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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"

24597 results found.

  1. GRB 981226 optical observations
  2. GRB981220 B, R and I band observations
  3. Optical Observations of GRB981226
  4. GRB 981220:Optical Observations
  5. GRB 981226 optical observations
  6. GRB 981220
  7. GRB 981220, radio observations
  8. GRB981220 I-band Observations
  9. GRB 981220
  10. GRB 980326/Host Galaxy
  11. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  12. BeppoSAX NFI Observation of GRB980425
  13. GRB980329 R,I flux calibration and R,I,K upper limits
  14. GRB980425 Optical Follow-up
  15. GRB 980923 BATSE Observations
  16. SGR1900+14, BeppoSAX-GRBM observations
  17. GRB970508 optical observations
  18. GRB971214, association with a Galactic star?
  19. GRB980519, Optical Observations
  20. GRB980703 - BeppoSAX/GRBM detection
  21. GRB980703 optical photometry
  22. GRB 980703: BATSE Observations
  23. GRB980703 optical observations
  24. GRB980703: Radio transient
  25. GRB 980703: Spectrum of the proposed optical counterpart
  26. GRB980703 Transient Optical Follow-Up
  27. GRB980703: LOTIS observation at early times
  28. GRB980613 Optical Observations
  29. GRB980703 (I band observations)
  30. BeppoSAX NFI observations of GRB 980703
  31. GRB980519 observation report
  32. GRB980703 optical followup
  33. Radio observations of SGRs
  34. SGR1900+14 field optical observations
  35. GRB980613, optical observations
  36. GRB 980613: Optical transient and its host galaxy
  37. SGR1627-41, RXTE/ASM observations
  38. GRB 980613: Detection of the probable host galaxy
  39. Reduced error box of SGR 1627-41
  40. GRB 980613: BATSE Observations
  41. GRB 980613 Optical Observations
  42. GRB 980613 optical observations
  43. Discovery of a new SGR source, SGR1627-41
  44. GRB980613 Optical Observations
  45. GRB980613 observations from Palomar
  46. GRB 980613 optical/IR obs.
  47. GRB980613 Near Infra-Red Observations
  48. GRB971214 Secondary Standards
  49. GRB980519 Secondary Standards
  50. BATSE on-board GRB trigger change
  51. GRB 980519 Optical Observations
  52. GRB 980519
  53. GRB980519 optical observations
  54. GRB 980519 Optical Observations
  55. GRB980519 BATSE Observations
  56. GRB980519 Optical Observations
  57. GRB980519 Optical Observations
  58. GRB 980519 Optical Observations
  59. GRB980515, BeppoSAX IAUC to be submitted
  60. BSAX Observations of GRB980425 field
  61. IPN web site of GRBs
  62. GRB980425 BATSE observations
  63. SAX J0840.7+2248 Optical Observations
  64. GRB980425: optical obs.
  65. GRB980425: Radio Observations
  66. report on BSAX observations of GRB980425
  67. GRB 980329 ROSAT observation
  68. GRB980326 X-ray Observations
  69. GRB980326, optical observations
  70. GRB980326, optical observations
  71. GRB980329, Fading IR counterpart to radio source
  72. GRB980329 Keck K-band observations
  73. GRB980329 sub-millimeter observations
  74. GRB980329 optical observations
  75. GRB980329 near-IR observations
  76. GRB980329 near-IR observations
  77. GRB980326 optical observations
  78. GRB980329 optical observations
  79. GRB980329 VLA observations
  80. GRB980329 optical observations
  81. GRB980329 optical observations
  82. GRB980326 optical observations
  83. GRB980326 optical observations
  84. Optical Observations of GRB 970508
  85. Near-IR follow-up on GRB 971227
  86. Optical Observations of the GRB 971227 field
  87. Optical Observations on GRB 971227
  88. GRB971227: Plaskett R-band observations
  89. GRB 971227: Optical clarifications
  90. GRB971227: Further CAHA R-band images
  91. GRB971227: LOTIS observations
  92. GRB971214: Optical Observations and Calibrations
  93. GRB 971214: Optical Observations
  94. Radio Observations of GRB 971214 at the VLA
  95. GRB 971024: Refined analysis by USNOFS Observations
  96. GRB 971024: KPNO Optical Observations
  97. GRB 970828: Palomar Observations

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