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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').

10043 results found.

  1. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  2. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  3. GRB020801: Candidate OT present in DSS
  4. HST Imaging of the Host of GRB 011121
  5. Further refinement to IPN error box for GRB020531
  6. GRB020625 (=H2081): A Long Burst Localized by HETE
  7. GRB/XRF 020427, detection of an underlying system with the VLT
  8. AXP 1E2259+586 optical observations
  9. Fading Optical Source in the Field of GRB020531
  10. GRB020405: polarimetric observations
  11. GRB 020531/Candidate Redshift
  12. GRB020531: Second epoch Chandra observations
  13. GRB020531 Optical Observations
  14. GRB020531: Observations with the Chandra X-ray Observatory
  15. GRB020531: Upper Limit for Detection of Two TAROT Sources
  16. Refined IPN error box for GRB020531
  17. GRB020531(=H2042): Optical Observations
  18. IPN triangulation of the short, hard GRB020531 (=H2042)
  19. GRB020531(=H2042): Optical Observations
  20. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  21. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  22. GRB020405 field photometry at ESO
  23. GRB020331: Third Epoch and Revised Second Epoch Optical
  24. GRB020405: VLT observations of the OT environment
  25. GRB 020409: Optical Observations
  26. X-ray afterglow of GRB020321
  27. GRB020331: Confirmation of Afterglow Candidate with Magellan
  28. GRB020405: VLT optical observations and V band decay slope
  29. GRB020331 optical observations with RIMOTS
  30. GRB020124 optical observations with RIBOTS/RIMOTS
  31. GRB 020405: Moderate-resolution spectroscopy
  32. GRB020331: Optical Observations of Afterglow Candidate
  33. GRB020405: VLT optical observations
  34. GRB020405: VLT spectroscopy
  35. V band observations of GRB020405
  36. GRB011212: Optical Observations
  37. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  38. Near-Infrared Observations of GRB020322 at TIRGO
  39. GRB 020322: Optical Sources and Improved Astrometry
  40. GRB 020322: Optical candidate
  41. XMM-Newton observation of GRB020322
  42. GRB 020317 : KISO Optical Observations
  43. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  44. GRB011130 (XRF011130) Second Epoch Chandra Observations
  45. GRB020305: Subaru Optical Observations
  46. IPN triangulation of GRB020305 (HETE 1939)
  47. GRB020305 (=H1939): Localization of a GRB by HETE
  48. IPN/HETE Detection of Bursts from SGR1900+14
  49. IPN Upper Limits to a GRB Associated With SN2002ap
  50. IPN triangulation of GRB020127 (=H1902)
  51. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  52. IPN triangulation of GRB020124 (HETE 1896)
  53. GRB020124(=H1896): Localization of a Long GRB by HETE
  54. GRB011212, Optical Observations
  55. Optical polarization observations for GRB011211
  56. Color indices of the afterglow of GRB011211
  57. GRB011212: Optical observations at Gunma
  58. GRB 011130: Optical Observations of X-ray and Radio Sources
  59. GRB 011211: TNG Spectroscopic Observations
  60. GRB011212 (=H10001): An X-Ray Rich GRB Detected by HETE
  61. XMM-Newton observation of GRB011211
  62. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  63. GRB 011130: Optical Observations of Chandra Sources
  64. GRB 011130: Optical Observations of Chandra sources
  65. GRB011130 (XRF011130) Chandra Observations
  66. GRB011130 (=XRF011130): Scheduled Target of Opportunity
  67. GRB011130 (=XRF011130): Second Revised Localization by HETE
  68. GRB 011130 I-band Observation
  69. GRB011130 (=XRF011130): Revised Localization of an X-ray
  70. GRB 011121
  71. GRB011130 (=H1864): An X-Ray Rich GRB Detected by HETE
  72. GRB 011121: NIR observations, host galaxy?
  73. GRB 011030: TNG K-band observation
  74. XRF011030: J and K band observations
  75. GRB 011030: K-band observations
  76. GRB 011030 I-band Observation
  77. GRB011019: Subaru Optical Observations
  78. GRB 011030 I-band Observations
  79. GRB 011030 K-band Observations
  80. GRB010921, optical observations
  81. GRB011019: A Faint, X-ray Rich GRB localized by HETE
  82. GRB010928(=H1770): Localization of a Long GRB by HETE
  83. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  84. GRB 010921 DPOSS Images Available
  85. IPN triangulation of GRB010921 (=H1761)
  86. H1761: A Bright GRB Detected by HETE
  87. Probable SGR or Short Duration GRB Detected by HETE
  88. BeppoSAX/GRBM detection of GRB010728
  89. GRB 010222 - WHT BVRI images
  90. GRB010629: Optical Observations
  91. SGR1900+14: High Fluence Burst Localized by HETE
  92. GRB010629: A Burst Localized by HETE
  93. SGR1900+14: Second Burst Localized by HETE
  94. SGR1900+14: A Burst Localized by HETE
  95. SGR1806-20: A Second, Intense Burst Localized by HETE
  96. SGR1806-20: Localization by HETE
  97. GRB010214, optical observations
  98. GRB Observation Report
  99. REVISED LOCATION OF GRB010326A
  100. GRB010326B: Localization by HETE (2nd GRB for this date)

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