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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"

27321 results found.

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

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