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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"

37101 results found.

  1. GRB001018, Gamma Ray Observations
  2. IPN TRIANGULATION OF GRB001019
  3. IPN TRIANGULATION OF GRB001018
  4. IPN TRIANGULATION OF GRB 001017
  5. GRB 000926: Improved Absorber Redshift
  6. V,R,I band observations of GRB000926
  7. The Likely Optical/Infrared Afterglow of GRB 001011
  8. HETE positions added to GCN
  9. BeppoSAX ALERT: GRB001011
  10. GRB 001007, BVR-band observations
  11. GRB000926 - Amateur Optical Observations
  12. CONCAM null result on GRB001005
  13. IPN triangulation of GRB001007
  14. GRB 000926 : the host galaxy
  15. HETE-2 Launches Successfully
  16. IPN triangulation of GRB001005
  17. GRB 000926 Chandra Observation
  18. IPN triangulation of GRB 001004
  19. Public availability of BeppoSAX data of GRB000926
  20. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  21. GRB 000926, Optical Decay
  22. GRB000926 - Optical observations
  23. GRB000926 - Optical observations
  24. GRB 000926: optical observations
  25. GRB 000926, Optical Observations
  26. GRB000926 K'-band Observation
  27. GRB000926 : increasing optical decay slope
  28. GRB000926 optical observations
  29. GRB000926 - Optical observations
  30. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  31. J and K band observations of GRB 000926
  32. GRB 000926: Lightcurve Update and Predictions
  33. GRB 000926, optical observation by Oksanen (vsnet-grb)
  34. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  35. CONCAM crude optical limits before and after GRB000926
  36. GRB 000926: Preliminary R-band Lightcurve
  37. GRB 000926 HST/Chandra TOO Status
  38. Spectroscopic Redshift of GRB 000926
  39. GRB 000926, Optical Observation
  40. GRB 000926: Optical candidate
  41. Optical candidate for GRB000926
  42. IPN triangulation of GRB000926
  43. GRB 000911, BVRI field photometry
  44. GRB000911: Sub-millimeter observations
  45. IPN triangulation of GRB000925
  46. IPN triangulation of GRB000911
  47. IPN triangulation of GRB000910
  48. False GRB alarm from RXTE/ASM on 8 Sept 2000
  49. GRB 000830: Optical observations
  50. GRB000830: Optical observations
  51. GRB000830, TNG B-band observations
  52. GRB000830, BVRI field photometry
  53. GRB000830: Optical observations
  54. GRB000210, Optical observations
  55. Chandra Position of GRB000210
  56. "Snapshot" afterglow IDs and GRB 000830
  57. IPN triangulation of GRB000830
  58. HST/STIS observations of the host galaxy of GRB 980329
  59. HST/STIS observations of the chaotic environment of GRB 980613
  60. IPN localization of GRB000820
  61. GRB000801 & GRB000730, Gamma Ray Observations
  62. GRB000730, Gamma Ray Observations
  63. GRB000812, Radio observations
  64. IPN localization of GRB000812
  65. IPN localization of GRB000811
  66. GRB000801, Gamma Ray Observations
  67. GRB000801, VLT-Antu R-band observations
  68. GRB 991208 Host Galaxy Imaging
  69. Updated IPN coordinates for GRB000801
  70. IPN localization of GRB000801
  71. IPN localization of GRB000730B
  72. IPN localization of GRB000730B
  73. IPN localization of GRB000730
  74. GRB 990510: Possible detection of a host galaxy
  75. GRB 990510 Host Galaxy Discovery
  76. GRB 000727, optical observations
  77. IPN localization of GRB000727
  78. GRB 990705, HST/STIS observations of the host galaxy
  79. GRB 990712: Late time HST/STIS Observations
  80. GRB 991216, HST/STIS observations
  81. GRB981226, HST/STIS observations of the host galaxy
  82. GRB 000630: Detection of the Optical Afterglow
  83. GRB000630, Revised BVRI Field Photometry
  84. GRB000630, Optical Observations
  85. GRB000630, optical observations
  86. GRB000630, BVRI Field Photometry
  87. GRB000630, optical observations
  88. GRB000630: Optical observations
  89. GRB000630, Radio Observations
  90. possible optical counterpart of GRB 000630
  91. IPN triangulation of GRB000630
  92. GRB 000623, optical observations
  93. GRB 000620, optical observations
  94. GRB000418, HST/STIS Observations
  95. GRB990123: Late-time HST/STIS observations of the host
  96. GRB 990506, HST/STIS Observations of the Host Galaxy
  97. GRB000623
  98. GRB 000620: J-band observations
  99. GRB000615: H-band observations
  100. GRB990308, HST/STIS observations of the host galaxy

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