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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. HST detection of the likely host galaxy of GRB 020124
  2. GRB020405 field photometry at ESO
  3. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  4. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  5. GRB020321 : Optical observations.
  6. GRB020427 BeppoSAX NFI Observation
  7. XRF 020427
  8. GRB020331: Third Epoch and Revised Second Epoch Optical
  9. The end of BSAX GRB activities
  10. GRB 020410, Radio Observations
  11. GRB 020418: Optical observations
  12. GRB 020124: Optical observations
  13. GRB 020418: Optical observations
  14. IPN triangulation of GRB020418
  15. GRB020405: VLT observations of the OT environment
  16. GRB020410: BeppoSAX NFI observations refined analysis
  17. GRB 020409: Optical Observations
  18. Mars Odyssey joins the IPN
  19. IPN triangulation of GRB020413
  20. GRB 020409, 2-nd epoch optical observations at Terskol.
  21. GRB020405: predicted break
  22. GRB 020409: Optical observations
  23. GRB 020409, No Optical Detection to R = 22
  24. GRB020410: second BeppoSAX NFI observation
  25. GRB 020409: No Evidence for an Optical Afterglow
  26. GRB 020409, 2nd epoch optical observations
  27. GRB 020331 Kyoto observation on March 31
  28. GRB 020409
  29. GRB 020409 SARA Observations
  30. GRB "020411"
  31. GRB 020409, No Optical Detection to R = 20
  32. GRB020410: BeppoSAX NFI observation
  33. GRB 020409: Optical observations
  34. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  35. GRB 020410, optical observations
  36. BeppoSAX ALERT: possible GRB020411
  37. GRB 020409, optical observations
  38. GRB 020409: Optical Observations
  39. GRB020406(?), optical observations
  40. GRB020410, optical observations
  41. BeppoSAX ALERT: possible GRB020410
  42. X-ray afterglow of GRB020321
  43. BeppoSAX GRB : GRB020409
  44. GRB020331: Confirmation of Afterglow Candidate with Magellan
  45. GRB020405: VLT optical observations and V band decay slope
  46. GRB020331 optical observations with RIMOTS
  47. GRB020124 optical observations with RIBOTS/RIMOTS
  48. GRB 020321: Candidate X-ray Counterparts
  49. ASM GRB candidate 020406 refined error box
  50. GRB 020405: Moderate-resolution spectroscopy
  51. GRB020331: Optical Observations of Afterglow Candidate
  52. GRB020406(?), optical observations
  53. GRB020405: VLT optical observations
  54. Revised Photometry of the Optical Afterglow of GRB 020405
  55. GRB020405: OT observations
  56. GRB 020331: Candidate Optical Afterglow
  57. GRB 020405: Decay index
  58. Short RXTE/ASM transient 020406; may be a GRB
  59. GRB020405, Radio Observations
  60. GRB020405: VLT spectroscopy
  61. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  62. V band observations of GRB020405
  63. GRB 020405, U-band observations
  64. GRB 020405: Optical afterglow candidate
  65. IPN localization of GRB020405
  66. GRB011212: Optical Observations
  67. GRB 020331: NIR Observations
  68. GRB 020331: NIR Observations
  69. GRB020331 NIR observation at KPNO (re-submission)
  70. GRB02033 NIR observation at KPNO
  71. GRB020331 field photometry
  72. GRB 020331 Optical Observations
  73. GRB 020331, NIR observations
  74. GRB 020331: Optical observations
  75. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  76. GRB 020321: Infrared observations
  77. GRB 020322: BeppoSAX observations of the X-ray afterglow
  78. SN 2002ap - peak brightness date (SN/GRB?)
  79. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  80. GRB 020322, Radio observations
  81. Near-Infrared Observations of GRB020322 at TIRGO
  82. GRB 020321, Radio Observations
  83. GRB 020322: Optical Observations
  84. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  85. GRB 020321: Optical observations
  86. GRB020317 BVRI field photometry
  87. GRB011211 revised BVRI field photometry
  88. GRB020305 BVRI field photometry
  89. GRB020322 BVRI field photometry
  90. GRB 020322 optical observations
  91. GRB020322: Candidate Optical Afterglow
  92. GRB 020322 optical observation
  93. GRB020317 : Near IR Observations from Mt Abu Observatory
  94. GRB 020322: Optical Sources and Improved Astrometry
  95. GRB020322, optical observations
  96. GRB 020322: Optical candidate
  97. XMM-Newton observation of GRB020322
  98. GRB020322: Optical Observations
  99. GRB020322: BeppoSAX/NFI Observations
  100. Bepposax GRB020322 The second springtime BSAX GRB

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