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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19138 results found.

  1. GRB 000418, Optical Observation
  2. GRB000424 Optical Observations
  3. GRB000424, optical observations
  4. GRB000424, optical observations
  5. GRB 000424, Optical Observations
  6. GRB 000418, Optical Observation
  7. GRB000418, near-infrared observations
  8. GRB000416 Optical Observations
  9. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  10. GRB000416 BRJK observations
  11. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  12. Budget cuts in BeppoSAX operations: impact on GRB observations
  13. GRB 000408, optical observations
  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. GRB000326 Optical Observations
  18. GRB000301C - Addendum to GCN 623
  19. GRB000301C - R magnitude lower limit
  20. GRB000326, Further VLA observations
  21. GRB 000323, optical observations
  22. GRB 000326: Optical Observations
  23. GRB000326, Radio observations
  24. GRB 000307 optical observations
  25. GRB000313, Radio observations
  26. GRB 000313 - optical transient in the BATSE error box
  27. GRB000301C - B and R photometry
  28. GRB 000307, Optical Observations
  29. GRB 000301C: A Precise Redshift Determination
  30. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  31. GRB 000301C: HST/STIS CCD Imaging of the field
  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 OT candidate optical observations
  40. GRB000301C - Host galaxy not detected in R (?)
  41. Optical observations of GRB000301c
  42. GRB000301C, Radio observations
  43. GRB000301C, Radio observations
  44. GRB000301C optical observations
  45. GRB000301C, near-infrared observations (JHK' imaging)
  46. GRB 000301c near-IR observations
  47. GRB000301C, optical observations
  48. GRB000301C, near-infrared observations (JHK' photometry)
  49. GRB000301c optical observations
  50. GRB 000301A, Radio Observations
  51. GRB000301C, optical observations
  52. GRB000301c, near-infrared observations
  53. Radio observations of the error box of GRB000301A
  54. HST Observations of GRB 990712
  55. GRB 000214 near-IR observations
  56. GRB 000115 Optical observations
  57. GRB 000214, Radio Observations
  58. GRB000210, Radio Observations
  59. Optical observations of GRB000210
  60. GRB 000210: BATSE Observations
  61. Optical observations of the Chandra X-ray source for GRB000210
  62. GRB000210, Radio Observations
  63. Optical candidate for GRB000210
  64. Chandra Observations of GRB000210 X-ray Afterglow
  65. GRB000201, Radio Observations
  66. Optical observations of GRB000131
  67. GRB000201 Optical Observations
  68. GRB 000201: TAROT optical observations
  69. GRB 000131 Optical Observations
  70. GRB000126 Optical Observations
  71. GRB 991208, radio observations
  72. GRB 000126, optical observations
  73. GRB000126, optical observations
  74. GRB 000115 Optical observations
  75. BATSE Observations of GRB000115
  76. GRB991216, UBVRIJHK field photometry
  77. GRB991216 late optical observation
  78. GRB 991216 VLBA Observations
  79. IPN error boxes for GRB991229
  80. GRB 991216: J band spectrophotometry
  81. GRB 991216: Detection of the Host and/or Absorber Galaxy
  82. GRB 991216 RXTE ASM Observations
  83. Lowell/Perkins observation of GRB 991216
  84. GRB 991217 (SAX J2303.2+0015) Optical observations
  85. GRB991217/SAX J2303.2+0015, optical observations
  86. GRB 991216, optical observations
  87. GRB 991216 Optical Observations
  88. GRB 991216 Optical spectroscopy/imaging
  89. GRB991216 Optical and IR observations
  90. K observations of GRB991216
  91. SAX J2303.2+0015 Optical observations
  92. IR observations of GRB991216
  93. GRB991216 radio observations
  94. GRB 991217 (SAX J2303.2+0015) Optical observations
  95. GRB991216 radio observations
  96. GRB991216, optical observations
  97. GRB991216 Optical and infrared observations of Beethoven Burst
  98. GRB 991216 Radio Observations
  99. GRB 991208 Keck Spectroscopy
  100. GRB 991208 Infrared Detection

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