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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"

18517 results found.

  1. GRB 120116A: Optical observations at Crni Vrh
  2. GRB 120116A: NOT observations
  3. GRB 120116A: IAC80 I-band observations
  4. GRB 120116A: Bassano Bresciano Observatory optical observations
  5. GRB 120116A: Swift detection of a burst
  6. GRB 111228A: optical observations
  7. AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
  8. GRB 120106A: optical upper limit
  9. Swift detection of an SGR burst from AXP 4U 0142+61
  10. GRB 120106A: Swift/UVOT Upper Limits
  11. GRB 120106A: Bassano Bresciano Observatory optical observations
  12. GRB 120106A: MITSuME Okayama Ks-band upper limit
  13. INTEGRAL Weak trigger #6433: GRT Optical Observation
  14. GRB 120106A: MITSuME Okayama Optical upper limits
  15. GRB 120106A: Enhanced Swift-XRT position
  16. GRB 120106A: TAROT Calern observatory optical observations
  17. GRB 120106A: Swift detection of a burst
  18. GRB111228A :LOAO R-band Observations
  19. GRB 111222A: Second Swift observation
  20. GRB111209A: ATCA detection at 5.5, 9, and 18GHz
  21. GRB 111228A: optical observations in CrAO
  22. GRB 120102A: Swift/UVOT Detection
  23. GRB 120102A: Enhanced Swift-XRT position
  24. GRB 120102A: Swift detection of a burst with an optical counterpart
  25. GRB 111225A: optical observations in CrAO
  26. GRB 111229A: Swift/UVOT Detection
  27. GRB 111229A: Enhanced Swift-XRT position
  28. GRB 111228A: Continued Skynet PROMPT/Dolomiti Optical Observations
  29. GRB 111229A: Gemini-South Redshift
  30. GRB 111229A: GROND afterglow candidate
  31. GRB 111229A: Swift detection of a burst
  32. GRB 111228A: Liverpool Telescope Observations
  33. GRB 111225A: Lightbuckets Optical Observations
  34. GRB 111228A: P60 Observations
  35. GRB 111228A: T100 observations
  36. GRB111228A: MITSuME Akeno photometry of the optical afterglow
  37. GRB 111228A: GMG optical observation
  38. GRB 111228A: Swift-XRT refined Analysis
  39. GRB 111228A: PAIRITEL NIR Detection
  40. GRB 111228A: TAROT La Silla observatory observations
  41. GRB 111228A: GROND observations
  42. GRB111228A: Errata of MITSuME Okayama about GRB name in GCNC 12743
  43. GRB 111228A: IAC80 BVI-band observations
  44. GRB 111228A: Swift/UVOT Detection
  45. GRB 111228A: Skynet/Dolomiti Optical Observations
  46. GRB 111228A: NOT optical observation
  47. GRB 111228A: optical observations
  48. GRB 111228A: Enhanced Swift-XRT position
  49. GRB 111228A: TAROT Calern observatory. OT decay stopped
  50. GRB 111228A, optical observations
  51. GRB111228A: MITSuME Okayama Optical Observation
  52. GRB 111228A: TAROT Calern observatory. OT seems still bright
  53. GRB 111228A: Possible host galaxy in the SDSS arhive
  54. GRB 111225A, optical observations
  55. GRB 111228A: Swift detection of a burst with an optical counterpart
  56. GRB 111205A: optical observations
  57. GRB 111225A: Swift/UVOT Observations
  58. GRB 111215A: Keck/LRIS Imaging
  59. GRB 111225A: Keck/LRIS Afterglow Photometry
  60. GRB 111225A: PAIRITEL NIR Upper Limits
  61. GRB111225A: MITSuME Okayama optical upper limits
  62. GRB 111225A: GRT Optical Observation
  63. GRB 111225A: 1.23m CAHA optical observations
  64. GRB 111225A: Enhanced Swift-XRT position
  65. GRB 111225A: Super-LOTIS early detection
  66. GRB 111225A: TAROT Calern observatory optical detection
  67. GRB 111225A: TAROT Calern observatory optical observations
  68. GRB 111225A: Swift detection of a burst with an optical counterpart
  69. GRB111222A: GMG optical observation
  70. GRB 111222A: Swift-XRT observations
  71. IPN Triangulation of GRB 111222A (short/hard/intense)
  72. GRB 111210A: optical upper limit of Mt. Terskol observatory
  73. Trigger 510075 is not a GRB
  74. GRB 111103B: optical upper limit
  75. GRB 110820A: optical observations in Maidanak observatory
  76. GRB 111103A: optical upper limit of Mt. Terskol observatory
  77. GRB 111211A: optical ovservations at Mt. Terskol observatory
  78. GRB111215A: optical upper limit
  79. GRB 111215B: Swift/UVOT Upper Limits
  80. GRB111215A: Pre-Outburst Palomar 48 inch Imaging
  81. GRB 111215A: WHT, LT and NOT imaging
  82. GRB 111215A: TNG K-band observations
  83. GRB 111215A: MITSuME Okayama Optical upper limits
  84. GRB 111215A: Swift/UVOT Upper Limits
  85. GRB 111215A: Swift-XRT refined Analysis
  86. GRB 111215A: Enhanced Swift-XRT position
  87. GRB 111215A: OSN I-band observations
  88. GRB 111215A: MASTER-Net optical prompt and follow up observations
  89. GRB 111215A, Optical Observations
  90. GRB 111209A: RAPTOR Limits Before and During the Gamma-ray Emitting Interval
  91. GRB 111215A: GMG optical upper limit
  92. GRB 111215A: Swift detection of a burst
  93. GRB 111212A: GROND observations
  94. GRB 111211A: NOT afterglow confirmation
  95. GRB 111211A: Swift/XRT target of opportunity observation
  96. GRB 111212A: Swift/UVOT Upper Limits
  97. GRB 111212A: Enhanced Swift-XRT position
  98. GRB 111212A: Swift-XRT observations
  99. GRB 111211A: GROND afterglow candidate
  100. GRB 111210A: GROND observations

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