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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.

Advanced Search Examples (click to copy):

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

32567 results found.

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

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