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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. GRB 120803A: Swift-XRT Observations
  2. GRB 120803A: Swift-BAT refined analysis
  3. GRB 120803B: FTN possible afterglow candidate
  4. GRB 120803B: Swift detection of a burst
  5. GRB 120803A: Swift detection of a possible burst
  6. GRB 120802A: GRT Optical Observation
  7. GRB 120802A: Swift-XRT refined Analysis
  8. GRB 120802A Gemini-N redshift
  9. GRB 120802A: APEX/LABOCA submm observations
  10. GRB 120729A: Fermi GBM observation
  11. GRB 120802A: Swift-BAT refined analysis
  12. GRB 120802A: Enhanced Swift-XRT position
  13. GRB 120802A: MASTER optical observations
  14. GRB 120802A: optical uper limit in ISON-NM observatory
  15. GRB 120802A: Swift detection of a burst
  16. GRB 120729A: JCMT SCUBA-2 sub-mm observation
  17. GRB 120728B: Fermi GBM detection
  18. Konus-Wind observation of GRB 120728B
  19. GRB 120729A: break in the optical light curve
  20. GRB 120729A: Optical observations from OSN, BOOTES1/2 and IAC80
  21. IPN Triangulation of GRB 120728B (long/intense)
  22. GRB 120729A: RTT150 optical observations
  23. GRB 120729A: EVLA Observations
  24. Virtual Telescope observations of GRB 120729A
  25. GRB 120729A: Early RAPTOR Observations
  26. GRB 120729A: UKIRT Observation
  27. T100 observations of GRB 120729A
  28. GRB 120728A: GROND Afterglow discovery
  29. GRB 120729A: Swift-XRT refined Analysis
  30. Correction to Swift GCN Circular 13538
  31. GRB 120729A: Swift/UVOT Detection
  32. Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB
  33. GRB 120729A: Xinglong TNT optical upper limit
  34. GRB 120729A, Swift-BAT refined analysis
  35. GRB 120728A, Swift-BAT refined analysis
  36. GRB 120729A: Enhanced Swift-XRT position
  37. GRB 120728A: Swift/UVOT Upper Limits
  38. GRB 120729A Gemini-N redshift
  39. GRB120729A - Faulkes Telescope North Optical Afterglow Candidate
  40. GRB 120729A: Swift detection of a burst with an optical afterglow
  41. GRB 120728A: Swift-XRT refined Analysis
  42. GRB 120728A: Enhanced Swift-XRT position
  43. Trigger 529076: Swift possible detection of SwJ1910.2-0546
  44. GRB 120728A: GROND observations
  45. GRB 120728A: Swift detection of a burst
  46. GRB 120727A/Galactic source: Fermi-LAT detection of a transient source
  47. GRB 120716A: optical observation in Maidanak observatory
  48. Swift Trigger 528925 is probably a noise fluctuation
  49. GRB 120722A: optical upper limit
  50. GRB 120724A: optical observation in Maidanak observatory
  51. GRB 120724A: JCMT SCUBA-2 sub-mm observation
  52. GRB 120716A: optical observation in CrAO
  53. GRB 120724A, Swift-BAT refined analysis
  54. GRB 120724A: Swift/UVOT Detection of the Optical Afterglow
  55. GRB 120724A: Enhanced Swift-XRT position
  56. GRB 120724A: Swift-XRT refined Analysis
  57. GRB120711A: Planned XMM-Newton observation
  58. GRB 120724A: Gemini-N tentative redshift
  59. GRB 120724A: FTN optical afterglow candidate
  60. GRB 120724A: Swift detection of a burst
  61. GRB 120709A: Swift re-observation of the field of the X-ray counterpart candidate.
  62. GRB 120722A: Swift/UVOT Upper Limits
  63. GRB 120722A: VLT/X-shooter redshift of the host galaxy
  64. GRB 120722A: GROND detection of the afterglow
  65. GRB 120722A: 1.5m OSN I-band observations
  66. GRB 120722A: Swift-XRT refined Analysis
  67. GRB 120722A: Swift-BAT refined analysis
  68. GRB 120722A: Enhanced Swift-XRT position
  69. GRB 120722A: Correction for GCN circ.13500
  70. GRB 120722A: Xinglong TNT optical afterglow candidate
  71. GRB 120722A: Swift detection of a burst
  72. GRB 120716A: Fermi GBM observation
  73. GRB 120716A: EVLA Detection
  74. GRB 120716A: Swift-XRT detection
  75. GRB 120716A: Swift/XRT position consistent with that of the optical counterpart
  76. GRB 120716A: Redshift confirmation from VLT/X-shooter
  77. VLT/FORS2 redshift of GRB120716A
  78. GRB 120716A: GROND confirmation of the optical/NIR afterglow
  79. GRB 120716A: Typo correction in GCN 13490
  80. GRB 120716A: Optical decay from NOT
  81. GRB 120716A: Candidate Optical Afterglow from PTF
  82. Konus-Wind observation of GRB 120716A
  83. IPN Triangulation of unusual GRB 120716A
  84. Fermi GBM trigger 120716.498 is not a GRB
  85. GRB 120711A: ATCA 34GHz final observations (upper limit)
  86. GRB 120714B: Swift/UVOT Detection
  87. GRB 120714B: Swift-XRT refined Analysis
  88. GRB120714A: Swift/UVOT upper limits
  89. GRB 120714B: Swift-BAT refined analysis
  90. Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
  91. GRB 120714A: GROND upper limits
  92. GRB 120714B: GROND confirmation of fading afterglow
  93. GRB 120714B: Redshift from VLT/X-shooter
  94. GRB 120714A: Swift-XRT refined Analysis
  95. Trigger 526660: Swift detection of 1 E 1841-045 (aka Kes 73)
  96. GRB 120624B: VLA Observations
  97. GRB 120714B: Position Correction and Candidate Optical Afterglow
  98. GRB 120714A: Swift-BAT refined analysis
  99. GRB 120714B: Swift detection of a burst
  100. GRB 120714A: Enhanced Swift-XRT position

Advanced

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