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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

4952 results found.

  1. Swift Trigger 306745 is not a GRB
  2. GRB 080315: TAROT Calern observatory optical observations
  3. GRB 080310: ROTSE-III Observations of Optical Counterpart
  4. GRB080310: Optical observation by MITSuME telescope
  5. GRB 080310: PAIRITEL detection and PAIRITEL+KAIT+UVOT SED
  6. GRB 080310: Swift-XRT refined analysis
  7. GRB 080310: RRM optical photometry with the VLT
  8. GRB080310: Super-LOTIS suggestion of brightening
  9. GRB 080310, SMARTS optical/IR afterglow observations
  10. GRB080229, optical upper limit (Correction)
  11. GRB080229, optical upper limit
  12. GRB 080307: Early RAPTOR Limits
  13. GRB080307: Optical upper limits
  14. GRB 080303: REM NIR afterglow candidate
  15. ESO optical and NIR observations of GRB 080218B
  16. GRB 080218b, SMARTS optical/IR limits
  17. GRB 080121: Upper limit on X-ray afterglow
  18. GRB 071227: optical afterglow
  19. GRB 071227: Magellan observations
  20. GRB071227: Swift/UVOT refined analysis
  21. GRB 071129: Swift detection of a burst
  22. GRB 071122: Swift detection of a burst
  23. GRB071118 MITSuME OAO optical observation
  24. GRB071109: Super-LOTIS observations
  25. GRB071010b: optical observation
  26. GRB0711101: Two new source from Xinglong TNT observation
  27. GRB 071101: a nearby galaxy
  28. GRB 071031: Swift-XRT Team refined analysis
  29. GRB 071031: GROND detection in all bands
  30. GRB 071031: Swift detection of a burst with an optical counterpart
  31. GRB 071025: Kuiper Telescope Optical Observations
  32. GRB071021: MITSuME Okayama Optical Upper Limits
  33. GRB 071020: Swift-XRT refined analysis
  34. GRB 071020: Swift detection of a bright burst
  35. GRB 071013: TNT optical data refined analysis
  36. GRB 071010B correction to GCN 6892 optical observations
  37. GRB 071010B optical photometry
  38. GRB 071011: Optical afterglow candidate
  39. GRB 071010 REM NIR observations
  40. GRB 071010: Swift detection of a burst
  41. Recent SGR1806-20 Activity
  42. GRB 070923: Swift detection of a short hard burst
  43. GRB920925C: search for host galaxy
  44. Candidate Orphan GRB Optical Transient in IC 4779
  45. GRB 070810A: ROTSE-III Refined Analysis
  46. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  47. GRB 070729: Swift-XRT refined analysis
  48. GRB 070729: Magellan NIR Observations
  49. GRB 070729: Swift detection of a short hard burst
  50. GRB 070724B: Swift-XRT afterglow likely candidate
  51. GRB 070724B: Swift-XRT afterglow candidates
  52. GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
  53. GRB 070714B: Keck observations
  54. GRB 070714A: Swift-BAT T_zero
  55. GRB 070714A: Swift/UVOT Upper limits
  56. GRB 070714A: Swift XRT refined analysis
  57. GRB 070714b ("Bastille"): Optical Pre-Imaging (Clarification)
  58. GRB 070714 ("Bastille"): Optical Pre-Imaging
  59. GRB 070714 : Liverpool Telescope optical counterpart ?
  60. Swift detection of a possible burst (Trigger 284850)
  61. GRB 070628 Swift-UVOT Refined Analysis
  62. GRB070616: Optical Observation by MITSuME Akeno
  63. GRB 070616, Swift-BAT partial refined analysis
  64. SWIFT J195509.6+261406 (GRB 070610): further observations
  65. GRB 070612A: Super-LOTIS observations
  66. GRB 070612A: MDM Observations
  67. GRB 070517: Gemini optical imaging
  68. GRB 070509: ROTSE-III Optical Limits
  69. GRB 070429B: ROTSE-III Optical Limits
  70. GRB 070429B: Swift detection of a short burst
  71. LT monitoring of GRB070412
  72. GRB 070411 : Planned XMM-Newton observation
  73. GRB 070318, SMARTS optical/IR afterglow observations
  74. GRB 070411: TLS data shows plateau, flares
  75. GRB 070411: Swift/UVOT observations
  76. GRB 070411: Swift-XRT refined analysis
  77. GRB 070412: Optical observations at Crni Vrh
  78. GRB 070412: IAC80 optical afterglow candidate
  79. GRB 070412: Swift detection of a burst
  80. GRB 070411: Optical observations at Crni Vrh
  81. GRB 070411: Swift detection of a burst with optical afterglow
  82. GRB 070406: Swift XRT team further analysis
  83. GRB 070406: Swift XRT Team analysis - Possible X-ray counterpart
  84. GRB 070328: Suzaku WAM observation of the prompt emission
  85. GRB 070330, SMARTS optical/IR observations
  86. GRB 070330: TAROT La Silla observatory optical observations
  87. Konus-Wind observation of GRB 070328
  88. GRB 070328: Swift detection of a burst
  89. GRB 070311, deep optical photometry
  90. Short-Hard GRB 070209: PROMPT Observations
  91. GRB 070318: Swift detection of a burst with an optical afterglow
  92. GRB 070311: Optical Brightening
  93. GRB 070311: MDM Optical Follow-up
  94. GRB 070311: MDM Optical Detection
  95. GRB 070311: MITSuME Okayama Optical Observation
  96. GRB 070311: Swift-XRT refined analysis
  97. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  98. GRB 070311: REM candidate afterglow
  99. GRB 070309: A long GRB detected by INTEGRAL
  100. GRB 920925C: optical afterglow candidate

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