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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"

32485 results found.

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

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