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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"

2803 results found.

  1. GRB 121027A: Swift/UVOT Possible Detection
  2. GRB 121025A: Swift-XRT observation
  3. Swift Trigger 536502 is likely a noise fluctuation in coincidence with SAX J1818.6-1703
  4. Trigger 535733: Swift possible detection of SAX J1828.5-1037
  5. Swift Trigger 535026: Optical decay confirmation with IAC80 and BOOTES-2/TELMA.
  6. GRB 121001A: possible optical counterpart
  7. Swift Trigger 535026: Galactic Transient or possible GRB
  8. GRB 120927A: GROND upper limits
  9. Swift Trigger 533836 is a new Galactic transient
  10. GRB 120909A: Swift-BAT refined analysis
  11. GRB 120821A: Swift/XRT observations
  12. GRB 120804A: Possible temporal break in the X-ray light-curve
  13. Swift Trigger 530581: GRB 120811A or a galactic transient
  14. GRB 120803A: optical upper limit
  15. GRB 120805A: 1.23m CAHA observations
  16. GRB 120803A: Swift-BAT refined analysis
  17. GRB 120803B: FTN possible afterglow candidate
  18. GRB 120803A: Swift detection of a possible burst
  19. Trigger 529076: Swift possible detection of SwJ1910.2-0546
  20. Swift Trigger 528925 is probably a noise fluctuation
  21. GRB 120724A: optical observation in Maidanak observatory
  22. GRB 120724A: Gemini-N tentative redshift
  23. GRB120714A: Swift/UVOT upper limits
  24. GRB 120711A: Swift/UVOT Observations
  25. GRB 120711A: a possible X-ray transient
  26. Swift Trigger 525554 is probably not a GRB
  27. Swift Trigger 524949: Noise fluctuation near a galaxy
  28. GRB 120521C: Early Tautenburg limits
  29. GRB 120514A: Swift-BAT refined analysis
  30. Fermi Trigger 358364818: BOOTES-4 observations
  31. GRB 120510B/Fermi Trigger 358364818: MASTER possible OT candidate
  32. GRB 120510A: Swift XRT and UVOT observations
  33. GRB 120422A: i-band re-brightening and possible SN detection
  34. GRB 120422A: optical observations
  35. GRB 120422A, the review of the sky area in plate archives
  36. GRB 120422A: Gemini redshift of candidate host
  37. GRB 120326A, the review of the sky area in plate archives
  38. GRB 120402A: optical upper limit
  39. GRB 120402A: Swift detection of a possible burst or noise
  40. GRB 120324A, the review of the sky area in plate archives
  41. Swift trigger 518853: MASTER-ICATE possible OT
  42. GRB 120327A: Gemini-South redshift
  43. GRB 120326A: Swift-BAT refined analysis
  44. GRB 120324A: Swift-BAT refined analysis
  45. GRB 120324A: Liverpool Telescope optical candidate
  46. GRB 120320A, the review of the sky area in plate archives
  47. GRB 120320A, Swift-BAT refined analysis
  48. GRB 111228A: possible detection of the SN with the TNG
  49. GRB 120302A: Swift XRT refined analysis
  50. GRB 120312A, the review of the sky area in plate archives
  51. GRB 120311A, the review of the sky area in plate archives
  52. GRB 120302A, the review of the sky area in plate archives
  53. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  54. GRB 120305A: Swift-BAT refined analysis
  55. GRB 120219A, the review of the sky area in plate archives
  56. GRB_120215, the_review_of_the_sky_area_in_plate_archives
  57. GRB 120212A: Errata of subject in GCNC 12936
  58. GRB 120202A, the review of the sky area in plate archives
  59. GRB 111228A, the review of the sky area in plate archives
  60. GRB 111228A: Possible host detected by Swift/UVOT
  61. GRB 120116A, the review of the sky area in plate archives
  62. GRB 120121A: Swift-XRT position
  63. GRB 120102A, the review of the sky area in plate archive
  64. GRB 110915B, the review of the sky area in plate archives
  65. GRB 111225A, the review of the sky area in plate archives
  66. GRB 111222A, the review of the sky area in plate archives
  67. GRB 111211A: Detection of the SN with the 10.4m GTC
  68. GRB 120102A: Swift-BAT refined analysis
  69. GRB 110915A, the review of the sky area in plate archives
  70. GRB 111229A: Swift detection of a burst
  71. GRB 111228A: Possible host galaxy in the SDSS arhive
  72. GRB 111225A: Swift-XRT refined Analysis
  73. GRB 111205A: Confirmation of X-ray Afterglow
  74. Possible detection of pre-trigger X-ray emission from GRB 111215A by MAXI/GSC
  75. GRB 111215A: Swift-BAT refined analysis
  76. GRB 111201A, the review of the sky area in plate archive
  77. GRB 111209A: VLT/X-shooter redshift
  78. GRB 111205A: GROND observations
  79. GRB 111123A: optical upper limit in CrAO: correction to the GCN circ. 12613
  80. GRB 111123A, Swift-BAT refined analysis
  81. GRB 111123A: TNG NIR detection of the afterglow candidate
  82. GRB 111117A, the review of the sky area in plate archives
  83. GRB 111117A: TNG observations
  84. GRB111107A: Further ATCA observations - no detection
  85. GRB111107A: ATCA observations - upper limit and a possible detection
  86. GRB 111109A: Swift-BAT refined analysis
  87. GRB 111107A: Swift-BAT refined analysis
  88. GRB 111103B : WIYN 3.5m NIR observations
  89. GRB 111022B: BTA Optical Observations
  90. GRB 111020A Spectral lag analysis
  91. GRB 110918A: Optical light curve for days 1.4 to 16.3
  92. GRB 111016A: Swift-BAT refined analysis
  93. GRB 111016A: P60 Afterglow Candidate
  94. GRB 111016A: Swift detection of a burst
  95. GRB 111005A: EVLA Observations
  96. GRB 110924A: Swift detection of a possible burst
  97. GRB 110918A optical observation
  98. GRB 110903A: Suzaku WAM observation of the prompt emission
  99. GRB 110825A: Further Swift/XRT Observations
  100. MAXI J1836-194 (originally GRB 110905A): Swift-BAT refined analysis

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