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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"

24375 results found.

  1. GRB001018, Gamma Ray Observations
  2. V,R,I band observations of GRB000926
  3. HETE positions added to GCN
  4. GRB000926 - Amateur Optical Observations
  5. CONCAM null result on GRB001005
  6. GRB 000926 : the host galaxy
  7. GRB 000926 Chandra Observation
  8. Public availability of BeppoSAX data of GRB000926
  9. GRB000926 - Optical observations
  10. GRB000926 - Optical observations
  11. GRB000911: VLT infrared observation
  12. GRB000911: optical VLT observations
  13. GRB000926 K'-band Observation
  14. J and K band observations of GRB 000926
  15. IPN triangulation of GRB000911
  16. False GRB alarm from RXTE/ASM on 8 Sept 2000
  17. GRB000830: Optical observations
  18. GRB000830, TNG B-band observations
  19. IPN localization of GRB000820
  20. GRB000812, TNG R-band observations
  21. GRB000730, Gamma Ray Observations
  22. IPN localization of GRB000812
  23. IPN localization of GRB000811
  24. GRB000801, Gamma Ray Observations
  25. IPN localization of GRB000801
  26. IPN localization of GRB000801
  27. IPN localization of GRB000730B
  28. IPN localization of GRB000730B
  29. IPN localization of GRB000730
  30. GRB 990510: Possible detection of a host galaxy
  31. GRB 990510 Host Galaxy Discovery
  32. IPN localization of GRB000727
  33. GRB 990712: Late time HST/STIS Observations
  34. GRB 991216, HST/STIS observations
  35. GRB 000630: Detection of the Optical Afterglow
  36. GRB000630, Optical Observations
  37. GRB000630, optical observations
  38. GRB000418, HST/STIS Observations
  39. GRB990123: Late-time HST/STIS observations of the host
  40. GRB 990506, HST/STIS Observations of the Host Galaxy
  41. GRB000623
  42. GRB 000620: J-band observations
  43. GRB000620, optical observations
  44. GRB000607, optical observations
  45. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  46. GRB000616 [IPN Position]
  47. GRB 000615: NIR observations
  48. GRB980425, HST/STIS observations of the host galaxy
  49. The Hosts of GRB 980703 and GRB 971214
  50. GRB 000301C: Further Late-Time HST/STIS observations
  51. GRB000528: follow-up X-ray measurements and update of IPN annulus
  52. GRB000607, Radio Observations
  53. GRB000607, A SHORT, HARD BURST
  54. IPN localization and time history of GRB000528
  55. New IPN localization of GRB000529
  56. IPN localization of GRB000529
  57. GRB000528: BeppoSAX GRBM observations
  58. Possible GRB-related phenomenon
  59. RXTE/ASM and IPN localization of GRB 000508B
  60. GRB 000424 Optical Observations
  61. IPN localization of GRB000429
  62. GRB 000418, optical observation
  63. GRB000424 Optical Observations
  64. GRB000424, optical observations
  65. GRB 000424, Optical Observations
  66. Correction to IPN error box for GRB000419
  67. GRB000416 Optical Observations
  68. GRB000416 BRJK observations
  69. GRB000301c results
  70. GRB000408, lotis optical observations
  71. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  72. GRB000408 [IPN Position]
  73. GRB000301C - R magnitude lower limit
  74. GRB 000313 - optical transient in the BATSE error box
  75. GRB 000301C: Optical Spectrum and Redshift
  76. GRB 000301C: Optical Spectrum and Redshift
  77. GRB 000301C: HST/STIS CCD Imaging of the field
  78. GRB 000301C, Optical Observation
  79. GRB 000301c: K' observations
  80. GRB 000301C: K' Observations
  81. GRB000301C - Host galaxy not detected in R (?)
  82. GRB000301C, near-infrared observations (JHK' imaging)
  83. GRB 000301c near-IR observations
  84. GRB 000301C, Optical Color
  85. GRB000301C 250 GHz detection
  86. GRB000301C, optical observations
  87. GRB000301C
  88. GRB000301C: RXTE/ASM and IPN localizations
  89. GRB000301A [IPN Position]
  90. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  91. GRB000210 X-ray afterglow
  92. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  93. GRB 000210: BATSE Observations
  94. Optical candidate for GRB000210
  95. SAX_WFC_GRB_NOTICE
  96. SAX_WFC_GRB_NOTICE
  97. GRB000201 Optical Observations
  98. BATSE+IPN location of GRB000131
  99. IPN localization of GRB000131
  100. GRB 000126, optical observations

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