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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"

20815 results found.

  1. "GRB 990123: New BV Observations"
  2. GRB990123 IPN annulus
  3. GRB 990123 Spectroscopic Redshifts
  4. GRB 990123: New Optical Observations, Decay Measure
  5. GRB 990123 Optical Follow-Up
  6. GRB 990123: Possible Gravitationally Lensed Burst?
  7. GRB990123, optical observation
  8. GRB 990123 optical observations
  9. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  10. GRB 990123 radio observations
  11. GRB 990123: Optical Decay Slope
  12. GRB 990123 r-band photometry
  13. GRB 990123 Optical Follow-up
  14. GRB990123, early optical counterpart detection
  15. GRB990123 Optical Observation
  16. Possible identification of SN1999E with GRB980910
  17. Optical Observations of GRB 981220
  18. GRB 981226: radio variable
  19. GRB981220, Optical Observations
  20. GRB 981226 Optical Observations
  21. GRB981226 Optical Observations
  22. GRB981226 BeppoSAX follow up
  23. GRB 981226
  24. GRB 981226 optical observations
  25. GRB981220 B, R and I band observations
  26. Optical Observations of GRB981226
  27. GRB 981220:Optical Observations
  28. GRB 981226 - Infrared Observations
  29. GRB 981226 optical observations
  30. GRB 981220, radio observations
  31. GRB 981220
  32. GRB 980326/Host Galaxy
  33. GRB981220 IPN error box
  34. BeppoSAX NFI Observation of GRB980425
  35. GRB980329 R,I flux calibration and R,I,K upper limits
  36. GRB980425 Optical Follow-up
  37. GRB980425: X-ray revised positions
  38. GRB 980923 BATSE Observations
  39. GRB970508 optical observations
  40. GRB971214, association with a Galactic star?
  41. GRB980519, Optical Observations
  42. GRB980703 - BeppoSAX/GRBM detection
  43. GRB 980703 (NFI observations)
  44. GRB980703 optical photometry
  45. GRB980703 optical observations
  46. GRB980703: Radio transient
  47. RXTE Observation of GRB 980706
  48. GRB980703 Transient Optical Follow-Up
  49. GRB980703: LOTIS observation at early times
  50. GRB980613 Optical Observations
  51. GRB 980703
  52. BeppoSAX NFI observations of GRB 980703
  53. GRB980703 optical followup
  54. Radio observations of SGRs
  55. SGR1900+14 field optical observations
  56. GRB 980613 Near-IR observations
  57. GRB 980613: Optical transient and its host galaxy
  58. SGR1627-41, RXTE/ASM observations
  59. GRB 980613: Detection of the probable host galaxy
  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. GRB971214 Secondary Standards
  67. GRB980519 Secondary Standards
  68. BATSE on-board GRB trigger change
  69. GRB 980519 Optical Observations
  70. GRB980519 optical observations
  71. GRB 980519
  72. GRB980519 optical observations
  73. GRB 980519 Optical Observations
  74. GRB980519 Optical Observations
  75. GRB 980519 Optical Observations
  76. GRB980515, BeppoSAX IAUC to be submitted
  77. BATSE on-board GRB trigger change
  78. GRB980519, BeppoSAX-WFC updated position
  79. GRB980515: SAX-WFC updated position
  80. GRB 980425 Radio Light Curve
  81. BSAX Observations of GRB980425 field
  82. IPN web site of GRBs
  83. SAX J0840.7+2248 Optical Observations
  84. GRB980425: optical obs.
  85. GRB980425: Radio Observations
  86. report on BSAX observations of GRB980425
  87. GRB 980329 ROSAT observation
  88. GRB980326 X-ray Observations
  89. GRB980326, optical observations
  90. GRB980326, optical observations
  91. GRB980329
  92. GRB980329 Keck K-band observations
  93. GRB980326 optical observations
  94. GRB980329 optical observations
  95. GRB980329 VLA observations
  96. GRB980329 optical observations
  97. GRB980326 optical observations
  98. GRB980326 optical observations
  99. GRB980326 optical observations
  100. Optical Observations of GRB 970508

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