock?', The Astrophysical Journal, vol. 906, no. 2, 127. https://doi.org/10.3847/1538-4357/abc74a

APA

Fong, W., Laskar, T., Rastinejad, J., Escorial, A. R., Schroeder, G., Barnes, J., Kilpatrick, C. D., Paterson, K., Berger, E., Metzger, B. D., Dong, Y., Nugent, A. E., Strausbaugh, R., Blanchard, P. K., Goyal, A., Cucchiara, A., Terreran, G., Alexander, K. D., Eftekhari, T., ... Nicholl, M. (2021). The broadband counterpart of the short GRB 200522A at z = 0.5536: a luminous kilonova or a collimated outflow with a reverse shock? The Astrophysical Journal, 906(2), [127]. https://doi.org/10.3847/1538-4357/abc74a

Vancouver

Author

Fong, W. ; Laskar, T. ; Rastinejad, J. ; Escorial, A. Rouco ; Schroeder, G. ; Barnes, J. ; Kilpatrick, C. D. ; Paterson, K. ; Berger, E. ; Metzger, B. D. ; Dong, Y. ; Nugent, A. E. ; Strausbaugh, R. ; Blanchard, P. K. ; Goyal, A. ; Cucchiara, A. ; Terreran, G. ; Alexander, K. D. ; Eftekhari, T. ; Fryer, C. ; Margalit, B. ; Margutti, R. ; Nicholl, Matt. / The broadband counterpart of the short GRB 200522A at z = 0.5536 : a luminous kilonova or a collimated outflow with a reverse shock?. In: The Astrophysical Journal. 2021 ; Vol. 906, No. 2.

Bibtex

@article{ad490ececde24c6993fdd035f3a4f064,
title = "The broadband counterpart of the short GRB 200522A at z = 0.5536: a luminous kilonova or a collimated outflow with a reverse shock?",
abstract = "We present the discovery of the radio afterglow and near-infrared (NIR) counterpart of the Swift short gamma-ray burst (GRB) GRB 200522A, located at a small projected offset of ≈1 kpc from the center of a young, star-forming host galaxy at z = 0.5536. The radio and X-ray luminosities of the afterglow are consistent with those of on-axis cosmological short GRBs. The NIR counterpart, revealed by our Hubble Space Telescope observations at a rest-frame time of ≈2.3 days, has a luminosity of ≈(1.3–1.7) × 1042 erg s−1. This is substantially lower than on-axis short GRB afterglow detections but is a factor of ≈8–17 more luminous than the kilonova of GW170817 and significantly more luminous than any kilonova candidate for which comparable observations exist. The combination of the counterpart's color (i − y = −0.08 ± 0.21; rest frame) and luminosity cannot be explained by standard radioactive heating alone. We present two scenarios to interpret the broadband behavior of GRB 200522A: a synchrotron forward shock with a luminous kilonova (potentially boosted by magnetar energy deposition), or forward and reverse shocks from a ≈14°, relativistic (Γ0 ≳ 10) jet. Models that include a combination of enhanced radioactive heating rates, low-lanthanide mass fractions, or additional sources of heating from late-time central engine activity may provide viable alternate explanations. If a stable magnetar was indeed produced in GRB 200522A, we predict that late-time radio emission will be detectable starting ≈0.3–6 yr after the burst for a deposited energy of ≈1053 erg. Counterparts of similar luminosity to GRB 200522A associated with gravitational wave events will be detectable with current optical searches to ≈250 Mpc.",
author = "W. Fong and T. Laskar and J. Rastinejad and Escorial, {A. Rouco} and G. Schroeder and J. Barnes and Kilpatrick, {C. D.} and K. Paterson and E. Berger and Metzger, {B. D.} and Y. Dong and Nugent, {A. E.} and R. Strausbaugh and Blanchard, {P. K.} and A. Goyal and A. Cucchiara and G. Terreran and Alexander, {K. D.} and T. Eftekhari and C. Fryer and B. Margalit and R. Margutti and Matt Nicholl",
year = "2021",
month = jan,
day = "15",
doi = "10.3847/1538-4357/abc74a",
language = "English",
volume = "906",
journal = "The Astrophysical Journal",
issn = "0004-637X",
publisher = "Institute of Physics Publishing Ltd",
number = "2",

}

RIS

TY - JOUR

T1 - The broadband counterpart of the short GRB 200522A at z = 0.5536

T2 - a luminous kilonova or a collimated outflow with a reverse shock?

AU - Fong, W.

AU - Laskar, T.

AU - Rastinejad, J.

AU - Escorial, A. Rouco

AU - Schroeder, G.

AU - Barnes, J.

AU - Kilpatrick, C. D.

AU - Paterson, K.

AU - Berger, E.

AU - Metzger, B. D.

AU - Dong, Y.

AU - Nugent, A. E.

AU - Strausbaugh, R.

AU - Blanchard, P. K.

AU - Goyal, A.

AU - Cucchiara, A.

AU - Terreran, G.

AU - Alexander, K. D.

AU - Eftekhari, T.

AU - Fryer, C.

AU - Margalit, B.

AU - Margutti, R.

AU - Nicholl, Matt

PY - 2021/1/15

Y1 - 2021/1/15

N2 - We present the discovery of the radio afterglow and near-infrared (NIR) counterpart of the Swift short gamma-ray burst (GRB) GRB 200522A, located at a small projected offset of ≈1 kpc from the center of a young, star-forming host galaxy at z = 0.5536. The radio and X-ray luminosities of the afterglow are consistent with those of on-axis cosmological short GRBs. The NIR counterpart, revealed by our Hubble Space Telescope observations at a rest-frame time of ≈2.3 days, has a luminosity of ≈(1.3–1.7) × 1042 erg s−1. This is substantially lower than on-axis short GRB afterglow detections but is a factor of ≈8–17 more luminous than the kilonova of GW170817 and significantly more luminous than any kilonova candidate for which comparable observations exist. The combination of the counterpart's color (i − y = −0.08 ± 0.21; rest frame) and luminosity cannot be explained by standard radioactive heating alone. We present two scenarios to interpret the broadband behavior of GRB 200522A: a synchrotron forward shock with a luminous kilonova (potentially boosted by magnetar energy deposition), or forward and reverse shocks from a ≈14°, relativistic (Γ0 ≳ 10) jet. Models that include a combination of enhanced radioactive heating rates, low-lanthanide mass fractions, or additional sources of heating from late-time central engine activity may provide viable alternate explanations. If a stable magnetar was indeed produced in GRB 200522A, we predict that late-time radio emission will be detectable starting ≈0.3–6 yr after the burst for a deposited energy of ≈1053 erg. Counterparts of similar luminosity to GRB 200522A associated with gravitational wave events will be detectable with current optical searches to ≈250 Mpc.

AB - We present the discovery of the radio afterglow and near-infrared (NIR) counterpart of the Swift short gamma-ray burst (GRB) GRB 200522A, located at a small projected offset of ≈1 kpc from the center of a young, star-forming host galaxy at z = 0.5536. The radio and X-ray luminosities of the afterglow are consistent with those of on-axis cosmological short GRBs. The NIR counterpart, revealed by our Hubble Space Telescope observations at a rest-frame time of ≈2.3 days, has a luminosity of ≈(1.3–1.7) × 1042 erg s−1. This is substantially lower than on-axis short GRB afterglow detections but is a factor of ≈8–17 more luminous than the kilonova of GW170817 and significantly more luminous than any kilonova candidate for which comparable observations exist. The combination of the counterpart's color (i − y = −0.08 ± 0.21; rest frame) and luminosity cannot be explained by standard radioactive heating alone. We present two scenarios to interpret the broadband behavior of GRB 200522A: a synchrotron forward shock with a luminous kilonova (potentially boosted by magnetar energy deposition), or forward and reverse shocks from a ≈14°, relativistic (Γ0 ≳ 10) jet. Models that include a combination of enhanced radioactive heating rates, low-lanthanide mass fractions, or additional sources of heating from late-time central engine activity may provide viable alternate explanations. If a stable magnetar was indeed produced in GRB 200522A, we predict that late-time radio emission will be detectable starting ≈0.3–6 yr after the burst for a deposited energy of ≈1053 erg. Counterparts of similar luminosity to GRB 200522A associated with gravitational wave events will be detectable with current optical searches to ≈250 Mpc.

U2 - 10.3847/1538-4357/abc74a

DO - 10.3847/1538-4357/abc74a

M3 - Article

VL - 906

JO - The Astrophysical Journal

JF - The Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 127

ER -