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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"

37943 results found.

  1. GRB010213, Near-IR observations
  2. Possible InfraRed Transient of GRB 010214.
  3. GRB010214 Optical Observation
  4. GRB010214: BeppoSAX/NFI Observations
  5. GRB010213 (HETE) TAROT observations
  6. GRB 010214, optical observations
  7. BeppoSAX ALERT: GRB010214
  8. IPN Status Report
  9. HETE Status
  10. GRB010126 opt. obs.
  11. IPN/RXTE TRIANGULATION OF GRB010126
  12. GRB010126: CONCAM crude optical limits during GRB
  13. GRB010126, TNG R-band observations
  14. IPN TRIANGULATION OF GRB010126
  15. IPN/RXTE TRIANGULATION OF GRB010126
  16. GRB 010119, optical observations
  17. GRB010119: Optical observations
  18. Optical Observations of GRB 001018 at Keck
  19. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  20. Optical observations of GRB 001018 with JCAM
  21. IPN TRIANGULATION OF GRB010115
  22. IPN TRIANGULATION OF GRB010109
  23. GRB010103, optical observations
  24. IPN triangulation of GRB010104
  25. IPN triangulation of GRB010103
  26. GRB 001204: Ks observations
  27. H band observation of GRB 001212
  28. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  29. IPN triangulation of GRB001219
  30. GRB 001212 Optical Observation
  31. GRB 001212 Optical Observation
  32. GRB 001212 optical observation
  33. GRB 001212 possible OA in 2MASS
  34. GRB 001212 possible OA
  35. IPN triangulation of GRB001212
  36. Confirmation of IPN position for GRB001204
  37. IPN triangulation of GRB001204 (short/hard)
  38. GRB 001105, further optical observations
  39. GRB001120: Gunn-i observations
  40. GRB001120: Optical observations
  41. GRB001109, optical observations
  42. GRB001120, optical observations
  43. IPN triangulation of GRB001120
  44. Optical/NIR observations of GRB001109
  45. GRB 001109: deep JHK upper limits
  46. GRB 001109 X-ray afterglow with BeppoSAX
  47. GRB001109: Optical observations
  48. GRB001109: BeppoSAX/NFI Observations
  49. GRB001109, R-band optical observations
  50. GRB001109, Radio observations
  51. BeppoSAX ALERT: GRB001109
  52. GRB001105 BVRI field photometry correction
  53. GRB001105, BVRI field photometry
  54. GRB 001105, R-band observation
  55. IPN TRIANGULATION OF GRB001105
  56. GRB 001025B, Optical obervations
  57. GRB 991208: HST Imaging of the Host Galaxy
  58. GRB000926: R-image of the host galaxy
  59. GRB 001025B, I-band observations
  60. GRB 001025 Optical Observations
  61. GRB 001025A, optical observation
  62. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  63. IPN triangulation of GRB001025
  64. ASM Localization of GRB 001025
  65. GRB001007, Radio observations
  66. IPN TRIANGULATION OF GRB001020
  67. GRB001019, Optical Observations
  68. GRB 001018, Possible Radio Afterglow
  69. GRB001018, Gamma Ray Observations
  70. IPN TRIANGULATION OF GRB001019
  71. IPN TRIANGULATION OF GRB001018
  72. IPN TRIANGULATION OF GRB 001017
  73. GRB 000926: Improved Absorber Redshift
  74. V,R,I band observations of GRB000926
  75. The Likely Optical/Infrared Afterglow of GRB 001011
  76. HETE positions added to GCN
  77. BeppoSAX ALERT: GRB001011
  78. GRB 001007, BVR-band observations
  79. GRB000926 - Amateur Optical Observations
  80. CONCAM null result on GRB001005
  81. IPN triangulation of GRB001007
  82. GRB 000926 : the host galaxy
  83. IPN triangulation of GRB001005
  84. GRB 000926 Chandra Observation
  85. IPN triangulation of GRB 001004
  86. Public availability of BeppoSAX data of GRB000926
  87. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  88. GRB 000926, Optical Decay
  89. GRB000926 - Optical observations
  90. GRB000926 - Optical observations
  91. GRB 000926: optical observations
  92. GRB 000926, Optical Observations
  93. GRB000926 K'-band Observation
  94. GRB000926 : increasing optical decay slope
  95. GRB000926 optical observations
  96. GRB000926 - Optical observations
  97. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  98. J and K band observations of GRB 000926
  99. GRB 000926: Lightcurve Update and Predictions
  100. GRB 000926, optical observation by Oksanen (vsnet-grb)

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