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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"

35941 results found.

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

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