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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

25827 results found.

  1. GRB 021004: V-band Polarimetric Observations
  2. GRB021004: Update Bisei photometric data
  3. IRAM Millimeter detection of GRB 021004
  4. GRB 021004 radio observation
  5. GRB 021004: Optical Photometry at 1.5 Days
  6. GRB021004, BVRcIc field photometry
  7. GRB021004: Optical Spectroscopy
  8. GRB 021004 radio search
  9. XRF020903, BVRI field photometry
  10. XRF020903: TNG and Asiago photometry
  11. GRB 020903: Optical observations at RIKEN
  12. XRF 020903: Correction to GCN 1560
  13. XRF 020903: VRI observations
  14. XRF 020903: R band observations
  15. XRF 020903: Archival Optical Images
  16. Radio Observations of XRF 020903: The Missing Link
  17. XRF 020903: Supernova
  18. IPN triangulation of GRB020923 (two error boxes)
  19. IPN triangulation of GRB020914B
  20. IPN triangulation of GRB020911 (2 large error boxes)
  21. GRB 020305: HST/STIS observations
  22. Confirmation of IPN error box for GRB020910
  23. IPN triangulation of GRB020910
  24. IPN GCN Circulars now to be issued without restriction
  25. Single IPN error box for GRB020904
  26. XRF 020903: optical observation at Kyoto
  27. GRB020322 : HST/STIS observations
  28. XRF 020903: Optical observations
  29. IPN triangulation of GRB020904
  30. INTEGRAL GRBs added to GCN
  31. SGR1900+14 burst localized by HETE
  32. GRB020813: High-resolution optical spectroscopy
  33. GRB020812: negative optical observations
  34. GRB 020812: optical observation at Kyoto University
  35. Second epoch K band imaging of GRB 020819
  36. GRB 020813 : HST observations
  37. GRB 020812: early time optical observation at Ouda Station
  38. GRB020813: Magellan BVRI Photometry
  39. GRB 020819: Optical observations
  40. K band observation of GRB 020819
  41. GRB020813: optical and NIR observations
  42. GRB020813: Fading X-ray Afterglow Observed with Chandra
  43. GRB020813, UBVRI field calibration
  44. GRB020812: NIR observations
  45. Polarimetry of GRB020813: evidence for variability
  46. GRB020813 IRAM millimeter observations
  47. GRB020812: optical observations
  48. GRB020813: High-Resolution Optical Observations
  49. GRB 020812: optical observation at Bisei
  50. GRB020813: Early Time Magnitude
  51. Millimeter observation of GRB 020813
  52. GRB020812: optical observations
  53. GRB 020813 : KISO multiband optical observations
  54. GRB020813, optical observations
  55. IPN error box for GRB020813
  56. GRB020813, astrometric position
  57. Spectropolarimetry of GRB 020813
  58. GRB 020812 optical observation
  59. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  60. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  61. HST Imaging of the Host of GRB 011121
  62. GRB020801, optical afterglow candidate
  63. GRB020331: Late-time Optical Light Curve (re-submission)
  64. GRB020331: Late-time Optical Light Curve
  65. IPN triangulation of GRB020714
  66. IPN triangulation of GRB020715 (=GRB150702)
  67. IPN triangulation of GRB020714
  68. IPN triangulation of GRB150702
  69. GRB 020410: Discovery of Probable OT by HST
  70. GRB 020124, HST observations of the fading afterglow
  71. IPN triangulation of GRB020708
  72. IPN triangulation of GRB020708
  73. Correction to IPN error box for GRB020706
  74. IPN triangulation of GRB020706
  75. GRB 020705: Optical observations
  76. GRB 020625, optical observations
  77. GRB 020625: Optical observations
  78. GRB 020531: optical photometry of Chandra sources
  79. GRB020625 (=H2081): A Long Burst Localized by HETE
  80. The Probable Host Galaxy of GRB/XRF 020427
  81. GRB/XRF 020427, detection of an underlying system with the VLT
  82. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  83. AXP 1E2259+586 optical observations
  84. Fading Optical Source in the Field of GRB020531
  85. GRB 020531, INT+WFC deep optical upper limits
  86. SGR-like Bursts from the AXP 1E 2259+586
  87. GRB020405: polarimetric observations
  88. GRB 020531, simultaneous optical observations
  89. GRB 020531/Candidate Redshift
  90. GRB020531: Detection of Candidate Host Galaxy
  91. GRB020531: Second epoch Chandra observations
  92. GRB020604, optical observations
  93. GRB020604, BVRcIc field photometry
  94. GRB020603, BVRcIc field observations
  95. GRB020531, BVRcIc field photometry
  96. GRB020531 Optical Observations
  97. GRB020531: Observations with the Chandra X-ray Observatory
  98. GRB020531, optical observations
  99. GRB020531: optical observations
  100. GRB020531(=H2042): Optical Observations

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