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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"

21321 results found.

  1. GRB000301C - Addendum to GCN 623
  2. GRB000301C - R magnitude lower limit
  3. GRB000326, Further VLA observations
  4. GRB 000323, optical observations
  5. GRB 000326: Optical Observations
  6. GRB000326, Radio observations
  7. GRB 000307 optical observations
  8. GRB000313, Radio observations
  9. GRB 000313 - optical transient in the BATSE error box
  10. GRB000301C - B and R photometry
  11. GRB 000307, Optical Observations
  12. GRB 000301C: A Precise Redshift Determination
  13. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  14. GRB 000301C: HST/STIS CCD Imaging of the field
  15. GRB 000301c: K' observations
  16. GRB000301C, optical R-band observations
  17. GRB000301c - R photometry and nearby faint source confirmation
  18. GRB 000301C, Optical Observation
  19. GRB 000301c: K' observations
  20. GRB 000301C Optical Observations
  21. GRB 000301C: K' Observations
  22. GRB000301C OT candidate optical observations
  23. GRB000301C - Host galaxy not detected in R (?)
  24. Optical observations of GRB000301c
  25. GRB000301C, Radio observations
  26. GRB000301C, Radio observations
  27. GRB000301C optical observations
  28. GRB000301C, near-infrared observations (JHK' imaging)
  29. GRB 000301c near-IR observations
  30. GRB000301C, optical observations
  31. GRB000301C, near-infrared observations (JHK' photometry)
  32. GRB000301c optical observations
  33. GRB 000301A, Radio Observations
  34. GRB000301C, optical observations
  35. GRB000301c, near-infrared observations
  36. Radio observations of the error box of GRB000301A
  37. HST Observations of GRB 990712
  38. GRB 000214 near-IR observations
  39. GRB 000115 Optical observations
  40. GRB 000214, Radio Observations
  41. GRB000210, Radio Observations
  42. Optical observations of GRB000210
  43. GRB 000210: BATSE Observations
  44. Optical observations of the Chandra X-ray source for GRB000210
  45. GRB000210, Radio Observations
  46. Optical candidate for GRB000210
  47. Chandra Observations of GRB000210 X-ray Afterglow
  48. GRB000201, Radio Observations
  49. Optical observations of GRB000131
  50. GRB000201 Optical Observations
  51. GRB 000201: TAROT optical observations
  52. GRB 000131 Optical Observations
  53. GRB000126 Optical Observations
  54. GRB 991208, radio observations
  55. GRB 000126, optical observations
  56. GRB000126, optical observations
  57. GRB 000115 Optical observations
  58. BATSE Observations of GRB000115
  59. GRB991216, UBVRIJHK field photometry
  60. GRB991216 late optical observation
  61. GRB 991216 VLBA Observations
  62. IPN error boxes for GRB991229
  63. GRB 991216: J band spectrophotometry
  64. GRB 991216: Detection of the Host and/or Absorber Galaxy
  65. GRB 991216 RXTE ASM Observations
  66. Lowell/Perkins observation of GRB 991216
  67. GRB 991217 (SAX J2303.2+0015) Optical observations
  68. GRB991217/SAX J2303.2+0015, optical observations
  69. GRB 991216, optical observations
  70. GRB 991216 Optical Observations
  71. GRB 991216 Optical spectroscopy/imaging
  72. GRB991216 Optical and IR observations
  73. K observations of GRB991216
  74. SAX J2303.2+0015 Optical observations
  75. IR observations of GRB991216
  76. GRB991216 radio observations
  77. GRB 991217 (SAX J2303.2+0015) Optical observations
  78. GRB991216 radio observations
  79. GRB991216, optical observations
  80. GRB991216 Optical and infrared observations of Beethoven Burst
  81. GRB 991216 Radio Observations
  82. GRB 991208 Keck Spectroscopy
  83. GRB 991208 Infrared Detection
  84. GRB 991216--Summary of RXTE Observations
  85. GRB 991216 Optical Observations
  86. GRB 991216, optical observations
  87. GRB 991208 SAO-RAS Spectroscopy
  88. GRB 991216, Optical Transient
  89. GRB 991216, Optical Afterglow
  90. GRB991216 ('Beethoven Burst') B, R, and K Observations
  91. GRB991216, infrared observations
  92. GRB991216 Optical Observations
  93. GRB 991208 optical observations
  94. GRB 991208 Keck Spectroscopy
  95. GRB 991216: Extremely bright BATSE burst
  96. R-band Observations of GRB991208 at TNG
  97. GRB991208, optical observations
  98. GRB 991208 Keck Spectroscopy
  99. GRB991208 15-GHz observations
  100. GRB991208, optical observations

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