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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"

32720 results found.

  1. Further Retractions of previous Swift-BAT triggers
  2. GRB 070110: VLT absorption redshift
  3. GRB 070110: UVOT Observations of a Candidate Afterglow
  4. GRB070110: Swift XRT Team refined analysis
  5. GRB 070110, Swift-BAT refined analysis
  6. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  7. GRB070107: Swift/XRT refined analysis
  8. GRB 070107: Possible UVOT Afterglow
  9. GRB 070107, Swift-BAT refined analysis
  10. GRB 070107: Swift/XRT position
  11. VLA observation of GRB 061222B
  12. VLA detection of GRB 061222A
  13. GRB070103: APO SPIcam i' and z' limits
  14. GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
  15. GRB070103: KPNO 4m+FLAMINGOS J limit
  16. GRB 070103: Swift/UVOT Upper limits
  17. GRB070103: Swift XRT refined analysis
  18. GRB 070103, Swift-BAT refined analysis
  19. GRB 070103: NOT observations
  20. Retractions of previous Swift-BAT triggers
  21. GRB061222a: optical observations
  22. Konus-Wind observation of GRB 061222A
  23. GRB 061210: Swift/XRT Astrometry Correction
  24. GRB 050826: MDM Redshift
  25. GRB 061222B: TAROT La Silla observatory early optical observations
  26. GRB 061218: TAROT La Silla observatory early optical observations
  27. GRB 061222A: MITSuME Akeno optical upper limits
  28. GRB 061222A: Confirmation of Gemini Afterglow Candidate
  29. GRB 061222B: MITSuME Akeno optical upper limits
  30. GRB 061222A: Gemini Afterglow Candidate
  31. GRB 061222B, Swift-BAT refined analysis
  32. GRB061222A Swift/UVOT: Upper Limits
  33. GRB 061222B: Swift/UVOT Upper limits
  34. GRB 061222B: Observation with the KANATA 1.5m telescope
  35. GRB061222B: Swift-XRT Refined Analysis
  36. GRB 061222A: Observation with the KANATA 1.5m telescope
  37. GRB 061222B: BOOTES-IR optical observations
  38. GRB 061222B: SARA upper limit
  39. GRB 061222A: Swift-XRT refined analysis
  40. GRB 061217: Magellan host galaxy redshift
  41. GRB 061222A, Swift-BAT refined analysis
  42. GRB 061222B: REM NIR/optical observations
  43. GRB 061222b, SMARTS optical/IR afterglow observations
  44. GRB 061222B: TAROT La Silla observatory afterglow observation
  45. GRB 061222b: Magellan redshift
  46. GRB 061222B: Swift detection of a burst
  47. GRB 061222A: Prompt ROTSE-III Optical Limits
  48. GRB 061201: Magellan redshift of nearby galaxy
  49. GRB 061217: Confirmation of host candidate
  50. GRB 061217: Object ib GCN 5948 is a star
  51. GRB 061217: Extended object in the revised XRT error circle
  52. GRB 061217, Candidate host galaxy
  53. GRB 061217 - Swift/XRT position correction
  54. GRB 061210: Possible Host Galaxy (S2-G2) Keck Spectrum
  55. GRB 061201: Correction to GCN 5944
  56. GRB 061201: Magellan Redshift of nearby Abell cluster
  57. GRB 061218: TAROT La Silla observatory optical observations
  58. GRB 061217: TAROT Calern observatory optical observations
  59. GRB 061218: TORTOREM optical upper limits
  60. GRB 061218, Swift-BAT refined analysis
  61. GRB061217: VLT NIR observations
  62. GRB 061218, SMARTS optical/IR observations
  63. GRB 061218: REM prompt observations
  64. GRB 061217, SMARTS optical observations
  65. GRB061217: Swift/UVOT refined analysis.
  66. GRB 061217: optical observations at Calar Alto
  67. GRB061217 - Swift/XRT refined analysis
  68. GRB 061217, Further Swift-BAT refined analysis of the short hard burst
  69. GRB 061217, Swift-BAT refined analysis
  70. GRB 061217: Magellan Observations
  71. GRB 061217: REM prompt observations
  72. GRB 061217: ROTSE-III Optical Limits
  73. GRB 061210: MDM Follow-up Observation
  74. GRB061210: Swift/UVOT observations
  75. Swift-BAT Trigger 250908 is a Cosmic Ray Shower event
  76. GRB 061210: Optical sources near XRT positions
  77. GRB 061210: Swift XRT analysis - Possible counterparts
  78. GRB 061210 : Faulkes North Telescope optical limit
  79. GRB 061214(?): ROTSE-III Optical Limits
  80. GRB 061210: Suzaku WAM observation of the prompt emission
  81. Swift/BAT trigger #250033 is due to a known source during loss of
  82. GRB 061213: MASTER-VWF-Kislovodsk OT candidate retraction
  83. GRB 061210: Gemini/GMOS Observations
  84. GRB 061126: Radio Observations
  85. GRB061210: Radio Observations
  86. GRB061201, VLT optical decay: correction
  87. GRB 061126: a GRB detected off-axis by INTEGRAL
  88. GRB 061202: Suzaku WAM observation of the prompt emission
  89. GRB 061210: MDM Observation
  90. GRB 061210, Swift-BAT refined analysis of the SHB
  91. GRB 061210: Swift-BAT detection of a short burst
  92. Optical Afterglow observations of GRB 061126
  93. GRB061126: optical observations
  94. GRB 060926: MASTER: discovery of the optical flare
  95. GRB061126: update on the Swift-XRT afterglow light curve
  96. Corrections for Swift/UVOT Exposure Times for GRBs 061110B and 061121
  97. GRB 061201: UVOT Observations of a Fading Optical Afterglow
  98. GRB 061202: TORTOREM optical upper limits
  99. GRB 061201: VLT optical decay
  100. GRB 061201: SOAR Confirmation of Candidate Afterglow

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