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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"

35437 results found.

  1. IPN/RXTE TRIANGULATION OF GRB010126
  2. GRB010126: CONCAM crude optical limits during GRB
  3. GRB010126, TNG R-band observations
  4. IPN TRIANGULATION OF GRB010126
  5. IPN/RXTE TRIANGULATION OF GRB010126
  6. GRB 010119, optical observations
  7. GRB010119: Optical observations
  8. Optical Observations of GRB 001018 at Keck
  9. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  10. Optical observations of GRB 001018 with JCAM
  11. IPN TRIANGULATION OF GRB010115
  12. IPN TRIANGULATION OF GRB010109
  13. GRB010103, optical observations
  14. IPN triangulation of GRB010104
  15. IPN triangulation of GRB010103
  16. GRB 001204: Ks observations
  17. H band observation of GRB 001212
  18. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  19. IPN triangulation of GRB001219
  20. GRB 001212 Optical Observation
  21. GRB 001212 Optical Observation
  22. GRB 001212 optical observation
  23. GRB 001212 possible OA in 2MASS
  24. GRB 001212 possible OA
  25. IPN triangulation of GRB001212
  26. Confirmation of IPN position for GRB001204
  27. IPN triangulation of GRB001204 (short/hard)
  28. GRB 001105, further optical observations
  29. GRB001120: Gunn-i observations
  30. GRB001120: Optical observations
  31. GRB001109, optical observations
  32. GRB001120, optical observations
  33. IPN triangulation of GRB001120
  34. Optical/NIR observations of GRB001109
  35. GRB 001109: deep JHK upper limits
  36. GRB 001109 X-ray afterglow with BeppoSAX
  37. GRB001109: Optical observations
  38. GRB001109: BeppoSAX/NFI Observations
  39. GRB001109, R-band optical observations
  40. GRB001109, Radio observations
  41. BeppoSAX ALERT: GRB001109
  42. GRB001105 BVRI field photometry correction
  43. GRB001105, BVRI field photometry
  44. GRB 001105, R-band observation
  45. IPN TRIANGULATION OF GRB001105
  46. GRB 001025B, Optical obervations
  47. GRB 991208: HST Imaging of the Host Galaxy
  48. GRB000926: R-image of the host galaxy
  49. GRB 001025B, I-band observations
  50. GRB 001025 Optical Observations
  51. GRB 001025A, optical observation
  52. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  53. IPN triangulation of GRB001025
  54. ASM Localization of GRB 001025
  55. GRB001007, Radio observations
  56. IPN TRIANGULATION OF GRB001020
  57. GRB001019, Optical Observations
  58. GRB 001018, Possible Radio Afterglow
  59. GRB001018, Gamma Ray Observations
  60. IPN TRIANGULATION OF GRB001019
  61. IPN TRIANGULATION OF GRB001018
  62. IPN TRIANGULATION OF GRB 001017
  63. GRB 000926: Improved Absorber Redshift
  64. V,R,I band observations of GRB000926
  65. The Likely Optical/Infrared Afterglow of GRB 001011
  66. HETE positions added to GCN
  67. BeppoSAX ALERT: GRB001011
  68. GRB 001007, BVR-band observations
  69. GRB000926 - Amateur Optical Observations
  70. CONCAM null result on GRB001005
  71. IPN triangulation of GRB001007
  72. GRB 000926 : the host galaxy
  73. IPN triangulation of GRB001005
  74. GRB 000926 Chandra Observation
  75. IPN triangulation of GRB 001004
  76. Public availability of BeppoSAX data of GRB000926
  77. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  78. GRB 000926, Optical Decay
  79. GRB000926 - Optical observations
  80. GRB000926 - Optical observations
  81. GRB 000926: optical observations
  82. GRB 000926, Optical Observations
  83. GRB000926 K'-band Observation
  84. GRB000926 : increasing optical decay slope
  85. GRB000926 optical observations
  86. GRB000926 - Optical observations
  87. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  88. J and K band observations of GRB 000926
  89. GRB 000926: Lightcurve Update and Predictions
  90. GRB 000926, optical observation by Oksanen (vsnet-grb)
  91. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  92. CONCAM crude optical limits before and after GRB000926
  93. GRB 000926: Preliminary R-band Lightcurve
  94. GRB 000926 HST/Chandra TOO Status
  95. Spectroscopic Redshift of GRB 000926
  96. GRB 000926, Optical Observation
  97. GRB 000926: Optical candidate
  98. Optical candidate for GRB000926
  99. IPN triangulation of GRB000926
  100. GRB 000911, BVRI field photometry

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