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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"

24592 results found.

  1. GRB 981220
  2. GRB 981220, radio observations
  3. GRB981220 I-band Observations
  4. GRB 981220
  5. GRB 980326/Host Galaxy
  6. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  7. BeppoSAX NFI Observation of GRB980425
  8. GRB980329 R,I flux calibration and R,I,K upper limits
  9. GRB980425 Optical Follow-up
  10. GRB 980923 BATSE Observations
  11. SGR1900+14, BeppoSAX-GRBM observations
  12. GRB970508 optical observations
  13. GRB971214, association with a Galactic star?
  14. GRB980519, Optical Observations
  15. GRB980703 - BeppoSAX/GRBM detection
  16. GRB980703 optical photometry
  17. GRB 980703: BATSE Observations
  18. GRB980703 optical observations
  19. GRB980703: Radio transient
  20. GRB 980703: Spectrum of the proposed optical counterpart
  21. GRB980703 Transient Optical Follow-Up
  22. GRB980703: LOTIS observation at early times
  23. GRB980613 Optical Observations
  24. GRB980703 (I band observations)
  25. BeppoSAX NFI observations of GRB 980703
  26. GRB980519 observation report
  27. GRB980703 optical followup
  28. Radio observations of SGRs
  29. SGR1900+14 field optical observations
  30. GRB980613, optical observations
  31. GRB 980613: Optical transient and its host galaxy
  32. SGR1627-41, RXTE/ASM observations
  33. GRB 980613: Detection of the probable host galaxy
  34. Reduced error box of SGR 1627-41
  35. GRB 980613: BATSE Observations
  36. GRB 980613 Optical Observations
  37. GRB 980613 optical observations
  38. Discovery of a new SGR source, SGR1627-41
  39. GRB980613 Optical Observations
  40. GRB980613 observations from Palomar
  41. GRB 980613 optical/IR obs.
  42. GRB980613 Near Infra-Red Observations
  43. GRB971214 Secondary Standards
  44. GRB980519 Secondary Standards
  45. BATSE on-board GRB trigger change
  46. GRB 980519 Optical Observations
  47. GRB 980519
  48. GRB980519 optical observations
  49. GRB 980519 Optical Observations
  50. GRB980519 BATSE Observations
  51. GRB980519 Optical Observations
  52. GRB980519 Optical Observations
  53. GRB 980519 Optical Observations
  54. GRB980515, BeppoSAX IAUC to be submitted
  55. BSAX Observations of GRB980425 field
  56. IPN web site of GRBs
  57. GRB980425 BATSE observations
  58. SAX J0840.7+2248 Optical Observations
  59. GRB980425: optical obs.
  60. GRB980425: Radio Observations
  61. report on BSAX observations of GRB980425
  62. GRB 980329 ROSAT observation
  63. GRB980326 X-ray Observations
  64. GRB980326, optical observations
  65. GRB980326, optical observations
  66. GRB980329, Fading IR counterpart to radio source
  67. GRB980329 Keck K-band observations
  68. GRB980329 sub-millimeter observations
  69. GRB980329 optical observations
  70. GRB980329 near-IR observations
  71. GRB980329 near-IR observations
  72. GRB980326 optical observations
  73. GRB980329 optical observations
  74. GRB980329 VLA observations
  75. GRB980329 optical observations
  76. GRB980329 optical observations
  77. GRB980326 optical observations
  78. GRB980326 optical observations
  79. Optical Observations of GRB 970508
  80. Near-IR follow-up on GRB 971227
  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. GRB971227: Further CAHA R-band images
  86. GRB971227: LOTIS observations
  87. GRB971214: Optical Observations and Calibrations
  88. GRB 971214: Optical Observations
  89. Radio Observations of GRB 971214 at the VLA
  90. GRB 971024: Refined analysis by USNOFS Observations
  91. GRB 971024: KPNO Optical Observations
  92. GRB 970828: Palomar Observations

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