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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"

28055 results found.

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

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