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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"

36789 results found.

  1. IPN TRIANGULATION OF GRB001105
  2. GRB 001025B, Optical obervations
  3. GRB 991208: HST Imaging of the Host Galaxy
  4. GRB000926: R-image of the host galaxy
  5. GRB 001025B, I-band observations
  6. GRB 001025 Optical Observations
  7. GRB 001025A, optical observation
  8. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  9. IPN triangulation of GRB001025
  10. ASM Localization of GRB 001025
  11. GRB001007, Radio observations
  12. IPN TRIANGULATION OF GRB001020
  13. GRB001019, Optical Observations
  14. GRB 001018, Possible Radio Afterglow
  15. GRB001018, Gamma Ray Observations
  16. IPN TRIANGULATION OF GRB001019
  17. IPN TRIANGULATION OF GRB001018
  18. IPN TRIANGULATION OF GRB 001017
  19. GRB 000926: Improved Absorber Redshift
  20. V,R,I band observations of GRB000926
  21. The Likely Optical/Infrared Afterglow of GRB 001011
  22. HETE positions added to GCN
  23. BeppoSAX ALERT: GRB001011
  24. GRB 001007, BVR-band observations
  25. GRB000926 - Amateur Optical Observations
  26. CONCAM null result on GRB001005
  27. IPN triangulation of GRB001007
  28. GRB 000926 : the host galaxy
  29. IPN triangulation of GRB001005
  30. GRB 000926 Chandra Observation
  31. IPN triangulation of GRB 001004
  32. Public availability of BeppoSAX data of GRB000926
  33. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  34. GRB 000926, Optical Decay
  35. GRB000926 - Optical observations
  36. GRB000926 - Optical observations
  37. GRB 000926: optical observations
  38. GRB 000926, Optical Observations
  39. GRB000926 K'-band Observation
  40. GRB000926 : increasing optical decay slope
  41. GRB000926 optical observations
  42. GRB000926 - Optical observations
  43. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  44. J and K band observations of GRB 000926
  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. CONCAM crude optical limits before and after GRB000926
  49. GRB 000926: Preliminary R-band Lightcurve
  50. GRB 000926 HST/Chandra TOO Status
  51. Spectroscopic Redshift of GRB 000926
  52. GRB 000926, Optical Observation
  53. GRB 000926: Optical candidate
  54. Optical candidate for GRB000926
  55. IPN triangulation of GRB000926
  56. GRB 000911, BVRI field photometry
  57. GRB000911: Sub-millimeter observations
  58. IPN triangulation of GRB000925
  59. IPN triangulation of GRB000911
  60. IPN triangulation of GRB000910
  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. IPN triangulation of GRB000830
  71. HST/STIS observations of the host galaxy of GRB 980329
  72. HST/STIS observations of the chaotic environment of GRB 980613
  73. IPN localization of GRB000820
  74. GRB000801 & GRB000730, Gamma Ray Observations
  75. GRB000730, Gamma Ray Observations
  76. GRB000812, Radio observations
  77. IPN localization of GRB000812
  78. IPN localization of GRB000811
  79. GRB000801, Gamma Ray Observations
  80. GRB000801, VLT-Antu R-band observations
  81. GRB 991208 Host Galaxy Imaging
  82. Updated IPN coordinates for GRB000801
  83. IPN localization of GRB000801
  84. IPN localization of GRB000730B
  85. IPN localization of GRB000730B
  86. IPN localization of GRB000730
  87. GRB 990510: Possible detection of a host galaxy
  88. GRB 990510 Host Galaxy Discovery
  89. GRB 000727, optical observations
  90. IPN localization of GRB000727
  91. GRB 990705, HST/STIS observations of the host galaxy
  92. GRB 990712: Late time HST/STIS Observations
  93. GRB 991216, HST/STIS observations
  94. GRB981226, HST/STIS observations of the host galaxy
  95. GRB 000630: Detection of the Optical Afterglow
  96. GRB000630, Revised BVRI Field Photometry
  97. GRB000630, Optical Observations
  98. GRB000630, optical observations
  99. GRB000630, BVRI Field Photometry
  100. GRB000630, optical observations

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