Two-component Jets of GRB 160623A as Shocked Jet Cocoon Afterglow

Two components of jets associated with the afterglow of the gamma-ray burst (GRB) 160623A were observed with multifrequency observations including long-term monitoring in a submillimeter range (230 GHz) using the Submillimeter Array. The observed light curves with temporal breaks suggest on the basis of the standard forward-shock synchrotron-radiation model that the X-ray radiation is narrowly collimated with an opening angle , whereas the radio radiation originated from wider jets (∼27°). The temporal and spectral evolutions of the radio afterglow agree with those expected from a synchrotron-radiation modeling with typical physical parameters, except for the fact that the observed wide jet opening angle for the radio emission is significantly larger than the theoretical maximum opening angle. By contrast, the opening angle of the X-ray afterglow is consistent with the typical value of GRB jets. Since the theory of the relativistic cocoon afterglow emission is similar to that of a regular afterglow with an opening angle of ∼30°, the observed radio emission can be interpreted as the shocked jet cocoon emission. This result therefore indicates that the two components of the jets observed in the GRB 160623A afterglow are caused by the jet and the shocked jet cocoon afterglows.

[1]  D. Costantin,et al.  A Decade of Gamma-Ray Bursts Observed by Fermi-LAT: The Second GRB Catalog , 2019, The Astrophysical Journal.

[2]  Y. Urata,et al.  First Detection of Radio Linear Polarization in a Gamma-Ray Burst Afterglow , 2019, The Astrophysical Journal.

[3]  D. A. Kann,et al.  Signatures of a jet cocoon in early spectra of a supernova associated with a γ-ray burst , 2019, Nature.

[4]  S. Golenetskii,et al.  The Konus-Wind Catalog of Gamma-Ray Bursts with Known Redshifts. I. Bursts Detected in the Triggered Mode , 2017, 1710.08746.

[5]  R. Salvaterra,et al.  Behind the dust curtain: the spectacular case of GRB 160623A , 2017, 1708.08835.

[6]  Kevin Heng,et al.  Analytical Models of Exoplanetary Atmospheres. IV. Improved Two-stream Radiative Transfer for the Treatment of Aerosols , 2017, 1708.07915.

[7]  M. Lister,et al.  MOJAVE - XIV. Shapes and opening angles of AGN jets , 2017, 1705.02888.

[8]  T. Piran,et al.  THE OBSERVABLE SIGNATURES OF GRB COCOONS , 2016, 1610.05362.

[9]  N. Omodei,et al.  GRB 160623A / Galactic transient: Fermi-LAT detection. , 2016 .

[10]  O. Roberts,et al.  GRB 160816730A: Fermi GBM detection/observation. , 2016 .

[11]  T. Sakamoto,et al.  GRB 160525C: CALET Gamma-Ray Burst Monitor detection. , 2016 .

[12]  A. Volnova,et al.  GRB 160623A: Mondy optical observations. , 2016 .

[13]  William H. Lee,et al.  GRB 160623A: RATIR Optical and NIR Observations, Afterglow Confirmation. , 2016 .

[14]  T. Sakamoto,et al.  EXTREMELY SOFT X-RAY FLASH AS THE INDICATOR OF OFF-AXIS ORPHAN GRB AFTERGLOW , 2015, 1504.07288.

[15]  Y. Urata,et al.  A New Era of Submillimeter GRB Afterglow Follow-Ups with the Greenland Telescope , 2015, 1503.07594.

[16]  N. Butler,et al.  THE ENERGY DEPENDENCE OF GRB MINIMUM VARIABILITY TIMESCALES , 2015, 1501.05948.

[17]  Y. Urata,et al.  SYNCHROTRON SELF-INVERSE COMPTON RADIATION FROM REVERSE SHOCK ON GRB 120326A , 2014, 1405.4331.

[18]  K. Ioka,et al.  OPENING ANGLES OF COLLAPSAR JETS , 2013, 1304.0163.

[19]  Y. Urata,et al.  ENERGETIC FERMI/LAT GRB 100414A: ENERGETIC AND CORRELATIONS , 2012, 1202.6440.

[20]  A. J. van der Horst,et al.  GAMMA-RAY BURST AFTERGLOW BROADBAND FITTING BASED DIRECTLY ON HYDRODYNAMICS SIMULATIONS , 2011, 1110.5089.

[21]  L. A. Antonelli,et al.  The two-component jet of GRB 080413B , 2010, 1012.0328.

[22]  D. Frail,et al.  AFTERGLOW OBSERVATIONS OF FERMI LARGE AREA TELESCOPE GAMMA-RAY BURSTS AND THE EMERGING CLASS OF HYPER-ENERGETIC EVENTS , 2010, 1004.2900.

[23]  P. N. Bhat,et al.  FERMI OBSERVATIONS OF GRB 090902B: A DISTINCT SPECTRAL COMPONENT IN THE PROMPT AND DELAYED EMISSION , 2009 .

[24]  M. M. Kasliwal,et al.  THE COLLIMATION AND ENERGETICS OF THE BRIGHTEST SWIFT GAMMA-RAY BURSTS , 2009, 0905.0690.

[25]  T. Sakamoto,et al.  JET BREAKS AND ENERGETICS OF Swift GAMMA-RAY BURST X-RAY AFTERGLOWS , 2008, 0812.4780.

[26]  J. P. Osborne,et al.  Methods and results of an automatic analysis of a complete sample of Swift-XRT observations of GRBs , 2008, 0812.3662.

[27]  R. Perna,et al.  Orphan afterglows in the Universal structured jet model for ?-ray bursts , 2007, 0711.4096.

[28]  S. Piranomonte,et al.  Selection effects shaping the gamma ray burst redshift distributions , 2007, 0704.2189.

[29]  J. P. Osborne,et al.  An online repository of Swift/XRT light curves of Γ-ray bursts , 2007, 0704.0128.

[30]  J. Granot,et al.  Two-Component Jet Models of Gamma-Ray Burst Sources , 2004, astro-ph/0410384.

[31]  J. Bloom,et al.  Toward a More Standardized Candle Using Gamma-Ray Burst Energetics and Spectra , 2004, astro-ph/0408413.

[32]  G. Ghirlanda,et al.  The Collimation-corrected Gamma-Ray Burst Energies Correlate with the Peak Energy of Their νFν Spectrum , 2004, astro-ph/0405602.

[33]  Bing Zhang,et al.  Gamma-Ray Bursts: Progress, Problems & Prospects , 2003, astro-ph/0311321.

[34]  D. Frail,et al.  A common origin for cosmic explosions inferred from calorimetry of GRB030329 , 2003, Nature.

[35]  D. Frail,et al.  Gamma-Ray Burst Energetics and the Gamma-Ray Burst Hubble Diagram: Promises and Limitations , 2003, astro-ph/0302210.

[36]  T. Piran,et al.  The Detectability of Orphan Afterglows , 2002, astro-ph/0204203.

[37]  A. Panaitescu,et al.  Properties of Relativistic Jets in Gamma-Ray Burst Afterglows , 2001, astro-ph/0109124.

[38]  S. Djorgovski,et al.  Beaming in Gamma-Ray Bursts: Evidence for a Standard Energy Reservoir , 2001, astro-ph/0102282.

[39]  Re'em Sari,et al.  Lower Limits on Lorentz Factors in Gamma-Ray Bursts , 2000, astro-ph/0011508.

[40]  Tsvi Piran,et al.  Jets in Gamma-Ray Bursts , 1999 .

[41]  T. Piran.  Gamma-ray bursts and the fireball model , 1998, astro-ph/9810256.