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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 080320: Enhanced Swift-XRT position
  2. GRB 080320: optical limit from IAC80
  3. GRB 080319C: Early RAPTOR Observations
  4. GRB 080319B: second epoch imaging from Canarias (correction to GCN7469)
  5. GRB 080319C: KAIT OA observations
  6. GRB 080320 - SDSS Pre-Burst Observations
  7. GRB 080320: Swift detection of a burst
  8. GRB 080320: ROTSE-III Optical Limits
  9. GRB 080319B : Lulin observation of temporal break at 0.2 days
  10. GRB 080319B: ROTSE-III Observations of Optical Counterpart
  11. GRB 080319B: optical observations
  12. GRB 080319C - SDSS Pre-Burst Observations
  13. GRB 080319A SDSS Pre-Burst Observations
  14. Swift-BAT trigger 306829 is IGR J16479-4514
  15. GRB080319B - SDSS Pre-Burst Observations
  16. GRB 080319B: RAPTOR observations of a naked eye burst
  17. GRB 080319A: Swift-XRT Team Refined Analysis
  18. GRB 080319B, Swift-BAT refined analysis
  19. GRB080319B: Prompt PROMPT Detections
  20. GRB 080319C: Swift-XRT Team Refined Analysis
  21. GRB 080319B: Swift-XRT Team Refined Analysis
  22. GRB 080319D: Swift/UVOT Refined Analysis of the Fading Optical Afterglow Candidate
  23. GRB 080319C: AGILE-MCAL observation of the prompt emission
  24. GRB 080319B: Hobby-Eberly Telescope Spectroscopy
  25. GRB 080319D: MASTER-VWF-Kislovodsk optical observation
  26. GRB 080319C: MASTER-VWF-Kislovodsk optical observation
  27. GRB 080319D: Swift detection of a burst with a possible optical afterglow
  28. GRB 080319B: TORTORA synchronous observation
  29. VLT/UVES redshift of GRB 080319B from FeII fine-structure lines
  30. GRB 080319A/B/C: INTEGRAL SPI-ACS light curves available
  31. GRB 080319B: Enhanced Swift-XRT position
  32. GRB 080319A: Enhanced Swift-XRT position
  33. GRB 080319A, Swift-BAT refined analysis
  34. GRB 080319B: REM early data
  35. GRB 080319b light curve by Pi-of-the-Sky
  36. VLT/UVES redshift of GRB 080319B
  37. GRB 080319C: Early Super-LOTIS Observations
  38. GRB 080319C: Swift detection of a burst with an optical afterglow
  39. GRB 080319C: KAIT OA candidate
  40. GRB 080319A: REM observations
  41. GRB 080319b prompt optical observation by Pi-of-the-Sky
  42. GRB 080319B: Change in power law decay index
  43. GRB 080319B: Gemini-South Spectroscopy
  44. GRB 080319A: optical observations at the NOT
  45. GRB0 080319B : LOAO optical observation
  46. GRB 080319b: Early IR Imaging from PAIRITEL
  47. GRB080319B Liverpool Telescope optical afterglow candidate
  48. GRB 080319B: Super-LOTIS Detection of a Bright OT
  49. GRB 080319B: REM observations
  50. GRB 080319B: KAIT OA
  51. GRB080319A: P60 Optical Afterglow Observations
  52. GRB 080319B: UVOT Position
  53. GRB 080319B: Swift detection of an intense burst with a bright optical counterpart
  54. GRB 080319A: Swift detection of a burst
  55. Swift Trigger 306745 is not a GRB
  56. Swift Trigger 306616 is not a GRB
  57. GRB080310, LBT and MDM photometry
  58. GRB080315: Bok Optical Observations
  59. Swift/UVOT observations of GRB 080315
  60. Swift trigger 306323: Swift-BAT/XRT refined analysis
  61. SAX J1818.6-1703: Swift detection (trigger 306379)
  62. GRB 080315: Optical observations
  63. GRB 080315: TAROT Calern observatory optical observations
  64. GRB 080315: Swift detection of a possible burst
  65. GRB080310 : Lulin Optical observations
  66. GRB080310, unusual slow decay in the optical
  67. GRB 080310: GAO 150cm telescope Optical Observation
  68. GRB080310 : Optical observations by LOAO and Lulin
  69. GRB 080310: ROTSE-III Observations of Optical Counterpart
  70. GRB080310: Optical observation by MITSuME telescope
  71. GRB080310, optical observations with the LBT
  72. GRB 080307: GAO 150cm telescope Optical Observation
  73. GRB 080229A: GAO 150cm telescope Optical Observation
  74. GRB 080310: PAIRITEL detection and PAIRITEL+KAIT+UVOT SED
  75. GRB 080307: NIR upper limit
  76. GRB 080229: NIR upper limit
  77. GRB 080310: early RAPTOR multicolor observations
  78. GRB 080310, Swift-BAT refined analysis
  79. GRB080210: optical observations
  80. GRB080307: optical upper limit
  81. GRB 080310: Swift-XRT refined analysis
  82. GRB 080310: Swift/UVOT Refined Analysis
  83. GRB 080310: Redshift from Keck/DEIMOS Spectra
  84. GRB 080310 - SDSS Pre-Burst Observations
  85. GRB080310 : Lulin optical observation
  86. GRB 080310: Enhanced Swift-XRT position
  87. GRB 080310: RRM optical photometry with the VLT
  88. GRB080310, detection of break in optical
  89. GRB 080310: VLT/UVES spectroscopy
  90. GRB080310, optical observations with LBT
  91. GRB 080310: Magellan redshift revision
  92. GRB 080310: Lick/Kast Spectroscopy
  93. GRB080310: Super-LOTIS suggestion of brightening
  94. GRB 080310, SMARTS optical/IR afterglow observations
  95. GRB 080310: REM observations
  96. GRB 080310: Magellan redshift
  97. GRB 080310 afterglow candidate (correction to UT time)
  98. GRB 080310: Swift detection of a burst with optical afterglow
  99. GRB 080310 afterglow candidate
  100. GRB080229, optical upper limit (Correction)

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