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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"

26519 results found.

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

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