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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"

2744 results found.

  1. GRB101030A
  2. Optical observation of GRB 101024A
  3. GRB 101117B: Swift-BAT refined analysis
  4. Possible detection of INTEGRAL burst GRB 101112A by the EVLA
  5. GRB 090113, the review of the sky area in plate archives
  6. GRB 101030A: Swift-BAT refined analysis
  7. GRB 101030A: Swift detection of a burst
  8. GRB 090111, the review of the sky area in plate archives (1976-1996)
  9. GRB 101008A: correction to the GCN 11352
  10. GRB 101017A: Swift detection of a burst with optical counterpart
  11. GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
  12. GRB 101008A: MASTER prompt optical observations
  13. GRB 101008A: SAO RAS optical observations
  14. GRB 100924A: Fermi GBM observation
  15. GRB 100925A / MAXI J1659-152: Optical observation with the Kottamia 188cm telescope
  16. GRB 100925A/MAXI J1659-152: Submm observations from APEX
  17. GRB 100915A: Correction to Swift-BAT refined analysis
  18. GRB 100901A: errata of GRB name in GCN 11270
  19. GRB 100905A: UKIRT zJHK Observation
  20. GRB 100901A: Possible WSRT Radio Detection
  21. Optical observations of GRB 100901A
  22. GRB 100902A: GROND observations; afterglow candidate
  23. GRB 100901A: optical observation at Mt.Terskol
  24. GRB 100816A: 10.4-m GTC redshift confirmation
  25. GRB 100816A: VLT and Gemini-N revised redshift
  26. GRB 100816A : Lulin r'-band observation
  27. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  28. GRB 100805A: the 4-th epoch of SAO RAS optical observations
  29. GRB 100805A: Swift/UVOT Observations of a Possible Late-Time Brightening
  30. GRB 100805A: Swift-BAT refined analysis
  31. Trigger 430975: Swift detection of a possible burst
  32. GRB 100802A: Swift/UVOT Possible Optical Afterglow
  33. GRB 100802A: Liverpool Telescope observations
  34. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  35. GRB 100728A, Swift-BAT refined analysis
  36. GRB 100728B: Swift detection of a burst with an optical counterpart
  37. GRB 100727A: Swift detection of a burst
  38. GRB 100725B: refined XRT analysis
  39. GRB 100713A: optical observation in Maidanak
  40. GRB 100628A: Keck/LRIS Spectroscopy of Host Galaxy Candidate
  41. GRB 100628A: Near-IR sources coincident with the possible X-ray afterglow
  42. GRB 100628A: Swift XRT/UVOT refined analysis
  43. GRB 100615A: Additional Gemini/NIRI observations
  44. GRB 100702A, Swift-BAT refined analysis
  45. GRB 100628A: GROND optical/NIR observations of the host candidate
  46. GRB100625A: GROND confirmation of constant source
  47. GRB100628A: RTT150 optical observations
  48. GRB 100628A: Swift XRT detection of a possible X-ray afterglow
  49. GRB 100628A: INTEGRAL SPI-ACS light curve
  50. GRB 100621A: Swift/UVOT observations
  51. GRB 100514A: Swift/UVOT Observations
  52. Trigger 421695: Swift detection of a possible burst
  53. GRB 100508A: GROND Detection of the optical afterglow
  54. GRB 100508A: Swift detection of a burst
  55. Trigger 421072: Possible Swift detection of a GRB or transient
  56. GRB 100418A: RTT150 optical observations
  57. GRB 100418A: Possible Evidence for a Supernova
  58. Trigger 420256: Swift detection of a possible GRB
  59. GRB100418A: REM possible afterglow detection
  60. GRB 100413A: GMRT observation of radio afterglow
  61. GRB 100418A: Swift detection of a burst with a possible optical afterglow
  62. GRB 100414A: Swift-XRT detection of a possible X-ray afterglow
  63. GRB 100331B: Swift/XRT possible afterglow candidate
  64. GRB 100331B: SuperAGILE Localization of a Long GRB
  65. GRB 100322B or possible Galactic transient detected in ground analysis of BAT data
  66. Possible pulsation period in SGR 1833-0832
  67. GRB 100319A: Swift detection of a burst; possible SGR
  68. GRB 100316D: Possible Supernova
  69. GRB 100316D: Further Gemini observations
  70. GRB 100316 optical candidate from 1.23m CAHA telescope
  71. GRB 100316 optical candidate from 1.23m CAHA telescope
  72. GRB 100316A: Swift-XRT detection
  73. GRB 1000302A : A possible afterglow candidate
  74. GRB 100213A: Swift XRT refined analysis
  75. GRB 100213B: NOT optical observations
  76. GRB 100119A: Swift detection of a burst
  77. GRB100117A: Possible afterglow from NOT observation
  78. GRB 100115A: SARA Astrometry
  79. GRB 100115A: Swift-XRT candidate afterglow
  80. Swift/BAT Detects an Outburst from XTE J1901+014
  81. Swift Trigger 381591 is probably not a burst
  82. GRB 091231: GROND NIR observations
  83. Trigger 381591: Swift detection of a possible burst
  84. Trigger 381434: Swift detection of a possible burst
  85. GRB 091117: Swift-XRT late time observations
  86. Swift trigger 379449 (possible GRB) is not a burst
  87. GRB 091215: Faulkes Telescope North observations
  88. Trigger 379449: Swift detection of a possible burst
  89. GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
  90. GRB 091123: Fermi GBM detection of a very long burst
  91. Swift trigger 377436 (possible GRB 091130A) is not a burst
  92. GRB 091130: Swift detection of a possible burst
  93. GRB 091127: MASTER early optical transient polarimetry
  94. GRB 091117A: Swift/UVOT followup observations
  95. GRB 091117 BAT refined analysis
  96. GRB 091112: Swift detection of a possible burst
  97. GRB 091109A: GROND and VLT observations
  98. GRB 091109B: VLT observations
  99. GRB 091102: Swift/XRT localization
  100. GRB 091018: Skynet/PROMPT Observations of Possible Host Galaxy

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