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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"

26509 results found.

  1. GRB990123 Optical Observation
  2. Possible identification of SN1999E with GRB980910
  3. Optical Observations of GRB 981220
  4. GRB 981226: radio variable
  5. GRB981220
  6. GRB981220, Correction to GCN 179
  7. GRB 981220 Optical observations
  8. GRB 981226 Optical Observations
  9. GRB 981220 and GRB 981226, optical observations
  10. GRB981226 Optical Observations
  11. GRB981226 BeppoSAX follow up
  12. GRB 981226
  13. GRB 981226 optical observations
  14. GRB981220 B, R and I band observations
  15. Optical Observations of GRB981226
  16. GRB 981220:Optical Observations
  17. GRB 981226 optical observations
  18. GRB 981220
  19. GRB 981220, radio observations
  20. GRB981220 I-band Observations
  21. GRB 981220
  22. GRB 980326/Host Galaxy
  23. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  24. BeppoSAX NFI Observation of GRB980425
  25. GRB980329 R,I flux calibration and R,I,K upper limits
  26. GRB980425 Optical Follow-up
  27. GRB 980923 BATSE Observations
  28. SGR1900+14, BeppoSAX-GRBM observations
  29. GRB970508 optical observations
  30. GRB971214, association with a Galactic star?
  31. GRB980519, Optical Observations
  32. GRB980703 - BeppoSAX/GRBM detection
  33. GRB980703 optical photometry
  34. GRB 980703: BATSE Observations
  35. GRB980703 optical observations
  36. GRB980703: Radio transient
  37. GRB 980703: Spectrum of the proposed optical counterpart
  38. GRB980703 Transient Optical Follow-Up
  39. GRB980703: LOTIS observation at early times
  40. GRB980613 Optical Observations
  41. GRB980703 (I band observations)
  42. BeppoSAX NFI observations of GRB 980703
  43. GRB980519 observation report
  44. GRB980703 optical followup
  45. Radio observations of SGRs
  46. SGR1900+14 field optical observations
  47. GRB980613, optical observations
  48. GRB 980613: Optical transient and its host galaxy
  49. SGR1627-41, RXTE/ASM observations
  50. GRB 980613: Detection of the probable host galaxy
  51. Reduced error box of SGR 1627-41
  52. GRB 980613: BATSE Observations
  53. GRB 980613 Optical Observations
  54. GRB 980613 optical observations
  55. Discovery of a new SGR source, SGR1627-41
  56. GRB980613 Optical Observations
  57. GRB980613 observations from Palomar
  58. GRB 980613 optical/IR obs.
  59. GRB980613 Near Infra-Red Observations
  60. GRB971214 Secondary Standards
  61. GRB980519 Secondary Standards
  62. BATSE on-board GRB trigger change
  63. GRB 980519 Optical Observations
  64. GRB 980519
  65. GRB980519 optical observations
  66. GRB 980519 Optical Observations
  67. GRB980519 BATSE Observations
  68. GRB980519 Optical Observations
  69. GRB980519 Optical Observations
  70. GRB 980519 Optical Observations
  71. GRB980515, BeppoSAX IAUC to be submitted
  72. BSAX Observations of GRB980425 field
  73. IPN web site of GRBs
  74. GRB980425 BATSE observations
  75. SAX J0840.7+2248 Optical Observations
  76. GRB980425: optical obs.
  77. GRB980425: Radio Observations
  78. report on BSAX observations of GRB980425
  79. GRB 980329 ROSAT observation
  80. GRB980326 X-ray Observations
  81. GRB980326, optical observations
  82. GRB980326, optical observations
  83. GRB980329, Fading IR counterpart to radio source
  84. GRB980329 Keck K-band observations
  85. GRB980329 sub-millimeter observations
  86. GRB980329 optical observations
  87. GRB980329 near-IR observations
  88. GRB980329 near-IR observations
  89. GRB980326 optical observations
  90. GRB980329 optical observations
  91. GRB980329 VLA observations
  92. GRB980329 optical observations
  93. GRB980329 optical observations
  94. GRB980326 optical observations
  95. GRB980326 optical observations
  96. Optical Observations of GRB 970508
  97. Near-IR follow-up on GRB 971227
  98. Optical Observations of the GRB 971227 field
  99. Optical Observations on GRB 971227
  100. GRB971227: Plaskett R-band observations

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