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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"

28688 results found.

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

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