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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"

20355 results found.

  1. GRB021004: BVRc photometry
  2. GRB021004 radio observation
  3. GRB 021004: Optical Photometry at 2.5 Days
  4. GRB 021004: polarimetric observations
  5. GRB 021004: V-band Polarimetric Observations
  6. GRB021004: Update Bisei photometric data
  7. GRB 021004 radio observation
  8. GRB 021004: Optical Observations
  9. GRB 021004: Optical Photometry at 1.5 Days
  10. GRB021004, Optical Observations
  11. GRB021004, BVRcIc field photometry
  12. GRB 021004: Optical observations
  13. GRB 021004: optical counterpart
  14. GRB 021004, optical observations
  15. GRB 021004 radio search
  16. GRB 021004: steepening of the optical decay slope
  17. XRF020903, BVRI field photometry
  18. GRB021004: optical observations at Nyrola
  19. GRB021004: optical observations at Bisei
  20. GRB 021004: Kyoto observation
  21. GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time
  22. XRF020903: TNG and Asiago photometry
  23. GRB 020903: Optical observations at RIKEN
  24. XRF 020903: Correction to GCN 1560
  25. XRF 020903: VRI observations
  26. GRB 020903: correction to GCN 1557
  27. XRF 020903: R band observations
  28. XRF 020903: Supernova
  29. IPN triangulation of GRB020923 (two error boxes)
  30. GRB 020305: HST/STIS observations
  31. Confirmation of IPN error box for GRB020910
  32. IPN triangulation of GRB020910
  33. Single IPN error box for GRB020904
  34. XRF 020903: optical observation at Kyoto
  35. GRB020322 : HST/STIS observations
  36. XRF 020903: Optical observations
  37. IPN triangulation of GRB020904
  38. GRB020903(=H2314): An X-Ray Flash Localized by HETE
  39. INTEGRAL GRBs added to GCN
  40. SGR1900+14 burst localized by HETE
  41. GRB020813: High-resolution optical spectroscopy
  42. GRB020812: negative optical observations
  43. GRB 020812: optical observation at Kyoto University
  44. Second epoch K band imaging of GRB 020819
  45. GRB 020813 : HST observations
  46. GRB 020812: early time optical observation at Ouda Station
  47. GRB020813: VRI Decay Slopes
  48. GRB020813: Magellan BVRI Photometry
  49. GRB 020819: Optical observations
  50. IPN triangulation of GRB020819 (HETE 2275)
  51. GRB020813: optical and NIR observations
  52. GRB020813: Fading X-ray Afterglow Observed with Chandra
  53. GRB020813, UBVRI field calibration
  54. Polarimetry of GRB020813: evidence for variability
  55. GRB020812: optical observations
  56. GRB020813: High-Resolution Optical Observations
  57. GRB 020812: optical observation at Bisei
  58. GRB020812: optical observations
  59. GRB 020813 : KISO multiband optical observations
  60. GRB020813, optical observations
  61. IPN error box for GRB020813
  62. GRB020812: possible afterglow candidate
  63. GRB020812: possible afterglow candidate
  64. GRB020813, astrometric position
  65. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time
  66. GRB 020812 optical observation
  67. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  68. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  69. HST Imaging of the Host of GRB 011121
  70. GRB020801, optical afterglow candidate
  71. GRB020331: Late-time Optical Light Curve (re-submission)
  72. GRB020331: Late-time Optical Light Curve
  73. IPN triangulation of GRB020714
  74. IPN triangulation of GRB020715 (=GRB150702)
  75. IPN triangulation of GRB020714
  76. IPN triangulation of GRB150702
  77. GRB 020410: Discovery of Probable OT by HST
  78. IPN triangulation of GRB020708
  79. IPN triangulation of GRB020708
  80. Correction to IPN error box for GRB020706
  81. IPN triangulation of GRB020706
  82. GRB 020705: Optical observations
  83. GRB 020625, optical observations
  84. GRB 020625: Optical observations
  85. GRB 020531: optical photometry of Chandra sources
  86. The Probable Host Galaxy of GRB/XRF 020427
  87. GRB/XRF 020427, detection of an underlying system with the VLT
  88. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  89. SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
  90. AXP 1E2259+586: quasi-simultaneous optical observation
  91. AXP 1E2259+586 optical observations
  92. Fading Optical Source in the Field of GRB020531
  93. GRB 020531, INT+WFC deep optical upper limits
  94. GRB020405: polarimetric observations
  95. GRB 020531, simultaneous optical observations
  96. GRB020531: Second epoch Chandra observations
  97. GRB020604, optical observations
  98. GRB020604, BVRcIc field photometry
  99. GRB020603, BVRcIc field observations
  100. GRB020531, BVRcIc field photometry

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