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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"

38358 results found.

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

Advanced

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