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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"

15985 results found.

  1. GRB980703 (optical R observations)
  2. GRB980703: radio source/optical transient
  3. GRB980519 observation report
  4. GRB980703 optical followup
  5. SGR1900+14 field optical observations
  6. GRB 980613 Near-IR observations
  7. GRB980613, optical observations
  8. GRB 980613: Optical transient and its host galaxy
  9. GRB 980613: Detection of the probable host galaxy
  10. GRB 980613 Optical Observations
  11. GRB 980613 optical observations
  12. GRB980613 Optical Observations
  13. GRB980613 observations from Palomar
  14. GRB 980613 new optical/IR observations
  15. GRB 980613 optical/IR obs.
  16. GRB980613 Near Infra-Red Observations
  17. GRB971214 Secondary Standards
  18. GRB980519 Secondary Standards
  19. GRB 980519 Optical Observations
  20. GRB980519 optical observations
  21. GRB980519 I-band observations
  22. GRB 980519
  23. GRB980519 optical observations
  24. GRB 980519 Optical Observations
  25. GRB970519, optical follow-up at Schmidt Calern
  26. GRB980519 optical observations
  27. GRB980519 Optical Observations
  28. GRB980519 Optical Observations
  29. GRB980519 IPN POSITION
  30. GRB980519 Optical Observations
  31. GRB 980519 Optical Observations
  32. GRB980519 optical observations
  33. GRB 980425 Brightness Temperature
  34. SAX J0840.7+2248 Optical Observations
  35. GRB 980425 optical observations
  36. GRB980425: optical obs.
  37. GRB980425: Radio Observations
  38. GRB 980425 optical observations
  39. GRB 980425 optical observations
  40. GRB980326 X-ray Observations
  41. GRB980326, optical observations
  42. GRB980326, optical observations
  43. GRB980326 IPN annulus
  44. GRB980329
  45. GRB980329 Keck K-band observations
  46. GRB980329 IPN annulus
  47. GRB980329 optical observations
  48. GRB980329 optical observations
  49. GRB980329 infrared observations
  50. GRB980329 optical observations
  51. GRB980326 optical observations
  52. GRB980329 optical observations
  53. GRB980329 optical observations
  54. GRB980329 optical observations
  55. GRB980329 optical observations
  56. GRB980326 optical observations
  57. GRB980326 optical observations
  58. GRB980326 optical observations
  59. GRB980326 optical observations
  60. GRB970508 SAO RAS optical observations
  61. Optical Observations of GRB 970508
  62. GRB 971214: Redshift from Keck Observations
  63. Near-IR follow-up on GRB 971227
  64. GRB971214: Keck R & I-band Observations
  65. GRB 971227: Optical Observations
  66. Optical Observations of the GRB 971227 field
  67. Optical Observations on GRB 971227
  68. GRB971227: Plaskett R-band observations
  69. GRB 971227: Optical clarifications
  70. Optical Observations for GRB 971227
  71. GRB971227: Further CAHA R-band images
  72. GRB971227: LOTIS observations
  73. GRB 971227: Optical observations
  74. GRB971214: Optical Observations and Calibrations
  75. Sub-millimeter Observations of GRB 971214 at the JCMT
  76. GRB 971214: Redshift from Keck Optical Observations
  77. GRB 971214: Redshift from Keck Optical Observations
  78. GRB 971214: Apache Point Observatory Optical Observations
  79. GRB 971214: KPNO Optical Observations
  80. Optical Observations of GRB 971214 at Keck
  81. GRB 971214: Optical Observations
  82. GRB 971024: KPNO Optical Observations Summary
  83. GRB 971024: KPNO Optical Observations
  84. GRB 970828: Palomar Observations
  85. GRB 970228: Keck/LRIS Optical Observations

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