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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"

32746 results found.

  1. GRB 020625: Optical observations
  2. GRB 020531: optical photometry of Chandra sources
  3. GRB020625 (=H2081): A Long Burst Localized by HETE
  4. The Probable Host Galaxy of GRB/XRF 020427
  5. GRB/XRF 020427, detection of an underlying system with the VLT
  6. GRB 020531, INT+WFC deep optical upper limits
  7. GRB020405: polarimetric observations
  8. GRB 020531, simultaneous optical observations
  9. GRB 020604, optical observations
  10. GRB 020531/Candidate Redshift
  11. GRB020531: Second epoch Chandra observations
  12. GRB020604, optical observations
  13. GRB020604, BVRcIc field photometry
  14. GRB020603, BVRcIc field observations
  15. GRB020531, BVRcIc field photometry
  16. GRB020531 Optical observations with TAROT
  17. GRB020531 Optical observations with TAROT
  18. GRB 020418, optical/near-IR observations
  19. GRB 020531, Radio Observations
  20. IPN triangulation of GRB020604
  21. GRB020531: Observations with the Chandra X-ray Observatory
  22. GRB 020603: Optical Observations
  23. GRB 020603, R-band observation
  24. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  25. GRB 020603: Optical observations
  26. IPN triangulation of GRB020603 (possible short/hard GRB)
  27. GRB 020531 optical observations with TAROT
  28. Refined IPN error box for GRB020531
  29. GRB020531, optical observations
  30. GRB020531(=H2042): Optical Observations
  31. IPN triangulation of the short, hard GRB020531 (=H2042)
  32. GRB020531(=H2042): Optical Observations
  33. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  34. GRB 020525: Optical Observations
  35. GRB020525, optical observations
  36. IPN detection of possible bursts from SGR1806-20
  37. IPN triangulation of GRB020525
  38. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  39. IPN triangulation of a burst from SGR1806-20
  40. GRB/XRF 020427, Radio Observations
  41. HST detection of the likely host galaxy of GRB 020124
  42. XRF020427: Chandra Observations and Candidate X-ray Counterparts
  43. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  44. GRB020321 : Optical observations.
  45. GRB020427 BeppoSAX NFI Observation
  46. XRF 020427
  47. GRB020331: Third Epoch and Revised Second Epoch Optical
  48. The end of BSAX GRB activities
  49. GRB 020410, Radio Observations
  50. GRB 020418: Optical observations
  51. GRB 020124: Optical observations
  52. GRB 020418: Optical observations
  53. IPN triangulation of GRB020418
  54. GRB020405: VLT observations of the OT environment
  55. GRB020410: BeppoSAX NFI observations refined analysis
  56. GRB 020409: Optical Observations
  57. Mars Odyssey joins the IPN
  58. IPN triangulation of GRB020413
  59. GRB 020409, 2-nd epoch optical observations at Terskol.
  60. GRB 020409: Optical observations
  61. GRB 020409, No Optical Detection to R = 22
  62. GRB 020409: No Evidence for an Optical Afterglow
  63. GRB 020409, 2nd epoch optical observations
  64. GRB 020331 Kyoto observation on March 31
  65. GRB 020409
  66. GRB 020409 SARA Observations
  67. GRB "020411"
  68. GRB 020409, No Optical Detection to R = 20
  69. GRB020410: BeppoSAX NFI observation
  70. GRB 020409: Optical observations
  71. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  72. GRB 020410, optical observations
  73. BeppoSAX ALERT: possible GRB020411
  74. GRB 020409, optical observations
  75. GRB 020409: Optical Observations
  76. GRB020406(?), optical observations
  77. GRB020410, optical observations
  78. BeppoSAX ALERT: possible GRB020410
  79. X-ray afterglow of GRB020321
  80. BeppoSAX GRB : GRB020409
  81. GRB020405: VLT optical observations and V band decay slope
  82. GRB020331 optical observations with RIMOTS
  83. GRB020124 optical observations with RIBOTS/RIMOTS
  84. GRB 020321: Candidate X-ray Counterparts
  85. ASM GRB candidate 020406 refined error box
  86. GRB 020405: Moderate-resolution spectroscopy
  87. GRB020406(?), optical observations
  88. GRB020405: VLT optical observations
  89. Revised Photometry of the Optical Afterglow of GRB 020405
  90. GRB020405: OT observations
  91. GRB 020331: Candidate Optical Afterglow
  92. GRB 020405: Decay index
  93. Short RXTE/ASM transient 020406; may be a GRB
  94. GRB020405, Radio Observations
  95. GRB020405: VLT spectroscopy
  96. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405
  97. GRB 020405, U-band observations
  98. GRB 020405: Optical afterglow candidate
  99. IPN localization of GRB020405
  100. GRB011212: Optical Observations

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