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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"

23407 results found.

  1. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  2. GRB 990123 radio observations
  3. GRB 990123: Optical Decay Slope
  4. GRB 990123 r-band photometry
  5. GRB 990123 Optical Follow-up
  6. GRB990123, early optical counterpart detection
  7. GRB990123 Optical Observation
  8. Possible identification of SN1999E with GRB980910
  9. Optical Observations of GRB 981220
  10. GRB 981226: radio variable
  11. GRB981220, Optical Observations
  12. GRB 981226 Optical Observations
  13. GRB981226 Optical Observations
  14. GRB981226 BeppoSAX follow up
  15. GRB 981226
  16. GRB 981226 optical observations
  17. GRB981220 B, R and I band observations
  18. Optical Observations of GRB981226
  19. GRB 981220:Optical Observations
  20. GRB 981226 - Infrared Observations
  21. GRB 981226 optical observations
  22. GRB 981220, radio observations
  23. GRB 981220
  24. GRB 980326/Host Galaxy
  25. GRB981220 IPN error box
  26. BeppoSAX NFI Observation of GRB980425
  27. GRB980329 R,I flux calibration and R,I,K upper limits
  28. GRB980425 Optical Follow-up
  29. GRB980425: X-ray revised positions
  30. GRB 980923 BATSE Observations
  31. GRB970508 optical observations
  32. GRB971214, association with a Galactic star?
  33. GRB980519, Optical Observations
  34. GRB980703 - BeppoSAX/GRBM detection
  35. GRB 980703 (NFI observations)
  36. GRB980703 optical photometry
  37. GRB980703 optical observations
  38. GRB980703: Radio transient
  39. RXTE Observation of GRB 980706
  40. GRB980703 Transient Optical Follow-Up
  41. GRB980703: LOTIS observation at early times
  42. GRB980613 Optical Observations
  43. GRB 980703
  44. BeppoSAX NFI observations of GRB 980703
  45. GRB980703 optical followup
  46. Radio observations of SGRs
  47. SGR1900+14 field optical observations
  48. GRB 980613 Near-IR observations
  49. GRB 980613: Optical transient and its host galaxy
  50. SGR1627-41, RXTE/ASM observations
  51. GRB 980613: Detection of the probable host galaxy
  52. GRB 980613 Optical Observations
  53. GRB 980613 optical observations
  54. Discovery of a new SGR source, SGR1627-41
  55. GRB980613 Optical Observations
  56. GRB980613 observations from Palomar
  57. GRB980613 Near Infra-Red Observations
  58. GRB971214 Secondary Standards
  59. GRB980519 Secondary Standards
  60. BATSE on-board GRB trigger change
  61. GRB 980519 Optical Observations
  62. GRB980519 optical observations
  63. GRB 980519
  64. GRB980519 optical observations
  65. GRB 980519 Optical Observations
  66. GRB980519 Optical Observations
  67. GRB 980519 Optical Observations
  68. GRB980515, BeppoSAX IAUC to be submitted
  69. BATSE on-board GRB trigger change
  70. GRB980519, BeppoSAX-WFC updated position
  71. GRB980515: SAX-WFC updated position
  72. GRB 980425 Radio Light Curve
  73. BSAX Observations of GRB980425 field
  74. IPN web site of GRBs
  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
  84. GRB980329 Keck K-band observations
  85. GRB980326 optical observations
  86. GRB980329 optical observations
  87. GRB980329 VLA observations
  88. GRB980329 optical observations
  89. GRB980326 optical observations
  90. GRB980326 optical observations
  91. GRB980326 optical observations
  92. Optical Observations of GRB 970508
  93. Near-IR follow-up on GRB 971227
  94. Optical Observations of the GRB 971227 field
  95. Optical Observations on GRB 971227
  96. GRB971227: Plaskett R-band observations
  97. GRB 971227: Optical clarifications
  98. GRB971227: Further CAHA R-band images
  99. GRB971227: LOTIS observations
  100. GRB971214: Optical Observations and Calibrations

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