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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"

32408 results found.

  1. GRB980703 Transient Optical Follow-Up
  2. GRB980703: LOTIS observation at early times
  3. GRB980613 Optical Observations
  4. GRB 980703
  5. GRB 980703 H-band Observations
  6. GRB980703 (optical R observations)
  7. GRB980706
  8. GRB980703: radio source/optical transient
  9. BeppoSAX NFI observations of GRB 980703
  10. GRB 980703: ASM Position & Intensity
  11. GRB980703
  12. GRB980703 optical followup
  13. GRB 980613 Near-IR observations
  14. GRB980613, optical observations
  15. GRB 980613: Optical transient and its host galaxy
  16. GRB 980613: Detection of the probable host galaxy
  17. GRB 980613: BATSE Observations
  18. GRB 980613 Optical Observations
  19. GRB 980613 optical observations
  20. GRB980613 Optical Observations
  21. GRB980613 observations from Palomar
  22. GRB980613 BeppoSAX-NFI follow up
  23. GRB 980613 new optical/IR observations
  24. GRB 980613 optical/IR obs.
  25. GRB980613 Near Infra-Red Observations
  26. GRB980611
  27. GRB980613, BeppoSAX WFC positions
  28. GRB971214 Secondary Standards
  29. GRB980519 Secondary Standards
  30. BATSE on-board GRB trigger change
  31. GRB 980519 Optical Observations
  32. GRB980519 optical observations
  33. GRB 980519
  34. GRB980519 optical observations
  35. GRB 980519 Optical Observations
  36. GRB980519 BATSE Observations
  37. GRB970519, optical follow-up at Schmidt Calern
  38. GRB980519 optical observations
  39. GRB980519 Optical Observations
  40. GRB980519 Optical Observations
  41. GRB980519 IPN POSITION
  42. GRB980519 Optical Observations
  43. GRB 980519 Optical Observations
  44. GRB980519 optical observations
  45. GRB980515, BeppoSAX IAUC to be submitted
  46. BATSE on-board GRB trigger change
  47. BeppoSAX GRB ALERT: updated position of grb980515
  48. GRB 980425 Radio Light Curve
  49. GRB 980425 Brightness Temperature
  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. GRB 980425 optical observations
  57. GRB 980329 ROSAT observation
  58. GRB980326 X-ray Observations
  59. GRB980326, optical observations
  60. GRB980326, optical observations
  61. GRB980329, Fading IR counterpart to radio source
  62. GRByymmdd, Announcement of automation
  63. GRB980326 IPN annulus
  64. GRB980329 sub-millimeter observations
  65. GRB980329 IPN annulus
  66. GRB980329 near-IR observations
  67. GRB980326 optical observations
  68. GRB980329 optical observations
  69. GRB980329 VLA observations
  70. GRB980329 near IR observations
  71. GRB980329 optical observations
  72. GRB980329 optical observations
  73. GRB980326 optical observations
  74. GRB980326 optical observations
  75. GRB970508 SAO RAS optical observations
  76. Optical Observations of GRB 970508
  77. GRB 971214: Redshift from Keck Observations
  78. Near-IR follow-up on GRB 971227
  79. GRB971214: Keck R & I-band Observations
  80. GRB 971227: Optical Observations
  81. Optical Observations of the GRB 971227 field
  82. Optical Observations on GRB 971227
  83. GRB971227: Plaskett R-band observations
  84. GRB 971227: Optical clarifications
  85. Optical Observations for GRB 971227
  86. GRB971227: Further CAHA R-band images
  87. GRB971227: LOTIS observations
  88. GRB 971227: CAHA R-band images
  89. GRB 971227: Optical observations
  90. Sub-millimeter Observations of GRB 971214 at the JCMT
  91. GRB 971214: EUVE Observations
  92. GRB 971214: Redshift from Keck Optical Observations
  93. GRB 971214: Redshift from Keck Optical Observations
  94. GRB 971214: Apache Point Observatory Optical Observations
  95. GRB 971214: KPNO Optical Observations
  96. Optical Observations of GRB 971214 at Keck
  97. GRB 971214: Optical Observations
  98. Radio Observations of GRB 971214 at the VLA
  99. GRB 971214: USNOFS Observations Summary
  100. GRB 971024: KPNO Optical Observations Summary

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