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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"

36347 results found.

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

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