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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"

44399 results found.

  1. GRB 000615: NIR observations
  2. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  3. GRB000615, R-band photometry
  4. GRB000615: BeppoSAX refined coordinates
  5. GRB980425, HST/STIS observations of the host galaxy
  6. GRB000615: BeppoSAX GRB Alert
  7. The Hosts of GRB 980703 and GRB 971214
  8. GRB 000301C: Further Late-Time HST/STIS observations
  9. GRB000528: follow-up X-ray measurements and update of IPN annulus
  10. Optical Follow-up of GRB000529 Error Box
  11. GRB980519, HST/STIS observations of the host galaxy
  12. GRB000607, Radio Observations
  13. BeppoSAX X-ray transient/possible GRB000608
  14. GRB000604 optical non-detection
  15. GRB000604 - Optical observations
  16. GRB000607, A SHORT, HARD BURST
  17. GRB000604, optical observations
  18. GRB000528, optical observations at ESO
  19. GRB 000604 optical observations
  20. GRB 000418: Detection of the Host Galaxy
  21. GRB000604, optical observations, comparison with DPOSS
  22. GRB000604 [IPN Position]
  23. GRB000528, Radio Observations
  24. X-ray Afterglow of GRB 000529
  25. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  26. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  27. GRB000529: Optical Observations
  28. IPN localization and time history of GRB000528
  29. New IPN localization of GRB000529
  30. GRB000519: Optical observations
  31. IPN localization of GRB000529
  32. GRB 000528 - WFC measurements
  33. GRB000529: BeppoSAX WFC position
  34. GRB000528: BeppoSAX GRBM observations
  35. GRB 000528 Optical Observations
  36. GRB000519, BVRI field photometry
  37. IPN triangulation of GRB000519
  38. IPN triangulation of GRB000516
  39. Re: GRB000508B : Optical observations
  40. GRB 000418, Optical observation
  41. GRB000508B, optical photometry
  42. GRB000508B, BVR field photometry
  43. Possible GRB-related phenomenon
  44. RXTE/ASM and IPN localization of GRB 000508B
  45. GRB000424, UBVRI field photometry
  46. GRB 000424 Optical Observations
  47. GRB000418, UBVRI field photometry update
  48. The redshift of GRB 000418
  49. GRB000424, optical observations
  50. GRB 000429, optical observation
  51. GRB 000429, UBVRI field photometry
  52. IPN localization of GRB000429
  53. GRB 000418, UBVRI field photometry
  54. GRB000418, Radio detection
  55. GRB000418, K'-band photometry
  56. GRB 000418, Optical Observation
  57. GRB 000418, optical observation
  58. GRB000424 Optical Observations
  59. GRB 000418, Optical Observation
  60. GRB000424, optical observations
  61. GRB000424, optical observations
  62. GRB 000424, Optical Observations
  63. GRB 000418, Optical Observation
  64. GRB000418, near-infrared observations
  65. BeppoSAX GRB000424
  66. Correction to IPN error box for GRB000419
  67. IPN error box for GRB000418
  68. GRB000419 [IPN Position]
  69. GRB000416 Optical Observations
  70. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  71. GRB000416 BRJK observations
  72. 1SAXJ1715.0-7134 refined position
  73. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  74. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  75. Budget cuts in BeppoSAX operations: impact on GRB observations
  76. GRB 000408, optical observations
  77. Refined IPN error box for GRB000408
  78. GRB 991208, UBVRI field photometry
  79. GRB000301c results
  80. GRB000408: Optical CCD Observations from MIRO
  81. GRB000408, lotis optical observations
  82. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  83. GRB000408 [IPN Position]
  84. GRB000326 Optical Observations
  85. GRB000301C - Addendum to GCN 623
  86. GRB000301C - R magnitude lower limit
  87. GRB000326, Further VLA observations
  88. GRB 000323, optical observations
  89. GRB 000326: Optical Observations
  90. GRB000326, Radio observations
  91. GRB000326 [IPN Position]
  92. GRB 000307 optical observations
  93. GRB000323 [IPN Position]
  94. Single error box for GRB000315
  95. GRB000315 [IPN Positions]
  96. GRB000313, Radio observations
  97. GRB 000313 - optical transient in the BATSE error box
  98. GRB000301C - B and R photometry
  99. GRB000301C - R photometry
  100. GRB 000307, Optical Observations

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