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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"

26316 results found.

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

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