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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"

45420 results found.

  1. GRB 120118B: Swift-XRT refined Analysis
  2. GRB 120118B : Lulin Optical limit
  3. GRB 120119A: MMT redshift confirmation
  4. GRB 120119A: Lick 3m Spectroscopy
  5. GRB 120119A: Gemini-S redshift
  6. GRB 120119A: PROMPT optical observation of early afterglow
  7. GRB 120119A: GROND Detection of the Optical/NIR Afterglow
  8. GRB 120118B: Swift/UVOT Upper Limits
  9. GRB 120119A: Liverpool Telescope afterglow detection
  10. GRB 120119A: PAIRITEL NIR Detection
  11. GRB 120119A: Swift detection of a burst with an optical counterpart
  12. GRB 120118B: NOT observations
  13. GRB 120118B: Enhanced Swift-XRT position
  14. GRB 120118B: Faulkes Telescope South observations
  15. XRF 120118A: early optical limit by "Pi of the Sky"
  16. GRB 120118B: Swift-XRT position
  17. GRB 120118B: MASTER optical observations
  18. GRB 120118B: Swift detection of a burst
  19. XRF 120118A: Optical candidate
  20. XRF 120118A: further INTEGRAL analysis
  21. XRF 120118A: an X-Ray Flash detected by INTEGRAL
  22. GRB 120116A: Swift/UVOT Upper Limits
  23. GRB 120116A: Swift-XRT refined Analysis
  24. GRB 120116A: Enhanced Swift-XRT position
  25. AXP 4U 1042+61: Mondy optical observations
  26. GRB 120116A: Mondy optical observations
  27. GRB 120116A: Gemini optical/IR candidate
  28. GRB 120116A: EVLA observations
  29. GRB 120116A: WHT optical observations
  30. GRB 120116A: Optical observations at Crni Vrh
  31. GRB 120116A: Swift-BAT refined analysis
  32. GRB 120116A: NOT observations
  33. GRB 120116A: IAC80 I-band observations
  34. GRB 120116A: Bassano Bresciano Observatory optical observations
  35. GRB 120116A: MASTER Early optical limit
  36. GRB 120116A: Swift detection of a burst
  37. GRB 120114A found in ground analysis of BAT data
  38. GRB 111228A: optical observations
  39. AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
  40. GRB 120106A: optical upper limit
  41. Swift detection of an SGR burst from AXP 4U 0142+61
  42. GRB 120107A: Suzaku WAM observation of the prompt emission
  43. GRB 110915B, the review of the sky area in plate archives
  44. GRB 120107A: Fermi GBM observation
  45. GRB 120106A: MITSuME Okayama Optical Observation (update)
  46. Konus-Wind observation of GRB 120107A
  47. IPN Triangulation of GRB 120107A
  48. GBM trigger 347620337 (GRB 120107A?) : High-energy photon emission in Fermi/LAT data
  49. GRB 120106A: Swift/UVOT Upper Limits
  50. GRB 120106A: Bassano Bresciano Observatory optical observations
  51. GRB 120106A: MITSuME Okayama Ks-band upper limit
  52. GRB 120106A: MASTER Early OT marginally detection
  53. GRB 120106A: Swift-XRT refined Analysis
  54. INTEGRAL Weak trigger #6433: GRT Optical Observation
  55. GRB 120106A: Swift-BAT refined analysis
  56. GRB 120106A: MITSuME Okayama Optical upper limits
  57. GRB 120106A: Enhanced Swift-XRT position
  58. GRB 120106A: TAROT Calern observatory optical observations
  59. GRB 120106A: MASTER-Tunka optical observations
  60. GRB 120106A: Swift detection of a burst
  61. GRB111228A :LOAO R-band Observations
  62. GRB 111225A, the review of the sky area in plate archives
  63. GRB 111222A, the review of the sky area in plate archives
  64. GRB 111222A: Fermi GBM observations
  65. GRB 111222A: Second Swift observation
  66. GRB111209A: ATCA detection at 5.5, 9, and 18GHz
  67. GRB111225A: RAPTOR Early Detection of the Optical Counterpart
  68. GRB 111211A: Detection of the SN with the 10.4m GTC
  69. GRB 120102A: Fermi GBM observation
  70. Konus-Wind observation of GRB 120102A
  71. GRB 120102A: Swift-BAT refined analysis
  72. GRB 111228A: optical observations in CrAO
  73. GRB 120102A: Swift-XRT refined Analysis
  74. GRB 120102A: Swift/UVOT Detection
  75. GRB 120102A: Enhanced Swift-XRT position
  76. GRB 120102A: Swift detection of a burst with an optical counterpart
  77. GRB 111225A: optical observations in CrAO
  78. GRB 111228A, optical observations
  79. GRB 111228A: LOAO Optical Observation
  80. Konus-Wind observation of GRB 111228A
  81. GRB 111228A: MASTER-Net optical photometry
  82. GRB 111228A: correction for GCN 12787
  83. GRB 111228A: Optical and NIR observations with Kanata telescope
  84. GRB 110915A, the review of the sky area in plate archives
  85. GRB 111228A: SMARTS optical/IR afterglow observations
  86. GRB 111229A: Swift/UVOT Detection
  87. GRB 111229A: Faulkes Telescope South observations
  88. GRB 111229A: Swift-XRT refined Analysis
  89. GRB 111229A: Enhanced Swift-XRT position
  90. GRB 111228A: Continued Skynet PROMPT/Dolomiti Optical Observations
  91. GRB111228A: Further GMG observations
  92. GRB 111229A: Gemini-South Redshift
  93. GRB 111229A: Swift-BAT refined analysis
  94. GRB 111229A: GROND afterglow candidate
  95. GRB 111229A: Swift detection of a burst
  96. GRB 111228A: Liverpool Telescope Observations
  97. GRB 111225A: Lightbuckets Optical Observations
  98. GRB 111228A: P60 Observations
  99. GRB 111228A: X-shooter spectroscopy
  100. GRB 111228A: T100 observations

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