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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"

18702 results found.

  1. GRB990123 optical observations
  2. GRB 990123 r-band photometry
  3. GRB 990123 Optical Follow-up
  4. GRB990123 Optical Observation
  5. Possible identification of SN1999E with GRB980910
  6. Optical Observations of GRB 981220
  7. GRB 981226: radio variable
  8. GRB 981226 Optical Observations
  9. GRB981226 Optical Observations
  10. GRB981226 BeppoSAX follow up
  11. GRB 981226 radio observations
  12. GRB 981226
  13. GRB 981226 optical observations
  14. radio observations of GRB 981226
  15. GRB981220 B, R and I band observations
  16. GRB 981220:Optical Observations
  17. GRB 981226 optical observations
  18. GRB 981220, radio observations
  19. GRB 981220, radio observations
  20. GRB 981220
  21. GRB 980326/Host Galaxy
  22. GRB981220 IPN error box
  23. BeppoSAX NFI Observation of GRB980425
  24. GRB980329 R,I flux calibration and R,I,K upper limits
  25. GRB980425 Optical Follow-up
  26. GRB 980923 BATSE Observations
  27. GRB980703 Very Long Baseline Interferometry
  28. GRB970508 optical observations
  29. GRB971214, association with a Galactic star?
  30. GRB980519, Optical Observations
  31. GRB980703, Host galaxy multicolor photometry
  32. GRB980703 - BeppoSAX/GRBM detection
  33. GRB 980703 (NFI observations)
  34. GRB980703 optical photometry
  35. GRB980703 optical observations
  36. GRB980703 Transient Optical Follow-Up
  37. GRB980703: LOTIS observation at early times
  38. GRB980613 Optical Observations
  39. GRB980703 (optical R observations)
  40. BeppoSAX NFI observations of GRB 980703
  41. GRB 980703: ASM Position & Intensity
  42. GRB980703 optical followup
  43. Radio observations of SGRs
  44. SGR1900+14 field optical observations
  45. GRB 980613: Optical transient and its host galaxy
  46. SGR1627-41, RXTE/ASM observations
  47. GRB 980613: Detection of the probable host galaxy
  48. GRB 980613 Optical Observations
  49. GRB 980613 optical observations
  50. Discovery of a new SGR source, SGR1627-41
  51. GRB980613 Optical Observations
  52. GRB980613 observations from Palomar
  53. GRB 980613 optical/IR obs.
  54. GRB980613 Near Infra-Red Observations
  55. GRB980613, BeppoSAX WFC positions
  56. GRB971214 Secondary Standards
  57. GRB980519 Secondary Standards
  58. SGR1900+14
  59. SGR1900+14
  60. BATSE on-board GRB trigger change
  61. GRB 980519 Optical Observations
  62. GRB 980519
  63. GRB980519 optical observations
  64. GRB 980519 Optical Observations
  65. GRB970519, optical follow-up at Schmidt Calern
  66. GRB980519 Optical Observations
  67. GRB 980519 Optical Observations
  68. GRB980519 optical observations
  69. GRB980515, BeppoSAX IAUC to be submitted
  70. BATSE on-board GRB trigger change
  71. GRB980515: SAX-WFC updated position
  72. BSAX Observations of GRB980425 field
  73. IPN web site of GRBs
  74. SAX J0840.7+2248 Optical Observations
  75. GRB980425: optical obs.
  76. GRB980425: Radio Observations
  77. report on BSAX observations of GRB980425
  78. GRB980326 X-ray Observations
  79. GRB980326, optical observations
  80. GRB980326, optical observations
  81. GRB980329 Keck K-band observations
  82. GRB980329 sub-millimeter observations
  83. GRB980326 optical observations
  84. GRB980329 optical observations
  85. GRB980329 VLA observations
  86. GRB980329 optical observations
  87. GRB980326 optical observations
  88. GRB970508 SAO RAS optical observations
  89. Optical Observations of GRB 970508
  90. Near-IR follow-up on GRB 971227
  91. Optical Observations of the GRB 971227 field
  92. Optical Observations on GRB 971227
  93. GRB971227: Plaskett R-band observations
  94. GRB 971227: Optical clarifications
  95. GRB971227: Further CAHA R-band images
  96. GRB971227: LOTIS observations
  97. GRB971214: Optical Observations and Calibrations
  98. GRB 971214: Optical Observations
  99. Radio Observations of GRB 971214 at the VLA
  100. GRB 971024: KPNO Optical Observations

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