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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"

32689 results found.

  1. GRB 050819 Swift-BAT refined analysis
  2. GRB050819: Swift XRT position
  3. Swift-BAT trigger 150993 is not a GRB
  4. Swift Trigger 150823 is HETE J1900.1-2455
  5. GRB 050817: Optical observations
  6. GRB 050815: Radio Observation
  7. GRB050814: Radio Observation
  8. GRB050817: Negative Optical Observations
  9. GRB 050814: continued fading
  10. GRB050815: XRT refined analysis
  11. GRB 050813: Radio Observations
  12. GRB050815: Refined analysis of the Swift-BAT burst
  13. GRB 050815: ROTSE-III Optical Limits
  14. GRB050815: Swift XRT afterglow localization
  15. GRB 050730: Third Epoch WSRT Radio Observations
  16. GRB050814: Fading red source
  17. GRB 050813: Gemini Spectra Revisited
  18. GRB050814: P60 Optical Afterglow Candidate
  19. GRB 050813: Non-fading of afterglow candidate
  20. GRB 050814: XRT refined analysis
  21. GRB050814: SWIFT/UVOT observation
  22. GRB050814: Refined analysis of the Swift-BAT burst
  23. GRB050813: Gemini Imaging
  24. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  25. GRB 050814: Swift XRT Afterglow Localization
  26. GRB 050814: Swift detection of a burst
  27. GRB 050813: Magellan detection of a high redshift galaxy cluster
  28. GRB050813: RTT150 optical observations
  29. GRB 050813: I-band observations
  30. GRB050813, SDSS pre-burst observations
  31. GRB 050813: KAIT optical limit
  32. GRB 050813: Swift-BAT refined analysis
  33. GRB 050813: Photometry of object in XRT error circle
  34. GRB050813: SWIFT/UVOT observation
  35. GRB 050813: Swift XRT afterglow localization
  36. RBO GRB 050714A and GRB 050716 observations
  37. Swift-BAT trigger 150131 is not a GRB
  38. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  39. GRB050803: CrAO optical observations, no OT candidate
  40. GRB 050730: WSRT Radio Observations
  41. GRB 050803: PROMPT BVRcIc Observations
  42. GRB 050807: ROTSE-III Optical Limits
  43. GRB 050730, optical observation
  44. GRB050805a : Null detection report
  45. GRB050730, optical observations
  46. GRB050803, optical observations
  47. GRB 050805b: TAROT optical limits
  48. GRB050802: TNG optical observations
  49. GRB050803: Radio Observation
  50. GRB 050803: RTT150 optical observations
  51. GRB050801: Radio Observation
  52. GRB050730: Radio Detection
  53. GRB050803: CrAO optical observations, possible OT candidate
  54. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  55. GRB 050803: Keck Observations
  56. GRB 050803: Swift-BAT refined analysis
  57. GRB 050802.422: Fading of the afterglow and detection of the host
  58. GRB050803: MASTER further analys
  59. GRB 050803, optical observations
  60. GRB 050803: Magellan Observations
  61. GRB 050803: early Swift XRT analysis results
  62. GRB050802: Tentative absorption redshift
  63. GCN GRB observation 050713A
  64. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  65. GRB 050802: Swift/UVOT optical and UV detections
  66. GRB050802: CrAO optical observations
  67. GRB050801: Unchanged decay slope
  68. GRB050802 radio non-detection
  69. GRB 050802: early Swift XRT analysis results
  70. GRB 050802: Swift/UVOT observations
  71. GRB 050802: Swift-BAT refined analysis
  72. GRB050801: Optical photometry and decay index
  73. GRB 050802: XRT position
  74. GRB 050802: Swift Gamma-ray Burst
  75. GRB050801: Swift/UVOT Optical and UV detections
  76. GCN 050801: early Swift XRT analysis results
  77. GRB 050801: Swift-BAT refined analysis
  78. GRB 050801, SMARTS optical/IR afterglow observations
  79. GRB 050801, afterglow observations
  80. GRB 050730, corrected photometry and break?
  81. GRB 050801: ROTSE-III Early Afterglow Break
  82. GRB050801: Swift-BAT detection of a burst
  83. GRB050801: GCN XRT position is incorrect
  84. GRB 050801: ROTSE-III Detection of Possible Counterpart
  85. GRB 050730: XRT refined analysis
  86. Correction to GCN Circ 3476 on GRB050525A
  87. GRB 050730: early TAROT optical observations
  88. GRB 050726: PROMPT Rc Observations
  89. GRB 050730: RTT150 optical observations
  90. Swift/UVOT photometry of GRB050730
  91. GRB 050730, spectra and optical photometry
  92. GRB050730: Refined BAT analysis of the Swift-BAT burst
  93. GRB 050730: Swift XRT afterglow observations
  94. GRB 050730 XMM-Newton observation
  95. GRB 050730: PROMPT VRcIc Observations
  96. GRB050730, afterglow observations
  97. GRB050730: confirmation of redshift
  98. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  99. GRB 050730, SMARTS optical/IR afterglow observations
  100. GRB050730: Liverpool Telescope optical observations

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