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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"

41191 results found.

  1. GRB000418, near-infrared observations
  2. BeppoSAX GRB000424
  3. Correction to IPN error box for GRB000419
  4. IPN error box for GRB000418
  5. GRB000416 Optical Observations
  6. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  7. GRB000416 BRJK observations
  8. 1SAXJ1715.0-7134 refined position
  9. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  10. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  11. GRB 000408, optical observations
  12. GRB 991208, UBVRI field photometry
  13. GRB000301c results
  14. GRB000408: Optical CCD Observations from MIRO
  15. GRB000408, lotis optical observations
  16. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  17. GRB000408 [IPN Position]
  18. GRB000326 Optical Observations
  19. GRB000301C - Addendum to GCN 623
  20. GRB000301C - R magnitude lower limit
  21. GRB 000323, optical observations
  22. GRB 000326: Optical Observations
  23. GRB000326, Radio observations
  24. GRB000326 [IPN Position]
  25. GRB 000307 optical observations
  26. GRB000313, Radio observations
  27. GRB 000313 - optical transient in the BATSE error box
  28. GRB000301C - B and R photometry
  29. GRB000301C - R photometry
  30. GRB 000307, Optical Observations
  31. GRB 000307, BVRI Field Photometry
  32. GRB 000301C: Optical Spectrum and Redshift
  33. GRB 000301C: Optical Spectrum and Redshift
  34. GRB 000301C: A Precise Redshift Determination
  35. GRB 000301C, Optical Observation
  36. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  37. GRB 000301C: HST/STIS CCD Imaging of the field
  38. IPN error box for GRB000307
  39. GRB 000301c: K' observations
  40. GRB000301C, optical R-band observations
  41. GRB000301c - R photometry and nearby faint source confirmation
  42. GRB 000301C, Optical Observation
  43. GRB 000301c: K' observations
  44. GRB 000301C Optical Observations
  45. GRB 000301C: K' Observations
  46. GRB000301C OT candidate optical observations
  47. GRB000301C - Host galaxy not detected in R (?)
  48. Optical observations of GRB000301c
  49. GRB000301C, Radio observations
  50. GRB000301C, Radio observations
  51. GRB000301C optical observations
  52. GRB000301C, near-infrared observations (JHK' imaging)
  53. GRB 000301c near-IR observations
  54. GRB 000301C, Optical Color
  55. GRB000301C, Optical Spectroscopy
  56. GRB 000301C, UBVRI field photometry
  57. GRB 000301C, Optical Observation
  58. GRB000301C, optical observations
  59. GRB000301C 250 GHz detection
  60. GRB 000301C R-band observation
  61. GRB 000301C, Optical Observation
  62. GRB000301C, near-infrared observations (JHK' photometry)
  63. GRB 000301C: OT confirmed
  64. GRB000301c optical observations
  65. GRB 000301A, Radio Observations
  66. GRB000301C, optical observations
  67. GRB000301c, near-infrared observations
  68. GRB000301C
  69. GRB 000301C : Optical Candidate
  70. Radio observations of the error box of GRB000301A
  71. GRB000301C: RXTE/ASM and IPN localizations
  72. GRB000301A [IPN Position]
  73. HST Observations of GRB 990712
  74. GRB 000214 near-IR observations
  75. GRB 000115 Optical observations
  76. GRB 000214, Radio Observations
  77. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  78. GRB000210, Radio Observations
  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. GRB 000210: BATSE Observations
  87. Correction to Chandra Position of GRB000210 afterglow
  88. Optical observations of the Chandra X-ray source for GRB000210
  89. Optical candidate for GRB000210
  90. Chandra Observations of GRB000210 X-ray Afterglow
  91. IPN triangulation of GRB000210
  92. GRB000210: possible afterglow detection with BeppoSAX NFI
  93. GRB000201, Radio Observations
  94. GRB000210: BeppoSAX GRBM and WFC Detection
  95. Optical observations of GRB000131
  96. GRB000201 Optical Observations
  97. GRB 000201: TAROT optical observations
  98. GRB 000131 Optical Observations
  99. GRB000126 Optical Observations
  100. GRB 991208, radio observations

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