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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"
  1. GRB990308, HST/STIS observations of the host galaxy
  2. GRB000620 - Optical observations
  3. GRB000620 Optical observations
  4. IPN annulus for GRB000620
  5. GRB000620: BeppoSAX WFC and GRBM detection
  6. GRB000615, Radio observations
  7. GRB000607, optical observations
  8. GRB 000615: NIR further observations
  9. GRB000620: refined BeppoSAX/WFC coordinates
  10. BeppoSAX ALERT: GRB000620
  11. GRB000620: BeppoSAX Alert
  12. GRB990123, HST/STIS observations of the host galaxy
  13. GRB000616 optical observations
  14. GRB 000615, near-infrared observations
  15. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  16. GRB000616 [IPN Position]
  17. GRB000615B [IPN Position]
  18. GRB000615, further R-band photometry
  19. GRB 000615: NIR observations
  20. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  21. GRB000615, R-band photometry
  22. GRB000615: BeppoSAX refined coordinates
  23. GRB980425, HST/STIS observations of the host galaxy
  24. GRB000615: BeppoSAX GRB Alert
  25. The Hosts of GRB 980703 and GRB 971214
  26. GRB 000301C: Further Late-Time HST/STIS observations
  27. GRB000528: follow-up X-ray measurements and update of IPN annulus
  28. Optical Follow-up of GRB000529 Error Box
  29. GRB980519, HST/STIS observations of the host galaxy
  30. GRB000607, Radio Observations
  31. BeppoSAX X-ray transient/possible GRB000608
  32. GRB000604 optical non-detection
  33. GRB000604 - Optical observations
  34. GRB000607, A SHORT, HARD BURST
  35. GRB000604, optical observations
  36. GRB000528, optical observations at ESO
  37. GRB 000604 optical observations
  38. GRB 000418: Detection of the Host Galaxy
  39. GRB000604, optical observations, comparison with DPOSS
  40. GRB000604 [IPN Position]
  41. GRB000528, Radio Observations
  42. X-ray Afterglow of GRB 000529
  43. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  44. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  45. GRB000529: Optical Observations
  46. IPN localization and time history of GRB000528
  47. New IPN localization of GRB000529
  48. GRB000519: Optical observations
  49. IPN localization of GRB000529
  50. GRB 000528 - WFC measurements
  51. GRB000529: BeppoSAX WFC position
  52. GRB000528: BeppoSAX GRBM observations
  53. GRB 000528 Optical Observations
  54. GRB000519, BVRI field photometry
  55. IPN triangulation of GRB000519
  56. IPN triangulation of GRB000516
  57. Re: GRB000508B : Optical observations
  58. GRB 000418, Optical observation
  59. GRB000508B, optical photometry
  60. GRB000508B, BVR field photometry
  61. Possible GRB-related phenomenon
  62. RXTE/ASM and IPN localization of GRB 000508B
  63. GRB000424, UBVRI field photometry
  64. GRB 000424 Optical Observations
  65. GRB000418, UBVRI field photometry update
  66. The redshift of GRB 000418
  67. GRB000424, optical observations
  68. GRB 000429, optical observation
  69. GRB 000429, UBVRI field photometry
  70. IPN localization of GRB000429
  71. GRB 000418, UBVRI field photometry
  72. GRB000418, Radio detection
  73. GRB000418, K'-band photometry
  74. GRB 000418, Optical Observation
  75. GRB 000418, optical observation
  76. GRB000424 Optical Observations
  77. GRB 000418, Optical Observation
  78. GRB000424, optical observations
  79. GRB000424, optical observations
  80. GRB 000424, Optical Observations
  81. GRB 000418, Optical Observation
  82. GRB000418, near-infrared observations
  83. BeppoSAX GRB000424
  84. Correction to IPN error box for GRB000419
  85. IPN error box for GRB000418
  86. GRB000419 [IPN Position]
  87. GRB000416 Optical Observations
  88. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  89. GRB000416 BRJK observations
  90. 1SAXJ1715.0-7134 refined position
  91. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  92. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  93. Budget cuts in BeppoSAX operations: impact on GRB observations
  94. GRB 000408, optical observations
  95. Refined IPN error box for GRB000408
  96. GRB 991208, UBVRI field photometry
  97. GRB000301c results
  98. GRB000408: Optical CCD Observations from MIRO
  99. GRB000408, lotis optical observations
  100. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field

Advanced

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