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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"

18104 results found.

  1. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time
  2. GRB 020812 optical observation
  3. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  4. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  5. HST Imaging of the Host of GRB 011121
  6. GRB020801, optical afterglow candidate
  7. GRB020331: Late-time Optical Light Curve (re-submission)
  8. GRB020331: Late-time Optical Light Curve
  9. IPN triangulation of GRB020714
  10. IPN triangulation of GRB150702
  11. GRB 020410: Discovery of Probable OT by HST
  12. IPN triangulation of GRB020708
  13. GRB 020705: Optical observations
  14. GRB 020625, optical observations
  15. GRB 020625: Optical observations
  16. GRB 020531: optical photometry of Chandra sources
  17. GRB020625 (=H2081): A Long Burst Localized by HETE
  18. The Probable Host Galaxy of GRB/XRF 020427
  19. GRB/XRF 020427, detection of an underlying system with the VLT
  20. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  21. AXP 1E2259+586 optical observations
  22. Fading Optical Source in the Field of GRB020531
  23. GRB 020531, INT+WFC deep optical upper limits
  24. SGR-like Bursts from the AXP 1E 2259+586
  25. GRB020405: polarimetric observations
  26. GRB 020531, simultaneous optical observations
  27. GRB 020604, optical observations
  28. GRB020531: Second epoch Chandra observations
  29. GRB020604, optical observations
  30. GRB020604, BVRcIc field photometry
  31. GRB020603, BVRcIc field observations
  32. GRB020531, BVRcIc field photometry
  33. IPN triangulation of GRB020604
  34. GRB020531 Optical Observations
  35. GRB020531: Observations with the Chandra X-ray Observatory
  36. GRB020531, optical observations
  37. GRB020531: optical observations
  38. GRB020531(=H2042): Optical Observations
  39. GRB020531(=H2042): Optical Observations
  40. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  41. GRB020525, optical observations
  42. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  43. GRB020405 field photometry at ESO
  44. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  45. XRF 020427
  46. GRB 020410, Radio Observations
  47. GRB 020124: Optical observations
  48. GRB020405: VLT observations of the OT environment
  49. IPN triangulation of GRB020413
  50. GRB020405: predicted break
  51. GRB 020409: No Evidence for an Optical Afterglow
  52. GRB 020331 Kyoto observation on March 31
  53. X-ray afterglow of GRB020321
  54. GRB020331 optical observations with RIMOTS
  55. GRB020124 optical observations with RIBOTS/RIMOTS
  56. GRB020406(?), optical observations
  57. GRB020405, Radio Observations
  58. GRB 020405, U-band observations
  59. GRB020331 NIR observation at KPNO (re-submission)
  60. GRB02033 NIR observation at KPNO
  61. GRB020331 field photometry
  62. GRB 020331, NIR observations
  63. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  64. GRB 020322: BeppoSAX observations of the X-ray afterglow
  65. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  66. Near-Infrared Observations of GRB020322 at TIRGO
  67. GRB 020322: Optical Observations
  68. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  69. GRB 020321: Optical observations
  70. GRB020317 BVRI field photometry
  71. GRB011211 revised BVRI field photometry
  72. GRB020305 BVRI field photometry
  73. GRB020322 BVRI field photometry
  74. GRB 020322: Optical Sources and Improved Astrometry
  75. GRB020317: optical observations
  76. GRB020321 optical observations
  77. GRB020321: a faint BeppoSAX detection
  78. GRB 020317 : KISO Optical Observations
  79. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  80. GRB 020305: Optical Observations
  81. GRB020317, optical observations
  82. GRB 020317: Optical observations
  83. GRB 011121: Third HST Epoch
  84. GRB020305: Properties of the Candidate Optical Afterglow
  85. GRB011130 (XRF011130) Second Epoch Chandra Observations
  86. XRF/GRB 011030: Detection of the Probable Host Galaxy
  87. GRB020305, optical observations
  88. GRB020305 (=H1939): Localization of a GRB by HETE
  89. HST Imaging of the afterglow and host of GRB 011121
  90. IPN detection and localization of Cygnus X-1 flares
  91. SGR1900+14 activity
  92. GRB020124 BVRI field photometry
  93. SN2002ap (SN/GRB?) optical spectrographic observations
  94. GRB020127 Optical Observations
  95. SN2002ap (SN/GRB?) UBVRI Field Photometry
  96. GRB020127: Chandra Observations and Prospective Counterparts
  97. pre-SN2002ap (SN/GRB?) imaging of M74
  98. GRB020124, optical observations
  99. GRB020127: Optical observations
  100. GRB 020127, I-band observations starting 3.14-hr after the event

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