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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"

32596 results found.

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

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