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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"

25222 results found.

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

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