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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

37738 results found.

  1. Swift-BAT trigger 149118 is very likely not a GRB
  2. Retraction of Swift Trigger 149131 (GRB 050805B)
  3. GRB 050805b: OHP optical limits
  4. GRB 050805b: TAROT optical limits
  5. GRB050805b: MASTER optical observations
  6. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  7. GRB050805a: MASTER optical candidat
  8. Swift-BAT trigger 149118 is probably not a GRB
  9. GRB 050803: RTT150 optical observations
  10. GRB050803: CrAO optical observations, possible OT candidate
  11. GRB 050803: Keck Observations
  12. GRB 050803: Swift-BAT refined analysis
  13. GRB 050802.422: Fading of the afterglow and detection of the host
  14. GRB050803: MASTER further analys
  15. GRB 050803, optical observations
  16. GRB 050803: Magellan Observations
  17. GRB 050803: early Swift XRT analysis results
  18. GRB 050803: TAROT optical limits
  19. GRB050803: MASTER optical observations
  20. GRB050802: Tentative absorption redshift
  21. GCN GRB observation 050713A
  22. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  23. GRB 050802: Swift/UVOT optical and UV detections
  24. GRB050802: CrAO optical observations
  25. GRB050801: Unchanged decay slope
  26. GRB 050730: OHP optical observations
  27. GRB 050802: early Swift XRT analysis results
  28. GRB 050802: Swift/UVOT observations
  29. GRB 050802 : Lulin Optical follow-up observation
  30. GRB 050802: Swift-BAT refined analysis
  31. GRB050801: Optical photometry and decay index
  32. GRB 050802: XRT position
  33. GRB 050802: Swift Gamma-ray Burst
  34. GRB 050730: Preliminary Analysis of MIKE Spectrum
  35. GCN 050801: early Swift XRT analysis results
  36. GRB 050801: Swift-BAT refined analysis
  37. GRB 050801, SMARTS optical/IR afterglow observations
  38. GRB 050801, afterglow observations
  39. GRB 050730, corrected photometry and break?
  40. GRB 050801: ROTSE-III Early Afterglow Break
  41. GRB050801: Swift-BAT detection of a burst
  42. GRB 050801: ROTSE-III Detection of Possible Counterpart
  43. GRB 050730: XRT refined analysis
  44. Correction to GCN Circ 3476 on GRB050525A
  45. GRB 050730: early TAROT optical observations
  46. GRB 050726: PROMPT Rc Observations
  47. GRB 050730: RTT150 optical observations
  48. GRB 050730, spectra and optical photometry
  49. GRB050730: Refined BAT analysis of the Swift-BAT burst
  50. GRB 050730: Swift XRT afterglow observations
  51. GRB 050730 XMM-Newton observation
  52. GRB 050730: PROMPT VRcIc Observations
  53. GRB050730, afterglow observations
  54. GRB050730: confirmation of redshift
  55. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  56. GRB 050730, SMARTS optical/IR afterglow observations
  57. GRB 050730 : Planned XMM-Newton observation
  58. GRB050730: Liverpool Telescope optical observations
  59. GRB 050730, optical candidate
  60. GRB050730: Swift-BAT detection of a weak burst
  61. GRB 050713A: Swift XRT extended light curve
  62. GRB 050709: PROMPT Rc Observations
  63. GRB050713b: Maidanak optical observations
  64. GRB 050724: Secure Host Redshift from Keck
  65. GRB 050724: WHT optical observations
  66. GRB 050724: Chandra Observations of the X-ray Afterglow
  67. GRB050713: analysis of the XMM-Newton observation
  68. GRB 050724, SMARTS optical/IR afterglow observations
  69. GRB 050726, SMARTS optical/IR observations
  70. Swift-BAT trigger 147918 is not a real GRB
  71. GRB 050727: RTT150 optical observations
  72. GRB050727: KAIT optical limit
  73. GRB050709: Second Epoch Chandra Observation
  74. GRB 050726: PROMPT Rc Observations
  75. GRB050709: Second Epoch Chandra Observation
  76. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  77. GRB 050726: early Swift XRT analysis results
  78. GRB 050724: Optical Variability in Nearby Galaxy
  79. GRB 050724: J-band observations
  80. GRB 050724: GMOS Imaging and Spectroscopy
  81. GRB 050724: SWIFT XRT refined position
  82. GRB 050724: spectroscopy of object in the XRT error circle
  83. GRB 050724: Optical limit
  84. GRB 050724: optical and near-IR observations
  85. GRB 050724: Optical imaging/astrometry
  86. GRB 050724: RTT150 optical observations
  87. GRB 050724: Swift/UVOT Upper Limit
  88. GRB 050724: early Swift XRT analysis results
  89. GRB 050724 : Lulin early R-band monitoring observations
  90. GRB050724: Refined analysis of the Swift-BAT possible short burst
  91. GRB 050724: possible host galaxy in DSS
  92. Swift-BAT trigger 147325 is not due to a real GRB
  93. GRB050723: XRT distributed coordinates are not related to the burst
  94. GRB 050721: early afterglow light curve
  95. GRB 050721A: Swift-BAT refined analysis
  96. Correction to GCN Circ 3474 on GRB050525A
  97. GRB 050721A: Early Swift XRT analysis results
  98. GRB050721A: optical decay
  99. GRB 050721: optical afterglow confirmed
  100. Swift BAT Trigger 146986 is SWIFT J1753.5-0127

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