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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"

25981 results found.

  1. GRB970508 optical observations
  2. GRB971214, association with a Galactic star?
  3. GRB980519, Optical Observations
  4. GRB980703 - BeppoSAX/GRBM detection
  5. GRB980703 optical photometry
  6. GRB 980703: BATSE Observations
  7. GRB980703 optical observations
  8. GRB980703: Radio transient
  9. GRB 980703: Spectrum of the proposed optical counterpart
  10. GRB980703 Transient Optical Follow-Up
  11. GRB980703: LOTIS observation at early times
  12. GRB980613 Optical Observations
  13. GRB980703 (I band observations)
  14. BeppoSAX NFI observations of GRB 980703
  15. GRB980519 observation report
  16. GRB980703 optical followup
  17. Radio observations of SGRs
  18. SGR1900+14 field optical observations
  19. GRB980613, optical observations
  20. GRB 980613: Optical transient and its host galaxy
  21. SGR1627-41, RXTE/ASM observations
  22. GRB 980613: Detection of the probable host galaxy
  23. Reduced error box of SGR 1627-41
  24. GRB 980613: BATSE Observations
  25. GRB 980613 Optical Observations
  26. GRB 980613 optical observations
  27. Discovery of a new SGR source, SGR1627-41
  28. GRB980613 Optical Observations
  29. GRB980613 observations from Palomar
  30. GRB 980613 optical/IR obs.
  31. GRB980613 Near Infra-Red Observations
  32. GRB971214 Secondary Standards
  33. GRB980519 Secondary Standards
  34. BATSE on-board GRB trigger change
  35. GRB 980519 Optical Observations
  36. GRB 980519
  37. GRB980519 optical observations
  38. GRB 980519 Optical Observations
  39. GRB980519 BATSE Observations
  40. GRB980519 Optical Observations
  41. GRB980519 Optical Observations
  42. GRB 980519 Optical Observations
  43. GRB980515, BeppoSAX IAUC to be submitted
  44. BSAX Observations of GRB980425 field
  45. IPN web site of GRBs
  46. GRB980425 BATSE observations
  47. SAX J0840.7+2248 Optical Observations
  48. GRB980425: optical obs.
  49. GRB980425: Radio Observations
  50. report on BSAX observations of GRB980425
  51. GRB 980329 ROSAT observation
  52. GRB980326 X-ray Observations
  53. GRB980326, optical observations
  54. GRB980326, optical observations
  55. GRB980329, Fading IR counterpart to radio source
  56. GRB980329 Keck K-band observations
  57. GRB980329 sub-millimeter observations
  58. GRB980329 optical observations
  59. GRB980329 near-IR observations
  60. GRB980329 near-IR observations
  61. GRB980326 optical observations
  62. GRB980329 optical observations
  63. GRB980329 VLA observations
  64. GRB980329 optical observations
  65. GRB980329 optical observations
  66. GRB980326 optical observations
  67. GRB980326 optical observations
  68. Optical Observations of GRB 970508
  69. Near-IR follow-up on GRB 971227
  70. Optical Observations of the GRB 971227 field
  71. Optical Observations on GRB 971227
  72. GRB971227: Plaskett R-band observations
  73. GRB 971227: Optical clarifications
  74. GRB971227: Further CAHA R-band images
  75. GRB971227: LOTIS observations
  76. GRB971214: Optical Observations and Calibrations
  77. GRB 971214: Optical Observations
  78. Radio Observations of GRB 971214 at the VLA
  79. GRB 971024: Refined analysis by USNOFS Observations
  80. GRB 971024: KPNO Optical Observations
  81. GRB 970828: Palomar Observations

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