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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"

28056 results found.

  1. IPN triangulation of GRB021014 (large error box)
  2. IPN triangulation of GRB021013 (single error box)
  3. GRB 021004: optical spectroscopy on Oct 11
  4. IPN triangulation of GRB021013 (two small error boxes)
  5. GRB021004: High-resolution optical spectroscopy
  6. XRF 020903: flattening of the optical light curve.
  7. GRB021004, UBVRcIc field photometry update
  8. IPN triangulation of GRB021008 (single error box)
  9. GRB 021004 submm observations
  10. IPN triangulation of GRB021008 (two small error boxes)
  11. GRB021004 Chandra HETG Observations
  12. GRB 021004: Optical/NIR Observations
  13. GRB 021004: Additional V-band Polarimetric Observations
  14. GRB021004: optical observation
  15. GRB 021004: Host Galaxy Star Formation Rate
  16. GRB 021004 submm observations
  17. GRB 021004: WC wind?
  18. GRB021004: NIR and Optical observations
  19. GRB 021004: Optical observations, AUDE network
  20. GRB 021004 - VLA Radio Observations
  21. GRB 021004 - Unusual Radio-to-Submm Spectrum
  22. GRB 021004: optical spectroscopy
  23. IPN triangulation of GRB021007 (annulus)
  24. GRB021004: optical observations and predicted break time
  25. GRB021004: BVRc photometry
  26. GRB021004 radio observation
  27. HETE fluences for GRB021004
  28. GRB 021004: Optical Photometry at 2.5 Days
  29. GRB 021004: polarimetric observations
  30. GRB 021004: V-band Polarimetric Observations
  31. GRB021004: Update Bisei photometric data
  32. IRAM Millimeter detection of GRB 021004
  33. GRB 021004 radio observation
  34. GRB 021004: Optical Photometry at 1.5 Days
  35. GRB021004, BVRcIc field photometry
  36. GRB021004: Optical Spectroscopy
  37. GRB 021004 radio search
  38. XRF020903, BVRI field photometry
  39. XRF020903: TNG and Asiago photometry
  40. GRB 020903: Optical observations at RIKEN
  41. XRF 020903: Correction to GCN 1560
  42. XRF 020903: VRI observations
  43. XRF 020903: R band observations
  44. XRF 020903: Archival Optical Images
  45. Radio Observations of XRF 020903: The Missing Link
  46. XRF 020903: Supernova
  47. IPN triangulation of GRB020923 (two error boxes)
  48. IPN triangulation of GRB020914B
  49. IPN triangulation of GRB020911 (2 large error boxes)
  50. GRB 020305: HST/STIS observations
  51. Confirmation of IPN error box for GRB020910
  52. IPN triangulation of GRB020910
  53. IPN GCN Circulars now to be issued without restriction
  54. Single IPN error box for GRB020904
  55. XRF 020903: optical observation at Kyoto
  56. GRB020322 : HST/STIS observations
  57. XRF 020903: Optical observations
  58. IPN triangulation of GRB020904
  59. INTEGRAL GRBs added to GCN
  60. SGR1900+14 burst localized by HETE
  61. GRB020813: High-resolution optical spectroscopy
  62. GRB020812: negative optical observations
  63. GRB 020812: optical observation at Kyoto University
  64. Second epoch K band imaging of GRB 020819
  65. GRB 020813 : HST observations
  66. GRB 020812: early time optical observation at Ouda Station
  67. GRB020813: Magellan BVRI Photometry
  68. GRB 020819: Optical observations
  69. K band observation of GRB 020819
  70. GRB020813: optical and NIR observations
  71. GRB020813: Fading X-ray Afterglow Observed with Chandra
  72. GRB020813, UBVRI field calibration
  73. GRB020812: NIR observations
  74. Polarimetry of GRB020813: evidence for variability
  75. GRB020813 IRAM millimeter observations
  76. GRB020812: optical observations
  77. GRB020813: High-Resolution Optical Observations
  78. GRB 020812: optical observation at Bisei
  79. GRB020813: Early Time Magnitude
  80. Millimeter observation of GRB 020813
  81. GRB020812: optical observations
  82. GRB 020813 : KISO multiband optical observations
  83. GRB020813, optical observations
  84. IPN error box for GRB020813
  85. GRB020813, astrometric position
  86. Spectropolarimetry of GRB 020813
  87. GRB 020812 optical observation
  88. GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time
  89. GRB020801: Imaging of Suggested OT Counterpart at the Magellan
  90. HST Imaging of the Host of GRB 011121
  91. GRB020801, optical afterglow candidate
  92. GRB020331: Late-time Optical Light Curve (re-submission)
  93. GRB020331: Late-time Optical Light Curve
  94. IPN triangulation of GRB020714
  95. IPN triangulation of GRB020715 (=GRB150702)
  96. IPN triangulation of GRB020714
  97. IPN triangulation of GRB150702
  98. GRB 020410: Discovery of Probable OT by HST
  99. GRB 020124, HST observations of the fading afterglow
  100. IPN triangulation of GRB020708

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