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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"

37512 results found.

  1. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  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. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  9. GRB000408 [IPN Position]
  10. GRB000326 Optical Observations
  11. GRB000301C - Addendum to GCN 623
  12. GRB000301C - R magnitude lower limit
  13. GRB 000323, optical observations
  14. GRB 000326: Optical Observations
  15. GRB000326, Radio observations
  16. GRB000326 [IPN Position]
  17. GRB 000307 optical observations
  18. GRB000323 [IPN Position]
  19. GRB000315 [IPN Positions]
  20. GRB 000313 - optical transient in the BATSE error box
  21. GRB000301C - B and R photometry
  22. GRB000301C - R photometry
  23. GRB 000307, Optical Observations
  24. GRB 000307, BVRI Field Photometry
  25. GRB 000301C: Optical Spectrum and Redshift
  26. GRB 000301C: Optical Spectrum and Redshift
  27. GRB 000301C: A Precise Redshift Determination
  28. GRB 000301C, Optical Observation
  29. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  30. GRB 000301C: HST/STIS CCD Imaging of the field
  31. IPN error box for GRB000307
  32. GRB 000301c: K' observations
  33. GRB000301C, optical R-band observations
  34. GRB000301c - R photometry and nearby faint source confirmation
  35. GRB 000301C, Optical Observation
  36. GRB 000301c: K' observations
  37. GRB 000301C Optical Observations
  38. GRB 000301C: K' Observations
  39. GRB000301C - Host galaxy not detected in R (?)
  40. GRB000301C optical observations
  41. GRB 000301c near-IR observations
  42. GRB 000301C, Optical Color
  43. GRB000301C, Optical Spectroscopy
  44. GRB 000301C, UBVRI field photometry
  45. GRB 000301C, Optical Observation
  46. GRB000301C 250 GHz detection
  47. GRB 000301C R-band observation
  48. GRB 000301C, Optical Observation
  49. GRB000301C, near-infrared observations (JHK' photometry)
  50. GRB 000301C: OT confirmed
  51. GRB000301c optical observations
  52. GRB 000301A, Radio Observations
  53. GRB000301C, optical observations
  54. GRB000301c, near-infrared observations
  55. GRB000301C
  56. GRB 000301C : Optical Candidate
  57. GRB000301C: RXTE/ASM and IPN localizations
  58. GRB000226 [IPN Position]
  59. HST Observations of GRB 990712
  60. GRB 000214 near-IR observations
  61. GRB 000115 Optical observations
  62. GRB 000214, Radio Observations
  63. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  64. GRB 000115, BVRI field photometry
  65. IPN annulus for GRB000214
  66. BATSE GRB trigger criterion changed
  67. GRB000210 X-ray afterglow
  68. GRB000214: X-ray afterglow candidate
  69. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  70. GRB 000210: BATSE Observations
  71. Optical observations of the Chandra X-ray source for GRB000210
  72. Chandra Observations of GRB000210 X-ray Afterglow
  73. IPN triangulation of GRB000210
  74. GRB 000201: TAROT optical observations
  75. GRB 000131 Optical Observations
  76. GRB000126 Optical Observations
  77. BATSE GRB trigger criteria changed
  78. GRB 991208, radio observations
  79. BATSE+IPN location of GRB000131
  80. IPN localization of GRB000131
  81. GRB 000126, optical observations
  82. GRB000126, optical observations
  83. BATSE location of GRB000126
  84. IPN localization of GRB000126
  85. GRB 000115 Optical observations
  86. BATSE Observations of GRB000115
  87. Second RXTE Observation of GRB 000115
  88. GRB991216, UBVRIJHK field photometry
  89. Single IPN error box for GRB991229
  90. GRB 991216 VLBA Observations
  91. BEPPOSAX GRBM Localization of GRB991226
  92. IPN error boxes for GRB991229
  93. GRB 991216: J band spectrophotometry
  94. GRB 991216: Detection of the Host and/or Absorber Galaxy
  95. IPN localization of GRB991226
  96. Single IPN error box for GRB991221
  97. IPN error boxes for GRB991221
  98. GRB 991216 RXTE ASM Observations
  99. IPN error box for GRB991216
  100. GRB 991216: Updated BATSE parameters

Advanced

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