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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"

45450 results found.

  1. GRB 000429, optical observation
  2. GRB 000429, UBVRI field photometry
  3. IPN localization of GRB000429
  4. GRB 000418, UBVRI field photometry
  5. GRB000418, Radio detection
  6. GRB000418, K'-band photometry
  7. GRB 000418, Optical Observation
  8. GRB 000418, optical observation
  9. GRB000424 Optical Observations
  10. GRB 000418, Optical Observation
  11. GRB000424, optical observations
  12. GRB000424, optical observations
  13. GRB 000424, Optical Observations
  14. GRB 000418, Optical Observation
  15. GRB000418, near-infrared observations
  16. BeppoSAX GRB000424
  17. Correction to IPN error box for GRB000419
  18. IPN error box for GRB000418
  19. GRB000419 [IPN Position]
  20. GRB000416 Optical Observations
  21. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  22. GRB000416 BRJK observations
  23. 1SAXJ1715.0-7134 refined position
  24. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  25. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  26. Budget cuts in BeppoSAX operations: impact on GRB observations
  27. GRB 000408, optical observations
  28. Refined IPN error box for GRB000408
  29. GRB 991208, UBVRI field photometry
  30. GRB000301c results
  31. GRB000408: Optical CCD Observations from MIRO
  32. GRB000408, lotis optical observations
  33. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  34. GRB000408 [IPN Position]
  35. GRB000326 Optical Observations
  36. GRB000301C - Addendum to GCN 623
  37. GRB000301C - R magnitude lower limit
  38. GRB000326, Further VLA observations
  39. GRB 000323, optical observations
  40. GRB 000326: Optical Observations
  41. GRB000326, Radio observations
  42. GRB000326 [IPN Position]
  43. GRB 000307 optical observations
  44. GRB000323 [IPN Position]
  45. Single error box for GRB000315
  46. GRB000315 [IPN Positions]
  47. GRB000313, Radio observations
  48. GRB 000313 - optical transient in the BATSE error box
  49. GRB000301C - B and R photometry
  50. GRB000301C - R photometry
  51. GRB 000307, Optical Observations
  52. GRB 000307, BVRI Field Photometry
  53. GRB 000301C: Optical Spectrum and Redshift
  54. GRB 000301C: Optical Spectrum and Redshift
  55. GRB 000301C: A Precise Redshift Determination
  56. GRB 000301C, Optical Observation
  57. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  58. GRB 000301C: HST/STIS CCD Imaging of the field
  59. IPN error box for GRB000307
  60. GRB 000301c: K' observations
  61. GRB000301C, optical R-band observations
  62. GRB000301c - R photometry and nearby faint source confirmation
  63. GRB 000301C, Optical Observation
  64. GRB 000301c: K' observations
  65. GRB 000301C Optical Observations
  66. GRB 000301C: K' Observations
  67. GRB000301C OT candidate optical observations
  68. GRB000301C - Host galaxy not detected in R (?)
  69. Optical observations of GRB000301c
  70. GRB000301C, Radio observations
  71. GRB000301C, Radio observations
  72. GRB000301C optical observations
  73. GRB000301C, near-infrared observations (JHK' imaging)
  74. GRB 000301c near-IR observations
  75. GRB 000301C, Optical Color
  76. GRB000301C, Optical Spectroscopy
  77. GRB 000301C, UBVRI field photometry
  78. GRB 000301C, Optical Observation
  79. GRB000301C, optical observations
  80. GRB000301C 250 GHz detection
  81. GRB 000301C R-band observation
  82. GRB 000301C, Optical Observation
  83. GRB000301C, near-infrared observations (JHK' photometry)
  84. GRB 000301C: OT confirmed
  85. GRB000301c optical observations
  86. GRB 000301A, Radio Observations
  87. GRB000301C, optical observations
  88. GRB000301c, near-infrared observations
  89. GRB000301C
  90. GRB 000301C : Optical Candidate
  91. Radio observations of the error box of GRB000301A
  92. GRB000301C: RXTE/ASM and IPN localizations
  93. GRB000226 [IPN Position]
  94. HST Observations of GRB 990712
  95. GRB 000214 near-IR observations
  96. GRB 000115 Optical observations
  97. GRB 000214, Radio Observations
  98. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  99. GRB000210, Radio Observations
  100. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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