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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"

38344 results found.

  1. GRB010126, TNG R-band observations
  2. IPN TRIANGULATION OF GRB010126
  3. IPN/RXTE TRIANGULATION OF GRB010126
  4. GRB 010119, optical observations
  5. GRB010119: Optical observations
  6. Optical Observations of GRB 001018 at Keck
  7. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  8. Optical observations of GRB 001018 with JCAM
  9. IPN TRIANGULATION OF GRB010115
  10. IPN TRIANGULATION OF GRB010109
  11. GRB010103, optical observations
  12. IPN triangulation of GRB010104
  13. IPN triangulation of GRB010103
  14. GRB 001204: Ks observations
  15. H band observation of GRB 001212
  16. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  17. IPN triangulation of GRB001219
  18. GRB 001212 Optical Observation
  19. GRB 001212 Optical Observation
  20. GRB 001212 optical observation
  21. GRB 001212 possible OA in 2MASS
  22. GRB 001212 possible OA
  23. IPN triangulation of GRB001212
  24. Confirmation of IPN position for GRB001204
  25. IPN triangulation of GRB001204 (short/hard)
  26. GRB 001105, further optical observations
  27. GRB001120: Gunn-i observations
  28. GRB001120: Optical observations
  29. GRB001109, optical observations
  30. GRB001120, optical observations
  31. WSRT 4.8 GHz observations of GRB001109
  32. IPN triangulation of GRB001120
  33. Optical/NIR observations of GRB001109
  34. GRB 001109: deep JHK upper limits
  35. GRB 001109 X-ray afterglow with BeppoSAX
  36. GRB001109: Optical observations
  37. GRB001109: BeppoSAX/NFI Observations
  38. GRB001109, R-band optical observations
  39. GRB001109, Radio observations
  40. BeppoSAX ALERT: GRB001109
  41. GRB001105 BVRI field photometry correction
  42. GRB001105, BVRI field photometry
  43. GRB 001105, R-band observation
  44. IPN TRIANGULATION OF GRB001105
  45. GRB 001025B, Optical obervations
  46. GRB 991208: HST Imaging of the Host Galaxy
  47. GRB000926: R-image of the host galaxy
  48. GRB 001025B, I-band observations
  49. GRB 001025 Optical Observations
  50. GRB 001025A, optical observation
  51. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  52. IPN triangulation of GRB001025
  53. ASM Localization of GRB 001025
  54. GRB001007, Radio observations
  55. IPN TRIANGULATION OF GRB001020
  56. GRB001019, Optical Observations
  57. GRB 001018, Possible Radio Afterglow
  58. GRB001018, Gamma Ray Observations
  59. IPN TRIANGULATION OF GRB001019
  60. IPN TRIANGULATION OF GRB001018
  61. IPN TRIANGULATION OF GRB 001017
  62. GRB 000926: Improved Absorber Redshift
  63. V,R,I band observations of GRB000926
  64. The Likely Optical/Infrared Afterglow of GRB 001011
  65. HETE positions added to GCN
  66. BeppoSAX ALERT: GRB001011
  67. GRB 001007, BVR-band observations
  68. GRB000926 - Amateur Optical Observations
  69. GRB001007: 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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