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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"

17214 results found.

  1. GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC
  2. GRB020813: optical and NIR observations
  3. GRB020813: Fading X-ray Afterglow Observed with Chandra
  4. GRB020813, UBVRI field calibration
  5. Polarimetry of GRB020813: evidence for variability
  6. GRB020812: optical observations
  7. GRB020813: High-Resolution Optical Observations
  8. GRB020812: optical observations
  9. GRB020813, optical observations
  10. GRB020813, astrometric position
  11. GRB020813(=H2262): A Long, Bright Burst Localized by HETE in Near-Real Time
  12. GRB 020812 optical observation
  13. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  14. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  15. HST Imaging of the Host of GRB 011121
  16. GRB020801, optical afterglow candidate
  17. GRB020331: Late-time Optical Light Curve (re-submission)
  18. GRB020331: Late-time Optical Light Curve
  19. IPN triangulation of GRB020714
  20. IPN triangulation of GRB150702
  21. GRB 020410: Discovery of Probable OT by HST
  22. IPN triangulation of GRB020708
  23. GRB 020705: Optical observations
  24. GRB 020625, optical observations
  25. GRB 020625: Optical observations
  26. GRB 020531: optical photometry of Chandra sources
  27. GRB020625 (=H2081): A Long Burst Localized by HETE
  28. The Probable Host Galaxy of GRB/XRF 020427
  29. GRB/XRF 020427, detection of an underlying system with the VLT
  30. Gemini IR Detection of AXP 1E 2259+586 Post-Burst
  31. AXP 1E2259+586 optical observations
  32. Fading Optical Source in the Field of GRB020531
  33. GRB 020531, INT+WFC deep optical upper limits
  34. SGR-like Bursts from the AXP 1E 2259+586
  35. GRB020405: polarimetric observations
  36. GRB 020531, simultaneous optical observations
  37. GRB 020604, optical observations
  38. GRB020531: Second epoch Chandra observations
  39. GRB020604, optical observations
  40. GRB020604, BVRcIc field photometry
  41. GRB020603, BVRcIc field observations
  42. GRB020531, BVRcIc field photometry
  43. IPN triangulation of GRB020604
  44. GRB020531 Optical Observations
  45. GRB020531: Observations with the Chandra X-ray Observatory
  46. GRB020531, optical observations
  47. GRB020531: optical observations
  48. GRB020531(=H2042): Optical Observations
  49. GRB020531(=H2042): Optical Observations
  50. GRB020531(=H2042): A Short, Hard Burst Localized by HETE
  51. GRB020525, optical observations
  52. HETE Observations of GX354-0 (= MXB1728-34, so-called "Slow
  53. GRB020405 field photometry at ESO
  54. GRB(XRF) 020427: X-ray afterglow with BeppoSAX
  55. XRF 020427
  56. GRB 020410, Radio Observations
  57. GRB 020124: Optical observations
  58. GRB020405: VLT observations of the OT environment
  59. IPN triangulation of GRB020413
  60. GRB020405: predicted break
  61. GRB 020409: No Evidence for an Optical Afterglow
  62. GRB 020331 Kyoto observation on March 31
  63. X-ray afterglow of GRB020321
  64. GRB020331 optical observations with RIMOTS
  65. GRB020124 optical observations with RIBOTS/RIMOTS
  66. GRB020406(?), optical observations
  67. GRB020405, Radio Observations
  68. GRB 020405, U-band observations
  69. GRB020331 NIR observation at KPNO (re-submission)
  70. GRB02033 NIR observation at KPNO
  71. GRB020331 field photometry
  72. GRB 020331, NIR observations
  73. GRB020331(=H1963): The "Easter" Burst Detected by HETE
  74. GRB 020322: BeppoSAX observations of the X-ray afterglow
  75. GRB011211: HST Observations of Optical Afterglow and Host Galaxy
  76. Near-Infrared Observations of GRB020322 at TIRGO
  77. GRB 020322: Optical Observations
  78. GRB020127: Proposed Host Galaxy Detection and Identification of Afterglow
  79. GRB 020321: Optical observations
  80. GRB020317 BVRI field photometry
  81. GRB011211 revised BVRI field photometry
  82. GRB020305 BVRI field photometry
  83. GRB020322 BVRI field photometry
  84. GRB 020322: Optical Sources and Improved Astrometry
  85. GRB020317: optical observations
  86. GRB020321 optical observations
  87. GRB020321: a faint BeppoSAX detection
  88. GRB 020317 : KISO Optical Observations
  89. GRB020317 (=H1959): Localization by HETE of a Low Fluence GRB
  90. GRB 020305: Optical Observations
  91. GRB020317, optical observations
  92. GRB 020317: Optical observations
  93. GRB 011121: Third HST Epoch
  94. GRB020305: Properties of the Candidate Optical Afterglow
  95. GRB011130 (XRF011130) Second Epoch Chandra Observations
  96. XRF/GRB 011030: Detection of the Probable Host Galaxy
  97. GRB020305, optical observations
  98. GRB020305 (=H1939): Localization of a GRB by HETE
  99. HST Imaging of the afterglow and host of GRB 011121
  100. IPN detection and localization of Cygnus X-1 flares

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