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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"
  1. OT 110215: NIR observations from NOT of GRB candidate
  2. GRB 110213A: optical observations in CrAO
  3. GRB 110213B: GROND observations of the optical/NIR afterglow
  4. GRB 110213A: optical observations in Mondy
  5. Fermi GBM trigger 319534757 (110216319) is not a GRB
  6. GRB110205A: EVLA Observations
  7. OT 110215: possible GRB from 2MASS J00264184+8324093
  8. Swift/UVOT observations of GRB110210a.
  9. GRB 110210A: optical upper limit
  10. GRB 110213B: Gemini South Redshift
  11. GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
  12. GRB 110210A: ROVOR Upper Limit
  13. GRB 110213A: YNAO-GMG Observations
  14. GRB 110213B: P60 Optical Afterglow Candidate
  15. GRB 110213A: TNT optical observations
  16. GRB110213A: RAPTOR Early Optical Peak and Plateau Measurements
  17. GRB 110212A: Swift XRT and UVOT observations
  18. Swift GRB110213A: interesting behaviour
  19. GRB 110213A: Fermi GBM observation
  20. GRB 110205A: Konkoly optical observations
  21. GRB 110213B: Swift XRT observation
  22. GRB 110213A: MITSuME Akeno Optical Observation
  23. Konus-Wind observation of GRB 110213A
  24. Konus-Wind observation of GRB 110213B
  25. GRB 110213A: Swift-XRT refined Analysis
  26. GRB 110213B: MAXI/GSC refined analysis
  27. GRB110213A: MITSuME Okayama Optical Observation
  28. GRB 110213A: Swift/UVOT refined analysis
  29. GRB 110213A: THO optical observations
  30. GRB 110213B: MAXI/GSC detection of a probable GRB
  31. GRB 110213A: Lightbuckets Optical Observations
  32. GRB 110213A, Swift-BAT refined analysis
  33. GRB 110213A: optical observations
  34. GRB 110213A: Enhanced Swift-XRT position
  35. GRB110212A: MITSuME Okayama optical upper limits
  36. GRB 110213A: KAIT observations
  37. GRB 110213A: GRAS011 optical observations
  38. GRB 110213A: Bok Telescope Redshift
  39. GRB 110213A: ROTSE-III Detection of Optical Counterpart
  40. GRB 110213A: P60 Optical Afterglow Detection
  41. GRB 110213A: Swift detection of a burst with optical afterglow
  42. GRB 110212A: GRT Optical Observation
  43. GRB 110212A, Swift-BAT refined analysis
  44. GRB 110212A: SARA-N Optical Limits
  45. GRB110212A: BOOTES-2/TELMA optical limits
  46. GRB 110212A: ROTSE-III Optical Limits
  47. GRB 110212A: Swift detection of a burst
  48. GRB 110201A: Subaru/MOIRCS Ks-band photometry
  49. Konus-Wind observation of GRB 110205A (correction to GCN 11659)
  50. GRB 110205A: detection of optical linear polarization from CAHA
  51. GRB 110207A: Suzaku WAM observation of the prompt emission
  52. GRB 110210A: optical upper limit
  53. GRB 110210A: Swift-XRT refined Analysis
  54. GRB 110205A: Swift/BAT and Suzaku/WAM joint spectral analysis
  55. GRB 110210A: Swift-BAT refined analysis
  56. Swift-BAT refined analysis of outburst from 1E 1841-04.5
  57. GRB 110210A: Enhanced Swift-XRT position
  58. GRB 110201A: optical observations
  59. GRB 110210A: Swift detection of a burst
  60. GRB 110206A: Swift-XRT confirmation of the X-ray afterglow
  61. GRB 110208A: Magellan confirmation of the optical afterglow
  62. Fermi GBM detection of a burst from 1E 1841-045
  63. Swift/UVOT observations of GRB110208a
  64. GRB 110205A: Suzaku WAM observation of the prompt emission
  65. GRB 110208A: Potential afterglow from Magellan
  66. GRB 110207A: Swift-XRT observations
  67. GRB 110208A: Swift-XRT refined Analysis
  68. GRB 110208A: Enhanced Swift-XRT position
  69. GRB 110208A: Swift-BAT refined analysis
  70. GRB 110208A: Magellan optical observations
  71. GRB 110206A: SMARTS optical/IR afterglow decay
  72. GRB 110208A: Swift detection of a burst
  73. SGR-like outburst from the magnetar 1E 1841-04.5
  74. GRB 110205A: optical observations in Mondy observatory
  75. GRB 110207A: Fermi GBM observation
  76. GRB 110205A : HCT optical observations
  77. GRB 110206A: Decay of afterglow candidate
  78. GRB 110206A: SMARTS optical/IR afterglow candidate observations
  79. GRB 110207A: TAROT Calern observatory optical observations
  80. GRB 110205A - Continued PAIRITEL NIR Observations
  81. GRB 110206A: GROND detection of afterglow candidate
  82. GRB 110207A: Swift-BAT refined analysis
  83. GRB 110205A: WSRT radio observation
  84. GRB 110206A: UVOT detection of afterglow candidate
  85. GRB110205A: CARMA 3mm Observations
  86. GRB 110207A: MASTER prompt and early optical observations
  87. Konus-Wind observation of GRB 110205A
  88. GRB 110207A: Swift detection of a burst
  89. GRB 110206A: Swift detection of a probable X-ray afterglow
  90. GRB 110206A: TAROT La Silla observatory optical observations
  91. GRB 110205A: Lightbuckets Optical Observations
  92. GRB 110206A: a long GRB detected by INTEGRAL
  93. GRB 110205A : Lulin optical observation
  94. GRB110205A: MITSuME Ishigakijima Optical Observation
  95. GRB110205A: MITSuME Okayama Optical Observation
  96. GRB110205A: SMA 1.3mm Observations
  97. GRB 110205A: Swift/UVOT Continuing Observations
  98. GRB 110205A: Lulin optical observations and temporal decay index
  99. Observations GRB 110205A
  100. GRB 110205A: Swift-BAT refined analysis

Advanced

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