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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32568 results found.

  1. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  2. VLA observations of SGR 1806-20
  3. SGR1806 VLA Observations
  4. VLA observations of SGR 1806-20
  5. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  6. GRB 041217: Optical observations
  7. GRB041219, early time observations
  8. The giant outburst from SGR 1806-20
  9. IPN localization of giant flare from SGR1806-20
  10. GRB041228: ROTSE-III Optical Observations
  11. GRB041219; RXTE ASM Observations
  12. NIR Observations of GRB 041219
  13. GRB041226: ROTSE-III Optical Observations
  14. GRB041223: decay of the afterglow
  15. GRB041224: ROTSE-III Optical Observations
  16. GRB 041224: near-infrared observations with REM
  17. GRB 041223: XRT afterglow spectrum and light curve
  18. GRB 041223 Fluence measured by Swift-BAT
  19. GRB041223: optical and NIR observations with REM
  20. Swift-BAT Time History of GRB041219
  21. GRB 041219: TAROT optical observations
  22. GRB 041223: J-band observations of the afterglow
  23. GRB 041223: Detection of Optical Transient with LCO40
  24. GRB041223: Swift XRT Detection of X-ray Afterglow Emission
  25. GRB 041219c: PROMPT Observations
  26. GRB041223: ROTSE-III Optical Observations
  27. GRB 041218: optical observations
  28. Very high activity of SGR 1806-20
  29. GRB 041219: Second Epoch WSRT Radio Observations
  30. GRB 041219: WSRT Radio Afterglow Detection
  31. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  32. GRB 041218: Optical observations
  33. GRB 041219 : optical follow-up observations
  34. Deep RAPTOR observations during GRB 041219
  35. GRB 041218 Optical Observations
  36. GRB 041219 Optical Observations
  37. GRB041219: Optical Afterglow Detection
  38. GRB041219: Continued NIR Observations
  39. GRB 041219: Radio Afterglow Detection
  40. GRB 041218 : Radio Observations
  41. GRB 041218: R-band optical observations
  42. GRB041218: Liverpool Telescope optical observations
  43. GRB041218: optical observations
  44. GRB041219: Confirmed NIR Afterglow
  45. Swift-BAT detection of the bright long burst GRB041219
  46. GRB 041218: Optical Observation
  47. GRB 041219: Infrared Afterglow Candidate
  48. GRB041219, BVRcIc field calibration
  49. GRB 041219: Infrared Afterglow Candidate
  50. GRB041218, BVRcIc field calibration
  51. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  52. GRB 041217: PROMPT Observations
  53. GRB041218: optical observations
  54. GRB041217: optical limit 30 min after GRB
  55. GRB 041218; optical candidate
  56. GRB 041218: Optical observations
  57. GRB 041217: LCO40 Optical Observations and Possible Candidates
  58. GRB041217: Optical Observations
  59. GRB041217: NIR and optical observations with REM
  60. GRB041217: Infrared Observations
  61. GRB041217: The First GRB Located On-Board Swift
  62. GRB041211: Faulkes Telescope continued optical monitoring
  63. Optical Transient in Lynx not a GRB
  64. Optical transient (GRB?) in Lynx
  65. GRB041211: Continued P60 Observations
  66. GRB041211, Faulkes Telescope optical observation
  67. GRB041211, BVRcIc field calibration
  68. GRB 041211: Infrared Observations
  69. GRB 041211: Optical follow-up in East Asian region
  70. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  71. GRB041015: Near-Infrared observations
  72. GRB 040924: Afterglow Color
  73. GRB 041006: GETS Optical Afterglow Observation
  74. Summary of the recent bursts from SGR 1806-20
  75. GRB 041006: Optical Observations
  76. GRB041006, late-time optical photometry
  77. GRB041006: RTT150 Optical Observations
  78. GRB041015 : Multi epoch optical observations
  79. GRB041006: RTT150 Optical Observations
  80. GRB 041016: Optical limits
  81. GRB 041015: Optical Observations at Rikubetsu
  82. GRB041006: Near Infrared observations
  83. GRB040924, BVRcIc field calibration
  84. GRB 041015: Optical limit at Osaka University
  85. GRB041015 : Optical follow-up at Kiso
  86. GRB 041006 R observations in Loiano
  87. GRB041006: VLT observations of the afterglow and host galaxy
  88. GRB041006: Optical observations and Potential host galaxy
  89. GRB041006, BVRcIc field calibration
  90. GRB 040924: VLT spectroscopy
  91. GRB 041006: SARA afterglow observations
  92. GRB041006, optical observation in CrAO
  93. Search for SN light in XRF 040912 with MEGACAM
  94. GRB 040916: Afterglow Color at Early Times
  95. GRB 041006 Optical afterglow observations
  96. GRB 041006: BR observations with VATT
  97. GRB 041006: Redshift confirmed
  98. GRB041006: Liverpool Telescope optical observations
  99. GRB 041006: Colour measurement
  100. GRB041006: break in the light curve

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