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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"

38679 results found.

  1. GRB 051221B: Optical Observations with Kuiper 1.54m
  2. GRB 051227: Likely host galaxy underlying afterglow position
  3. GRB 051227: optical observation
  4. GRB051221B: Radio observations
  5. GRB 051221A: VLA Radio Observations
  6. GRB051227: Radio Observations
  7. GRB 051227: Confirmed fading from Gemini observations
  8. GRB051227: further analysis of VLT images
  9. GRB 051227: optical afterglow
  10. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  11. GRB 051227: Gemini observations
  12. GRB 051227: refined analysis of VLT images
  13. GRB 051227: P60 Observations
  14. GRB 051227: MDM Observation
  15. GRB 051227: R-band object in the XRT error circle
  16. GRB 051227: Joint Swift-HETE Spectral Analysis
  17. GRB 051227: XRT refined analysis
  18. GRB 051227: Further analysis of the Swift-BAT burst
  19. GRB 051227: Refined analysis of the Swift-BAT burst
  20. GRB051227: SDSS pre-burst observations
  21. GRB 051227, optical observation
  22. GRB 051227: Swift detection of a burst
  23. IBAS_alert n. 2719 : not a real GRB
  24. Konus-Wind observation of GRB 051221A
  25. GRB 051221A: MDM Optical Observations
  26. GRB051016: analysis of the XMM-Newton observation
  27. GRB 051221A: Detection at 251nm with Swift UVOT
  28. GRB 051221A: Chandra Afterglow Position
  29. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  30. GRB 051221B: ROTSE-III Optical Limits
  31. GRB 051221B: TAROT optical limits
  32. GRB 051221A: WSRT Radio Observations
  33. GRB 051221: Continued fading of optical afterglow
  34. GRB 051221B: Refined analysis of the Swift-BAT burst
  35. Possible GRB 051221B: MDM Optical Detection
  36. GRB 051221A: RAPTOR Fading Counterpart Constraint
  37. Possible GRB 051221B: Swift XRT position
  38. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  39. Swift-BAT detection of a possible burst
  40. GRB 051221: Discovery of fading optical afterglow
  41. GRB 051221: Swift XRT refined analysis
  42. GRB 051221: Swift/UVOT upper limits
  43. GRB 051221: Gemini observations
  44. GRB 051221: XRT position
  45. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  46. GRB 051221: IR Observations at GRB+1hr
  47. GRB 051221: Swift detection of a bright short burst
  48. Refined analysis of the SWIFT J1626.6-5156
  49. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  50. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  51. GRB051211A (=H3979): Refined Analysis
  52. GRB 051211B: optical afterglow
  53. Swift detection of an RS CVn flare star
  54. Swift Trigger 172767 is not a GRB
  55. GRB 051215: near-infrared observations
  56. GRB051215 - SDSS pre-burst observations
  57. GRB 051215: Swift detection of a possible burst
  58. GRB051211B: Probable radio afterglow
  59. GRB051105: optical observations
  60. GRB 051213: Swift-BAT refined analysis
  61. GRB051211B: XRT refined analysis
  62. GRB 051211B, optical observation
  63. GRB 051213: Swift-BAT detection of a burst
  64. GRB051211B, RBO optical observations
  65. GRB 051211A: Swift/UVOT upper limits
  66. GRB 051211B: Swift/UVOT upper limits
  67. GRB 051211A,optical observation
  68. GRB 051211B: Swift XRT confirmation of the afterglow
  69. GRB 051211b: RTT150 optical observations
  70. GRB051211b: P60 Observations
  71. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  72. GRB 051211B: Swift XRT Observations
  73. GRB 051210: Swift/UVOT upper limits
  74. GRB 051211: TAROT optical limits
  75. GRB 051211B: a possible optical detection by TAROT
  76. GRB 051211B: a long GRB detected by INTEGRAL
  77. GRB 051211: Swift XRT upper limit
  78. GRB 051211:IAC80 optical observations
  79. HETE SXC localization of GRB 051211 (=H3979)
  80. GRB 051210: Optical imaging from Las Campanas
  81. GRB 051210: SALT detection limit
  82. GRB 051210: BAT further refined analysis of the short burst
  83. GRB 051210: Swift XRT refined analysis
  84. GRB 051210: Swift-BAT refined analysis of a short burst
  85. GRB051210: Swift UVOT Observation
  86. GRB 051210: Swift detection of a burst
  87. IPN observations of SGR1806-20
  88. Swift XRT positions
  89. An extraordinary long burst on December 3 from SGR1806-20
  90. IBAS Alert 2706 : not a real GRB
  91. Possible resuming of the SGR 1806-20 activity
  92. Swift UVOT Calibration Documentation
  93. GRB051117B: optical observation
  94. GRB051111: optical observaion
  95. Swift-BAT trigger 165579 is not a GRB
  96. GRB 051127: Swift-BAT detection of a possible burst
  97. GRB051117B: Swift XRT refined analysis
  98. GRB051117b: No Swift/UVOT Detection
  99. GRB051111: Rc optical observations: correction
  100. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction

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