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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"

40645 results found.

  1. GRB001109: BeppoSAX/NFI Observations
  2. GRB001109, R-band optical observations
  3. GRB001109, Radio observations
  4. GRB001105, BVRI field photometry
  5. GRB 001105, R-band observation
  6. GRB 001025B, Optical obervations
  7. GRB 991208: HST Imaging of the Host Galaxy
  8. GRB000926: R-image of the host galaxy
  9. GRB 001025B, I-band observations
  10. XMM-Newton observation of GRB001025
  11. GRB001025B, Radio observations
  12. GRB 001025 Optical Observations
  13. GRB 001025A, optical observation
  14. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  15. GRB001007: Optical observations
  16. ASM Localization of GRB 001025
  17. GRB001007, Radio observations
  18. GRB001019, Optical Observations
  19. GRB 001018, Possible Radio Afterglow
  20. GRB001018, Gamma Ray Observations
  21. V,R,I band observations of GRB000926
  22. The Likely Optical/Infrared Afterglow of GRB 001011
  23. HETE positions added to GCN
  24. GRB 001007, BVR-band observations
  25. GRB000926 - Amateur Optical Observations
  26. GRB001007: Optical observations
  27. GRB 000926 : the host galaxy
  28. HETE-2 Launches Successfully
  29. GRB 000926 Chandra Observation
  30. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  31. GRB000926 - Optical observations
  32. GRB000926 - Optical observations
  33. GRB 000926, Optical Decay
  34. GRB000926 - Optical observations
  35. GRB000926 - Optical observations
  36. GRB 000926: optical observations
  37. GRB 000926, Optical Observations
  38. GRB000926 - Optical observations
  39. GRB000911: optical VLT observations
  40. GRB000926 K'-band Observation
  41. GRB000926 optical observations
  42. GRB000926 - Optical observations
  43. J and K band observations of GRB 000926
  44. GRB000911 Optical Observations
  45. GRB 000926: Lightcurve Update and Predictions
  46. GRB 000926, optical observation by Oksanen (vsnet-grb)
  47. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  48. GRB000926: Optical observations
  49. GRB 000926 HST/Chandra TOO Status
  50. Spectroscopic Redshift of GRB 000926
  51. GRB000926, radio observations
  52. GRB 000926: Optical candidate
  53. Optical candidate for GRB000926
  54. GRB 000911, BVRI field photometry
  55. GRB000911: Corrected coordinates
  56. GRB000911: Sub-millimeter observations
  57. GRB000911: Optical Transient
  58. GRB000911, Radio and Optical observations
  59. GRB000911, Radio observations
  60. GRB000911: Optical observations
  61. False GRB alarm from RXTE/ASM on 8 Sept 2000
  62. GRB 000830: Optical observations
  63. GRB000830: Optical observations
  64. GRB000830, TNG B-band observations
  65. GRB000830, BVRI field photometry
  66. GRB000830: Optical observations
  67. GRB000210, Optical observations
  68. Chandra Position of GRB000210
  69. "Snapshot" afterglow IDs and GRB 000830
  70. GRB000830: Optical observations
  71. IPN triangulation of GRB000830
  72. HST/STIS observations of the host galaxy of GRB 980329
  73. HST/STIS observations of the chaotic environment of GRB 980613
  74. SGR 1806-20 burst activity
  75. GRB000812, TNG R-band observations
  76. GRB000801 & GRB000730, Gamma Ray Observations
  77. GRB000730, Gamma Ray Observations
  78. GRB000812, Radio observations
  79. GRB000801, Gamma Ray Observations
  80. GRB000801, VLT-Antu R-band observations
  81. GRB000301C, UBVI optical observations
  82. GRB000801, Radio Observations
  83. GRB 991208 Host Galaxy Imaging
  84. GRB 990510: Possible detection of a host galaxy
  85. GRB 990510 Host Galaxy Discovery
  86. GRB 000727, optical observations
  87. GRB 990705, HST/STIS observations of the host galaxy
  88. GRB 990712: Late time HST/STIS Observations
  89. GRB 991216, HST/STIS observations
  90. GRB000620, Radio Observations
  91. GRB981226, HST/STIS observations of the host galaxy
  92. GRB000630, optical observations
  93. GRB 000630: Detection of the Optical Afterglow
  94. GRB000630, Revised BVRI Field Photometry
  95. GRB000630, Optical Observations
  96. GRB000630, optical observations
  97. GRB000630, optical observations
  98. GRB000630, BVRI Field Photometry
  99. GRB000630, optical observations
  100. GRB000630, optical observations

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