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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').
  1. GRB 020531/Candidate Redshift
  2. GRB020531: Detection of Candidate Host Galaxy
  3. GRB020531: Second epoch Chandra observations
  4. GRB020604, optical observations
  5. GRB020604, BVRcIc field photometry
  6. GRB020603, BVRcIc field observations
  7. GRB020531, BVRcIc field photometry
  8. GRB020531 Optical observations with TAROT
  9. GRB020531 Optical observations with TAROT
  10. GRB 020418, optical/near-IR observations
  11. GRB 020531, Radio Observations
  12. IPN triangulation of GRB020604
  13. GRB020531 Optical Observations
  14. GRB020531: Observations with the Chandra X-ray Observatory
  15. GRB 020603: Optical Observations
  16. GRB 020603, R-band observation
  17. Correction to IPN triangulation of GRB020603 (possible short/hard burst)
  18. GRB020531: Upper Limit for Detection of Two TAROT Sources
  19. GRB 020603: Optical observations
  20. IPN triangulation of GRB020603 (possible short/hard GRB)
  21. GRB 020531 optical observations with TAROT
  22. Refined IPN error box for GRB020531
  23. GRB020531, optical observations
  24. GRB020531: optical observations
  25. GRB020531, optical observation
  26. GRB020531(=H2042): Optical Observations
  27. IPN triangulation of the short, hard GRB020531 (=H2042)
  28. GRB020531(=H2042): Optical Observations
  29. GRB020531: Optical observations
  30. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  31. GRB 020525: Optical Observations
  32. GRB020525, optical observations
  33. IPN detection of possible bursts from SGR1806-20
  34. IPN triangulation of GRB020525
  35. XRF 020427: Sudden Ionospheric Disturbance (SID)
  36. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  37. XRF020427: Chandra Identification of a Likely X-ray Counterpart
  38. IPN triangulation of a burst from SGR1806-20
  39. GRB/XRF 020427, Radio Observations
  40. HST detection of the likely host galaxy of GRB 020124
  41. GRB020405 field photometry at ESO
  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. GRB020405: predicted break
  61. GRB 020409: Optical observations
  62. GRB 020409, No Optical Detection to R = 22
  63. GRB020410: second BeppoSAX NFI observation
  64. GRB 020409: No Evidence for an Optical Afterglow
  65. GRB 020409, 2nd epoch optical observations
  66. GRB 020331 Kyoto observation on March 31
  67. GRB 020409
  68. GRB 020409 SARA Observations
  69. GRB "020411"
  70. GRB 020409, No Optical Detection to R = 20
  71. GRB020410: BeppoSAX NFI observation
  72. GRB 020409: Optical observations
  73. April 11 BeppoSAX event (GRB020411) is likely not a GRB
  74. GRB 020410, optical observations
  75. BeppoSAX ALERT: possible GRB020411
  76. GRB 020409, optical observations
  77. GRB 020409: Optical Observations
  78. GRB020406(?), optical observations
  79. GRB020410, optical observations
  80. BeppoSAX ALERT: possible GRB020410
  81. X-ray afterglow of GRB020321
  82. BeppoSAX GRB : GRB020409
  83. GRB020331: Confirmation of Afterglow Candidate with Magellan
  84. GRB020405: VLT optical observations and V band decay slope
  85. GRB020331 optical observations with RIMOTS
  86. GRB020124 optical observations with RIBOTS/RIMOTS
  87. GRB 020321: Candidate X-ray Counterparts
  88. ASM GRB candidate 020406 refined error box
  89. GRB 020405: Moderate-resolution spectroscopy
  90. GRB020331: Optical Observations of Afterglow Candidate
  91. GRB020406(?), optical observations
  92. GRB020405: VLT optical observations
  93. Revised Photometry of the Optical Afterglow of GRB 020405
  94. GRB020405: OT observations
  95. GRB 020331: Candidate Optical Afterglow
  96. GRB 020405: Decay index
  97. Short RXTE/ASM transient 020406; may be a GRB
  98. GRB020405, Radio Observations
  99. GRB020405: VLT spectroscopy
  100. Fading Optical Afterglow and Possible Host Galaxy of GRB 020405

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