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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"

41675 results found.

  1. GRB000607, optical observations
  2. GRB 000615: NIR further observations
  3. BeppoSAX ALERT: GRB000620
  4. GRB000620: BeppoSAX Alert
  5. GRB990123, HST/STIS observations of the host galaxy
  6. GRB000616 optical observations
  7. GRB 000615, near-infrared observations
  8. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  9. GRB000616 [IPN Position]
  10. GRB000615B [IPN Position]
  11. GRB000615, further R-band photometry
  12. GRB 000615: NIR observations
  13. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  14. GRB000615, R-band photometry
  15. GRB980425, HST/STIS observations of the host galaxy
  16. GRB000615: BeppoSAX GRB Alert
  17. The Hosts of GRB 980703 and GRB 971214
  18. GRB 000301C: Further Late-Time HST/STIS observations
  19. GRB000528: follow-up X-ray measurements and update of IPN annulus
  20. Optical Follow-up of GRB000529 Error Box
  21. GRB980519, HST/STIS observations of the host galaxy
  22. GRB000607, Radio Observations
  23. BeppoSAX X-ray transient/possible GRB000608
  24. GRB000604 optical non-detection
  25. GRB000604 - Optical observations
  26. GRB000607, A SHORT, HARD BURST
  27. GRB000604, optical observations
  28. GRB000528, optical observations at ESO
  29. GRB 000604 optical observations
  30. GRB 000418: Detection of the Host Galaxy
  31. GRB000604, optical observations, comparison with DPOSS
  32. GRB000604 [IPN Position]
  33. GRB000528, Radio Observations
  34. X-ray Afterglow of GRB 000529
  35. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  36. GRB000529: Optical Observations
  37. IPN localization and time history of GRB000528
  38. New IPN localization of GRB000529
  39. GRB000519: Optical observations
  40. IPN localization of GRB000529
  41. GRB 000528 - WFC measurements
  42. GRB000529: BeppoSAX WFC position
  43. GRB000528: BeppoSAX GRBM observations
  44. GRB 000528 Optical Observations
  45. GRB000519, BVRI field photometry
  46. IPN triangulation of GRB000519
  47. IPN triangulation of GRB000516
  48. Re: GRB000508B : Optical observations
  49. GRB 000418, Optical observation
  50. GRB000508B, optical photometry
  51. GRB000508B, BVR field photometry
  52. Possible GRB-related phenomenon
  53. RXTE/ASM and IPN localization of GRB 000508B
  54. GRB000424, UBVRI field photometry
  55. GRB 000424 Optical Observations
  56. GRB000418, UBVRI field photometry update
  57. The redshift of GRB 000418
  58. GRB000424, optical observations
  59. GRB 000429, optical observation
  60. GRB 000429, UBVRI field photometry
  61. IPN localization of GRB000429
  62. GRB 000418, UBVRI field photometry
  63. GRB000418, Radio detection
  64. GRB000418, K'-band photometry
  65. GRB 000418, optical observation
  66. GRB000424 Optical Observations
  67. GRB 000418, Optical Observation
  68. GRB000424, optical observations
  69. GRB000424, optical observations
  70. GRB 000424, Optical Observations
  71. GRB000418, near-infrared observations
  72. BeppoSAX GRB000424
  73. Correction to IPN error box for GRB000419
  74. IPN error box for GRB000418
  75. GRB000419 [IPN Position]
  76. GRB000416 Optical Observations
  77. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  78. GRB000416 BRJK observations
  79. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  80. GRB 000408, optical observations
  81. Refined IPN error box for GRB000408
  82. GRB 991208, UBVRI field photometry
  83. GRB000301c results
  84. GRB000408: Optical CCD Observations from MIRO
  85. GRB000408, lotis optical observations
  86. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  87. GRB000408 [IPN Position]
  88. GRB000326 Optical Observations
  89. GRB000301C - R magnitude lower limit
  90. GRB 000323, optical observations
  91. GRB 000326: Optical Observations
  92. GRB000326, Radio observations
  93. GRB000326 [IPN Position]
  94. GRB 000307 optical observations
  95. GRB000323 [IPN Position]
  96. Single error box for GRB000315
  97. GRB000315 [IPN Positions]
  98. GRB000313, Radio observations
  99. GRB 000313 - optical transient in the BATSE error box
  100. GRB000301C - B and R photometry

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