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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"

42182 results found.

  1. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  2. GRB 000408, optical observations
  3. GRB 991208, UBVRI field photometry
  4. GRB000301c results
  5. GRB000408: Optical CCD Observations from MIRO
  6. GRB000408, lotis optical observations
  7. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  8. GRB000408 [IPN Position]
  9. GRB000326 Optical Observations
  10. GRB000301C - Addendum to GCN 623
  11. GRB000301C - R magnitude lower limit
  12. GRB 000323, optical observations
  13. GRB 000326: Optical Observations
  14. GRB000326, Radio observations
  15. GRB000326 [IPN Position]
  16. GRB 000307 optical observations
  17. GRB000313, Radio observations
  18. GRB 000313 - optical transient in the BATSE error box
  19. GRB000301C - B and R photometry
  20. GRB000301C - R photometry
  21. GRB 000307, Optical Observations
  22. GRB 000307, BVRI Field Photometry
  23. GRB 000301C: Optical Spectrum and Redshift
  24. GRB 000301C: Optical Spectrum and Redshift
  25. GRB 000301C: A Precise Redshift Determination
  26. GRB 000301C, Optical Observation
  27. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  28. GRB 000301C: HST/STIS CCD Imaging of the field
  29. IPN error box for GRB000307
  30. GRB 000301c: K' observations
  31. GRB000301C, optical R-band observations
  32. GRB000301c - R photometry and nearby faint source confirmation
  33. GRB 000301C, Optical Observation
  34. GRB 000301c: K' observations
  35. GRB 000301C Optical Observations
  36. GRB 000301C: K' Observations
  37. GRB000301C OT candidate optical observations
  38. GRB000301C - Host galaxy not detected in R (?)
  39. Optical observations of GRB000301c
  40. GRB000301C, Radio observations
  41. GRB000301C, Radio observations
  42. GRB000301C optical observations
  43. GRB000301C, near-infrared observations (JHK' imaging)
  44. GRB 000301c near-IR observations
  45. GRB 000301C, Optical Color
  46. GRB000301C, Optical Spectroscopy
  47. GRB 000301C, UBVRI field photometry
  48. GRB 000301C, Optical Observation
  49. GRB000301C, optical observations
  50. GRB000301C 250 GHz detection
  51. GRB 000301C R-band observation
  52. GRB 000301C, Optical Observation
  53. GRB000301C, near-infrared observations (JHK' photometry)
  54. GRB 000301C: OT confirmed
  55. GRB000301c optical observations
  56. GRB 000301A, Radio Observations
  57. GRB000301C, optical observations
  58. GRB000301c, near-infrared observations
  59. GRB000301C
  60. GRB 000301C : Optical Candidate
  61. Radio observations of the error box of GRB000301A
  62. GRB000301C: RXTE/ASM and IPN localizations
  63. GRB000301A [IPN Position]
  64. HST Observations of GRB 990712
  65. GRB 000214 near-IR observations
  66. GRB 000115 Optical observations
  67. GRB 000214, Radio Observations
  68. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  69. GRB000210, Radio Observations
  70. GRB 000115, BVRI field photometry
  71. GRB000214: BeppoSAX GRBM and WFC Detection
  72. IPN annulus for GRB000214
  73. Optical observations of GRB000210
  74. GRB000210 X-ray afterglow
  75. GRB000214: X-ray afterglow candidate
  76. GRB000214 refined BeppoSAX-WFC position
  77. GRB 000210: BATSE Observations
  78. Correction to Chandra Position of GRB000210 afterglow
  79. Optical observations of the Chandra X-ray source for GRB000210
  80. Optical candidate for GRB000210
  81. Chandra Observations of GRB000210 X-ray Afterglow
  82. IPN triangulation of GRB000210
  83. GRB000210: possible afterglow detection with BeppoSAX NFI
  84. GRB000201, Radio Observations
  85. GRB000210: BeppoSAX GRBM and WFC Detection
  86. Optical observations of GRB000131
  87. GRB000201 Optical Observations
  88. GRB 000201: TAROT optical observations
  89. GRB 000131 Optical Observations
  90. GRB000126 Optical Observations
  91. GRB 991208, radio observations
  92. BATSE+IPN location of GRB000131
  93. GRB 000126, optical observations
  94. GRB000126, optical observations
  95. BATSE location of GRB000126
  96. GRB 000115 Optical observations
  97. BATSE Observations of GRB000115
  98. IPN annulus for GRB000115
  99. Second RXTE Observation of GRB 000115
  100. GRB991216, UBVRIJHK field photometry

Advanced

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