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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').

3410 results found.

  1. Probable SGR or Short Duration GRB Detected by HETE
  2. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  3. GRB 010629 Optical Observations
  4. GRB010629: A Burst Localized by HETE
  5. Possible burst from SGR1806-20
  6. IPN detection of SGR1900+14
  7. X-ray precursors to the large flare from SGR 1900+14
  8. SGR 1900+14: No evidence of extended X-ray emission
  9. SGR 1900+14 : RXTE observations
  10. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  11. SGR1900+14
  12. SGR 1900+14: Correction to GCN 1049
  13. Millimeter observation of SGR 1900+14
  14. SGR 1900+14: Detection of extended X-ray emission
  15. Chandra Observations of SGR 1900+14
  16. SGR 1900+14, Chandra observations
  17. Chandra Observations of SGR 1900+14
  18. SGR1900+14, I-band observations
  19. GRB 980326: Late-time HST/STIS observations
  20. GRB 010214, I-band data
  21. GRB010214 Optical Observation
  22. GRB010126 optical observations
  23. Optical Observations of GRB 001018 at Keck
  24. IPN triangulation of GRB001219
  25. GRB 001109: deep JHK upper limits
  26. IPN TRIANGULATION OF GRB001105
  27. IPN TRIANGULATION OF GRB001020
  28. GRB 000926 Chandra Observation
  29. GRB000926 K'-band Observation
  30. HST/STIS observations of the host galaxy of GRB 980329
  31. SGR 1806-20 burst activity
  32. IPN localization of GRB000730B
  33. IPN localization of GRB000730B
  34. GRB 990510: Possible detection of a host galaxy
  35. GRB 990510 Host Galaxy Discovery
  36. GRB 990712: Late time HST/STIS Observations
  37. GRB 000630: Detection of the Optical Afterglow
  38. GRB000616 [IPN Position]
  39. GRB 000418: Detection of the Host Galaxy
  40. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  41. GRB000529: BeppoSAX WFC position
  42. GRB000528: BeppoSAX GRBM observations
  43. GRB000419 [IPN Position]
  44. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  45. GRB 000326: Optical Observations
  46. GRB 000301C, Optical Observation
  47. GRB000301C
  48. GRB 000301C : Optical Candidate
  49. GRB000226 [IPN Position]
  50. HST Observations of GRB 990712
  51. IPN annulus for GRB000214
  52. GRB000126, optical observations
  53. IPN localization of GRB000126
  54. GRB991216 late optical observation
  55. BEPPOSAX GRBM Localization of GRB991226
  56. IPN error boxes for GRB991229
  57. IPN localization of GRB991226
  58. IPN localization of GRB991208
  59. IPN localization of GRB991014 - CORRECTION
  60. IPN localization of GRB991014
  61. BATSE GRB trigger criteria
  62. GRB 990712 Late Optical Decay and Host Galaxy
  63. GRB 990712, Optical Observation
  64. GRB 990712
  65. IPN localization of GRB990705
  66. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  67. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  68. GRB 990510: optical observations
  69. GRB 990510: optical observations
  70. GRB990510: X-ray afterglow
  71. GRB 990510: optical observation
  72. GRB 990510: Broad Band Break
  73. GRB990510: optical observation
  74. GRB 990510 Optical Observations
  75. GRB 990510 optical observations
  76. GRB990510 optical observations
  77. GRB990510
  78. GRB 990510 optical observations
  79. GRB 990510 optical observations
  80. GRB 990510 optical observations
  81. IPN localization of GRB990510
  82. New IPN/RXTE error box for GRB990506
  83. GRB990308 not a new SGR
  84. GRB990308, Possible new SGR~0209+70
  85. GRB 990123: Discovery of the Probable Host Galaxy
  86. Possible identification of SN1999E with GRB980910
  87. GRB 981226: radio variable
  88. GRB 981226 Optical Observations
  89. GRB981226, sub-millimeter observations
  90. GRB 981226
  91. GRB 981226 optical observations
  92. Optical Observations of GRB981226
  93. GRB 981226 - Infrared Observations
  94. SGR1900+14, BeppoSAX-GRBM observations
  95. SGR1627-41
  96. SGR1627-41, RXTE/ASM observations
  97. Reduced error box of SGR 1627-41
  98. SGR 1627-41
  99. Discovery of a new SGR source, SGR1627-41
  100. GRB980613 observations from Palomar

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