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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"

37256 results found.

  1. GRB050730, optical observations
  2. GRB050803, optical observations
  3. Swift-BAT trigger 149118 is very likely not a GRB
  4. Retraction of Swift Trigger 149131 (GRB 050805B)
  5. GRB 050805b: OHP optical limits
  6. GRB 050805b: TAROT optical limits
  7. GRB050805b: MASTER optical observations
  8. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  9. GRB050805a: MASTER optical candidat
  10. Swift-BAT trigger 149118 is probably not a GRB
  11. GRB 050803: RTT150 optical observations
  12. GRB050803: CrAO optical observations, possible OT candidate
  13. GRB 050803: Keck Observations
  14. GRB 050803: Swift-BAT refined analysis
  15. GRB 050802.422: Fading of the afterglow and detection of the host
  16. GRB050803: MASTER further analys
  17. GRB 050803, optical observations
  18. GRB 050803: Magellan Observations
  19. GRB 050803: early Swift XRT analysis results
  20. GRB 050803: TAROT optical limits
  21. GRB050803: MASTER optical observations
  22. GRB050802: Tentative absorption redshift
  23. GCN GRB observation 050713A
  24. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  25. GRB 050802: Swift/UVOT optical and UV detections
  26. GRB050802: CrAO optical observations
  27. GRB050801: Unchanged decay slope
  28. GRB 050730: OHP optical observations
  29. GRB 050802: early Swift XRT analysis results
  30. GRB 050802: Swift/UVOT observations
  31. GRB 050802 : Lulin Optical follow-up observation
  32. GRB 050802: Swift-BAT refined analysis
  33. GRB050801: Optical photometry and decay index
  34. GRB 050802: XRT position
  35. GRB 050802: Swift Gamma-ray Burst
  36. GRB 050730: Preliminary Analysis of MIKE Spectrum
  37. GCN 050801: early Swift XRT analysis results
  38. GRB 050801: Swift-BAT refined analysis
  39. GRB 050801, SMARTS optical/IR afterglow observations
  40. GRB 050801, afterglow observations
  41. GRB 050730, corrected photometry and break?
  42. GRB 050801: ROTSE-III Early Afterglow Break
  43. GRB050801: Swift-BAT detection of a burst
  44. GRB 050801: ROTSE-III Detection of Possible Counterpart
  45. GRB 050730: XRT refined analysis
  46. Correction to GCN Circ 3476 on GRB050525A
  47. GRB 050730: early TAROT optical observations
  48. GRB 050726: PROMPT Rc Observations
  49. GRB 050730: RTT150 optical observations
  50. GRB 050730, spectra and optical photometry
  51. GRB050730: Refined BAT analysis of the Swift-BAT burst
  52. GRB 050730: Swift XRT afterglow observations
  53. GRB 050730 XMM-Newton observation
  54. GRB 050730: PROMPT VRcIc Observations
  55. GRB050730, afterglow observations
  56. GRB050730: confirmation of redshift
  57. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  58. GRB 050730, SMARTS optical/IR afterglow observations
  59. GRB 050730 : Planned XMM-Newton observation
  60. GRB050730: Liverpool Telescope optical observations
  61. GRB 050730, optical candidate
  62. GRB050730: Swift-BAT detection of a weak burst
  63. GRB 050713A: Swift XRT extended light curve
  64. GRB 050709: PROMPT Rc Observations
  65. GRB050713b: Maidanak optical observations
  66. GRB 050724: Secure Host Redshift from Keck
  67. GRB 050724: WHT optical observations
  68. GRB 050724: Chandra Observations of the X-ray Afterglow
  69. GRB050713: analysis of the XMM-Newton observation
  70. GRB 050724, SMARTS optical/IR afterglow observations
  71. GRB 050726, SMARTS optical/IR observations
  72. Swift-BAT trigger 147918 is not a real GRB
  73. GRB 050727: RTT150 optical observations
  74. GRB050724: VLT observations of the variable source
  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. GRB050726: Swift-BAT detection of a weak burst
  82. GRB 050724: Optical Variability in Nearby Galaxy
  83. GRB 050724: J-band observations
  84. GRB 050724: GMOS Imaging and Spectroscopy
  85. GRB 050724: SWIFT XRT refined position
  86. GRB 050724: spectroscopy of object in the XRT error circle
  87. GRB 050724: Optical limit
  88. GRB 050724: optical and near-IR observations
  89. GRB 050724: Optical imaging/astrometry
  90. GRB 050724: RTT150 optical observations
  91. GRB 050724: Swift/UVOT Upper Limit
  92. GRB 050724: early Swift XRT analysis results
  93. GRB 050724 : Lulin early R-band monitoring observations
  94. GRB050724: Refined analysis of the Swift-BAT possible short burst
  95. GRB 050724: possible host galaxy in DSS
  96. Swift-BAT trigger 147325 is not due to a real GRB
  97. GRB050723: XRT distributed coordinates are not related to the burst
  98. GRB 050721: early afterglow light curve
  99. GRB 050721A: Swift-BAT refined analysis
  100. Correction to GCN Circ 3474 on GRB050525A

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