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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"

42902 results found.

  1. GRB 060427, optical observation
  2. GRB 060427: Swift detection of a burst
  3. GRB 060425: IPN localization and KW spectrum of a short, hard burst
  4. An interactive program for GRB pseudo-redshift computations
  5. GRB060424: optical afterglow detection
  6. GRB060418: Further Analysis of MIKE Spectroscopy
  7. GRB 060424: Refined analysis of the Swift-BAT burst
  8. GRB 060424: Swift detection of a burst
  9. GRB 060421: TTT Observations
  10. OT 060420: Likely Not a New Cosmic Transient
  11. No OT 060420 in MASCOT images
  12. Swift-BAT detection of Mrk 421
  13. OT 060420: CONCAM detection of a candidate new magnitude 5 optical
  14. GRB060421: Swift/UVOT observations
  15. GRB 060421: Swift-BAT Refined Analysis
  16. GRB 060421: Swift-XRT refined analysis
  17. GRB 060418: prediction of t_break
  18. GRB060418: optical observations
  19. Konus-Wind observation of GRB 060418
  20. GRB(?)060421 : XRT position
  21. GRB(?) 060421: Swift detection of a burst
  22. GRB 060418: JHKs PAIRITEL Observations of Afterglow
  23. GRB 060418: Radio Observations
  24. GRB060418, BVRcIc field calibration
  25. GRB060418: Swift/UVOT Observations
  26. GRB060418: Optical Observations
  27. GRB 060418: Refined Analysis of the Swift-BAT burst
  28. VLT/UVES observations of GRB060418
  29. GRB060418: Swift XRT Team Refined Analysis
  30. GRB 060418: PROMPT Detections
  31. GRB 060418, SMARTS optical/IR afterglow observations
  32. GRB060418: Magellan/MIKE Spectroscopic Redshift
  33. GRB060418 : LT optical afterglow observation
  34. GRB 060418: REM candidate afterglow
  35. GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
  36. SGR 1900+14: Refined analysis of the Swift-BAT outburst
  37. GRB060413: Swift/UVOT upper limits
  38. GRB 060413: REM NIR Observations
  39. SGR 1900+14: Swift detection of an outburst
  40. GRB 060413: Refined analysis of the Swift-BAT burst
  41. GRB 060413: Watcher UBVR observations
  42. GRB 060413: XRT refined analysis
  43. GRB 060413: No Optical Afterglow in Swift/UVOT TDRSS Data
  44. GRB 060413: Swift detection of a burst
  45. GRB060403: optical observations
  46. GRB 060403: MITSuME optical observation
  47. GRB060403: Optical Limit
  48. GRB060403: XRT refined analysis
  49. GRB 060403: Swift/UVOT upper limits
  50. HETE Triggers H4043 and H4044 Not Due to New Cosmic Source
  51. SGR 1900+14: BAT observations
  52. GRB 060403: Refined analysis of the Swift-BAT burst
  53. GRB060403: Swift XRT refined position
  54. Konus-Wind observation of the recent SGR 1900+14 activity. Will
  55. GRB 060403: Swift detection of a burst
  56. HETE trigger H4044: RTT150 optical observations
  57. GRB060331: Swift/UVOT upper limits
  58. H4044, a Repeat Outburst From The Source of H4043 (="GRB060331")
  59. Swift XRT observations of the HETE transient H4043
  60. Correction to Circular 4938, =H4043, an unusual high energy transient observed by HETE
  61. H4043, an unusual high-energy transient observed by HETE
  62. GRB 060322: LNA optical limit
  63. SGR 1900+14: bright burst detected by Konus-Wind on March 28
  64. SGR 1900+14: Swift-BAT detection of a cluster of outbursts
  65. SGR 1900+14: Swift-BAT detection of a bright outburst
  66. GRB 060218SN 2006aj: optical observations at Rozhen Observatory
  67. GRB 060323 : WIDGET simultaneous optical observations
  68. GRB 060323: Early optical observation at Xinglong
  69. GRB060218, optical observations
  70. GRB 060322: Confirmation of Swift XRT afterglow
  71. GRB 060211A: optical observation
  72. GRB060211B: optical observation
  73. SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
  74. SGR 1900+14: Swift detection of renewed activity
  75. GRB 060322: IAC80 optical observations
  76. GRB 060322: Swift XRT afterglow candidate
  77. GRB060323: P60 Observations
  78. GRB 060323: Swift/UVOT Observations
  79. GRB 060323: optical afterglow confirmed
  80. GRB060323: NOT observations
  81. GRB 060323: Optical Observations
  82. GRB 060323: Tautenburg OT candidate retraction
  83. GRB 060323: Refined analysis of the Swift-BAT burst
  84. GRB 060323: optical observations at TNG
  85. GRB 060323: Swift XRT refined analysis
  86. GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
  87. GRB 060323: Swift/XRT position
  88. GRB 060322: Refined analysis of the Swift-BAT burst
  89. GRB060323, optical observation
  90. GRB060323 - SDSS Pre-Burst Observations
  91. GRB 060323: Swift detection of a burst with a possible optical afterglow
  92. GRB 060322: Swift-BAT detection of a 200-sec burst
  93. GRB060219: optical observation
  94. GRB060206: optical observation
  95. GRB060218/SN2006aj: optical observations
  96. GRB 060218/SN 2006aj, LNA optical observation
  97. GRB060218: Refined photometric calibration of comparison stars
  98. GRB 060319: WHT K-band candidate afterglow
  99. GRB 060319: IAC-80 optical observations
  100. GRB060319: Swift XRT refined analysis

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