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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"

27324 results found.

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

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