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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

45742 results found.

  1. GRB 140408A: Withdrawal of afterglow candidate
  2. GRB 140529A found in ground analysis of BAT slew data
  3. IPN Triangulation of GRB 140528A
  4. Chandra late-time observations of GRB140515A
  5. Swift Trigger 600114 in M31: UVOT Observations
  6. Swift trigger 600114 is not an outbursting X-ray source
  7. Swift Trigger 600114: Optical spectroscopy from GTC
  8. Swift Trigger 600114: Preliminary BAT analysis
  9. Swift Trigger 600114 in M31: Archival and Prompt UVOT Imaging
  10. Swift detection of a bright X-ray source in M31
  11. Fermi GBM trigger 422752719/ 140525971 is not a GRB
  12. Swift detection of SFXT IGR J17544-2619
  13. GRB 140523A: NOT observation
  14. Konus-Wind observation of GRB 140523A
  15. IPN Triangulation of GRB 140523A
  16. GRB 140523A: Nanshan optical upper limit
  17. Swift trigger 599860 probably not real
  18. GRB 140523A: possible X-ray afterglow candidate from tiled Swift/XRT observations
  19. GRB 140523A Tiled Swift observations
  20. GRB 140523A: Fermi-LAT detection
  21. GRB 140523A: Fermi GBM detection
  22. GRB 140521A : Xinglong TNT upper limit
  23. GRB 140521A: Fermi GBM Detection
  24. GRB 140423A: TShAO optical observations
  25. GRB 140521A: AAO optical observations
  26. GRB 140521A: Swift-BAT refined analysis
  27. GRB 140521A: AROMA-N Optical Observation
  28. GRB 140521A: MITSuME Okayama upper limits
  29. GRB 140516A: further Swift-XRT analysis
  30. GRB 140521A: MASTER optical observations
  31. GRB 140521A: Swift detection of a burst
  32. GRB 140512A: Redshift from NOT
  33. GRB 140518A: T100 observations
  34. GRB 140518A: Continued RATIR Optical and NIR Observations
  35. GRB 140512A: MASTER prompt and afterglow optical observations
  36. GRB 140518A, Swift-BAT refined analysis
  37. GRB 140518A: Swift-XRT refined Analysis
  38. GRB 140518A: Skynet GORT Detections of the Optical Afterglow
  39. GRB 140518A: Swift/UVOT Upper Limits
  40. GRB 140518A: RATIR Optical and NIR Observations
  41. GRB 140518A: Gemini-N redshift
  42. GRB 140518A: P60 i-/z-band detections
  43. GRB 140518A: KAIT optical candidate
  44. GRB 140518A: Swift detection of a burst
  45. GRB 140516A: RATIR Optical and NIR Observations
  46. GRB 140516A: Subaru NIR imaging observations
  47. GRB 140516A: 6 GHz upper limit
  48. GRB 140516A: Gemini-North limit on an optical afterglow
  49. GRB 140516A: Swift/UVOT Upper Limits
  50. GRB 140516A: Swift-BAT refined analysis
  51. GRB 140516A: Swift-XRT refined Analysis
  52. GRB 140516A: NOT optical observations
  53. GRB 140516A: Enhanced Swift-XRT position
  54. GRB 140516A: MASTER early optical observations
  55. GRB 140516A: ISON-Kislovodsk optical observations
  56. GRB 140516A: TNG optical observations
  57. GRB 140516A: Swift detection of a short burst
  58. GRB 140515A: Swift-BAT refined analysis
  59. GRB 140515A: VLA Detection
  60. GRB 140515A : TNG near-infrared observations
  61. GRB 140419A: Continued Mondy optical observations
  62. GRB 140515A: GROND observation of the afterglow
  63. GRB 140515A: Spectroscopy from the 10.4m GTC
  64. GRB 140515A: Optical observations from the 2.5 m NOT
  65. GRB 140515A: Swift-XRT refined Analysis
  66. GRB 140515B: MAXI/GSC detection
  67. GRB 140515A: KAIT Optical Upper Limit
  68. GRB 140515A: Gemini-North imaging
  69. GRB 140515A: Swift/UVOT Upper Limits
  70. GRB 140423A: HCT optical observations
  71. GRB 140515A: MITSuME Akeno upper limits
  72. GRB 140515A: Enhanced Swift-XRT position
  73. GRB 140515A: Gemini-N redshift
  74. Trigger 599041: Swift detection of SFXT IGR J16479-4514
  75. GRB 140515A: Swift detection of a burst
  76. GRB 140508A: VLA detection
  77. Konus-Wind observation of GRB 140512A
  78. GRB 140423A: AAO optical upper limits
  79. GRB 140512A: Continued UVOT Observations
  80. GRB 140512A: Fermi GBM detection
  81. GRB 140512A: Xinglong TNT optical observation
  82. GRB 140508A: Mondy upper limit
  83. GRB 140508A: MITSuME Akeno Optical observation
  84. GRB 140512A: Swift-BAT refined analysis
  85. GRB140512A : GROND observations
  86. GRB 140512A: Swift-XRT refined Analysis
  87. GRB 140512A: Enhanced Swift-XRT position
  88. Swift Observations of GRB 140508A
  89. GRB 140512A: Optical observations from the 2.5 m NOT
  90. GRB 140428A: GROND afterglow confirmation
  91. GRB 140512A: Mondy optical detection
  92. GRB 140512A: MASTER OT decay and early light curve
  93. GRB 140512A: Swift detection of a burst with an optical counterpart
  94. GRB 140512A: MASTER optical observations
  95. GRB 140423A: Mondy optical observations
  96. GRB 140508A: Continued RATIR Optical and NIR Observations
  97. Fermi GBM Trigger 140429551 - Detection of a burst from SGR 1806-20
  98. GRB 140508A: ​HCT spectroscopy
  99. GRB 140508A: Swift/UVOT Detection
  100. GRB 140509B: MAXI/GSC detection

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