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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"

24927 results found.

  1. GRB 990123 Optical Follow-Up
  2. GRB 990123: Possible Gravitationally Lensed Burst?
  3. GRB990123, optical observation
  4. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  5. GRB 990123, new radio source
  6. GRB990123, Optical observation
  7. GRB 990123 r-band photometry
  8. GRB 990123 Optical Follow-up
  9. GRB990123 Optical Observation
  10. GRB990123, refined SAX-WFC position
  11. Possible identification of SN1999E with GRB980910
  12. Optical Observations of GRB 981220
  13. GRB 981226: radio variable
  14. GRB981220
  15. GRB 981220 Optical observations
  16. GRB 981226 Optical Observations
  17. GRB981226 Optical Observations
  18. GRB981226 BeppoSAX follow up
  19. GRB 981226
  20. GRB 981226 optical observations
  21. Optical Observations of GRB981226
  22. GRB 981220:Optical Observations
  23. GRB 981226 optical observations
  24. GRB 981220
  25. GRB 981220, radio observations
  26. GRB 981220
  27. GRB 981220, optical observations
  28. GRB 980326/Host Galaxy
  29. GRB981220 IPN error box
  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. GRB980703 Very Long Baseline Interferometry
  36. GRB970508 optical observations
  37. GRB980519, Optical Observations
  38. GRB980703 - BeppoSAX/GRBM detection
  39. GRB 980703 (NFI observations)
  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. RXTE Observation of GRB 980706
  46. GRB980703 Transient Optical Follow-Up
  47. GRB980703: LOTIS observation at early times
  48. GRB980613 Optical Observations
  49. GRB 980703
  50. GRB980703 (optical R observations)
  51. BeppoSAX NFI observations of GRB 980703
  52. GRB 980703: ASM Position & Intensity
  53. GRB980703 optical followup
  54. Radio observations of SGRs
  55. SGR1900+14 field optical observations
  56. GRB 980613: Optical transient and its host galaxy
  57. SGR1627-41, RXTE/ASM observations
  58. GRB 980613: Detection of the probable host galaxy
  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. GRB980613 Near Infra-Red Observations
  66. GRB980613, BeppoSAX WFC positions
  67. GRB971214 Secondary Standards
  68. GRB980519 Secondary Standards
  69. SGR1900+14
  70. SGR1900+14
  71. BATSE on-board GRB trigger change
  72. GRB 980519 Optical Observations
  73. GRB 980519
  74. GRB980519 optical observations
  75. GRB 980519 Optical Observations
  76. GRB980519 BATSE Observations
  77. GRB980519 Optical Observations
  78. GRB 980519 Optical Observations
  79. GRB980519 optical observations
  80. GRB980515, BeppoSAX IAUC to be submitted
  81. BATSE on-board GRB trigger change
  82. GRB980519, BeppoSAX-WFC updated position
  83. BeppoSAX GRB ALERT: updated position of grb980515
  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
  96. GRB980329 Keck K-band observations
  97. GRB980329 sub-millimeter observations
  98. GRB980329 IPN annulus
  99. GRB980329 optical observations
  100. GRB980329 near-IR observations

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