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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"

37520 results found.

  1. IPN triangulation of GRB010104
  2. IPN triangulation of GRB010103
  3. GRB 001204: Ks observations
  4. H band observation of GRB 001212
  5. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  6. IPN triangulation of GRB001219
  7. GRB 001212 Optical Observation
  8. GRB 001212 Optical Observation
  9. GRB 001212 optical observation
  10. GRB 001212 possible OA in 2MASS
  11. GRB 001212 possible OA
  12. IPN triangulation of GRB001212
  13. Confirmation of IPN position for GRB001204
  14. IPN triangulation of GRB001204 (short/hard)
  15. GRB 001105, further optical observations
  16. GRB001120: Gunn-i observations
  17. GRB001120: Optical observations
  18. GRB001109, optical observations
  19. GRB001120, optical observations
  20. IPN triangulation of GRB001120
  21. Optical/NIR observations of GRB001109
  22. GRB 001109: deep JHK upper limits
  23. GRB 001109 X-ray afterglow with BeppoSAX
  24. GRB001109: Optical observations
  25. GRB001109: BeppoSAX/NFI Observations
  26. GRB001109, R-band optical observations
  27. GRB001109, Radio observations
  28. BeppoSAX ALERT: GRB001109
  29. GRB001105 BVRI field photometry correction
  30. GRB001105, BVRI field photometry
  31. GRB 001105, R-band observation
  32. IPN TRIANGULATION OF GRB001105
  33. GRB 001025B, Optical obervations
  34. GRB 991208: HST Imaging of the Host Galaxy
  35. GRB000926: R-image of the host galaxy
  36. GRB 001025B, I-band observations
  37. GRB 001025 Optical Observations
  38. GRB 001025A, optical observation
  39. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  40. IPN triangulation of GRB001025
  41. ASM Localization of GRB 001025
  42. GRB001007, Radio observations
  43. IPN TRIANGULATION OF GRB001020
  44. GRB001019, Optical Observations
  45. GRB 001018, Possible Radio Afterglow
  46. GRB001018, Gamma Ray Observations
  47. IPN TRIANGULATION OF GRB001019
  48. IPN TRIANGULATION OF GRB001018
  49. IPN TRIANGULATION OF GRB 001017
  50. GRB 000926: Improved Absorber Redshift
  51. V,R,I band observations of GRB000926
  52. The Likely Optical/Infrared Afterglow of GRB 001011
  53. HETE positions added to GCN
  54. BeppoSAX ALERT: GRB001011
  55. GRB 001007, BVR-band observations
  56. GRB000926 - Amateur Optical Observations
  57. CONCAM null result on GRB001005
  58. IPN triangulation of GRB001007
  59. GRB 000926 : the host galaxy
  60. IPN triangulation of GRB001005
  61. GRB 000926 Chandra Observation
  62. IPN triangulation of GRB 001004
  63. Public availability of BeppoSAX data of GRB000926
  64. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  65. GRB 000926, Optical Decay
  66. GRB000926 - Optical observations
  67. GRB000926 - Optical observations
  68. GRB 000926: optical observations
  69. GRB 000926, Optical Observations
  70. GRB000926 K'-band Observation
  71. GRB000926 : increasing optical decay slope
  72. GRB000926 optical observations
  73. GRB000926 - Optical observations
  74. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  75. J and K band observations of GRB 000926
  76. GRB 000926: Lightcurve Update and Predictions
  77. GRB 000926, optical observation by Oksanen (vsnet-grb)
  78. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  79. CONCAM crude optical limits before and after GRB000926
  80. GRB 000926: Preliminary R-band Lightcurve
  81. GRB 000926 HST/Chandra TOO Status
  82. Spectroscopic Redshift of GRB 000926
  83. GRB 000926, Optical Observation
  84. GRB 000926: Optical candidate
  85. Optical candidate for GRB000926
  86. IPN triangulation of GRB000926
  87. GRB 000911, BVRI field photometry
  88. GRB000911: Sub-millimeter observations
  89. IPN triangulation of GRB000925
  90. IPN triangulation of GRB000911
  91. IPN triangulation of GRB000910
  92. False GRB alarm from RXTE/ASM on 8 Sept 2000
  93. GRB 000830: Optical observations
  94. GRB000830: Optical observations
  95. GRB000830, TNG B-band observations
  96. GRB000830, BVRI field photometry
  97. GRB000830: Optical observations
  98. GRB000210, Optical observations
  99. Chandra Position of GRB000210
  100. "Snapshot" afterglow IDs and GRB 000830

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