Variable polarization in the optical afterglow of GRB 021004
arXiv:astro-ph/0305227 · doi:10.1051/0004-6361:20030731
Abstract
We present polarimetric observations of the afterglow of gamma-ray burst (GRB) 021004, obtained with the Nordic Optical Telescope (NOT) and the Very Large Telescope (VLT) between 8 and 17 hours after the burst. Comparison among the observations shows a 45 degree change in the position angle from 9 hours after the burst to 16 hours after the burst, and comparison with published data from later epochs even shows a 90 degree change between 9 and 89 hours after the burst. The degree of linear polarization shows a marginal change, but is also consistent with being constant in time. In the context of currently available models for changes in the polarization of GRBs, a homogeneous jet with an early break time of t_b ~ 1 day provides a good explanation of our data. The break time is a factor 2 to 6 earlier than has been found from the analysis of the optical light curve. The change in the position angle of the polarization rules out a structured jet model for the GRB.
arXiv comment5 pages, 2 figures. Published in A&A letters
References in corpus (27)
- Optical and Long Wavelength Afterglow from Gamma-Ray Bursts
- Jets in GRBs
- Generation of Magnetic Fields in the Relativistic Shock of Gamma-Ray-Burst Sources
- The Dynamics and Light Curves of Beamed Gamma Ray Burst Afterglows
- How to Tell a Jet from a Balloon: A Proposed Test for Beaming in Gamma Ray Bursts
- Shocked by GRB 970228: the afterglow of a cosmological fireball
- Physical parameters of GRB 970508 and GRB 971214 from their afterglow synchrotron emission
- Radio Transients from Gamma-Ray Bursters
- Gamma-Ray Burst Afterglow: Polarization and Analytic Light Curves
- Linear Polarization and Proper Motion in The Afterglow of Beamed GRBs
- The afterglow of GRB 021004: surfing on density waves
- Polarization lightcurves and position angle variation of beamed gamma-ray bursts
- The discovery of polarization in the afterglow of GRB 990510 with the ESO Very Large Telescope
- Variability in GRB Afterglows and GRB 021004
- Optical and near-infrared observations of the GRB020405 afterglow
- Optical Photometry of GRB 021004: The First Month
- Absorption Systems in the Spectrum of GRB 021004
- Strongly Polarized Optical Afterglows of Gamma-Ray Bursts
- The Strongly Polarized Afterglow of GRB 020405
- The unusual optical afterglow of the gamma-ray burst GRB 021004: Color changes and short-time-scale variability
- GRB990712: First Indication of Polarization Variability in a Gamma-ray Burst Afterglow
- The Afterglow of GRB010222: A Case of Continuous Energy Injection
- Broadband Modeling of GRB 021004
- The Spectroscopic Variability of GRB 021004
- Polarization Evolution of the GRB 020405 Afterglow
- Polarimetric observations of GRB 011211
- Is the afterglow of Gamma Ray Burst 021004 unusual?
Cited by in corpus (37)
- Gamma-Ray Bursts: Progress, Problems & Prospects
- Polarization of prompt GRB emission: evidence for electromagnetically-dominated outflow
- Linear Polarization in Gamma-Ray Bursts: The Case for an Ordered Magnetic Field
- The polarisation of afterglow emission reveals GRB jet structure
- A Unified Jet Model of X-Ray Flashes, X-Ray-Rich Gamma-Ray Bursts, and Gamma-Ray Bursts: I. Power-Law-Shaped Universal and Top-Hat-Shaped Variable Opening-Angle Jet Models
- Relativistic Wind Bubbles and Afterglow Signatures
- Rebrightening of XRF 030723: further evidence for a two-component jet in gamma-ray burst
- Evolution of the polarization of the optical afterglow of the gamma-ray burst GRB 030329
- Towards a complete theory of Gamma Ray Bursts
- Probing a GRB progenitor at a redshift of z=2: a comprehensive observing campaign of the afterglow of GRB 030226
- Detailed optical and near-infrared polarimetry, spectroscopy and broadband photometry of the afterglow of GRB 091018: Polarisation evolution
- Polarization in the prompt emission of gamma-ray bursts and their afterglows
- Energy Injection Episodes in Gamma Ray Bursts: The Light Curves and Polarization Properties of GRB 021004
- The complex light-curve of the afterglow of GRB071010A
- Intrinsic and dust-induced polarization in gamma-ray burst afterglows: the case of GRB 021004
- Polarization and light curve variability: the "patchy shell" model
- On the Afterglow and Host Galaxy of GRB021004: A Comprehensive Study with the Hubble Space Telescope
- On the jet structure and magnetic field configuration of GRB 020813
- Gamma-Ray Bursts: Polarization of Afterglows from Two-Component Jets
- Planck-scale constraints on anisotropic Lorentz and CPT invariance violations from optical polarization measurements
- GRB 020813: polarization in the case of a smooth optical decay
- Physics of the GRB 030328 afterglow and its environment
- SCUBA sub-millimeter observations of gamma-ray bursters IV. GRB 021004, 021211, 030115, 030226, 041006
- Optical polarization observations with the MASTER robotic net
- Linear Polarization, Circular Polarization, and Depolarization of Gamma-ray Bursts: A Simple Case of Jitter Radiation
- Polarization of GRB Prompt Emission and its Application to POLAR's Data
- SPLOT: a Snapshot survey for Polarised Light in Optical Transients
- Polarization constraints on the geometry of the magnetic field in the external shock of gamma-ray bursts
- Modeling the Linear Polarization of GRB Afterglows Across the Electromagnetic Spectrum
- Observing the prompt emission of gamma-ray bursts
- On the Polarized Absorption Lines in Gamma-ray Burst Optical Afterglows
- Varying linear polarisation in the dust-free GRB 210610B
- Gamma-ray Burst UV/optical afterglow polarimetry as a probe of Quantum Gravity
- Gamma-Ray Bursts: Jets and Energetics
- Radiation transport equations in non-Riemannian space-times
- Linear and circular polarimetry observations of GRB afterglows
- The most distant optically polarised GRB afterglow: GRB 240419A at z = 5.178