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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"
  1. IPN triangulation of GRB001204 (short/hard)
  2. GRB 001105, further optical observations
  3. GRB001120: Gunn-i observations
  4. GRB001120: Optical observations
  5. GRB001109, optical observations
  6. GRB001120, optical observations
  7. WSRT 4.8 GHz observations of GRB001109
  8. IPN triangulation of GRB001120
  9. Optical/NIR observations of GRB001109
  10. GRB 001109: deep JHK upper limits
  11. GRB 001109 X-ray afterglow with BeppoSAX
  12. CORRECTION to XMM-Newton observation of GRB001025
  13. GRB001109: Optical observations
  14. GRB001109: BeppoSAX/NFI Observations
  15. GRB001109, R-band optical observations
  16. GRB001109, Radio observations
  17. GRB001109: BeppoSAX refined WFC position
  18. BeppoSAX ALERT: GRB001109
  19. GRB001105 BVRI field photometry correction
  20. GRB001105, BVRI field photometry
  21. GRB 001105, R-band observation
  22. IPN TRIANGULATION OF GRB001105
  23. GRB 001025B, Optical obervations
  24. GRB 991208: HST Imaging of the Host Galaxy
  25. GRB000926: R-image of the host galaxy
  26. GRB 001025B, I-band observations
  27. XMM-Newton observation of GRB001025
  28. GRB001025B, Radio observations
  29. GRB 001025 Optical Observations
  30. GRB 001025A, optical observation
  31. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  32. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  33. IPN triangulation of GRB001025
  34. GRB001007: Optical observations
  35. ASM Localization of GRB 001025
  36. GRB001007, Radio observations
  37. IPN TRIANGULATION OF GRB001020
  38. GRB001019, Optical Observations
  39. GRB 001018, Possible Radio Afterglow
  40. GRB001018, Gamma Ray Observations
  41. IPN TRIANGULATION OF GRB001019
  42. CORRECTION TO PEAK FLUX OF GRB001018
  43. IPN TRIANGULATION OF GRB001018
  44. IPN TRIANGULATION OF GRB 001017
  45. GRB 000926: Improved Absorber Redshift
  46. V,R,I band observations of GRB000926
  47. The Likely Optical/Infrared Afterglow of GRB 001011
  48. HETE positions added to GCN
  49. GRB001011 BeppoSAX/WFC refined position
  50. BeppoSAX ALERT: GRB001011
  51. GRB 001007, BVR-band observations
  52. GRB000926 - Amateur Optical Observations
  53. GRB001007: Optical observations
  54. CONCAM null result on GRB001005
  55. IPN triangulation of GRB001007
  56. GRB 000926 : the host galaxy
  57. HETE-2 Launches Successfully
  58. IPN triangulation of GRB001005
  59. HETE-2 48 hour Launch Delay
  60. GRB 000926 Chandra Observation
  61. IPN triangulation of GRB 001004
  62. Public availability of BeppoSAX data of GRB000926
  63. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  64. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  65. GRB000926 - Optical observations
  66. GRB000926 - Optical observations
  67. GRB 000926, Optical Decay
  68. GRB000911: VLT infrared observation
  69. GRB000926 - Optical observations
  70. GRB000926 - Optical observations
  71. GRB 000926: optical observations
  72. GRB 000926, Optical Observations
  73. GRB000926 - Optical observations
  74. GRB000911: optical VLT observations
  75. GRB000926 K'-band Observation
  76. GRB000926 : increasing optical decay slope
  77. GRB000926 optical observations
  78. GRB000926 - Optical observations
  79. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  80. J and K band observations of GRB 000926
  81. GRB000911 Optical Observations
  82. GRB 000926: Lightcurve Update and Predictions
  83. GRB 000926, optical observation by Oksanen (vsnet-grb)
  84. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  85. GRB000926: Optical observations
  86. CONCAM crude optical limits before and after GRB000926
  87. GRB 000926: Preliminary R-band Lightcurve
  88. GRB 000926 HST/Chandra TOO Status
  89. Spectroscopic Redshift of GRB 000926
  90. GRB 000926, Optical Observation
  91. GRB000926, radio observations
  92. GRB 000926: Optical candidate
  93. Optical candidate for GRB000926
  94. IPN triangulation of GRB000926
  95. IPN triangulation of GRB000926
  96. GRB 000911, BVRI field photometry
  97. GRB000911: Corrected coordinates
  98. GRB000911: Sub-millimeter observations
  99. IPN triangulation of GRB000925
  100. GRB000911: Optical Transient

Advanced

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