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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"

23403 results found.

  1. GRB010222, optical observations
  2. Redshift of the Optical Transient of GRB010222
  3. GRB010220, Radio and Optical Observations
  4. GRB 010220, simultaneous optical observations
  5. GRB010220: BeppoSAX WFC and GRBM preliminary data
  6. GRB010214, candidate optical afterglow
  7. GRB010214, optical observations
  8. GRB010214: BeppoSAX WFC and GRBM preliminary data
  9. GRB 010214: X-Ray afterglow
  10. GRB 010214 optical observation
  11. J-Band Observation of GRB 010214.
  12. GRB010213, Near-IR observations
  13. Possible InfraRed Transient of GRB 010214.
  14. GRB 010214, optical observations
  15. GRB010213 detected by HETE
  16. GRB010214 refined WFC position
  17. IPN Status Report
  18. HETE Status
  19. IPN/RXTE TRIANGULATION OF GRB010126
  20. GRB010126, TNG R-band observations
  21. IPN TRIANGULATION OF GRB010126
  22. Optical Observations of GRB 001018 at Keck
  23. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  24. Optical observations of GRB 001018 with JCAM
  25. IPN TRIANGULATION OF GRB010115
  26. IPN TRIANGULATION OF GRB010109
  27. IPN TRIANGULATION OF GRB010109
  28. IPN triangulation of GRB010104
  29. IPN triangulation of GRB010103
  30. IPN triangulation of GRB001219
  31. GRB 001212 Optical Observation
  32. GRB 001212 Optical Observation
  33. IPN triangulation of GRB001212
  34. GRB001204: Optical observations
  35. Confirmation of IPN position for GRB001204
  36. IPN triangulation of GRB001204 (short/hard)
  37. GRB 001105, further optical observations
  38. GRB001120, optical observations
  39. WSRT 4.8 GHz observations of GRB001109
  40. IPN triangulation of GRB001120
  41. Optical/NIR observations of GRB001109
  42. GRB 001109: deep JHK upper limits
  43. GRB 001109 X-ray afterglow with BeppoSAX
  44. CORRECTION to XMM-Newton observation of GRB001025
  45. GRB001109, Radio observations
  46. GRB001105 BVRI field photometry correction
  47. GRB001105, BVRI field photometry
  48. IPN TRIANGULATION OF GRB001105
  49. GRB 001025B, Optical obervations
  50. GRB 991208: HST Imaging of the Host Galaxy
  51. GRB 001025B, I-band observations
  52. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  53. IPN triangulation of GRB001025
  54. GRB001007: Optical observations
  55. ASM Localization of GRB 001025
  56. GRB001007, Radio observations
  57. IPN TRIANGULATION OF GRB001020
  58. IPN TRIANGULATION OF GRB001019
  59. IPN TRIANGULATION OF GRB001018
  60. IPN TRIANGULATION OF GRB 001017
  61. V,R,I band observations of GRB000926
  62. HETE positions added to GCN
  63. GRB000926 - Amateur Optical Observations
  64. GRB001007: Optical observations
  65. CONCAM null result on GRB001005
  66. IPN triangulation of GRB001007
  67. IPN triangulation of GRB001005
  68. GRB 000926 Chandra Observation
  69. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  70. GRB000926 - Optical observations
  71. GRB000926 - Optical observations
  72. GRB 000926, Optical Observations
  73. GRB000926 K'-band Observation
  74. J and K band observations of GRB 000926
  75. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  76. CONCAM crude optical limits before and after GRB000926
  77. GRB 000926: Optical candidate
  78. Optical candidate for GRB000926
  79. IPN triangulation of GRB000926
  80. GRB 000911, BVRI field photometry
  81. IPN triangulation of GRB000925
  82. GRB000911, Radio and Optical observations
  83. GRB000911, Radio observations
  84. GRB000911: Optical observations
  85. IPN triangulation of GRB000911
  86. IPN triangulation of GRB000910
  87. GRB 000830: Optical observations
  88. GRB000830: Optical observations
  89. GRB000830, TNG B-band observations
  90. GRB000830, BVRI field photometry
  91. GRB000830: Optical observations
  92. GRB000830: Optical observations
  93. IPN triangulation of GRB000830
  94. IPN localization of GRB000820
  95. GRB000812, TNG R-band observations
  96. IPN localization of GRB000812
  97. IPN localization of GRB000811
  98. GRB000801, VLT-Antu R-band observations
  99. GRB 991208 Host Galaxy Imaging
  100. IPN localization of GRB000801

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