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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"

32795 results found.

  1. GRB 980613: Optical transient and its host galaxy
  2. GRB 980613: Detection of the probable host galaxy
  3. GRB 980613: BATSE Observations
  4. GRB 980613 Optical Observations
  5. GRB 980613 optical observations
  6. GRB980613 Optical Observations
  7. GRB980613 observations from Palomar
  8. GRB980613 BeppoSAX-NFI follow up
  9. GRB 980613 new optical/IR observations
  10. GRB 980613 optical/IR obs.
  11. GRB980613 Near Infra-Red Observations
  12. GRB980611
  13. GRB980613, BeppoSAX WFC positions
  14. GRB971214 Secondary Standards
  15. GRB980519 Secondary Standards
  16. BATSE on-board GRB trigger change
  17. GRB 980519 Optical Observations
  18. GRB980519 optical observations
  19. GRB 980519
  20. GRB980519 optical observations
  21. GRB 980519 Optical Observations
  22. GRB980519 BATSE Observations
  23. GRB970519, optical follow-up at Schmidt Calern
  24. GRB980519 optical observations
  25. GRB980519 Optical Observations
  26. GRB980519 Optical Observations
  27. GRB980519 IPN POSITION
  28. GRB980519 Optical Observations
  29. GRB 980519 Optical Observations
  30. GRB980519 optical observations
  31. GRB980515, BeppoSAX IAUC to be submitted
  32. BATSE on-board GRB trigger change
  33. BeppoSAX GRB ALERT: updated position of grb980515
  34. GRB 980425 Radio Light Curve
  35. GRB 980425 Brightness Temperature
  36. IPN web site of GRBs
  37. GRB980425 BATSE observations
  38. SAX J0840.7+2248 Optical Observations
  39. GRB 980425 optical observations
  40. GRB980425: optical obs.
  41. GRB980425: Radio Observations
  42. GRB 980425 optical observations
  43. GRB 980425 optical observations
  44. GRB 980329 ROSAT observation
  45. GRB980326 X-ray Observations
  46. GRB980326, optical observations
  47. GRB980326, optical observations
  48. GRB980329, Fading IR counterpart to radio source
  49. GRByymmdd, Announcement of automation
  50. GRB980326 IPN annulus
  51. GRB980329 sub-millimeter observations
  52. GRB980329 IPN annulus
  53. GRB980329 near-IR observations
  54. GRB980326 optical observations
  55. GRB980329 optical observations
  56. GRB980329 VLA observations
  57. GRB980329 near IR observations
  58. GRB980329 optical observations
  59. GRB980329 optical observations
  60. GRB980326 optical observations
  61. GRB980326 optical observations
  62. GRB970508 SAO RAS optical observations
  63. Optical Observations of GRB 970508
  64. GRB 971214: Redshift from Keck Observations
  65. Near-IR follow-up on GRB 971227
  66. GRB971214: Keck R & I-band Observations
  67. GRB 971227: Optical Observations
  68. Optical Observations of the GRB 971227 field
  69. Optical Observations on GRB 971227
  70. GRB971227: Plaskett R-band observations
  71. GRB 971227: Optical clarifications
  72. Optical Observations for GRB 971227
  73. GRB971227: Further CAHA R-band images
  74. GRB971227: LOTIS observations
  75. GRB 971227: CAHA R-band images
  76. GRB 971227: Optical observations
  77. Sub-millimeter Observations of GRB 971214 at the JCMT
  78. GRB 971214: EUVE Observations
  79. GRB 971214: Redshift from Keck Optical Observations
  80. GRB 971214: Redshift from Keck Optical Observations
  81. GRB 971214: Apache Point Observatory Optical Observations
  82. GRB 971214: KPNO Optical Observations
  83. Optical Observations of GRB 971214 at Keck
  84. GRB 971214: Optical Observations
  85. Radio Observations of GRB 971214 at the VLA
  86. GRB 971214: USNOFS Observations Summary
  87. GRB 971024: KPNO Optical Observations Summary
  88. GRB 971024: Refined analysis by USNOFS Observations
  89. GRB 971024: KPNO Optical Observations
  90. GRB 971024: USNO Observations
  91. GRB 970925: BATSE Localization
  92. IRAS 18119-1342 and the possible new SGR
  93. Possible new SGR from US Naval Observatory
  94. GRB 970828: Palomar Observations
  95. GRB 970228: Keck/LRIS Optical Observations

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