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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"

36146 results found.

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

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