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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"

23413 results found.

  1. GRB010214, field photometry
  2. GRB010222, field photometry
  3. GRB010222 further R-band photometry
  4. GRB 010222 Kyoto optical observation
  5. GRB010222 R-BAND OBSERVATION
  6. GRB 010220: Near-IR Observations
  7. GRB010214 follow-up from Hanle
  8. GRB 010222: Near-IR Observations
  9. GRB 010222: Optical Observations
  10. GRB010222, radio observations
  11. GRB010222, optical observations
  12. Redshift of the Optical Transient of GRB010222
  13. GRB010220, Radio and Optical Observations
  14. GRB 010220, simultaneous optical observations
  15. GRB010220: BeppoSAX WFC and GRBM preliminary data
  16. GRB010214, candidate optical afterglow
  17. GRB010214, optical observations
  18. GRB010214: BeppoSAX WFC and GRBM preliminary data
  19. GRB 010214: X-Ray afterglow
  20. GRB 010214 optical observation
  21. J-Band Observation of GRB 010214.
  22. GRB010213, Near-IR observations
  23. Possible InfraRed Transient of GRB 010214.
  24. GRB 010214, optical observations
  25. GRB010213 detected by HETE
  26. GRB010214 refined WFC position
  27. IPN Status Report
  28. HETE Status
  29. IPN/RXTE TRIANGULATION OF GRB010126
  30. GRB010126, TNG R-band observations
  31. IPN TRIANGULATION OF GRB010126
  32. Optical Observations of GRB 001018 at Keck
  33. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  34. Optical observations of GRB 001018 with JCAM
  35. IPN TRIANGULATION OF GRB010115
  36. IPN TRIANGULATION OF GRB010109
  37. IPN TRIANGULATION OF GRB010109
  38. IPN triangulation of GRB010104
  39. IPN triangulation of GRB010103
  40. IPN triangulation of GRB001219
  41. GRB 001212 Optical Observation
  42. GRB 001212 Optical Observation
  43. IPN triangulation of GRB001212
  44. GRB001204: Optical observations
  45. Confirmation of IPN position for GRB001204
  46. IPN triangulation of GRB001204 (short/hard)
  47. GRB 001105, further optical observations
  48. GRB001120, optical observations
  49. WSRT 4.8 GHz observations of GRB001109
  50. IPN triangulation of GRB001120
  51. Optical/NIR observations of GRB001109
  52. GRB 001109: deep JHK upper limits
  53. GRB 001109 X-ray afterglow with BeppoSAX
  54. CORRECTION to XMM-Newton observation of GRB001025
  55. GRB001109, Radio observations
  56. GRB001105 BVRI field photometry correction
  57. GRB001105, BVRI field photometry
  58. IPN TRIANGULATION OF GRB001105
  59. GRB 001025B, Optical obervations
  60. GRB 991208: HST Imaging of the Host Galaxy
  61. GRB 001025B, I-band observations
  62. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  63. IPN triangulation of GRB001025
  64. GRB001007: Optical observations
  65. ASM Localization of GRB 001025
  66. GRB001007, Radio observations
  67. IPN TRIANGULATION OF GRB001020
  68. IPN TRIANGULATION OF GRB001019
  69. IPN TRIANGULATION OF GRB001018
  70. IPN TRIANGULATION OF GRB 001017
  71. V,R,I band observations of GRB000926
  72. HETE positions added to GCN
  73. GRB000926 - Amateur Optical Observations
  74. GRB001007: Optical observations
  75. CONCAM null result on GRB001005
  76. IPN triangulation of GRB001007
  77. IPN triangulation of GRB001005
  78. GRB 000926 Chandra Observation
  79. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  80. GRB000926 - Optical observations
  81. GRB000926 - Optical observations
  82. GRB 000926, Optical Observations
  83. GRB000926 K'-band Observation
  84. J and K band observations of GRB 000926
  85. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  86. CONCAM crude optical limits before and after GRB000926
  87. GRB 000926: Optical candidate
  88. Optical candidate for GRB000926
  89. IPN triangulation of GRB000926
  90. GRB 000911, BVRI field photometry
  91. IPN triangulation of GRB000925
  92. GRB000911, Radio and Optical observations
  93. GRB000911, Radio observations
  94. GRB000911: Optical observations
  95. IPN triangulation of GRB000911
  96. IPN triangulation of GRB000910
  97. GRB 000830: Optical observations
  98. GRB000830: Optical observations
  99. GRB000830, TNG B-band observations
  100. GRB000830, BVRI field photometry

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