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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"

25714 results found.

  1. GRB990123, Optical observation
  2. GRB 990123: Optical Decay Slope
  3. GRB 990123 r-band photometry
  4. GRB 990123 Optical Follow-up
  5. GRB990123, early optical counterpart detection
  6. GRB990123 Optical Observation
  7. Possible identification of SN1999E with GRB980910
  8. Optical Observations of GRB 981220
  9. GRB 981226: radio variable
  10. GRB981220
  11. GRB981220, Correction to GCN 179
  12. GRB 981220 Optical observations
  13. GRB 981226 Optical Observations
  14. GRB 981220 and GRB 981226, optical observations
  15. GRB981226 Optical Observations
  16. GRB981226 BeppoSAX follow up
  17. GRB 981226
  18. GRB 981226 optical observations
  19. GRB981220 B, R and I band observations
  20. Optical Observations of GRB981226
  21. GRB 981220:Optical Observations
  22. GRB 981226 optical observations
  23. GRB 981220
  24. GRB 981220, radio observations
  25. GRB981220 I-band Observations
  26. GRB 981220
  27. GRB 980326/Host Galaxy
  28. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  29. BeppoSAX NFI Observation of GRB980425
  30. GRB980329 R,I flux calibration and R,I,K upper limits
  31. GRB980425 Optical Follow-up
  32. GRB 980923 BATSE Observations
  33. SGR1900+14, BeppoSAX-GRBM observations
  34. GRB970508 optical observations
  35. GRB971214, association with a Galactic star?
  36. GRB980519, Optical Observations
  37. GRB980703 - BeppoSAX/GRBM detection
  38. GRB980703 optical photometry
  39. GRB 980703: BATSE Observations
  40. GRB980703 optical observations
  41. GRB980703: Radio transient
  42. GRB 980703: Spectrum of the proposed optical counterpart
  43. GRB980703 Transient Optical Follow-Up
  44. GRB980703: LOTIS observation at early times
  45. GRB980613 Optical Observations
  46. GRB980703 (I band observations)
  47. BeppoSAX NFI observations of GRB 980703
  48. GRB980519 observation report
  49. GRB980703 optical followup
  50. Radio observations of SGRs
  51. SGR1900+14 field optical observations
  52. GRB980613, optical observations
  53. GRB 980613: Optical transient and its host galaxy
  54. SGR1627-41, RXTE/ASM observations
  55. GRB 980613: Detection of the probable host galaxy
  56. Reduced error box of SGR 1627-41
  57. GRB 980613: BATSE Observations
  58. GRB 980613 Optical Observations
  59. GRB 980613 optical observations
  60. Discovery of a new SGR source, SGR1627-41
  61. GRB980613 Optical Observations
  62. GRB980613 observations from Palomar
  63. GRB 980613 optical/IR obs.
  64. GRB980613 Near Infra-Red Observations
  65. GRB971214 Secondary Standards
  66. GRB980519 Secondary Standards
  67. BATSE on-board GRB trigger change
  68. GRB 980519 Optical Observations
  69. GRB 980519
  70. GRB980519 optical observations
  71. GRB 980519 Optical Observations
  72. GRB980519 BATSE Observations
  73. GRB980519 Optical Observations
  74. GRB980519 Optical Observations
  75. GRB 980519 Optical Observations
  76. GRB980515, BeppoSAX IAUC to be submitted
  77. BSAX Observations of GRB980425 field
  78. IPN web site of GRBs
  79. GRB980425 BATSE observations
  80. SAX J0840.7+2248 Optical Observations
  81. GRB980425: optical obs.
  82. GRB980425: Radio Observations
  83. report on BSAX observations of GRB980425
  84. GRB 980329 ROSAT observation
  85. GRB980326 X-ray Observations
  86. GRB980326, optical observations
  87. GRB980326, optical observations
  88. GRB980329, Fading IR counterpart to radio source
  89. GRB980329 Keck K-band observations
  90. GRB980329 sub-millimeter observations
  91. GRB980329 optical observations
  92. GRB980329 near-IR observations
  93. GRB980329 near-IR observations
  94. GRB980326 optical observations
  95. GRB980329 optical observations
  96. GRB980329 VLA observations
  97. GRB980329 optical observations
  98. GRB980329 optical observations
  99. GRB980326 optical observations
  100. GRB980326 optical observations

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