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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"

2793 results found.

  1. GRB 120224A: Swift detection of a burst
  2. GRB 1202019A: optical observation in Mondy observatory
  3. GRB 120219A: MITSuME Okayama Optical upper limits
  4. GRB 120215A: Swift-BAT refined analysis
  5. GRB 120215A: Swift detection of a burst
  6. GRB 120211A: Swift-BAT refined analysis
  7. Swift detection of a burst from LS I +61 303
  8. GRB 120127A: MAXI/GSC detection of a probable GRB
  9. AXP 4U 1042+61: Mondy optical observations
  10. GRB 120116A: Optical observations at Crni Vrh
  11. AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
  12. Swift detection of an SGR burst from AXP 4U 0142+61
  13. GRB 111228A: MASTER-Net optical photometry
  14. GRB 111228A: Optical and NIR observations with Kanata telescope
  15. GRB 111225A: Lightbuckets Optical Observations
  16. GRB 111228A: X-shooter spectroscopy
  17. GRB111228A: MITSuME Akeno photometry of the optical afterglow
  18. GRB 111228A: GMG optical observation
  19. GRB111228A: MITSuME Okayama Optical Observation
  20. GRB 111228A: Swift detection of a burst with an optical counterpart
  21. Trigger 510075 is not a GRB
  22. GRB 111215A: MASTER-Net optical prompt and follow up observations
  23. GRB111210A: MITSuME Okayama J-band upper-limit
  24. GRB 111209A, Swift-BAT refined analysis
  25. GRB 111209A: Swift detection of a long burst with an optical counterpart
  26. GRB 111121A: Suzaku WAM observation of the prompt emission
  27. IPN Triangulation of GRB 111113A (short/hard/intense)
  28. Continued Skynet observations of GRB111107A
  29. Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
  30. GRB 111022B: MASTER OT observations
  31. GRB 111029A: KAIT optical limits
  32. GRB 111029A: optical upper limit
  33. GRB 111029A: Swift detection of a burst
  34. GRB 111026A: Swift detection of a burst
  35. GRB 111022A: MITSuME Akeno Optical upper limits
  36. GRB 111022A: MASTER-Net early limit
  37. GRB 111018A: GROND Upper Limits
  38. GRB 110928A: Swift-XRT observations
  39. Fermi GBM triggers 110923481, 110924391 and 110925200 are not GRBs
  40. GRB 110921A: Swift-XRT refined Analysis
  41. MAXI/GSC detection of a short soft X-ray transient
  42. GRB 110825A: Suzaku WAM observation of the prompt emission
  43. GRB 110827A: Swift detection of a burst
  44. GRB110820A: MITSuME Ishigakijima Optical Upper Limits
  45. GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
  46. IPN triangulation of GRB 110808B (short/hard/intense)
  47. GRB 110726A: Swift-XRT refined Analysis
  48. GRB110731A: MOA optical observations of the steeply fading afterglow
  49. GRB 110801A: MASTER OT observations
  50. AXP 4U 0142+61: Fermi GBM detection
  51. INTEGRAL Weak trigger #6331: GRT Optical Observation
  52. AXP 4U 0142+61: Swift-BAT refined analysis
  53. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  54. Konus-Wind observation of GRB 110721A
  55. GRB 110721A: Fermi-LAT detection
  56. GRB 110721A: Fermi GBM detection
  57. Swift J1822.3-1606 : Fermi GBM observation
  58. Swift J1822.3-1606: A Probable New SGR in Ground Analysis of BAT Data
  59. Konus-Wind observation of GRB 110708B
  60. Swift Trigger 457076: a possible GRB
  61. Swift-BAT trigger 456532 is not astrophysical
  62. GRB 110625A: NIR Source
  63. Konus-Wind observation of GRB 110618A
  64. IPN triangulation of GRB110618A (long duration, extremely intense)
  65. GRB 110610A: Suzaku WAM observation of the prompt emission
  66. GRB 110521A: Swift detection of a burst
  67. GRB 110422A: Update of Herschel FIR observation schedule
  68. GRB 110428A : Swift-XRT observations
  69. GRB 110428A: Fermi-LAT Detection
  70. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  71. GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
  72. GRB 110328A / Swift J164449.3+573451: X-ray analysis and a mini-blazar analogy
  73. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  74. GRB 110319A: Swift-XRT refined Analysis
  75. GRB 110305A: Swift detection of a burst
  76. GRB 110223A: Liverpool Telescope observations
  77. OT 110215: possible GRB from 2MASS J00264184+8324093
  78. GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
  79. GRB 110213B: P60 Optical Afterglow Candidate
  80. GRB 110212A: Swift XRT and UVOT observations
  81. GRB 110213B: Swift XRT observation
  82. GRB 110213B: MAXI/GSC refined analysis
  83. GRB 110213B: MAXI/GSC detection of a probable GRB
  84. GRB 110210A: Swift detection of a burst
  85. GRB 110207A: Swift-BAT refined analysis
  86. GRB 110205A: Possible Lick/Kast redshift
  87. GRB 110128A: Swift detection of a burst
  88. GRB 101225A: CQUEAN optical observation
  89. GRB 110107A: Swift-XRT afterglow confirmation
  90. Short GRB 110106A: MASTER OT observations
  91. GRB 110106B: Gemini-North / WHT detection of a fading afterglow
  92. GRB 110106B: WHT candidate afterglow
  93. GRB101224A: MITSuME Okayama optical upper limits
  94. IPN triangulation of bright GRB 101123A
  95. GGRB 101023A: GROND detection of the optical-NIR afterglow
  96. GRB 101017A: Swift detection of a burst with optical counterpart
  97. Konus-Wind observation of GRB 101014A
  98. GRB 101014A: Fermi GBM detection
  99. MAXI J1659-152: Swift-BAT refined analysis (triggers 434928 and 434931)
  100. GRB 100915A: TAROT Calern observatory optical observations

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