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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"

32487 results found.

  1. GRB980703 H-band Observations
  2. GRB 980703: Spectrum of the proposed optical counterpart
  3. RXTE Observation of GRB 980706
  4. GRB980703: Spectrum of the proposed optical counterpart
  5. GRB980703 Transient Optical Follow-Up
  6. GRB980703: LOTIS observation at early times
  7. GRB980613 Optical Observations
  8. GRB 980703
  9. GRB980703 (I band observations)
  10. GRB 980703 H-band Observations
  11. GRB980703: radio source/optical transient
  12. BeppoSAX NFI observations of GRB 980703
  13. GRB980519 observation report
  14. Radio observations of SGRs
  15. GRB 980613 Near-IR observations
  16. GRB980613, optical observations
  17. GRB 980613: Optical transient and its host galaxy
  18. SGR1627-41, RXTE/ASM observations
  19. SGR1627-41, Refined IPN annulus location
  20. GRB 980613: Detection of the probable host galaxy
  21. Reduced error box of SGR 1627-41
  22. SGR1627-41, BeppoSAX-GRBM detections
  23. GRB 980613 Optical Observations
  24. GRB 980613 optical observations
  25. GRB980613 Optical Observations
  26. GRB980613 observations from Palomar
  27. GRB 980613 new optical/IR observations
  28. GRB971214 Secondary Standards
  29. GRB980519 Secondary Standards
  30. SGR1900+14
  31. GRB 980519 Optical Observations
  32. GRB980519 optical observations
  33. GRB980519 I-band observations
  34. GRB 980519
  35. GRB980519 optical observations
  36. GRB 980519 Optical Observations
  37. GRB980519 BATSE Observations
  38. GRB970519, optical follow-up at Schmidt Calern
  39. GRB980519 optical observations
  40. GRB980519 Optical Observations
  41. GRB980519 Optical Observations
  42. GRB980519 IPN POSITION
  43. GRB980519 Optical Observations
  44. GRB 980519 Optical Observations
  45. GRB980519 optical observations
  46. GRB980515, BeppoSAX IAUC to be submitted
  47. GRB980519, BeppoSAX-WFC updated position
  48. GRB 980425 Radio Light Curve
  49. GRB 980425 Brightness Temperature
  50. BSAX Observations of GRB980425 field
  51. IPN web site of GRBs
  52. GRB980425 BATSE observations
  53. SAX J0840.7+2248 Optical Observations
  54. GRB 980425 optical observations
  55. GRB980425: optical obs.
  56. GRB980425: Radio Observations
  57. GRB 980425 optical observations
  58. GRB980326, optical observations
  59. GRB980326, optical observations
  60. GRB980329, Fading IR counterpart to radio source
  61. GRByymmdd, Announcement of automation
  62. GRB980326 IPN annulus
  63. GRB980329
  64. GRB980329 Keck K-band observations
  65. GRB980329 sub-millimeter observations
  66. GRB980329 IPN annulus
  67. GRB980329 optical observations
  68. GRB980329 near-IR observations
  69. GRB980329 optical observations
  70. GRB980326 optical observations
  71. GRB980326 optical observations
  72. GRB970508 SAO RAS optical observations
  73. GRB 971214: Redshift from Keck Observations
  74. Near-IR follow-up on GRB 971227
  75. GRB971214: Keck R & I-band Observations
  76. GRB 971227: Optical Observations
  77. Optical Observations of the GRB 971227 field
  78. GRB971227: Plaskett R-band observations
  79. GRB 971227: Optical clarifications
  80. GRB971227: LOTIS observations
  81. GRB971214: Optical Observations and Calibrations
  82. Optical Observations of GRB 971214 at Keck
  83. GRB 971024: Refined analysis by USNOFS Observations
  84. GRB 971024: USNO Observations
  85. GRB 970925: BATSE Localization
  86. IRAS 18119-1342 and the possible new SGR
  87. GRB 970228: Keck/LRIS Optical Observations

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