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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"

41688 results found.

  1. GRB010213, Radio Observations
  2. J-Band Observation of GRB 010214.
  3. GRB010214, Radio Observations
  4. GRB010214, optical observations
  5. GRB010213, optical observations
  6. GRB010213, Near-IR observations
  7. Possible InfraRed Transient of GRB 010214.
  8. GRB010214 Optical Observation
  9. GRB010213 (HETE) TAROT observations
  10. GRB 010214, optical observations
  11. GRB010213 detected by HETE
  12. BeppoSAX ALERT: GRB010214
  13. IPN Status Report
  14. HETE Status
  15. GRB010126 opt. obs.
  16. IPN/RXTE TRIANGULATION OF GRB010126
  17. GRB010126: CONCAM crude optical limits during GRB
  18. GRB010126, TNG R-band observations
  19. GRB010126 Optical Observations
  20. GRB010126 optical observations
  21. GRB010126: Optical observations
  22. IPN TRIANGULATION OF GRB010126
  23. IPN/RXTE TRIANGULATION OF GRB010126
  24. GRB 010119, optical observations
  25. GRB010119: Optical observations
  26. Optical Observations of GRB 001018 at Keck
  27. GRB010119, Radio observations
  28. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  29. Optical observations of GRB 001018 with JCAM
  30. IPN TRIANGULATION OF GRB010115
  31. IPN TRIANGULATION OF GRB010109
  32. IPN TRIANGULATION OF GRB010109
  33. GRB010103, optical observations
  34. IPN triangulation of GRB010104
  35. IPN triangulation of GRB010103
  36. GRB 001204: Ks observations
  37. H band observation of GRB 001212
  38. IPN triangulation of GRB001219
  39. GRB 001212 Optical Observation
  40. GRB 001212 Optical Observation
  41. GRB 001212 optical observation
  42. GRB 001212 possible OA in 2MASS
  43. GRB 001212 possible OA
  44. IPN triangulation of GRB001212
  45. GRB001204: Optical observations
  46. Confirmation of IPN position for GRB001204
  47. GRB001204, Radio observations
  48. IPN triangulation of GRB001204 (short/hard)
  49. GRB 001105, further optical observations
  50. GRB001120: Gunn-i observations
  51. GRB001120: Optical observations
  52. GRB001109, optical observations
  53. GRB001120, optical observations
  54. WSRT 4.8 GHz observations of GRB001109
  55. IPN triangulation of GRB001120
  56. Optical/NIR observations of GRB001109
  57. GRB 001109: deep JHK upper limits
  58. GRB 001109 X-ray afterglow with BeppoSAX
  59. CORRECTION to XMM-Newton observation of GRB001025
  60. GRB001109: Optical observations
  61. GRB001109: BeppoSAX/NFI Observations
  62. GRB001109, R-band optical observations
  63. GRB001109, Radio observations
  64. BeppoSAX ALERT: GRB001109
  65. GRB001105, BVRI field photometry
  66. GRB 001105, R-band observation
  67. IPN TRIANGULATION OF GRB001105
  68. GRB 001025B, Optical obervations
  69. GRB 991208: HST Imaging of the Host Galaxy
  70. GRB 001025B, I-band observations
  71. XMM-Newton observation of GRB001025
  72. GRB001025B, Radio observations
  73. GRB 001025 Optical Observations
  74. GRB 001025A, optical observation
  75. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  76. IPN triangulation of GRB001025
  77. GRB001007: Optical observations
  78. ASM Localization of GRB 001025
  79. GRB001007, Radio observations
  80. IPN TRIANGULATION OF GRB001020
  81. GRB001019, Optical Observations
  82. GRB 001018, Possible Radio Afterglow
  83. GRB001018, Gamma Ray Observations
  84. IPN TRIANGULATION OF GRB001019
  85. CORRECTION TO PEAK FLUX OF GRB001018
  86. IPN TRIANGULATION OF GRB001018
  87. IPN TRIANGULATION OF GRB 001017
  88. GRB 000926: Improved Absorber Redshift
  89. V,R,I band observations of GRB000926
  90. The Likely Optical/Infrared Afterglow of GRB 001011
  91. HETE positions added to GCN
  92. BeppoSAX ALERT: GRB001011
  93. GRB 001007, BVR-band observations
  94. GRB000926 - Amateur Optical Observations
  95. GRB001007: Optical observations
  96. CONCAM null result on GRB001005
  97. IPN triangulation of GRB001007
  98. GRB 000926 : the host galaxy
  99. HETE-2 Launches Successfully
  100. IPN triangulation of GRB001005

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