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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"

45428 results found.

  1. 1SAXJ1715.0-7134 refined position
  2. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  3. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  4. Budget cuts in BeppoSAX operations: impact on GRB observations
  5. GRB 000408, optical observations
  6. Refined IPN error box for GRB000408
  7. GRB 991208, UBVRI field photometry
  8. GRB000301c results
  9. GRB000408: Optical CCD Observations from MIRO
  10. GRB000408, lotis optical observations
  11. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  12. GRB000408 [IPN Position]
  13. GRB000326 Optical Observations
  14. GRB000301C - Addendum to GCN 623
  15. GRB000301C - R magnitude lower limit
  16. GRB000326, Further VLA observations
  17. GRB 000323, optical observations
  18. GRB 000326: Optical Observations
  19. GRB000326, Radio observations
  20. GRB000326 [IPN Position]
  21. GRB 000307 optical observations
  22. GRB000323 [IPN Position]
  23. Single error box for GRB000315
  24. GRB000315 [IPN Positions]
  25. GRB000313, Radio observations
  26. GRB 000313 - optical transient in the BATSE error box
  27. GRB000301C - B and R photometry
  28. GRB000301C - R photometry
  29. GRB 000307, Optical Observations
  30. GRB 000307, BVRI Field Photometry
  31. GRB 000301C: Optical Spectrum and Redshift
  32. GRB 000301C: Optical Spectrum and Redshift
  33. GRB 000301C: A Precise Redshift Determination
  34. GRB 000301C, Optical Observation
  35. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  36. GRB 000301C: HST/STIS CCD Imaging of the field
  37. IPN error box for GRB000307
  38. GRB 000301c: K' observations
  39. GRB000301C, optical R-band observations
  40. GRB000301c - R photometry and nearby faint source confirmation
  41. GRB 000301C, Optical Observation
  42. GRB 000301c: K' observations
  43. GRB 000301C Optical Observations
  44. GRB 000301C: K' Observations
  45. GRB000301C OT candidate optical observations
  46. GRB000301C - Host galaxy not detected in R (?)
  47. Optical observations of GRB000301c
  48. GRB000301C, Radio observations
  49. GRB000301C, Radio observations
  50. GRB000301C optical observations
  51. GRB000301C, near-infrared observations (JHK' imaging)
  52. GRB 000301c near-IR observations
  53. GRB 000301C, Optical Color
  54. GRB000301C, Optical Spectroscopy
  55. GRB 000301C, UBVRI field photometry
  56. GRB 000301C, Optical Observation
  57. GRB000301C, optical observations
  58. GRB000301C 250 GHz detection
  59. GRB 000301C R-band observation
  60. GRB 000301C, Optical Observation
  61. GRB000301C, near-infrared observations (JHK' photometry)
  62. GRB 000301C: OT confirmed
  63. GRB000301c optical observations
  64. GRB 000301A, Radio Observations
  65. GRB000301C, optical observations
  66. GRB000301c, near-infrared observations
  67. GRB000301C
  68. GRB 000301C : Optical Candidate
  69. Radio observations of the error box of GRB000301A
  70. GRB000301C: RXTE/ASM and IPN localizations
  71. GRB000226 [IPN Position]
  72. HST Observations of GRB 990712
  73. GRB 000214 near-IR observations
  74. GRB 000115 Optical observations
  75. GRB 000214, Radio Observations
  76. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  77. GRB000210, Radio Observations
  78. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  79. GRB 000115, BVRI field photometry
  80. GRB000214: BeppoSAX GRBM and WFC Detection
  81. IPN annulus for GRB000214
  82. Optical observations of GRB000210
  83. GRB000210 X-ray afterglow
  84. GRB000214: X-ray afterglow candidate
  85. GRB000214 refined BeppoSAX-WFC position
  86. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  87. GRB 000210: BATSE Observations
  88. Correction to Chandra Position of GRB000210 afterglow
  89. Optical observations of the Chandra X-ray source for GRB000210
  90. GRB000210, Radio Observations
  91. Optical candidate for GRB000210
  92. Chandra Observations of GRB000210 X-ray Afterglow
  93. IPN triangulation of GRB000210
  94. GRB000210: possible afterglow detection with BeppoSAX NFI
  95. GRB000201, Radio Observations
  96. GRB000210: BeppoSAX GRBM and WFC Detection
  97. Optical observations of GRB000131
  98. GRB000201 Optical Observations
  99. GRB 000201: TAROT optical observations
  100. GRB 000131 Optical Observations

Advanced

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