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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"

37734 results found.

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

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